Acute cytomegalovirus infection modulates the intestinal microbiota and targets intestinal epithelial cells

Primary and recurrent cytomegalovirus (CMV) infections frequently cause CMV colitis in immunocompromised as well as inflammatory bowel disease (IBD) patients. Additionally, colitis occasionally occurs upon primary CMV infection in patients who are apparently immunocompetent. In both cases, the underlying pathophysiologic mechanisms are largely elusive - in part due to the lack of adequate access to specimens. We employed the mouse cytomegalovirus (MCMV) model to assess the association between CMV and colitis. During acute primary MCMV infection of immunocompetent mice, the gut microbial composition was affected as manifested by an altered ratio of the Firmicutes to Bacteroidetes phyla. Interestingly, these microbial changes coincided with high-titer MCMV replication in the colon, crypt hyperplasia, increased colonic pro-inflammatory cytokine levels, and a transient increase in the expression of the antimicrobial protein Regenerating islet-derived protein 3 gamma (Reg3γ). Further analyses revealed that murine and human intestinal epithelial cell lines, as well as primary intestinal crypt cells and organoids represent direct targets of CMV infection causing increased cell death. Accordingly, in vivo MCMV infection disrupted the intestinal epithelial barrier and increased apoptosis of intestinal epithelial cells. In summary, our data show that CMV transiently induces colitis in immunocompetent hosts by altering the intestinal homeostasis.     

Management of midgut volvulus with extensive necrosis by “patch,drain, and wait” in early infancy and childhood

Midgut volvulus with extensive intestinal necrosis in the newborn period and in early infancy and childhood presents a difficult therapeutic dilemma of how to control sepsis and preserve a maximum and life-sustaining amount of large and small intestine. This problem is similar to that faced in cases of necrotizing enterocolitis with extensive intestinal ischemia and necrosis. The successful use of the patch, drain, and wait approach in necrotizing enterocolitis suggested its potential usefulness in midgut volvulus with similarly extensive necrosis in early life [7]. The basic principles of this approach involve maximum bowel salvage by avoidance of both resection and enterostomy; extensive bilateral Penrose drainage of the peritoneal cavity to provide an exit for sepsis and debris for peritonitis control; and de facto enterostomies for potential enteric fistula capture, gastrostomy for upper gastrointestinal tract venting and decompression, and Broviac catheter placement for long-term hyperalimentation. Three cases involving the successful use of this approach are reported.     

消化道肿瘤患者手术前后肠道通透性检测的临床意义

目的了解消化道肿瘤患者手术治疗前后肠道通透性的改变,探讨肠黏膜屏障功能是否受腹部手术的影响。方法选择手术治疗消化道肿瘤患者16例,在术前、术后1周口服乳果糖、甘露醇液后采集6小时尿样,尿样和乳果糖、甘露醇的标准样经肟化处理后通过气相色谱分析仪糖分子探针法进行检测分析其含量及比值。结果甘露醇峰、乳果糖峰出峰时间稳定,峰面积随含量增加而增加,并且呈线性相关;消化道肿瘤手术前后尿样中的乳果糖含量和乳果糖/甘露醇有显著性差异,乳果糖含量增高,而甘露醇含量手术前后无显著性差异。结论消化道肿瘤手术会导致肠黏膜通透性增加,出现肠黏膜屏障功能损害。     

胃癌术后早期肠内营养的意义

目的探讨胃癌术后早期肠内营养(EN)的安全性和有效性。方法采用随机对照的方法,将68例胃癌术后患者随机分为EN组和肠外营养组(PN组),分别经鼻肠管、经颈内静脉进行营养支持,观察两组患者消化道并发症的发生情况、继发感染情况以及术后白蛋白、前白蛋白、淋巴细胞计数等。结果EN组术后腹胀、腹泻的发生率较PN组,但患者均能耐受。EN组1例患者因吻合口水肿、输入襻不完全性梗阻而发生恶心、呕吐,余患者无恶心、呕吐；PN组发生肺部感染和导管感染各1例。EN组肛门排气、排便时间早于PN组(P=0．01)。与PN组比较,EN组术后白蛋白略有下降,前白蛋白升高。结论早期EN可降低术后感染的发生率,有利于胃癌患者术后的恢复。     

基于16S rDNA测序的肠道菌群探讨解郁祛痰化浊方对高脂饮食大鼠肠-肝轴的影响

目的 研究解郁祛痰化浊方（JQHP）对高脂饮食大鼠肠道菌群的影响，探讨中药调控肠道微生物群进而恢复肠-肝轴的平衡。方法 将70只雄性SPF级别Wistar大鼠随机分为正常组（10只）与模型组（60只），正常组饲喂正常饲料，模型组饲喂高脂饲料。12周后将模型组随机分为6组，每组10只，即模型组，血脂康组，立普妥组，JQHP低、中、高剂量组。JQHP低、中、高剂量组分别灌胃JQHP颗粒剂0.4，0.8，1.6 g·kg^-1，立普妥组予立普妥2 mg·kg^-1，血脂康组予血脂康0.1 g·kg^-1，正常组和模型组大鼠灌胃同等量蒸馏水，连续灌胃8周后收集粪便，进行16S rRNA基因测序，行腹主动脉取血检测血脂，取肝脏组织及回肠组织苏木素-伊红（HE）染色后进行病理形态学观察。结果 与正常组比较，模型组大鼠血脂四项总胆固醇（TC），甘油三酯（TG），低密度脂蛋白胆固醇（LDL-C）均见明显升高，高密度脂蛋白胆固醇（HDL-C）降低（P<0.01）；与模型组比较，血脂康组、立普妥组TC，TG显著性下降（P<0.01），血脂康组HDL-C升高（P<0.05）。JQHP中剂量组较模型组对肝脏脂肪样变有一定的缓解作用，可以减轻炎性细胞的浸润情况。JQHP可使回肠结构淋巴组织增生情况好转，且中剂量组疗效最显著。Shannon曲线结果表明，与正常组比较，JQHP中剂量组显著提高（P<0.01）；与模型组比较，JQHP中、高剂量组明显升高（P<0.05，P<0.01）；与JQHP中剂量组比较，其他用药组降低（P<0.05，P<0.01）。主成分多样性分析（PCA）示中药中剂量组多样性和丰度高于其他用药组。线性判别分析（LDA）中，与正常组比较，模型组拟杆菌纲，瘤胃球菌科，拟杆菌S24-7，瘤胃球菌UCG-005下调（P<0.01），脱硫弧菌目、丹毒丝菌目、毛螺菌科上调（P<0.05，P<0.01）。与模型组比较，JQHP中剂量组的拟杆菌纲，瘤胃球菌科，拟杆菌S24-7，瘤胃球菌UCG-005上调（P<0.05，P<0.01），丹毒丝菌目下调（P<0.01）。与JQHP中剂量组比较，其他用药组拟杆菌纲，瘤胃球菌科，拟杆菌S24-7，瘤胃球菌UCG-005中降低（P<0.05，P<0.01），在丹毒丝菌目、毛螺菌科中升高（P<0.05，P<0.01）。结论 JQHP调整肠道物种丰度和多样性，改善肝脏组织和回肠黏膜状态，调节血脂水平，恢复正常肠道生态环境，可能与调节与炎症相关的肠道菌群而恢复肠-肝轴平衡有关，以中剂量组效果最佳。     

The effects of the microbiota on the host immune system

Abstract

The human gastrointestinal track harbors hundreds of species of commensal organisms, collectively known as microbiota. The composition of the intestinal microbiota is changeable by various factors, such as host genotype, diet, antibiotics, pathogen infections, among others. Changes in these factors can cause microbiome disruption known as dysbiosis, leading to the outgrowth of potential pathogenic bacteria or decrease in the number of beneficial bacteria. Dysbiosis has been implicated in numerous inflammatory and autoimmune diseases. This review is focused on host–microbiota interactions, specifically on influence of bacterial-derived signals on immune cell function and the mechanisms by which these signals modulate the development and progression of inflammatory and autoimmune diseases.     

Skin sensitivity and skin microbiota: Is there a link?

Sensitive skin is defined by the occurrence of unpleasant sensations, accompanied or not by erythema, in response to stimuli which normally should not provoke such sensations and that cannot be linked to skin disease. Even if its pathophysiology is not completely known, hyper‐reactivity of the cutaneous nervous system associated with an abnormal skin barrier has been hypothesized as a primary culprit including more recently a role of the cutaneous microbiota. The objective of this short review is to discuss the relationship between the skin microbiota, skin sensitivity and the skin barrier function.     

肠道菌群与围手术期神经认知障碍研究进展

围手术期神经认知障碍(perioperative neurocognitive disorders,PND)是麻醉和手术相关的常见并发症,其机制和干预研究一直以来都是麻醉和围手术期医学领域的热点和重点问题。目前,大量证据证实肠道菌群与大脑之间存在着重要的交互关联,称为肠-脑轴。肠道菌群是肠-脑轴重要一环,其稳态对神经认知功能起着重要的调控作用。文章基于目前的研究,就麻醉和外科手术对肠道菌群的影响,肠道菌群失调在PND中的作用及其潜在机制,以及通过调节肠道菌群对PND的干预作用等方面进行综述,以期为临床及科学研究提供参考。     

Antimicrobial peptides play a functional role in bumblebee anti-trypanosome defense

Bumblebees, amongst the most important of pollinators, are under enormous population pressures. One of these is disease. The bumblebee and its gut trypanosome Crithidia bombi are one of the fundamental models of ecological immunology. Although there is previous evidence of increased immune gene expression upon Crithidia infection, recent work has focussed on the bumblebee’s gut microbiota. Here, by knocking down gene expression using RNAi, we show for the first time that antimicrobial peptides (AMPs) have a functional role in anti-Crithidia defense.