【摘要】 背景:肠道菌群失调在溃疡性结肠炎(UC)发病机制中的作用备受关注,末端限制性片段长度多态性(TRFLP)分析已广泛用于UC肠黏膜菌群多样性的研究,但采集肠黏膜标本前清洁肠道对T-RFLP分析黏膜菌群多样性的影响尚未明确。目的:探讨肠道清洁对T-RFLP分析UC患者肠黏膜菌群多样性的影响。方法:纳入UC患者38例,根据结肠镜检查前是否行肠道清洁将患者分为洗肠组和未洗肠组,分别于结肠镜下取直肠、乙状结肠交界处黏膜组织,以T-RFLP分析肠黏膜细菌多样性。结果:聚类分析显示,洗肠组、未洗肠组菌落构成成分相似。洗肠组与未洗肠组的丰度、Simpson指数、均匀度指数相比差异无统计学意义(P>0.05),未洗肠组Shannon-Wiener指数较洗肠组显著增高(P<0.05)。MspⅠ酶切结果显示,281 bp为未洗肠组特有优势末端限制片段(T-RF),37 bp为洗肠组特有优势T-RF。两组共有优势T-RF的曲线下面积(AUC)比较显示,洗肠组490 bp T-RF较未洗肠组显著增高(P<0.05),其余优势T-RF的AUC差异无统计学意义(P>0.05)。结论:肠道清洁对T-RFLP分析UC肠黏膜菌群多样性总体无明显影响,但可能会造成部分罕见菌群减少。更多还原

【Abstract】 Background:Alteration of intestinal flora in the mechanism of ulcerative colitis(UC) has attracted more and more attention.Terminal restriction fragment length polymorphism(T-RFLP) analysis has been widely used in the research of mucosal bacteria diversity in UC,however,the effect of colonic cleansing before sample collection on T-RFLP analysis of mucosal bacteria diversity is unknown.Aims:To investigate the effect of colonic cleansing on T-RFLP analysis of mucosal bacteria diversity in UC.Methods:A total of 38 UC patients were enrolled and assigned into colonic cleansing group and non-cleansing group according to whether having colonic cleansing before endoscopy.Intestinal tissue samples were taken from rectum / sigmoid colon junction and the diversity of intestinal mucosal bacteria was detected by T-RFLP analysis.Results:Cluster analysis showed that the bacterial community in colonic cleansing group was similar with that in noncleansing group.No significant differences in richness,Simpson index and evenness index were found between colonic cleansing group and non-cleansing group(P > 0.05).Shannon-Wiener index in non-cleansing group was significantly higher than that in colonic cleansing group(P < 0.05).By MspⅠ restriction enzyme digestion,281 bp was the exclusive terminal restriction fragment(T-RF) in non-cleansing group,and 37 bp was the exclusive T-RF in colonic cleansing group.Comparing the area under the curve(AUC) of T-RF which shared by both groups,490 bp T-RF was significantly higher in colonic cleansing group than in non-cleansing group(P < 0.05),but no significant difference was found in contents of other T-RFs between the two groups(P > 0.05).Conclusions:Colonic cleansing has no significant effect on T-RFLP analysis of mucosal bacteria diversity in UC,yet it may reduce some rare species of bacteria in intestine.更多还原