反义AKT2 RNA抑制U251胶质瘤细胞生长的体内外研究

目的 研究反义AKT2RNA对U251人脑胶质瘤细胞在体内外的生长抑制效用。方法 将逆转录病毒pLXSN为载体的反义AKT2构建体转染U251人脑胶质瘤细胞系，应用蛋白印记确定基因转染前后AKT2的表达水平。流式细胞法与Matrigel基质生长实验评价肿瘤细胞转染前后的增殖活性。进一步应用裸鼠皮下荷瘤模型观察脂质体介导pLXSN、pLXSN-AS-AKT2基因治疗对U251细胞生长抑制作用。在28d的观察期内定期测量皮下肿瘤体积，对肿瘤标本应用免疫组化的方法进行AKT2和胶质纤维酸性蛋白（GFAP）表达比较。结果 脂质体介导pLXSN-AS-AKT2可显著抑制U251细胞AKT2表达。与对照组和pLXSN转染组比较，细胞周期分析结果表明AK—AKT2转染组进入S期的细胞数减少了8．5％～8．9％，而进入G0＋G1期细胞则增加了7．9％～8．6％。Matrigel基质生长实验显示对照组和pLXSN转染组细胞呈正常形态贴壁生长，而AS～AKT2转染组细胞不能贴壁生长，呈团块状簇集生长。裸鼠皮下荷瘤模型实验显示pLXSN-AS-AKT2显著抑制皮下肿瘤生长，组织病理学分析显示AS-AKT2转染组AKT2表达下降而GFAP表达上调。结论 体内外实验证明反义AKT2方法在抗胶质瘤增殖方面作用重要，AKT2可作为基因治疗胶质瘤的优选靶标。     

Cytochrome c mRNA levels decrease in senescent rat heart.

The concentration of mitochondria decrease in the heart as rodents age from maturity to senescence. The reason for this change is not known. One purpose of the present study was to determine if cytochrome c mRNA, representative of proteins of the inner mitochondrial membrane, decreased in the hearts of Fischer 344 rats as they aged from 12 to 24 months. Twenty-two percent less cytochrome c mRNA existed per given quantity of extracted RNA from the heart in 24-month-old rats as compared with the 12-month-old group. No change in the quantities of cardiac -actin mRNA, Ca²⁺/calmodulin protein kinase II mRNA or 18S rRNA was noted between 12- und 24-month-old hearts. Thus, the decrease in cytochrome c mRNA suggests that decreased in mRNAs for proteins of the inner mitochondrial membrane could play some role in the diminished concentration of mitochondria that exists in the senescent heart.     

Hemorrhagic fever with renal syndrome virus infection in livers studied by in situ hybridization and immunohistochemistry

ＨｅｍｏｒｒｈａｇｉｃｆｅｖｅｒｗｉｔｈｒｅｎａｌｓｙｎｄｒｏｍｅｖｉｒｕｓｉｎｆｅｃｔｉｏｎｉｎｌｉｖｅｒｓｓｔｕｄｉｅｄｂｙｉｎｓｉｔｕｈｙｂｒｉｄｉｚａｔｉｏｎａｎｄｉｍｍｕｎｏｈｉｓｔｏｃｈｅｍｉｓｔｒｙＹａｎｇＳｈｏｕｊｉｎｇ（杨守京）；Ｌ...     

2型糖尿病患者外周血白细胞iNOSmRNA表达的变化及意义

目的研究2型糖尿病DM患者外周血白细胞中iNOSmRNA表达的变化及其与糖尿病肾病DN发生、发展的关系。方法101例2型DM患者,根据尿微量白蛋白排泄率和血肌酐水平分为单纯DM组和不同的DN组,用原位杂交法检测外周血白细胞iNOSmRNA表达的阳性细胞的百分率,并与21例健康体检者进行比较。结果早期DN组白细胞iNOSmRNA表达的百分率明显高于对照组、DM组及晚期DN组(P<0.001)。结论外周血白细胞iNOSmRNA表达的变化参与了DN的发生、发展。     

Protective effect of interferon-α on the DNA- and RNA-degrading pathway in anti-Fas-antibody induced apoptosis

Aim: Fas membrane-associated polypeptide antigen is a receptor molecule responsible for apoptosis-mediated signals. In animal models of acute viral hepatitis, apoptosis of hepatocytes is mediated by Fas-death receptors; therefore, the aim of this study was to evaluate the effect of interferon (IFN)-alpha on apoptotic markers and nuclease activity against different coding and non-coding single and double stranded RNAs during Fas-induced liver apoptosis. Methods: An in vivo experiment was performed with simultaneous administration of anti-Fas (CD95) antibodies and IFN-alpha, and an in vitro experiment was performed in hepatocyte cultures treated with anti-Fas antibodies and IFN-alpha. Results: Detection of apoptosis using Annexin V-FITC/propidium iodide, Bcl-2 and Bax expression in hepatocyte cultures confirmed the appearance of early apoptotic events and progression toward late apoptosis after anti-Fas antibody treatment. IFN-alpha had a tendency to retard the apoptosis process in Fas-induced apoptosis by increasing the number of viable cells and decreasing the number of cells in late apoptosis, by increasing the percentage of Bcl-2 positive cells, by decreasing the percentage of Bax positive cells, and by decreasing the nuclease activity compared to the anti-Fas antibody treated group. Total DNA and RNA concentration was much reduced in the Fas group and DNA fragmentation assay provided evidence for increased DNA degradation. Enhanced nuclease activity against DNA, rRNA, poly(A), poly(C), poly(U), poly(I:C), and poly(A:U) was manifested in the anti-Fas antibody treated group, except for the inhibitory-bound alkaline RNase. Conclusions: The results demonstrate that the RNA-degrading pathway in Fas-induced apoptosis can accelerate the liberation of the latent enzyme from the inhibitor complex. IFN-alpha prevented enormous, Fas-ligand induced degradation of all the substrates used in this experimental study, most probably due to similarities in the signal transduction pathways. Investigations of death receptor-induced apoptosis may lead to novel treatment combinations for patients with acute or chronic liver diseases.     

乙型肝炎病毒转基因小鼠体内肝靶向反义RNA抗病毒疗效研究

目的：探讨半乳糖修饰的反义RNA真核表达质粒在乙型肝炎病毒转基因小鼠体内的抗病毒作用。方法：以半乳糖多聚赖氨酸（Gal-PLL)作肝靶向载体，将乙型肝炎病毒基因C区的反义RNA真核表达重组质粒（pCEP4-aC）制备为Gal-PLL－pCEP4-aC。将24只血清HBV DNA、HBsAg阳性的小鼠，随机等分为Gal-PLL－pCEP4-aC治疗组、Gal-PLL-pCEP4对照组和生理盐水阴性对照组，于实验第1天尾静脉分别注射Gal-PLL－pCEP4-aC、Gal-PLL－pCEP4（100μg/只）和等体积的生理盐水，观察治疗前后血清HBV DNA以及HBsAg变化。结果：Gal-PLL－pCEP4-aC治疗组21天时血清HBV－DNA转阴率62．5％（5／8），且7，14，21天时血清HBsAg明显降低；而Gal-PLL－pCEP4组血清HBV DNA转阴1只（1／8），生理盐水组8只均未转阴，两组用药后血清中HBsAg与用药前比较差异性均不明显（P＞0．05）。结论：肝靶向反义RNA能在乙肝基因小鼠体内抑制HBV的复制和抗原表达。     

Prevalence of anti-HCV in institutionalised mentally handicapped subjects

Data on the prevalence of antibody to hepatitis C virus among 278 subjects in an institution for the mentally handicapped were analysed by risk factors. A prevalence of 4% was found, higher than blood donors belonging to the same area (1.4%). No differences in prevalence with regard the length of residence, age, sex, degree of retardation or for presence of HBV markers were observed.     

应用NASBA定量检测HCV RNA的研究进展

NASBA（nucleic acid sequence-based amplification)即核酸序列依赖性扩增法，是由一对引物介导的、连续均一的、体外特异性核苷酸序列等温扩增的RNA新技术。反应在42℃进行，可在2h内将RNA模板扩增约10^9倍。本文综述NASBA在HCV RNA定量检测中的应用。