Fmr1基因敲除型小鼠肠道菌群结构分析

目的探讨Fmr1基因敲除型小鼠粪便肠道细菌群落的结构及多样性。 方法利用16S rRNA高通量测序技术对10份小鼠粪便样本进行测序分析并进行生物学分析。 结果两组样本测序共获得高质量序列325 280条，核心菌门为拟杆菌门、厚壁菌门、变形菌门。Anosim分析表明基因敲除(KO)组与正常野生型(WT)组小鼠两组间具有显著差异，组内样品重复性满足数据分析要求，Adonis分析表明本次检验可信度高(P<0.05)。LDA值展现KO组与WT组小鼠肠道微生态菌群有明显差异，基于Unifrac距离，Amova分析表明KO和WT组组间差异显著(P<0.05)。 结论KO组与WT组小鼠肠道微生物群落的结构及多样性存在显著差异且具有统计学意义，提示孤独症与肠道微生态系统密切相关，肠道微生态系统可能通过微生物代谢的间接作用影响孤独症的发生发展，但具体的作用机制仍需进一步的研究。     

结直肠癌发生与肠道菌群的相关性研究

目的 探索结直肠癌发生与肠道菌群的相关性。方法 分别收集在四川地区长期生活的33例结直肠癌患者（结直肠癌组）和33例健康人群（对照组）的粪便,采用16S rRNA测序分析比较两组人群粪便肠道菌群差异。结果 结直肠癌组患者Shannon指数较健康人低（P<0.05）,而ACE指数、Chao指数、Observed species指数和Simpson指数均无统计学差异（P>0.05）。在门水平上结直肠癌组患者厚壁菌门（P<0.001）、放线菌门（P<0.01）降低,梭杆菌门（P<0.01）、疣状菌门（P<0.01）升高。在属水平上结直肠癌组患者毛螺菌属、瘤胃球菌、粪球菌、霍氏真杆菌等相对丰度降低（P<0.01或0.05）,UBA1819、毛螺菌科UCG.010、副拟杆菌属、另枝菌属等相对丰度升高（P<0.01或0.05）。属水平肠道菌群与血红蛋白的相关性分析显示,结直肠癌组患者多尔菌属与血红蛋白呈负相关。结论 四川地区结直肠癌患者肠道菌群多样性减少,呈现有益菌较少、有害菌增多的特征,其发生可能与副拟杆菌属、另枝菌属、颤螺科UCG.002等有关。...     

孕早期蔬菜和水果摄入与肠道菌群的关系

目的 探讨成都市孕早期妇女蔬菜和水果摄入与肠道菌群组成及多样性之间的关系。方法 本研究纳入104例成都市孕早期妇女,使用膳食频率问卷收集其蔬菜和水果摄入情况,并分别依据蔬菜、水果摄入量中位数将孕早期妇女分为摄入量高组和摄入量低组。使用16S r RNA高通量测序检测孕早期妇女粪便样本肠道菌群,比较组间肠道菌群差异。采用多重线性回归探讨蔬菜、水果摄入和孕早期妇女肠道菌群的关系。结果 孕早期妇女蔬菜和水果摄入量中位数分别是90.0 g/d和200.0 g/d。孕早期蔬菜、水果摄入高低组孕早期妇女肠道菌群α多样性和β多样性无统计学差异。LEfSe分析显示,孕早期妇女多个肠道菌群的相对丰度在蔬菜、水果摄入量高低组间存在显著差异（P<0.01）。多重线性回归分析显示,在调整了年龄、孕前体质指数和能量摄入后,孕早期妇女蔬菜摄入量与Eubacterium siraeum group相对丰度呈正比（β=0.007, P=0.012）,与Bacteroides相对丰度呈反比（β=-0.167, P=0.023）;水果摄入量与Ruminococcus gnavus group相对丰度呈正比（β=0....     

孕前和孕期高脂饲料喂养对新生大鼠肠道菌群的影响

目的 探讨孕前和孕期高脂饲料喂养对新生大鼠肠道菌群的影响。方法 12只3周龄无特定病原体(Specific Pathogen Free, SPF)级雌性Sprague-dawley(SD)大鼠,适应性喂养一周后,按体重随机分为对照组与高脂组,孕前分别用基础饲料与高脂饲料喂养至12周龄,与同周龄SPF级雄性SD大鼠合笼,次日观察到阴道栓或阴道涂片中发现精子后,判定受孕。孕鼠单笼饲养,孕期的饲料与孕前相同。收集出生后第0.5天(postnatal day 0.5,PD 0.5)仔鼠,称量体重,采集肠道组织并称量质量,计算肠道系数;进行回肠和结肠组织病理和相关基因检测;提取肠道内容物的细菌总DNA,通过16S rRNA测序分析肠道菌群。采用t检验或Mann-Whitney U检验分析数据。结果 与对照组相比,高脂组PD 0.5仔鼠体重、肠道质量、肠道系数无显著改变(t=-0.682,P=0.499;t=0.269,P=0.790;t=0.674,P=0.506);肠道病理形态无改变;结肠闭合蛋白-1(Claudin-1)、溶菌酶(Lysozyme)、再生胰岛衍生蛋白3伽马(regenerat...     

母亲孕晚期肠道菌群与婴儿食物过敏的关系

目的 探讨母亲孕晚期肠道菌群与婴儿食物过敏的关系,为微生物与食物过敏的关系提供新方向。方法 本研究为巢式病例-对照研究,选取2018年2月—2020年5月在北京大学第三医院妇产科规律产检的健康孕妇与其分娩的新生儿建立母婴队列,其中有135对母婴符合入排标准并规律随访,根据婴儿1岁以内是否出现食物过敏分为食物过敏(FA)组24对和健康对照(HC)组44对。收集母亲分娩前2周内的粪便标本以及婴儿生后5个不同时间点的粪便标本。采用16S rDNA基因测序对粪便标本进行微生物学分析。结果 FA组和HC组相比,母亲孕晚期肠道菌群在α多样性和β多样性上差异均无统计学意义(P>0.05)。HC组较FA组母亲晚期肠道菌群中霍尔德曼菌属(Z＝-2.103,P=0.035)相对丰度升高,而梭菌属ⅪⅤa群(Z＝-2.483,P=0.013)、梭菌属Ⅳ群(Z＝-2.154,P=0.031)、乳球菌属(Z＝-2.147,P=0.032)和细小单胞菌属(Z＝-2.377,P=0.017)相对丰度降低,差异均具有统计学意义。母亲孕晚期肠道菌群的主要菌属和差异菌属在婴儿肠道菌群中,在同一时间点上的差异无统计学意义(P>0.05)。结论 母亲孕晚期肠道菌群中的霍尔德曼菌属相对丰度水平为子代婴儿食物过敏的潜在预测指标,且与子代婴儿肠道菌群中该菌的相对丰度水平无关。母体肠道菌群对后代食物过敏的影响机制有待进一步研究。     

非酒精性脂肪肝与肠道菌群及益生菌的相关性研究进展

摘要:非酒精性脂肪肝是一种代谢性疾病,其发病机制复杂。肠道菌群在非酒精性脂肪肝的发生及发展过程中起着重要的作用。而益生菌作为调节肠道菌群的有效手段,可以通过降低肠道内毒素水平,提高肠道黏膜屏障,减轻全身炎症反应等多种机制对非酒精性脂肪肝起到预防和改善作用。本文就近年来肠道菌群和非酒精性脂肪肝的相关性以及益生菌的调节作用作一综述,为今后的研究应用提供依据。     

噪声暴露对大鼠肠道菌群结构的影响及功能预测

[背景]噪声对机体产生多种负面影响,肠道菌群受环境影响并与疾病的发生密切相关.目前关于长期噪声暴露对肠道菌群的影响知之甚少.[目的]研究旨在探究噪声暴露对大鼠肠道菌群结构的影响,并进行菌群功能预测.[方法]雄性Wistar大鼠(6周龄,160～180 g)被随机分为对照、95 dB噪声暴露(NE_95dB)组和105 ...     

不同喂养方式对婴儿肠道菌群的影响

【目的】　通过观察健康婴儿母乳及配方乳两种不同喂养方式下肠道菌群的定植过程 ,分析婴幼儿饮食与肠道菌群形成的关系并探讨其意义。　【方法】　采用荧光定量PCR技术测定细菌 16SrRNA ,经与标准曲线对照计算细菌数量 ,对 71名母乳喂养婴儿和 60名人工喂养婴儿粪便中乳酸杆菌、双歧杆菌和大肠杆菌进行了定量检测。　【结果】　婴儿肠道菌群处于动态定植过程。母乳喂养婴儿肠道乳酸杆菌、双歧杆菌数量较人工喂养婴儿高 (P<0 .0 5 ) ,而大肠杆菌数量较人工喂养婴儿低 (P <0 .0 5 )。　【结论】　荧光定量PCR法定量测定肠道菌群的数量是一种简便、快捷、特异性好的方法。婴儿期肠道菌群仍处于动态演替过程。不同的喂养方式对肠道菌群有影响 ,应大力提倡母乳喂养。     

妊娠期糖尿病对3月龄婴儿肠道菌群影响的前瞻性队列研究

目的 比较妊娠期糖尿病(gestational diabetes mellitus, GDM)及正常孕妇的3月龄婴儿肠道菌群的差异,探讨妊娠糖尿病对后代肠道菌群的影响。方法 数据来自中国母婴营养与健康队列,将2016年6月—2019年12月在河北省某县产检、分娩并随访至产后3个月的母亲及婴儿纳入研究,孕中期或孕晚期空腹血糖检测值≥5.1 mmol/L的孕妇及其婴儿纳入GDM组。采集3月龄婴儿粪便,采用16S rDNA高通量测序技术对所有粪便样本进行检测,了解两组肠道菌群分布特点。结果 共纳入48对研究对象,GDM组16对,对照组32对。肠道菌群多样性比较：Alpha多样性指数分析,GDM组Observed Species指数(141.4±17.2)低于对照组(154.9±21.7),margalef指数(13.66±1.66)低于对照组(15.00±2.11),menhinick指数(0.83±0.10)低于对照组(0.91±0.13)(P<0.05)。菌落结构比较：在门水平上GDM组厚壁菌门(Firmicutes)、拟杆菌门(Bacteroidetes)、放线菌门(Actino...     

Influence of soya-based infant formula consumption on isoflavone and gut microflora metabolite concentrations in urine and on faecal microflora composition and metabolic activity in infants and children

The urinary excretion of soya isoflavones and gut microflora metabolites was investigated in infants and children who had been fed soya-based infant formulas in early infancy. These infants and children were compared with cows'-milk formula-fed controls, to determine at what age gut microflora metabolism of daidzein to equol and/or O-desmethylangolensin (O-DMA) was established, and whether exposure to isoflavones in early infancy influences their metabolism at a later stage of development. Sixty infants and children (aged 4 months-7 years) participated in the study; thirty in each of the soya and control groups. There were four age groups. These were: 4-6 months (seven in the soya group and seven in the control group); 7-12 months (seven in the soya group and nine in the control group); 1-3 years (six in the soya group and eight in the control group); 3-7 years (ten in the soya group and six in the control group). Urine samples were collected to measure isoflavonoids by MS, and faecal samples were collected to measure gut-health-related bacterial composition, by fluorescent in situ hybridisation with oligonucleotide probes, and metabolic activity. A soya challenge (typically a soya yoghurt alternative product containing 4.8 g soya protein and on average 22 mg total isoflavones) was given to control-group infants (>6 months) and children, and also to soya-group children that were no longer consuming soya, to determine their ability to produce equol and/or O-DMA. Urinary genistein, daidzein and glycitein were detected in all infants (4-6 months) fed soya-based infant formula; O-DMA was detected in 75 % of infants but equol was detected in only 25 %. In the controls (4-6 months), urinary isoflavonoids were very low or not detected. In the older age groups (7 months-7 years), O-DMA was found in the urine samples of 75 % of the soya group and 50 % of the controls, after the soya challenge. Equol excretion was detected in 19 % of the soya-group infants and children, and in only 5 % of the controls. However, in the oldest (3-7 years) children, the proportion excreting O-DMA and equol was similar in both groups. Faecal bacterial numbers for bifidobacteria (P<0.001), bacteroides and clostridia (P<0.05) were significantly lower for the soya group compared with the control group. There appears to be no lasting effect of early-life isoflavone exposure on isoflavone metabolism.     

肠道菌群在小鼠术后焦虑样行为中的作用研究

目的:探究腹部手术后焦虑与肠道菌群紊乱之间的关系.方法:将16只C57BL/6J小鼠随机分为实验组(n=8)和对照组(n=8),实验组小鼠行腹部切开,对照组小鼠无任何处理.术后第7天收取小鼠粪便,术后第15天收取小鼠肝脏,肠道等组织,期间记录两组小鼠的体质量,自主活动、认知及焦虑抑郁情况.分析肠道菌群差异,并与术后焦虑...     

Morphometrical parameters of gut microflora in human volunteers

The morphology of faecal microflora of nine healthy human volunteers was studied by digital image analysis of microscopic slides. Weekly specimens were collected during an 8-week period. Seven morphometrical parameters were derived: the means and medians of components 1, 2 and 3, and morphometrical entropy. Statistically significant differences among subjects were found for means of components 1 and 2, medians of components 1, 2 and 3, and entropy. The stability in normal circumstances provides an excellent basis for the detection of pathological change in gut flora balance.     

The influence of the gut microflora and of dietary fibre on epithelial cell migration in the chick intestine

1. The renewal of the intestinal mucosal epithelium has been investigated in germ-free and conventional chicks given a practical chick diet and a low- and high-fibre diet, using tritiated thymidine to label the nuclei of mucosal cells undergoing division. 2. Villus height, crypt depth and number of mitoses in the crypt were generally, although not always significantly, greater for conventional chicks than for germ-free chicks at all sites investigated in the intestine, and all became progressively lower from the upper intestine to the lower intestine. 3. There was a linear relationship between the height of the radioactively labelled mucosal cells on the villus and the period after injection, and the rates of epithelial cell migration were higher for conventional than for germ-free chicks, the relative differences being greater in the lower intestine than the upper intestine. 4. The inclusion of wheat bran as a source of dietary fibre had no effect on the rate of epithelial renewal, either in germ-free or conventional birds.     

Chlorogenic acid bioavailability largely depends on its metabolism by the gut microflora in rats

Chlorogenic acid, the ester of caffeic acid with quinic acid, is one of the most abundant polyphenols in the human diet with coffee, fruits and vegetables as its major sources. Its antioxidant and anticarcinogenic properties have been well established in animal studies. However, little is known about its gut absorption and metabolism. In the present work, four groups of rats (n = 8) were fed a diet supplemented with chlorogenic, caffeic or quinic acids (250 micromol/d) or an unsupplemented diet for 8 d. Parent compounds and their metabolites were estimated in urine (24-h collection) and plasma by HPLC-electrospray ionization-tandem mass spectrometry. Significant differences in their levels were observed among the groups. The recovery of chlorogenic acid in urine was low (0.8%, mol/mol), and the total urinary excretion of caffeic acid liberated by hydrolysis of chlorogenic acid and its tissular methylated metabolites (ferulic and isoferulic acids) did not account for >0.5% (mol/mol) of the dose ingested. On the other hand, the metabolites of microbial origin, namely, m-coumaric acid and derivatives of phenylpropionic, benzoic and hippuric acids, represented the major compounds in both urine and plasma. Hippuric acid largely originated from the transformation of the quinic acid moiety, and all other metabolites from the caffeic acid moiety. These microbial metabolites accounted for 57.4% (mol/mol) of the chlorogenic acid intake. Such a high abundance of microbial metabolites shows that the bioavailability of chlorogenic acid depends largely on its metabolism by the gut microflora. Their potential importance in explaining the biological effects of dietary polyphenols is emphasized.     

婴儿早期不同喂养方式对体格生长的影响

目的：探讨不同喂养方式对婴儿体格生长的影响。方法选择出生、42 d、9个月时有完整的体重、身长数据,且生后～9个月喂养方式单一的婴儿304例,随访到18个月时有243例婴儿。按喂养方式分为母乳喂养、混合喂养和配方奶喂养组。计算18个月婴儿BMI对年龄Z评分（BAZ）并绘图。对不同喂养组的身长、体重及其增长量,BAZ分布进行比较。结果3组出生时体重、身长差异无统计学意义。42 d 时母乳喂养组体重[（5.0±0.5）kg]高于配方奶喂养组[（4.9±0.6）kg];出生～42 d母乳喂养组体重增长量[（1.7±0.4）kg]高于混合喂养组[（1.5±0.4）kg]和配方奶喂养组[（1.4±0.4）kg];42 d～9个月母乳喂养组体重增长量[（4.5±1.0）kg]低于混合喂养组[（4.8±0.8）kg]和配方奶喂养组[（5.1±1.1）kg];18个月时配方奶喂养组体重[（12.1±1.5）kg]高于母乳喂养组[（11.2±1.4）kg];9～18个月配方奶喂养组体重增长量[（2.3±0.8）kg]高于母乳喂养组[（1.8±0.7）kg]和混合喂养组[（1.9±0.5）kg];42 d～9个月配方奶喂养组身长增长量[（17.1±2.0）cm]高于母乳喂养组[（16.1±1.9）cm];18个月时配方奶喂养组身长[（83.1±3.7）cm]大于母乳喂养组[（81.5±2.9）cm];差异均有统计学意义。18月时配方奶喂养婴儿中超重（即Z评分大于2）的比例最高,为11.11％。结论3种喂养方式婴儿体重增长模式不同。早期母乳喂养的婴儿体重增长较快,配方奶喂养后期体重增长较快。不同喂养方式对婴儿早期的身长增长无影响,配方奶喂养的婴儿后期身长增长较快。配方奶喂养的婴儿18个月超重的比例最高。