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Thermal and cardiorespiratory responses of horses to submaximal exercise under hot and humid conditions.
The objective of this study is to determine the effects of heat, and heat and high relative humidity (RH) on the thermal and cardiorespiratory responses to exercise and recovery. Five Thoroughbred horses (age 3 to 6) completed exercise tests under each of 3 environmental conditions: cool, dry (CD, room temperature (T) = 20 degrees C, RH = 45-55%), hot, dry (HD, T = 32-34 degrees C, RH = 45-55%) and hot, humid (HH, T = 32-34 degrees C, RH = 80-85%). Horses were exercised at a workload equal to 50% of VO2max on a treadmill set at a 10% slope until attainment of a pulmonary artery blood (PA) temperature of 41.5 degrees C followed by a 30 min walking recovery (0% slope), and a further 30 min standing recovery in the same environmental conditions. Blood (PA), rectal, skin (dorsal aspect of the thorax) and muscle (middle gluteal muscle) temperatures and heart rate were measured before, during and after exercise. Respiratory rate was measured before exercise and during the 60 min recovery period. Exercise duration for HD (mean +/- s.e. 28 +/- 2 min) and HH (16.5 +/- 1 min) was significantly (P < 0.05) decreased when compared with CD (37 +/- 2 min). The rate of increase in PA blood temperature was significantly higher in HH (0.26 +/- 0.03 degrees C/min) than in HD (0.17 +/- 0.04 degrees C/min) and CD (0.12 +/- 0.05 degrees C/min). Temperature in the middle gluteal muscle after 15 min of exercise was significantly higher in HH (41.9 +/- 0.3 degrees C) than in HD (40.7 +/- 0.25 degrees C) and CD (40.15 +/- 0.35 degrees C); whereas rectal temperature at the end of exercise was significantly lower in HH (39.1 +/- 0.3 degrees C) than in HD (40.1 +/- 0.3 degrees C) and CD (40 +/- 0.2 degrees C). The PA blood:skin temperature difference was significantly smaller in HD and HH than in CD. When compared with CD, temperatures at all sites were higher in HD and HH during the 60 min of recovery. Throughout exercise and recovery, heart rate was significantly higher in HH when compared with the other conditions. Post exercise respiratory rate was significantly higher in HD and HH than in CD throughout recovery. It was concluded that the added thermal loads of high temperature and relative humidity increased the rate of heat storage during exercise and delayed dissipation of heat during recovery. The impairment to heat dissipation was probably the result of a reduced capacity for heat transfer from the skin to the environment. |
[Effect of estrogen or progesterone combined with paclitaxel on human ovarian cancer cell growth and Drosha expression].
To investigate the effect of estrogen (E2), progesterone(P4), and paclitaxel (taxol) on the growth of primary human ovarian cancer cells in vitro and the expression of Drosha. Human ovarian cancer cells were treated with estrogen, progesterone or in combination with paclitaxel in vitro. The inhibition rate of ovarian cancer cells was assessed by methyl thiazolyl tetrazolium (MTT) assay. Apoptosis rate and cell cycle were determined by FACS analysis. The relative abundence of Drosha expression was detected by real-time quantitative PCR (qRT-PCR) and Western blotting. The inhibition rate of the estrogen group, progesterone group, paclitaxel group, E2(+)Taxol group, P4(+)Taxol group was (31.53 ± 8.21)%, (25.22 ± 15.50)%, (46.71 ± 4.25)%, (69.46 ± 3.71)%, and (47.35 ± 39.02)%, respectively, significantly higher than that of the control group (0%, P<0.05 for all). Relative to the ER (-) in ovarian cancer cells,Drosha mRNA expression level of estrogen group, progesterone group, paclitaxel group, E2(+) Taxol group,and P4(+)Taxol group was 1.62 ± 0.10,1.60 ± 0.10,1.75 ± 0.16,1.95 ± 0.20, and 1.53 ± 0.06, respectively, significantly higher than that of the control group (1.00, P<0.05 for all). Relative to the ER (+)in ovarian cancer cells,the Drosha mRNA expression level of estrogen group, progesterone group, paclitaxel group, E2(+)taxol group, and P4(+)Taxol group was 1.03 ± 0.14, 1.60 ± 0.09, 1.75 ± 0.16, 1.60 ± 0.10, 1.53 ± 0.06, respectively except estrogen group, significantly higher than that of the control group (1.00, P<0.05). Relative to the ER (-) in ovarian cancer cells, the Drosha protein expression levels of the control group, estrogen group, progesterone group, paclitaxel group, E2(+) taxol group, and P4(+) Taxol group were 0.25 ± 0.05, 0.87 ± 0.30, 0.85 ± 0.38, 1.30 ± 0.21, 1.75 ± 0.83, 1.62 ± 0.82, respectively, with a significant difference between the experimental groups and the control group (P<0.05). Relative to the ER(+)ovarian cancer cells, the Drosha protein expression levels in the estrogen group, progesterone group, paclitaxel group, E2(+) taxol group, and P4(+) taxol group, were 0.28 ± 0.16, 0.85 ± 0.38, 1.30 ± 0.21, 0.94 ± 0.18, and 1.62 ± 0.82, respectively except estrogen group, significantly higher than that of the control group (0.25 ± 0.05, P<0.05 for all). Estrogen and progesterone in combination with paclitaxel can inhibit the growth of human ovarian cancer cells in vitro, and affect the cell apoptosis rate. Estrogen and taxol can alter the cell cycle. Estrogen and progesterone combined with paclitaxel show tumor suppressing or sensitizing effect through upregulated Drosha expression, and are associated with the estrogen receptor expression. |
Quantifying the Self-Assembly Behavior of Anisotropic Nanoparticles Using Liquid-Phase Transmission Electron Microscopy.
For decades, one of the overarching objectives of self-assembly science has been to define the rules necessary to build functional, artificial materials with rich and adaptive phase behavior from the bottom-up. To this end, the computational and experimental efforts of chemists, physicists, materials scientists, and biologists alike have built a body of knowledge that spans both disciplines and length scales. Indeed, today control of self-assembly is extending even to supramolecular and molecular levels, where crystal engineering and design of porous materials are becoming exciting areas of exploration. Nevertheless, at least at the nanoscale, there are many stones yet to be turned. While recent breakthroughs in nanoparticle (NP) synthesis have amassed a vast library of nanoscale building blocks, NP-NP interactions in situ remain poorly quantified, in large part due to technical and theoretical impediments. While increasingly many applications for self-assembled architectures are being demonstrated, it remains difficult to predict-and therefore engineer-the pathways by which these structures form. Here, we describe how investigations using liquid-phase transmission electron microscopy (TEM) have begun to play a role in pursuing some of these long-standing questions of fundamental and far-reaching interest. Liquid-phase TEM is unique in its ability to resolve the motions and trajectories of single NPs in solution, making it a powerful tool for studying the dynamics of NP self-assembly. Since 2012, liquid-phase TEM has been used to investigate the self-assembly behavior of a variety of simple, metallic NPs. In this Account, however, we focus on our work with anisotropic NPs, which we show to have very different self-assembly behavior, and especially on how analysis methods we and others in the field are developing can be used to convert their motions and trajectories revealed by liquid-phase TEM into quantitative understanding of underlying interactions and dynamics. In general, liquid-phase TEM studies may help bridge enduring gaps in the understanding and control of self-assembly at the nanoscale. For one, quantification of NP-NP interactions and self-assembly dynamics will inform both computational and statistical mechanical models used to describe nanoscale phenomena. Such understanding will also lay the groundwork for establishing new and generalizable thermodynamic and kinetic design rules for NP self-assembly. Synergies with NP synthesis will enable investigations of building blocks with novel, perhaps even evolving or active behavior. Moreover, in the long run, we foresee the possibility of applying the guidelines and models of fundamental nanoscale interactions which are uncovered under liquid-phase TEM to biological and biomimetic systems at similar dimensions. |
Experimental study on the effect of cyclosporine A drug delivery system implanted in anterior chamber on high-risk corneal graft rejection.
To evaluate the efficacy and feasibility of cyclosporine A (CsA) drug delivery system (DDS) for prevention of high-risk corneal graft rejection in rats. (1) Corneal vascularization was induced in 60 Wistar rats (60 eyes) by passing 8-0 silk suture in corneal stroma. (2) Wistar rats with corneal vascularization received corneal grafts from Sprague-Dawley rats to develop the high-risk keratoplasty models. (3) Forty animal models (40 eyes) were divided into 4 groups: receiving no therapy, 1% CsA eye drop, CsA DDS implanted subconjunctively, or CsA DDS implanted in anterior chamber. During the 1-month follow-up, survival times (the occurrence time of graft rejection) of these animal models were recorded, and CsA concentration in aqueous humor was regularly detected. (4) Other 8 normal Wistar rats (16 eyes) were divided into 2 groups with CsA DDS implanted subconjunctively or in anterior chamber. Histopathological examination on local ocular tissues was performed at 2 and 4 weeks after DDS implantation. Corneal vascularization was successfully induced in 51 Wistar rats (51 eyes), but failed in the other 9 rats because of complications in or after operation. 40 high-risk keratoplasty animal models (40 eyes) were all successful which exhibited typical rejection processes. The mean survival time of 4 trial groups was (8.20 +/- 1.48) days, (10.60 +/- 1.90) days, (11.40 +/- 2.50) days and (17.00 +/- 6.05) days respectively. The mean CsA concentration in aqueous humor of 4 trial groups was 0 micro g/L, (47.90 +/- 3.48) micro g/L, (56.50 +/- 6.24) micro g/L, (121.70 +/- 16.79) micro g/L respectively. The mean CsA concentration in aqueous humor of CsA DDS subconjunctively implanted group was (58.96 +/- 3.66) micro g/L, (59.74 +/- 6.50) micro g/L, (50.66 +/- 4.13) micro g/L at 1, 2 and 4 weeks postoperatively, and the mean CsA concentration of CsA DDS intrachamberly implanted group was (133.10 +/- 18.30) micro g/L, (124.56 +/- 9.65) micro g/L, (107.45 +/- 11.48) micro g/L at the corresponding time. After CsA DDS implantation, chronic inflammation occurred in local ocular tissues, and the inflammation reduced gradually. The CsA DDS, especially CsA DDS implanted in anterior chamber, can significantly improve CsA concentration in aqueous humor and maintain a high concentration for a long period of time, which has strong effects on prevention of high-risk corneal graft rejection with only little toxicity. It is a safe and effective method for CsA application. |
[AN ENTRY FOR A "DICTIONARY OF GENETICS" GENERATION AND ASPECTS OF HEREDITY FROM THE PRESOCRATICS TO GALEN: THE MAIN NOTIONS AND THE TECHNICAL TERMINOLOGY].
This article aims at dealing with the historical development and the terminology of the notion of generation in ancient Greece, taking as well into consideration several aspects of the notion of heredity, for, at present, research in this field lacks a consistent encyclopedic entry on such subjects. The Presocratic - mainly Empedoclean - notions of 'mixing' and 'separation' lurk behind the Hippocratic treatise De genitura/De natura pueri, in which the process of generation is explained through the 'mixing' mechanism of a female semen and a male one. Semen comes from each part of both parents, so it is sound from the sound parts, and unhealthy from the unhealthy parts. It is considered as the "foam of blood" (Diogenes, A 24 DK), gathering itself into a web of blood vessels that bring it to the genital organs. The mixed semen keeps on fixing itself in the womb thanks to pneuma ('breath'), until the embryo takes human shape. Generation is influenced by both the environment (Airs, Waters, Places) and dietetics (On Regimen, I). Male and female are on different levels in CH, since the former is characterized as hot and strong, and the latter is considered as cold and weak; as a consequence of this, the articulation takes longer in the case of a female embryo. On the other hand, the pangenesis and the preformism theory claim for a strong mutual relationship. Sex determination depends from the 'prevalence' of the male or female semen. The generation of twins of different sex depends from such 'prevalence', as well as from the conformation of the womb and its places (right/male, left/female). Both nature (physis) and use (nomos) have a role in the mechanism of inheritance, as the case of the Macrocephalians in Airs Waters Places shows. On the other hand, Plato's Timaeus exemplifies the theory according to which semen derives from the spinal marrow. The structures of the body - bones, flesh, nerves - aim at protecting marrow itself for the sake of maintaining the continuity of the process of generation. For Aristotle, the female provides a specific contribution to generation, that is menstrual blood, the 'material' that will be fashioned into shape by the 'principle of movement' provided in the male semen. Menstrual blood and semen share the same nature, for they are both the ultimate secretion of nutriment, that is the residue of concocted blood. Considering the female as colder that the male, Aristotle develops the concept of the female as privation in relation to the male. The notion of 'prevalence' in its turn provides explanation for similarities between parents and children. The theory of a double semen originating itself in blood comes back again in Galen's treatise On semen, which links together the Hippocratic notion of a bi-sexual semen and the Aristotelian one of a specific female contribution, the menstrual blood, that provides nutrition for the embryo. Furthermore, similarities between sons and mothers are considered in Definitiones medicae as the main proof of the existence of a female semen. Actually the Alexandrian physicians - Herophilus for instance - considered the female sexual organs anatomy as perfectly corresponding to the male one. As a consequence of the synthesis between the Hippocratic and the Aristotelian tradition, Galen's embryological doctrines were very long-lasting in medical thought. |
Shear stress induces ATP-independent transient nitric oxide release from vascular endothelial cells, measured directly with a porphyrinic microsensor.
Shear stress causes the vascular endothelium to release nitric oxide (NO), which is an important regulator of vascular tone. However, direct measurement of NO release after the imposition of laminar flow has not been previously accomplished because of chemical (oxidative degradation) and physical (diffusion, convection, and washout) complications. Consequently, the mechanism, time course, kinetics, and Ca2+ dependence of NO release due to shear stress remain incompletely understood. In this study, we characterized these parameters by using fura 2 fluorescence and a polymeric porphyrin/Nafion-coated carbon fiber microsensor (detection limit, 5 nmol/L; response time, 1 millisecond) to directly measure changes in [Ca2+]i and NO release due to shear stress or agonist (ATP or brominated Ca2+ ionophore [Br-A23187]) from bovine aortic endothelial cells. The cells were grown to confluence on glass coverslips, loaded with fura 2-AM, and mounted in a parallel-plate flow chamber (volume, 25 microL). The microsensor was positioned approximately 100 microns above the cells with its long axis parallel to the direction of flow. Laminar flow of perfusate was maintained from 0.04 to 1.90 mL/min, which produced shear stresses of 0.2 to 10 dyne/cm2. Shear stress caused transient NO release 3 to 5 seconds after the initiation of flow and 1 to 3 seconds after the rise in [Ca2+]i, which reached a plateau after 35 to 70 seconds. Although the amount (peak rate) of NO release increased as a function of the shear stress (0.08 to 3.80 pmol/s), because of the concomitant increase in the flow rate, the peak NO concentration (133 +/- 9 nmol/L) remained constant. Maintenance of flow resulted in additional transient NO release, with peak-to-peak intervals of 15.5 +/- 2.5 minutes. During this 13- to 18-minute period, when the cells were unresponsive to shear stress, exogenous ATP (10 mumol/L) or Br-A23187 (10 mumol/L) evoked NO release. Prior incubation of the cells with exogenous NO or the removal and EGTA (100 mumol/L) chelation of extracellular Ca2+ blocked shear stress but not ATP-dependent NO release. The kinetics of shear stress-induced NO release (2.23 +/- 0.07 nmol/L per second) closely resembled the kinetics of Ca2+ flux but differed markedly from the kinetics of ATP-induced NO release (5.64 +/- 0.32 nmol/L per second). These data argue that shear stress causes a Ca(2+)-mediated ATP-independent transient release of NO, where the peak rate of release but not the peak concentration depends on the level of shear stress.(ABSTRACT TRUNCATED AT 400 WORDS) |
Induction or escalation therapy for patients with multiple sclerosis?
The concept of induction followed by a long-term maintenance treatment has attracted much attention for the treatment of multiple sclerosis over the 30 past years. It was first demonstrated by the combination of induction therapy with mitoxantrone (six-monthly courses) followed by maintenance therapy with an immunomodulatory treatment such as an interferon-β or glatiramer acetate. Long-term observational studies confirmed that this therapeutic regimen provides a rapid reduction in disease activity and sustained disease control up to at least five years in 60% of patients. A better treatment response was observed in patients with early signs of aggressive disease, as shown in randomised studies (using six-monthly 12mg/m2 of mitoxantrone intravenously at a cumulative dose of 72mg/m2, followed by an interferon-β) as well as in long-term observational studies. But the safety profile of mitoxantrone make it more particularly suitable for young patients with frequent early relapses with incomplete recovery and multiple gadolinium-enhancing T1 lesions or spinal cord lesions on magnetic resonance imaging. More recently approved, the second candidate for an induction strategy is alemtuzumab: phases II and III randomised studies showed the superiority of alemtuzumab 12mg per day given intravenously for only five days and repeated for 3 days one year later, compared with interferon-β three times a week. Like with mitoxantrone, results supported the concept of long-term benefit after a short induction rather than escalation, in a subset of patients with early very active MS, with a sustained control of the disease for up to 7 years in 60% of patients in the phase III extension studies and in a long-term observational study. On the contrary, when alemtuzumab was first studied later in the disease course, results were disappointing. However, the risk of developing manageable but potentially severe systemic autoimmune diseases within the years following the last course of alemtuzumab make it, like mitoxantrone, more suitable for patients with early aggressive MS. More recently, cladribine an oral immunosuppressant, showed interesting results in a phase III study extension suggesting its potential induction effect, since after two cycles of treatment (5 days repeated 1 month later) at one year of interval, the remained low up to 4 years of follow-up, in the absence of any new treatment. However, today other immunosuppressive drugs have proved to be strongly and rapidly efficacious in treating highly active MS patients but through a mechanism of continuous immunosuppression (i.e., natalizumab and ocrelizumab). Indeed, disease activity can reappear rapidly after stopping these drugs, sometimes associated with a rebound of the inflammatory process, which is the contrary of a mechanism of induction that is associated with a remnant effect. Taking into account advantages and disadvantages of the different DMDs, which enriched the today therapeutic arsenal for MS, we propose in this paper some algorithms summarizing our reflexion about using an escalation strategy or an induction strategy according to disease course and activity. |
A Real-World Retrospective Cohort Study of Combined Therapy with Bevacizumab and Paclitaxel in Japanese Patients with Metastatic Breast Cancer.
Combined therapy with bevacizumab and paclitaxel (BP regimen) as a first-line treatment has proven highly effective with good tolerance for patients with metastatic breast cancer (MBC). The objective of this study was to examine the efficacy and safety of the BP regimen for Japanese patients with MBC in real-world clinical settings. From June 2012 through May 2014, we recruited 94 patients at 10 medical institutions. The primary endpoint was time to treatment failure (TTF), and the secondary endpoints were overall survival (OS) and safety. Objective response was assessed according to the Response Evaluation Criteria in Solid Tumors. Adverse events (AEs) were graded according to the National Cancer Institute Common Terminology Criteria for Adverse Events version 4.0-Japan Clinical Oncology Group. Nighty patients with MBC (mean 58 years, range: 34-80 years) were enrolled, and 60 (66.6%) and 52 (57.7%) had undergone prior chemotherapy as adjuvant treatment and treatment for MBC, respectively. Median TTF was 6.2 months (95% confidence interval [CI], 4.2-8.3 months), and median OS was 15.4 months (95% CI, 12.0-18.9 months). The overall response rate was 67.8% (95% CI: 57.1-77.2%). A total of 28 patients (31.1%) required a dose reduction of paclitaxel. Forty-five, 42, and 3 patients received the initial doses of 90, 80, and 60 mg/m2, respectively. Among patients who received the initial doses of 90 mg/m2, 13 patients (28.9%) unexpectedly required a dose reduction of ≥20 mg/m2. The BP regimen was discontinued for 66 (73.3%) of the 90 patients, 52 (57.7%) of whom experienced "disease progression." Grade 3/4 hematologic AEs developed in 51 patients (56.6%), with leukopenia and neutropenia in 16 patients (17.8%) and 21 patients (23.3%), respectively. Grade 3 nonhematologic AEs developed in 8 patients (8.9%), with the most common nonhematologic AE of peripheral neuropathy in 4 patients (4.4%). No Grade 4 nonhematologic AEs developed. Peripheral neuropathy [56 patients (62.2%) ], nail discoloration [53 patients (58.9%) ], and fatigue [51 patients (56.7%) ] were the most predominant AEs-the known AEs of paclitaxel. The BP regimen was active and well tolerated in the real-world clinical settings. As many as 28.9% of patients who received the initial dose of 90 mg/m2 required a dose reduction of paclitaxel by 20 mg/m2. Therefore, there is a need to find a therapeutic regimen that is less likely to result in dose reductions for patients with MBC who undergo a BP regimen using the initial paclitaxel dose of 90 mg/m2. |
Perioperative use of corticosteroid and bupivacaine combination in lumbar disc surgery: a randomized controlled trial.
A prospective and controlled study of perioperative use of combined local anesthetic and corticosteroid in lumbar disc surgery. The anti-inflammatory mechanism of corticosteroids is considered to be caused by the inhibition of phospholipase A2, which plays an important role in the pain mechanism of lumbar disc problems. Although some authors have demonstrated that the use of intramuscular bupivacaine during lumbar discectomy resulted in a marked reduction of postoperative back pain, others have reported that the key intervention was probably the administration of epidural corticosteroid. The coadministration of these two drugs in lumbar disc surgery for the relief of postoperative back pain has yet not been studied adequately. Assessment of the combined use of perioperative corticosteroids and bupivacaine for the relief of postoperative pain after lumbar disc surgery. Forty-four selected patients had acute-onset single-level unilateral herniated nucleus pulposus that were refractory to conservative management. All patients underwent lumbar disc surgery under standard general anesthesia. Before surgical incision, the skin and subcutaneous tissues were infiltrated with 10 mL of 1% lidocaine with 1:200,000 adrenaline to produce local vasoconstriction. During wound closure, 20 mL 0.9% saline in Group 1 (n = 22) and 20 mL 0.25% bupivacaine in Group 2 (n = 22) were injected into the paravertebral muscles and subcutaneus tissues. In addition, a piece of autologous fat taken from the wound was first soaked in 40 mg of methylprednisolone for 10 minutes, then placed over the exposed nerve root, and the remaining steroid was flushed into the wound in Group 2. The wound was closed after drug administration in both groups. In the postoperative period, all patients received 100 mg of meperidine intramuscularly when needed and were allowed to receive a second dose at least 4 hours later than the first dose for postoperative analgesia. Postoperative back pain intensity, heart rate, and mean arterial pressure were assessed 1, 3, 6, and 12 hours after the conclusion of surgery. Visual analog scale pain scores for the postoperative recordings were lower in Group 2 than in Group 1, but these findings were not statistically significant. Patients in Group 1 received 77.3 +/- 48.8 mg meperidine, and those in Group 2 received 31.8 +/- 45.5 mg meperidine, for pain medication in the first 12 hours (P < 0.05). Heart rate and mean arterial pressure were not significantly different between the two groups in all recording periods. It is concluded that the perioperative use of bupivacaine and corticosteroids during lumbar discectomy maintains effective postoperative analgesia and decreases opioid usage without complications. |
[The application research of eustachian tuboplasty assisted with hypothermy plasma ablation in the threatment of adult refractory otitis media with effusion].
Through the application of eustachian tuboplasty assisted with hypothermy plasma ablation, we evaluate its efficacy in the threatment of adult refractory otitis media with effusion. We retrospectively reviewed the charts of 48 cases (61 ears) suffering from adult refractory otitis media with effusion from January 2012 to December 2013. According to the admission date, the patients were divided into the control group (17 cases, 22 ears) and the treatment group (31 cases, 39 ears). In the control group, the patients were treated with drugs and physical therapy. In the treatment group, the hypothermy plasma ablation technology was used to ablates the hypertrophic tissues around the eustachian orifice besides the pharmaedogical interventions. The recurrence rate of the two groups were analyzed and compared in 1 year after treatment. Pure tone audiometry and acoustic immittance measurement were taken for the two groups in differernt periods (one week prior to operation, one months, three months, six months and one year after operation respectively) to evaluate their hearing change and the recurrence rate (within six months after treatment and one year respectively) objectively. In the control group, 2 cases (2 ears) were lost to follow-up, and the recurrence rate was 65% (13/20) in 1 year. In the treatment group, four case were lost to follow-up,and the recurrence rate was 14.3% (5/35) in 1 year. The difference was statistically significant (P<0. 01). There were similar hearing improvement in the two groups after treatment in 1 month, but the hearing improvement in the treatment group increased with time. There were no complications occuring during the operation and post-operation. Within a month after operation, the majority of ears(28/35) obtained significant hearing improvement with the decreasing air-bone-gap comparision with the pre-operation (P < 0.01), and the preoperative tympanogram of 16 ears with type B or C turned to type A (P < 0.01). There were no both statistical significance in the variation of air-bone-gap and tympanogram of comparison with results between three months and six months, six months and one year postoperatively (P > 0.05). This study confirmed the efficacy of eustachian tuboplasty assisted with hypothermy plasma ablation in the threatment of adult refractory otitis media with effusion caused by eustachian tube opening disorder was significant. It can reduce the recurrence rate significantly in one year and allow sustained hearing improvement within three months postoperatively. |
Monogenic and polygenic determinants of sarcoma risk: an international genetic study.
Sarcomas are rare, phenotypically heterogeneous cancers that disproportionately affect the young. Outside rare syndromes, the nature, extent, and clinical significance of their genetic origins are not known. We aimed to investigate the genetic basis for bone and soft-tissue sarcoma seen in routine clinical practice. In this genetic study, we included 1162 patients with sarcoma from four cohorts (the International Sarcoma Kindred Study [ISKS], 966 probands; Project GENESIS, 48 probands; Asan Bio-Resource Center, 138 probands; and kConFab, ten probands), who were older than 15 years at the time of consent and had a histologically confirmed diagnosis of sarcoma, recruited from specialist sarcoma clinics without regard to family history. Detailed clinical, pathological, and pedigree information was collected, and cancer diagnoses in probands and relatives were independently verified. Targeted exon sequencing using blood (n=1114) or saliva (n=48) samples was done on 72 genes (selected due to associations with increased cancer risk) and rare variants were stratified into classes approximating the International Agency for Research on Cancer (IARC) clinical classification for genetic variation. We did a case-control rare variant burden analysis using 6545 Caucasian controls included from three cohorts (ISKS, 235 controls; LifePool, 2010 controls; and National Heart, Lung, and Blood Institute Exome Sequencing Project [ESP], 4300 controls). The median age at cancer diagnosis in 1162 sarcoma probands was 46 years (IQR 29-58), 170 (15%) of 1162 probands had multiple primary cancers, and 155 (17%) of 911 families with informative pedigrees fitted recognisable cancer syndromes. Using a case-control rare variant burden analysis, 638 (55%) of 1162 sarcoma probands bore an excess of pathogenic germline variants (combined odds ratio [OR] 1·43, 95% CI 1·24-1·64, p<0·0001), with 227 known or expected pathogenic variants occurring in 217 individuals. All classes of pathogenic variants (known, expected, or predicted) were associated with earlier age of cancer onset. In addition to TP53, ATM, ATR, and BRCA2, an unexpected excess of functionally pathogenic variants was seen in ERCC2. Probands were more likely than controls to have multiple pathogenic variants compared with the combined control cohort group and the LifePool control cohort (OR 2·22, 95% CI 1·57-3·14, p=1·2 × 10(-6)) and the cumulative burden of multiple variants correlated with earlier age at cancer diagnosis (Mantel-Cox log-rank test for trend, p=0·0032). 66 of 1162 probands carried notifiable variants following expert clinical review (those recognised to be clinically significant to health and about which patients should be advised), whereas 293 (25%) probands carried variants with potential therapeutic significance. About half of patients with sarcoma have putatively pathogenic monogenic and polygenic variation in known and novel cancer genes, with implications for risk management and treatment. Rainbows for Kate Foundation, Johanna Sewell Research Foundation, Australian National Health and Medical Research Council, Cancer Australia, Sarcoma UK, National Cancer Institute, Liddy Shriver Sarcoma Initiative. |
[Analysis of short-term therapeutic efficacy of integrated traditional and Western medicine in treating non-small cell lung cancer].
To observe the short-term therapeutic efficacy of integrated traditional and Western medicine (ITWM) in treating non-small cell lung cancer (NSCLC) in III and IV phase. Adopting the prospective, multi-centered, randomized and controlled method for clinical research, 324 patients who conformed to the enrolling standard were divided by ratio of 1:1:1 into the Chinese medicine (CM) group (n= 99), the ITWM group (n 03) and the Western medicine (WM) (n=92) group. The excluded or dropping off cases were 10 in CM, 6 in ITWM and 14 in WM. Clinical trials were conducted in 6 hospitals and 3 months of treatment was taken as one therapeutic course. The main observation indexes were tumor size, Karnofsky scores, body weight, adverse reaction, etc. The total effective rate of tumor remission in the 3 groups was 4.0%, 26.2%, and 14.1%, respectively, statistical significance was shown in the difference among them (chi = 21.72, P = 0.000 < 0.017). The total tumor stabilization rate was 66.7 , 81.6%, and 76.1 , respectively, by rectification test, no significance was shown in difference among them (chi2 = 6.052, P = 0.049 > 0.017). Karnofsky scoring showed that after 90 days of treatment, Karnofsky score raised in the CM and ITWM group, but lowered in the WM group, paired t-test showed significant difference in the ITWM group before and after treatment. The Karnofsky score in IWTM was higher than that in CM and WM with significant difference (H = 10.572, P = 0.000 < 0.05). The patients' body weight in the 3 groups were all reduced. The reduction in the CM and ITWM group was lower than that in WM group, among which, significant difference was shown in CM and WM group when compared with the same group before treatment (P < 0.05). The effect in the ITWM and CM group was better than that in WM group in aspects of improving such tumor related symptoms as cough, short breath, anorexia, fatigue, etc. Observation of adverse reaction showed that lesser hemotoxicity of III and IV grade appeared in the CM and ITWM group than that in the WM group, and significant difference was shown in counts of white blood cells, granulocytes, platelets hemoglobin, etc. among the 3 groups (P < 0.01). ITWM therapy showed better short-term efficacy in treating patients with NSCLC than CM or WM alone, showing the superiority of ITWM therapy. It can be adopted as an effective therapeutic program with low-toxicity. |
Suramin-induced decrease in prostate-specific antigen expression with no effect on tumor growth in the LNCaP model of human prostate cancer.
Suramin, a polysulfonated naphthylurea and a recognized antitrypanosomal agent, has shown some promise in phase II clinical trials in the management of hormone-refractory human prostate cancer. Reduction of serum prostate-specific antigen (PSA) levels has been proposed as an end point for evaluating the antitumor efficacy of treatments for hormone-refractory prostate cancer. We examined the antitumor effect of suramin in an in vivo mouse model of hormone-refractory human prostate cancer to determine whether a decrease in PSA levels reflects a reduction in tumor growth (volume). The tumors were induced in castrated, athymic nude mice by use of the androgen-independent, tumorigenic human prostate cancer cell line C4-2, which is a subline of the androgen-dependent, parental nontumorigenic cell line LNCaP. We also evaluated the effects of suramin in vitro on cell growth and the expression of PSA messenger RNA (mRNA) in both LNCaP and C4-2 cells. For the in vivo studies, 24 mice were given a subcutaneous injection of 5 x 10(6) C4-2 cells at each of four sites. Animals (n = 20) with tumor volumes greater than 1 mm3 or less than 5 mm3 were divided equally into two groups. Drug treatment was initiated in one group by administration of 1 mg suramin intraperitoneally, followed by 0.1 mg suramin at 10-day intervals to maintain constant serum levels. Tumor growth and PSA expression levels were monitored. For the in vitro studies, both LNCaP and C4-2 cells were exposed to 100-400 microgram/mL suramin, and cell growth was monitored by a quantitative crystal violet assay. PSA mRNA expression was assessed by northern blot analysis in cells treated with either 250 microgram/mL suramin, 400 ng/mL dihydrotestosterone (DHT) (positive control), or 0.5-75 microgram/mL hydrocortisone (to mimic the clinical use of hydrocortisone during suramin treatment to compensate for the loss of adrenocortical function). In some studies, the combined effect of DHT and suramin on PSA mRNA expression was also evaluated. A two-way analysis of variance was performed to evaluate the treatment differences, and P values were obtained from two-sided tests for statistical significance. In vivo, suramin did not significantly affect the growth of androgen-independent C4-2 tumors (relative to the growth of tumors in 5% glucose-treated control animals; P = .76). However, suramin significantly decreased the ratio of PSA level to tumor volume (ng/mL PSA per mm(3) of tumor) (P<.001). Mice developed bone metastases in both treatment arms. Suramin affected the in vitro growth of LNCaP cells but not of C4-2 cells. Suramin diminished PSA mRNA expression in both LNCaP and C4-2 cells grown in vitro. Hydrocortisone had no effect on PSA mRNA levels. Although suramin inhibited the growth of androgen-dependent LNCaP cells, it did not inhibit the growth of androgen-independent C4-2 cells either in vitro or in vivo. Suramin significantly decreased PSA mRNA expression in both cell lines in vitro and depressed serum PSA levels in mice bearing androgen-independent C4-2 tumors. PSA level should be used with caution as an end point in clinical trials using suramin therapy for hormone-refractory prostate cancer. |
The kinetics of murine hematopoietic stem cells in vivo in response to prolonged increased mature blood cell production induced by granulocyte colony-stimulating factor.
Because of the complexity of appropriate stem cell assays, little information on the in vivo regulation of murine stem cell biology or stemmatopoiesis is available. It is unknown whether and how in vivo the primitive hematopoietic stem cell compartment is affected during a continued increased production of mature blood cells. In this study, we present data showing that prolonged (3 weeks) administration of granulocyte colony-stimulating factor (G-CSF), which is a major regulator of mature granulocyte production, has a substantial impact on both the size and the location of various stem cell subset pools in mice. We have used the novel cobblestone area forming cell (CAFC) assay to assess the effects of G-CSF on the stem cell compartment (CAFC days 7, 14, 21, and 28). In marrow, in which normally 99% of the total number of stem cells can be found, G-CSF induced a severe depletion of particularly the most primitive stem cells to 5% to 10% of normal values. The response after 7 days of G-CSF treatment was an increased amplification between CAFC day 14 and 7. However, this response occurred at the expense of the number of CAFC day 14. It is likely that the resulting gap of CAFC day 14 cell numbers was subsequently replenished from the more primitive CAFC day 21 and 28 compartments, because these cell numbers remained low during the entire treatment period. In the spleen, the number of stem cells increased, likely caused by a migration from the marrow via the blood, leading to an accumulation in the spleen. The increased number of stem cells in the spleen overcompensated for the loss in the marrow. When total body (marrow and spleen) stem cell numbers were calculated, it appeared that a continued increased production of mature granulocytes resulted in the establishment of a higher, new steady state of the stem cell compartment; most committed stem cells (CAFC day 7) were increased threefold, CAFC day 14 were increased 2.3-fold, CAFC-day 21 were increased 1.8-fold, and the most primitive stem cells evaluated, CAFC day 28, were not different from normal, although now 95% of these cells were located in the spleen. Four weeks after discontinuation of the G-CSF treatment, the stem cell reserve in the spleen had returned to a normal level, whereas stem cell numbers in marrow had recovered to values above normal. This study shows that the primitive stem cell compartment is seriously perturbed during an increased stimulation of the production of mature blood cells.(ABSTRACT TRUNCATED AT 400 WORDS) |
Chemotherapy, irradiation, and surgery for function-preserving therapy of primary extremity soft tissue sarcomas: initial treatment with ifosfamide, mitomycin, doxorubicin, and cisplatin plus granulocyte macrophage-colony-stimulating factor.
Most institutional teams utilize multimodality therapy in their efforts to cure patients with primary high-grade extremity soft tissue sarcomas, although the value of adjuvant systemic chemotherapy is still disputed by some oncologists. This single-institution Phase II study describes an effort to control metastasis by the use of two cycles of chemotherapy as the initial preoperative treatment. Between March 1994 and October 1997, 20 women and 19 men with primary extremity or limb girdle high-grade soft tissue sarcomas were registered to a study of preoperative ifosfamide, mitomycin, doxorubicin, cisplatin (IMAP) plus granulocyte macrophage-colony-stimulating factor (GM-CSF) followed by preoperative irradiation and subsequent limb-sparing surgery. The two sequential monthly cycles of IMAP involved intravenous ifosfamide, 2500 mg/m(2), and mesna, 2500 mg/m(2), on Day 0, followed by identical doses of these agents plus intravenous mitomycin, 4 mg/m(2), doxorubicin, 40 mg/m(2), and cisplatin, 60 mg/m(2), on Day 1. Sargramostim (GM-CSF) 250 microg/m(2) was given subcutaneously every 12 hours for 4 days beginning 6 days before the chemotherapy, and then for 14 more days beginning the day after chemotherapy was completed. At the beginning of the third month, external beam irradiation was administered daily, 5 days each week for 5 consecutive weeks to total preoperative doses of 4500 centigrays (cGy). This was accompanied by reduced doses of MAP chemotherapy (mitomycin, 6 mg/m(2), doxorubicin, 30 mg/m(2), and cisplatin, 45 mg/m(2)) intravenously on Days 0, 21, and 42 of the radiation therapy segment. Approximately 1 month after preoperative irradiation ended, each patient had complete surgical excision with curative intent, using limb-sparing techniques when possible. Radiation to total doses of 5500-6500 cGy was accomplished by delivery of an additional 1000-2000 cGy to the tumor bed via intraoperative electron beam, brachytherapy, or external beam irradiation at the completion of surgery. All except 5 patients had tumors at least 5 cm in diameter. Chemotherapy toxicity grade three or higher consisted primarily of vomiting (23%), leukopenia (54%), and thrombocytopenia (77%). Six patients have died of metastatic sarcoma, and one other died in a motorcycle accident. Kaplan-Meier curves indicate estimated 5-year survival of approximately 80% and freedom from metastasis at 2 years of approximately 85%. IMAP plus GM-CSF is satisfactory as initial treatment for primary extremity soft tissue sarcomas in two monthly cycles preceding irradiation. The prescribed irradiation was generally tolerable and effective in permitting limb-sparing surgery. Although the outcome of patients treated on this regimen has been favorable, the metastasis problem has not been eliminated. |
Risk of perinatal death associated with labor after previous cesarean delivery in uncomplicated term pregnancies.
Trial of labor after previous cesarean delivery is associated with increased risk of uterine rupture. However, no reliable data exist on the effect of a trial of labor on the risk of perinatal death in otherwise uncomplicated term pregnancies. To determine the risk of intrapartum stillbirth or neonatal death not related to congenital abnormality among women with uncomplicated term pregnancies who had a trial of labor after previous cesarean delivery, compared with women having a planned repeat cesarean delivery, and multiparous and nulliparous women at term not delivered by planned cesarean method. Population-based, retrospective cohort study of data from the linked Scottish Morbidity Record and Stillbirth and Neonatal Death Enquiry encompassing births in Scotland between January 1, 1992, and December 31, 1997. A total of 313 238 singleton births between 37 and 43 weeks' gestational age in which the fetus was in a cephalic presentation. Delivery-related perinatal death, defined as intrapartum stillbirth or neonatal death unrelated to congenital anomaly, compared among the 4 groups. Among women who had a trial of labor following previous cesarean delivery (n = 15 515), the overall rate of delivery-related perinatal death was 12.9 (95% confidence interval [CI], 7.9-19.9) per 10 000 women. This was approximately 11 times greater (odds ratio [OR], 11.6; 95% CI, 1.6-86.7) than the risk associated with planned repeat cesarean delivery (n = 9014), more than twice (OR, 2.2; 95% CI, 1.3-3.5) the risk associated with other multiparous women in labor (n = 151 549), and similar to the risk among nulliparous women in labor (n = 137 160; OR, 1.3; 95% CI, 0.8-2.1). The associations were not explained by differences in maternal height, smoking status, socioeconomic status, age, fetal growth, or week of gestation at delivery. Among women having a trial of labor, the rate of death due to mechanical causes, including uterine rupture, was 4.5 (95% CI, 1.8-9.3) per 10 000 women. This was more than 8 times greater than other multiparous women (OR, 8.5; 95% CI, 3.2-22.3) and nulliparous women (OR, 8.8; 95% CI, 3.2-24.2). The absolute risk of perinatal death associated with trial of labor following previous cesarean delivery is low. However, in our study, the risk was significantly higher than that associated with planned repeat cesarean delivery, and there was a marked excess of deaths due to uterine rupture compared with other women in labor. |
Determinants of patient satisfaction in postmastectomy breast reconstruction.
In today's increasingly competitive health care marketplace, consumer satisfaction has become an important measure of quality. Furthermore, measures of satisfaction with treatment inteerventions are influential factors in determining patients' and payers' choices of health care. This study sought to evaluate satisfaction with postmastectomy breast reconstruction and to assess the effects of procedure type and timing on patient satisfaction. As part of the Michigan Breast Reconstruction Outcome Study, patients undergoing first-time mastectomy reconstruction were prospectively evaluated, including cohorts of women choosing expander/implant, pedicle TRFAM flap, and free TRAM flap procedures. Preoperatively and 1 year postoperatively, participants completed a questionnaire that collected a variety of health status information. The postoperative questionnaire had an additional seven items assessing both general satisfaction with reconstruction (five items) and aesthetic satisfaction (two items) as separate subscales. Patients were asked to respond to each item using a five-point Likert scale. Item responses ranged from 1, indicating high satisfaction, to 5, reflecting low satisfaction. In the data analysis, only patients responding with a 1 or 2 for all of the items within a subscale were classified as "satisfied" for the subscale. To assess the effects of procedure type (implant, pedicle TRAM flap, and free TRAM flap) and timing (immediate versus delayed) on satisfaction and to control for possible confounding effects from other independent variables, multiple logistic regression was employed. In our analysis, odds ratios and associated 95 percent confidence intervals were calculated for each independent variable in the regression. Statistical significance was designated at the p < or = 0.05 level. A total of 212 patients were followed during the period of 1994 to 1997, including 141 immediate and 71 delayed reconstructions. The study population consisted of 49 expander/implant, 102 pedicle TRAM flap, and 61 free TRAM flap reconstruction patients. The analysis showed a significant association between procedure type and patient satisfaction. TRAM flap patients (both free and pedicle) appeared to have significantly greater general and aesthetic satisfaction compared with expander/implant patients (p = 0.03 and 0.001, respectively). Furthermore, pedicle TRAM flap patients were more aesthetically satisfied than those with free TRAM flaps (p = 0.072). The other independent variables of age and procedure timing did not appear to significantly affect either general or aesthetic satisfaction. However, preoperative physical activity was positively correlated with general satisfaction at the p = 0.034 level. The choice of procedure seems to have a significant effect on both aesthetic and general patient satisfaction with breast reconstruction. In this study, autogenous tissue reconstructions produced higher levels of patient aesthetic and general satisfaction compared with implant techniques. Pedicle and free TRAM flap patients do not seem to differ significantly in general satisfaction. However, women receiving pedicle TRAM flaps reported greater aesthetic satisfaction compared with patients undergoing free TRAM flaps. Furthermore, patient age and procedure timing may not have an effect on patient satisfaction with breast reconstruction. |
An attempt to understand glioma stem cell biology through centrality analysis of a protein interaction network.
Biological networks can be analyzed using "Centrality Analysis" to identify the more influential nodes and interactions in the network. This study was undertaken to create and visualize a biological network comprising of protein-protein interactions (PPIs) amongst proteins which are preferentially over-expressed in glioma cancer stem cell component (GCSC) of glioblastomas as compared to the glioma non-stem cancer cell (GNSC) component and then to analyze this network through centrality analyses (CA) in order to identify the essential proteins in this network and their interactions. In addition, this study proposes a new centrality analysis method pertaining exclusively to transcription factors (TFs) and interactions amongst them. Moreover the relevant molecular functions, biological processes and biochemical pathways amongst these proteins were sought through enrichment analysis. A protein interaction network was created using a list of proteins which have been shown to be preferentially expressed or over-expressed in GCSCs isolated from glioblastomas as compared to the GNSCs. This list comprising of 38 proteins, created using manual literature mining, was submitted to the Reactome FIViz tool, a web based application integrated into Cytoscape, an open source software platform for visualizing and analyzing molecular interaction networks and biological pathways to produce the network. This network was subjected to centrality analyses utilizing ranked lists of six centrality measures using the FIViz application and (for the first time) a dedicated centrality analysis plug-in ; CytoNCA. The interactions exclusively amongst the transcription factors were nalyzed through a newly proposed centrality analysis method called "Gene Expression Associated Degree Centrality Analysis (GEADCA)". Enrichment analysis was performed using the "network function analysis" tool on Reactome. The CA was able to identify a small set of proteins with consistently high centrality ranks that is indicative of their strong influence in the protein protein interaction network. Similarly the newly proposed GEADCA helped identify the transcription factors with high centrality values indicative of their key roles in transcriptional regulation. The enrichment studies provided a list of molecular functions, biological processes and biochemical pathways associated with the constructed network. The study shows how pathway based databases may be used to create and analyze a relevant protein interaction network in glioma cancer stem cells and identify the essential elements within it to gather insights into the molecular interactions that regulate the properties of glioma stem cells. How these insights may be utilized to help the development of future research towards formulation of new management strategies have been discussed from a theoretical standpoint. |
Effects of calcitonin gene-related peptide on apoptosis of peripheral blood mononuclear cells from patients with systemic lupus erythematosus.
Systemic lupus erythematosus (SLE) is an autoimmune disease with abnormal apoptosis and autoantibody production. Calcitonin gene-related peptide (CGRP) is a neuropeptide produced by the central and peripheral nervous systems and by endocrine cells. It can influence cell death in thymocytes and cultured smooth muscle cells, and inhibits the production of interleukin (IL)-2, which inhibits apoptosis. To investigate the effects of calcitonin gene-related peptide (CGRP) on apoptosis of peripheral blood mononuclear cells (PBMCs) from patients with SLE. The percentage of apoptosis of PBMCs from patients with SLE and healthy blood donors were examined using annexin-V/propidine iodide staining 48 h after culturing with CGRP and/or its receptor antagonist CGRP(8-37) at various concentrations. IL-2 activity in culture supernatants was determined using the incorporation of 3H-TdR by the IL-2-dependent cell line CTLL and evaluated by ELISA. The percentage of spontaneous apoptosis of PBMCs from patients with SLE was higher than that of healthy blood donors (34.18 +/- 2.86 vs. 18.23 +/- 0.81, P < 0.001). CGRP, at all tested concentrations, had no effect on apoptosis of PBMCs from healthy blood donors, but significantly inhibited apoptosis of PBMCs from patients with SLE at concentrations of >or= 0.5 x 10(-8) mol/L (0.5 x 10(-8) mol/L: 32.01 +/- 3.98 vs. 34.18 +/- 2.86, P < 0.05; 1.0 x 0(-8) mol/L: 26.76 +/- 2.69 vs. 34.18 +/- 2.86, P < 0.001; 1.5 x 10(-8) mol/L: 25.97 +/- 2.65 vs. 34.18 +/- 2.86, P < 0.001), and the effect plateaued at 1.0 x 10(-8) mol/L, at which level inhibition was not significantly increased with increasing concentration. However, CGRP, at any concentration tested, could not reduce the rate of apoptosis of PBMCs from patients with SLE to the normal range. There were significant positive relationships between the effect of CGRP, on apoptosis of PBMCs and SLE Disease Activity Index (0.5 x 10(-8) mol/L: r(s) = 0.328, P < 0.05; 1.0 x 10(-8) mol/L: r(s) = 0.431, P < 0.01; 1.5 x 10(-8) mol/L: r(s) = 0.419, P < 0.01). CGRP(8-37) itself had no effect on apoptosis, but was able to block the effects of CGRP on PBMCs (0.5 x 10(-8) mol/L: 32.01 +/- 3.98 vs. 33.12 +/- 2.37, P < 0.05; 1.0 x 10(-8) mol/L: 26.76 +/- 2.69 vs. 34.73 +/- 2.32, P < 0.001; 1.5 x 10(-8) mol/L: 25.97 +/- 2.65 vs. 35.25 +/- 3.37, P < 0.001). There was no effect of CGRP on IL-2 production. These results indicate that CGRP plays an important role in the apoptosis of PBMCs from patients with SLE via its receptor; low plasma levels of CGRP may cause accelerated apoptosis. This regulation does not seem to be related to IL-2. |
[Resident dietary exposure of cadmium in Jiangsu province].
To investigate the resident dietary cadmium exposure in Jiangsu province and assess its safety. Cadmium concentration of 229 food items under 12 food groups were obtained from the food surveillance program in Jiangsu province between 2001 and 2006. Food consumption data of 778 food items of 3938 residents who were classified into four age groups (< 7, 7-, 13-, 18-) were got from the Nutrition and Health Status Survey of the Jiangsu resident in 2002 by 24 h dietary recall on three consecutive days. Dietary cadmium exposures for the residents of different age groups were obtained by using both point estimation and simple distribution estimation through integrating the two datasets above. The safety of dietary cadmium exposure was assessed. Point estimation showed that the average dietary cadmium intakes of different age groups ranged from 5.7 to 8.6 microg/kg, accounting for 567.1% - 857.1% of the provisional tolerable daily intake (PTDI, 1.0 microg/kg). Result of simple distribution method showed mean daily cadmium exposure of different age groups ranged from 0.2 to 0.4 microg/kg, accounting for 20% - 40% of PTDI. Mean weekly cadmium exposure ranged from 1.4 to 2.5 microg/kg, accounting for 20% - 35.7% of the provisional tolerable weekly intake (PTWI, 7.0 microg/kg). The mean daily dietary cadmium exposure for different groups were as follows: < 7, 0.4 microg/kg; 7-, 0.3 microg/kg; 13-, 0.2 microg/kg; 18-, 0.2 microg/kg. Differences of daily dietary cadmium exposures among groups were significant (F = 69.0, P < 0.05). The mean weekly dietary cadmium exposure for different groups were: < 7, 2.5 microg/kg; 7-, 2.0 microg/kg; 13-, 1.4 microg/kg; 18-, 1.4 microg/kg. Differences of weekly dietary cadmium exposures among groups were also significant (F = 41.6, P < 0.05). The P97.5 of daily cadmium exposure for < 7 and 7- were 1.4 and 1.2 microg/kg, respectively, both of which were higher than PTDI. The P99.0 of daily cadmium exposure for 13- and 18- were 1.3 and 1.1 microg/kg, respectively. The daily dietary exposure from cereals for different age groups were 21.5 - 253.4 microg/kg, occupying 42.2% - 47.8% of the total daily exposure. Vegetables were 8.0 - 119.4 microg/kg, occupying 14.6% - 20.1%. The average level of dietary cadmium exposures for residents in Jiangsu province calculated by simple distribution estimation were much lower than that calculated by point estimation and were considered to be at no risk. P97.5 or P99.0 of daily or weekly dietary cadmium exposure of different age groups exceeded PTWI and PTDI. The main food types of dietary cadmium exposure were cereals and vegetables. |
Multivalent ligand-receptor binding interactions in the fibroblast growth factor system produce a cooperative growth factor and heparin mechanism for receptor dimerization.
The binding interactions for the three primary reactants of the fibroblast growth factor (FGF) system, basic FGF (bFGF), an FGF receptor, FGFR1, and the cofactor heparin/heparan sulfate (HS), were explored by isothermal titrating calorimetry, ultracentrifugation, and molecular modeling. The binding reactions were first dissected into three binary reactions: (1) FGFR1 + bFGF<==>FGFR1/bFGF, K1 = 41 (+/- 12) nM; (2) FGFR1 + HS<==>FGFR1/HS, K2 = 104 (+/- 17) microM; and (3) bFGF + HS<==>bFGF/HS, K3 = 470 (+/- 20) nM, where HS = low MW heparin, approximately 3 kDa. The first, binding of bFGF to FGFR1 in the absence of HS, was found to be a simple binary binding reaction that is enthalpy dominated and characterized by a single equilibrium constant, K1. The conditional reactions of bFGF and FGFR1 in the presence of heparin were then examined under conditions that saturate only the bFGF heparin site (1.5 equiv of HS/bFGF) or saturate the HS binding sites of both bFGF and FGFR1 (1.0 mM HS). Both 3-and 5-kDa low MW heparins increased the affinity for FGFR1 binding to bFGF by approximately 10-fold (Kd = 4.9 +/- 2.0 nM), relative to the reaction with no HS. In addition, HS, at a minimum of 1.5 equiv/bFGF, induced a second FGFR1 molecule to bind to another lower affinity secondary site on bFGF (K4 = 1.9 +/- 0.7 microM) in an entropy-dominated reaction to yield a quaternary complex containing two FGFR1, one bFGF, and at least one HS. Molecular weight estimates by analytical ultracentrifugation of such fully bound complexes were consistent with this proposed composition. To understand these binding reactions in terms of structural components of FGFR1, a three-dimensional model of FGFR1 was constructed using segment match modeling. Electrostatic potential calculations confirmed that an elongated cluster, approximately 15 x 35 A, of nine cationic residues focused positive potential (+2kBT) to the solvent-exposed beta-sheet A, B, E, C' surface of the D(II) domain model, strongly implicating this locus as the HS binding region of FGFR1. Structural models for HS binding to FGFR1, and HS binding to bFGF, were built individually and then assembled to juxtapose adjacent binding sites for receptor and HS on bFGF, against matching proposed growth factor and HS binding sites on FGFR1. The calorimetric binding results and the molecular modeling exercises suggest that bFGF and HS participate in a concerted bridge mechanism for the dimerization of FGFR1 in vitro and presumably for mitogenic signal transduction in vivo.(ABSTRACT TRUNCATED AT 400 WORDS) |
Two-level corpectomy versus three-level discectomy for cervical spondylotic myelopathy: a comparison of perioperative, radiographic, and clinical outcomes.
In the treatment of cervical spondylotic myelopathy (CSM), anterior cervical corpectomy and fusion (ACCF) and anterior cervical discectomy and fusion (ACDF) are effective decompressive techniques. It remains to be determined whether ACCF and ACDF offer equivalent outcomes for multilevel CSM. In this study, the authors compared perioperative, radiographic, and clinical outcomes between 2-level ACCF and 3-level ACDF. Between 2006 and 2012, all patients at the authors' hospital who underwent 2-level ACCF or 3-level ACDF performed by 1 of 2 surgeons were identified. Primary outcomes of interest were sagittal Cobb angle, adjacent-segment disease (ASD) requiring surgery, neck pain measured by visual analog scale (VAS), and Nurick score. Secondary outcomes of interest included estimated blood loss (EBL), length of stay, perioperative complications, and radiographic pseudarthrosis rate. Chi-square tests and 2-tailed Student t-tests were used to compare the 2 groups. A subgroup analysis of patients without posterior spinal fusion (PSF) was also performed. Twenty patients underwent 2-level ACCF, and 35 patients underwent 3-level ACDF during a 6-year period. Preoperative Nurick scores were higher in the ACCF group (2.1 vs 1.1, p = 0.014), and more patients underwent PSF in the 2-level ACCF group compared with patients in the 3-level ACDF group (60.0% vs 17.1%, p = 0.001). Otherwise there were no significant differences in demographics, comorbidities, and baseline clinical parameters between the 2 groups. Two-level ACCF was associated with significantly higher EBL compared with 3-level ACDF for the anterior stage of surgery (382.2 ml vs 117.9 ml, p < 0.001). Two-level ACCF was also associated with a longer hospital stay compared with 3-level ACDF (7.2 days vs 4.9 days, p = 0.048), but a subgroup comparison of patients without PSF showed no significant difference in length of stay (3.1 days vs 4.4 days for 2-level ACCF vs 3-level ACDF, respectively; p = 0.267). Similarly, there was a trend toward more complications in the 2-level ACCF group (20.0%) than the 3-level ACDF group (5.7%; p = 0.102), but a subgroup analysis that excluded those who had second-stage PSF no longer showed the same trend (2-level ACCF, 0.0% vs 3-level ACDF, 3.4%; p = 0.594). There were no significant differences between the ACCF group and the ACDF group in terms of postoperative sagittal Cobb angle (7.2° vs 12.1°, p = 0.173), operative ASD (6.3% vs 3.6%, p = 0.682), and radiographic pseudarthrosis rate (6.3% vs 7.1%, p = 0.909). Both groups had similar improvement in mean VAS neck pain scores (3.4 vs 3.2 for ACCF vs ACDF, respectively; p = 0.860) and Nurick scores (0.8 vs 0.7, p = 0.925). Two-level ACCF was associated with greater EBL and longer hospital stays when patients underwent a second-stage PSF. However, the length of stay was similar when patients underwent anterior-only decompression with either 2-level ACCF or 3-level ACDF. Furthermore, perioperative complication rates were similar in the 2 groups when patients underwent anterior decompression without PSF. Both groups obtained similar postoperative cervical lordosis, operative ASD rates, radiographic pseudarthrosis rates, neurological improvement, and pain relief. |
Application of selection index calculations to determine selection strategies in genomic breeding programs.
The availability of genomic estimated breeding values (GEBV) allows for possible modifications to existing dairy cattle breeding programs. Selection index calculations including genomic and phenotypic observations as index sources were used to determine the optimal number of offspring per genotyped sire with a focus on functional traits and the design of cooperator herds, and to evaluate the importance of a central station test for genotyped bull dams. Evaluation criteria to compare different breeding strategies were correlations between index and aggregate genotype (r(TI)), and the relative selection response percentage (RSR) of an index without single nucleotide polymorphism information in relation to a single nucleotide polymorphism-based index. The number of required daughter records per sire to achieve a predefined r(TI) strongly depends on the accuracy of GEBV (r(mg)) and the heritability of the trait. For a desired r(TI) of 0.8, h(2) = 0.10, and r(mg) = 0.5, at least 57 additional daughters have to be included in the genetic evaluation. Daughter records of genotyped sires are not necessary for optimal scenarios where r(mg) is greater than or equal to r(TI). There still is a substantial need for phenotypic daughter records, especially for low-heritability functional traits and r(mg) < 0.7. Phenotypic records from genotyped potential bull dams have no relevance for increasing r(TI), even with a low value for r(mg) of 0.5. Hence, genomic breeding programs should focus on recording functional traits within progeny groups, preferably in cooperator herds. For low-heritability traits and with r(mg) > 0.7, the RSR of conventional breeding programs was only 10% of RSR from genomic breeding strategies. As shown in scenarios including 2 traits in the index as well as in the aggregate genotype, the availability of highly accurate GEBV for production traits and low-accuracy GEBV for functional traits increased the risk of widening the gap between selection responses in production and functionality. Counteractions are possible, such as via higher economic weights for low-heritability functional traits. Finally, an alternative selection strategy considering only 2 pathways of selection for genotyped male calves and for cow dams was evaluated. This strategy is competitive with a 4-pathway genomic breeding program if the fraction of selected male calves for the artificial insemination program is below 1% and if selection is focused on functionality, thus pointing to substantial insufficiencies caused by low reliabilities of breeding values for cows for such traits in conventional bull dam selection schemes. |
Theoretical study of oxygen adsorption on pure Au(n+1)+ and doped MAu(n)+ cationic gold clusters for M = Ti, Fe and n = 3-7.
A comparative study of the adsorption of an O2 molecule on pure Au(n+1)+ and doped MAu(n)+ cationic gold clusters for n = 3-7 and M = Ti, Fe is presented. The simultaneous adsorption of two oxygen atoms also was studied. This work was performed by means of first principles calculations based on norm-conserving pseudo-potentials and numerical basis sets. For pure Au4 +, Au6+, and Au7+ clusters, the O2 molecule is adsorbed preferably on top of low coordinated Au atoms, with an adsorption energy smaller than 0.5 eV. Instead, for Au5+ and Au8+, bridge adsorption sites are preferred with adsorption energies of 0.56 and 0.69 eV, respectively. The ground-state geometry of Au(n)+ is almost unperturbed after O2 adsorption. The electronic charge flows towards O2 when the molecule is adsorbed in bridge positions and towards the gold cluster when O2 is adsorbed on top of Au atoms, and both the adsorption energy and the O-O bond length of adsorbed oxygen increase when the amount of electronic charge on O2 increases. On the other hand, we studied the adsorption of an O2 molecule on doped MAu(n)+ clusters, leading to the formation of (MAu(n)O2+) ad complexes with different equilibrium configurations. The highest adsorption energy was obtained when both atoms of O2 bind on top of the M impurity, and it is larger for Ti doped clusters than for Fe doped clusters, showing an odd-even effect trend with size n, which is opposite for Ti as compared to Fe complexes. For those adsorption configurations of (MAu(n)O2+) ad involving only Au sites, the adsorption energy is similar to or smaller than that for similar configurations of Au(n)+1O2 + complexes. However, the highest adsorption energy of (MAu(n)O2+) ad is higher than that for (Au(n)+1O2+) ad by a factor of approximately 4.0 (1.2) for M = Ti (M = Fe). The trends with size n are rationalized in terms of O-O and O-M bond distances, as well as charge transfer between oxygen and cluster substrates. The spin multiplicity of those (MAu(n)O2+) ad complexes with the highest O2 adsorption energy is a maximum (minimum) for M = Fe (Ti), corresponding to parallel (anti-parallel) spin coupling of MAu(n)+ clusters and O2 molecules. Finally, we obtained the minimum energy equilibrium structure of complexes (Au(n)O2+) dis and (MAu(n)O2+) dis containing two separated O atoms bonded at different sites of Au(n)+ and MAu(n)+ clusters, respectively. For (MAu(n)O2 (+)) dis, the equilibrium configuration with the highest adsorption energy is stable against separation in MAu(n)+ and O2 fragments, respectively. Instead, for (Au(n)O2+) dis, only the complex n = 6 is stable against separation in Au(n)+ and O2 fragments. The maximum separation energy of (MAu(n)O2+) dis is higher than the O2 adsorption energy of (MAu(n)O2+) ad complexes by factors of approximately 1.6 (2.5), 1.6 (1.7), 1.5 (2.4), 1.5 (1.3), and 1.6 (1.8) for M = Ti (Fe) complexes in the range n = 3-7, respectively. |
Outcomes in the Randomized CoreValve US Pivotal High Risk Trial in Patients With a Society of Thoracic Surgeons Risk Score of 7% or Less.
Transcatheter aortic valve replacement (TAVR) is now a well-accepted alternative to surgical AVR (SAVR) for patients with symptomatic aortic stenosis at increased operative risk. There is interest in whether TAVR would benefit patients at lower risk. The Society of Thoracic Surgeons Predicted Risk of Mortality (STS PROM) has trended downward in US TAVR trials and the STS/American College of Cardiology Transcatheter Valve Therapy Registry. We hypothesized that if the Society of Thoracic Surgeons Predicted Risk of Mortality (STS PROM) alone is sufficient to define decreased risk, the contribution to survival based on the degree of invasiveness of the TAVR procedure will decrease, making it more difficult to show improved survival and benefit over SAVR. The CoreValve US Pivotal High Risk Trial was a multicenter, randomized, noninferiority trial. This retrospective analysis evaluated patients who underwent an attempted implant and had an STS PROM of 7% or less. The trial was performed at 45 US sites. Patients had severe aortic stenosis and were at increased surgical risk based on their STS PROM score and other risk factors. Eligible patients were randomly assigned (1:1) to self-expanding TAVR or to SAVR. We retrospectively stratified patients by the overall median STS PROM score (7%) and analyzed clinical outcomes and quality of life using the Kansas City Cardiomyopathy Questionnaire in patients with an STS PROM score of 7% or less. The mean (SD) ages were 81.5 (7.6) years for the TAVR group and 81.2 years (6.6) for the SAVR group. A little more than half were men (57.9% in the TAVR group and 55.8% in the SAVR group). Of 750 patients who underwent attempted implantation, 383 (202 TAVR and 181 SAVR) had an STS PROM of 7% or less (median [interquartile range]: TAVR, 5.3% [4.3%-6.1%]; SAVR, 5.3% [4.1%-5.9%]). Two-year all-cause mortality for TAVR vs SAVR was 15.0% (95% CI, 8.9-10.0) vs 26.3% (95% CI, 19.7-33.0) (log rank P = .01). The 2-year rate of stroke for TAVR vs SAVR was 11.3% vs 15.1% (log rank P = .50). Quality of life by the Kansas City Cardiomyopathy Questionnaire summary score showed significant and equivalent increases in both groups at 2 years (mean [SD] TAVR, 20.0 [25.0]; SAVR, 18.6 [23.6]; P = .71; both P < .001 compared with baseline). Medical benefit, defined as alive with a Kansas City Cardiomyopathy Questionnaire summary score of at least 60 and a less than 10-point decrease from baseline, was similar between groups at 2 years (TAVR, 51.0%; SAVR, 44.4%; P = .28). Self-expanding TAVR compares favorably with SAVR in high-risk patients with STS PROM scores traditionally considered intermediate risk. Clinicaltrials.gov Identifier: NCT01240902. |
Comparison of two immunization schedules with recombinant hepatitis B vaccine and natural immunity acquired by hepatitis B infection in dialysis patients.
In a prospective study over a 2-year period we compared two practical dosage schedules to vaccinate dialysis patients against hepatitis B virus (HBV) infection using a yeast-derived recombinant hepatitis B vaccine (Engerix-B). In addition, the natural history of this acquired immunity was compared with that developed through HBV infection in dialysis patients and healthy subjects. Patients on dialysis treatment (haemo or peritoneal) who were tested to be negative for hepatitis B surface antigen (HBsAg), anti-HBs and anti-HB core were allocated at random to receive HB vaccine according to one of the two schedules. The two groups receiving the vaccine were matched for age, sex, mean duration on dialysis and the form of dialysis treatment received. The group of patients who received a four-dose schedule (at 0, 1, 2 and 6 months) of 40 micrograms of HB vaccine each time (group 2) achieved a seroconversion rate of 79% 1 month after the last dose (at month 7) compared with a seroconversion rate of 55% in those who received three doses (at 0, 1 and 6 months) of 40 micrograms each (group 1). Healthy controls who received half the amount of vaccine on a three-dose schedule (group 3) attained 100% seroconversion (p < 0.05). When retested at 24 months, 30% of seroconverters in group 1 had lost their protective immunity, compared with only 6% in group 2 and 15% in group 3. The magnitude of antibody response (total and anti-(a)-specific) was assessed in the vaccinees at 24 months and compared with that of two other control groups, dialysis patients (group 4) and healthy volunteers (group 5), who had acquired immunity from HBV infection. In general, the total and anti-(a)-specific HBs titres in the dialysis patients (groups 1, 2 and 4) were lower than in their corresponding healthy controls (groups 3 and 5), irrespective of whether the protective immunity was acquired by vaccination or HBV infection. However, the anti-HBs titres in dialysis patients who received four doses were significantly higher than in those who received only three doses (p < 0.05), which indicated a better protective immunity in favour of the former regime. The magnitude of antibody response in the vaccinees of groups 2 and 3 compared well with their respective controls, groups 4 and 5, who had acquired their immunity through HBV infection. This implied that the yeast-derived vaccine was sufficiently immunogenic and provided lasting protection in patients and healthy subjects vaccinated by an appropriate dosage schedule.(ABSTRACT TRUNCATED AT 400 WORDS) |
Pharmacokinetics and Tolerability of Rufinamide Following Single and Multiple Oral Doses and Effect of Food on Pharmacokinetics in Healthy Chinese Subjects.
Rufinamide is a triazole derivative that is structurally unrelated to currently marketed antiepileptic medications for add-on treatment of seizures in the setting of Lennox-Gastaut syndrome in patients from the age of 4 years. The purpose of this study was to determine the pharmacokinetic and safety profile of single and multiple doses of rufinamide in healthy Chinese subjects. The effects of food and gender on the pharmacokinetic properties of rufinamide were also evaluated. In the single-dose study, volunteers were randomly assigned to 4 dose groups and received a single dose of 200, 400, 800, 1200 mg rufinamide tablets under fasting condition. Ten subjects in the 200-mg dose group were randomly assigned to either a high-fat or non-high-fat breakfast group in each study period. The drug administration was separated by a washout period of 7 calendar days. In the multiple-dose study, 10 subjects were administered on an empty stomach rufinamide 200 mg twice daily for 6 consecutive days. Liquid chromatography tandem mass spectrometry (LC-MS/MS) method was applied to determine plasma concentration of rufinamide. Pharmacokinetic parameters, including the maximum plasma concentration (C max), the time to peak concentration (t max), the area under the plasma concentration versus time curve from time 0 to the last measurable concentration (AUC0-t ) and from time 0 to infinity (AUC0-∞), terminal elimination half-life (t 1/2), apparent volume of distribution (V d), apparent clearance (CL), average residence time (MRT), area under the plasma concentration versus time curve from time 0 to the last measurable concentration at steady state (AUCss), peak concentration (C max,ss) and trough level concentration (C min,ss) at steady state were calculated using non-compartmental models. Tolerability was assessed based on investigator inquiries, spontaneous reports and clinical evaluations. Rufinamide displayed a dose-dependent, but sub-proportional increase in exposure following single-dose and repeated dose administration. After administration of single dose of 200, 400, 800 and 1200 mg, without food, the rufinamide mean C max (standard deviation, SD) was 1806.5 (526.4), 2490 (564.8), 3719 (976.1) and 4166 (1187.1) μg/L, respectively. Mean AUC0-t (SD) was 34,571 (9484), 56,246 (18,077), 89,022 (23,379) and 107,316 (34,766) μg·h/L, respectively. While in fed condition at the dosage of 200 mg, mean C max (SD) and mean AUC0-t (SD) were 2363 (582) μg/L and 40,593 (10,516) μg·h/L, respectively. After administration of multiple doses, arithmetic mean (SD) values of C max and AUC0-t were 3566 (873) μg/L and 62,803 (19,873) μg·h/L, respectively. The steady state was achieved by day 3 of multiple dosing after 2 daily doses (twice a day), the corresponding accumulation factor (AUCss/AUC0-t) was 0.9057. Although there were no substantial effects on exposure resulting from gender differences, a notable food effect was observed, with AUC and C max increased by 17.4 and 30.8 %, respectively. Single- and multiple-dose phases were generally safe and well tolerated. Overall, 15 % (6/40) of subjects experienced a mild indisposition with no serious adverse events. On single and multiple dosing, rufinamide exhibited nonlinear pharmacokinetics and was well tolerated in healthy Chinese subjects. |
Clinical and cost efficacy of advanced wound care matrices for venous ulcers.
In the United States, venous leg ulcers (VLUs) are commonly associated with substantial disability, impaired quality of life, and high economic costs. Compression therapy, which has remained the standard care for VLUs over several decades, is often insufficient to heal VLUs in a timely manner. VLU-related treatment costs are directly related to time to achieve complete wound closure. Advanced wound care matrices (AWCMs) developed to stimulate wound healing may reduce VLU-related costs associated with delayed healing. Randomized controlled trials (RCTs) have evaluated the wound-healing efficacy of several AWCMs in patients with VLUs. However, comparisons of products' clinical and cost efficacy, which may guide clinical and formulary determinations, are lacking. To evaluate, in terms of number needed to treat (NNT), the comparative clinical and cost efficacy of targeted AWCMs as adjuncts to compression therapy for the treatment of chronic VLUs from the U.S. health care system (payer) perspective. A review of published articles (from the earliest available Medline publication date to June 1, 2011) identified RCTs evaluating complete wound closure rates for up to 24 weeks in patients with VLUs treated with targeted AWCMs (Apligraf, Oasis, or Talymed) plus compression therapy compared with compression therapy alone. The most favorable estimates of product efficacy (i.e., those that were statistically significant compared with compression therapy) were used. These included statistically adjusted results for Apligraf as reported in the product insert and the biweekly application for Talymed. Based on the reported efficacy of targeted AWCMs, we calculated the NNT to achieve 1 additional treatment success (i.e., complete wound closure) over that which was achieved with standard therapy alone; 95% CIs were estimated using the Wilson score method proposed by Newcombe. Cost efficacy, defined as the incremental cost per additional successfully treated patient, was then calculated by multiplying the NNT associated with each treatment by the product acquisition cost per treated VLU episode. One study for each of 3 targeted AWCMs (Apligraf [n=130 treatment, n=110 control]; Oasis Wound Matrix [n=62 treatment, n=58 control]; and Talymed [n=22 treatment, n=20 control]) met inclusion criteria. Study designs and wound characteristics varied. Average VLU sizes were 1 cm2, 10-12 cm2, and 10-13 cm2 in the studies of Apligraf, Oasis, and Talymed, respectively. Ulcer duration exceeded 12 months for 50% of patients in the Apligraf study and was at least 7 months for 47% of patients in the Oasis study; patients with ulcers exceeding 6 months were excluded from the study of Talymed. Length of follow-up was 24 weeks for Apligraf, 12 weeks for Oasis, and 20 weeks for Talymed. NNT point estimates of clinical efficacy were 2 for Talymed, 5 for Oasis, and 6 for Apligraf; 95% CIs ranged from 2 to 8 for Talymed, 3 to 24 for Apligraf, and 3 to 39 for Oasis. Incremental costs (95% CIs) per additional successfully treated patient were $1,600 ($1,600-$6,400) for Talymed, $3,150 ($1,890-$24,570) for Oasis, and $29,952 ($14,976-$119,808) for Apligraf. The most expensive AWCM for the treatment of VLUs did not appear to provide the greatest comparative clinical or cost efficacy. Conclusions must be tempered by the small number of available studies (n=3), variability in trial duration (from 12 to 24 weeks) and baseline wound characteristics, and limitations in study quality. Given the high prevalence, economic burden, and substantial disability of VLUs, and the wide variation in costs for AWCMs, payers need more high-quality head-to-head comparisons to guide coverage and reimbursement determinations for these products. |
Refined 1.83 A structure of trypanosomal triosephosphate isomerase crystallized in the presence of 2.4 M-ammonium sulphate. A comparison with the structure of the trypanosomal triosephosphate isomerase-glycerol-3-phosphate complex.
Triosephosphate isomerase (TIM) is a dimeric glycolytic enzyme. TIM from Trypanosoma brucei brucei has been crystallized at pH 7.0 in 2.4 M-ammonium sulphate. The well-diffracting crystals have one dimer per asymmetric unit. The structure has been refined at 1.83 A resolution with an R-factor of 18.3% for all data between 6 A and 1.83 A (37,568 reflections). The model consists of 3778 protein atoms and 297 solvent atoms. Subunit 1 is involved in considerably more crystal contacts than subunit 2. Correlated with these differences in crystal packing is the observation that only in the active site of subunit 2 is a sulphate ion bound. Furthermore, significant differences with respect to structure and flexibility are observed in three loops near the active site. In particular, there is a 7 A positional difference of the tip of the flexible loop (loop 6) when comparing subunit 1 and subunit 2. Also, the neighbouring loops (loop 5 and loop 7) have significantly different conformations and flexibility. In subunit 1, loop 6 is in an "open" conformation, in subunit 2, loop 6 is in an "almost closed" conformation. Only in the presence of a phosphate-containing ligand, such as glycerol-3-phosphate, does loop 6 take up the "closed" conformation. Loop 6 and loop 7 (and also to some extent loop 5) are rather flexible in the almost closed conformation, but well defined in the open and closed conformations. The closing of loop 6 (167 to 180), as observed in the almost closed conformation, slightly changes the main-chain conformation of the catalytic glutamate, Glu167, leading to a change of the chi 1 angle of this residue from approximately -60 degrees to approximately 60 degrees and the weakening of the hydrogen bonds between its polar side-chain atoms and Ser96. In the closed conformation, in the presence of glycerol-3-phosphate, the main-chain atoms of Glu167 remain in the same position as in the almost closed conformation, but the side-chain has rotated around the CA-CB bond changing chi 1 from approximately 60 degrees to approximately -60 degrees. In this new position the hydrogen bonding to Ser96 is completely lost and also a water-mediated salt bridge between OE2(Glu167) and NE(Arg99) is lost. Comparison of the two independently refined subunits, showed that the root-mean-square deviation for all 249 CA atoms is 0.9 A; for the CA atoms of the beta-strands this is only 0.2 A. The average B-factor for all subunit 1 and subunit 2 atoms is 20 A2 and 25 A2, respectively.(ABSTRACT TRUNCATED AT 400 WORDS) |
Design of a ruthenium-cytochrome c derivative to measure electron transfer to the radical cation and oxyferryl heme in cytochrome c peroxidase.
A new ruthenium-labeled cytochrome c derivative was designed to measure the actual rate of electron transfer to the Trp-191 radical cation and the oxyferryl heme in cytochrome c peroxidase compound I {CMPI(FeIV = O,R.+)}. The H39C,C102T variant of yeast iso-1-cytochrome c was labeled at the single cysteine residue with a tris (bipyridyl)ruthenium(II) reagent to form Ru-39-Cc. This derivative has the same reactivity with CMPI as native yCc measured by stopped-flow spectroscopy, indicating that the ruthenium group does not interfere with the interaction between the two proteins. Laser excitation of the 1:1 Ru-39-Cc-CMPI complex in low ionic strength buffer (2 mM phosphate, pH 7) resulted in electron transfer from RuII* to heme c FeIII with a rate constant of 5 x 10(5) s-1, followed by electron transfer from heme c Fe II to the Trp-191 indolyl radical cation in CMPI(FeIV = O,R*+) with a rate constant of k(eta) = 2 x 10(6) s-1. A subsequent laser flash led to electron transfer from heme c to the oxyferryl heme in CMPII-(FeIV = O,R) with a rate constant of k(etb) = 5000 s-1. The location of the binding domain was determined using a series of surface charge mutants of CcP. The mutations D34N, E290N, and A193F each decreased the values of k(eta) and k(etb) by 2-4-fold, consistent with the use of the binding domain identified in the crystal structure of the yCc-CcP complex for reduction of both redox centers [Pelletier, H., & Kraut, J. (1992) Science 258, 1748-1755]. A mechanism is proposed for reduction of the oxyferryl heme in which internal electron transfer in CMPII(FeIV = O,R) leads to the regeneration of the radical cation in CMPII-(FeIII,R*+), which is then reduced by yCcII. Thus, both steps in the complete reduction of CMPI involve electron transfer from yCcII to the Trp-191 radical cation using the same binding site and pathway. Comparison of the rate constant k(eta) with theoretical predictions indicate that the electron transfer pathway identified in the crystalline yCc-CcP complex is very efficient. Stopped-flow studies indicate that native yCcII initially reduces the Trp-191 radical cation in CMPI with a second-order rate constant ka, which increases from 1.8 x 10(8) M-1 s-1 at 310 mM ionic strength to > 3 x 10(9) M-1 s-1 at ionic strengths below 100 mM. A second molecule of yCcII then reduces the oxyferryl heme in CMPII with a second-order rate constant kb which increases from 2.7 x 10(7) M-1 s-1 at 310 mM ionic strength to 2.5 x 10(8) M-1 s-1 at 160 mM ionic strength. As the ionic strength is decreased below 100 mM the rate constant for reduction of the oxyferryl heme becomes progressively slower as the reaction is limited by release of the product yCcIII from the yCcIII-CMPII complex. Both ruthenium photoreduction studies and stopped-flow studies demonstrate that the Trp-191 radical cation is the initial site of reduction in CMPI under all conditions of ionic strength. |
Radical ions with nearly degenerate ground state: correlation between the rate of spin-lattice relaxation and the structure of adiabatic potential energy surface.
Paramagnetic spin-lattice relaxation (SLR) in radical cations (RCs) of the cycloalkane series in liquid solution was studied and analyzed from the point of view of the correlation between the relaxation rate and the structure of the adiabatic potential energy surface (PES) of the RCs. SLR rates in the RCs formed in x-ray irradiated n-hexane solutions of the cycloalkanes studied were measured with the method of time-resolved magnetic field effect in the recombination fluorescence of spin-correlated radical ion pairs. Temperature and, for some cycloalkanes, magnetic field dependences of the relaxation rate were determined. It was found that the conventional Redfield theory of the paramagnetic relaxation as applied to the results on cyclohexane RC, gave a value of about 0.2 ps for the correlation time of the perturbation together with an unrealistically high value of 0.1 T in field units for the matrix element of the relaxation transition. The PES structure was obtained with the DFT quantum-chemical calculations. It was found that for all of the cycloalkanes RCs considered, including low symmetric alkyl-substituted ones, the adiabatic PESes were surfaces of pseudorotation due to avoided crossing. In the RCs studied, a correlation between the SLR rate and the calculated barrier height to the pseudorotation was revealed. For RCs with a higher relaxation rate, the apparent activation energies for the SLR were similar to the calculated heights of the barrier. To rationalize the data obtained it was assumed that the vibronic states degeneracy, which is specific for Jahn-Teller active cyclohexane RC, was approximately kept in the RCs of substituted cycloalkanes for the vibronic states with the energies above and close to the barrier height to the pseudorotation. It was proposed that the effective spin-lattice relaxation in a radical with nearly degenerate low-lying vibronic states originated from stochastic crossings of the vibronic levels that occur due to fluctuations of the interaction between the radical and the solvent. The magnitude of these fluctuations, ~100 cm(-1), determines the upper scale of the unperturbed splitting between the vibronic states, for which the manifestation of this paramagnetic relaxation mechanism could be expected. Our estimate for the relaxation rate derived using standard Landau-Zener model of nonadiabatic transitions at the level crossing agrees with the experimental data. This paramagnetic relaxation mechanism can also be operative in paramagnetic species of other types such as linear radicals, radicals with threefold degeneracy, paramagnetic centers in crystals, etc. It looks likely that the proposed SLR mechanism can be quenched by a fast vibrational relaxation in radicals. |
Strontium- and cobalt-substituted bioactive glasses seeded with human umbilical cord perivascular cells to promote bone regeneration via enhanced osteogenic and angiogenic activities.
Designing and developing new biomaterials to accelerate bone healing are currently under progress. In this study, we attempted to promote osteogenesis using strontium- and cobalt-substituted bioactive glasses (BGs) seeded with human umbilical cord perivascular cells (HUCPVCs) in a critical size defect in the distal femur of rabbit animal model. The BG particles were successfully synthesized in the form of granules using the melt-derived route. After being isolated, HUCPVCs were expanded and then characterized to use during in vitro and in vivo procedures. The in vitro effects of the synthesized glasses on the isolated HUCPVCs as well as on cell lines SaOS-2 (selected for screening the osteogenetic potential) and HUVEC (selected for screening the angiogenic potential) were assessed by analyzing cytotoxicity, cell attachment, bone-like nodule formation, and real time PCR. The results of in vitro tests indicated cytocompatibility of the synthesized BG particles. For in vivo study, the HUCPVCs-seeded BGs were implanted into the animal's body. Radiographic imaging, histology and immunohistology staining were performed on the harvested specimens at 4 and 12weeks post-surgery. The in vivo evaluation of the samples showed that all the cell/glass constructs accelerated bone healing process in comparison with blank controls. The best in vitro and in vivo results were associated to the BGs containing both strontium and cobalt ions. This group of bioactive glasses is able to promote both osteogenesis and angiogenesis and can therefore be highly suitable for the development of advanced functional bone substitutes. Bone regeneration is considered as an unmet clinical need. The most recent researches focused on incorporation of strontium (Sr2+) and cobalt (Co2+) ions into bioactive glasses structure. Strontium is an alkaline earth metal which is currently used in the treatment of osteoporosis. Also, cobalt is considered as another promising element in the bone regeneration field that may induce hypoxia-mediated angiogenesis. In this study, the osteogenic potential of the strontium- and cobalt-substituted bioactive glasses in granule form seeded with human umbilical cord perivascular cells (HUCPVCs) was evaluated in vitro and in vivo. Indeed, the main goal of this study was to improve the osteogenenic and angiogenic properties of bioactive glasses through the incorporation of strontium and cobalt ions in the glass composition. Although some researches have been conducted on this subject, the influence of the simultaneous use of strontium and cobalt ions on the improvement of bone healing in vivo has been not yet well understood and, therefore, deserves further investigation. |
Problems associated with substandard and counterfeit drugs in developing countries: a review article on global implications of counterfeit drugs in the era of antiretroviral (ARVs) drugs in a free market economy.
To review the global implications associated with the use of substandard and or counterfeit drugs in developing and may be developed countries. The focus of this review is particularly on antiretroviral (ARVs), antimalarials and other drugs. Review of various literatures through Pub-Med, Medline, Google and Internet search to retrieve and download published materials was done by the author of this review paper. When patients receive a counterfeit medicines, they are subjected to multiple risks. They often suffer more than just an inconvenience; as they become victims of fraud medicines and are all put at risk of adverse effects from unprescribed medicines or substandard ingredients. Additionally, patients may lose confidence in health care professionals including their physician and pharmacist, and potentially modern medicine or the pharmaceutical industry in general. Counterfeit or substandard (poor quality) drugs pose threats to society; not only to the individual in terms of the health side effects experienced, but also to the public in terms of trade relations, economic implications, and the effects on global pandemics. It is vital for suppliers, providers, and patients to be aware of current trends in counterfeiting in order to best prepare for encounters with suspicious products. Furthermore, this is an issue that needs to be continually dealt with on national and international policy levels. Developing countries should try their level best to establish good laboratories for monitoring and checking quality of all pharmaceuticals manufactured locally and those imported or donated to these countries. The Ministries of Health and all stakeholders involved in this issue must ensure that all drugs meet the set or established international standards and national standards. Failure to do so will be to misuse the hard earned forex that is normally borrowed from banks for the procurement and distribution of drugs to its people. Indeed sub-standard medications do more harm than good to people's health and it is unethical to give such drugs to people. Of course, in any market, some corruption and fraud always exist, but there are few commercial markets where fraud can have such drastic impact on global health and welfare. It is essential, therefore, that a multi-faceted approach be used to control this problem which affects the international community and continuously threatens the health of millions of people especially in developing countries. Developing countries should try their best at all costs establish good laboratories for monitoring or checking for quality control for all pharmaceuticals locally manufactured and those imported (entering) or donated to countries to make sure that they meet the set or established international or national standards. Short of that countries will be wasting a lot of money using forex which has been borrowed in a form a loans procuring and distributing to its people sub-standard medications which will do more harm than good to its indigenous people and this is unethical per se to give people drugs not meeting required set international standards. |
Selection originating from protein stability/foldability: Relationships between protein folding free energy, sequence ensemble, and fitness.
Assuming that mutation and fixation processes are reversible Markov processes, we prove that the equilibrium ensemble of sequences obeys a Boltzmann distribution with exp(4Nem(1-1/(2N))), where m is Malthusian fitness and Ne and N are effective and actual population sizes. On the other hand, the probability distribution of sequences with maximum entropy that satisfies a given amino acid composition at each site and a given pairwise amino acid frequency at each site pair is a Boltzmann distribution with exp(-ψN), where the evolutionary statistical energy ψN is represented as the sum of one body (h) (compositional) and pairwise (J) (covariational) interactions over all sites and site pairs. A protein folding theory based on the random energy model (REM) indicates that the equilibrium ensemble of natural protein sequences is well represented by a canonical ensemble characterized by exp(-ΔGND/kBTs) or by exp(-GN/kBTs) if an amino acid composition is kept constant, where ΔGND≡GN-GD,GN and GD are the native and denatured free energies, and Ts is the effective temperature representing the strength of selection pressure. Thus, 4Nem(1-1/(2N)),-ΔψND(≡-ψN+ψD), and -ΔGND/kBTs must be equivalent to each other. With h and J estimated by the DCA program, the changes (ΔψN) of ψN due to single nucleotide nonsynonymous substitutions are analyzed. The results indicate that the standard deviation of ΔGN(=kBTsΔψN) is approximately constant irrespective of protein families, and therefore can be used to estimate the relative value of Ts. Glass transition temperature Tg and ΔGND are estimated from estimated Ts and experimental melting temperature (Tm) for 14 protein domains. The estimates of ΔGND agree with their experimental values for 5 proteins, and those of Ts and Tg are all within a reasonable range. In addition, approximating the probability density function (PDF) of ΔψN by a log-normal distribution, PDFs of ΔψN and Ka/Ks, which is the ratio of nonsynonymous to synonymous substitution rate per site, in all and in fixed mutants are estimated. The equilibrium values of ψN, at which the average of Δψ in fixed mutants is equal to zero, well match ψN averaged over homologous sequences, confirming that the present methods for a fixation process of mutations and for the equilibrium ensemble of ψN give a consistent result with each other. The PDFs of Ka/Ks at equilibrium confirm that Ts negatively correlates with the amino acid substitution rate (the mean of Ka/Ks) of protein. Interestingly, stabilizing mutations are significantly fixed by positive selection, and balance with destabilizing mutations fixed by random drift, although most of them are removed from population. Supporting the nearly neutral theory, neutral selection is not significant even in fixed mutants. |
In vivo documentation of shape and position changes of MRI-visible mesh placed in rectovaginal septum.
Large deformations in synthetic meshes used in pelvic organ prolapse surgery may lead to suboptimal support for the underlying tissue, graft-related complications as well as recurrence. Our aim was to quantify in vivo longitudinal changes in mesh shape and geometry in a large animal model. We compare two commonly used mesh shapes, armed and flat, that are differently affixed. The secondary outcomes were active and passive biomechanical properties. A total of 18 animals were used. Six each were implanted with either an arm mesh, a flat mesh or underwent a sham surgery. PVDF meshes loaded with Fe2O3 were used to facilitate their visualization in vivo. MR images were taken at 2, 14 and 60 days after implantation and 3D models of the meshes were created at each time point. We calculate the Effective Surface Area (ESA), i.e. the support that the mesh provides to the underlying tissue using custom developed techniques. Longitudinal changes in the mesh shape were studied by comparing the respective 3D models using part comparison analyses. The root means square difference (RMSD) and the modified Hausdorff distance (MHD) were calculated to obtain an objective value for the part comparisons. Wall thickness maps were produced on 3D models. Mesh arm length and their ellipticity profiles were also evaluated. Active and passive biomechanical tests on vaginal tissue overlaying the mesh were conducted using a contractility assay and a uniaxial loading protocol. MR images of 5 animals in each group were used for longitudinal comparison. Compared to the initial implant size, there was an immediate drop in the ESA measurement at day 2 of almost 32.22 [7.06] % (median [IQR]) for flat meshes, and by 17.59 [6.50] % for arm meshes. After 14 days, the reduction in area was 41.84 [14.89] % and 27.18 [20.44] %, and at day 60 it was 36.61 [6.64] % and 26.43 [14.56] % for the flat and armed meshes respectively. The reduction in area in the two groups was different between the two groups only day 14 (p = 0.046). The ellipticity of the arms was 0.81 [0.08] (median [IQR]) and there was no significant change in the ellipticity profiles over time. The mesh arm length did not change significantly over time. The part comparison showed a maximum difference of 4.26 [3.29] mm in 3D models according to the MHD measure, which is clinically not relevant. Comparison of high thickness areas on the thickness maps correlated well with the areas of mesh folding in the arm mesh group observed during postmortem dissection. Thickness maps did not help us understand why the flat meshes had a reduction in support area. The comfort zone stiffness of the flat mesh and of the central part of the arm mesh were 2.4 fold and 4.5 times stiffer compared to sham groups, respectively. The arms were 36% stiffer than the central part of the mesh. The comfort zone length of the sham group was 46% longer than the flat mesh group (p = 0.027) and 59% longer than that of the central part of the arm mesh (p = 0.005). There was no significant difference in vaginal contractile forces generated in samples from the arm, flat mesh, and sham groups. This is a first longitudinal study observing deformations in vaginally implanted synthetic meshes in a large animal model. A novel methodology is presented to calculate the area of the vaginal tissue effectively supported by the mesh implant. Immediately post-operatively, a reduction in 32% and 17% was noted, which remained stable over the 60 following days of observation. We use thickness maps to analyze the cause of this dramatic immediate reduction. In the armed mesh we found it to be mesh folding at the interface between the arms and central part. For the flat mesh we suggest that pore aggregation during suturing. |
Alteration in interactions between tumor-infiltrating lymphocytes and tumor cells in human melanomas after chemotherapy or immunotherapy.
Alteration in interactions between tumor-infiltrating lymphocytes (TILs) and tumor cells after chemotherapy or immunotherapy was studied in metastatic melanoma patients. Tumors were harvested from surgical specimens 17 days after the end of chemotherapy with cisplatin, vinblastine, and dacarbazine (CVD). Tumors of nonlymph-node metastases from two responders yielded neither TILs nor tumor cells, whereas those from all four nonresponders had both TILs [(1.1-13.8) x 10(6) cells/g tumor] and tumor cells [(2.8-30.8) x 10(6) cells/g tumor). Tumors of lymph node metastases from nine patients yielded substantial numbers both of TILs and tumor cells, regardless of different clinical responses, except with one complete responder, whose tumor did not contain tumor cells. The mean increase of TILs from these tumors (n = 14) 3-4 weeks after incubation with 200 U/ml recombinant interleukin-2 (rIL-2) was 2.5-fold, whereas there was a 56-fold increase in TILs from untreated tumors (n = 3). CD3+ T cells predominated in TILs before and after expansion with IL-2. IL-2-activated TILs from five of six tumors tested displayed higher cytotoxicity against autologous tumor cells than against cells from any of three allogeneic tumors. Mean tumor cell numbers (10(6) cells/trial) obtained by serial needle biopsies for the same tumor in five patients decreased from 1.2 before therapy to 0.25 at day 4 of therapy (interferon alpha alone), and to 0.02 at day 8 (interferon alpha and IL-2). This decrease did not correlate with clinical responses. Yields (x 10(6) cells/g tumor) of TILs and tumor cells in subcutaneous melanomas obtained by excisional biopsies in one nonresponder under IL-2 therapy were respectively 0.2 and 1.1 before therapy (day 0), 0.1 and less than 0.01 during (day 7), 0.2 and less than 0.01 at the end of therapy (day 21), and 0.5 and 0.5 at the time of tumor progression (day 66). Yields of TILs and tumor cells in the other nonresponder were respectively 3 and 26 before (day 0), 16 and 3 during (day 7), and 0.4 and less than 0.01 at the end of IL-2 therapy (day 17), and 2.5 and 6 at the time of progression (day 62). TILs in these two patients before therapy proliferated well in culture with IL-2 (570- and 720-fold, respectively), and showed higher cytotoxicity against autologous tumor cells, whereas none of those from the five tumors biopsied during or at the end of IL-2 therapy proliferated. TILs at the time of progression showed modest proliferation (54- and 76-fold, respectively) and showed major-histocompatibility-complex-nonrestricted cytotoxicity. In summary, a decrease in the number of live tumor cells did not always correlate with clinical response in either therapy. CVD chemotherapy may simply impair IL-2-induced proliferation of TILs. IL-2 therapy may induce transient unresponsiveness of TILs to IL-2. |
Comparison of percutaneous balloon dilation kyphoplasty and percutaneous vertebroplasty in treatment for thoracolumbar vertebral compression fractures.
Osteoporotic vertebral compression fractures (OVCFs) are common diseases in elderly patients and can cause serious thoracolumbar compression fractures. For patients with such fractures, conservative treatment, nail-stick fixation, percutaneous vertebroplasty (PVP) and percutaneous kyphoplasty (PKP) can be selected as treatment methods. In this study, we aimed to compare the clinical efficacy of PKP and PVP in the treatment of osteoporotic thoracolumbar vertebral compression fractures. One hundred and sixty-one patients with single-stage osteoporotic vertebral compression fracture in thoracolumbar were enrolled and divided into two groups, percutaneous balloon kyphoplasty (PKP group) and percutaneous vertebroplasty (PVP group). The subjects were selected from patients who were once treated in our hospital from January 2012 to December 2015. There were 91 cases in PKP group and 70 cases in PVP group. The hospitalization time, operation-related index (including blood loss, bone cement injection, surgical time and number of intraoperative fluoroscopy), bedrest time, visual analog pain score (VAS), Cobb's angle, vertebral anterior height, Oswestry Disability Index (ODI) dysfunction index and quality of life score were compared to evaluate the clinical effects of the two treatment methods. There were significant differences in hospitalization time, operation-related index (including blood loss, bone cement injection, operation time, number of intraoperative fluoroscopies) and bed rest time between the two groups. Compared with the patients in PVP group, patients of PKP group had less hospital stay (p<0.001), less time in bed (p<0.05) and less intraoperative blood loss (p<0.05). In addition, the number of times we used intraoperative fluoroscopy was significantly different between the two groups (p<0.001). However, the operation time of PKP group was longer than that of PVP group, and the amount of intraoperative cement injection was more than that of PVP group (p<0.05). After treatment, VAS scores in both groups were dramatically decreased, of which the scores in PKP group were markedly lower than that in PVP group and the difference was statistically significant (p<0.05). The changes of Cobb's angle, the height of anterior vertebral body and ODI scores in PKP group were noticeably better than PVP group (p<0.05). There were 5 cases occurring intraoperative cement leakage in PKP group and 12 cases in PVP group, indicating that the former is relatively better (p<0.001). However, no significant difference was found between the two groups in the occurrence of secondary vertebral fractures at 1 month, 3 months, 6 months and 12 months after treatment (p>0.05). The clinical effects of both PKP and PVP in the treatment of osteoporotic vertebral compression fractures are good, of which the reductive and analgesic effect of PKP is superior to that of PVP and the former has less leakage of cement, higher safety and fewer complications. |
Differential effects of various oil diets on the risk of cardiac arrhythmias in rats.
Independently of the problem of atherogenesis, the amount and type of fat intake influences the risk of cardiac arrhythmias. However, the relative effectiveness of different fats and the underlying mechanisms are controversial. The aim of the present study was to compare the effects of various oil-enriched diets on the risk of ventricular arrhythmias in rat hearts under conditions of ischaemia and reperfusion and to help clarify the mechanisms underlying the differing effects of the oils on the occurrence of arrhythmias. Over a 10-week period, we studied five groups of young male Wistar rats given a low-fat chow diet or one enriched with 10% hydrogenated coconut oil, corn oil, linseed oil or sardine oil. Electrocardiograms were recorded from the isolated hearts (Langendorff preparation) perfused with a modified Krebs-Henseleit solution. Ischaemia was induced by a 20 min occlusion of the left anterior descending coronary artery. In another series of experiments, a 10 min occlusion was followed by a 20 min reperfusion period. The times between the first occurrence of extrasystole and the incidence of ventricular tachycardia and fibrillation were determined. The size of the ischaemic zone was assessed using malachite green. The fatty acid composition of the myocardial tissue was analysed using gas chromatography. An increase in the risk of ventricular arrhythmias under conditions of both ischaemia and reperfusion was obvious in the rats that consumed large quantities of saturated fatty acids (coconut oil) and in the group with a very low intake of fat. Polyunsaturated fatty acids (PUFAs), particularly fish oil, exerted a protective effect. The incidence of ventricular fibrillation was 75% in the low-fat group, 67% in the coconut-oil group, 44% in the corn-oil group, 40% in the linseed-oil group and 10% in the fish-oil group. The time until the first occurrence of extrasystole, the incidence of ventricular tachycardia and the incidence of reperfusion-induced ventricular fibrillation were influenced in a similar manner. The size of the ischaemic zone was significantly reduced in the groups given diets enriched with PUFAs. All protective effects were abolished, however, by cyclooxygenase inhibition with aspirin. The fatty acid composition of myocardial tissue, the ratio of n-3 to n-6 fatty acids and the double-bond index were significantly affected by the various diets. Whereas saturated fatty acids are obviously proarrhythmic, diets enriched with n-6 or n-3 PUFAs both exert antiarrhythmic effects. Although n-3 fatty acids seem to be more effective, cardioprotection cannot simply be related to the replacement of n-6 by n-3 fatty acids in cardiac membrane phospholipids, given the beneficial effects of corn oil. In any case, replacement of n-3 by n-6 fatty acids is not the underlying mechanism. The overall reduction of prostaglandin formation cannot be the primary mechanism because the beneficial effects of diets rich in PUFAs were abolished by cyclooxygenase inhibition. We conlcude that, besides prostacyclin (PGI2 or PGI3), membrane fluidity and accompanying alterations in functional membrane proteins (e.g. protection from calcium overload) are key factors apart from vascular effects that influence the size of the ischaemic zone. |
Non-Hodgkin lymphoma in children: a 20-year population-based epidemiologic study in western Sweden.
The aim of this study was to investigate incidence, clinicopathologic features, prognostic risk factors, and long-term survival in non-Hodgkin lymphoma (NHL) in a 20-year population-based study of children using Swedish health care organizations and their central registry for childhood malignancies. The hospital registry, the Cause of Death Registry, and the two established Swedish registries for malignancy (the Swedish Cancer Registry and the National Registry for Solid Tumours in Childhood) were searched for children in western Sweden with NHL diagnosed from 1975 to 1994. The clinical files of all children with NHL were collected and abstracted for information regarding age at diagnosis, gender, disease characteristics, treatment, and outcome of treatment. All sections from paraffin-embedded blocks of tumors with a diagnosis of malignant lymphoma were collected and reexamined histopathologically and immunohistochemically. To guarantee that no patients with NHL were misdiagnosed, a reexamination of other childhood malignancies collected from these registries was also performed. Median follow-up duration of surviving patients is 10 years. The annual incidence of NHL in children younger than 15 years of age was 9/million children, representing 6% of all childhood malignancies during the investigation time. The male-female ratio was 4.1:1.0. Immunologic marker studies were available for 64 of the 77 NHLs: 41 patients had B-cell, 17 had T-cell, and 6 had Ki-1-positive anaplastic large cell lymphoma (ALCL). Two patients with Ki-1-positive ALCL were originally thought to have malignant histiocytosis and Langerhans cell histiocytosis (LCH), respectively. Treatment was the most significant prognostic factor; event-free survival (EFS) was 19% in the preprotocol era (1975 to 1979) and 74% from 1980 to 1994. Other than treatment, stage was the most significant prognostic factor; EFS was 86% for patients (1980 to 1994) with stage I or II disease and 64% for patients with stage III or IV disease, with a dismal prognosis for children with initial involvement of the bone marrow or central nervous system (EFS was 38% and 20%, respectively). Bulky disease and performance state at diagnosis were independent prognostic factors. The patterns of relapse, including early recurrence of the B-cell lymphomas, are in accordance with previous experience. The incidence of NHL was found to be somewhat higher than reported in our previous Nordic study. The higher incidence found in this study might be the result of the thorough data collection (based on hospital registry and cross-checked with all registries for malignant diseases in Sweden) or because reexamination of the tissue material was performed. A more pronounced male predominance than found in previous investigations was observed. The immunophenotypic distribution and the stage distribution is in accordance with earlier investigations. Treatment was the most important factor affecting outcome. A dramatic improvement of survival was seen with the introduction of intensive therapy; treatment success can be expected in 86% of children with localized disease and 64% of children with extensive disease. The absence of improvement in survival despite further treatment stratification with the introduction of the BFM protocol for B-cell-NHL is surprising. LSA2L2-like protocols seem to be as effective. Future studies on treatment of NHL must also concentrate on reducing the intensity of therapy in patients with lower risk disease to minimize late toxic effects. |
Treatment of primary graft dysfunction after lung transplantation with orally inhaled AP301: A prospective, randomized pilot study.
Primary graft dysfunction (PGD) after lung transplantation (LTx) carries significant morbidity and mortality in the early post-operative period and is associated with the development of chronic lung allograft dysfunction. AP301, an activator of epithelial sodium channel-mediated Na+ uptake represents a new concept for prevention and treatment of pulmonary edema and has shown promising results in the pre-clinical setting. This pilot study investigated the clinical effect of inhaled AP301 on patients with development of PGD > 1 according to International Society of Heart and Lung Transplantation criteria after primary LTx in a high-volume center and was conducted as a randomized, placebo-controlled, single-center pilot-study including 20 patients. All consecutive patients fulfilling inclusion criteria were screened for PGD at arrival on the intensive care unit (ICU) after LTx. After randomization, inhaled AP301 or placebo was administered by nebulizer twice daily for 7 days or until extubation. Otherwise, patients were treated according to routine clinical protocol. Partial pressure of arterial oxygen (Pao2)/fraction of inspired oxygen (Fio2) values were obtained until extubation and assessed as a primary outcome parameter. Patients were monitored for 30 days within the study protocol. From July 2013 to August 2014, 20 patients were randomized 1:1 to AP301 (Group 1) or placebo (Group 2). Both groups were comparable with regard to sex (40% women/60% men vs 50% women/50% men), mean age (55 ± 13 vs 54 ± 6 years), comorbidities, and diagnosis leading to LTx. The Pao2/Fio2 ratio at the time of inclusion was comparable in both groups, with a mean 235.65 ± 90.78 vs 214.2 ± 95.84 (p = 0.405), and there was no significant difference in the extravascular lung water index (13.88 ± 5.28 vs 16 ± 6.29 ml/kg, p = 0.476). The primary end point was mean Pao2/Fio2 ratio values between baseline and Day 3. In the AP301 group, only 1 patient was ventilated at Day 4 and no patients were ventilated after Day 4. In the placebo group, 5 patients were ventilated on Day 4 and 2 patients on Days 5, 6, and 7. The mean increase in the Pao2/Fio2 ratio was significantly higher in Group 1 patients, and the mean between baseline and at 72 hours was 365.6 ± 90.4 in Group 1 vs 335.2 ± 42.3 in Group 2 (p = 0.049). The duration of intubation was shorter in Group 1 than in Group 2 patients (2 ± 0.82 vs 3.7 ± 1.95 days; p = 0.02). ICU stay was 7.5 ± 3.13 days in Group 1 vs 10.8 ± 8.65 days in group 2 (p = 0.57). Survival at 30 days was 100%. No severe adverse events were recorded. This study was designed as a proof-of-concept pilot study. Although it was not powered to achieve statistical significances, the study demonstrated relevant clinical effects of inhaled AP301 on patients with PGD after primary LTx. The improved gas exchange led to a significantly shorter duration of mechanical ventilation and a trend towards a shorter ICU stay. Further investigation of AP301 for treatment of PGD in larger studies is warranted. The trial is registered at https://www.clinicaltrialsregister.eu/ctr-search/trial/2013-000716-21/AT. |
Algorithm for safe and effective reoperative thyroid bed surgery for recurrent/persistent papillary thyroid carcinoma.
The aim of this study was to review our experience with reoperative thyroid bed surgery (RTBS) for recurrent/persistent papillary thyroid cancer (PTC), and present an algorithm for safe and effective RTBS. This is a retrospective study. Records of 33 consecutive patients who underwent RTBS for recurrent/persistent PTC in a previously operated thyroid bed, and were operated upon by the senior author (R.P.T.) July 2001 to January 2006 were reviewed. Reports of the pre- and post-RTBS serum thyroglobulin (TG) levels, the high-resolution thyroid bed ultrasound examination, pre-RTBS FNA cytopathology, as well as the post-RTBS final histopathology were reviewed. Recurrent laryngeal nerve (RLN) monitoring was used for all patients. Reports of the intra-RTBS condition of the RLN and any reported surgical complications were reviewed. In addition, reports of the pre- and post-RTBS fiberoptic laryngoscopy as well as pre- and post-RTBS serum calcium levels were reviewed. In our study, 33 consecutive patients underwent RTBS for recurrent/persistent PTC with or without lateral neck dissection. In 30 patients, recurrent/persistent PTC was suspected because of rising serum TG levels, interpreted in conjunction with serum anti-TG-antibody titers by the endocrinology service at our institution. Three patients had serum anti-TG antibodies and their disease was detected and FNA confirmed by a regularly scheduled surveillance ultrasound examination. All patients underwent pre-RTBS high-resolution thyroid bed ultrasound examination and FNA for all suspicious masses. All patients had FNA-confirmed PTC in the thyroid bed. All patients had detailed diagrams localizing areas of FNA-confirmed PTC in the thyroid bed provided to the surgeon. In all study patients, post-RTBS histopathologic findings confirmed sites of recurrent/persistent PTC determined by pre-RTBS US guided FNA. All RLNs (53/53) that were at risk were successfully identified. In 3 patients, the RLN was electively resected because of the envelopment by a large paratracheal mass or tumor densely adherent to the RLN insertion point at the cricothyroid region. There was no incidence of unexpected RLN injury, permanent hypocalcemia, or any other surgery-related complication. Post-RTBS serum TG levels were significantly decreased or undetectable in most patients (2 patients had concurrent lung metastases), when compared with pre-RTBS levels. No patient exhibited thyroid bed recurrent/persistent PTC in the post-RTBS period based on semiannual high resolution neck ultrasound examination with a median follow-up of 2 years. Safe and effective RTBS is based on a multidisciplinary approach that enables the identification and localization of recurrent/persistent PTC. The surgical algorithm for RTBS described, provides a pathway that all endocrine-head and neck surgeons can comfortably utilize to treat this complex and challenging patient population. |
Feasibility and outcomes of paid undergraduate student nurse positions.
An Undergraduate Nurse Employment Demonstration Project (UNDP) was implemented in four Health Service Areas in British Columbia with a concurrent evaluation study. This demonstration project comprised the development and implementation of a new position in the BC healthcare system. The position enabled third- and fourth-year nursing students to be employed at their level of education. The purposes of the evaluation were to explore the feasibility and outcomes of this type of paid undergraduate student nurse employment. The three-year project and evaluation included both implementation and outcome analysis. The implementation evaluation design was descriptive and prospective, involving multiple data sources. The outcome evaluation design was quasi-experimental, with intervention and comparison groups. Learning outcomes for undergraduate nurses were increased confidence, organizational ability, competency and ability to work with a team. Workplace outcomes were increased unit morale, help with workload and improved patient care. New graduates with undergraduate nurse experience reported less time required for orientation and transition than other graduates who did not have this experience, and workplace nurses viewed these new graduates as more job-ready than other new graduates. After 21 months, new graduates with undergraduate nurse experience were less likely to move to other employment than other new graduates. Results from the four Health Service Areas indicated that the paid undergraduate nurse position was feasible and that outcomes benefited students, new graduates and workplaces. The undergraduate nurse position is now being implemented throughout all Health Service Areas in British Columbia.By 2000, concerns in British Columbia about the nursing workforce, workplace and patient safety had escalated to the point where diverse stakeholder groups were prepared to work together in new ways to prepare nursing graduates to be more job-ready, to recruit and retain new graduates and to retain existing nurses. Stakeholder groups were administrators, labour organizations, professional associations, educators and government. One idea to support job readiness and retention focussed on the feasibility of implementing cooperative education for nursing students. The effort was unsuccessful owing to lack of funding, but resulted in a review of the literature on cooperative education and other work-study programs. Cooperative education connects classroom learning with paid work experience for the purpose of enhancing students' education (Fitt and Heverly 1990; Heinemann and De Falco 1992; Ryder 1987). Reported benefits for students were improved job preparation and graduate retention (Ishida et al. 1998), additional staffing and reduction in orientation time (Cusack 1990; Ishida et al. 1998), increased practice judgment (Cusack 1990; Siedenberg 1989) and better workload management (Ross and Marriner 1985). A work-study model reported in the literature offered benefits similar to those of cooperative education, with greater flexibility in design. An example was the University of Texas Health Science Center at Houston's collaborative work-study scholarship program with local hospitals (Kee and Ryser 2001). Students in second clinical semesters were employed as unlicensed personnel by hospitals. The students, as unlicensed personnel, worked to the level of their nursing preparation. Reported benefits for students were academic credit, financial assistance, interaction with multidisciplinary teams, opportunity to refine clinical skills, understanding of nurses' roles and guaranteed interview for positions on graduation (Kee and Ryser 2001). Benefits for practice organizations were skilled help, the opportunity to recruit new nurses and increased interaction with a university nursing program. While nurse education stakeholders in British Columbia were exploring options, the concept of undergraduate student nurse employment was initiated by a group of fourth-year students at the University of Victoria who were completing the course "Nurses Influencing Change." The students were concerned about having enough practice experience to meet increasing nursing competency requirements and their survival as new graduates given workplace realities. Debt load also was a concern because extensive student practicum time limited opportunities for paid employment during the nursing education program. Students found that the idea of paid undergraduate nurse positions, based on the student employment model in Alberta, was supported by nurse leaders, many practising nurses and nursing faculty who also were concerned about meeting patient care standards and adequately preparing nursing students. In 2000, the BC Ministry of Health Services funded an Undergraduate Nurse Demonstration Project (UNDP) - one type of paid employment for undergraduate student nurses - in four Health Service Areas linked with four schools of nursing. A concurrent three-year evaluation study examined the feasibility and outcomes of the UNDP (Gamroth et al. 2004). This paper summarizes the findings of the evaluation. Evaluation Research An Undergraduate Nurse Employment Demonstration Project (UNDP) was implemented in four Health Service Areas in British Columbia with a concurrent evaluation study. This demonstration project comprised the development and implementation of a new position in the BC healthcare system. The position enabled third- and fourth-year nursing students to be employed at their level of education. The purposes of the evaluation were to explore the feasibility and outcomes of this type of paid undergraduate student nurse employment. The three-year project and evaluation included both implementation and outcome analysis. The implementation evaluation design was descriptive and prospective, involving multiple data sources. The outcome evaluation design was quasi-experimental, with intervention and comparison groups. Learning outcomes for undergraduate nurses were increased confidence, organizational ability, competency and ability to work with a team. Workplace outcomes were increased unit morale, help with workload and improved patient care. New graduates with undergraduate nurse experience reported less time required for orientation and transition than other graduates who did not have this experience, and workplace nurses viewed these new graduates as more job-ready than other new graduates. After 21 months, new graduates with undergraduate nurse experience were less likely to move to other employment than other new graduates. Results from the four Health Service Areas indicated that the paid undergraduate nurse position was feasible and that outcomes benefited students, new graduates and workplaces. The undergraduate nurse position is now being implemented throughout all Health Service Areas in British Columbia. By 2000, concerns in British Columbia about the nursing workforce, workplace and patient safety had escalated to the point where diverse stakeholder groups were prepared to work together in new ways to prepare nursing graduates to be more job-ready, to recruit and retain new graduates and to retain existing nurses. Stakeholder groups were administrators, labour organizations, professional associations, educators and government. One idea to support job readiness and retention focussed on the feasibility of implementing cooperative education for nursing students. The effort was unsuccessful owing to lack of funding, but resulted in a review of the literature on cooperative education and other work-study programs. Cooperative education connects classroom learning with paid work experience for the purpose of enhancing students' education (Fitt and Heverly 1990; Heinemann and De Falco 1992; Ryder 1987). Reported benefits for students were improved job preparation and graduate retention (Ishida et al. 1998), additional staffing and reduction in orientation time (Cusack 1990; Ishida et al. 1998), increased practice judgment (Cusack 1990; Siedenberg 1989) and better workload management (Ross and Marriner 1985). A work-study model reported in the literature offered benefits similar to those of cooperative education, with greater flexibility in design. An example was the University of Texas Health Science Center at Houston's collaborative work-study scholarship program with local hospitals (Kee and Ryser 2001). Students in second clinical semesters were employed as unlicensed personnel by hospitals. The students, as unlicensed personnel, worked to the level of their nursing preparation. Reported benefits for students were academic credit, financial assistance, interaction with multidisciplinary teams, opportunity to refine clinical skills, understanding of nurses' roles and guaranteed interview for positions on graduation (Kee and Ryser 2001). Benefits for practice organizations were skilled help, the opportunity to recruit new nurses and increased interaction with a university nursing program. While nurse education stakeholders in British Columbia were exploring options, the concept of undergraduate student nurse employment was initiated by a group of fourth-year students at the University of Victoria who were completing the course "Nurses Influencing Change." The students were concerned about having enough practice experience to meet increasing nursing competency requirements and their survival as new graduates given workplace realities. Debt load also was a concern because extensive student practicum time limited opportunities for paid employment during the nursing education program. Students found that the idea of paid undergraduate nurse positions, based on the student employment model in Alberta, was supported by nurse leaders, many practising nurses and nursing faculty who also were concerned about meeting patient care standards and adequately preparing nursing students. |
Female patients complaining about hair loss: documentation of defective scalp hair dynamics with contrast-enhanced phototrichogram.
The complaint of chronic hair loss frequently affects female subjects and there is little or no objective technology available in the general dermatology or even in the hair clinics to guide the observer in the management of the patient. The purpose of this report is to share the results of refined hair growth measurements that were collected in 92 female subjects complaining about hair loss. Clinically they were classified as having a patterned hair loss according to Ludwig (L; n=50), diffuse hair loss (D; n=13) or no visible hair loss but complaining of hair shedding (N; n=29). Two scalp sites on the top of the head and one occipital site were investigated after clipping by close-up photography before and after a hair dye (contrast enhancement, CE). Forty-eight hours later a new photograph was taken after CE in view of phototrichogram analysis (CE-PTG). Finally a last hair clip was performed 30 days later and hair thickness and length determined for linear growth measurements (LHGR). Herein we confirm that the top of the head shows usually a higher hair density than occipital sites, a physiological observation that applies both to men and women. From the technological perspective, we also document that CE improves hair detection in all sites. Interestingly, in affected patients (L and D) the relative increase of hair counts after CE was much higher (range +22.4% to +28.3%) compared with apparently unaffected females (N; range +8.2% to +9.7%). This increase in hair counts was only due in part to the presence of less pigmented thinning hair (thickness less than 40 microm). Such thin hairs were found in statistically significantly higher proportions in younger patients with mildly severe (grade I) patterned alopecia (Ludwig: L). In other patients with hair loss and in more severe forms of patterned alopecia - especially in older patients - the thin hair is not detected in abnormal proportions. In all sites slower growth rates and decreased anagen percentages indicate a defective hair replacement programme distinguishing L patterns from diffuse hair loss and from apparently unaffected patients complaining of chronic hair loss. Globally, we also noted that increasing age is associated with significant regression of scalp hair (decreased hair counts, thinner hair and slower LHGR). On the basis of the present data together with female data from the literature and our own studies in male subjects, we suggest a three-step mechanism leading to hair loss 1. Shortening of growth phase the hair cycle with maintained thick hair, i.e. more frequent hair cycling that leads to more hair shedding. 2. Intermittent production of short thin hair, i.e. morphological evidence of miniaturisation. 3. Very occasional or almost no hair production, i.e. dormant follicles or irreversible follicular atrophy. Depending on the genetic background, hormonal microenvironment in the scalp and conditioning of individual hair follicle bio-responses, female and male patterned hair loss may end up into different phenotypes. |
Fate of excited probes in micellar systems.
This article presents studies on the photophysical and photochemical behavior of probes within micellar systems: organized emulsifier/polymer aggregates; the intra- and interpolymer association of amphiphilic polymers; monomer-swollen micelles (microdroplets); and the interfacial layer. Pyrene (Py) as a probe is particularly attractive because of its ability to measure the polarity of its microenvironment. Dipyme yields information on the microviscosity of micellar systems. Probes such as laurdan and prodan can be used to explore the surface characteristics of micelles or microdroplets. The dansyl group has a special photophysical property that gives information about the local polarity and mobility (viscosity) of the microenvironment. The organized association of amphiphilic polymer and emulsifier introduces a heterogeneity in the local concentration of the reactants. This heterogeneity also results from the attractive interaction between hydrophilic monomer and emulsifier in the case when the monomer carries a positive charge and the counterpart a negative one, and vice versa. Some emulsifiers can bind to the amphiphilic copolymers by simple partitioning between the aqueous phase and the polymer--non-cooperative association. The interaction between micelles (microdroplets) and charged polymers leads to the formation of mixed micelles. Binding emulsifiers to these polymers was detected at emulsifier concentrations much below the critical micellar concentration (CMC). Emulsifiers often interact cooperatively with polymers at the critical aggregation concentration (CAC) below the CMC, forming micelle-like aggregates within the polymer. The CAC can be taken as a measure of interaction between the emulsifier and polymer. A decrease in the monomer fluorescence intensity of probe-labeled polymer results from increased excimer formation, or higher aggregates within the unimolecular polymeric micelles. An increase in the monomer fluorescence intensity of probe-labeled polymer within the micellar system can be ascribed to shielding of the probe chromophores by emulsifier micelles. The quenching of probe emission by (un)charged hydrophilic monomer depends on partitioning of the monomer between the aqueous phase and the micelles. Penetration of reactants into the interfacial layer determines the quenching of the hydrophobic probe by hydrophilic quencher, or vice versa. Quenching depends on the thickness, density and charge of the interfacial layer. Compartmentalization prevents the carbonyl compound and unsaturated monomer from coming into sufficiently close contact to allow singlet or triplet-monomer interaction. All negatively charged carbonyl probe molecules are quenched with significantly lower rates than the parent neutral hydrophobic benzophenone molecules, which were located further inside the aggregates. This results from the different conformation and allocation of reactants within the micellar system. In the reverse micelles, quenching depends on the amount of water in the interfacial layer and the total area of the water/oil interface. |
Benchmarking the quality of schizophrenia pharmacotherapy: a comparison of the Department of Veterans Affairs and the private sector.
Comparing quality of care between large health care systems is important for health systems management. This study used measures of the quality of pharmacotherapy for patients with schizophrenia and compared these measures across a sample of patients from the Department of Veterans Affairs (VA) and the private sector. A random sample of all patients diagnosed with schizophrenia in the VA during fiscal year (FY) 2000 was identified using administrative data. In the private sector, a sample of patients diagnosed with schizophrenia in 2000 was identified using MEDSTAT's MarketScan database. For both groups, use of antipsychotic medications was studied and measures of the quality of pharmacotherapy were constructed, including whether patients were prescribed any antipsychotic medication, one of the newer atypical antipsychotics, and whether dosing adhered to established treatment recommendations. These measures were compared across the two groups using logistic regression models, controlling for age, gender, and comorbid diagnoses. Most patients with a diagnosis of schizophrenia (82% in the VA and 73% in the private sector) received an antipsychotic medication, usually one of the newer atypical drugs. Patients in the VA were more likely to be dosed above treatment recommendations, and less likely to be dosed below treatment recommendations. Overall, differences in proportion schizophrenia patients dosed according to recommendations were not statistically different across the two systems (60% in the VA, 58% in the private sector). Differences between the two systems were mixed, with the VA outperforming the private sector with respect to some measures and doing worse on others. Although the VA and the private sector were comparable with respect to the quality measures used in this study, there is room for improvement in both systems. Treatment recommendations are based on the best available clinical evidence of effectiveness and safety. Quality of care might be improved with better adherence to these recommendations. Relatively low rates of adherence to treatment recommendations may be due to lack of awareness of these recommendations among prescribing physicians, or a belief that the recommendations are inadequate. To the extent that low rates of adherence to treatment recommendations are caused by a lack of awareness among physicians, policies should be developed to disseminate this information and encourage the appropriate use of these medications. Further research is needed to understand physician prescribing decisions for these medications. To the extent that physicians feel treatment recommendations for these drugs are inadequate, further research is needed to refine the recommendations. |
Reversal of anemia by erythropoietin therapy retards the progression of chronic renal failure, especially in nondiabetic patients.
Therapy with human recombinant erythropoietin (EPO) has been accepted as effective for renal anemia in dialysis patients. However, studies in rats have shown that correcting anemia with EPO may affect the progression of renal dysfunction. In humans, however, the effect of EPO on residual renal function is a matter of controversy. We, therefore, investigated whether the long-term administration of EPO to predialysis patients influences residual renal function. Anemic patients at the predialysis stage with a serum creatinine (Cr) concentration ranging from 2 to 4 (average 2.9) mg/dl and a hematocrit (Ht) of less than 30% were randomly assigned to two groups which consisted of anemic patients not treated with EPO (group I, untreated anemic controls, n = 31) and anemic patients treated with EPO (group II, treated anemics, n = 42). Patients with nonsevere or moderate anemia (Ht > 30%) with a Cr ranging from 2 to 4 (average 2.6) mg/dl were also recruited as nonanemic controls (group III, untreated nonanemic controls, n = 35). Blood pressure was controlled to the same degree among the three groups by combined treatment with calcium antagonists and angiotensin-converting enzyme inhibitors. All patients were kept strictly on a low-protein (0.6 g/kg/day) and a low-salt (7 g/day) diet. The degree of control of dietary protein and blood pressure and the frequency of angiotensin-converting enzyme inhibitor administration were comparable among the three groups. The primary end point for each patient was a doubling of the baseline Cr which yielded cumulative renal survival rates which were plotted against time. Ht rose significantly from 27.0+/-2.3 to 32.1+/-3.2% in group II (n = 42, p < 0.001) with a rate of increase of 0.4+/-0.06%/week. However, it declined from 27.9+/-1.8 to 25.3+/-1.9% in group I (n = 31, p < 0.001) and from 35.9+/-3.5 to 32.2+/-3.9% in group III (n = 35, p < 0.001). Cr doubled in 26 patients (84%) in group I as compared with 22 (52%) in group II and 21 (60%) in group III. The cumulative renal survival rates in groups II and III were significantly better than that in group I: p = 0.0003 (group I vs. group II) and p = 0.0024 (group I vs. group III). However, there was no difference in the renal survival rate between groups II and III (p = 0.3111). The better survival rate obtained in group II was attributable to the better survival rate for the nondiabetic patients in this group. The present study suggests that anemia, per se, is a factor in the progression of end-stage renal failure and that reversal of anemia by EPO can retard the progression of renal failure, especially in nondiabetic patients, provided that blood pressure control, rate of increase in Ht, and dietary protein restriction are appropriate. |
Properties of serial ultrasound clinical diagnostic pathway in suspected appendicitis and related computed tomography use.
The primary objective was to determine the diagnostic accuracy of a serial ultrasound (US) clinical diagnostic pathway to detect appendicitis in children presenting to the emergency department (ED). The secondary objective was to examine the diagnostic performance of the initial and interval US and to compare the accuracy of the pathway to that of the initial US. This was a prospective cohort study of 294 previously healthy children 4 to 17 years old with suspected appendicitis and baseline pediatric appendicitis scores of ≥2, who were managed with the serial US clinical diagnostic pathway. This pathway consisted of an initial US followed by a clinical reassessment in each patient and an interval US and surgical consultation in patients with equivocal initial US and persistent concern about appendicitis. The USs were interpreted by published criteria as positive, negative, or equivocal for appendicitis. Children in whom this pathway did not rule in or rule out appendicitis underwent computed tomography (CT). Cases with missed appendicitis, negative operations, and CTs after the pathway were considered inaccurate. The primary outcome was the diagnostic accuracy of the serial US clinical diagnostic pathway. The secondary outcomes included the test performance of the initial and interval US imaging studies. Of the 294 study children, 111 (38%) had appendicitis. Using the serial US clinical diagnostic pathway, 274 of 294 children (93%, 95% confidence interval [CI] = 90% to 96%) had diagnostically accurate results: 108 of the 111 (97%) appendicitis cases were successfully identified by the pathway without CT scans (two missed and one CT), and 166 of the 183 (91%) negative cases were ruled out without CT scans (14 negative operations and three CTs). The sensitivity of this pathway was 108 of 111 (97%, 95% CI = 94% to 100%), specificity 166 of 183 (91%, 95% CI = 87% to 95%), positive predictive value 108 of 125 (86%; 95% CI = 79% to 92%), and negative predictive value 166 of 169 (98%, 95% CI = 96% to 100%). The diagnostic accuracy of the pathway was higher than that of the initial US alone (274 of 294 vs. 160 of 294; p < 0.0001). Of 123 patients with equivocal initial US, concern about appendicitis subsided on clinical reassessment in 73 (no surgery and no missed appendicitis). Of 50 children with persistent symptoms, 40 underwent interval US and 10 had surgical consultation alone. The interval US confirmed or ruled out appendicitis in 22 of 40 children (55.0%) with equivocal initial US, with one false-positive interval US. The serial US clinical diagnostic pathway in suspected appendicitis has an acceptable diagnostic accuracy that is significantly higher than that of the initial US and results in few CT scans. This approach appears most useful in children with equivocal initial US, in whom the majority of negative cases were identified at clinical reassessment and appendicitis was diagnosed by interval US or surgical consultation in most study patients. |
Cellular versus myocardial basis for the contractile dysfunction of hypertrophied myocardium.
Contractile dysfunction has been demonstrated in many previous studies of experimental right ventricular pressure-overload hypertrophy; however, given the complex changes that occur both in the cardiac muscle cell and in the multiple components of the cardiac interstitium, it is not clear whether the contractile dysfunction observed is an intrinsic property of the cardiac muscle cell or whether it is the result of a mechanically normal cardiac muscle cell contracting within an abnormal interstitial environment. The purpose of the present study was to examine the contractile behavior of cardiac muscle cells, or cardiocytes, isolated from seven cat right ventricles that were pressure-overloaded by banding the pulmonary artery; right ventricular cardiocytes from seven sham-operated cats served as controls. Cardiocytes were obtained from these cats via standard cell isolation procedures; contractile function of the cardiocytes in response to graded viscous external loads was defined by laser diffraction. The cells were stimulated to contract at a frequency of 0.25 Hz, using 100-microA direct current pulses of alternating polarity. Hypertrophied right ventricular cardiocytes obtained from banded cats showed marked systolic contractile abnormalities in comparison with right ventricular cardiocytes from sham-operated cats. The peak velocity of sarcomere shortening for the control and hypertrophied cardiocytes in 1-cp superfusate was 3.6 +/- 0.2 and 2.1 +/- 0.1 microns/sec, respectively (p less than 0.001); the maximum extent of sarcomere shortening for the control and hypertrophied cardiocytes was 0.21 +/- 0.01 and 0.14 +/- 0.01 microns, respectively (p less than 0.001). Further, the time to peak shortening in the 1-cp superfusate was significantly longer for the hypertrophied cardiocytes (150.1 +/- 3.3 versus 160.4 +/- 3.7 msec; p less than 0.04). When the relengthening properties of the cells were examined in the 1-cp superfusate, there were significant differences between cardiocyte groups. The peak rate of sarcomere relengthening was 3.5 +/- 0.2 microns/sec in the control cardiocytes and 2.2 +/- 0.17 microns/sec in the hypertrophied cardiocytes (p less than 0.001). Similarly, the time to peak velocity of sarcomere relengthening (48.8 +/- 1.8 versus 57.9 +/- 2.9 msec) and the time to 50% maximal sarcomere relengthening (57.1 +/- 3.1 versus 67.1 +/- 3.1 msec) were both significantly prolonged for the hypertrophied cardiocytes (p less than 0.02). This study shows for the first time that the contractile defect in this model of right ventricular pressure-overload hypertrophy is intrinsic to the cardiac muscle cell itself. This finding provides a basis for further, more focused investigations designed to determine the mechanisms responsible for the contractile dysfunction observed in this form of experimental cardiac hypertrophy. |
High-Nuclearity Lanthanide-Containing Clusters as Potential Molecular Magnetic Coolers.
High-nuclearity cluster-type metal complexes are a unique class of compounds, many of which have aesthetically pleasing molecular structures. Their interesting physical and chemical properties arise primarily from the electronic and/or magnetic interplay between the component metal ions. Among the extensive studies in the past two decades, those on lanthanide-containing clusters, lanthanide-exclusive or heterometallic with transition metal elements, are most notable. The research was driven by both the synthetic challenges for these generally elusive species and their intriguing magnetic properties, which are useful for the development of energy-efficient and environmentally friendly magnetic cooling technologies. Our efforts in this vein have been concentrated on developing rational synthetic methods for high-nuclearity lanthanide-containing clusters. By means of the now widely adopted approach of "ligand-controlled hydrolysis" of lanthanide ions, a great variety of cluster-type lanthanide hydroxide complexes had been prepared in the first half of this developing period (1999-2006). In this Account, our efforts since 2007 are summarized. These include (1) further development of synthetic strategies in order to expand the ligand scope and/or to increase the nuclearity (>25) of the cluster species and (2) magnetic studies pertinent to the pursuit of materials with a large magnetocaloric effect (MCE). Specifically, with the hope of expanding the family of ligands and producing clusters of previously unknown structures, we tested under hydrothermal or solvothermal conditions the use of readily available yet not commonly used ligands for controlling lanthanide hydrolysis; such ligands, carboxylates as mundane examples, tend to form insoluble complexes prior to any possible hydrolysis. We have also validated the use of preformed transition metal complexes as metalloligands for subsequent control of lanthanide hydrolysis toward heterometallic 3d-4f clusters. Furthermore, we demonstrated using ample examples that the presence of small anions as templates is essential to the assembly of high-nuclearity lanthanide-containing clusters and that maintaining a low concentration of the anion template(s) is a key to such success. It has been found that slow production/release of such anion templates by in situ ligand decomposition or absorption of atmospheric CO2 is effective in preventing precipitation of their lanthanide salts, allowing not only controllable lanthanide hydrolysis but also gradual and modular assembly of the giant cluster species. Magnetic studies targeting potential applications of such clusters as molecular magnetic coolers have also been conducted. The results are summarized in the second portion of this Account in an effort to establish a certain magneto-structure relationship. Of particular relevance is the possible correlation between MCE (evaluated using the isothermal magnetic entropy change, -ΔSM) and magnetic density, and the intracluster antiferromagnetic exchange coupling. We have also made some preliminary attempts at preparing processable and practically useful materials in the form of a monodisperse core-shell nanostructure. We succeeded in encapsulating a single nanosized heterometallic molecular cluster in a nanoshell of silica. It was found that such passivation not only helped stabilize the cluster but also reduced the magnetic interactions between individual clusters. These effects are reflected in the slightly enhanced value of -ΔSM for the core-shell composite over the parent unprotected cluster. |
Diet-induced and physiologically occurring hypercholesterolemias in the spontaneous hypothyroid European badger (Meles meles L.): a density gradient study of lipoprotein profile.
As previously shown in this laboratory (Laplaud, P. M. et al. J. Lipid Res. 1980. 21: 724-738), the European badger is, with regard to its plasma lipid transport system, an original and complex animal of great potential interest to lipoprotein research. In an effort to study the response of this animal to cholesterol feeding, we gave a diet supplemented with 1% cholesterol to six male badgers (group H) during the late fall period when spontaneous hypercholesterolemia and hypothyroidism occur. Six more male animals of similar age received the standard diet (group C) and were simultaneously used as controls. Plasma lipids were measured using enzymatic methodologies, while the use of a recently described density gradient ultracentrifugation technique allowed detailed examination of lipoprotein composition and polyacrylamide gel electrophoresis of lipoproteins and tetramethylurea-soluble apoproteins in the fractions. The results suggest the superimposition, in H badgers, of the spontaneous and diet-induced hypercholesterolemias, maximum levels being reached in December in both C and H groups. While the two groups were very similar at the beginning of the experiment, highly significant differences (P < 0.01) were subsequently observed between C and H animals in plasma cholesterol and phospholipid concentrations. Density gradient ultracentrifugation provided evidence for the following diet-induced changes in lipoprotein profile: 1) a twofold increase in cholesteryl esters in particles of d < 1.006 g/ml; 2) the occurrence of large amounts of supplementary cholesterol-rich low density lipoproteins, mainly in the 1.019-1.027 g/ml region; 3) an increase in the 1.039-1.055 g/ml low density lipoproteins; and 4) a change in the ratio of the concentrations of high density lipoproteins of d 1.065-1.100 g/ml and d 1.100-1.162 g/ml, to the benefit of the former. Electrophoresis of the density gradient fractions revealed marked heterogeneity, especially in the low density part of the spectrum. Electrophoresis of the low molecular weight, tetramethylurea-soluble apoproteins failed to show marked differences between C and H badgers. However, chromatographic determination of the proportion of apoB in the protein moiety of the two main low density components showed that 1) it was consistently low, 2) its contribution to the higher density fraction (d 1.039-1.046 g/ml) was unaffected by the hypercholesterolemic diet (being about 25% in both C and H animals), and 3) its contribution to the lower density fraction (d 1.019-1.027 g/ml) decreased under the same nutritional conditions, representing about 20% in C as compared to about 10% in H badgers.-Laplaud, P. M., Beaubatie, and D. Maurel. Dietinduced and physiologically occurring hypercholesterolemias in the spontaneous hypothyroid European badger (Meles meles L.): a density gradient study of lipoprotein profile. |
[Hyperinsulinism induced with glucocorticoid--a study on using a perifusion system of isolated islets in rats (author's transl)].
In order to elucidate the mechanism of hyperinsulinism following a treatment with glucocorticoid, insulin secretion induced with glucose or tolbutamide was investigated by a perifusion experiment on isolated islets of rats. The results are summarized as follows: 1. The fasting blood glucose level was significantly higher on the 2nd day (174.0 +/- 11.8 mg/dl) and 3rd day (179.6 +/- 9.5 mg/dl) in the glucocorticoid treated rats, than it was in the control rats (129.0 +/- 12.0 mg/dl). The serum insulin levels began to increase from the first day following the glucocorticoid treatment (17.2 +/- 1.3 microU/ml in the control rats, 27.6 +/- 2.1 microU/ml on the 1st day, 32.4 +/- 3.9 microU/ml on the 2nd day, and 34.5 +/- 1.4 microU/ml on the 3rd day). 2. The insulin content of the islets decreased with the glucocorticoid treatment (765.6 +/- 34.5 microU/islet in the control rat, 576.6 +/- 25.0 microU/islet on the 1st day, 629.2 +/- 36.9 microU/islet on the 2nd day, and 482.0 +/- 43.5 microU/islet on the 3rd day). 3. In the perifusion experiment, a biphasic pattern of insulin secretion was demonstrated with the stimulation of glucose in the control and glucocorticoid treated rats. A remarkable enhancement of insulin secretion was observed by the stimulation of 100 mg/dl glucose. The amount of insulin secretion at the first phase (up to 7 min. after the glucose stimulation) was 2.9 +/- 0.5 microU/islet on the 1st day, 2.7 +/- 0.3 microU/islet on the 2nd day and 3.8 +/- 0.1 microU/islet on the 3rd day; these amounts were high compared with that of 1.8 +/- 0.1 microU/islet in the control rat. The amount of insulin secretion at the second phase (8 to 60 min. after the glucose stimulation) was 28.5 +/- 2.5 microU/islet on the 1st day, 37.1 +/- 3.3 microU/islet on the 2nd day and 41.3 +/- 1.8 microU/islet on the 3rd day; these amounts were higher when compared with that of 24.7 +/- 0.7 microU/islet in the control rat. 4. The monophasic insulin secretion from isolated islets by the stimulation of tolbutamide was enhanced with the treatment of glucocorticoid. These results indicate that glucocorticoid directly enhances insulin secretion from the pancreatic islets at the physiological concentration of blood glucose, which seems to be an important factor in the occurrence of hyperinsulinemia associated with glucocorticoid therapy. |
Increased dispersion of ventricular repolarization and ventricular tachyarrhythmias in the globally ischaemic rabbit heart.
Contemporary concepts of ischaemic ventricular tachyarrhythmias (VTA) are based on increased electrophysiological heterogeneity of the myocardium. We developed a multi-site monophasic action potential recording system for an isolated rabbit heart to study the effects of global ischaemia on the electrophysiological properties at different ventricular sites simultaneously. The hearts were paced from the right ventricle (RV), and conduction time (CT), action potential duration (APD) and total repolarization time (TRT = [CT + APD]) were measured during normal perfusion and ischaemia. The dispersion of these parameters was calculated as the maximal difference between simultaneous recordings. Inducibility of VTA by programmed extrastimulation (ES) was investigated under normal and ischaemic conditions. During global ischaemia, CT increased progressively, showing a faster and greater increase at the left ventricle (LV) than at the RV. After 10 min the prolongation of CT reached a plateau at the LV while it continued to rise in the RV. The dispersion of CT increased from 14.5 +/- 2.7 ms during normal perfusion to a maximum of 79.8 +/- 17.2 ms after 14 min of ischaemia (P < 0.0001). APD was uniform at the three sites (190.9 +/- 10.2, 185.0 +/- 8.6 and 179.3 +/- 9.8 ms, ns) during normal perfusion but changed non-uniformly during ischaemia. There was a transient lengthening of APD until 1 and 3 min of ischaemia at the LV sites followed by a rapid shortening of APD. At the RV site, APD continued to increase until 5 min of ischaemia and then shortened gradually. Consequently, dispersion of APD showed a rapid initial rise from 17.7 +/- 2.7 ms to 77.8 +/- 10.2 ms (P < 0.0001) followed by a slower final increase. TRT was uniform during normal perfusion (210.4 +/- 10.3, 213.1 +/- 7.8, 212.1 +/- 10.3 ms, ns) but became non-uniform during global ischaemia. The dispersion of TRT increased from 15.4 +/- 4.2 ms to 92.6 +/- 23.2 ms (P < 0.0001) during 14 min of global ischaemia. Both CT and APD contributed independently to TRT and could either augment or partially compensate for the ischaemic alterations of the other parameter. ES induced VTA only during ischaemia (3.7 +/- 1.1 VTA per heart, P < 0.0001) at coupling intervals between 220 and 380 ms. The dispersion of TRT of the last regular beat preceding VTA was 67.7 +/- 17.4 ms (P < 0.001). ES which triggered VTA showed a more than two-fold increase of CT dispersion compared to the last steady state beat (122.7 +/- 29.4%, P = 0.0001).(ABSTRACT TRUNCATED AT 400 WORDS) |
Mitigation of cocaine-mediated mitochondrial damage, defective mitophagy and microglial activation by superoxide dismutase mimetics.
Although cocaine exposure has been shown to potentiate neuroinflammation by upregulating glial activation in the brain, the role of mitophagy in this process remains an enigma. In the present study, we sought to examine the role of impaired mitophagy in cocaine-mediated activation of microglia and to determine the ameliorative potential of superoxide dismutase mimetics in this context. Our findings demonstrated that exposure of mouse primary microglial cells (mPMs) to cocaine resulted in decreased mitochondrial membrane potential, that was accompanied by increased expression of mitophagy markers, PINK1 and PRKN. Exposure of microglia to cocaine also resulted in increased expression of DNM1L and OPTN with a concomitant decrease in the rate of mitochondrial oxygen consumption as well as impaired mitochondrial functioning. Additionally, in the presence of cocaine, microglia also exhibited upregulated expression of autophagosome markers, BECN1, MAP1LC3B-II, and SQSTM1. Taken together, these findings suggested diminished mitophagy flux and accumulation of mitophagosomes in the presence of cocaine. These findings were further confirmed by imaging techniques such as transmission electron microscopy and confocal microscopy. Cocaine-mediated activation of microglia was further monitored by assessing the expression of the microglial marker (ITGAM) and the inflammatory cytokine (Tnf, Il1b, and Il6) mRNAs. Pharmacological, as well as gene-silencing approaches aimed at blocking both the autophagy/mitophagy and SIGMAR1 expression, underscored the role of impaired mitophagy in cocaine-mediated activation of microglia. Furthermore, superoxide dismutase mimetics such as TEMPOL and MitoTEMPO were shown to alleviate cocaine-mediated impaired mitophagy as well as microglial activation. Abbreviations: 3-MA: 3-methyladenine; Δψm: mitochondrial membrane potential; ACTB: actin, beta; AIF1: allograft inflammatory factor 1; ATP: adenosine triphosphate; BAF: bafilomycin A1; BECN1: beclin 1, autophagy related; CNS: central nervous system; DNM1L: dynamin 1 like; DMEM: Dulbecco modified Eagle medium; DAPI: 4,6-Diamidino-2-phenylindole; DRD2: dopamine receptor D2; ECAR: extracellular acidification rate; FBS: fetal bovine serum; FCCP: Trifluoromethoxy carbonylcyanide phenylhydrazone; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; IL1B: interleukin 1, beta; IL6: interleukin 6; ITGAM: integrin subunit alpha M; MAP1LC3B: microtubule-associated protein 1 light chain 3 beta; mPMs: mouse primary microglial cells; MRC: maximal respiratory capacity; NFKB: nuclear factor kappa B; NLRP3: NLR family pyrin domain containing 3; NTRK2: neurotrophic receptor tyrosine kinase 2; OCR: oxygen consumption rate; OPTN: optineurin; PBS: phosphate buffered saline; PINK1: PTEN induced putative kinase 1; PRKN: parkin RBR E3 ubiquitin protein ligase; ROS: reactive oxygen species; siRNA: small interfering RNA; SQSTM1: sequestosome 1; TNF: tumor necrosis factor. |
On the role of water molecules in the interface between biological systems and polymers.
The excellent biocompatibility of PMEA was ascribed by Tanaka to the predominant population of intermediate water in the hydrated polymer matrix. The intermediate water concept was examined using the 'nano-plate model' on the basis of new results (by Morita) of a time-resolved IR study on the water sorption process into PMEA. The examination showed that the image picture proposed by Tanaka concerning the role of intermediate water was in consistent with experimental results so far obtained. Morita showed that the intermediate water exhibited a strong peak at 3400 cm(-1) in its IR spectrum. Water sorption profiles of MMA, PEG and PMVE were found to be similar to that of PMEA. It was shown that the biocompatibility of these polymers could be explained by the intermediate water concept. It was also pointed out that PVP and PDMAA have a considerable amount of intermediate water under appropriate circumstances. The PHEMA-water system showed neither clear peak for cold crystallization in DSC chart, nor the strong peak at 3400 cm(-1) in its IR spectrum, because the PHEMA system did not contain enough intermediate water to show similar behavior to PMEA. The hydrated PHEMA matrix contains a stable network structure of water molecules including the nodes of OH groups of its side-chains. In the stable network system, most water molecules should be hydrogen bonded strongly to form non-freezing water, but not intermediate water. The inferior biocompatibility of PHEMA was ascribed to the stable network structure of water molecules. Some of the PHEMA co-polymers, on the other hand, were found to have highly improved biocompatibility. Mechanism for the improvement was discussed in terms of loosening the network structure, which could be brought about by introducing ionic groups or branching to the polymer chains through co-polymerization with appropriate 'key monomers'. The mobility of polymer chains, as well as the population of three kinds of water in polysaccharide molecules in aqueous medium could change in response to their chemical structure such as nature of ionic groups, the degree of branching, etc. Polysaccharides located at the utmost-outer layer of blood cells probably possess a loosened network structure to form soft biological surface where intermediate water predominates. Cellulose, on the other hand, has a common feature with PHEMA in the sense of predominance of the non-freezing water in its hydrated system. Note: The word 'biocompatibility' is used in general as the term evaluating properties of materials which do not cause adverse effect when the materials come into contact with living organisms, such as proteins, biological cells and tissues. This review paper primarily deals with 'biocompatibility' of polymer materials against various biological elements in blood flow system. |
Clinical outcomes after burns in elderly patients over 70 years: A 17-year retrospective analysis.
In the United Stated population >70years is likely to double by the year 2050. Elderly population (>70years) are most vulnerable to burns and outcomes following such injuries in this special group is poorly studied. This study aimed to look at outcomes following burns in patients >70years over a period of 17 years. Data on 6512 patients admitted to a Level I Burn Center between 1995 and 2011 was analyzed. Age, gender, ethnicity, TBSA, burn etiology, hospital and burn intensive care unit (ICU) length of stay (LOS) and status at discharge were abstracted. Three broad categories were created based on presence or absence of smoke inhalation, No smoke inhalation (Group A), smoke inhalation only (Group B) and smoke inhalation with burn injury (Group C). Differences were analyzed using the student's t-test for continuous variables and Chi-Square test for categorical variables. The study group was comprised of 564 patients, 72.3% in group A, 4.8% in group B and 22.9% in group C formed the study population. The mean age of the patients studied was 80.4±6.7, with female patients being more common (58%). The number of Caucasians (72.9%) was highest in group C compared to other racial groups (p=0.047). Majority of patients in the group B (59.3%) were admitted directly compared to other two groups (group A=24.0%, group B=34.9%, p<0.001). Overall percent total body surface area (% TBSA) and % TBSA third degree burns were higher in group C, whereas % TBSA second degree burns were common in group B (p<0.05). The number ICU admissions, the mean length of ICU stay, mean duration of ventilator support and mean length of hospitalization were all highest in group C patients (p<0.001). The number of discharges to home without home health aide were higher in group A, whereas the number of discharges to nursing home/rehabilitation/extended care facility were higher in group B (p<0.001). The in-hospital mortality (58.1%, p<0.001) and overall burn related mortality (62.8%, p<0.001) were highest in group C. There was no significant difference between the groups for the number of patients converted to hospice care (p=0.21). On multivariate analysis ICU admission (Odds Ratio [OR]=3.7, 95% Confidence Interval [95% CI]=2.1-6.5), ventilator support (OR=7.1, 95% CI=4.1-12.0), and %TBSA >10% (OR=3.1, 95% CI=1.9-5.0) significantly increased mortality. In terms of complications, group C had a significantly higher incidence of pneumonia (18.6%, p<0.001), respiratory failure (17.1%, p=0.001), and sepsis (7.8%, p=0.003). Patients >70 years constitute small (8.6%) but significant number among burn patients. The overall ICU admissions, number of days on ventilator, ICU stay, in-hospital mortality and overall mortality is higher in this group of population even for low % TBSA burns. Presence of smoke inhalation increases mortality. |
Group B streptococcus alters properties of vaginal epithelial cells in pregnant women.
Group B streptococcus (GBS) infection in pregnancy is a major cause of maternal and neonatal morbidity. An understanding of the mechanisms responsible for GBS persistence in the genital tract, as well as recognition of host defenses employed to combat its presence, are crucial to our efforts to reduce maternal GBS colonization and prevent the acquisition of neonatal infections. However, alterations in vaginal immunity in response to GBS colonization in pregnant women remain incompletely defined. Whether GBS modulates autophagy, a major host defense mechanism and contributor to the control of intracellular microbial infections, also remains unclear. We sought to identify differences in the extent of autophagy as well as in the concentration of biomarkers previously shown to be involved in vaginal innate immunity between GBS-positive and GBS-negative pregnant women. We performed a prospective cohort study of healthy pregnant women, who had vaginal secretions obtained at 35-37 weeks of gestation, just prior to the standard GBS rectovaginal sample collection. The contents of the swabs were released into tubes containing 1 mL of sterile phosphate-buffered saline. Samples were centrifuged, and supernatant and cell pellet fractions were collected and stored separately at -80°C until used for analysis. Epithelial cells were then lysed, and the extent of autophagy was determined by measuring the residual level of p62 remaining in the cytoplasm. p62 is a protein that is consumed during autophagy, and so its concentration detectable in the cytoplasm is inversely related to the extent of autophagy induction. The intracellular level of the inducible 70-kDa heat shock protein (hsp70), an inhibitor of autophagy, was also measured. The cell-free fraction was assayed for D- and L-lactic acid, neutrophil gelatinase-associated lipocalin, extracellular matrix metalloproteinase inducer (EMMPRIN), matrix metalloproteinase (MMP)-8, alpha amylase, hyaluronan, and total protein. Laboratory personnel were blinded to all clinical data. There were 145 women included in the study, of which 45 (31%) were culture-positive for GBS. Vaginal cells from GBS-positive women had elevated intracellular levels of p62 (2.1 vs 0.7 pg/mL, P < .01) and hsp70 (16.9 vs 9.6 ng/mL, P = .03) as compared to GBS-negative women. The p62 and hsp70 levels were highly correlated in both groups of subjects (P < .01). In vaginal fluid, concentrations of neutrophil gelatinase-associated lipocalin (1.1 vs 0.7 ng/μg total protein, P = .01), MMP-8 (21.9 vs 11.1 pg/μg total protein, P = .01), and extracellular MMP inducer (8.8 vs 7.2 pg/μg total protein, P = .03) were highest in GBS-positive women. There were no differences in the concentrations of D- and L-lactic acid, alpha amylase, or hyaluronan between the 2 groups of women. The inhibition of autophagy in vaginal epithelial cells by GBS-induced hsp70 production is associated with its persistence. Concurrently, alterations in components known to influence vaginal bacterial colonization or facilitate microbial passage to the upper genital tract also occur in relation to GBS carriage. |
Changes in circulating insulin-like growth factor-I, insulin-like growth factor binding proteins, and leptin in weaned pigs infected with Salmonella enterica serovar Typhimurium.
One of the hallmarks of the pathophysiology of enteric disease in young pigs is reduced growth performance. This reduction in growth is associated with changes in the endocrine somatotropic growth axis. Our laboratory previously demonstrated that circulating insulin-like growth factor-I (IGF-I) was reduced in pigs infected with Salmonella enterica serovar Typhimurium (S. typhimurium) while circulating growth hormone remained unchanged. The objective of the current study was to determine if infection with S. typhimurium also was associated with changes in circulating IGF binding proteins (IGFBP). In addition, pigs experiencing active enteric disease have reduced feed intake. Because this inappetence may be related to systemic appetite reduction signals, we also evaluated circulating leptin in pigs undergoing active S. typhimurium-induced enteric disease. Crossbred pigs were penned in environmentally controlled rooms with free access to feed and water. Following an acclimation period, pigs were gavaged with 10(10) cfu of S. typhimurium (SAL; n=6) or were given a similar volume of sterile growth media (CON; n=6). Rectal temperatures and feed intakes were measured daily through 168 h to track the time course of the response to S. typhimurium infection. Samples of serum were obtained by jugular venipuncture at 0, 24, 48, 96 and 168 h after infection. Sera were frozen until evaluation for IGF-I by immunoradiometric assay (IRMA). In addition, sera were subjected to western ligand blotting utilizing 125I-IGF-I and 125I-IGF-II. Images were evaluated for total IGFBP and IGFBP-3 by densitometric analyses. Rectal temperature was increased in SAL pigs 24h post-infection (P<0.001) but not at other times. Feed intake was reduced in SAL pigs during the intervals 24-72 h (P<0.001) and 96-144 h (P<0.05) after infection. Serum IGF-I, expressed as a percentage of the 0 h concentration, was reduced in SAL pigs versus CON pigs at 48 h (28.1+/-18.7% versus 102.2+/-17.1%; P<0.01) and 96 h (20.0+/-18.7% versus 128.4+/-17.0%; P<0.0001) post-infection. Both total IGFBP and IGFBP-3, as estimated by ligand blotting, also were reduced in infected pigs at 48 h postchallenge (P<0.05). IGFBPs were similar between the two treatments at other sampling times. Concentrations of IGFBP-3 also were estimated utilizing an IRMA for human IGFBP-3. Serum IGFBP-3 was reduced in S. typhimurium-infected pigs at 24 h (P<0.01), 48 h (P<0.001), 96 h (P<0.001), and 168 h (P<0.05). Serum leptin levels were similar between SAL and CON pigs. The data suggest that swine enteric disease is associated with reduced circulating IGF-I and reductions in total IGFBP and IGFBP-3. However, serum leptin was not affected by enteric disease challenge. |
Analysis of patients with longitudinal intestinal lengthening procedure referred for intestinal transplantation.
Longitudinal intestinal lengthening procedures (LILP) in patients with short gut syndrome (SGS) enhances small intestinal peristalsis and decreases bacterial overgrowth without reducing absorptive surface. Therefore, patients theoretically may be easily weaned off TPN. The aim of this study was to evaluate the impact of failed LILP in SGS patients referred for intestinal transplantation. Twenty-seven (11%) of 230 children with SGS and total parenteral nutrition (TPN) dependency evaluated for intestinal transplantation at our institution had undergone LILP. This was performed at a mean age of 1.7 years (range, 1 day to 14.7 years); the mean age at the time of evaluation was 3.3 years (range, 0.4 to 17 years). Two patients underwent LILP immediately after birth. The principle diagnoses producing SGS were gastroschisis (n = 8), intestinal atresia (n = 11), neonatal volvulus (n = 7) and necrotizing enterocolitis (n = 1). Before LILP, the mean length of intestine was 32 cm (range, 8 to 70 cm). Fifteen (56%) patients had jaundice at the time of evaluation. All but one child were considered candidates for intestinal transplantation. The mean intestinal length achieved after LILP was 48 cm (range, 16 to 100). The mean follow-up from the date of LILP was 876 days (range, 109 to 4,109 days). After LILP, only 9 (33%) patients increased their caloric intake through the enteral route by > or =50%, and only 1 patient could be weaned off TPN. In the patients with liver dysfunction at the time of LILP, none recovered. Most of the patients had multiple episodes of sepsis after LILP. Fourteen (52%) of 27 patients underwent intestinal transplantation, 7 combined with a liver allograft because of TPN-induced end-stage liver disease. Six of the transplanted patients are alive and TPN free. Of the remaining 13 (48%) nontransplanted patients, 9 patients died. The main cause of death was TPN-induced liver failure. Three patients are on partial TPN, and only 1 patient was weaned off TPN. The presence of an ileocecal valve did not impact on outcome. Surprisingly, patients with > or =50% of colon at the time of LILP had poorer survival than those with less. Twelve (44%) of 27 patients had surgical complications, and in both patients with LILP performed in the neonatal period it failed immediately with acute complications. There were no differences in patient survival rate for patients with SGS without LILP (n = 203) and those with LILP (n = 27). Based on patients with unsuccessful LILP referred for intestinal transplantation, we believe this procedure should be avoided in the neonatal period, in those patients with liver dysfunction, and when intestinal length is <50 cm. |
[Bacillus subtilis IP 5832 (Flonivin BS) shortens the duration of the carrier state in patients with acute non-typhoid salmonella enteritis].
The objective of this clinical trial was to assess the efficacy and safety of Flonivin BS (Bacillus Subtilis IP 5832) vs. placebo in treatment of patients with acute non-typhoid Salmonella gastroenteritis (ANSG), on adequate diet and parenteral rehydration therapy. The clinical trial was conducted as a multicenter, controlled, randomized, double-blind, prospective clinical trial including 63 patients of both sexes, 20 to 52 years of age, with clinically, epidemiologically and microbiologically diagnosed ANSG, accompanied by diarrhea not longer than two days. Flonivin BS capsules (each capsule containing at least 1 billion of vegetative spores of Bacillus subtilis, strain IP 5832) were administered to 31 patients, while 32 patients received placebo (3 x 2 capsules daily) over a seven day period. Stool cultures were collected on days 7, 14, 21 and 28 for checking the carrier state. The efficacy criteria were based on determining the differences in duration of diarrhea and of the carrier state in Flonivin BS-treated group of patients as compared to the placebo-group. Statistical analysis was performed using Student's-test of proportions for small and large samples. The analysis of the number of patient-weeks by subgroups on days 7, 14, 21 or 28 of the trial in Flonivin BS- and placebo-groups has shown that the rate of patient-weeks of the carrier state was significantly lower in Flonivin BS-treated group as compared to the placebo-group, which was manifested in week 4 of the trial (p < 0.01). The analysis of the rate of positive findings in stool cultures in the groups treated with Flonivin BS vs. placebo by weeks of the confirmed carrier state has shown that Flonivin BS significantly reduces the rate of positive findings in stool cultures in the fourth week from the initiation of treatment (p < 0.05). No differences were noted in duration of diarrhea between the study groups (p > 0.05). It has been concluded that a seven day treatment with Flonivin BS in patients with ANSG is of significance in prevention of a long-term carrier state, as it reduces the number of diseased that remain carriers in the third week after completion of treatment (p < 0.05). A prophylactic administration of Flonivin BS in patients with ANSG has a potential epidemiological significance due to a significant reduction in the number of patient-weeks of the carrier state in population of long-term carriers (p < 0.01). |
[Effect of down-regulation of Oct4 gene on biological characteristics of MDA-MB-231 breast cancer stem cells].
To investigate the effect and significance of down-regulation of Oct4 gene on biological characteristics of MDA-MB-231 breast cancer stem cells. Breast cancer cell line MDA-MB-231 cells were used in this study. Breast cancer stem cells were isolated and enriched by serum-free culture. The obtained stem cells were identified through calculating the percentages of CD44 and CD24 stem cells by FACS and evaluating the paclitaxel resistance in vitro and tumorigenicity in mice. RT-PCR, real-time PCR (qPCR) and Western blot were used to detect Oct4 expression. RNA interference was applied to induce Oct4 down-regulation. The interference experiment set up a control group (no siRNA transfection), negative control group (negative siRNA group, transfection of siRNA sequences without any interfering effect on the cells) and Oct4 siRNA group (transfection of siRNA with interfering effect on the Oct4 gene). Methyl thiazolyl tetrazolium (MTT) and Transwell chamber tests were conducted to detect the proliferation and invasion ability of MDA-MB-231 breast cancer stem cells after Oct4 knock-down, and paclitaxel inhibition test was applied to evaluate drug resistance of MDA-MB-231 breast cancer stem cells after Oct4 knock-down. MDA-MB-231 breast cancer stem cells grew as spheres cultured in serum-free suspension. MDA-MB-231 breast cancer stem cells showed a higher percentage of CD44+/CD24-/low cells (97.2%) than that in MDA-MB-231 breast cancer cells (76.6%) (P < 0.05). The tumor size in mice inoculated with MDA-MB-231 breast cancer stem cells was (124.60 ± 13.65) mm3, significantly larger than that of mice inoculated with breast cancer cells (68.20 ± 9.99 mm3) (P = 0.0007). MDA-MB-231 breast cancer stem cells were less sensitive to paclitaxel inhibition than MDA-MB-231 breast cancer cells showing by 50% inhibitory concentration (IC50) [(4.40 ± 0.48) µg/ml vs. (8.20 ± 0.34) µg/m, P < 0.05]. However, the expression of transcriptional factors Oct4 was higher in MDA-MB-231 breast cancer stem cells than that in breast cancer cells (P < 0.05). The proliferation potential of MDA-MB-231 breast cancer stem cells with Oct4 siRNA interference was significantly lower than that in the negative siRNA and control groups (P < 0.05) from the third day. The invasion ability of MDA-MB-231 breast cancer stem cells with Oct4 siRNA interference was obviously reduced than that in the control and negative siRNA groups shown by number of penetrated cells [(46.52 ± 2.58) vs. (79.67 ± 3.85) and (77.29 ± 2.13) , P < 0.05 for both]. As for resistance to paclitaxel, IC50 of MDA-MB-231 breast cancer stem cells with Oct4siRNA interference was significantly decreased [(4.48 ± 0.22) µg/ml] compared with that in the control [ (7.99 ± 0.59) µg/ml] and negative siRNA group [(8.10 ± 0.68) µg/ml] (P < 0.05 for both). MDA-MB-231 breast cancer cells are successfully obtained by serum-free culture. The proliferation potential, invasion ability and drug resistance of breast cancer stem cells were down-regulated by Oct4 gene knock-down. |
The Timing of Injections Prior to Arthroscopic Rotator Cuff Repair Impacts the Risk of Surgical Site Infection.
Corticosteroid injections are a common treatment for rotator cuff tears. Because of concerns of infection, a surgical procedure is often delayed following injections. The purpose of this investigation was to determine if there is a temporal relationship between corticosteroid injections and the risk of surgical site infection after arthroscopic rotator cuff repair. We hypothesized that the incidence of surgical site infection is higher in patients who received a preoperative injection and this relationship exists in a temporal manner as those patients receiving an injection closer to the operative date have a higher risk of infection. The PearlDiver database was reviewed for patients undergoing arthroscopic rotator cuff repair from 2007 to 2016. Patients were stratified into 2 cohorts: those undergoing arthroscopic rotator cuff repair within 1 year of injection (n = 12,060), and those undergoing arthroscopic rotator cuff repair without prior injection (n = 48,763). Patients with preoperative injections were further stratified by the duration in months that the injection was performed prior to the surgical procedure. Surgical site infection within 6 months of the surgical procedure was recorded. Statistical analysis included chi-square and multivariate binomial logistic regression analyses to identify risk factors for surgical site infection. Results were considered significant at p < 0.05. There was no significant difference in the incidence of surgical site infection in patients receiving a shoulder injection at 0.7% compared with the control cohort at 0.8% (odds ratio [OR], 0.9 [95% confidence interval (CI), 0.7 to 1.1]; p = 0.2). However, patients receiving an injection within 1 month prior to operative management had a significantly higher rate of surgical site infection overall at 1.3% compared with the control group at 0.8% (OR, 1.7 [95% CI, 1.0 to 2.9]; p = 0.04). On multivariate analysis, male sex (OR, 1.7 [95% CI, 1.4 to 1.9]; p = 0.001), obesity (OR, 1.4 [95% CI, 1.2 to 1.6]; p < 0.001), diabetes (OR, 1.3 [95% CI, 1.1 to 1.5]; p < 0.001), smoking status (OR, 1.7 [95% CI, 1.4 to 1.9], p < 0.001), and preoperative corticosteroid injections within 1 month of the surgical procedure (OR, 2.1 [95% CI, 1.5 to 2.7]; p < 0.001) were independent risk factors for development of a surgical site infection. Injections within 1 month of arthroscopic rotator cuff repair significantly increases the risk of surgical site infection. However, there is no increased risk of infection if the surgical procedure is delayed by 1 month following an injection. Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence. |
Imaging, dosimetry, and radioimmunotherapy with iodine 131-labeled anti-CD37 antibody in B-cell lymphoma.
This study was undertaken to evaluate the tumor targeting, toxicity, and therapeutic potential of the anti-B-cell-reactive monoclonal antibody MB-1 (anti-CD37) labeled with iodine 131 given in a nonmarrow ablative dose range in B-cell lymphoma patients who relapsed after chemotherapy. Twelve patients with MB-1-reactive tumors were infused first with 40 mg of trace-labeled (3 to 7 mCi) MB-1. Ten patients who had no serious toxicity postinfusion and who had successful tumor imaging on serial gamma scans then received at least one 40-mg radioimmunotherapy (RIT) dose (25 to 161 mCi). Tracer estimates of delivered whole-body dose (WBD) were used in prescribing a millicurie RIT dose for seven patients. Eleven patients had positive tumor imaging after a tracer dose, including patients with bulky tumors and/or large tumor burdens (> or = 1 kg) +/- splenomegaly. However, overall sensitivity for the detection of known tumor sites was only 39%. In six of eight patients with dose-assessable tumors, the radiation dose to at least one tumor was 1.1 to 3.1 times higher than to any normal organ, excluding the spleen for a 40-mg tracer dose. Tracer-dose toxicities included reversible glossal edema in one patient, grade 3 hepatic transaminasemia in another, and early drops in both circulating B and T cells (with decreases in B cells more pronounced) in nearly all patients. RIT toxicity was primarily myelosuppression (especially thrombocytopenia), which had a delayed onset and protracted recovery (without significant recovery until at least 2 months post-RIT). Grade 3 myelosuppression in two of two patients who were treated at a tracer-projected 50-cGy WBD level (133 and 149 mCi) precluded further planned RIT dose escalation. Less myelosuppression was generally observed in patients who were treated at < or = 40-cGy WBD levels. Antimouse antibodies developed in two patients. Six patients had tumor responses post-RIT. Four had responses that lasted more than 1 month (2 to 6 months), which included one complete response, one partial response, one minor response, and one mixed response. Responses seemed to occur more frequently in imaged tumors than in nonimaged tumors. The most durable response occurred in a patient who had the best antibody targeting to tumor. Although 131I-MB-1 has limited diagnostic value, it can produce tumor responses at nonmarrow ablative RIT doses. Further studies that focus on improving tumor targeting with this or other B-cell-reactive radiolabeled antibodies and on ameliorating the myelosuppression associated with the RIT-dosing approach used in this trial are warranted. |
Comparing models for perfluorooctanoic acid pharmacokinetics using Bayesian analysis.
Selecting the appropriate pharmacokinetic (PK) model given the available data is investigated for perfluorooctanoic acid (PFOA), which has been widely analyzed with an empirical, one-compartment model. This research examined the results of experiments [Kemper R. A., DuPont Haskell Laboratories, USEPA Administrative Record AR-226.1499 (2003)] that administered single oral or iv doses of PFOA to adult male and female rats. PFOA concentration was observed over time; in plasma for some animals and in fecal and urinary excretion for others. There were four rats per dose group, for a total of 36 males and 36 females. Assuming that the PK parameters for each individual within a gender were drawn from the same, biologically varying population, plasma and excretion data were jointly analyzed using a hierarchical framework to separate uncertainty due to measurement error from actual biological variability. Bayesian analysis using Markov Chain Monte Carlo (MCMC) provides tools to perform such an analysis as well as quantitative diagnostics to evaluate and discriminate between models. Starting from a one-compartment PK model with separate clearances to urine and feces, the model was incrementally expanded using Bayesian measures to assess if the expansion was supported by the data. PFOA excretion is sexually dimorphic in rats; male rats have bi-phasic elimination that is roughly 40 times slower than that of the females, which appear to have a single elimination phase. The male and female data were analyzed separately, keeping only the parameters describing the measurement process in common. For male rats, including excretion data initially decreased certainty in the one-compartment parameter estimates compared to an analysis using plasma data only. Allowing a third, unspecified clearance improved agreement and increased certainty when all the data was used, however a significant amount of eliminated PFOA was estimated to be missing from the excretion data. Adding an additional PK compartment reduced the unaccounted-for elimination to amounts comparable to the cage wash. For both sexes, an MCMC estimate of the appropriateness of a model for a given data type, the Deviance Information Criterion, indicated that this two-compartment model was better suited to describing PFOA PK. The median estimate was 142.1 +/- 37.6 ml/kg for the volume of the primary compartment and 1.24 +/- 1.1 ml/kg/h for the clearances of male rats and 166.4 +/- 46.8 ml/kg and 30.3 +/- 13.2 ml/kg/h, respectively for female rats. The estimates for the second compartment differed greatly with gender-volume 311.8 +/- 453.9 ml/kg with clearance 3.2 +/- 6.2 for males and 1400 +/- 2507.5 ml/kg and 4.3 +/- 2.2 ml/kg/h for females. The median estimated clearance was 12 +/- 6% to feces and 85 +/- 7% to urine for male rats and 8 +/- 6% and 77 +/- 9% for female rats. We conclude that the available data may support more models for PFOA PK beyond two-compartments and that the methods employed here will be generally useful for more complicated, including PBPK, models. |
Early functional loading at 5 days for Brånemark implants placed into edentulous mandibles: a prospective, open-ended, longitudinal study.
Traditionally, implants placed in the mandible heal for 3 to 4 months before they are loaded. In maxillae, healing time usually takes 5 to 6 months. The purpose of this study was to evaluate placement of 4 to 6 implants in edentulous mandibles. The implants were placed between mental foramina for support of non-metal, reinforced, fixed, implant-supported provisional prostheses. A unique method was used to convert existing dentures into fixed, implant-supported appliances. The implants were functionally loaded early (5 days). Twenty patients with edentulous mandibles or with 2 to 3 remaining mandibular teeth were enrolled in this open-ended, prospective study. Existing dentures without porcelain teeth were modified for use as a surgical guide. These dentures were used as temporary fixed prostheses. Patients were to have metal-reinforced appliances fabricated by the referring dentists after 3 to 4 months of healing. After implant installation, prosthetic abutments were fixed to the implants and tightened to 20 Ncm without counter torque. Bone quality and quantity as well as implant size and position were entered into a computer database. Impression copings were attached to the abutments, and the modified denture was used for a pick-up impression. After the impression was made, implant replicas were fitted to the impression copings and casts were poured. Gold cylinders were processed into the tissue side of the denture. Laboratory screws were used to attach the denture with gold cylinders to abutment replicas. The dentures were processed, polished, and inserted 5 days after implant surgery. Radiographs were taken to verify proper fit of the gold cylinders to the prosthetic abutments (baseline). Radiographs were taken at each follow-up visit and were used to measure changes in crestal bone levels. Twenty patients received 92 machined-surface commercially pure titanium implants in fully edentulous mandibles. Of the total number of implants placed, two were lost between 0 to 1 year and one between 1 to 2 years. Twenty patients with a total of 90 implants were followed between 0 to 1 year. Fourteen patients have been followed between 1 to 2 years, 7 between 2 to 3 years, and 2 between 3 to 4 years. One patient died after 9 months of loading (4 implants loaded, 2 sleeper implants); another died between 1 to 2 years. A total of 6 implants remained buried (sleepers). At 2 years, the cumulative success rate is 96.3%. Survival of the implant bridges is 100.00%. The mean crestal bone level at 5 days for 11 patients was 2.1 mm (SD 0.526, SE mean 0.159) (measurements were not available for the deceased patient), while the mean level at an average of 15 months was 1.96 mm (SD 0.585, SE mean 0.176). Differences between the measurements taken at 5 days with those taken at an average of 15 months were not significant (P < 0.683). Results of this study indicate that 4 to 5 implants can be placed and loaded within 5 days of implant insertion with high success (96.3%). Success rates for the interim and final prosthesis are 100%. A simple, possibly cost-effective method of using non-metal reinforced dentures as interim fixed, provisional dentures has been described. Impressions and registrations for making the prosthesis can be made at the time of implant installation, and this method is accurate enough to make provisional restorations. The modified denture can function as an interim fixed, implant-supported prosthesis for up to 30 months. Results of x-ray measurements indicate stable crestal bone levels for up to an average of 15 months. |
Deformity and Clinical Outcomes Following Operative Correction of Charcot Foot: A New Classification With Implications for Treatment.
The historic treatment of Charcot foot arthropathy has been immobilization during the active phase of the disease process, followed by accommodative bracing of the acquired deformity. Evidence derived from modern patient-reported outcomes investigations has convinced many surgeons to attempt operative correction of the acquired deformity with a goal of improving quality of life. Over a 12-year period, 214 patients (9 bilateral) underwent reconstruction of the acquired deformity associated with midtarsal Charcot foot arthropathy. Over time, 3 patterns of deformity were observed based on weight-bearing pattern, relationship of the forefoot to the hindfoot, and integrity of the talocalcaneal joint. A valgus deformity pattern was present in 138, varus in 48, and dislocation of the talocalcaneal joint in 37. A consistent operative strategy was employed. Surgery included percutaneous tendon-Achilles lengthening, resection of infection when present, attempted correction of the structural deformity by wedge resection at the apex of the deformity, and immobilization with a 3-level static circular external fixator. Additional deformity pattern-specific procedures were added over time. Clinical outcomes were based on the historic metrics of limb salvage and resolution of infection and the functional metric of the ability to walk with commercially available therapeutic footwear. Seven patients died within a year of surgery, and 15 underwent partial- or whole-foot amputation. Overall, 173 of 223 feet (77.6%) achieved a favorable clinical outcome. Patients with a valgus deformity pattern were most likely to achieve a favorable clinical outcome (120 of 138, 87.0%). Patients with a dislocation pattern were less likely to achieve a favorable clinical outcome (26 of 37, 70.3%), and those with a varus deformity pattern were least likely to achieve a favorable clinical outcome (27 of 48, 56.3%). Operative correction of the acquired deformity of Charcot foot arthropathy was performed with a goal of improving quality of life. Stratification of patients by deformity pattern allowed alterations of the basic surgery to afford improved outcomes. In addition to achieving historic goals of resolution of infection and limb salvage, almost 80% of the patients were able to achieve the functional goal of independent ambulation with commercially available therapeutic footwear. The clinical outcomes achieved in this retrospective case series appear to support the modern paradigm of operative correction of deformity in this complex patient population. This realistic appreciation of outcome expectations should both be helpful in counseling patients on the risk-benefit ratio associated with surgery and provide a benchmark to measure newer strategies of treatment. Level IV, retrospective case series. |
Membrane electrical properties and prediction of motor-unit type of medial gastrocnemius motoneurons in the cat.
Membrane electrical properties [time constant, action potential afterhyperpolarization (AHP), rheobase, input resistance, and axonal conduction velocity] were measured in motoneurons of cat medial gastrocnemius (MG) motor units. Motor units were classified on the basis of their mechanical responses as fast twitch, fast fatiguing (FF); fast twitch with intermediate fatigue resistance (FI); fast twitch, fatigue resistant (FR); or slow twitch, fatigue resistant (S; 11, 22). Motoneuron membrane time constant, estimated from the voltage response at the onset or termination of long (50-100 ms) current pulses and corrected for voltage-response nonlinearities (32), was found to differ significantly among the major motor-unit types, increasing in the order FF less than FR less than S. Afterhyperpolarization magnitude, half-decay time, and duration were all significantly greater for the fast (FF + FI + FR) versus the slow (S) motor units. The AHP half-decay time was correlated with muscle unit twitch time over the entire motoneuron population and within the type S motor-unit population. There was no significant correlation between twitch time and AHP half-decay time among the types FF and FR motor-unit populations. In agreement with previous studies, we found a significant difference in both rheobase and input resistance among the major motor-unit types, with rheobase increasing in the order S less than FR less than FF and input resistance decreasing in that order (S greater than FR greater than FF). The differences in input resistance were present both before and after correcting for voltage-response nonlinearities (32). Also in agreement with previous studies, the mean axonal conduction velocity was significantly faster among the fast (FF + FI + and FR) compared with the slow (S) motor units. These data were used to examine the properties alone to determine motor-unit type, which has traditionally been defined on the basis of the muscle unit's mechanical properties (11, 22). We used a discriminant analysis program to classify 73 mechanically typed motor units for which we had measures of rheobase, input resistance, membrane time constant, and AHP half-decay time. This model was able to properly classify 71 of the 73 motor units of this data set, indicating that the motor units of this data set could be grouped into three categories representing the three major motor-unit types (FF, FR, and S) on the basis of their rheobase, input resistance, membrane time constant, and AHP half-decay time.(ABSTRACT TRUNCATED AT 400 WORDS) |
Transfusion of fresher versus older red blood cells for all conditions.
Red blood cell transfusion is a common treatment for anaemia in many clinical conditions. One current concern is uncertainty as to the clinical consequences (notably efficacy and safety) of transfusing red blood cell units that have been stored for different durations of time before a transfusion. If evidence from randomised controlled trials were to indicate that clinical outcomes are affected by storage age, the implications for inventory management and clinical practice would be significant. To assess the effects of using fresher versus older red blood cells in people requiring a red blood cell transfusion. We ran the search on 29th September 2014. We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE (OvidSP), Embase (OvidSP), CINAHL (EBSCO), PubMed (for e-publications), three other databases and trial registers. We included randomised controlled trials comparing fresher red blood cell transfusion versus active transfusion of older red blood cells, and comparing fresher red blood cell transfusion versus current standard practice. All definitions of 'fresher' and 'older'/'standard practice' red blood cells were included. Two review authors independently assessed trial quality and extracted from the trial report data on adverse red blood cell transfusion reactions, when reported. We included 16 trials (1864 participants) in the review. Eight trials (279 participants) compared transfusion of fresher red blood cells versus transfusion of older stored red blood cells ('fresher' vs 'older'). Eight trials (1585 participants) compared the transfusion of fresher red blood cells versus current standard practice ('fresher' vs 'standard practice'). Five trials enrolled neonates, one trial enrolled children and 12 trials enrolled adults. Overall sample sizes were small: only two trials randomly assigned more than 100 participants.We performed no meta-analyses for a variety of reasons: no uniform definition of 'fresher' or 'older' red blood cell storage; overlap in the distribution of the age of red blood cells; and heterogeneity in measurements and reporting of outcomes of interest to this review. We tabulated and reported results by individual trial. Overall risk of bias was low or unclear, with four incidences of high risk of bias: in allocation concealment (three trials) and in incomplete outcome data (one trial).No trial measured all of the outcomes of interest in this review. Four trials comparing 'fresher' with 'older' red blood cells reported the primary outcome: mortality within seven days (one study; 74 participants) and at 30 days (three trials; 62 participants). Six trials comparing 'fresher' with 'standard practice' red blood cells reported the primary outcome: mortality within seven days (three studies; 159 participants) and at 30 days (three trials; 1018 participants). All 10 trials reported no clear differences in mortality at either time point between intervention arms.Three trials comparing 'fresher' with 'standard practice' red blood cells reported red blood cell transfusion-associated adverse events. No adverse reactions were reported in two trials, and one incidence of cytomegalovirus (CMV) infection was described in the 'standard practice' arm in one trial.Overall the trials reported no clear difference between either of the intervention comparisons in long-term mortality (three trials; 478 participants); clinically accepted measures of multiple organ dysfunction (two trials: 399 participants); incidence of in-hospital infection (two trials; 429 participants); duration of mechanical ventilation (three trials: 95 participants); and number of participants requiring respiratory organ support (five trials; 528 participants) or renal support (one trial; 57 participants). The outcome 'physiological markers of oxygen consumption or alterations in microcirculation' was reported by 11 studies, but the measures used were highly varied, and no formal statistical analysis was undertaken. Several factors precluded firm conclusions about the clinical outcomes of transfusing red blood cell units that have been stored for different periods of time before transfusion, including differences in clinical population and setting, diversity in the interventions used, methodological limitations and differences in how outcomes were measured and reported.No clear differences in the primary outcome - death - were noted between 'fresher' and 'older' or 'standard practice' red blood cells in trials that reported this outcome. Findings of a large number of ongoing trials will be incorporated into this review when they are published.Updates of this review will explore the degree of overlap in trials between 'fresher', 'older' and 'standard practice' storage ages of red blood cells and will consider whether the size of any observed effects is dependent on recipient factors such as clinical background, patient age or clinical presentation. |
Atypical adenomatous hyperplasia of the prostate. Relationship with carcinoma in 217 whole-mount radical prostatectomies.
Atypical adenomatous hyperplasia (AAH) of the prostate is a microscopic proliferation of small glands that may be mistaken for adenocarcinoma. The extent and multicentricity of this histopathologic lesion have not been fully defined, and the spatial relationship with carcinoma has not been described in whole-mount surgical specimens. We sought to determine whether the extent and zonal location of AAH is related to prostate cancer by evaluating 217 totally embedded radical prostatectomy specimens with cancer. All but 17 patients had clinically localized cancer, and none had received preoperative therapy. The number of foci and volume of AAH were measured using a grid-counting method; proximity to cancer was recorded as either less than or equal to 2 mm from cancer or greater than 2 mm from cancer. AAH was identified in 23.0% of cases and was more frequent in the transition zone (19.8% of cases) than in the nontransition (peripheral and central) zone (6.0%). It was found within 2 mm of cancer in 34% of cases of AAH, including 30% of cases in the transition zone and 31% cases in the nontrasition zone. The number of foci of AAH in the transition zone was always greater than that in the nontransition zone, regardless of whether it was within 2 mm of cancer or more than 2 mm from cancer. AAH was frequently multicentric (46% of cases), especially in the transition zone (47% of transition zone cases) compared with the nontransition zone (23% of nontransition zone cases). The mean volume of AAH was 0.029 cc (range, 0-1.29 cc) and was much higher in the transition zone than the nontransition zone, regardless of whether it was within 2 mm of cancer or more than 2 mm from cancer. In cases of AAH within 2 mm of cancer, the volume was lower than in cases more than 2 mm from cancer; this was true regardless of zonal location. AAH was more common in older patients and in those with greater prostatic weight, higher prostatic volume, greater percentage of nodular hyperplasia, greater volume of cancer, greater percent of Gleason patterns 4 and 5 cancer, higher volume of prostatic intraepithelial neoplasia, and higher serum prostate-specific antigen level. There was no correlation of number of foci of AAH or volume of AAH with pathologic stage, seminal vesicle invasion, Gleason primary pattern or score, nuclear grade, perineural invasion by tumor, or DNA ploidy. Our results indicate that AAH is usually found iin the transition zone in association with nodular hyperplasia and is often multicentric. The extent and zonal distribution of AAH and carcinoma show a weak but significant association. |
Spotlight on rizatriptan in migraine.
Rizatriptan is an orally active serotonin 5-HT(1) receptor agonist that potently and selectively binds to 5-HT(1B/1D) subtypes. Earlier clinical trials demonstrated that rizatriptan 5 or 10mg is more effective than placebo at providing pain relief and a pain-free state, relieving associated symptoms of migraine, normalising functional ability and improving patient quality of life, and showed that rizatriptan provides faster freedom from pain and reduces nausea to a greater extent than oral sumatriptan. More recently, rizatriptan 10mg was shown to be more effective than zolmitriptan 2.5mg or naratriptan 2.5mg at producing a pain-free state 2 hours postdose. Furthermore, compared with naratriptan, significantly more patients who received rizatriptan were pain free or had pain relief from 1 hour onwards. The number of patients with normal functional ability at 2 hours was significantly higher after rizatriptan than after naratriptan or zolmitriptan. Rizatriptan was also generally more effective than zolmitriptan or naratriptan at relieving migraine-associated symptoms. Rizatriptan is generally well tolerated, and adverse events are usually mild and transient. The most common adverse events associated with rizatriptan in recent randomised trials were asthenia/fatigue, dizziness, somnolence and nausea. There was a trend towards a lower incidence of adverse events with rizatriptan compared with zolmitriptan (31.2 vs 38.8%). However, rizatriptan was associated with a significantly higher incidence of adverse events than naratriptan (39 vs 29%). The incidence of chest pain was similar after the administration of rizatriptan, zolmitriptan or naratriptan (2-4%). In conclusion, rizatriptan is an effective drug for the acute treatment of moderate or severe migraine. Oral rizatriptan 5 and 10mg have shown greater efficacy than placebo in providing pain relief, an absence of pain, relief from associated symptoms, normal functional ability and an improvement in patient quality of life. Earlier results showed that rizatriptan provides faster freedom from pain and reduces nausea to a greater extent than oral sumatriptan. More recent studies have shown that rizatriptan 10mg provides faster pain relief and a higher percentage of patients with an absence of pain and normal functional ability at 2 hours than naratriptan 2.5mg or zolmitriptan 2.5mg. The efficacy of rizatriptan is retained when used in the long term, and the drug is generally well tolerated. Although well designed studies comparing rizatriptan with almotriptan, eletriptan and frovatriptan would further define the position of rizatriptan, current data suggest that rizatriptan should be considered as a first-line treatment option in the management of migraine. |
Invasive urodynamic studies for the management of lower urinary tract symptoms (LUTS) in men with voiding dysfunction.
Invasive urodynamic tests are used to investigate men with lower urinary tract symptoms (LUTS) and voiding dysfunction to determine a definitive objective diagnosis. The aim is to help clinicians select the treatment that is most likely to be successful. These investigations are invasive and time-consuming. To determine whether performing invasive urodynamic investigation, as opposed to other methods of diagnosis such as non-invasive urodynamics or clinical history and examination alone, reduces the number of men with continuing symptoms of voiding dysfunction. This goal will be achieved by critically appraising and summarising current evidence from randomised controlled trials related to clinical outcomes and cost-effectiveness. This review is not intended to consider whether urodynamic tests are reliable for making clinical diagnoses, nor whether one type of urodynamic test is better than another for this purpose.The following comparisons were made.• Urodynamics versus clinical management.• One type of urodynamics versus another. We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (2014, issue 10), MEDLINE (1 January 1946 to Week 4 October 2014), MEDLINE In-Process and other non-indexed citations (covering 27 November 2014; all searched on 28 November 2014), EMBASE Classic and EMBASE (1 January 2010 to Week 47 2014, searched on 28 November 2014), ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform (WHO ICTRP) (searched on 1 December 2014 and 3 December 2014, respectively), as well as the reference lists of relevant articles. Randomised and quasi-randomised trials comparing clinical outcomes in men who were and were not investigated with the use of invasive urodynamics, or comparing one type of urodynamics against another, were included. Trials were excluded if they did not report clinical outcomes. Three review authors independently assessed trial quality and extracted data. We included two trials, but data were available for only 339 men in one trial, of whom 188 underwent invasive urodynamic studies. We found evidence of risk of bias, such as lack of outcome information for 24 men in one arm of the trial.Statistically significant evidence suggests that the tests did change clinical decision making. Men in the invasive urodynamics arm were more likely to have their management changed than men in the control arm (proportion with change in management 24/188 (13%) vs 0/151 (0%), risk ratio (RR) 39.41, 95% confidence interval (CI) 2.42 to 642.74). However, the quality of the evidence was low.Low-quality evidence indicates that men in the invasive urodynamics group were less likely to undergo surgery as treatment for voiding LUTS (164/188 (87%) vs 151/151 (100%), RR 0.87, 95% CI 0.83 to 0.92).Investigators observed no difference in urine flow rates before and after surgery for LUTS (mean percentage increase in urine flow rate, 140% in invasive urodynamic group vs 149% in immediate surgery group, P value = 0.13). Similarly, they found no differences between groups with regards to International Prostate Symptom Score (IPSS) (mean percentage decrease in IPSS score, 58% in invasive urodynamics group vs 59% in immediate surgery group, P value = 0.22).No evidence was available to demonstrate whether differences in management equated to improved health outcomes, such as relief of symptoms of voiding dysfunction or improved quality of life.No evidence from randomised trials revealed the adverse effects associated with invasive urodynamic studies. Although invasive urodynamic testing did change clinical decision making, we found no evidence to demonstrate whether this led to reduced symptoms of voiding dysfunction after treatment. Larger definitive trials of better quality are needed, in which men are randomly allocated to management based on invasive urodynamic findings or to management based on findings obtained by other diagnostic means. This research will show whether performance of invasive urodynamics results in reduced symptoms of voiding dysfunction after treatment. |
A randomized phase III study of accelerated hyperfractionation versus standard in patients with unresected brain metastases: a report of the Radiation Therapy Oncology Group (RTOG) 9104.
To compare 1-year survival and acute toxicity rates between an accelerated hyperfractionated (AH) radiotherapy (1.6 Gy b.i.d.) to a total dose of 54.4 Gy vs. an accelerated fractionation (AF) of 30 Gy in 10 daily fractions in patients with unresected brain metastasis. The Radiation Therapy Oncology Group (RTOG) accrued 445 patients to a Phase III comparison of accelerated hyperfractionation vs. standard fractionation from 1991 through 1995. All patients had histologic proof of malignancy at the primary site. Brain metastasis were measurable by CT or MRI scan and all patients had a Karnofsky performance score (KPS) of at least 70 and a neurologic function classification of 1 or 2. For AH, 32 Gy in 20 fractions over 10 treatment days (1.6 Gy twice daily) was delivered to the whole brain. A boost of 22.4 Gy in 14 fractions was delivered to each lesion with a 2-cm margin. The average age in both groups was 60 years; nearly two-thirds of all patients had lung primaries. Of the 429 eligible and analyzable patients, the median survival time was 4.5 months in both arms. The 1-year survival rate was 19% in the AF arm vs. 16% in the AH arm. No difference in median or 1-year survival was observed among patients with solitary metastasis between treatment arms. Recursive partitioning analysis (RPA) classes have previously been identified and patients with a KPS of 70 or more, a controlled primary tumor, less than 65 years of age, and brain metastases only (RPA class I), had a 1-year survival of 35% in the AF arm vs. 25% in the AH arm (p = 0.95). In a multivariate model, only age, KPS, extent of metastatic disease (intracranial metastases only vs. intra- and extracranial metastases), and status of primary (controlled vs. uncontrolled) were statistically significant (at p < 0.05). Treatment assignment was not statistically significant. Overall Grade III or IV toxicity was equivalent in both arms, and one fatal toxicity at 44 days secondary to cerebral edema was seen in the AH arm. Although a previous RTOG Phase I/II report had suggested a potential benefit in patients with limited metastatic disease, a good Karnofsky performance status, or neurologic function when treated with an AH regimen, this randomized comparison could not demonstrate any improvement in survival when compared to a conventional regimen of 30 Gy in 10 fractions. Therefore, this accelerated hyperfractionated regimen to 54.4 Gy cannot be recommended for patients with intracranial metastatic disease. |
ReQuest-- the challenge of quantifying both esophageal and extra-esophageal manifestations of GERD.
Gastroesophageal reflux disease (GERD) is highly prevalent in Western countries. It is characterized by esophageal and extra-esophageal symptoms (both typical and atypical) as well as by a number of potential complications. As the majority of patients have normal gross endoscopic findings, the assessments of symptom severity and quality of life, as well as the patients' response to treatment have become increasingly important. Self-assessed symptom questionnaires are now key instruments in clinical trials. An ideal GERD symptom questionnaire, suitable as a primary end-point for clinical trials, should: (1) be sensitive in patients with GERD, (2) cover frequency and intensity of typical and atypical GERD symptoms, (3) be multidimensional (cover all symptom dimensions), (4) have proven psychometric properties (validity, reliability and responsiveness), (5) be practical and economical, (6) be self-assessed, (7) use 'word pictures' which are easy to understand for patients, (8) respond rapidly to changes (responsiveness in short-time intervals), (9) be used daily to assess changes during and after therapy, and (10) be valid in different languages for international use. A literature review revealed five evaluative scales that met some of the above characteristics, but none fulfilled all of them. Therefore, a new evaluative tool for the assessment of GERD symptoms and their response to therapy is needed. The Reflux Questionnaire (ReQuest) is a self-assessed questionnaire developed and validated to assess the effect of treatment on the spectrum of GERD-related symptoms. Initially, GERD symptoms were identified on the basis of available literature, knowledge from previous clinical trials, experienced physicians, and patient interviews. An overall of 67 typical and atypical symptom descriptions were grouped into six different dimensions of GERD (acid complaints, upper abdominal/stomach complaints, lower abdominal/digestive complaints, nausea, sleep disturbances, other complaints). To these six dimensions a seventh, general well-being was added. Each dimension was tested by questions for frequency and intensity (except general well-being, for which only the intensity was determined). Thereafter, ReQuest was translated into different languages and tested in mother tongue patient focus groups. ReQuest psychometric properties (test-retest reliability, internal consistency, construct validity, responsiveness) were validated in two clinical trials of erosive GERD and endoscopic negative (en) GERD. In the first open, multicenter study, ReQuest was assessed in 430 patients with erosive GERD grade A-D. Patients with GERD grade A were treated with pantoprazole 20 mg od whereas those with GERD grade B-D received 40 mg od. The second open, multicenter, multinational trial with pantoprazole 20mg od assessed the ReQuest in over 800 patients with endoscopic negative GERD. Furthermore, ReQuest was used to determine the 'normal' ranges of GERD symptoms in individuals without GERD evidence. Over 300 healthy volunteers took part in a 4-day evaluation by completing ReQuest on each of the four study-days, as well as GSRS and PGWB on day 1. Based on the 90% percentiles determined in this study, a 'normal' range was calculated for ReQuest and relative subscales. The study showed that even individuals without GERD evidence can experience mild GERD symptoms. The derived 'normal' ranges within the population can be used for classification of symptom relief. In conclusion, ReQuest proved to be a valid, reliable, and responsive tool for measuring both typical and atypical GERD symptoms, and to be particularly suitable for measuring daily symptom changes and identifying normalization of the clinical picture in therapeutic trials. |
First Report of Stemphylium globuliferum Causing Stemphylium Leaf Spot on Alfalfa (Medicago sativa) in the United States.
Stemphylium leaf spot occurs in most areas where alfalfa (Medicago sativa) is grown. In the United States, Stemphylium botryosum is reported to be the predominant pathogen (1), although S. vesicarium and S. herbarum are also observed. S. alfalfae was isolated on alfalfa in Australia (4) and S. globuliferum was reported in Egypt and Korea. In April and May 2012, alfalfa plants with leaf spot symptoms were observed in Rosemount and Waseca, MN, and in Arlington, Tomah, and Waupaca, WI. Initial symptoms consisted of white to tan spots with a brown border, 2 to 3 mm in diameter, circular to oval, enlarging to 5 to 8 mm in diameter. Large lesions often coalesced. Small, narrow, brown lesions occurred on petioles. Lower killed leaves remained attached to the primary stem. Spots were larger than those caused by the cool temperature biotype of S. botryosum. Conidia formed on lesions after 48 h in a moist chamber. Conidia were removed with a fine glass rod, germinated on 1% water agar, and single hyphae transferred to V8 agar (V8A). After 2 weeks under room light, plates were placed under UV light to stimulate spore production. Conidia on host material were borne singly on straight, unbranched, smooth conidiophores, medium brown at the apex. Conidia were medium to dark brown with small papillae, subspherical with 3 to 4 transverse and 3 to 4 complete or near complete longitudinal septa, with a distinct constriction at the median transverse septum. Conidia were 27.5 to 32.5 μm long × 20 to 22.5 μm wide with a length/width (L/W) ratio of 1.2 to 1.5. Conidia on V8A were smaller, 25 to 30 μm long × 12.5 to 19 μm wide with a L/W of 1.6 to 1.8. Ascostromata 300 μm in diameter formed on leaves held at 4°C for 2 months as well as on culture plates after 1 month. Ascospores from leaves were golden brown to reddish, 40 to 42.5 × 20 μm, slightly broader in the upper half of the spore, with 7 to 8 transverse septa and one complete longitudinal septum with several incomplete septa. Ascospores from culture were smaller, 27.5 to 30 × 12.5 to 15 μm wide. These morphological features are consistent with the description for S. globuliferum (3). DNA was extracted from pure cultures of SAr301 and SWp202, isolated from plants grown in Arlington and Waupaca, respectively, and used to amplify ITS1-5.8S-ITS2 rDNA using primers ITS1 and ITS4, GPD with primers GPD1 and GPD2, EF-1α with EF446f and EF1473R, and the intergenic spacer between vmaA and vpsA with primers ATPF2 and GTP604R (2). In sequence comparisons made by BLASTn searches of GenBank, the ITS (KF479193), GPD (KF479194), and EF-1α (KF479195) sequences from S. globuliferum were different from the gene sequences of S. botryosum but identical to those from S. vesicarium, S. herbarum, and S. alfalfae. The vmaA-vpsA spacer sequence (KF479196) of S. globuliferum had 3 nucleotide differences from S. vesicarium and S. herbarum and 4 nucleotide differences from S. alfalfae, demonstrating that this sequence is useful for species discrimination. Conidia from strains SAr301 and SWp 202 were suspended at 104/ml in sterile water with 0.01% Tween 20 and used to inoculate 12 alfalfa plants using a handheld sprayer. Plants were kept at 100% RH for 48 h, then grown at 20°C with a 16-h photoperiod. After 2 weeks, lesions similar to those seen in the field were observed on leaves of all plants. Symptomatic leaves placed in moist chambers produced conidia with the size and morphology of S. globuliferum within 48 h. This is the first report to our knowledge of S. globuliferum causing disease on alfalfa in the United States. Cultures were deposited in the University of Minnesota Mycological Culture Collection. References: (1) W. A. Cowling et al. Phytopathology 71:679, 1981. (2) P. Inderbitzin et al. Mycologia 101:320, 2009. (3) E. G. Simmons. Mycologia 61:1, 1969. (4) E. G. Simmons. Sydowia 38:284, 1985. |
Cisapride decreases gastroesophageal reflux in preterm infants.
Gastrointestinal prokinetic agents, such as cisapride, are commonly used in pediatric practice to improve gastric emptying, to decrease emesis, to improve lower esophageal sphincter tone, and to improve irritability and feeding aversion associated with gastroesophageal reflux (GER). Although cisapride seems to be effective in infants from 2 months to 14 years old, data for younger and preterm infants are not available. Whether reflux is a significant cause of reflex apnea or feeding intolerance in the preterm infant is controversial. The objective of this 1-year prospective study, started in 1998, was to determine the efficacy of cisapride for treatment of reflux and reflux-associated apnea (RAAP) in preterm infants. Before this study, the diagnosis of reflux was often made clinically and the effect of therapy on reflux or the decision to increase the dose of cisapride was made empirically. The clinical bias was that persistent apnea, not responding to caffeine, was caused by GER. We reasoned that a systematic approach to the diagnosis and treatment of reflux would improve the care of preterm infants and reduce the risk of toxicity, especially if an increased dose of cisapride showed no improvement in reflux or apnea. Twenty-four preterm infants (24-36 weeks' gestational age) had clinical apnea/pH studies when they were referred by the attending neonatologist for suspected GER. These infants were born at 28.8 +/- 3.1 weeks with birth weight of 1169 +/- 387 g (range: 631-2263 g). Each infant was studied before and 8 days after starting cisapride treatment. Cisapride dose was 0.09 to 0.25 mg/kg every 6 hours enterally. Treatment decisions regarding dose of cisapride were the responsibility of the attending neonatologist. The pH was recorded continuously for 24 hours at 0.25 Hz and was analyzed using EsopHogram software. A single sensor pH catheter was inserted to ~2 cm above the esophageal gastric junction. GER was defined as a drop in esophageal pH below 4.0 for a least 5 seconds, or pathologic GER was defined as a reflux index (RI) >2 standard deviation (SD) from the mean based on published norms for term infants. The following parameters were calculated from the pH recording: number of reflux events per 24 hours, duration of the longest episode, number of episodes >5 minutes per 24 hours, and RI, ie, percentage of time with pH <4.0. Each study had a combined time-lapse video recording and multichannel digital recording. Recorded parameters were: continuous pulse oximetry, electrocardiogram, respiratory effort (piezo sensor), and airflow (temperature sensor at nostrils and mouth). The recording was scored for central apneas of 10 to 14 seconds and >/=15 seconds (prolonged) and >/=10 seconds for obstructive and mixed apneas. RAAP was scored when an apnea (irrespective of the type) occurred within 1 minute of a GER event. Baseline, after cisapride, and follow-up electrocardiograms were performed because of concern about prolonged QTc and cardiac arrhythmias. The infants were 35.6 +/- 4.5 weeks postconceptional age when first studied. Twelve infants (mean birth weight: 1821 +/- 749 g; gestational age: 32 +/- 2 weeks; postconceptional age: 35.6 +/- 2.6 weeks) were identified retrospectively as controls because their baseline GER parameters were within the normal range using Vandenplas' criteria. Overall, cisapride treatment significantly improved the RI from 16.6 +/- 15.2 to 9.1 +/- 8.4 SD. The number of reflux episodes >/=5 minutes was reduced from 7.1 +/- 5.8 to 4.3 +/- 4.4 SD. No significant effect was seen on the total number of refluxes (/24 hours). Eight infants (33%) had no decrease in the RI after a week of treatment. Three of these infants improved after cisapride dose was increased from 0.09 to 0.25 mg/kg/dose every 6 hours. Although 0.09 mg/kg/day is the minimum effective dose, 67% of our infants did respond to this low dose. Cisapride was discontinued in 3 infants because of prolonged QTc >/=0.450 seconds (0.473 in 1 and 0.470 in 2). More data about the effect of cisapride on QTc interval are reported in Pediatrics in a separate article. Only 1 infant showed no improvement with increased dose. Caffeine treatment had no effect on the baseline or follow-up GER values. Although apnea indexes for central and obstructive apnea were similar before and after cisapride, mixed apnea was less during treatment. There was a significant decrease (0.32 +/- 0.40 to 0.12 +/- 0.17/hour) in RAAP when the one infant who had increased reflux on increased dose of cisapride was excluded as an outlier. The statistical difference, before and after cisapride, for the group is significant with the outlier omitted. The clinical significance is unclear because ~50% of the infants had minimal changes in their apnea indexes. Furthermore, ~40% of infants did not have RAAP. (ABSTRACT TRUNCATED) |
Continued multicenter followup of cadaveric prolapse repair with sling.
Since our initial description of the technique of combining a transvaginal sling with a cystocele repair using solvent dehydrated cadaveric fascia lata and bone anchors we have continued to follow our outcomes closely to determine long-term results. We present the updated, multicenter results of the cadaveric prolapse repair with sling. A total of 172 patients 35 to 90 years old (mean age 62.1) have undergone cadaveric prolapse repair with sling with a mean followup of 12.4 months (range 6 to 28). Of these patients 132 (76.7%) completed followup. Repair was performed for grade 2 cystoceles in 73 cases, grade 3 cystoceles in 43 and grade 4 cystoceles in 16. Followup included physical examination (degree of pelvic prolapse), SEAPI scores, complications, patient reported continence, perceived improvement and satisfaction. The latter 2 parameters were obtained using a validated questionnaire. Of the 132 patients 15 (11.4%) had grade 1 and 2 (1.5%) had grade 2 cystocele recurrence, which required no further treatment, and 13 (9.8%) had recurrent or de novo apical vaginal prolapse. Preoperative and postoperative SEAPI scores were 5.58 and 0.9, respectively (p <0.001). A total of 90 patients (68.2%) do not use any pads for protection. Of the 132 patients 24 (18.2%) have stress incontinence of any degree, including 14 (10.6%) with pure stress urinary incontinence, 8 (6.0%) report de novo urge incontinence, 26 (19.7%) have persistent urge incontinence, 21 (15.9%) have any degree of urgency without urge incontinence, 28 (21.2%) report resolution of preoperative urgency or urge incontinence symptoms, 7 (5.3%) have mixed incontinence and 1 had prolonged urinary retention requiring urethrolysis. There has been 1 case of osteitis pubis and no osteomyelitis. Of the patients 94 (71.2%) reported greater than or equal to 70% subjective improvement overall, including 12 who were dry preoperatively, 99 (75.0%) were greater than or equal to 70% satisfied, 105 (79.9%) would repeat the surgery and 102 (77.4%) would recommend the surgery to a friend. With regard to continence 31 (23.8%) patients were less than or equal to 50% improved. A total of 108 (81.8%) patients have no stress urinary incontinence, and patient improvement, satisfaction and complication rates have been acceptable. We have been particularly impressed by the results of the cystocele repair. Surgeons must consider that patient perceived improvement and satisfaction level are essential components of the measure of success or failure of a given therapy. With a maximum of 28 months of followup of the cadaveric prolapse repair with sling procedure, we continue to be satisfied with the success of the cystocele repair and the competitive stress urinary incontinence cure rate. |
Pharmaco-EEG and psychometric studies with a novel selective benzodiazepine agonist/antagonist Ro 23-0364.
In a double-blind, placebo-controlled study, the encephalotropic and psychotropic properties of Ro 23-0364, a novel imidazobenzodiazepine with mixed benzodiazepine agonist/antagonist properties, were investigated as compared with the pure agonist diazepam utilizing quantitative EEG and psychometric analyses as well as clinical observations. Ten normal volunteers received randomized (latin square) and at weekly intervals single oral doses of placebo, 0.25 mg, 0.5 mg and 1.0 mg Ro 23-0364 and 10 mg diazepam as reference drug. EEG-recordings and evaluation of pulse, blood pressure and side effects were carried out at the hours 0, 1, 2, 4, 6, and 8; psychometric tests at the same times except the first hour. Computer-assisted spectral analyses of the EEG demonstrated after 10 mg diazepam a typical "anxiolytic" pharmaco-EEG profile characterized by an increase of beta-activity, decrease of alpha-activity and absolute and relative power of the dominant frequency, furthered by an acceleration of the centroid of the total activity and a slowing of the centroid of the combined delta/theta-activity. In addition, there was an increase of delta-activity specifically in the resting recording condition suggesting also sedative properties of the reference compound. Ro 23-0364 induced in the vigilance-controlled recordings a similar profile as diazepam-although less pronounced-thereby exhibiting tranquilizing qualities. However, in the resting condition the most consistent change was an augmentation of delta/theta-activity along with an attenuation of alpha-activity, which was evident already in the lower dosage range and is reminiscent also of changes seen after sedative neuroleptic drugs (although the centroid slowing was missing). These data indicate a selective sedation of the mixed agonist/antagonist in the resting state. Dose-efficacy calculations based on EEG-changes demonstrated the reference compound, 1.0 and 0.5 mg Ro 23-0364 different from placebo. 10 mg diazepam was by far the most CNS-active compound inducing significantly more changes than the three doses of the mixed agonist/antagonist. Within the latter the two higher doses were superior to 0.25 mg but could not be differentiated from each other. Time-efficacy calculations showed the maximal encephalotropic effect of diazepam within the first two hours while the peak effect of 1.0 mg and 0.5 mg Ro 23-0364 fell into the 6th and 4th hour, respectively. There were no differences between the time periods after 0.25 mg although there was a trend towards high activity in the first two hours followed by a trough in the 4th and 6th hour and thereafter again an increase.(ABSTRACT TRUNCATED AT 400 WORDS) |
Randomized phase II noncomparative trial of oral and intravenous doxifluridine plus levo-leucovorin in untreated patients with advanced colorectal carcinoma.
Doxifluridine (5-dFUR) is a fluoropyrimidine derivative that has been shown to be active on a variety of solid tumors. The clinical use of intravenous (i.v.) 5-dFUR as a bolus injection or short term infusion has been limited because of its unpredictable severe neurotoxicity. Unlike fluorouracil (5-FU), 5-dFUR is effective when administered orally. This randomized, parallel-group, Phase II trial of two schedules of 5-dFUR was conducted between April 1993 and September 1994. A total of 130 previously untreated patients with locally advanced or metastatic colorectal carcinoma were randomized to receive oral levo-leucovorin (1-leucovorin) 25 mg/dose followed by oral 5-dFUR 750 mg/m2 twice daily for 4 days every 12 days (arm A) or i.v. 1-leucovorin 25 mg/dose followed by i.v. 5-dFUR 3000 mg/m2 for 5 days every 21 days (arm B). The two treatment arms were well balanced in terms of age, sex, and disease extension. Metastases were present in more than 90% of the total population, with the liver being the most common site. A median of 7 oral courses (range, 1-15) and 5 intravenous courses (range, 1-9) were administered. Intent-to-treat analysis rate of the randomized patients revealed a response rate of 15% (95% confidence interval [CI], 7-26) in arm A and 41% (95% CI, 29-54) in arm B. However, 7 cases in arm A and 12 in arm B were inadequately treated, and the response rates, according to standard analysis, were respectively 17% (95% CI, 8-28) and 51% (95% CI, 37-65). The median time to treatment failure was 4 months (range, 1-23) and 7 months (range, 1-9), respectively, for the two groups; median survival was 11 months (range, 1-24) in both groups. National Cancer Institute Grade 3 and 4 diarrhea were observed in 25% of the orally treated patients and in 18% of those receiving i.v. treatment. Stomatitis was reported mainly in arm B (15%). Mild and moderate neurotoxicity was observed in 6% of the patients in both arms; no severe neurotoxicity was reported. 5-dFUR with l-leucovorin, administered either orally or intravenously, produces response rates that are similar to those offered by the regimens containing 5-FU that are usually used to treat advanced colorectal carcinoma. This study documents the good tolerance of the i.v. schedule administered as a 1-hour infusion; furthermore, oral administration seems to be promising and feasible as a home treatment. |
Cost analysis comparing brachytherapy versus surgery for primary carcinoma of the tonsillar fossa and/or soft palate.
Locoregional control rates, late normal tissue sequelae, and functional outcome scores have not been different for tonsillar fossa and/or soft palate tumors treated by either brachytherapy (BT) or surgery in an organ function preservation protocol. For additional prioritizing in clinical decision-making, we focused on a comparison of the full hospital costs of the different treatment options. Between 1986 and 2001, tonsillar fossa and/or soft palate tumors were treated by external beam radiotherapy (EBRT) to the primary tumor and neck, followed by fractionated BT to the primary. Neck dissection (ND) was performed for node-positive disease (BT group; 104 patients). If BT was not feasible, resection combined with postoperative EBRT was executed (surgery group; 86 patients). Locoregional control, disease-free survival, and overall survival were calculated according to the Kaplan-Meier method. The performance status scales, late side effects, and degree of xerostomia have been previously reported. This paper focused on the hospital and follow-up costs for the treatment groups EBRT and BT with or without ND compared with surgery followed by postoperative RT (PORT). Finally, these costs were also computed for future treatment strategies (e.g., better sparing of normal tissues by intensity-modulated RT [IMRT]). Locoregional control, disease-free survival, and overall survival rate at 5 years for patients treated with EBRT and BT with or without ND vs. surgery plus PORT was 80% vs. 78%, 58% vs. 55%, and 67% vs. 57%, respectively. The major late side effect was xerostomia. Dry mouth syndrome affected the BT group and surgery group equally. The total costs for all treatment groups were 14,262 euro (BT group), 16,628 euro (BT plus ND group), 18,782 euro (surgery plus PORT group), 14,532 euro (IMRT group), and 16,897 euro (IMRT plus ND group). Excellent locoregional tumor control was observed with either modality, with no statistically significant differences in the incidence of the most noted side effect xerostomia. The total costs for BT were less than for surgery: 16,628 euro (19,452 dollars) for EBRT plus BT plus ND vs. 18,782 euro(22,074 dollars) for surgery plus PORT. To reduce the morbidity of xerostomia, we propose further optimizing our organ function preservation protocol by implementing IMRT as a more conformal, tissue-sparing, RT technique. This is of particular interest because the costs of IMRT plus ND (16,897 euro; 19,767 dollars) were not very different from those for BT plus ND (16,628 euro; 19,452 dollars) and were far less than the costs for surgery. |
Toward the identification of mesenchymal stem cells in bone marrow and peripheral blood for bone regeneration.
The advent of monoclonal antibody stem cell marker technology has made it possible to identify a variety of human stem cells and their progeny. Specific markers exist for cells related to bone healing and bone regeneration. These include but are not limited to hematopoietic, mesenchymal, endothelial, angiogenic, and vasculargenic precursor cells. The purpose of this investigation was to (1) to identify, by means of cell markers, the presence of stem cells needed for bone formation within peripheral blood and bone-marrow aspirate, and (2) to ascertain whether more of those stem cells were present in the bone-marrow aspirate than the peripheral blood. Samples of autogenous bone-marrow aspirate and peripheral blood from 6 patients ranging in age from 23 to 73 were analyzed with 6-column flow cytometry using cell markers for stem cells relating to bone growth and bone healing. Six monoclonal antibody cell markers were utilized: CD14, CD34, CD36, CD105, CD106, and CD309 (also known as vascular endothelial growth factor receptor or KDR). Subgroups reacting to these markers or combinations of markers were then further tested with other marker combinations. : The expression of specific monoclonal antibody cell markers revealed that bone marrow contained more osteogenic stem cells than peripheral blood. Bone marrow contained a higher percentage of cells that reacted with the CD34 and CD14 markers. This suggests that bone marrow contains more hematopoietic stem cells that proliferate to become myeloid progenitor cells, megakaryocytes, monocyte/macrophages, and osteoclast progenitors. When the fractions of bone marrow and peripheral blood samples that reacted with both CD34 and CD14 were further tested for CD105, more of the fraction from bone marrow reacted to CD105 than that from peripheral blood, suggesting more osteogenic potential in the bone marrow than the peripheral blood. When the fraction of bone marrow and peripheral blood samples that reacted with CD34 and CD14 were tested for the combination of CD105, CD106, and CD36, a smaller percentage of cells from the bone marrow reacted with CD36 than those from peripheral blood, suggesting that CD36 does not express for mesenchymal stem cells (MSCs). Bone-marrow aspirate seems to contain a significantly greater percentage of hematopoietic, endothelial, and MSCs than peripheral blood. Of particular significance is the higher percentage of bone-marrow cells reacting to CD105, an indication of the presence of MSCs. The ability of multipotent MSCs to form osteoblasts for bone regeneration makes transplanted bone-marrow aspirate a promising tool for enhancing bone regeneration. |
Effects of tocotrienol from Bixa orellana (annatto) on bone histomorphometry in a male osteoporosis model induced by buserelin.
Osteoporosis is a debilitating skeletal side effect of androgen deprivation therapy based on gonadotropin-releasing hormone (GnRH) agonist in men. Tocotrienol from Bixa orellana (annatto) has been demonstrated to offer protection against osteoporosis by exerting anabolic effects on bone. Thus, it may prevent osteoporosis among GnRH agonist users. This study aimed to determine the effectiveness of annatto-tocotrienol on the bone turnover markers and bone histomorphometry in a model of male osteoporosis induced by buserelin (a GnRH agonist). Forty-six three-months-old male Sprague-Dawley rats (three months old; 300-350 g) were randomly divided into six groups. The baseline control group (n = 6) was sacrificed at the onset of the study. The normal control group (n = 8) received corn oil (the vehicle of tocotrienol) orally daily and normal saline (the vehicle of buserelin) subcutaneously daily. The buserelin control (n = 8) received corn oil orally daily and subcutaneous buserelin injection 75 μg/kg/day daily. The calcium control (n = 8) received 1% calcium in drinking water and subcutaneous buserelin injection 75 μg/kg/day. The remaining rats were treated with two different treatments, i.e., (1) oral annatto tocotrienol at 60 mg/kg/day plus subcutaneous buserelin injection 75 μg/kg/day (n = 8); (2) oral annatto tocotrienol at 100 mg/kg/day plus subcutaneous buserelin injection 75 μg/kg/day (n = 8). The rats were injected with calcein twice before being sacrificed to label the bones. The rats were euthanized, and their blood and right femur were harvested at the end of the treatment for bone turnover markers and bone histomorphometry examination. Both serum osteocalcin and C-telopeptide of type 1 collagen were not significantly different between treated groups and buserelin control (P > 0.05). The buserelin control group had a significantly lower bone volume and higher eroded surface compared with the normal control group (P < 0.05). Both groups treated with annatto tocotrienol (60 mg/kg/day and 100 mg/kg/day) had significantly higher bone volume, trabecular thickness and osteoblast number, as well as a significantly lower single-labelled surface compared with the buserelin control (P < 0.05). Only rats treated with annatto tocotrienol 60 mg/kg/day had a significantly higher double-labelled surface compared with buserelin control (P < 0.05). Annatto tocotrienol can prevent trabecular bone loss by increasing the mineralising surface and osteoblasts number. Thus, it has a potential role in preventing bone loss in men using GnRH agonist. |
Triple co-culture of human alveolar epithelium, endothelium and macrophages for studying the interaction of nanocarriers with the air-blood barrier.
Predictive in vitro models are valuable alternatives to animal experiments for evaluating the transport of molecules and (nano)particles across biological barriers. In this work, an improved triple co-culture of air-blood barrier was set-up, being exclusively constituted by human cell lines that allowed to perform experiments at air-liquid interface. Epithelial NCI-H441 cells and endothelial HPMEC-ST1.6R cells were seeded at the apical and basolateral sides of a Transwell® membrane, respectively. Differentiated THP-1 cells were also added on the top of the epithelial layer to mimetize alveolar macrophages. Translocation and permeability studies were also performed. It was observed that around 14-18% of 50-nm Fluorospheres®, but less than 1% of 1.0 µm-Fluorospheres® could pass through the triple co-culture as well as the epithelial monoculture and bi-cultures, leading to the conclusion that both in vitro models represented a significant biological barrier and could differentiate the translocation of different sized systems. The permeability of isoniazid was similar between the epithelial monoculture and bi-cultures when compared with the triple co-culture. However, when in vitro models were challenged with lipopolysaccharide, the release of interleukin-8 increased in the bi-cultures and triple co-culture, whereas the NCI-H441 monoculture did not show any proinflammatory response. Overall, this new in vitro model is a potential tool to assess the translocation of nanoparticles across the air-blood barrier both in healthy state and proinflammatory state. STATEMENT OF SIGNIFICANCE: The use of in vitro models for drug screening as an alternative to animal experiments is increasing over the last years, in particular, models to assess the permeation through biological membranes. Cell culture models are mainly constituted by one type of cells forming a confluent monolayer, but due to its oversimplicity they are being replaced by three-dimensional (3D) in vitro models, that present a higher complexity and reflect more the in vivo-like conditions. Being the pulmonary route one of the most studied approaches for drug administration, several in vitro models of alveolar epithelium have been used to assess the drug permeability and translocation and toxicity of nanocarriers. Nevertheless, there is still a lack of 3D in vitro models that mimic the morphology and the physiological behavior of the alveolar-capillary membrane. In this study, a 3D in vitro model of the air-blood barrier constituted by three different relevant cell lines was established and morphologically characterized. Different permeability/translocation studies were performed to achieve differences/similarities comparatively to each monoculture (epithelium, endothelium, and macrophages) and bi-cultures (epithelial cells either cultured with endothelial cells or macrophages). The release of pro-inflammatory cytokines (namely interleukin-8) after incubation of lipopolysaccharide, a pro-inflammatory inductor, was also evaluated in this work. |
NILU-UV multi-filter radiometer total ozone columns: Comparison with satellite observations over Thessaloniki, Greece.
This study aims to construct and validate a neural network (NN) model for the production of high frequency (~1min) ground-based estimates of total ozone column (TOC) at a mid-latitude UV and ozone monitoring station in the Laboratory of Atmospheric Physics of the Aristotle University of Thessaloniki (LAP/AUTh) for the years 2005-2014. In the first stage of model development, ~30,000 records of coincident solar UV spectral irradiance measurements from a Norsk Institutt for Luftforskning (NILU)-UV multi-filter radiometer and TOC measurements from a co-located Brewer spectroradiometer are used to train a NN to learn the nonlinear functional relation between the irradiances and TOC. The model is then subjected to sensitivity analysis and validation. Close agreement is obtained (R2=0.94, RMSE=8.21 DU and bias=-0.15 DU relative to the Brewer) for the training data in the correlation of NN estimates on Brewer derived TOC with 95% of the coincident data differing by less than 13 DU. In the second stage of development, a long time series (≥1 million records) of high frequency (~1min) NILU-UV ground-based measurements are presented as inputs to the NN model to generate high frequency TOC estimates. The advantage of the NN model is that it is not site dependent and is applicable to any NILU input data lying within the range of the training data. GOME/ERS-2, SCIAMACHY/Envisat, OMI/Aura and GOME2/MetOp-A TOC records are then used to perform a precise cross-validation analysis and comparison with the NILU TOC estimates over Thessaloniki. All 4 satellite TOC dataset are retrieved using the GOME Direct Fitting algorithm, version 3 (GODFIT_v3), for reasons of consistency. The NILU TOC estimates within ±30min of the overpass times agree well with the satellite TOC retrievals with coefficient of determination in the range 0.88≤R2≤0.90 for all sky conditions and 0.95≤R2≤0.96 for clear sky conditions. The mean fractional differences are found to be -0.67%±2.15%, -1.44%±2.25%, -2.09%±2.06% and -0.85%±2.19% for GOME, SCIAMACHY, OMI and GOME2 respectively for the clear sky cases. The near constant standard deviation (~±2.2%) across the array of sensors testifies directly to the stability of both the GODFIT_v3 algorithm and the NN model for providing coherent and robust TOC records. Furthermore, the high Pearson product moment correlation coefficients (0.94<R<0.98) testify to the strength of the linear relationship between the satellite algorithm retrievals of TOC and ground-based estimates, while biases of less than 5 DU suggest that systematic errors are low. This novel methodology contributes to the ongoing assessment of the quality and consistency of ground and space-based measurements of total ozone columns. |
Heterogeneity in the fractionation sensitivities of human tumor cell lines: studies in a three-dimensional model system.
Current concepts to optimize the therapeutic gain of radiotherapy by hyperfractionation assume that human tumors are less sensitive to fractionation than late reacting normal tissues. The aim of this study was to investigate the extent of the intercell line heterogeneity of fractionation sensitivity of a wide variety of human tumor cell lines in a three-dimensional model system under fully oxic conditions using schedules with one to eight fractions. Biological characteristics of the tumors that correlate with fractionation sensitivity should be identified. A total of 21 cell lines from human tumors maintained as multicellular spheroids consisting of 1000-1500 cells were given fractionated irradiation within a total treatment time of maximally 50 h. Complete dose-spheroid control curves were determined for each fractionation scheme. The spheroid control data were adequately described by the linear quadratic model assuming Poisson statistics. In addition, the induction of a G2 block by a fractionated test dose of seven 3 Gy fractions given at 6-h intervals was determined in spheroid cells using flow cytometry of propidium bromide stained cell nuclei. The fractionation sensitivities of human tumor cells in multicellular spheroids could be characterized by alpha/beta values, ranging from 2.8-37 Gy in dependence on the cell line. The log normally distributed alpha/beta values were positively correlated with the percentage increase in G2/M phase after the fractionated test dose compared to the controls (r = 0.72, p < 0.01), and were associated with the degree of tumor differentiation (p = 0.01, ANOVA F-test). No significant correlation between the log (alpha/beta) values and the surviving fractions at 2 Gy (SF2) or the total doses with 2 Gy per fraction necessary to control 50% of the spheroids (SCD50) was observed. Despite the intercell line variability of the alpha/beta values, the SCD50 values of the different cell lines, given with one and eight fractions or one fraction and 2 Gy per fraction, were closely associated (Spearman rank correlation coefficients: r = 0.89 or r = 0.90, p < 0.0001). Human tumor cell lines showed a marked heterogeneity in the fractionation sensitivity when irradiated as multicellular spheroids and assayed in situ using the spheroid control end point. Therefore, the therapeutic gain of altered fractionation also depends on those biological characteristics of each individual tumor that affects its fractionation sensitivity. Parameters that correlate with fractionation sensitivity of the tumor lines in the spheroid system were identified as grade of tumor differentiation and percentage increase in G2/M cells at the end of an eight-fraction schedule. |
Real-time, volumetric echocardiography: usefulness of volumetric scanning for the assessment of cardiac volume and function.
A novel imaging system has been introduced which uses a dedicated two-dimensional echo probe for rapid beam forming to scan a pyramidal volume in real time. Real-time volumetric echocardiography has the potential to determine accurate cardiovascular anatomy, volume and function in the beating heart without reconstructions. The results of animal and human studies using volumetric echocardiography are evaluated for the potential for clinical applications. IMAGING METHODOLOGY: A new type of ultrasound imaging, high-speed volumetric scanning based on phased array principles permits real-time three-dimensional, volumetric echocardiography (real-time 3-DE). The system requires no off-line reconstruction techniques, thus enabling dynamic three-dimensional visualization and quantification of the heart in real time using a transthoracic approach. Real-time 3-DE uses a 2-D matrix phased array transducer. Image formation employs 16:1 parallel processing to scan a pyramidal volume composed of multiple steering directions in the azimuth dimension and in the elevation dimension. The finished transducer is mounted in a hand-held case with a circular aperture of 16 mm diameter. The array consists of approximately 1,600 elements, operating at 2.5 MHz. Real-time 3-DE permits simultaneous, multiple plane display of two sector arcs (B-scans) and C-scan (parallel to the transducer face or inclined) on a single monitor, conveying the three-dimensional nature of the ultrasound data. This system also allows these planes to be angled for extra diagnostic flexibility. The motion of all the structures during the cardiac cycle can be evaluated in dynamic mode. Real-time 3-DE was assessed for accuracy of volume measurement by measuring the volume of balloons of different size and shape, and the hearts of 15 closed chest dogs with myocardial contrast enhancement, and compared to the volumes measured by left ventricular angiography in the dogs. Real-time 3-DE was used to evaluate the endocardial border determination of the entire left ventricle by injecting contrast agent in 12 patients. The endocardial border determination of each segment was scored, and the endocardial border score index calculated. Both real-time 3-D images and cine magnetic resonance imaging (MRI) were performed in 16 patients to assess the accuracy of volume measurement of the left ventricle in humans. The endocardial border of the left ventricle was manually traced, and the volumes calculated by Simpson's rule. The volumes measured by real-time 3-DE correlated well with the true volumes for different sizes of balloon and for asymmetric balloons. The end-diastolic volume and end-systolic volume linear correlation of real-time 3-DE versus angiography measurements using manual tracing in vivo also gave a good correlation (r = 0.97, p < 0.001; r = 0.92, p < 0.01). Fifty-eight of 192 segments were rated as good at baseline and 143 rated as good after Levovist injection. Endocardial border determination was improved by Levovist injection in 100 of 137 segments (74.6%). The endocardial border score index was significantly higher after Levovist administration than at baseline (p < 0.003). The end-diastolic volume and end-systolic volume of the left ventricle measured by real-time 3-DE in humans correlated well with those measured by MRI (end-diastolic volume: r = 0.97, p < 0.001; end-systolic volume: r = 0.96, p < 0.001). Transthoracic real-time, volumetric echocardiography opens a new and exciting field of echocardiography. The results of these studies demonstrate that this system can accurately measure the ventricular volume and function without use of geometric assumptions. This volumetric mode or V-mode scanning is a new imaging modality that provides a practical methodology to investigate important clinical and research questions. |
First Report of Umbel Browning and Stem Necrosis Caused by Diaporthe angelicae on Carrot in France.
In 2011, carrot (Daucus carota L.) seed production occurred on 2,900 ha, which accounts for approximately 25% of the area devoted to the production of vegetable fine seeds. Since 2007, symptoms of umbel browning have been regularly observed in carrot production areas located in the central region. Initially, triangular necrotic lesions appeared on carrot umbels that later spread to the entire umbels and often progressed to the stems. Diseased umbels became dried prematurely, compromising seed development. The loss in seed production was estimated at approximately 8% of the harvested carrot umbels during the cropping seasons of spring and summer 2007 and 2008 in France. In collaboration with seed companies, diseased carrot stems were collected from seven fields of seed production (eight plants per field) and a fungus was isolated from the tissue. The cultures were grown on malt (2%) agar (1.5%) medium and incubated for 2 weeks at 22°C in darkness. Young fungal colonies were white and a brownish green pigmentation developed when the colonies became older. The same color was observed from the top and on the reverse of the colonies. To induce sporulation, isolates were grown on water agar (1.5%) medium in the presence of carrot stem fragments for 1 week at 22°C in darkness, followed by 1 week at 22°C in white light under a 16-h photoperiod. Pycnidia were produced on stem fragments and contained alpha and beta conidia typical of the genus Diaporthe (2). Alternatively, pycnidia were also obtained on malt agar medium after 2 weeks of culture at 25°C in white light under a 12-h photoperiod. The size of alpha and beta conidia was 6.3 ± 0.5 × 2.3 ± 0.4 μm and 23.3 ± 1.8 × 0.9 ± 0.2 μm, respectively (n = 170). In order to confirm the identification at the genus level and determine the species, DNA was extracted from the mycelium of three representative isolates and the ITS regions of the ribosomal DNA were amplified using universal primers (1). The sequences of the amplified products (GenBank Accession Nos. KF240772 to KF240774) were 100% identical with the ITS sequence of a Diaporthe angelicae isolate deposited in the NCBI database (CBS 111592 isolate, KC343027). To confirm pathogenicity, the three isolates of D. angelicae were inoculated on carrot umbels in the greenhouse. A total of nine plants were inoculated (three plants per isolate). Using a micropipette, 10 μl of a conidial suspension containing alpha and beta conidia (105 conidia mL-1) were deposited at the base of the primary umbel and two secondary umbels, which were wounded before inoculation using a scalpel blade. Seven inoculated plants developed triangular, necrotic lesions that were typical umbel browning. D. angelicae was re-isolated on malt agar medium from the inoculated diseased carrot umbels. To our knowledge, this is the first report of D. angelicae in carrot cultivated for seed production in France. The disease resembles the lesions described in the Netherlands in 1951 on carrot inflorescence caused by Phomopsis dauci (3). In future experiments, it would be crucial to precisely determine if D. angelicae could be transmitted to the seeds. References: (1) M. A. Innis et al. PCR Protocols: A Guide to Methods and Applications. Academic Press, San Diego, CA, 1990. (2) J. M. Santos and A. J. L. Philips. Fungal Divers. 34:111, 2009. (3) J. A. von Arx. Eur. J. Plant Pathol. 57:44, 1951. |
Ultrasound evaluation of the anatomical characteristics of the internal jugular vein and carotid artery--facilitation of internal jugular vein cannulation.
Literature review revealed major variations in the anatomic characteristics of the right internal jugular vein (IJV) and carotid artery (CA) by the use of the ultrasound machine. The purpose of this study is to examine the anatomical characteristics of the right IJV and CA and to evaluate the IJV cannulation outcomes by the standard ultrasound guided vs. ultrasound localized technique as suggested by Lin and colleagues. Additionally, the study assessed the impact of changing the ultrasound transducer direction on the location of right IJV relative to the CA METHODS: Patients (n = 100) were randomly assigned to either and ultrasound-guided or ultrasound-localized technique for IJV cannulation. The 'Site Rite' II ultrasound transducer was directed perpendicular to the floor at the apex of the clavicle-sternocleidomastoid triangle at the level of the cricoid cartilage with the head turned to contralateral side of cannulation and table tilted to 30 degrees in Trendelenburg position. Cannulation outcomes, including successful cannulation, access time, success time, and difficult cases were evaluated. Aborted difficult cases included prolonged procedural time exceeding four minutes and carotid puncture, and these were examined by technique, IJV size and its location relative to CA. The location of the IJV relative to CA was evaluated firstly with the ultrasound transducer directed perpendicular to the floor and secondly with the transducer directed perpendicular to the skin (Fig 1). With the ultrasound transducer directed perpendicular to the floor, the depth of the IJV from the skin (15 mm) was comparable to its diameter (14.1 mm), while the CA A-P diameter was around half that of the IJV (7.4 mm) (Table 2). Also, the majority of patients showed lateral (51%) and posterolateral (14%) positions of the IJV relative to the CA. Directing the transducer perpendicular to the skin resulted in more anterolateral positions (77%) with 6% total overlap. Cannulation of the IJV was successful in 94% in both randomization groups, with 91.5% of the patients achieving first pass cannulation in the ultrasound-guided group and 87.2% in the ultrasound-localized (Table 3). Access time (6.9 +/- 13 sec and 5.9 +/- 14.6 sec) and success time (13.5 +/- 14.2 sec and 13.2 +/- 15.0 sec) were comparable for both groups. Reasons for aborted difficult cannulation included prolonged procedural time in 2% and carotid puncture in 4%, in both techniques. Compared to the successful cases, difficult cases were characterized by a significantly greater degree of anterolateral (exceeding 15 degrees) location ofthe IJV relative to the CA(p-value = 0.046) and a significantly smaller IJV size (mean 10.3 mm vs. 14.3 mm, p-value = 0.035) (Table 4). However, in multivariate analysis controlling for the technique utilized, only the relation between the size of IJV and the occurrence of difficult cases remained significant. With each 1 mm decrease in IJV size, there was a 37% significant increase in the risk of difficult cases. Findings of the study show that both ultrasound guided and ultrasound localized techniques yield similar cannulation outcomes. Additional to the anteraloteral position of the IJV relative to the CA, a small IJV size constitutes a powerful predictor for the incidence of prolonged procedure time and carotid puncture for IJV canulation. Finally, the transducer direction has a significant impact on the assessment of the location of the IJV relative to the CA. |
Structural features of the binding site of cholera toxin inferred from fluorescence measurements.
The dependence on pH of the fluorescence of cholera toxin and its A and B subunits has been studied at 25 degrees C. The fluorescence intensity of cholera toxin is highly pH-dependent. In the pH range 7-9.5 it reaches a maximum corresponding to a quantum yield of 0.076. In the pH range 4-7 a strong increase in fluorescence intensity is observed (delta Q/Qmax = 0.64). Evaluation of the pH sensitivity of the fluorescence intensity of the A and B subunits reveals that the B subunit is mainly responsible for the observed pH effect (delta Q/Qmax for B subunit = 0.64). The intensity changes are paralleled by similar although less pronounced changes in the average fluorescence excited state life-time tau (delta tau/tau max = 0.33 for cholera toxin). Fluorimetric titration of the B subunit, which is related to the indole fluorescence of the lone Trp-88, reveals that the fluorescence intensity changes in the pH range 4-7 are due to reaction of two types of ionizable quencher displaying apparent pKa values of 4.4 and 6.2, respectively. It is suggested that the increase in fluorescence intensity with a midpoint at pH 6.2 is the result of deionization of the imidazolium side-chain of one or two out of the four histidine residues present in each beta-polypeptide chain, whereas a deionized carboxyl group is responsible for the quenching with midpoint at pH 4.4. Complex formation of cholera toxin or B subunit with the monosialoganglioside GM1 or the oligosaccharide moiety of GM1 (oligo-GM1) completely prevents the quenching by both quenchers. Addition of 6 M urea also eliminates the pH effect. The quenching is not the result of the dissociation of the B subunit into its constituent monomers. Upon fluorimetric titration of cholera toxin or B subunit above pH 9, a progressive drop in both fluorescence intensity and tau occurs. This decrease could be due to energy transfer from the indole moiety of Trp-88 to ionized tyrosines or by quenching through an unprotonated epsilon-amino group of lysine. Fluorimetric titration of the A subunit indicates that the tryptophan fluorescence is only moderately altered by ionizable groups displaying a pKa in the range 4 to 9. Activation of A subunit does not affect this lack of pH sensitivity. Above pH 9, however, a much more significant drop in the fluorescence intensity of activated A subunit occurs. The structural implications of the results are discussed. |
Induction of the heat shock response in rats modulates heart rate, creatine kinase and protein synthesis after a subsequent hyperthermic treatment.
STUDY OBJECTIVE - The aim of the study was to examine the effect of prior induction of the heat shock response on heat shock protein synthesis and physiological variables relevant to the shock response. DESIGN - Synthesis of heat shock protein (SP71, molecular mass 71,000) was induced in rats by 15 min hyperthermia (42 degrees C). Protein synthesis, heart rate, blood pressure and creatine kinase activity were determined in comparison with controls (no heat shock) and a group receiving two heat shock treatments 24 h apart (prior induction group). SUBJECTS - 24 male Sprague-Dawley rats (125-150 g) were used, divided into three groups: controls (n = 4), heat shock X 1 (HS, n = 11), heat shock X 2 (2 X HS, n = 9). Heat shock was induced under anaesthesia on a heating pad. MEASUREMENTS and RESULTS - Blood pressure and heart rate were measured at the beginning of the hyperthermia period, when body temperature first reached 42 degrees C (t = 0 min) and at the end of the hyperthermia treatment (t = 15 min). At t = 0 min systolic blood pressure and heart rate were increased compared to the control values in both HS and 2 X HS groups. At t = 15 min heart rate in the HS group was increased to 554 (SEM21) beats.min-1 v control 465(19) (p less than 0.05). In the 2 X HS group, heart rate of 494(14) beats.min-1 at t = 15 min was not significantly different from control. At t = 15 min, creatine kinase values in the hyperthermia treatment groups were not different from control. However at 2.5 h after hyperthermic treatment plasma creatine kinase was increased in the HS group to 481(83) mU.ml-1 (n = 6) v 223(20) in controls, but was not increased in the 2 X HS group [178(64), n = 4]. Rats were radiolabelled for 2 h with 1.0 mCi of [35S]-methionine 30 min after hyperthermic treatment in HS group and 30 min after the second hyperthermic treatment in 2 X HS group. Following the 2 X HS treatment, synthesis of SP71, though increased above control values, was lower than in the HS group. CONCLUSIONS - The reduction in heart rate, plasma creatine kinase and synthesis of SP71 following a second hyperthermic exposure could be caused by a protective influence of the first exposure. |
[The relationships among self-identity, self-esteem and attitude towards sexual behavior in university students].
It has been reported that the young people of today tend to engage in sexual behavior at an early age and the abortion rate is high. The purpose of this study was to investigate the attitudes of post-adolescents with regard to sexual behaviors and the relationship to self-identity and self-esteem. The subjects were 234 males (mean +/- SD 20.2 +/- 1.1 years) and 460 females (mean +/- SD 19.5 +/- 1.1 years) 4-year university students aged 18 to 23 years in Aichi Prefecture. An anonymous, self-report questionnaire was used to survey the subjects with regard to self-identity ("Establishment of Self" scale), self-esteem (Rosenberg Self-Esteem Scale), and sexual attitude and behavior. The scores on both scales and subscales of the "Establishment of Self" scale, "Foundation of Identity (Foundation)" and "Establishment of Identity (Establishment)", were calculated and intercompared, along with sexual attitude and behavior, controlled for age and school type. The mean total score of the "Establishment of Self" scale for males was 55.3 (SD9.2) and for females 52.2 (SD9.3), while those for the Rosenberg Self-Esteem Scale were 27.2 (SD5.5) and 25.7 (SD5.2), respectively. There was significant positive correlation all scales in both sexes. Both male and female students had positive attitude towards sex and a negative view of "traditional gender roles" particularly females. Of the subjects, 82.4% of males and 69.5% of females were thinking of accepting a request for sexual intercourse from their partners. Many students understood the "need for contraception", that is a component of contraceptive behavior. Most of them, however, didn't acquire the other components. A total of 68.3% of males and 48.2% of females had experienced sexual intercourse during the last year. Of these, 50.6% of males and 58.2% of females consistently used contraception. The score on the "Establishment of Self" scale was higher among both the male and female students who responded positively to having "communication ability," "learning ability," and "acquisition ability." Significant differences were found in total and "Establishment" scales among males, and all scales among females. The score on the Rosenberg Self-Esteem Scale was significantly higher with "learning ability" among males, and with "communication ability" and "learning ability" among females. However, no significant relationship was found between actual contraceptive behavior and any of the scales. In dealing with contraception, a gap exists between university students' attitudes and actual behavior. The scores on the "Establishment of Self" scale and the Rosenberg Self-Esteem Scale were found to be significantly higher for those who exhibited higher values for components of contraceptive behavior. |
The experiences of people living with epilepsy in developing countries: a systematic review of qualitative evidence.
Epilepsy is a global public health problem affecting people of all ages, sex, races, nations and social class. The majority of the 50 million people with epilepsy live in developing countries, with a prevalence rate of five to 10 people per 1000. The disease poses an enormous psychological, social and economic burden on patients. An estimated 90% of people with epilepsy in developing countries do not receive treatment due to sociocultural, economic and political factors. Current treatment interventions are limited to the clinical management of the disease and are largely driven by the healthcare provider's perspective, ignoring the experiences of people living with epilepsy (PLWE). The aim of this review was to identify, critically appraise, extract, synthesize and present the best and most current available evidence on the experiences of PLWE in developing countries. • What are the experiences of PLWE regarding the causes of their condition?• What are the experiences of PLWE regarding treatment of epilepsy?• How has epilepsy shaped the social relationships of the affected persons? People living with epilepsy in developing countries (Africa, Asia, Eastern Europe and Latin America).The experiences of PLWE in developing countries with particular attention on the causes, treatment and its impact on their social relationships.Primary research studies with a qualitative design not limited to phenomenology, ethnography, grounded theory, ethnomethodology, phenomenography, critical theory, interpretative or feminist analysis, case study, narrative studies and action research. Qualitative studies conducted in hospitals and community settings in developing countries. A three-step search strategy was used to identify published and unpublished studies in the English language from the 1990s to the present. Identified studies that met the inclusion criteria were retrieved and critically appraised by two independent reviewers prior to their inclusion using the Joanna Briggs Institute Qualitative Assessment and Review Instrument (JBI-QARI). Data were extracted from included papers using the recommended data extraction form embedded in the JBI-QARI. Findings, where possible, were pooled using the JBI-QARI. It involved the meta-aggregation of findings to generate a set of statements that represented that aggregation, through assembling the findings rated according to their quality, and categorizing these findings on the basis of similarity in meaning. From the 13 studies included in the review, 113 findings were extracted to create categories. Eight categories were created from which three synthesized findings were produced. The synthesized findings were: SYNTHESIZED FINDING 1: People living with epilepsy believed that the disease was caused by factors such as fever, demonic power, beatings, witchcraft, curses and God. Patients also had differing views as to whether the disease was contagious or hereditary. They indicated that the disease manifested as seizures, triggered by fever, stress, depression and anger. SYNTHESIZED FINDING 2: People living with epilepsy used biomedical and traditional methods to treat epilepsy and also developed strategies for coping with the disease beyond seeking treatment. SYNTHESIZED FINDING 3: People living with epilepsy had negative and positive experiences in their social relationships. The negative experiences were linked to the social, psychological and economic burden of the disease on patients, whereas the social support they got from friends, peers, family and community members were the positive aspects. People living with epilepsy attribute the cause of the disease to agents like fever, demonic power and witchcraft. Patients use biomedical and traditional methods to treat the disease and have also developed various coping strategies (like prayers and concealment) alongside treatment. Epilepsy has negative effects on the social relationships of patients and is a social, psychological and economic burden for patients. However, there are some positive effects like the social support they receive from family members, friends and the community. |
Experiences with microsurgical tissue transfers in elderly patients.
The combination of advances in microsurgery and the improvement of anesthetic management with increased understanding of the physiology of preoperative and postoperative care has significantly raised the upper age limit for free-flap transfer in elderly patients. Despite pessimistic opinions regarding elderly patients who have poor recovery potential and decreased physiological reserves, the unique feature of free-tissue transfer is that it allows the transfer of well-vascularized tissue to defects in a single-stage procedure, and leads to improved quality of life. In this report, a retrospective analysis of 55 patients aged 50 and older who underwent microsurgical tissue transfer is presented. Hospital and our own records were used to review various parameters. The preoperative medical status of each patient was assessed using the American Society of Anesthesiologists (ASA) Classification of Physical Status. Each patient's preoperative medical records, age, sex, transferred tissue type, and length of operation were outlined. Postoperative recorded parameters were the fate of flaps and the short-term postoperative outcome, including surgical complications, medical morbidity, and death within 30 days of surgery. Fifty-eight microvascular tissue transfers were performed in 55 consecutive patients. The study comprised 38 male and 17 female patients, with a mean age of 64.8 years. ASA classification status was class 1 for 15 patients, class 2 for 26 patients, and class 3 for 14 patients. Twenty-five flaps were used for lower extremity reconstruction, 32 flaps were used for head and neck reconstruction, and 1 was used for breast reconstruction. The average operative time was 5.7 h, ranging between 2-13 h. There were 14 major medical complications, resulting in an overall medical complication rate of 25%. There were 3 deaths within 30 days postoperatively. Thus, the overall surgical mortality rate was 5.4%. The longer operation times were associated with the development of postoperative total medical and surgical complications (P = 0.008). While the relationship between ASA class and medical complications was significant (P = 0.0007), no significant relation was determined between ASA class and surgical complications (P = 0.66). It was revealed that the greater the age group, the greater the occurrence of postoperative medical complications (P = 0.0001). The relationship between postoperative surgical complications and age groups was not significant (P = 0.07). It was also demonstrated that the advanced age of patients was associated with a higher ASA class (P = 0.0017). Eleven flaps required reoperation for vascular compromise. While 10 of these were salvaged with vascular anastomosis revisions, one flap was lost. Thus the overall flap success rate was 98.3%. In conclusion, if a patient's medical problems do not constitute a handicap, age itself should not be considered a barrier to free-flap transfer. It is important to be familiar with preoperative medical problems and possible postoperative medical complications in order to achieve a successful outcome. Contrary to what is generally suggested, surgical complications do not constitute a special consideration in older patients. |
Clinical and dietary indicators associated with uremic status in hospitalized dialysis patients.
The objective of this study was to determine whether any differences existed between specific admission variables and uremic status in patients with chronic renal failure receiving dialysis. This was a prospective, observational study conducted at BryanLGH Medical Center East Campus in Lincoln, Nebraska. The subjects were hemodialysis and peritoneal dialysis patients admitted to an acute care facility, who met the following inclusion criteria: (1) they had a primary or secondary underlying diagnosis of chronic renal failure, and (2) they were not receiving parenteral or enteral tube feeding nutritional support on admission. The patients were separated into 2 groups by their blood urea nitrogen (BUN) concentrations. Group 1 had a BUN concentration less than 50 and group 2 had a BUN concentration greater than or equal to 50. Admission data (age, sex, percentage of ideal body weight, reported retrospective weight loss over time, type of dialysis, gastrointestinal history, BUN and creatinine concentrations, and dietary prescription) were collected from patient medical records. Two-day kilocalorie and protein counts were conducted on the patients within 24 hours of admission to the acute care facility. Chi-square and 1-way analysis of variance were performed to compare the groups. The total number of participants in the study was 42, with 21 in each BUN group. The mean age was 60 years, and the dietary intake was a mean of 10 kcal/kg and 0.4 g protein/kg. Only 14.3% and 7.1% of the patients met their kcal and protein needs, respectively. The mean percentage ideal body weight was 125 and the mean reported weight loss per week was 2.6 pounds. Gastrointestinal symptoms, specifically nausea and a kilocalorie-restricted diet prescription, were significantly different between the 2 groups. Patients in group 2 were more likely to have gastrointestinal symptoms overall (P < .05) specifically, nausea (P <.05). Group 1 patients were also more frequently placed on a kilocalorie-restricted diet (P < .05) than patients in group 2. A BUN concentration between 50 and 110 has been shown to be associated with a lower risk of death and a better nutritional status. These findings indicate symptoms commonly associated with uremia, such as nausea, may be associated with the dialysis patient's nutritional status when BUN concentrations are greater than 50. These dialysis patients were not receiving sufficient kilocalories and protein on admission into the hospital, and this can affect their nutritional and, eventually, survival status. |
Comparison of heroin and cocaine concentrations in saliva with concentrations in blood and plasma.
Saliva is an alternate biological matrix for drug testing that has several advantages over more traditional fluids such as blood and urine. Collection is rapid, noninvasive, and relatively easy to obtain. Several reports have detailed the appearance of drugs of abuse in saliva, but few have compared the excretion profiles of drugs administered by different routes. In this study, subjects were administered three smoked and three intravenous doses of heroin in an ascending dose design. Blood and saliva were collected periodically after drug administration and analyzed by gas chromatography-mass spectrometry (GC-MS) for heroin, 6-acetylmorphine, and morphine. In a second study, subjects were administered a single, smoked dose of 40 mg cocaine base and an intravenous dose of 44.8 mg cocaine HO on separate occasions. Plasma and saliva were collected and analyzed by CC-MS for cocaine, anhydroecgonine methyl ester (AEME), and seven additional metabolites. Heroin and 6-acetylmorphine were detected in the first saliva sample collected (2 min) following drug administration by both routes. Peak heroin concentrations were achieved quickly, between 2 and 5 min after intravenous administration and at 2 min after smoke heroin. Peak heroin concentrations in saliva after smoking heroin base ranged from 3534 (2.6 mg) to 20,580 ng/mL (5.2 mg), and after intravenous administration, concentrations ranged from 6 (10 mg heroin HCl to 30 ng/mL (12 mg heroin HCl. Saliva concentrations of heroin declined rapidly after intravenous administration, reaching the limit of sensitivity of the assay (1 ng/mL) by 60 min. Heroin concentrations in saliva after smoking declined slowly; detection times ranged from 4 to 24 h. Cocaine was the major analyte detected in saliva and plasma after smoked and intravenous administration. Peak saliva cocaine concentrations after intravenous administration ranged from 428 to 1927 ng/mL (N = 7); after smoking, they ranged from 15,852 to 504,880 ng/mL (N = 7). Peak plasma cocaine concentrations after intravenous administration ranged from 122 to 442 ng/mL A = 7), and after smoking, concentrations ranged from 46 to 291 ng/mL A = 7). The thermal degradation product of cocaine, AEME, was detected in saliva but not in plasma after smoking. Peak saliva AEME concentrations were achieved at 2 min and ranged from 558 to 4374 ng/mL (N = 7). These are the first reported observations of heroin and metabolites in saliva following heroin smoking and of AEME in saliva after smoking cocaine base. The presence of AEME in saliva may be useful as a marker of the smoked route following cocaine administration. |
[Safety of rice grains and mycotoxins - a historical review of yellow rice mycotoxicoses].
Aflatoxins, the most powerful mycotoxins, were brought to the attention fo the people in the early 1960s with the outbreak of the turkey "X" disease in England. However, the history of mycotoxin research in Japan began 100 years ago. In 1891, Sakaki demonstrated that moldy, unpolished rice was fatal to experimental animals, with symptoms indicating paralysis of the central nervous system (Shoshin-kakke). In 1920, Prof. I. Miyake and Dr. Takada first reported that Penicillium commune, which was known as a causal agent of "Mossy diseased rice" was found to be toxic to experimental animals by feeding the moldy rice to rabbits and rats.With such a historical background, taking the idea of "rice, fungus and toxin" as a working hypothesis, Miyake and his co-workers discovered the first sample of yellow rice grains from Taiwanese and domestic rice, from which was isolated a species of Penicillium and later identified it with P. citreonigrum (=P. toxicarium). The fungus produced a highly toxic metabolite, citreoviridin. Unfortunately because this study was published during wartime, it failed to alert the world to the potential or actual dangers of the toxicity of common molds. After World War II, Japanese people suffered for some years from a shortage in domestic rice production and depended on foreign countries to supply rice, which led to the toxicological screening on fungal isolates from polluted rice grains by Dr. Tsunoda and his co-workers. AMong the isolates from imported rice, there were two species of Penicillium which were particularly associated with high toxicity; P. islandicum responsible for brownish discolored rice, and P. citrinum responsible for yellowish rice. P. islandicum produces two hepatotoxic metabolites: luteoskyrin and cyclochlorotine, while a nephrotoxic of P. citrinum is citrinin. These toxicological characters, including the induction of cancer and chemical structures, were studied by Profs. uraguchi, Saito, Shibata, Tatsuno and their co-workers. In this way, toxic disturbances associated with the consumption of rice contaminated with these Peniciliium species occurred and became known under the collective name of the "Yellow rice syndrome". Although no human cases of poisoning were recorded, scientists in the field of mycotoxin research recommended to the Japanese Government that administrative action should be taken to protect the people against any possible hazards from "yellow rice". Consequently, mycological inspections of imported rice were started by the government. The safety control system for domestic rice during post-harvest handling and long-term storage has been progressively established after learning of these problems. |
Five years of experience with mitral valve homografts.
The main advantages of mitral homografts are preservation of the subvalvular apparatus and avoidance of life-long anticoagulation. In this communication, we will present our five-year experience using mitral homografts in mitral valve surgery. Since 1996, 14 patients (mean age 46 +/- 8 years, range 27 - 65 years have had mitral homografts implanted. Thirteen patients had mitral valve replacement; the septal leaflet of the tricuspid valve was replaced in one case. The indications were mitral (n = 6) or tricuspid endocarditis (n = 1), mitral valve stenosis (n = 3), and combined mitral valve disease (n = 4). Complete mitral homografts were implanted in eight patients; partial homografts were used in six cases. Preoperatively, the dimensions of the left ventricle and the mitral valve were measured by transoesophageal echocardiography (TOE). The mean left ventricular ejection fraction was 56 +/- 9%, the mean end-diastolic diameter 58 +/- 6 mm. The technique described by Acar/Carpentier was adapted for implantation; a Carpentier ring was implanted in all cases for annular stabilization. The patients had anticoagulative therapy which was discontinued when stable sinus rhythm was present after three months postoperatively. Follow-up included clinical examination, ECG, and echocardiography, and was initiated six months postoperatively and continued on a yearly basis. The following parameters were determined by echocardiography--left atrial size, left ventricular end-diastolic and end-systolic diameter, pressure gradient across the mitral valve (c/w Doppler, Bernoulli's equation), and mitral regurgitation. All patients survived surgery; the mean operation-time was 281 +/- 37 minutes. Intraoperative TOE revealed a first degree insufficiency in 7 patients. Follow-up was completed in all patients, with a mean period of 30 months (6 - 60 months). Two patients had an acute endocarditis two years postoperatively, requiring repeat valve replacement with a mechanical prosthesis. An additional patient had to be reoperated due to chordal rupture three years postoperatively. All three patients had mitral valve stenosis as the initial indication for surgery and had received a complete homograft. In the remaining eleven patients, the morphological and functional state of the implanted grafts remained unchanged during follow-up. The freedom from valve-related events was 93% after one year, 86% after two years, and 79% after three years. At six-month follow-up, ECG and echocardiography revealed sinus rhythm and sufficient atrial contractions in 13 cases. At the last follow-up, the pressure gradients were 3.4 +/- 0.6 mmHg for complete homografts and 2.8 +/- 0.6 mmHg for partial homografts. In five cases, a mild insufficiency was documented, while six patients presented with competent grafts. Mitral homografts can be used with acceptable mid-term results in selected cases with good left ventricular function and only slightly dilated left ventricles. Partial mitral homografts represent an additional technique, especially for mitral valve repair in patients with acute endocarditis. The susceptibility to bacterial infections of a homograft makes strict prophylaxis against endocarditis mandatory. |
Advances in phytase research.
Since its discovery in 1907, a complex of technological developments has created a potential $500 million market for phytase as an animal feed additive. During the last 30 years, research has led to increased use of soybean meal and other plant material as protein sources in animal feed. One problem that had to be overcome was the presence of antinutritional factors, including phytate, in plant meal. Phytate phosphorus is not digested by monogastric animals (e.g., hogs and poultry), and in order to supply enough of this nutrient, additional phosphate was required in the feed ration. Rock phosphate soon proved to be a cost-effective means of supplying this additional phosphorus, and the excess phytin phosphorus could be disposed of easily with the animals' manure. However, this additional phosphorus creates a massive environmental problem when the land's ability to bind it is exceeded. Over the last decade, numerous feed studies have established the efficacy of a fungal phytase, A. niger NRRL 3135, to hydrolyze phytin phosphorus in an animal's digestive tract, which benefits the animal while reducing total phosphorus levels in manure. The gene for phytase has now been cloned and overexpressed to provide a commercial source of phytase. This monomeric enzyme, a type of histidine acid phophatase (HAP), has been characterized and extensively studied. HAPs are also found in other fungi, plants, and animals. Several microbial and plant HAPs are known to have significant phytase activity. A second A. niger phytase (phyB), a tetramer, is known and, like phyA, has had its X-ray crystal structure determined. The model provided by this crystal structure research has provided an enhanced understanding of how these molecules function. In addition to the HAP phytase, several other phytases that lack the unique HAP active site motif RHGXRXP have been studied. The best known group of the non-HAPs is phytase C (phyC) from the genus Bacillus. While a preliminary X-ray crystallographic analysis has been initiated, no enzymatic mechanism has been proposed. Perhaps the pivotal event in the last century that created the need for phytase was the development of modern fertilizers after the Second World War. This fostered a transformation in agriculture and a tremendous increase in feed-grain production. These large quantities of cereals and meal in turn led to the transition of one segment of agriculture into "animal agriculture," with their its animal production capability. The huge volumes of manure spawned by these production units in time exceeded both the capacity of their crops and crop lands to utilize or bind the increased amount of phosphorus. Nutrient runoff from this land has now been linked to a number of blooms of toxin-producing microbes. Fish kills associated with these blooms have attracted public and governmental concern, as well as greater interest in phytase as a means to reduce this phosphorus pollution. Phytase research efforts now are focused on the engineering of an improved enzyme. Improved heat tolerance to allow the enzyme to survive the brief period of elevated temperature during the pelletization process is seen as an essential step to lower its cost in animal feed. Information from the X-ray crystal structure of phytase is also relevant to improving the pH optimum, substrate specificity, and enzyme stability. Several studies on new strategies that involve synergistic interactions between phytase and other hydrolytic enzymes have shown positive results. Further reduction in the production cost of phytase is also being pursued. Several studies have already investigated the use of various yeast expression systems as an alternative to the current production method for phytase using overexpression in filamentous fungi. Expression in plants is underway as a means to commercially produce phytase, as in biofarming in which plants such as alfalfa are used as "bioreactors," and also by developing plant cultivars that would produce enough transgenic phytase so that additional supplementation of their grain or meals is not necessary. Ultimately, transgenic poultry and hogs may produce their own digestive phytase. Another active area of current phytase research is expanding its usage. One area that offers tremendous opportunity is increasing the use of phytase in aquaculture. Research is currently centered on utilizing phytase to allow producers in this industry to switch to lower-cost plant protein in their feed formulations. Development of a phytase for this application could significantly lower production costs. Other areas for expanded use range from the use of phytase as a soil amendment, to its use in a bioreactor to generate specific myo-inositol phosphate species. The transformation of phytase into a peroxidase may lead to another novel use for this enzyme. As attempts are made to widen the use of phytase, it is also important that extended exposure and breathing its dust be avoided as prudent safety measures to avoid possible allergic responses. In expanding the use of phytase, another important consideration has been achieved. Conservation of the world's deposits of rock phosphate is recognized as important for future generations. Phosphorus is a basic component of life like nitrogen, but, unlike nitrogen, phosphorus does not have a cycle to constantly replenish its supply. It is very likely that the use of phytase will expand as the need to conserve the world's phosphate reserves increases. |
Does hyperflex total knee design improve postoperative active flexion?
The rotating platform flexion (RPF) Sigma total knee prosthesis (DePuy; Warsaw, Indiana) was designed for maintaining the contact of the condyles with their corresponding tibial plateau throughout the high-flexion range. However, this requires an additional 3-mm bone cut of the posterior condyles. Compared to the conventional design, this modification is intended to improve the flexion range. This hypothesis was tested by studying the increase in flexion (flexion gain, range of motion [ROM], active flexion) of 59 consecutive patients who had received the hyperflex design implant (RPF), whose preoperative mobility values were retrospectively compared to these same values in another 59 consecutive matched patients who had received an implant with the conventional design of the same implant (rotating platform [RP]) between June 2005 and June 2006. Postoperative mobility was measured visually with a goniometer. Only osteoarthritic knees were eligible to be included. Knees with more than 20 degrees flexion contracture or less than 90 degrees flexion, and patients with a body mass index (BMI) greater than 30 were excluded. Both groups were comparable with regard to age, preoperative mobility values, and BMI. The sex ratio differed significantly, but preoperative mobility did not differ significantly in male and female patients in the RP and in the RPF groups. The difference in sex ratio did not appear to be a bias influencing preoperative mobility. Overall, the flexion gain was correlated to preoperative flexion (r=-0.75, p<0.001). The flexion gain in the RPF group was significantly greater than in the RP group (13+-20 versus 6+-13; p=0.02) as was the ROM gain (10+/-17 degrees versus 4+/-12 degrees; p=0.02). However, the one-year active mean flexions were not significantly different (118+/-14 degrees versus 116+/-6 degrees; p=0.47). In patients whose preoperative flexion was less than 120 degrees (18 and 27 RPF prostheses), the flexion and ROM gains were significantly greater in the RPF group (23+/-16 degrees versus 14+/-16 degrees; p=0.03 and 26+/-18 degrees versus 17+/-9 degrees; p=0.05), and the mean one-year active flexion was also greater in the RPF group (124+/-13 degrees versus 116+/-8 degrees, p=0.02). In patients with more than 120 degrees of preoperative flexion, the flexion and ROM gains and the final mean flexions in both groups were comparable. In particular, there were nine patients in the RP group and ten patients in the RPF group whose flexion decreased. Thus, the Sigma RPF prosthesis provided a significant additional flexion gain in patients with 90-120 degrees preoperative flexion, and less than 20 degrees flexion contracture. Patients with a preoperative flexion greater than 120 degrees were exposed to a decrease in flexion range whichever implant was used, RP or RPF. Level 3, therapeutic study. |
Cyclic nucleotides regulate the activity of L-type calcium channels in smooth muscle cells from rat portal vein.
In order to advance our previous findings that the macroscopic slow Ca2+ currents of vascular smooth muscle (VSM) cells are regulated by cyclic nucleotides, the effects of cAMP and cGMP on the activity of single slow (L-type) Ca2+ channels were investigated using cell-attached patch clamp (22-25 degrees C). Freshly isolated VSM cells were obtained from adult male rat portal vein. For the single-channel recordings, the pipette was filled with a solution containing 90 mM Ba2+ and 1 microM Bay-K-8644 solution, and the bath contained 140 mM KCl to "zero" the membrane potential. Depolarizing pulses to 0 mV, from a holding potential (HP) of -80 mV, elicited inward unitary currents. The activity of these channels was completely blocked by superfusion of 10 microM nifedipine. Extracellular perfusion of the single cells with membrane-permeable cGMP and cAMP analogs (8Br-cGMP and 8Br-cAMP) at 1 mM caused a slight inhibition, but higher doses (3 mM), clearly showed an inhibitory effect on the single-channel activity. cAMP (100 microM) stimulated one out of five patches tested, and 100 microM cGMP showed no effect in three patches tested. Compared with control, both cyclic nucleotides at 3 mM decreased the ensemble-averaged currents by 26.7 +/- 4.1% and 37.3 +/- 2.1%, respectively. Unit amplitude and slope conductance were not changed. The normal conductance of the Ca2+ channel was 20.8 +/- 0.04 pS (n = 9), and the conductances in the presence of cAMP (n = 5) and cGMP (n = 6) were 19.3 +/- 0.04 and 20.5 +/- 0.05 pS, respectively. Single-channel kinetic analysis showed that cAMP did not affect the mean open-time, and cGMP slightly decreased the mean open-time. However, both cAMP and cGMP increased the mean closed-time. In addition, cAMP decreased the open probability (NPo) by a factor of 1.7, from 0.26 +/- 0.04 to 0.15 +/- 0.03 (P < 0.05, Student's t-test) and cGMP decreased NPo by a factor of 2.5, from 0.24 +/- 0.08 to 0.10 +/- 0.02 (P < 0.05). H-7, a non-specific protein kinase inhibitor, prevented the inhibitory effects of both cAMP and cGMP on the activity of single Ca2+ channels in rat portal vein cells. The results demonstrate that both cAMP and cGMP inhibit L-type Ca2+ channel activities in VSM cells from rat portal vein. This inhibition may be mediated by the cAMP and cGMP-dependent protein kinase phosphorylation of the L-type Ca2+ channels (or an associated regulatory protein). |
Ovarian Suppression With Triptorelin During Adjuvant Breast Cancer Chemotherapy and Long-term Ovarian Function, Pregnancies, and Disease-Free Survival: A Randomized Clinical Trial.
Whether the administration of luteinizing hormone-releasing hormone analogues (LHRHa) during chemotherapy is a reliable strategy to preserve ovarian function is controversial owing to both the lack of data on long-term ovarian function and pregnancies and the safety concerns about the potential negative interactions between endocrine therapy and chemotherapy. To evaluate long-term results of LHRHa-induced ovarian suppression during breast cancer chemotherapy. Parallel, randomized, open-label, phase 3 superiority trial conducted at 16 Italian sites. Between October 2003 and January 2008, 281 premenopausal women with stage I to III hormone receptor-positive or hormone receptor-negative breast cancer were enrolled. Last annual follow-up was June 3, 2014. Patients were randomized to receive adjuvant or neoadjuvant chemotherapy alone (control group) or chemotherapy plus triptorelin (LHRHa group). The primary planned end point was incidence of chemotherapy-induced early menopause. Post hoc end points were long-term ovarian function (evaluated by yearly assessment of menstrual activity and defined as resumed by the occurrence of at least 1 menstrual cycle), pregnancies, and disease-free survival (DFS). A total of 281 women (median age, 39 [range, 24-45] years) were randomized. Median follow-up was 7.3 years (interquartile range, 6.3-8.2 years). The 5-year cumulative incidence estimate of menstrual resumption was 72.6% (95% CI, 65.7%-80.3%) among the 148 patients in the LHRHa group and 64.0% (95% CI, 56.2%-72.8%) among the 133 patients in the control group (hazard ratio [HR], 1.28 [95% CI, 0.98-1.68]; P = .07; age-adjusted HR, 1.48 [95% CI, 1.12-1.95]; P = .006). Eight pregnancies (5-year cumulative incidence estimate of pregnancy, 2.1% [95% CI, 0.7%-6.3%]) occurred in the LHRHa group and 3 (5-year cumulative incidence estimate of pregnancy, 1.6% [95% CI, 0.4%-6.2%]) in the control group (HR, 2.56 [95% CI, 0.68-9.60]; P = .14; age-adjusted HR, 2.40 [95% CI, 0.62-9.22]; P = .20). Five-year DFS was 80.5% (95% CI, 73.1%-86.1%) in the LHRHa group and 83.7% (95% CI, 76.1%-89.1%) in the control group (LHRHa vs control: HR, 1.17 [95% CI, 0.72-1.92]; P = .52). Among premenopausal women with either hormone receptor-positive or hormone receptor-negative breast cancer, concurrent administration of triptorelin and chemotherapy, compared with chemotherapy alone, was associated with higher long-term probability of ovarian function recovery, without a statistically significant difference in pregnancy rate. There was no statistically significant difference in DFS for women assigned to triptorelin and those assigned to chemotherapy alone, although study power was limited. clinicaltrials.gov Identifier:NCT00311636. |
Dissociation of antiproliferative and antihormonal effects of the somatostatin analog octreotide on 7315b pituitary tumor cells.
The somatostatin (SS) analog octreotide has been successfully used in the treatment of (neuro)endocrine tumors. The mechanism of action of the tumor (growth) inhibitory action by octreotide is not fully understood. We have investigated the effect of octreotide on 7315b rat pituitary tumor cell growth, PRL release, and intracellular PRL concentrations in vitro. When cultured in medium with 10% fetal calf serum, the number of high affinity SS receptors increased with increasing culture time. On days 7, 14, and 21 of culture, the number of SS receptors amounted to 978 +/- 217, 3588 +/- 705, and 5865 +/- 3332 fmol/mg protein, respectively, whereas they were not measurable on day 0. From days 0-7, 7-14, and 14-21 of culture, octreotide (1 pM to 1 microM) inhibited PRL release and the intracellular PRL concentration, with IC50 values in the nanomolar range. However, no inhibition of cell growth was observed by these octreotide concentrations from day 0-7 of culture, while octreotide inhibited cell growth in a dose-dependent fashion from days 7-14 and 14-21 of culture (maximal inhibition by 25% and 26%, respectively). In a series of nine consecutive experiments we found a significant positive correlation between the percent inhibition of cell growth induced by 1 microM octreotide and the number of SS receptors on 7315b cells (r = 0.7865; P = 0.012). Inhibition of PRL release did not correlate with SS receptor numbers. Octreotide (1 microM) inhibited forskolin (0.5 microM)-stimulated cell growth and intracellular PRL concentrations, while in the presence of a high concentration of forskolin (10 microM), octreotide had no effect on forskolin-stimulated cell growth and intracellular PRL concentrations. In addition, its PRL release inhibitory effect was significantly lower in forskolin-stimulated cultures. Pretreatment of the cells with pertussis toxin (10 micrograms/liter) completely prevented the inhibition of cell growth by octreotide and diminished the inhibitory effect of octreotide on PRL release. Finally, 1 microM octreotide significantly inhibited forskolin-stimulated cAMP production (by 29% and 53% on days 7 and 14 of culture, respectively). We conclude that 1) octreotide inhibits 7315b rat pituitary tumor cell proliferation via a pertussis toxin-sensitive GTP-binding protein- and adenylate cyclase-dependent mechanism; and 2) the number of SS receptors on 7315b pituitary tumor cells may determine whether octreotide exerts a direct antiproliferative effect, whereas its antihormonal effect occurs in the presence of relatively low numbers of SS receptors. This suggests a dissociation of the antiproliferative and antihormonal effects induced by octreotide. |