Differences in faecal bacterial communities in coeliac and healthy children as detected by PCR and denaturing gradient gel electrophoresis

Coeliac disease (CD) is a chronic inflammatory disorder of the small intestinal mucosa. Scientific evidence supports a role of the gut microbiota in chronic inflammatory disorders; yet information is not specifically available for CD. In this study, a comparative denaturing gradient gel electrophoresis analysis of faecal samples from coeliac children and age-matched controls was carried out. The diversity of the faecal microbiota was significantly higher in coeliac children than in healthy controls. The presence of the species Lactobacillus curvatus, Leuconostoc mesenteroides and Leuconostoc carnosum was characteristic of coeliac patients, while that of the Lactobacillus casei group was characteristic of healthy controls. The Bifidobacterium population showed a significantly higher species diversity in healthy children than in coeliacs. In healthy children, this population was characterized by the presence of Bifidobacterium adolescentis. Overall, the results highlighted the need for further characterization of the microbiota in coeliac patients, and suggested a potential role of probiotics and/or prebiotics in restoring their gut microbial balance.     

Composition and temporal stability of gastrointestinal microbiota in irritable bowel syndrome--a longitudinal study in IBS and control subjects

Irritable bowel syndrome (IBS) is a common intestinal disorder that includes continuous or recurrent intestinal pain and discomfort and altered bowel habits. The pathophysiology of IBS is incompletely understood, but it may involve an altered intestinal microbiota. The aim of the present study was to compare the composition and temporal stability of faecal microbiota of IBS patients and healthy controls by applying culture-based techniques and PCR-DGGE analysis. No difference in the prevalence or mean culturable manners of bacteroides, bifidobacteria, spore-forming bacteria, lactobacilli, enterococci or yeasts were observed between the IBS and the control groups, whereas slightly higher numbers of coliforms as well as an increased aerobe:anaerobe ratio was observed in the IBS group. PCR-DGGE revealed more temporal instability in the predominant bacterial population of IBS subjects than in controls. In 9 out of 21 IBS subjects and 5 out of 17 controls the PCR-DGGE profiles obtained from the samples of the same individual on different occasions (sampling points 0, 3 and 6 months) were clearly different. However, the instability in some of the IBS subjects could partly be explained by the antibiotic consumption during the study. The present study suggests that instability of intestinal microbiota may be involved in IBS. However, further studies are needed to associate the instability with specific IBS symptoms or with specific bacterial groups and species.     

两种乳酸菌胞外多糖对人体粪便菌群的影响

目的 在体外利用7名志愿者的新鲜粪便作为来源,选择菊粉作为对照,研究干酪乳杆菌LC2W与鼠李糖乳杆菌Y37胞外多糖对人体肠道菌群的影响.方法 利用PCR-DGGE(变性梯度凝胶电泳)方法分析样品中菌群组成,高效液相色谱分析培养前后胞外多糖组分变化.结果 与菊粉相比,粪便菌群在添加乳杆菌胞外多糖培养后,Parabacteroides类群细菌明显增加,4名志愿者粪便样品中出现明显的双歧杆菌条带,两种乳杆菌胞外多糖对粪便菌群的影响差异无统计学意义;而添加菊粉培养后,Bacteroides类群细菌的条带明显增加.两种乳杆菌胞外多糖中主要是大分子量的部分被利用.结论 干酪乳杆菌LC2W与鼠李糖乳杆菌Y37的胞外多糖在体外有调节粪便菌群的作用.     

抗性淀粉对HFA小鼠肠道菌群的影响

目的 以人源菌群(HFA)小鼠为研究模型,观察抗性淀粉(RS)对高脂饮食诱导的肥胖小鼠肠道菌群的多样性的影响.方法 将30只无菌小鼠接种健康人志愿者的粪便悬液构建HFA小鼠模型后,随机分成3组,一组喂养含20％的抗性淀粉的高脂饲料(RS组),一组喂养纯高脂饲料(CK组),一组喂养普通饲料(CONV组),取第0周和第8周的小鼠新鲜粪便,用PCR-DGGE分析3组小鼠的肠道菌群的相似性和多样性.结果 3组小鼠在第0周时肠道菌群多样性的相似度达到79％～87％,与人的肠道菌群相似性达到39％,说明构建HFA小鼠模型成功,第8周时,3组之间的均匀度(E)和Shannon指数差异无统计学意义(P＞0.05),而丰富度(S)在高脂组(CK)与普通饲料组(CONV)和抗性淀粉组(RS)之间差异都有统计学意义(P＜0.05),说明高脂饮食引起肠道菌群多样性增加,而抗性淀粉则能降低这种多样性.结论 抗性淀粉可以显著影响HFA小鼠的肠道菌群多样性.     

西芹提取液对高脂小鼠肠道菌群平衡的影响

目的应用PCR-DGGE技术评价西芹对昆明小鼠肠道菌群平衡的影响。方法给予小鼠高脂饲料,复制高脂模型,模型复制成功后,每日给予小鼠西芹提取液灌胃,连续28 d。分别在实验的0、14和42 d,收集每只小鼠粪便,提取基因组DNA,应用PCR-DGGE(聚合酶链式反应——变性梯度凝胶电泳)技术获得肠道菌群分子指纹图谱,针对相似性、多样性分析及优势条带的序列进行分析。结果高脂饲料喂养后肠道益生菌约氏乳杆菌等趋近消失,出现了特异菌真杆菌,而西芹灌胃组和食用基础饲料组真杆菌数量显著减少,且西芹灌胃组作用大于食用基础饲料自然恢复组。结论西芹对高脂小鼠肠道菌群的平衡有显著的恢复作用。     

茶多酚对ApoE~(-/-)小鼠肠道菌群多样性的影响

目的以高脂饲料饲养的SPF级C57 BL/6 ApoE-/-小鼠作为动物模型,研究茶多酚采食对其肠道菌群多样性的影响。方法通过随机饮水的方式给予ApoE-/-小鼠0.4、0.8和1.6 g/L的茶多酚,处理14 d时用PCR-DGGE分析对照组(CK)和茶多酚组小鼠新鲜粪便中肠道菌群的相似性和多样性。结果 UPGMA聚类分析表明,低剂量茶多酚组(LTP)、中剂量茶多酚组(MTP)这两组与对照组(CK)、高剂量茶多酚组(HTP)聚为两大簇。PCA分析显示,LTP组与CK组、MTP组、HTP组分别聚集在不同位置,有明显界限;多样性数据分析显示:CK组DGGE图谱的丰富度和Shannon-Wiener指数(H')与茶多酚组差异无统计学意义(P0.05);CK组与MTP组的均匀度(E)差异存在统计学意义(P0.05,P=0.015),说明中剂量茶多酚作用14 d后与对照组肠道菌群的菌群分配相比均一性显著下降。结论连续处理14 d时CK组与LTP组、MTP组小鼠肠道菌群差异有统计学意义,即茶多酚对ApoE-/-小鼠肠道菌群多样性有显著影响。     

粪菌移植治疗肠易激综合征研究进展

粪菌移植(faecal microbiota transplantation,FMT)是将从健康供体获得的粪便悬液转移至患者消化道,从而恢复肠道正常微生物组成和功能的一种治疗方法。近年来,FMT治疗肠易激综合征(irritable bowel syndrome,IBS)的疗效和经济效益越来越受到研究者的重视。这种方法已经成为艰难梭菌感染(Clostridium difficile infection,CDI)的成熟替代疗法。此外,FMT还在炎症性肠病(inflammatory bowel disease,IBD)和胃肠疾病以外的疾病,如心血管疾病、自身免疫性疾病和代谢综合征等多种疾病的治疗中取得了显著进展。关于FMT仍有许多未解的问题,需要在这一领域进行更多研究。本文就IBS的发病机制、FMT的疗效和安全性进行综述。     

细菌性阴道病及其合并盆腔炎患者的阴道菌群分析

目的 对比细菌性阴道病及其合并盆腔炎患者与健康个体的阴道菌群,分析阴道菌群的结构,为确定该疾病的特征细菌及研究致病机制奠定基础。方法 采用临床Amsel标准筛选的17例细菌性阴道病患者、13例细菌性阴道病合并盆腔炎患者和52例健康者,使用无菌拭子采集阴道后穹窿分泌物以提取细菌基因组DNA。采用PCR技术扩增上一步得到的16S rRNA片段,而后将扩增产物通过变形梯度凝胶电泳（DGGE）分离以得到阴道细菌种属结构图谱,应用Quantity One软件进行聚类分析,应用凝胶测序法进行特异条带分析。检测16S rRNA基因,具体研究样品中的物种分类。结果 细菌性阴道病及其合并盆腔炎患者的阴道菌群的构成与健康者相比较具有显著性差异。其中,Firmicutes等菌门细菌减少,Actinobacteria等菌门细菌增多;G. vaginallis、P. vaginallis等厌氧菌数量均增加,L.crispatus、L.iners等益生菌数量均有减少。结论 细菌性阴道病及其合并盆腔炎患者的生殖道内的合并感染改变了阴道内的原有微生态平衡。两组疾病组患者的阴道菌群构成相比于健康对照组变化明显。     

孕妇肠道微生物组成与孕妇及新生儿糖脂代谢相关性研究

目的研究孕妇肠道微生物组成与孕妇以及新生儿糖脂代谢的相关性。方法选择2017年6月至2018年9月在大连市妇幼保健院定期产检的诊断为妊娠期糖尿病(GDM)的孕妇89例为GDM组,血糖正常孕妇96例为对照组。收集孕妇一般资料,孕妇和新生儿糖脂代谢物、孕妇粪便进行微生物检测。结果 GDM组孕妇空腹血糖、甘油三酯明显高于对照组,高密度脂蛋白水平明显低于对照组(均P<0.05)。GDM新生儿脂联素和血糖明显低于对照组,胰岛素和糖化血红蛋白明显高于对照组(均P<0.05)。对照组孕妇肠道微生物中拟杆菌(Bacteroides)丰富度最高(36.6%),其次是普雷沃菌(Prevotella)(15.3%)、柔嫩梭菌(Faecalibacterium)(10.2%)、考拉杆菌(Phascolarctobacterium)(7.2%)。GDM组孕妇肠道微生物中拟杆菌(Bacteroides)丰富度最高(29.4%),其次是柔嫩梭菌(Faecalibacterium)(19.7%)、普雷沃菌(Prevotella)(11.1%)、考拉杆菌(Phascolarctobacterium)(9.3%)。柔嫩梭菌(Faecalibacterium)与孕妇空腹血糖呈正相关(r=0.377 6,P=0.027 6),拟杆菌(Bacteroides)、埃希菌(Escherichia)与孕妇甘油三酯呈负相关(r=-0.027 5,-0.585 8,P=0.023 7,0.041 3)。柔嫩梭菌(Faecalibacterium)与新生儿空腹血糖呈负相关(r=-0.397 6,P=0.027 6)。结论 GDM孕妇肠道微生物构成与血糖正常孕妇不同,菌群丰富度和多样性较低,并且孕妇肠道菌群与其及新生儿的糖脂代谢相关,调节孕妇肠道菌群或有利于改善其与新生儿的糖脂代谢功能。     

急性心肌梗死患者肠道菌群多样性分析

目的 初步探究急性心肌梗死患者肠道菌群的多样性。方法 选择2015年6月至2016年3月于大连大学附属中山医院住院治疗的急性心肌梗死患者作为观察组,年龄51~70岁。选择同期经冠脉造影排除冠心病的住院患者为对照组,年龄51~70岁。排除近1个月内发生感染、炎性肠病及应用抗生素的患者。所有患者按性别与年龄分为A、B、C、D组。直接从患者粪便标本中提取细菌总DNA,PCR扩增后进行梯度凝胶电泳（DGGE）分析。结果 DGGE分析显示急性心梗患者肠道菌群丰度均较对照组下降。A组中观察组与对照组患者电泳条带数为(33.71±4.39) vs (38.71±2.56),t=－2.058,P=0.040;C组患者为(31.14±2.67) vs (35.29±3.55),t=－2.005,P=0.045;差异均具有统计学意义。B与D组中心梗患者肠道菌群丰度亦有下降趋势,但与对照组比差异无统计学意义。UPGAM法聚类分析显示除D组外,各组中观察组与对照组患者肠道菌群呈现分离现象;急性心梗患者肠道菌群有较高相似性,与非冠心病患者肠道菌群差异明显。结论 急性心梗与非冠心病患者肠道菌群存在差异,急性心梗患者肠道菌群多样性较低。肠道菌群改变可能与急性心肌梗死存在一定相关性。     

Changes in fecal microbiota of healthy dogs administered amoxicillin

The effect of oral amoxicillin treatment on fecal microbiota of seven healthy adult dogs was determined with a focus on the prevalence of bacterial antibiotic resistance and changes in predominant bacterial populations. After 4–7 days of exposure to amoxicillin, fecal Escherichia coli expressed resistance to multiple antibiotics when compared with the pre-exposure situation. Two weeks postexposure, the susceptibility pattern had returned to pre-exposure levels in most dogs. A shift in bacterial populations was confirmed by molecular fingerprinting of fecal bacterial populations using denaturing gradient gel electrophoresis (PCR-DGGE) of the 16S V3 rRNA gene region. Much of the variation in DGGE profiles could be attributed to dog-specific factors. However, permutation tests indicated that amoxicillin exposure significantly affected the DGGE profiles after controlling for the dog effect ( P =0.02), and pre-exposure samples were clearly separated from postexposure samples. Sequence analysis of DGGE bands and real-time PCR quantification indicated that amoxicillin exposure caused a shift in the intestinal ecological balance toward a Gram-negative microbiota including resistant species in the family Enterobacteriaceae .     

肠道菌群失衡与乳糜泻:重要性及可能机制

乳糜泻(Celiac disease,CeD)是基因易感人群摄入麸质后所发生的一种自身免疫性肠道疾病.越来越多证据表明,"第二人类基因组"——肠道菌群参与了CeD的发生与发展.相对于健康人群,CeD患者的肠道菌群多样性虽然增高,但有益菌减少,促炎细菌增多,并伴随菌群功能及代谢状态的改变.然而,这种菌群失衡是如何发生的,...     

Comparison of fecal microbiota and polyamine concentration in adult patients with intractable atopic dermatitis and healthy adults

Fecal microbiota and polyamine concentration obtained from eleven intractable adult-type atopic dermatitis (AD) patients and thirteen healthy adults were compared. Fecal microbiota were analyzed using terminal-restriction fragment length polymorphism. The fecal microbiota of volunteers were divided into two clusters, A (n=16) and B (n=8), and the number of AD patients was found to be higher in Cluster B than Cluster A, suggesting that there are relationships between the obstinacy of intractable adult-type AD and intestinal microbiota in Cluster B. Fecal spermidine concentration in Cluster B were lower than that in Cluster A significantly (P<0.05). Fecal putrescine concentration in Cluster B also tended to be lower than that in Cluster A. Terminal-restriction fragment (T-RF) of 122 bp generated by digestion with Hha I, which were predicted as unknown bacteria, were detected characteristically in Cluster A. In contrast, T-RFs of 368/9 bp generated by digestion with Hha I, which were predicted as Enterobacteriaceae, were detected characteristically in Cluster B. These bacteria are closely associated with intestinal polyamine concentration. These findings raise the possibility that a low concentration of intestinal polyamines produced by intestinal microbiota is one of the important factors in the onset of intractable adult-type AD.     

质子泵抑制剂对慢性肝病患者肠道微生态的影响

目的探究质子泵抑制剂(PPIs)对慢性肝病患者肠道微生态的影响。方法选取郑州市第六人民医院2018年12月至2019年3月诊断及拟行PPIs治疗的慢性肝病患者31名,使用奥美拉唑进行治疗,20 mg/次,2次/d,疗程4周,检测治疗前后肠道菌群的构成。结果治疗前后患者肠道菌群构成差异显著:治疗后患者肠道菌群在Shannon指数(4.61±0.62 vs 5.01±0.83;t=2.889,P=0.005)、Simpson指数(0.89±0.09 vs 0.95±0.11;t=3.159,P=0.002)显著低于治疗前;治疗前患者肠道菌群中Coriobacteriaceae、Eggerthella、Ruminococcus、Anaerotruncus、Dorea、Turicibacter、Paraprevotella的相对丰度显著高于治疗后,治疗后肠道菌群中Veillonellaceae、Campylobacter、Haemophilus、Streptococcus、Streptococcaceae、Lactobacillus、Lactobacillaceae的相对丰度显著高于治疗前(均P<0.05)。结论PPIs可改变慢性肝病患者肠道菌群的构成。     

山西省健康人群的肠道菌群组成特征

目的探索山西省健康人群的肠道菌群组成特征及性别和年龄对肠道菌群组成的影响。方法应用16S rRNA基因测序技术,对山西省99名健康个体的粪便细菌DNA进行测序分析。结果山西省健康人群的肠道菌群在属水平分为两个集群,相对丰度最高的分别是拟杆菌属和普氏菌属;在区分这两个集群中,拟杆菌属与普氏菌属的曲线下面积（AUC）分别是0.97、1.00。男性组与女性组的物种丰富度（richness）和多样性（diversity）差异都无统计学意义（均P>0.05）,基于Bray-Curtis距离的主坐标分析（PCoA）图显示两组人群的样本分布没有明显分离（相似性分析：r=-0.0296,P>0.05）,LEfSe分析显示与性别分组有关的细菌很少。30-39岁、40-49岁和50-59岁三组人群的物种丰富度和多样性差异都无统计学意义（均P>0.05）,基于Bray-Curtis距离的PCoA图显示三组人群的样本分布没有明显分离（相似性分析：r=0.0109,P>0.05）,LEfSe分析显示几乎没有与年龄分组有关的细菌。结论山西省健康人群的肠道菌群更倾向分为两种肠型（拟杆菌型和普氏菌型）。性别对肠道菌群组成可能没有显著影响,30-59岁人群的肠道菌群组成比较稳定     

胃癌患者肠道菌群的分布特点分析

目的 应用聚合酶链式反应－变性梯度凝胶电泳（PCR-DGGE）基因指纹图谱技术,检测胃癌患者肠道菌群的变化情况,探讨肠道菌群与胃癌发生发展的关系。方法 选取7例符合临床诊断标准的胃癌患者和相同年龄段的3例健康者的粪便标本,提取粪便总DNA。通过PCR-DGGE技术获得菌群指纹图谱,进行相似性、多样性分析。结果 胃癌患者肠道菌群与健康对照组相比,其肠道菌群构成发生显著性变化。其中,条件致病菌唾液乳杆菌、唾液链球菌、大肠埃希菌数量均增加。益生菌直肠真杆菌、Dorea longicatena、柔嫩梭菌群数量均较少。结论 胃癌患者肠道菌群的多样性和构成与健康对照相比发生了显著变化,该特点对于胃癌的预测提供了实验依据。     

降血糖药物治疗对糖尿病动物模型及患者肠道菌群的影响

随着人们生活方式和饮食结构的改变,我国糖尿病的发病率呈逐年上升趋势。如何预防并有效治疗糖尿病成为医疗工作者们重要的研究课题。目前,药物治疗是糖尿病最常用、安全以及经济的治疗手段。近年来,肠道菌群成为人们研究的焦点,越来越多证据表明它与糖尿病的发生发展存在密切的联系。本文总结了双胍类、噻唑烷二酮胰岛素增敏剂类、α糖苷酶抑制剂类、二肽基肽酶-4抑制剂(DPP-4)和胰高血糖素样肽-1(GLP-1)类似物、促胰岛素分泌剂和中药及其制剂等降血糖药物对糖尿病动物模型及患者肠道菌群的影响,以期为糖尿病的预测、预防及治疗提供参考。     

常乐康对乙肝肝硬化患者肠道菌群和肠道黏膜屏障功能的影响

目的探讨常乐康对乙肝肝硬化患者肠道菌群及肠道黏膜屏障功能的影响。方法收集乙肝肝硬化代偿期患者87例,其中治疗组48例,对照组39例。所有患者给予相同的常规护肝对症治疗,其中治疗组加用常乐康治疗8周。治疗结束后观察患者肠道菌群、肠道黏膜屏障功能和系统性炎症反应的改善情况。结果常乐康治疗后,患者肠道菌群中梭菌属I簇和XI簇及双歧杆菌属细菌数量显著升高,而肠杆菌科细菌及肠球菌属细菌数量显著降低;患者血清D-乳酸,内毒素(LPS)和二胺氧化酶(DAO)的水平显著下降,血清中促炎因子TNF-α和IFN-γ水平显著下降,而抗炎因子IL-10水平显著上升。结论常乐康可显著改善乙肝肝硬化患者肠道菌群组成和肠道黏膜屏障功能,有效减轻系统性炎症反应,可作为阻止乙肝肝硬化病情进展的有效辅助治疗方法。