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61.
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Purpose

Design short hairpin RNA (shRNA) interference sequence to silence glutathione S-transferase P1 (GSTP1) gene of androgen-independent prostate cancer cell line DU145, and then to explore its effect on sensitivity to chemotherapeutics.

Methods

Target sequence was picked up to form the shRNA. DU145 cell was divided into five groups according to the shRNA added for transfection: shRNA255, shRNA554, shRNA593, negative-shRNA and blank group. Fluorescence microscope was used to pick up the shRNA with the highest transfection ratio. Western blotting and RT-PCR were taken to pick up the shRNA with the best gene silencing result. 3-(4,5-Dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide assay and terminal de-oxynucleotidyl transferase-mediated dUTP nick end-labeling assay were used to detect survival ratio and apoptosis ratio of DU145 administered of fluorouracil (5-FU) or paclitaxel (PA) at different concentrations before and after shRNA transfection.

Results

Three different shRNA oligonucleotides (shRNA255; shRNA554; shRNA593) targeting the coding sequence of GSTP1 mRNA and one negative control shRNA were constructed. The transfection ratio of shRNA554 (76.2 ± 0.68 %) was higher than that of shRNA255 (63.3 ± 1.04 %) (P < 0.01) or shRNA593 (72.7 ± 0.33 %) (P < 0.01). After transfection of shRNA554, the mRNA and protein of level were the lowest, P < 0.01. The survival ratio of DU145 administered with 5-FU of different concentrations (30, 60, 120, 240 μg/ml) declined after transfection (P < 0.01). Besides, the apoptosis ratio increased after transfection (P < 0.01). Similarly the survival ratio of DU145 administered with PA of different concentrations (0.2, 2, 10, 20 μg/ml) declined (P < 0.01) and the apoptosis ratio increased (P < 0.01) after transfection.

Conclusions

The gene GSTP1 silence via shRNA transfection to androgen-independent prostate cancer cell line DU145 enhances the sensitivity to chemotherapeutics.  相似文献   
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李亚军  谢鹏 《中国临床康复》2006,10(24):148-149
目的:分析癫痫患者发作期和发作间期自主神经功能障碍与癫痫患者突然意外死亡的关系。 资料来源:应用计算机检索Medline数据库1985-01/2004-12期间的相关文章限定文章语言种类为英文,检索词”epilepsy and autonomic”和“seizure and autonomic”。 资料选择:对资料进行初审,纳入标准:①癫痫和癫痫发作与自主神经功能状态关系。②癫痫突然意外死亡。 资料提炼:共收集到符合上述要求的文献45篇,排除27篇重复性内容。18篇符合纳入标准:其中16篇关于癫痫和癫痫发作与自主神经功能障碍,2篇关于自主神经功能障碍与癫痫患者突然意外死亡的关系。 资料综合:癫痫和癫痫发作均可引起心脏自主神经功能障碍,无论部分性发作还是全身性发作癫痫患者发作期和发作间期都存在自主神经功能障碍。而心脏自主神经功能障碍与心律失常尤其是恶性心律失常的发生密切相关。 结论:癫痫患者发作期和发作间期心脏自主神经功能障碍引发的恶性心率失常可能是癫痫患者发生突然意外死亡的重要原因。  相似文献   
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Our aim was to observe the effects of psychological stress on the structure of the temporomandibular joint (TMJ), and to evaluate the expression of matrix metallopeptidase-3 (MMP-3) and tissue inhibitor of metalloproteinase-3 (TIMP-3) in condylar chondrocytes in rats. The rats were divided into 3 groups of 12 according to the duration of psychological stress: 3 weeks or 6 weeks, and 6 weeks of recovery. A fourth group of 12 rats was used as controls. Each rat was evaluated by the open-field test and the weight measured. The results confirmed psychological stress in 24 of the 36 rats (67%). The tissues of the TMJ were stained with haematoxylin and eosin and pathological changes were studied under a light microscope. MMP-3 and TIMP-3 expression was investigated using the SP kit. The experimental groups showed thinning of articular cartilage, shedding of collagen fibres, cracks in the articular discs, and other structural changes that were aggravated with time, from three weeks to six weeks. The 6-week recovery group showed an improvement in these changes, which indicated the initiation of joint repair. The MMP-3 expression rate correlated with the degree of joint lesion, while the TIMP-3 rate showed an opposite trend and was highest in the 6-week recovery group. Our findings clearly indicate that psychological stress may play an important part in the development of TMJ diseases in rats; further studies should be made to extrapolate the results to other models before clinical use.  相似文献   
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69.

Purpose

To evaluate the effectiveness and safety of endoscopic carpal tunnel release (ECTR) and open carpal tunnel release (OCTR) using a meta-analysis of data from randomized controlled trials.

Materials and methods

Electronic searches of the Cochrane Register of Controlled Trials (CENTRAL, Issue 11 of 12, Nov 2012), PUBMED (1980 to Dec 2012), and EMBASE (1980 to Dec 2012) were used to identify randomized controlled trials that evaluated endoscopic vs open methods for treatment of carpal tunnel syndrome. Studies to be used were independently identified by two researchers. The methodological quality of the studies was assessed by the Cochrane Collaboration tool for assessing risk of bias.

Results

Fifteen randomized controlled trials involving 1,596 hands were included. Based on the Cochrane Collaboration tool for assessing risk of bias, four studies were rated as high quality, five studies were rated as moderate quality, and six were rated as low quality. Our meta-analysis indicated that ECTR resulted in better recovery of pinch strength, earlier time of return to work, but a higher rate of reversible nerve problems (including neurapraxia and numbness) than OCTR. ECTR also resulted in a lower rate of irreversible nerve damage (P > 0.05), wound problems (including wound infection, wound hematoma and wound dehiscence) and reflex sympathetic dystrophy (P > 0.05) compared with OCTR. Our meta-analysis revealed no obvious statistical differences in relief of symptoms (pain and paraesthesia), recovery of grip strength and reoperation rate.

Conclusion

Our meta-analysis of available randomized controlled trials demonstrated that ECTR and OCTR were similar in relief of symptoms, but ECTR resulted in better recovery of function and earlier return to work and was safer than OCTR.  相似文献   
70.
目的:研究小腿截肢患者站立状态下假肢对线对下肢受力特性的影响.方法:以假肢侧承重线和重力线作为评价指标,改变假肢矢状面和额状面的对线,采用激光测力平台测量患者静态站立时残侧承重线和重力线的位置,研究下肢受力状况的变化.结果:假肢侧承重线受踝关节对线的影响大于腿管对线调节的影响,并且力线随腿管与接受腔的前倾而前移,而额状面对线的影响很小;矢状面内重力线主要受踝关节对线调节的影响,并且与变化角近似正比例相关.结论:矢状面假肢对线调整对残侧下肢受力状况的影响较大,而额状面的对线调整影响较小.  相似文献   
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