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11.
BACKGROUND: Tumor necrosis factor related apoptosis-inducing ligand/Apo2 ligand (TRAIL/Apo-2L) is a novel anticancer agent, capable of inducing apoptosis preferentially in tumor and transformed cells. TRAIL-R1/death receptor (DR)4 and TRAIL-R2/DR5 are members of the tumor necrosis factor (TNF) receptor family, and can be activated by the TRAIL. We examined the clinical potential of chemotherapeutic drugs and TRAIL for the treatment of prostate cancer. METHODS: Prostate and bladder cancer cells were exposed to chemotherapeutic drugs (paclitaxel, vincristine, vinblastine, etoposide, doxorubicin, and camptothecin) and TRAIL. Cell viability was measured by sodium 3'[1-(phenylaminocarbonyl)-3,4-tetrazolium]-bis (4-methoxy-6-nitro) assay; expressions of death receptors and Bcl-2 family members were measured by Western blotting, ELISA and ribonuclease protection assay. PC-3 tumor cells xenografted athymic nude mice were exposed to chemotherapeutic drugs and TRAIL, either alone or in combination, to measure tumor growth and survival of mice. Apoptosis was measured by annexin V-FITC/propidium iodide staining, and terminal deoxynucleotidyltransferase-mediated nick end labeling assay. Caspase-3 activity was measured by the Western blotting and immunohistochemistry. RESULTS: TRAIL induced apoptosis with varying sensitivity. Chemotherapeutic drugs (paclitaxel, vincristine, vinblastine, etoposide, doxorubicin, and camptothecin) significantly augmented TRAIL-induced apoptosis in cancer cells through up-regulation of DR4, DR5, Bax, and Bak, and induction of caspase activation. Mitochondrial pathway enhanced the synergistic interactions between drugs and TRAIL. The sequential treatment of mice with chemotherapeutic drugs followed by TRAIL induced caspase-3 activity, and apoptosis, inhibited angiogenesis, completely eradicated the established tumors, and enhanced survival of mice. CONCLUSIONS: Chemotherapeutic drugs can be used to enhance the therapeutic potential of TRAIL in prostate cancer.  相似文献   
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Congenital hypofibrinogenemia is a rare bleeding disorder characterized by abnormally low levels of fibrinogen in plasma, generally due to heterozygous mutations in one of the three fibrinogen genes (FGA, FGB, and FGG, coding for Aα, Bβ, and γ chain, respectively). Hypofibrinogenemic patients are usually asymptomatic, whereas individuals bearing similar mutations in the homozygous or compound heterozygous state develop a severe bleeding disorder: afibrinogenemia. The mutational spectrum of these quantitative fibrinogen disorders includes large deletions, point mutations causing premature termination codons, and missense mutations affecting fibrinogen assembly or secretion, distributed throughout the 50-kb fibrinogen gene cluster. In this study, we report the mutational screening of two unrelated hypofibrinogenemic patients leading to the identification of two missense mutations, one hitherto unknown (αCys45Phe), and one previously described (γAsn345Ser). The involvement of αCys45Phe and γAsn345Ser in the pathogenesis of hypofibrinogenemia was investigated by in-vitro expression experiments. Both mutations were demonstrated to cause a severe impairment of intracellular fibrinogen processing, either by affecting half-molecule dimerization (αCys45Phe) or by hampering hexamer secretion (γAsn345Ser).  相似文献   
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Chorea is a neurological adverse effect of oral contraceptive pills (OCPs). The onset of chorea following OCPs usage varies widely from few weeks to several years. We report a rare case of chorea which developed within a week of starting OCPs in an adolescent girl with polycystic ovarian disease.KEY WORDS: Chorea, oral contraceptive pills, polycystic ovarian disease  相似文献   
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Pediatric epilepsy comprises chronic neurological disorders characterized by recurrent seizures. Sodium valproate is one of the common antiseizure medications used for treatment. Glucuronide conjugation is the major metabolic pathway of sodium valproate, carried out by the enzyme uridine 5′-diphosphate (UDP) glucuronosyl transferase (UGT) whose gene polymorphisms may alter the clinical outcome. The objective of this study was to assess the association between UGT1A6 genetic polymorphism and clinical outcome in terms of efficacy and tolerability in pediatric epileptic patients on sodium valproate monotherapy. Pediatric epileptic patients (n=65) aged 2-18 years receiving sodium valproate monotherapy for the past one month were included. Genetic polymorphism patterns of UGT1A6 (T19G, A541G, A552C) were evaluated by PCR-RFLP. Clinical outcome was seizure control during the 6 months observation period. Tolerability was measured by estimating the hepatic, renal, and other lab parameters. Out of 65 patients, TT (40%), TG (57%), and GG (3%) patterns were observed in UGT1A6 (T19G) gene, AA (51%), AG (40%), and GG (9%) in (A541G) gene, and AA (43%), AC (43%), and CC (14%) in (A552C) gene. No statistical difference in clinical outcome was found for different UGT1A6 genetic polymorphism patterns. We concluded that different patterns of UGT1A6 genetic polymorphism were not associated with the clinical outcome of sodium valproate in terms of efficacy and tolerability. Sodium valproate was well-tolerated among pediatric patients with epilepsy and can be used as an effective antiseizure medication.  相似文献   
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To identify radiographic and MR features of hip osteoarthritis (OA) related to reduced hip extension during walking. Sixty six subjects, were stratified into those with (n = 36, KL = 2, 3) and without (n = 30, KL = 0, 1) radiographic hip OA. Cartilage and labrum lesions were graded semi‐quantitatively on hip MRI. Alpha angle and lateral center edge (LCE) angle were measured. Sagittal kinematics and kinetics were calculated during walking at speed of 1.35 m/s using 3‐D motion capture. All subjects completed Hip disability and Osteoarthritis Outcome Score (HOOS), timed up and go, and 6 min walk tests. Variables were compared between the two groups using one‐way ANOVA (adjusting for age). Correlations of radiographic and MR parameters with peak hip extension were calculated. The OA group was older, had greater pain, and limitation of function. They also had lower peak hip extension and higher peak hip flexion; and worse acetabular and femoral cartilage lesions. Peak hip extension and flexion correlated with KL grade, cartilage lesions in the inferior and posterior femur. Reduced hip extension and greater hip flexion during walking are present in high functioning (HOOS > 85%) individuals with mild‐moderate hip OA, and are associated with cartilage lesions. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:527–534, 2015.  相似文献   
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Purpose:The purpose of this study is to compare the endothelial cell loss (ECL) in nanophthalmic eyes and age-matched controls undergoing cataract surgery by phacoemulsification and also to identify the risk factors influencing the endothelial cell density (ECD). This was a prospective comparative interventional case series.Methods:We enrolled 19 nanophthalmic eyes (study group) and 42 age-matched cataract controls (control group) undergoing phacoemulsification after meeting the inclusion criteria. Ocular parameters like best-corrected visual acuity, intraocular pressure, pachymetry, specular microscopy, and slit lamp findings were noted preoperatively and at month 1 and 3 postsurgery. All nanophthalmic eyes underwent cataract surgery with concomitant prophylactic posterior sclerostomy.Results:The median percentage endothelial loss in nanophthalmic eyes was 4.0 (IQR 0–23.5), 7.4 (IQR 1.0–-22.4) at 1 and 3 months postoperatively compared to 6.3 (IQR 1.7–14.1) and 6.4 (IQR 2.6–-12.1) in age controlled normal eyes (P = 0.94, P = 0.46, respectively). Linear regression analysis showed increasing age as the only variable influencing the percentage decrease in corneal ECD in the study group (P = 0.001). Nanophthalmic eyes with ACD <2.5 mm had a significantly greater reduction in ECD at 3 months postcataract surgery compared to baseline (P = 0.039). Visual outcomes and IOP reduction in the study group with ACD >2.5 mm were significantly better postcataract surgery (P = 0.02 and P = 0.002, respectively).Conclusion:The percentage of ECL in nanophthalmic eyes undergoing phacoemulsification is equivalent to normal eyes. However, in the nanophthamic eyes with AC depth <2.5 mm, the percentage cell loss was significantly higher warranting the need for extensive intraoperative care. Increasing age was found to be the only significant risk factor influencing the ECD in short eyes.  相似文献   
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High‐resolution peripheral quantitative computed tomography (HR‐pQCT) has recently been introduced as a clinical research tool for in vivo assessment of bone quality. The utility of this technology to address important skeletal health questions requires translation to standardized multicenter data pools. Our goal was to evaluate the feasibility of pooling data in multicenter HR‐pQCT imaging trials. Reproducibility imaging experiments were performed using structure and composition‐realistic phantoms constructed from cadaveric radii. Single‐center precision was determined by repeat scanning over short‐term (<72 hours), intermediate‐term (3–5 months), and long‐term intervals (28 months). Multicenter precision was determined by imaging the phantoms at nine different HR‐pQCT centers. Least significant change (LSC) and root mean squared coefficient of variation (RMSCV) for each interval and across centers was calculated for bone density, geometry, microstructure, and biomechanical parameters. Single‐center short‐term RMSCVs were <1% for all parameters except cortical thickness (Ct.Th) (1.1%), spatial variability in cortical thickness (Ct.Th.SD) (2.6%), standard deviation of trabecular separation (Tb.Sp.SD) (1.8%), and porosity measures (6% to 8%). Intermediate‐term RMSCVs were generally not statistically different from short‐term values. Long‐term variability was significantly greater for all density measures (0.7% to 2.0%; p < 0.05 versus short‐term) and several structure measures: cortical thickness (Ct.Th) (3.4%; p < 0.01 versus short‐term), cortical porosity (Ct.Po) (15.4%; p < 0.01 versus short‐term), and trabecular thickness (Tb.Th) (2.2%; p < 0.01 versus short‐term). Multicenter RMSCVs were also significantly higher than short‐term values: 2% to 4% for density and micro–finite element analysis (µFE) measures (p < 0.0001), 2.6% to 5.3% for morphometric measures (p < 0.001), whereas Ct.Po was 16.2% (p < 0.001). In the absence of subject motion, multicenter precision errors for HR‐pQCT parameters were generally less than 5%. Phantom‐based multicenter precision was comparable to previously reported in in vivo single‐center precision errors, although this was approximately two to five times worse than ex vivo short‐term precision. The data generated from this study will contribute to the future design and validation of standardized procedures that are broadly translatable to multicenter study designs. © 2013 American Society for Bone and Mineral Research.  相似文献   
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