N-甲基-N-亚硝基脲诱导大鼠视网膜变性早期基因表达谱分析

背景N-甲基-N-亚硝基脲（MNU）诱导的大鼠光感受器细胞凋亡可用于研究视网膜变性类疾病,但视网膜变性类疾病早期基因水平的研究尚未见报道。目的应用基因芯片技术研究MNU诱导的视网膜变性大鼠早期基因表达谱的变化。方法6周龄雌性SD大鼠50只分为正常组20只、12h模型组20只和24h模型组10只。模型组大鼠皮下注射MNU（40mg／kg）,正常组大鼠皮下注射等容量的生理盐水作为对照。分别于造模后12、12、24h处死正常组和12h模型组、24h模型组大鼠,大鼠右眼球进行常规视网膜组织病理学检查,正常组和12h模型组大鼠左眼的新鲜视网膜用基因芯片技术检测差异基因的表达,用荧光实时定量PCR（real—timePCR）法验证基因芯片技术检测出的差异表达率≥2．0的基因mRNA表达水平。结果全层视网膜厚度测量表明,24h模型组大鼠的厚度值明显低于正常组大鼠和12h模型组大鼠,差异均有统计学意义（t=9．926,P=0．002;t=2．736,P=0．028）。24h模型组大鼠外核层厚度值为（26．58±2．90）仙m,明显低于正常组的（38．11±1．01）μm和12h模型组的（35．07±3．03）μm,差异均有统计学意义（t=6．028,P=0．009;f=6．839,P=0．006）,正常组与12h模型组间大鼠全层视网膜厚度和外核层厚度值比较差异均无统计学意义（全层厚度：t=1．541,P=0．324;外核层厚度：t=2．040,P=0．134）。大鼠cDNA基因芯片技术检测结果表明,12h模型组大鼠全部17000个基因的表达谱中涉及生物过程的基因为142个,涉及分子功能的基因为94个,排除重复基因共有74个基因,差异表达基因主要涉及丝裂原活化蛋白激酶（MAPK）通路、Toll样受体通路和细胞凋亡通路。对基因芯片技术检测的差异表达率≥2．0的基因进行的real．timePCR定量分析表明,CCL2、,L—Jb、CCL3、c-fos、c—myc、p53和MMP3基因mRNA表达值与基因芯片技术检测的表达趋势一致。结论MNU诱导的视网膜变性早期有明显的基因表达改变。基因芯片检测的基因表达改变结果与real—timePCR定量分析结果一致。     

基因芯片分型与实时荧光PCR筛查成都地区妇女宫颈HPV-DNA感染结果比较

目的了解成都地区HPV亚型的感染情况;评价基因分型（genotyping）与实时荧光定量PCR（real-time PCR）两种人乳头瘤病毒（HPV）检测方法的差异性,为临床应用提供参考。方法对2012年1月-2013年6月间来院就诊的女性,其中3537名进行基因芯片检测,991名进行实时荧光PCR检测。所得数据用SPSS 17.0进行统计分析。结果基因芯片分型法检测出阳性1315例,阳性率37.18%;实时荧光PCR检测出阳性137例,阳性率13.82%,两种方法检出率差异明显。基因分型法显示,HPV6、11、16、58、43型位居前五;荧光定量PCR显示HPV6、11、16、52、58在前五位。结论成都地区低危感染以HPV 6、11型为主,高危以16型为主,次之52、58型;基因芯片分型与临床HPV-DNA筛查检出率高,优于荧光定量PCR法。     

H pylori iceA alleles are disease-specific virulence factors

AIM: To characterize and compare genotype profiles of H pylori strains isolated from patients with chronic gastritis and duodenal ulcer in western part of Turkey. METHODS: A total of 46 patients [30 chronic gastritis (CG) and 16 duodenal ulcer (DU)] who had undergone endoscopy because of dyspeptic complaints were studied. The antral biopsy specimens were evaluated for the presence of H pylori by rapid urease test and culture, and the genotype profiles were determined by real-time PCR. RESULTS: The cagA gene was observed in 43 (93.5%) isolates. The vacA s1m2 genotype was the predominant subtype, found in 63.3% and 68.7% of isolates in patients with CG and DU, respectively. Twenty (66.6%) isolates from patients with CG were iceA2 positive while the iceA1 was predominant in those with DU (68.8%). In terms of the association of the iceA alleles to other genes, both alleles were significantly associated with the cagA vacA s1m2 genotype. CONCLUSION: The prevalent circulating genotypes in CG and DU were cagA vacA s1m2 iceA2 and cagA vacA s1m2 iceA1 genotype, respectively. It was found that cagA vacA s1m2 genotype seems to be common virulence factors in both CG and DU while iceA alleles show specificity for gastroduodenal pathologies in this study.