关于儿童粪菌移植技术规范的共识

正正常成人胃肠道菌群有1 000余种,总量达1013-14[1],10倍于人体细胞总量,人体正常肠道菌群的基因总和是人体自身基因的100~150倍[2]。肠道是人体最大的消化器官,同时也是最大的免疫器官和代谢器官。儿童肠道菌群的定植与建立对出生后消化系统、免疫系统和代谢等发育和成熟具有重大作用。肠道菌群紊乱与感染性疾病、免疫性疾病和代谢性疾病的发生和发展具有密切的关系。近5年来,粪菌移     

益生菌制剂对脑卒中患者肠道菌群及肠道功能影响的Meta分析

目的探讨益生菌制剂对脑卒中患者肠道菌群及肠道功能的影响。方法通过检索PubMed、EMbase、Cochrane Library、CNKI、维普和万方数据库,收集各数据库从建库至2020年3月发表的所有关于脑卒中患者应用益生菌制剂的随机对照试验,由2名研究者独立筛选文献,按照系统评价的要求对文献质量进行评估,使用RevMan 5.3和Stata 14.0统计软件进行Meta分析。结果共纳入19篇文献(1 528例患者),Meta分析结果显示,2组患者肠道中肠球菌的数量差异没有统计学意义[SMD=-0.74,95%CI(-1.64,0.17),P=0.110],而益生菌组患者肠道中大肠埃希菌的数量低于对照组[SMD=-1.27,95%CI(-1.81,-0.73),P0.001];益生菌组患者肠道中乳杆菌和双歧杆菌数量高于对照组[SMD=1.50,95%CI(0.96,2.03),P0.001;SMD=1.66,95%CI(1.16,2.15),P0.001]。益生菌组患者血清中二胺氧化酶(DAO)和D-乳酸水平低于对照组[SMD=-1.76,95%CI(-2.39,-1.13),P0.001;SMD=-2.21,95%CI(-2.92,-1.51),P0.001];益生菌组患者粪便中分泌型免疫球蛋白A(sIgA)的量高于对照组[SMD=1.76,95%CI(0.84,2.68),P0.001]。结论在肠内营养的基础上添加益生菌制剂对脑卒中患者进行营养治疗,能够有效调节患者肠道菌群,改善患者的肠道功能。     

头低位卧床期间人体肠道益生菌多样性变化

目的观察了解头低位卧床期间人体肠道益生菌双歧杆菌属、乳酸杆菌属的数量及多样性的变化趋势。方法采集受试者-6°头低位连续卧床30d期间肠道便样,通过平板可培养技术、浓度梯度凝胶电泳技术和Ion Torrent基因组测序技术平台等实验方法,检测分析肠道粪便益生菌。结果卧床期间,可培养肠道菌群中的双歧杆菌、乳杆菌数量显著减少,益生菌中双歧杆菌出现不规律的缺失与恢复,肠道菌群多样性指数下降。结论头低位卧床期间肠道益生菌多样性发生了改变。益生菌数量减少,多样性指数下降,头低位卧床对肠道菌群有不利的影响。     

昂立1号~益生菌颗粒调节肠道菌群作用的研究

目的研究昂立1号益生菌颗粒调节肠道菌群作用。方法依照《保健食品检验与评价技术规范-2003版》之"调节肠道菌群作用检验方法"。结果该益生菌颗粒产品在30 d动物实验和14 d人体试验中,双歧杆菌和乳杆菌数量均有显著增加。结论该益生菌产品具有调节肠道菌群的保健作用。     

益生菌制剂治疗内毒素肝损害研究进展

内毒素是肝病发生、发展和恶化的最重要原因 ,可以直接或间接地造成肝脏的损害 [1 - 3]。有的学者认为内毒素是各种原因肝损害的共同物质基础 [4] 。因此 ,许多研究者试图通过某些改变或降低内毒素的方法来减轻肝损害。传统常用的药物治疗效果并不十分令人满意 ,近年有人提出用微生态疗法 ,即补充益生菌或益生元制剂作为肝病的辅助治疗 ,本文对此做一综述。1　益生菌制剂的概念及治疗原则益生菌是对人体有益无害的细菌 ,又称活菌剂。 1979年Fuller将其定义为能够促进肠道菌群生态平衡 ,对人体起有益作用的活的微生物制剂。目前最常用的乳酸…     

双歧杆菌的研究进展

双歧杆菌是人类最早发现的生理性细菌之一。双歧杆菌是能在健康人肠道内定植的益生菌 ,母乳喂养的婴儿肠道内该菌占总菌群的 92 %以上 ,现在已确认双歧杆菌是人体健康的重要标志之一 [1 ] 。双歧杆菌在健康成年人及长寿老人的胃肠道内是优势菌 ,当机体患病或衰老时肠道双歧杆菌较正常人少 [2 ] ,其数量随年龄变化呈动态变化趋势 ,并与许多生理、病理现象密切相关 ,因此引起了医学领域内专家们的广泛关注。国内针对双歧杆菌曾多次召开微生态学术讨论会 ,在国际上 ,1990年在日本举行国际双歧杆菌专题讨论会 ,对双歧杆菌的生理、生化、分类、作…     

肠道共生微生物与免疫

人体肠道内负载着一个由多种微生物组成的复杂的微生物群落。据初步估计,人肠道内的微生物包含有1 000多个种类,数量可以达到1014,大约是人体自身细胞数量的10倍,其编码的基因是人体自身基因数目的100倍。在长期的共进化过程中,这个复杂的微生物群落广泛参与了寄主身体各个方面的调节,包括代谢、生理、营养等。近40年来的研究显示,肠道菌群和免疫系统紧密相连,特别是近些年来的研究表明,肠道菌群对免疫稳态的建立和免疫系统功能的正常发挥起着重要作用。临床和动物实验结果都表明免疫相关的疾病比如炎性肠病(inflammatory bowel disease,IBD)、癌症、糖尿病、过敏及肥胖都可能与肠道菌群的失衡相关。本文将从肠道菌群对肠道局部免疫系统和全身免疫系统两个方面通过动物实验和临床研究来阐述肠道微生物对免疫系统发育、功能及相关疾病的影响。     

肠道细菌易位

人体肠道中有数百个种群、约 10 1 2 ～ 10 1 3 个细菌 ,重量可达 1公斤左右 ,这些细菌存在于特定的空间及时间 ,在数量上维持一定的比例 ,与人体相互依存 ,构成了人体肠道微生态系统。正常情况下 ,肠道细菌与机体处于动态平衡状态 ,一旦这一状态遭到破坏 ,就造成微生态失衡 ,表现为细菌种群数量及比例上的改变 (菌群失调 )或 /和细菌空间上的转移(移位或易位 ) ,导致各种疾病的发生及发展。肠道菌群失调在临床上较为常见 ,已广泛被人们认识 ,采用益生菌制剂防治也取得了显著的效果。而对肠道细菌易位的认识相对缓慢 ,可喜的是近十余年来 ,…     

人体肠道乳杆菌的最新研究进展

乳杆菌是健康人体肠道的重要菌群之一,它与肠道微生态系统的调节和代谢、免疫的调控密切相关。大多数乳杆菌对人类健康有积极作用,其中一部分已被归为益生菌。一直以来,乳杆菌在人体中的存在状态和作用机制都是肠道微生态领域的研究重点。本文总结了人体肠道乳杆菌在种类、数量和功能方面的最新进展,值得注意的是,基于现代分子生物学技术的研究发现乳杆菌在人体肠道菌群中所占的数量比例相当小。虽然在数量上不占优势,但在对宿主生理功能的影响和代谢过程的调节上有不可替代的作用。此外本文还讨论了该领域仍需研究的内容,为人们进一步探索提供一些帮助。     

肠道益生菌预防和治疗食物过敏的研究进展

目前 ,食物过敏的发生率在人群 ,尤其是婴幼儿中逐年增高。其治疗策略仍是以排除致敏食物为主 ,但效果欠佳。由于益生菌所独有的生物学特点和肠道粘膜免疫反应的特异性 ,使肠道益生菌疗法作为治疗食物过敏的一种新兴疗法 ,日益受到人体的重视。本文就其临床疗效、作用机制、选菌原则、使用安全性等问题作一综述 ,以期加强对益生菌的研究和应用。1　益生菌治疗食物过敏的疗效研究进展益生菌在人体中主要以双歧杆菌和乳酸杆菌为主 ,具有粘附肠粘膜、稳定胆汁酸、使用安全 ,是人类肠道共生细菌等共同特点。作为肠道微生态的平衡者和肠道粘膜免…     

Recent advances in the study of Kaposi's sarcoma-associated herpesvirus replication and pathogenesis

It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.     

The structure, reproduction and taxonomy of Vidalia and Osmundaria (Rhodophyta, Rhodomelaceae)

Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.     

New or rare chromosome counts in Artemisia L. (Asteraceae, Anthemideae) and related genera from Kazakhstan

Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.     

肝癌中HBV和HCV基因和抗原的分布及意义

采用原位分子杂交方法检测HCV RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细     

Selection with two alleles and complete dominance

For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.