后肾细胞微环境诱导胚胎干细胞向肾系细胞分化的实验研究

目的: 探讨胚胎后肾细胞微环境诱导胚胎干细胞(ESCs)分化为肾系细胞的作用。方法: 小鼠D3系胚胎干细胞通过悬滴法制备拟胚体(EBs),将EBs细胞与取自孕12.5 d小鼠胚胎的后肾细胞通过间接共培养以诱导其分化,即为共培养诱导组,设EBs细胞自然分化为对照组;采用免疫荧光染色法检测共培养第3、5、7 d后的EBs细胞Pax2、WT-1蛋白表达情况,通过逆转录PCR法检测诱导3 d后的EBs细胞Pax2、WT-1、Lim1、Sall1、Emx2、GDNF、Wnt4、BMP7、Nephl、Nephrin、KSP和CD24 mRNA的表达情况。结果: EBs细胞在诱导的第3 d即出现了全部肾发育相关基因的表达,其中共培养组Pax2、WT-1、Emx2、GDNF、Nephl、Nephrin、KSP和CD24的表达强于对照组;免疫荧光结果显示在诱导3 d后的EBs细胞中可观察到Pax2阳性细胞,阳性细胞数在共培养第5、7 d增多;诱导5 d后可观察到WT-1阳性细胞,对照组未见Pax2或WT-1蛋白阳性细胞出现。结论: 后肾细胞微环境可促进ESCs分化为肾系细胞。     

肾缺血对缺氧诱导microRNAs及VEGF-NOTCH信号分子的影响

目的 观察肾缺血性损伤后,缺氧诱导microRNAs及VEGF-NOTCH信号分子的表达变化,探讨肾缺血损伤后血管新生的可能调控途径.方法 选择雄性Balb/c小鼠20只,采用夹闭双侧肾蒂方法制备急性缺血肾损伤模型,假手术组设为对照组.通过观察缺血恢复后24 h小鼠肾功能及肾组织病理学改变确定模型成功.实时定量RT-PCR检测缺血恢复后4 h,24 h时缺氧诱导miRNA-210,miRNA-92a,VEGF,Flk-1及Notch1 mRNA表达水平;Western-blot检测缺血恢复后24 h,72 h时Flk-1蛋白的变化;免疫组织化学染色检测CD31表达,判断缺血组织微血管内皮细胞增生状况.结果 肾缺血恢复24 h小鼠肌酐、尿素氮明显升高(P＜0.05),光镜下观察大量小管上皮细胞肿胀、空泡变性坏死,肾小管管腔扩张,见上皮细胞碎片和管型,表明成功建立肾缺血损伤模型.肾缺血恢复4 h,24 h后,与正常组比较,肾组织miRNA-210上调倍数分别为(2.02±0.29),(5.58±0.16);miRNA-92a的表达上调倍数分别为(3.23±0.74),(1.53±0.33),P＜0.05;VEGF,Flk-1及Notch1 mRNA表达水平均升高(P＜0.05).缺血恢复后24 h,72 h时,Flk-1蛋白水平显著升高(P＜0.05),肾组织微血管密度明显增加.结论 肾缺血性损伤后可出现代偿性血管新生,且缺氧诱导miRNA如miRNA-92a,miRNA-210表达上调,与血管新生相关的信号分子VEGF及Notch1表达均升高,提示miRNA/VEGF-Notch1可能是肾缺血性损伤后血管新生的主要调控通路,从而为探讨缺血性损伤后血管新生的机制提供了依据.

Abstract：

Objective To investigate the expression changes of microRNAs and VEGF-NOTCH in renal ischemic injury in mice, and to explore the potential mechanism associated with renal angiogenesis.Method Male Balb/c mice were subjected to a standard renal ischemia to induce acute kidney injury (AKI) after 45 min of bilateral renal artery clamping. Following 4 h, 24 h of reperfusion or sham operation, kindey tissues were collected and subjected to detect the expression changes of microRNAs which relatived with angiogenesis and VEGF, Flk-1, Notch1 mRNA by Quantitative Real-time RT-PCR. Flk-1 protein was detected by Western blotting analysis at 24 h and 72 h following Ischemia/Reperfusion(I/R) injury. The expression of CD31 was examined in tissue sections by immunohistochemistry staining, and the microvessels in ischemic region of each group were counted. Results miRNA-210 and miRNA-92a expression increased significantly, with prominent changes at 4 h and 24 h after reperfusion( P ＜ 0.05 ). VEGF and Flk-1 mRNA expression and Flk-1 protein were increased in renal I/R compared with control group respectively (P＜0.05 ).Immunohistochemistry staining results of CD31 showed a significant increase of microvessels in renal ischemic region. Conclusion This study first reported the changes in miRNAs expression in response to kidney I/R in mouse. our results implied that miRNAs may be involved in targeting VEGF-Notch pathway signaling to regulate angiogenesis after renal I/R injury. It provided novel insights into the angiogenesis mechanism of renal ischemic injury.     

尿流动力学在女性压力性尿失禁TVT-O手术治疗中的临床价值

目的探讨尿流动力学在女性压力性尿失禁TVT-O手术治疗中的临床价值。方法采用TVT-O手术治疗26例女性压力性尿失禁患者。检测患者术前术后尿流动力学结果,并进行对比。根据患者主诉,排尿正常、完全自控、无尿失禁为治愈,尿失禁减少〉50%为改善。结果 26例患者手术后主观症状均明显改善。其中主观治愈24例,主观改善2例。尿流动力学检测指标中,最大尿流率在治疗前后无明显改变（P〉0.05）,最大尿道压和腹压漏尿点压力在治疗前后有明显改变（P〈0.05）,最大尿道闭合压（MUCP）在术前均为负值,术后均为正值。结论尿流动力学对于女性压力性尿失禁患者选择恰当的治疗方案,以及对TVT-O手术治疗效果的评估有着重要临床价值。     

尿道修复材料的研究及应用进展

尿道修复材料是尿道修复重建成败的关键,将尿道的修复材料分为自体组织材料、人工合成材料及组织工程化材料,从实验室和临床2方面对尿道修复材料的研究及应用进展进行综述.