超排处理对雌兔生殖器官中表皮生长因子表达的影响

本研究采用免疫荧光组织化学染色法和蛋白免疫印迹法比较研究了后肢去负荷大鼠(Rattus norvegicus)和冬眠不活动达乌尔黄鼠(Spermophilus dauricus)不同类型骨骼肌氧化应激水平和抗氧化防御能力及与肌萎缩之间的关系。结果显示,后肢去负荷14 d后,大鼠比目鱼肌和趾长伸肌肌萎缩程度显著升高,过氧化氢和丙二醛水平增加,Nrf2介导的抗氧化信号通路及下游抗氧化酶蛋白表达及活性显著下降;而冬眠不活动达乌尔黄鼠骨骼肌中肌萎缩指标并未出现变化,氧化应激水平维持夏季组水平,抗氧化酶和调控因子出现不同程度升高。研究表明,后肢去负荷导致非冬眠大鼠骨骼肌氧化应激水平升高,抗氧化防御能力减弱,可能是导致大鼠废用性肌萎缩的重要机制之一;而冬眠动物达乌尔黄鼠骨骼肌在自然废用状态下,抗氧化防御能力增强可能是防止自然冬眠不活动引起的废用性肌萎缩的重要机制。     

冬眠哺乳动物氧化应激产生及抗氧化防御机制研究进展

哺乳动物的冬眠是一种季节性异温状态,是对外界恶劣自然环境的一种适应策略。冬眠-阵间觉醒周期中,伴随着生理功能的剧烈变化,从冬眠期间整体代谢的抑制,到阵间觉醒时氧代谢的急剧增加,使动物体内产生了大量的氧自由基。然而,冬眠动物出眠时并未表现出明显的氧化损伤迹象,因此,冬眠哺乳动物被认为是一种天然的抗氧化损伤模型。本文从氧化应激的产生、活性氧的来源、抗氧化防御等方面综述了冬眠哺乳动物对氧化应激的防御,并从其抗氧化的分子调控方面分析了冬眠哺乳动物对氧化应激的适应机制。     

折翼蝠冬眠期几项生理常数的测定及分析

折翼蝠(Miniopterus schreibersii chinensis Thomas)在皖南地区数量较多、分布较广,是哺乳类中具冬眠习性的异温动物。这种异温动物的生理生态研究,国内极少报道。我们于1981年10月至1982年5月对折翼蝠冬眠期的几项生理常数做了测定和分析,目的在于了解它们在冬眠期间的生理变化及其与外界环境因子之间的相互关系,从而进一步探讨异温动物冬眠期的代谢规律,为休眠的理论和动物资源的利用提供一点参考资料。     

骨骼肌失神经萎缩的细胞分子生物学研究进展

周围神经损伤后,骨骼肌因神经的营养作用丧失及自身废用而发生萎缩,出现一系列形态结构、生理生化及代谢功能等方面的改变。而神经损伤后,骨骼肌萎缩的防治一直是周围神经外科的一大难题,当骨骼肌萎缩发展到不可逆阶段将导致神经修复手术的失败。因此,进一步探索不同时段失神经后萎缩肌肉的形态结构、生理、生化变化以及它们之间的相互关系,为寻找检测肌肉萎缩程度的方法和更好的防治具有重要临床意义。     

肌肉生长抑制素调控动物骨骼肌生长机制的研究进展

肌肉生成抑制素（myostatin, MSTN）在动物机体骨骼肌的增殖、分化和生长中起着重要的负调控作用。MSTN基因的过表达会阻碍骨骼肌增殖分化及生长发育,而缺失或表达降低则会导致肌肉肥大,形成双肌现象（double muscle phenomenon, DMP）。MSTN能作用于多个基因及结合多种细胞因子广泛参与生理生化、物质代谢、病理调控等过程,在动物机体生长发育过程中扮演着重要的角色。本文将从MSTN基因的历史渊源、基因定位、时空表达特性、部分相关作用机制等方面进行论述,旨在对MSTN调控动物骨骼肌生长部分机制作梳理,以期为后期研究提供理论依据。     

运动对骨骼肌基因表达的表观遗传调控作用

DNA甲基化、组蛋白修饰和miRNA表达调控是表观遗传调控的3种重要方式,其在基因表达调控中发挥着关键作用。适当运动有益于身心健康。骨骼肌作为运动的主体组织,运动可以提高其代谢能力,改善其线粒体生物学功能,调控肌纤维类型转化,增加骨骼肌力量。近年来越来越多的研究表明,表观遗传调控在机体适应运动过程中发挥着重要作用,DNA甲基化、组蛋白修饰和miRNA表达调控等表观遗传调控方式通过调控骨骼肌基因表达来改变骨骼肌代谢能力、线粒体生物学功能和肌纤维类型,从而适应运动变化。本文对近年来运动对骨骼肌基因DNA甲基化、组蛋白修饰和相应miRNA表达调控等3种表观遗传调控方式的研究现状进行了综述,以期为进一步研究运动改善机体机能和健康提供参考。     

无蹼壁虎冬眠期的生态及形态生理研究

本文观察研究了无蹼壁虎冬眠期的生态和形态生理状况。冬眠期无蹼壁虎喜在墙缝及岩缝中过冬。冬眠对体长和尾长无影响,而其体重显著减少。冬眠期温度的变化与冬眠活动关系密切。经过冬眠,其肥满度、脂肪体系数、肝系数平均明显减少,变化非常显著,而生殖腺系数的变化不显著。冬眠前雌性组肝脏和脂肪体的均重都大于雄性组。     

冬眠和非冬眠状态达乌尔黄鼠肾单位及相关功能因子的比较

冬眠是动物应对冬季低温和食物匮乏的一种生存策略。达乌尔黄鼠 (Spermophilus dauricus) 是典型的贮脂类冬眠动物。为研究冬眠动物肾脏的适应机制,本实验采用组织学、血液生化分析及酶联免疫方法检测了夏季活动期 (7月) 、冬眠期 (12月) 和早春出眠后 (3月) 达乌尔黄鼠肾单位形态学及血清肌酐、尿素和抗利尿激素 (ADH) 的变化,并用qPCR方法检测了肾脏水通道蛋白基因 (AQP1、AQP2和AQP3)、ADH受体 (V2R) 及内皮型一氧化氮合酶基因 (eNOS) 的表达。结果发现,冬眠期和早春出眠期的达乌尔黄鼠肾小球密度、近曲小管和远曲小管的相对管径、皮质部近曲小管数与远曲小管数比值均低于夏季活动期;冬眠期血清肌酐和尿素浓度高于夏季活动期和早春出眠期,ADH浓度及其受体V2R基因表达低于夏季活动期;冬眠期AQP1基因表达高于早春出眠期,AQP3基因表达低于夏季活动期,AQP2基因表达无显著差异;冬眠期eNOS基因表达低于早春出眠期。这些结果表明冬眠的达乌尔黄鼠表现出较低的肾功能;不同时期的水通道蛋白,eNOS及ADH表现出适应性的功能调节。该实验结果丰富了对冬眠动物肾脏适应机制的认识。     

冬眠与免疫

免疫系统是机体防御机制的重要组份。冬眠季节,冬眠动物免疫系统的结构退化、机能抑制,与动物整体的活动相适应,春季恢复。综述民哺乳动物中枢与外周淋巴器官和免疫反应的季节性变化。对调控免疫系统变化的环境因素和受环境因素影响的内源性生理节律对免疫系统冬眠季节的抑制机理作了介绍,更从冬眠对免疫的抑制联系到冬眠净化机体内外环境、冬眠与肿瘤、冬眠与辐射乃至冬眠与长寿等临床关心的实验研究作了简要介绍。     

线粒体在运动诱导骨骼肌适应过程中的应答机制

运动训练通过诱导骨骼肌适应提高运动机能和健康水平。在此过程中,线粒体具有显著的可塑性,不断地重塑自身的网络结构,并对骨骼肌收缩所引发的一系列信号刺激做出相应的应答反应,以适应骨骼肌对代谢的需求。当线粒体功能失调时,机体通过特定的细胞内系统对这类线粒体进行清除及再利用。因此,运动适应过程中线粒体的应答包括线粒体数量和质量的协同调控。本文着重关注骨骼肌适应中的线粒体质量控制应答,并总结目前对运动调节这些应答机制的理解。     

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.     

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.     

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