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1.
The disintegrin and metalloproteinase 10 (ADAM10) is a membrane‐anchored metalloproteinase with both proteolytic and disintegrin characteristics. Here, we investigate the expression, regulation, and functional role of ADAM10 in axonal outgrowth and myelination of the peripheral nerve. Expression pattern analysis of 11 ADAM family members in co‐cultures of rat dorsal root ganglia (DRG) neurons and Schwann cells (SCs) demonstrated the most pronounced mRNA expression for ADAM10. In further studies, ADAM10 was found to be consistently upregulated in DRG‐SC co‐cultures before the induction of myelination. Neurons as well as SCs widely expressed ADAM10 at the protein level. In neurons, the expression of ADAM10 was exclusively limited to the axons before the induction of myelination. Inhibition of ADAM10 activity by the hydroxamate‐based inhibitors GI254023X and GW280264X resulted in a significant decrease in the mean axonal length. These data suggest that ADAM10 represents a prerequisite for myelination, although its activity is not required during the process of myelination itself as demonstrated by expression analysis of myelin protein zero (P0) and Sudan black staining. Hence, during the process of myelin formation, ADAM10 is highly upregulated and appears to be critically involved in axonal outgrowth that is a requirement for myelination in the peripheral nerve. © 2009 Wiley‐Liss, Inc.  相似文献   
2.
目的 总结、分析150例电视胸腔镜心血管外科手术的临床结果。方法 应用电视胸腔镜手术技术对动脉导管未闭、房间隔缺损、室间隔缺损、三尖辨关闭不全、冠状动脉-肺动脉瘘、心包积液、原发性长Q-T综合征、雷诺病,心包囊肿等进行治疗。结果 动脉导管未闭均成功在胸腔镜下钳闭;房缺、室缺在胸腔镜体外循环下进行补片修补,冠状动脉瘘胸腔镜下修补;心包积液进行心包活检与开窗引流;长Q-T综合征进行胸腔镜下左T2、T3胸交感神经节切除,均无严重并发症,术后患者恢复良好。结论 电视胸腔镜心血管外科手术可取得满意的临床治疗结果。  相似文献   
3.
Amyotrophic lateral sclerosis (ALS) is a paralytic disorder characterized by degeneration of large motor neurons of the brain and spinal cord. A subset of ALS is inherited (familial ALS, FALS) and is associated with more than 70 different mutations in the SOD1 gene. Here we report that lymphoblast cell lines derived from FALS patients with 16 different mutations in SOD1 gene exhibit significant increase of intracellular reactive oxygen species (ROS) compared with sporadic ALS (SALS) and normal controls (spouses of ALS patients). The ROS generation did not correlate with SOD1 activity. Further, cells incubated with vitamin C, catalase or the flavinoid quercetin significantly reduced ROS in all groups. The catalase inhibitor 3-amino-1,2,4-triazole resulted in a ten-fold increase of ROS in all groups. Neither L-nitroarginine, a nitric oxide synthase inhibitor or vitamin E altered the ROS levels. Thus, these studies suggest that hydrogen peroxide (H(2)O(2)) is a major ROS elevated in FALS lymphoblasts and it may contribute to the degeneration of susceptible cells. Further, we postulate a mechanism by which increased H(2)O(2) could be generated by mutant SOD1.  相似文献   
4.
BACKGROUND: Entamoeba histolytica forms cyst-like structures (CLS) in PEHPS but not in TYS-33 medium. Sodium dodecyl sulfate [(SDS (0.1%)] dissolves most of them in 10 min, but not natural cysts. Chitin is responsible mainly for cyst wall resistance. Its synthesis depends on Mg(2)+, Mn(2)+, or Co(2)+, whose action is interactive. With the aid of the Simplex method, we analyzed the effect of 20 blends of these cations to find the one that, when added to PEHPS, produced the highest proportion of CLS resistant to 1% SDS (RCLS). METHODS: The concentration of Mg(2)+, Mn(2)+, and Co(2)+ was determined in PEHPS and TYI-S-33 with a flame atomic absorption spectrometer. The proportion of RCLS produced in PEHPS with each ion blend was tested. The CLS and RCLS affinity to fluorescein wheat germ agglutinin (WGA/FITC), which binds chitin, was determined. RESULTS: PEHPS contained a similar concentration of Co(2)+ (0.52 microM) and 3.4 and 1.6 times more Mg(2)+ (798 microM) and Mn(2)+ (3.15 microM) than TYI-S-33, respectively. The proportion of RCLS increased gradually in PEHPS until reaching 3.6 +/- 1.43% with MgCl(2) 1.22 mM, MnCl(2) 14.44 mM, and CoCl(2) 19.44 mM (ion blend No. 20). Both CLS and RCLS bound WGA/FITC. The RCLS formed in the presence of ion blend No. 20 appeared wrinkled. CONCLUSIONS: Mg(2)+, Mn(2)+, and Co(2)+ enhanced the ability of PEHPS to form RCLS, possibly because these ions stimulated their chitin synthesis. Although ion blend No. 20 produced the highest proportion of RCLS, this high ion concentration may be toxic for encysting amebas.  相似文献   
5.
L-carnitine is assumed to play an important role in fetal development, and there is evidence that carnitine is transported across the placenta. The protein involved in this transfer, however, has not been identified on a molecular level. We therefore characterized localization and function of the carnitine transporter OCTN2 in human placenta. Significant expression of OCTN2 mRNA was detected in human placenta applying real-time polymerase chain reaction technology. Confocal immunofluorescence microscopy using an antibody directed against the carboxy terminus of OCTN2 protein revealed that it is predominantly expressed in the apical membrane of syncytiotrophoblasts. This was confirmed by the costaining of organic anion-transporting polypeptide B and MRP2, which are known to be expressed mainly in the basal and apical syncytiotrophoblasts membrane, respectively. To further support this finding, we performed transport studies using basal and apical placenta membrane vesicles. We could demonstrate that the carnitine uptake into the apical vesicles was about eight times higher compared with the basal ones. Moreover, this uptake was sodium- and pH-dependent with an apparent K(m) value of 21 muM and inhibited by verapamil, which is in line with published data for recombinant OCTN2. Finally, experiments using trophoblasts in cell culture revealed that expression of OCTN2 paralleled human choriogonadotropin production and thus is modulated by cellular differentiation. In summary, we show expression and function of OCTN2 in human placenta. Moreover, several lines of evidence indicate that OCTN2 is localized in the apical membrane of syncytiotrophoblasts, thereby suggesting a major role in the uptake of carnitine during fetal development.  相似文献   
6.
目的 对医疗机构中药制剂创新和持续发展能力进行综合评价,为行政管理部门决策及各医院中药制剂可持续发展提供参考。方法 以浙江省133家医疗机构中药制剂调研数据为对象,利用层次分析法构建医疗机构中药制剂创新和持续发展能力评价体系,通过反向传播神经网络构建中药制剂室/中心评价体系预测模型。结果 构建的医疗机构中药制剂创新和持续发展能力评价指标体系包含4项二级指标以及19项三级指标,其中研发品种数、超百万品种数、注册品种数、研发方式、制剂室面积指标的权重值较高,分别为 0.15758、0.12928、0.09343、0.07879和0.07458。熵权法结合层次分析法的指标权重构建反向传播神经网络,Levenberg-Marquardt算法和Scaled Conjugate Gradient算法训练模型总体相关系数分别为0.98983和0.9348。结论 本研究构建了一个科学有效的医疗机构中药制剂创新和持续发展能力综合评价体系,可实现对医疗机构中药制剂综合能力的预测评价。  相似文献   
7.
目的:观察加味半夏白术天麻汤治疗风痰阻络型脑梗塞的临床疗效及对血液流变学、血清超敏C反应蛋白(he—CRP)的影响。方法:对照组给予阿斯匹林片0.1g,日1次;胞二磷胆碱0.5g加入生理盐水100ml中静脉点滴,日1次;脑水肿明显者应用甘露醇脱水治疗。治疗组在对照组基础上加用半夏白术天麻汤加味。连续治疗一个月后进行临床疗效及神经功能的评定,治疗前后检查血液流变学及he—CRP。结果:治疗组总有效率95%,对照组81.67%,治疗组优于对照组,有显著差异(P〈0.05);在改善神经功能评分、血液流变学及he—CRP方面,治疗组均优于对照组,有显著性差异(P〈0.05,或P〈0.01)。结论:加味半夏白术天麻汤治疗风痰阻络型脑梗塞临床疗效较好,并能减少神经功能缺损程度评分,改善血液流变学及降低he—CRP。  相似文献   
8.
In patients with coronary artery disease (CAD), coronary blood flow is usually impaired due to imbalanced vasoactive substances such as nitric oxide (NO) and endothelin-1 (ET-1). The study was designed to test the effects of Ginkgo biloba extract (GBE) on the distal left anterior descending coronary artery (LAD) blood flow and plasma NO and ET-1 levels. Eighty CAD patients were randomly assigned to GBE (n = 42) and control (n = 38) groups. The LAD blood flow was assessed non-invasively using Doppler echocardiography at baseline and after 2 weeks. GBE treatment demonstrated a significant improvement in maximal diastolic peak velocity (MDPV), maximal systolic peak velocity (MSPV) and diastolic time velocity integral (DTVI) compared with controls (14.61 +/- 4.51% vs 0.67 +/- 2.66%, 9.03 +/- 4.81% vs 0.34 +/- 2.67% and 14.69 +/- 5.08% vs 0.68 +/- 3.00%, respectively, p < 0.01). NO was increased by 12.42% (p < 0.01), whereas ET-1 was decreased by 5.82% (p < 0.01). The NO/ET-1 ratio was increased by 19.47% (p < 0.01). A linear correlation was confirmed between the percentage change in LAD blood flow and in NO, ET-1 or NO/ET-1 ratio following GBE treatment. The results suggest that GBE treatment in CAD patients led to an increase of LAD blood flow, which might at least be related partly to the restoration of the delicate equilibrium between NO and ET-1.  相似文献   
9.
Plants belonging to the genus Opuntia spp. are the most abundant of the Cactaceae family, grown throughout America and the Mediterranean central area. Its fruit, known as cactus pear or prickly pear, is an oval berry grouped in different colors. Some studies have shown its antioxidant activities which may help in preventing chronic pathologies such as diabetes. The purpose of the study was to evaluate the antioxidant capacity of three varieties of prickly pear juice (red-purple, white-green and yellow-orange) in five different concentrations (100, 250, 500, 750, and 1000 mg/mL) by DPPH (1,1-diphenyl-2-picrylhydrazyl radical) colorimetric method, selecting the best variety to determine its anticlastogenic potential against methyl methanesulfonate (MMS). The results indicate that the highest antioxidant was found in the juice of the prickly pear red-purple variety (PPRP), in all concentrations. Its anticlastogenic potential was therefore evaluated with a micronucleus assay. The experiment was run over two weeks. A negative control was included along with a positive control with MMS (40 mg/kg), a group of mice treated with PPRP (25 mL/kg), and three groups with PPRP (in doses of 25, 16.5 and 8.3 mL/kg) plus the mutagen. The PPRP was administered daily by oral gavage and the MMS was injected intraperitoneally five days prior to the end of the experiment. Blood samples were obtained at 0, 24, 48, 72 and 96 h in order to determine the frequency of micronucleated polychromatic erythrocytes (MNPE). The results indicated that PPRP is not a genotoxic agent, on the contrary, it may reduce the number of MNPE. In this regard, the PPRP showed an anticlastogenic effect directly proportional to its concentrations. Thus, the highest protection was obtained with a concentration of 25 mL/kg after 48 h of treatment.  相似文献   
10.
目的分析全髋关节置换术后脱位的影响因素,探讨术中如何准确置人髋关节假体以减少髋关节脱位。方法分析我科2005年1月—2012年12月全髋关节置换术后脱位病例的影响因素。结果本组病人脱位发生率为1.3%。女性占脱位人数的比例为62%,男性占38%。早期脱位占脱位人数的比例为90%,晚期脱位占10%。前方脱位占脱位人数的比例为19%,后方脱位占81%。假体位置不良占脱位人数的比例为52%,精神神经功能不全者占29%,术后活动范围过度者占脱位人数的比例为19%。结论患者因素、术者因素及髋关节假体因素都对人工髋关节置换术后脱位产生影响,术中准确置人髋关节假体是影响髋关节脱位的关键因素。  相似文献   
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