miR-186 Represses Proliferation,Migration, Invasion,and EMT of Hepatocellular Carcinoma via Directly Targeting CDK6

The present study aimed to investigate the effect of miR-186 on proliferation, migration, invasion, and epithelial–mesenchymal transition (EMT) of hepatocellular carcinoma (HCC). In this work, miR-186 was downregulated in HCC tissues and cells, and low miR-186 level helped predict the occurrence of vascular invasion and poor prognosis in patients with HCC. miR-186 overexpression inhibited cell proliferation and tumor growth in nude mice, repressed migration and invasion abilities, and enhanced apoptosis in HCC cells. miR-186 also retarded progression of EMT. miR-186 directly bound to the 3 -untranslated regions of cyclin-dependent kinase 6 (CDK6) to inhibit its expression. Overexpression of CDK6 markedly reversed inhibitory effects of miR-186 on proliferation, apoptosis, migration, and invasion of HCC cells. Conversely, inhibition of CDK6 exerted synergic effect on the biological functions of miR-186. In conclusion, miR-186 represses proliferation, migration, invasion, and EMT, and induces apoptosis through targeting CDK6 in HCC, which may provide a new therapeutic target for HCC.     

兔颈动脉无缝线胶黏吻合与传统缝线吻合的对比研究

目的　对比研究兔颈动脉无缝线胶黏吻合与传统缝线吻合的手术操作情况和吻合口通畅情况。方法　将 16只新西兰大白兔随机分为对照组和实验组 ,记录每个吻合口的吻合时间及出血量 ,术后 1、2、4、12周分别取材观察其通畅情况 ,并对吻合口内膜增生情况行病理切片和计算机图像分析。结果　与对照组相比 ,实验组的手术时间明显缩短 [(8.19± 6.5 1)min比 (2 0 .5 0± 14 .3 5 )min] ,术中出血量明显减少 [(2 .44± 5 .83 )ml比 (10 .3 8± 17.49)ml] ,通畅率也较高 (93 .8%比87.5 % ) ,内膜增生程度明显减轻 ,术后 1、2、4、12周时其内膜厚度分别降低了 3 1.4%、2 4.5 %、2 3 .9%和 3 1.9% (P <0 .0 1) ,其内膜面积分别降低了 3 6.2 %、2 9.1%、3 1.3 %和 40 .0 % (P <0 .0 1)。结论　中小血管的无缝线胶黏吻合较传统的缝线吻合操作省时省力 ,术中出血少 ,避免了缝针和缝线对血管吻合口处的透壁性损伤 ,消除了缝线等异物对管壁的持续性刺激所致的增生性反应 ,使吻合口处内膜增生减轻 ,吻合口通畅率提高。     

Design considerations and quantitative assessment for the development of percutaneous mitral valve stent

Percutaneous heart valve replacement is gaining popularity, as more positive reports of satisfactory early clinical experiences are published. However this technique is mostly used for the replacement of pulmonary and aortic valves and less often for the repair and replacement of atrioventricular valves mainly due to their anatomical complexity. While the challenges posed by the complexity of the mitral annulus anatomy cannot be mitigated, it is possible to design mitral stents that could offer good anchorage and support to the valve prosthesis. This paper describes four new Nitinol based mitral valve designs with specific features intended to address migration and paravalvular leaks associated with mitral valve designs. The paper also describes maximum possible crimpability assessment of these mitral stent designs using a crimpability index formulation based on the various stent design parameters. The actual crimpability of the designs was further evaluated using finite element analysis (FEA). Furthermore, fatigue modeling and analysis was also done on these designs. One of the models was then coated with polytetrafluoroethylene (PTFE) with leaflets sutured and put to: (i) leaflet functional tests to check for proper coaptation of the leaflet and regurgitation leakages on a phantom model and (ii) anchorage test where the stented valve was deployed in an explanted pig heart. Simulations results showed that all the stents designs could be crimped to 18F without mechanical failure. Leaflet functional test results showed that the valve leaflets in the fabricated stented valve coapted properly and the regurgitation leakage being within acceptable limits. Deployment of the stented valve in the explanted heart showed that it anchors well in the mitral annulus. Based on these promising results of the one design tested, the other stent models proposed here were also considered to be promising for percutaneous replacement of mitral valves for the treatment of mitral regurgitation, by virtue of their key features as well as effective crimping. These models will be fabricated and put to all the aforementioned tests before being taken for animal trials.     

血管内皮细胞生长因子与增殖细胞核抗原联合检测用于大肠癌临床预后判定

目的　探讨大肠癌血管内皮细胞生长因子 (VEGF)及增殖细胞核抗原 (PCNA)与大肠癌术后有无潜在性转移及复发的关系。方法　对 5 9例已获确诊的大肠癌石蜡标本作免疫组化SP法染色 ,检测其VEGF及PCNA的表达 ,并与 12例正常大肠组织和 16例大肠腺瘤进行比较。结果　大肠癌VEGF的表达明显高于大肠腺瘤 (P<0 .0 5 ) ;DukesA +B期大肠癌VEGF的表达与DukesC +D期比较 ,差异有显著性 (P<0 .0 5 ) ;术后复发组VEGF的表达明显高于无复发组 (P<0 .0 5 )。增殖活性表达提示 ,大肠癌分化程度越低 ,有淋巴结或肝转移时 ,其PCNA指数增高 ;术后有、无复发者之间 ,其PCNA指数差异有显著性 (P<0 .0 5 )。结论　大肠癌VEGF与PCNA的表达与肿瘤的浸润、转移密切相关。手术时虽然无明显转移灶 ,VEGF阳性及PCNA活性增强时仍可能有潜在的转移存在。     

静脉注射血管内皮细胞对异种心脏移植的影响

目的　探讨诱导非协调性异种移植免疫耐受的新方法。方法　移植前 1 4d外周静脉注射抗原量 1 0× 1 0 6 个豚鼠血管内皮细胞或联合腹腔注射环磷酰胺 (2 0mg·kg- 1 ·d- 1 × 1 4d)诱导豚鼠 大鼠异种心脏移植免疫耐受 ,观察供心存活时间。结果　外周静脉注射豚鼠血管内皮细胞联合使用环磷酰胺能够延长豚鼠 大鼠异种心脏移植存活时间 ,其平均存活时间为 (67.5± 6 .4)min ,与其余各组相比 ,差异有显著性 (P <0 .0 5)。供心标本免疫组织化学检测显示豚鼠血管内皮细胞外周静脉注射联合使用环磷酰胺组抗体IgM及补体C3沉积均较其余组少 ,定量测定分别为40 .5± 3 .9,46 .8± 5 .2 ,与其余各组相比 ,差异有显著性 (P <0 .0 5)。结论　移植术前外周静脉注射血管内皮细胞联合使用免疫抑制剂能够延长非协调性异种心脏移植存活时间 ,血管内皮细胞可以作为新的耐受原诱导免疫耐受     

基质金属蛋白酶组织抑制剂-2基因转染对平滑肌细胞的影响

目的探讨基质金属蛋白酶组织抑制剂(TIMP)2基因对体外培养大鼠主动脉平滑肌细胞(SMCs)增殖和迁移能力的影响。方法利用重组腺病毒载体,将目的基因导入宿主细胞,建立转基因细胞株。应用逆转录聚合酶链反应(RTPCR)和酶联吸附试验(ELISA)检测TIMP2表达。同时应用细胞直接计数法和侵袭小室研究转染细胞体外增殖和侵袭情况。结果转染TIMP2基因的平滑肌细胞基因组中存在有590bp目的基因特异性片断,TIMP2蛋白在转染后平滑肌细胞中获得稳定表达和分泌。转染后平滑肌细胞生长受到明显抑制。AdhTIMP2组透过人工基底膜的细胞数为21.38±12.81,与正常对照组和AdCMV组(53.64±11.27,44.23±12.75)比较,差异有统计学意义(P<0.05)。结论重组腺病毒载体介导TIMP2基因转染对体外生长主动脉平滑肌细胞增殖和侵袭有明显抑制作用。