雌激素受体参与疼痛调控的研究进展

雌激素受体属转录因子核受体超家族成员。雌激素受体的两个亚型ERα和ERβ都有类似于核受体超家族成员的调节结构,介导雌激素参与生理和病理过程中的多种效应。ERα和ERβ广泛分布于神经系统中疼痛调节相关的区域,大量动物实验及临床研究资料证实ERα和ERβ参与急、慢性疼痛的调控。本文拟对雌激素受体的特性及其在疼痛调控中的作用予以阐述。     

雌激素受体β亚型

1996年发现雌激素受体存在亚型,即ERβ。ERβ与ERα结构相似。广泛分布于多种组织内,其表达受体激素的影响但不依赖于ERα,并与组织分化、发育过程相关。ERβ可能在生殖系统和神经系统中发挥重要作用,还可能参与肿瘤发生与进展过程ERβ与ERα在体内分布、与配体亲和力、促转录活性上存在差异,对ERβ及其特异性配体的进一步研究具有重要意义。     

雌激素受体β与乳腺癌

雌激素受体β(ERβ)与雌激素受体α(ERα)的结构相似,是一类配体调节的转录因子,属于核受体超家族,分布于乳腺等多种组织中,具有重要的生理病理学意义。本文简要综述雌激素受体β的基因结构、剪接变体、转录调节机制及其在乳腺癌发生发展、治疗预后和抗雌激素耐受中的意义。     

雌激素受体亚型及其配体调节基因转录机制的研究

本文综述雌激素受体亚型（ERα和ERβ）的结构,功能,组织分布,生理作用及雌激素受体配体调节基因转录的机制,目的是深入系统地了解植物雌激素和选择性雌激素受体调节剂的作用路径及其组织特异性的发生机制,最终为提高雌激素类药物的选择性,优化以临床为基础的药物设计提供一条较为系统的思路。结果表明,ERα和ERβ对不同雌激素类化合物产生不同应答,配体的结构不同,调节基因转录的路径不同和募集的辅调节蛋白的不同是雌激素受体两种亚型组织特异性激活或抑制的主要原因。     

植物雌激素与乳腺癌发病发展的研究进展

总结植物雌激素(phytoestrogen,PE)在乳腺癌发病、发展过程中的研究进展。应用Medline、Embase、CNKI及VIP数据库检索"植物雌激素、乳腺癌"相关基础临床试验流行病学调查。PE作为非甾体结构的雌激素类似物,能够与雌激素受体结合产生作用。目前研究主要集中于PE通过雌激素受体对乳腺癌细胞的增殖、凋亡、自噬、周期的影响和信号传导通路的研究,体外实验PE有抑制乳腺癌细胞增殖、促进凋亡、自噬的作用,但是对转移的作用不明确,可通过PI3K/AKT和ROS/p38MAPK途径诱导凋亡,PE与ER结合或调整ERα/ERβ达到抑制乳腺癌细胞的作用,流行病学调查未发现PE对人体有害,鲜有临床报道。因此,本文对PE对乳腺癌的研究进展进行总结分析,旨在为乳腺肿瘤患者治疗提供新方向。植物雌激素有希望成为乳腺肿瘤患者治疗的新方向。     

雌激素及其受体对不同年龄段神经系统作用的研究进展

雌激素的新近研究发现,雌激素的功能并不局限于生殖系统,它也能够通过其广泛分布的受体（ERα和ERβ）影响神经系统的发育与功能,且该作用受年龄的影响。本文综述了雌激素对发育期、青年期、更年期三个年龄段神经系统功能状态的影响。在发育期,雌激素影响神经细胞的存活和生长,与其神经保护作用有关;青年期其主要与情绪变化关系密切,该阶段不同诱因的抑郁和精神障碍的发生即与雌激素在体内水平变化有关;同时雌激素与其受体的水平变化对于更年期妇女AD发生,骨质损坏和绝经后抑郁也有一定的作用。了解对神经系统发育存活影响作用的机制,有利于在不同生命阶段的神经系统疾病治疗过程中采取相应的策略,达到更佳的治疗效果。     

雌激素相关受体 ERR 的功能及其调控

雌激素相关受体 (estrogen -related receptor , ERR) 属于核受体超家族,是第一个发现的孤儿核受体,包括 ERRα, ERRβ和 ERRγ . ERR 的生物学功能主要体现在以不同的方式参与雌激素信号途径, ERR 与雌激素受体 (estrogen receptor , ER) 在骨骼组织和乳腺组织中拥有共同的靶基因,其中 ERRα和 ERRγ的表达状况还可作为乳腺癌诊断标志 . 另外, ERR 还在代谢调控中起重要作用 . 由于至今未在体内找到 ERR 的小分子配体,因而找到 ERR 活性调节因子对理解与雌激素相关的疾病如骨质疏松症、乳腺癌和糖尿病等将是非常有用的 .     

泛素-蛋白酶体途径对雌激素受体α降解的调控

泛素-蛋白酶体途径是真核细胞内降解蛋白质的重要途径,对于维持细胞的正常功能起着重要作用。雌激素受体α(ERα)作为转录因子,与乳腺癌的发生及进展关系密切,抑制ERα的功能已经成为治疗乳腺癌的主要策略之一。目前发现泛素-蛋白酶体途径能够促进ERα降解,影响其转录。简要综述了泛素-蛋白酶体途径对雌激素受体α的转录及降解调控的研究进展。     

雌激素受体β共调节因子的研究进展

雌激素受体(ER)包括α和β等2种,均为核受体。ERβ在乳腺癌预后和激素治疗耐受中有重要意义,其活性受与之相互作用的共调节因子的影响。这些共调节因子有的能与2种ER发生作用,有的只能特异地作用于其中一种。本文简要综述了与ERβ相互作用的共调节因子的相关研究进展。     

α-雌激素受体介导的膜信号转导通路

近年来关于α-雌激素受体(ERα)介导的雌激素膜信号转导成为研究热点。ERα介导的雌激素膜信号转导通路,主要包括一氧化氮信号通路、钙离子信号通路以及蛋白激酶信号通路。这些信号转导过程中有第二信使的动员、ERα与连接蛋白的结合,非受体蛋白激酶的活化、ERα与其他膜蛋白的相互作用等多种细胞事件的参与。阐明ERα在雌激素非基因组信号转导中的作用及机制,对于开发更有效的选择性雌激素受体调节剂、改善肿瘤内分泌治疗效果,具有重要临床意义。     

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.