肠道菌群与孤独症发病关系的研究进展

肠道菌群与人体的健康或疾病状态息息相关,在营养摄取、免疫与内分泌调节、药物代谢中都起着重要的作用,并能通过微生物群-肠-脑轴影响中枢神经系统的发育与功能。流行病学数据显示,肠道菌群的组成变化与多种中枢系统疾病相关。其中,孤独症是一类以社交障碍、刻板行为、兴趣狭隘为主要临床特征的神经发育障碍性疾病。由于孤独症与胃肠道疾病之间联系紧密且其发病率正逐年上升,人们愈发关注肠道菌群在孤独症发病过程中的作用。研究发现,肠道菌群能够影响孤独症患者的中枢神经系统发育,导致异常的行为表现并诱发胃肠症状等。本文总结了影响肠道菌群组成的因素,并从微生物群-肠-脑轴的角度讨论了肠道菌群影响孤独症的方式,同时介绍了孤独症患者肠道菌群疗法的有效性与临床前景。     

肠道菌群和黄疸的研究进展

新生儿黄疸是一种常见的临床问题,80%以上的新生儿出生后会出现黄疸。大部分黄疸是需要临床进一步干预和治疗的,否则严重的并发症可导致终身残疾。目前,随着肠道菌群与疾病关系的探讨逐渐深入,对肠道菌群与疾病关系的研究已成为热门话题。肠道菌群通过免疫、神经和代谢等多种途径影响儿童的发育和健康。益生菌可以调节肠道微生物环境,因此为预防及改善黄疸提供新的思路。本文就肠道菌群在黄疸中的作用、肠道菌群与黄疸及相关疾病的关系和益生菌在黄疸中应用的最新进展进行综述。     

儿童肠道菌群的建立及影响因素研究进展

早期肠道菌群的建立与机体长远的健康状况密切相关,儿童肠道菌群具有动态、脆弱的特点,孕期菌群暴露、出生途径、喂养方式、出生环境、抗生素使用以及添加益生菌等多种因素均可影响其形成和功能;本文就相关影响因素研究进展进行综述.     

影响新生儿肠道细菌定植相关因素的研究进展

胃肠道内源菌群组成了人体内最大的微生物环境,它构成复杂,种类繁多,并且与人类的疾病和健康息息相关。同时新生儿阶段是建立肠道微生态系统的关键时期。对于新生儿来讲,肠道细菌定植过程中发生的异常可以提高许多疾病的发病风险。近年来国内外学者对新生儿肠道细菌定植状况及其影响因素进行了深入的临床和基础研究并取得了一定的进展。本文对影响生命早期肠道微生态系统建立和发展的主要因素进行系统地阐述,这些影响因素包括孕妇的口腔卫生、分娩时间、喂养方式、分娩方式、抗生素的使用以及益生菌的应用等。     

肠道菌群与婴幼儿体重的研究进展

肥胖已成为全球急需解决的公共健康问题之一。新生儿体重过重伴随着易患各种感染性疾病和造成孕妇分娩困难等问题。另外,婴幼儿超重在儿童期和成年期更容易发生超重和肥胖问题。近年来,大量研究对肠道菌群与肥胖之间的调节和作用关系,以及影响肠道菌群组成的因素进行了深入的探索。本文主要从我国新生儿肥胖现状及其危害,肠道菌群与肥胖的关系,婴幼儿肥胖与影响肠道菌群组成的饮食、抗生素等因素之间的关系等多个方面综述肠道菌群与体重的最新进展,为预防婴幼儿肥胖提供有效依据。     

肠道菌群与精神分裂症的研究进展

精神分裂症是一种精神障碍疾病。除了遗传因素外,一些环境因素也参与了精神分裂症的发生,肠道微生物群是近年来发现的主要影响因素之一。研究表明,精神分裂症患者肠道菌群普遍发生了紊乱,肠道菌群通过肠-脑轴影响神经功能和疾病。肠道菌群可以通过影响神经系统发育、免疫和代谢功能来诱导精神分裂症的发生,肠道菌群可能是精神分裂症防治的有效靶点,调节肠道菌群可能是防治精神分裂症的一种潜在方法。本文就精神分裂症的易感因素、肠道菌群在精神分裂症中的作用、机制以及防治策略等方面的研究进展进行综述。     

孕妇肠道菌群与婴幼儿肠道菌群及肥胖的关系研究进展

女性妊娠过程中,身体的生殖、消化、内分泌等系统会发生一系列变化,孕妇的肠道菌群也会发生相应变化。母亲肠道菌群与子代肠道菌群密切相关,婴幼儿生命早期肠道菌群的来源主要有母亲肠道菌群、母亲阴道菌群和母亲体表菌群,出生以后婴幼儿肠道菌群的定殖主要受喂养方式、生活环境、抗生素暴露等因素的影响。此外,人体肠道菌群功能强大,其可通过调节人体营养物质吸收和外周器官的代谢而成为影响肥胖的一种重要的内环境因素。综述孕妇妊娠期间包括孕早期、孕中期、孕晚期肠道菌群的变化和影响婴幼儿肠道菌群定殖的主要因素,以及对子代肥胖的影响,以期为临床医务人员对预防和控制婴幼儿肥胖提供参考。     

肠道菌群与神经精神疾病

人体肠道中存在着数量庞大和种类繁多的细菌,这些细菌及其代谢产物在代谢、免疫、内分泌、神经等方面起着重要作用,对于人类的健康有着重要影响。近年来越来越多的研究表明,正常的肠道菌群在维持大脑的发育与功能方面扮演着重要角色,而肠道菌群的失调与一些神经精神疾病密切相关,例如帕金森症、多发性硬化、抑郁、自闭症等。本文就肠道菌群与神经精神疾病的关系作一综述。     

肠道菌群影响因素的研究进展

肠道菌群是动物体内最复杂、最庞大的微生态系统,其多样性和组成在调节宿主的健康、生理、发育和环境适应等方面具有不可替代的作用.肠道菌群受多种因素的综合影响.综述宿主遗传因素、食物和高海拔环境对肠道菌群的影响.     

肠道菌群与中枢神经系统相互作用及相关疾病

肠道菌群参与宿主的多项生理过程,包括营养物质吸收、代谢及免疫系统的发育成熟、抵抗外来病原体入侵等,新的研究显示肠道菌群通过神经、内分泌、代谢和免疫的途径参与了肠道和中枢神经系统的双向调节。肠道菌群的变化与自闭症、多发性硬化、帕金森病、焦虑和抑郁症等一系列神经精神疾病有关,通过改善肠道菌群的微生态疗法有望成为治疗和预防一些神经系统疾病的有效措施。     

A Unique Protease Cleavage Site Predicted in the Spike Protein of the Novel Pneumonia Coronavirus (2019-nCoV) Potentially Related to Viral Transmissibility

正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases     

Curcuminoids as inhibitors of thioredoxin reductase: A receptor based pharmacophore study with distance mapping of the active site

Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.     

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     

Comparative morphology of the carpel in the Liliaceae: Hewardieae, Petrosavieae, and Tricyrteae

The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle.