彭泽鲫养殖池塘不同生境微生物基因组DNA的提取

比较3种DNA提取方法(溶菌酶法、CTAB法及珠磨法)对养殖池塘几种生境(底泥、饲料、彭泽鲫肠道内容物及肠道壁)菌群PCR-DGGE分析的影响.结果表明,以3种提取方法获得的DNA为模板均能进行16SrDNA V3区特异性片段扩增,但不同DNA提取方法对池塘不同生境菌群DGGE指纹图谱存在显著影响;人工养殖的彭泽鲫肠道内容物菌群与肠道壁的菌群存在一定的相似性,肠道内容物菌群比肠道壁菌群丰富.     

实验动物在肠道菌群与非酒精性脂肪肝病研究中的应用

非酒精性脂肪肝病(NAFLD)是一种复杂的获得性代谢应激肝损伤疾病，NAFLD的发生发展受遗传、老龄化、生活方式、饮食、中心性肥胖相关的胰岛素抵抗、代谢综合征以及肠道菌群等相关联的并行因素的影响。近年来，人们越来越重视肠道菌群在NAFLD发病机制中的作用。肠道菌群通过多个生理过程对体内肝功能有显著影响，包括能量代谢、肥胖、糖尿病和NAFLD。动物实验提供了有力的证据，表明肠道菌群失调在肥胖症和NAFLD疾病发生发展中发挥了重要作用。本文对实验动物在肠道菌群与非酒精性脂肪肝病研究中的应用进行探讨。     

乳汁菌群对6月龄婴儿肠道菌群的影响初探

目的:基于16S rRNA测序技术初步探讨有菌乳汁对产后6月龄婴儿肠道菌群的影响。方法:本研究共纳入12例产妇及其婴儿,收集产妇产后6月乳汁及其6月龄婴儿粪便标本,根据产后6月乳汁有无菌群,将乳汁分为乳汁无菌组和乳汁有菌组,比较无菌乳汁和有菌乳汁喂养6月龄婴儿肠道菌群多样性与物种差异。结果:收集的12例产后6月乳汁样本中,7例乳汁样本中检测出菌群,乳汁样本中菌群检出率58.33%。有菌乳汁喂养的6月龄婴儿肠道菌群与无菌乳汁喂养6月龄婴儿肠道菌群α多样性和β多样性无显著性差异。有菌乳汁喂养的6月龄婴儿肠道中无害芽孢梭菌、未分类丹毒丝菌科、丹毒丝菌纲、丹毒丝菌目、丹毒丝菌科的相对丰度显著高于无菌乳汁喂养6月龄婴儿(P<0.05),无菌乳汁喂养婴儿肠道中乳酸菌科、乳酸菌属的相对丰度显著高于有菌乳汁喂养的婴儿(P<0.05)。结论:产后6月乳汁中可无菌群的存在,乳汁菌群的有无虽不能改变6月龄婴儿肠道菌群的多样性,但可改变6月龄婴儿肠道菌群的菌群结构。     

影响鸡肉风味的主要因素

讨论遗传因素和环境因素两方面与鸡肉风味的关系.遗传因素主要包括:品种、性别、日龄和化学成分等;环境因素主要包括:饲料成分、饲养管理、气候以及屠宰前、屠宰中和屠宰后对肉质风味的影响.     

五种商品饲料对三种常用实验动物生长发育影响的测定

前言目前由于我国的实验动物饲料、饲养环境、饲养管理大多尚未达到科学化和标准化的阶段,特别是饲料,若想对其实际的生物学营养效价及其对实验动物生长发育的具体影响进行客观评价,尚缺少足够的科学数据。为此,我们从1990年4月至1991年2月,选用北京两个饲料厂(甲、乙)生产的五种常用饲料,对三种常用实验动物共计880只,设十     

幽门螺杆菌感染对肠道菌群的影响

 为研究幽门螺杆菌(Helicobacter pylori,Hp)感染对肠道菌群的影响,收集Hp 阴性和Hp 感染(阳性)患者的粪便标本,选择Hp 和肠道菌群中具代表性的大肠杆菌O157、乳酸杆菌、肠球菌、双歧杆菌进行PCR 扩增。实验结果表明,Hp 阴性组中未见Hp 表达,与¹³C 呼气实验结果基本一致;Hp 阴性组中乳酸杆菌、肠球菌、双歧杆菌表达较高,而Hp 感染组中3 者表达较少;Hp 阴性组中未检测到大肠杆菌O157。幽门螺杆菌感染可改变肠道菌群中乳酸杆菌、肠球菌、双歧杆菌等菌落的数量。     

浅谈实验动物全价配合饲料的品质控制

全价配合饲料是指能够满足实验动物正常生长发育、繁殖后代所需要的各种营养物质的一种混合物。实验动物本身的质量对动物试验结果影响是众所周知的 ,虽然影响实验动物的正常生长发育、繁殖后代有各方面的因素 ,但是实验动物饲料在某种程度上讲 ,具有决定性的作用。要保证实验动物的质量 ,就必须为实验动物提供高品质的全价配合饲料。全价配合饲料品质的主要影响因素有饲料原料的品质、配方设计、生产加工工艺及具体操作规程的执行、以及饲料成品储存条件。在这些因素中 ,饲料原料的品质又是最重要的 ;只有符合生产所需要的原料 ,才能将配方…     

桃核承气汤对肝性脑病大鼠肠道菌群的影响分析

摘要: 目的研究桃核承气汤对肝性脑病大鼠肠道菌群是否存在相关的影响。方法本实验对40 只SD 大鼠采用腹腔注射硫代乙酰胺( TAA) 和口腔灌胃该中药方剂汤的方法,观察大鼠的神经HE 分级和血氨的作用,以及对肠道菌群的影响。结果各剂量组不同程度地可降低大鼠HE 级别和血氨的浓度,空肠和回肠的细菌计数与模型组相比呈下降趋势且P ＜ 0. 05,对空回肠菌群具有显著的回调作用。同时各剂量组的双歧杆菌和大肠杆菌也出现回调和B/E 值增高的现象。结论该方剂汤对肝性脑病大鼠的肠道菌群具有正向的影响作用,可增加胃肠道的定植抗力作用。     

常用啮齿类实验动物寄生虫区系调查

本文报导了武汉地区某实验动物室用啮齿类实验动物寄生虫感染情况。由昆明种小鼠和BALA/c小鼠检获三种肠遭寄生蠕虫,即四翼无刺线虫(Asplculuris tetraptera)、隐藏管状线虫(Syphacia obvel-ata)和微小膜壳绦虫(Hymenolepis nana);由普通大鼠、Wistar株检获三种肠道寄生蠕虫和一条绦蚴,即微小膜壳绦虫、缩小膜壳绦虫(Hymenolepis diminuta)、鼠管状线虫(Syphacia maris)和链尾蚴(Cysticercus Fascioloris);由豚鼠检获五种肠道原虫和一种体外寄生虫,即活动豚鼠毛滴虫(Trichom-ohas caviae)、豚鼠小袋纤毛虫(Balantidium caviae)、豚鼠小唇虫(Chilomitus cavlae)、梨形杯纤毛虫(Cythodinium pirilorme)、肠唇鞭毛虫(Chilomaslix intestinalis)及豚鼠长毛虱(Gliricolaporeelli)调查结果表明,不同性别年龄动物寄生虫的感染率与感染度不同;饲养环境条件、饲养方式对感染率和感染强度有明显影响。提出改善饲养环境条件,加强饲养管理是防治动物寄生虫病,提高动物质量的重要措施。同时对危害较重的寄生虫病提出了防治意见。     

不同海拔区域内牦牛肠道菌群结构组成多样性研究

探索不同海拔牦牛肠道菌群结构组成,为不同海拔区域间牦牛的饲养交流提供帮助. 本研究随机采集海拔2 897~4 717 m的12头牦牛的新鲜粪便样本,用16s rDNA技术对样本宏基因组测定,比较分析高低海拔牦牛肠道菌群的OTU丰度差异,研究高低海拔区域的牦牛肠道微生物菌群结构组成. 结果显示,高海拔与低海拔地区牦牛肠道菌群在门、纲、目、科、属、种层面菌群结构组成不同. 高低海拔区域的牦牛肠道菌群有8个菌在属水平差异显著（P＜005）. 结果表明,高海拔与低海拔牦牛肠道菌群结构组成存在一定差异,低海拔地区牦牛肠道菌群OTU丰度比高海拔的更为丰富.     

An obesity-associated gut microbiome with increased capacity for energy harvest

The worldwide obesity epidemic is stimulating efforts to identify host and environmental factors that affect energy balance. Comparisons of the distal gut microbiota of genetically obese mice and their lean littermates, as well as those of obese and lean human volunteers have revealed that obesity is associated with changes in the relative abundance of the two dominant bacterial divisions, the Bacteroidetes and the Firmicutes. Here we demonstrate through metagenomic and biochemical analyses that these changes affect the metabolic potential of the mouse gut microbiota. Our results indicate that the obese microbiome has an increased capacity to harvest energy from the diet. Furthermore, this trait is transmissible: colonization of germ-free mice with an 'obese microbiota' results in a significantly greater increase in total body fat than colonization with a 'lean microbiota'. These results identify the gut microbiota as an additional contributing factor to the pathophysiology of obesity.     

基于16S rRNA基因扩增子测序技术研究云南野生小型哺乳动物肠道菌群多样性

以生活在同一生境,但具有不同进化关系和不同食性的野生哺乳类动物(鼠科、猬科和鼩鼱科)为研究对象,通过16S rRNA基因扩增子测序,分析和比较其肠道菌群.共识别出5378个操作分类单位(OTUs),主要隶属 Firmicutes(40.55％),Proteobacteria(34.60％)和 Bacteroidetes...     

肠道菌群的形成及影响因素研究进展

肠道菌群对人体健康具有重要作用,而年龄、饮食、抗菌药物使用和心理压力等多种因素可以影响其形成和组成。本文就相关影响因素研究进展进行综述。     

Diversity, stability and resilience of the human gut microbiota

Trillions of microbes inhabit the human intestine, forming a complex ecological community that influences normal physiology and susceptibility to disease through its collective metabolic activities and host interactions. Understanding the factors that underlie changes in the composition and function of the gut microbiota will aid in the design of therapies that target it. This goal is formidable. The gut microbiota is immensely diverse, varies between individuals and can fluctuate over time - especially during disease and early development. Viewing the microbiota from an ecological perspective could provide insight into how to promote health by targeting this microbial community in clinical treatments.     

益生菌、肠道菌群与人体健康

 肠道菌群与人体长期互作、共同进化,帮助宿主消化吸收食物中的营养物质、代谢宿主肠道中产生的有毒废物,同时产生人体必需的氨基酸、维生素、短链脂肪酸等功能物质为宿主所用。肠道菌群紊乱将导致诸如糖尿病、肠易激综合征等多种人体疾病的发生。因此,维护健康的肠道菌群平衡状态对维持机体健康十分关键。益生菌可以调节人体肠道菌群结构、抑制致病菌在肠道中的定殖,同时帮助宿主建立健康的肠黏膜保护层,增强肠道屏障作用,增强宿主的免疫系统。本文综述了乳酸菌、益生菌、人体肠道菌群的研究进展,论述了中国人群的肠道菌群特征,分析了基因型与饮食对肠道菌群的影响,指出了肠道菌群领域的研究热点及发展趋势。     

Inflammasome-mediated dysbiosis regulates progression of NAFLD and obesity

Non-alcoholic fatty liver disease (NAFLD) is the hepatic manifestation of metabolic syndrome and the leading cause of chronic liver disease in the Western world. Twenty per cent of NAFLD individuals develop chronic hepatic inflammation (non-alcoholic steatohepatitis, NASH) associated with cirrhosis, portal hypertension and hepatocellular carcinoma, yet the causes of progression from NAFLD to NASH remain obscure. Here, we show that the NLRP6 and NLRP3 inflammasomes and the effector protein IL-18 negatively regulate NAFLD/NASH progression, as well as multiple aspects of metabolic syndrome via modulation of the gut microbiota. Different mouse models reveal that inflammasome-deficiency-associated changes in the configuration of the gut microbiota are associated with exacerbated hepatic steatosis and inflammation through influx of TLR4 and TLR9 agonists into the portal circulation, leading to enhanced hepatic tumour-necrosis factor (TNF)-α expression that drives NASH progression. Furthermore, co-housing of inflammasome-deficient mice with wild-type mice results in exacerbation of hepatic steatosis and obesity. Thus, altered interactions between the gut microbiota and the host, produced by defective NLRP3 and NLRP6 inflammasome sensing, may govern the rate of progression of multiple metabolic syndrome-associated abnormalities, highlighting the central role of the microbiota in the pathogenesis of heretofore seemingly unrelated systemic auto-inflammatory and metabolic disorders.     

Tissue factor and PAR1 promote microbiota-induced intestinal vascular remodelling

The gut microbiota is a complex ecosystem that has coevolved with host physiology. Colonization of germ-free (GF) mice with a microbiota promotes increased vessel density in the small intestine, but little is known about the mechanisms involved. Tissue factor (TF) is the membrane receptor that initiates the extrinsic coagulation pathway, and it promotes developmental and tumour angiogenesis. Here we show that the gut microbiota promotes TF glycosylation associated with localization of TF on the cell surface, the activation of coagulation proteases, and phosphorylation of the TF cytoplasmic domain in the small intestine. Anti-TF treatment of colonized GF mice decreased microbiota-induced vascular remodelling and expression of the proangiogenic factor angiopoietin-1 (Ang-1) in the small intestine. Mice with a genetic deletion of the TF cytoplasmic domain or with hypomorphic TF (F3) alleles had a decreased intestinal vessel density. Coagulation proteases downstream of TF activate protease-activated receptor (PAR) signalling implicated in angiogenesis. Vessel density and phosphorylation of the cytoplasmic domain of TF were decreased in small intestine from PAR1-deficient (F2r(-/-)) but not PAR2-deficient (F2rl1(-/-)) mice, and inhibition of thrombin showed that thrombin-PAR1 signalling was upstream of TF phosphorylation. Thus, the microbiota-induced extravascular TF-PAR1 signalling loop is a novel pathway that may be modulated to influence vascular remodelling in the small intestine.     

Alterations in cecal microbiota of Jinhua piglets fostered by a Yorkshire sow

Gut microbiota health and diseases. Several play important roles in host factors, in particular antibiot- ics, affect the gut microbiota of pigs. Cross-fostering has been applied as a regular practice to equalize litter size, reduce pre-weaning mortality and increase body weight. However, the effect of cross-fostering on cecal microbiota is unclear. In this study, we fostered three Jinhua pigs to a Yorkshire sow. The fostered Jinhua piglets grew signifi- cantly faster than their biological siblings. To explore whether the cecal microbiota of piglets will alter during fostering, we characterized the cecal microbiota of allpiglets by examining the V3 hypervariable region ot 165 rDNA. We observed altered cecal microbiota in these piglets using the Illumina HiSeq 2000 platform, and this was accompanied with an increase in growth rate after fostering. The relative abundance of Bacteroidetes in the fostered Jinhua piglets was decreased compared with their biological siblings, although still higher in comparison with their new littermates. Beta-diversity analysis also showed that the cecal microbiota of the adopted Jinhua piglets differed from their biological siblings with a shift toward their step-siblings. Our data show that cecal microbiota of piglets were altered after cross-fostering while the growth rate increased.     

Metagenomic and functional analysis of hindgut microbiota of a wood-feeding higher termite

From the standpoints of both basic research and biotechnology, there is considerable interest in reaching a clearer understanding of the diversity of biological mechanisms employed during lignocellulose degradation. Globally, termites are an extremely successful group of wood-degrading organisms and are therefore important both for their roles in carbon turnover in the environment and as potential sources of biochemical catalysts for efforts aimed at converting wood into biofuels. Only recently have data supported any direct role for the symbiotic bacteria in the gut of the termite in cellulose and xylan hydrolysis. Here we use a metagenomic analysis of the bacterial community resident in the hindgut paunch of a wood-feeding 'higher' Nasutitermes species (which do not contain cellulose-fermenting protozoa) to show the presence of a large, diverse set of bacterial genes for cellulose and xylan hydrolysis. Many of these genes were expressed in vivo or had cellulase activity in vitro, and further analyses implicate spirochete and fibrobacter species in gut lignocellulose degradation. New insights into other important symbiotic functions including H2 metabolism, CO2-reductive acetogenesis and N2 fixation are also provided by this first system-wide gene analysis of a microbial community specialized towards plant lignocellulose degradation. Our results underscore how complex even a 1-microl environment can be.     

Gut microbiota composition correlates with diet and health in the elderly

Alterations in intestinal microbiota composition are associated with several chronic conditions, including obesity and inflammatory diseases. The microbiota of older people displays greater inter-individual variation than that of younger adults. Here we show that the faecal microbiota composition from 178 elderly subjects formed groups, correlating with residence location in the community, day-hospital, rehabilitation or in long-term residential care. However, clustering of subjects by diet separated them by the same residence location and microbiota groupings. The separation of microbiota composition significantly correlated with measures of frailty, co-morbidity, nutritional status, markers of inflammation and with metabolites in faecal water. The individual microbiota of people in long-stay care was significantly less diverse than that of community dwellers. Loss of community-associated microbiota correlated with increased frailty. Collectively, the data support a relationship between diet, microbiota and health status, and indicate a role for diet-driven microbiota alterations in varying rates of health decline upon ageing.