Mucosa-associated bacteria in two middle-aged women diagnosed with collagenous colitis

AIM:To characterize the colon microbiota in two women histologically diagnosed with collagenous colitis using a culture-independent method.METHODS:Biopsies were taken from the ascending colon and the total DNA was extracted.Universal bacterial primers were used to amplify the bacterial 16S rRNA genes.The amplicons were then cloned into competent Escherichia coli cells.The clones were sequenced and identified by comparison to known sequences.RESULTS:The clones could be divided into 44 different phylotypes.The microbiota was dominated by Firmicutes and Bacteroidetes.Seven phylotypes werefound in both patients and constituted 47.5% of the total number of clones.Of these,the most dominating were clones similar to Bacteroides cellulosilyticus,Bacteroides caccae,Bacteroides thetaiotaomicron,Bacteroides uniformis and Bacteroides dorei within Bacteroidetes.Sequences similar to Faecalibacterium prausnitzii and Clostridium citroniae were also found in both patients.CONCLUSION:A predominance of potentially pathogenic Bacteroides spp.,and the presence of clones showing similarity to Clostridium clostridioforme were found but the overall colon microbiota showed similarities to a healthy one.Etiologies for collagenous colitis other than an adverse bacterial flora must also be considered.

脉冲电磁场和降钙素基因相关肽在肠粘膜萎缩中的作用

目的 探讨脉冲电磁场对结肠造瘘后旷置肠段粘膜的刺激作用 ,及降钙素基因相关肽在粘膜萎缩时的变化。方法 将 2 8只SD大鼠随机分为 3组 ,1组为对照组 (n =9) ,另外两组接受结肠造瘘、远端结肠旷置术 ,于术后 8d起连续 5d分别接受每日半小时的电磁场刺激 (n =10 )和不接受刺激 (n =9)。结果 病理组织学检查发现 ,电磁场刺激有效地防止了旷置部分结肠粘膜的萎缩。接受刺激的大鼠结肠粘膜的DNA和RNA含量均比未受刺激的高。结肠旷置后大鼠血浆中的降钙素基因相关肽有了明显的下降 ,而电磁场刺激未使之升高。结论 脉冲电磁场能在缺乏肠内营养的情况下刺激肠道粘膜的增生 ,但未改变降钙素基因相关肽的水平 ,提示了肠粘膜萎缩和阻断机理的复杂性。

Gut microbiota and surgical disease

Why should surgeons study gut microbiota and microbiome(totality of body's microorganisms and genomes)?There are at least three reasons.