Nulp1基因抑制P19CL6细胞向心肌细胞分化

Nulp1基因是已克隆的一个新的bHLH转录因子亚家族成员.前期的研究表明：Nulp1蛋白作为一个转录抑制子对SRF信号途径有极强的抑制作用.为了进一步研究Nulp1基因在心肌分化中的作用,在能够高效分化为心肌细胞的P19CL6细胞系中过表达Nulp1基因,发现心肌分化标志基因的表达被抑制;用RNA干扰技术,使Nulp1基因在P19CL6细胞系中的内源表达降低,发现心肌分化标志基因的表达提高,说明Nulp1基因能够抑制P19CL6细胞系向心肌细胞的分化.     

GFRAL,新发现的GDF-15受体

<正>生长分化因子-15(growth/differentiation factor 15,GDF-15)是转化生长因子-β(transforming growth factor beta,TGF-β)超家族成员,亦称为巨噬细胞抑制因子-1(macrophage inhibitory cytokine-1,MIC-1)。GDF-15有丰富的生物多效性,参与多种疾病进程:其在心肌梗死期,可抑制心肌细胞凋亡,保护心肌;在动脉粥样硬化晚期,能抑制斑块增大;在肿瘤发生过程中,GDF-15水平升高,发挥抗炎和抗细胞凋亡作用;此外,GDF-15还参与代谢过程,并表现出优化代谢的效应,如减少摄食量、降低肥胖、     

癌变组织特异高表达抗凋亡蛋白——ARC

带有caspase富集功能域的凋亡抑制因子（ apoptosis repressor with a caspase recuitment domain, ARC ）是新近发现的重要抗凋亡蛋白。在正常组织中,ARC高度特异地表达在终末分化组织如心肌、骨骼肌和大脑,而在非终末分化组织不表达或微量表达。但是,当非终末分化组织发生癌变时表达大量的ARC。ARC过表达可以抑制阿霉素或射线诱导的癌细胞死亡,提示ARC在癌细胞中具有抗趋化或抗放射线损伤的作用。因此,ARC可能成为一种新的肿瘤标记物,也可能是决定肿瘤对各种治疗方法反应性的一个重要因素。     

血浆鸢尾素、生长分化因子-8在老年肌肉减少症患者中的表达及其诊断价值分析

摘要 目的：分析血浆鸢尾素、生长分化因子-8在老年肌肉减少症患者中的表达及其诊断价值。方法：选择2020年4月至2022年4月在我院接受体检的620例老年体检者作为研究对象,其中238例肌肉减少症者作为观察组,382例非肌肉减少症者作为对照组。检测两组血浆鸢尾素、生长分化因子-8表达水平,观察血浆鸢尾素、生长分化因子-8在不同严重程度的老年肌肉减少症患者中差异性,使用Pearson相关性分析血浆鸢尾素、生长分化因子-8与全身骨骼肌质量、四肢骨骼肌质量、相对骨骼肌指数、握力和步速的关系,通过ROC下面积（AUC）评价血浆鸢尾素、生长分化因子-8对老年肌肉减少症的诊断效能。结果：观察组血浆鸢尾素表达水平低于对照组,生长分化因子-8表达水平高于对照组（P＜0.05）;肌肉减少症前期、肌肉减少症期、重度肌肉减少症期的患者血浆鸢尾素表达水平依次降低,生长分化因子-8表达水平依次升高（P＜0.05）;经Pearson相关性分析,老年肌肉减少症患者全身骨骼肌质量、四肢骨骼肌质量、相对骨骼肌指数、握力和步速均与子鸢尾素呈正相关(P＜0.05),与生长分化因子-8呈负相关（P＜0.05）;经ROC曲线分析,血浆鸢尾素、生长分化因子-8诊断老年肌肉减少症的敏感度为78.49 %,特异度为90.67 %,AUC为0.914。结论：老年肌肉减少症患者血浆鸢尾素表达明显下调、生长分化因子-8表达明显上调,两者与病情严重程度密切相关,联合诊断此病的效能较好,值得临床予以重视应用。     

GDF15基因在卵巢上皮性癌组织中的表达及其临床意义

目的:探讨生长分化因子GDF15(Growth Differentiation Factor 15)基因在卵巢上皮性癌组织中的表达及其与铂类耐药的相关性。方法:应用免疫组化、western blot、RT-PCR等方法对80例原发性卵巢癌组织和卵巢癌顺铂敏感/耐药株A2780和CP70、SKOV3和SKOV3/DDP中生长分化因子GDF15表达水平进行测定。结果:生长分化因子GDF15的表达强度与卵巢癌铂类耐药性显著相关。在卵巢癌顺铂耐药株CP70、SKOV3/DDP中GDF15表达水平较顺铂敏感株A2780、SKOV3明显增高。结论:GDF15表达水平与卵巢癌发生发展及铂类耐药相关,对于卵巢癌患者早期筛选、预测预后具有一定的临床指导价值。     

ARC的生理与病理生理意义

ARC全称是带有caspase富集功能域的凋亡抑制因子(apoptosis repressor with a caspase recruitment domain)。在正常状态下,ARC高度特异地表达是在终末分化组织如心肌、骨骼肌和大脑,而在非终末分化组织不表达或微量表达。在病理状态下,ARC在心肌、骨骼肌和神经系统损伤中发挥重要作用;在非终末分化组织来源的癌细胞系中高度表达,并呈组织差异性,因此ARC是一个新的肿瘤标记物。     

生长分化因子-15在肥胖、糖尿病及心血管疾病中的作用

生长分化因子-15(growth differentiation factor-15,GDF-15),又称巨噬细胞抑制因子-1,是转化生长因子-β(transforming growth factor-β,TGF-β)家族的一个应激反应细胞因子,在产前发育、炎症、应激反应以及急性损伤后的组织修复中起关键作用.GDF-1...     

分化抑制因子3的表达调控机理及其功能

分化抑制因子3（inhibitor of differentiation 3,Id3）属于螺旋-环-螺旋（helix-loop-helix,HLH）转录因子家族成员之一,该分子参与细胞周期调控过程,在细胞生长与发育、机体的生理及病理过程中发挥重要调控作用。其表达和功能涉及许多复杂的调控机制。     

分化抑制因子3的表达调控机理及其功能

分化抑制因子3(inhibitor of differentiation 3,Id3)属于螺旋-环-螺旋(helix-loop-helix,HLH)转录因子家族成员之一,该分子参与细胞周期调控过程,在细胞生长与发育.机体的生理及病理过程中发挥重要调控作用.其表达和功能涉及许多复杂的调控机制.     

hhlim对心肌肥大的影响及其作用机制探讨

hhlim是从胎儿心脏中新近分离和克隆得到的与心脏发生相关的基因,其表达产物作为转录因子参与多种基因的转录调控和细胞的发育与分化过程.用细胞转染方法将外源性hhlim基因导入原代心肌细胞,发现该基因强制性表达可使心肌细胞体积明显增大.RT-PCR和蛋白质印迹结果表明,hhlim促心肌细胞肥大与诱导α-肌动蛋白(α-actin)过表达及重新启动胚胎期表达基因脑钠肽（BNP）表达有关.用可表达hhlim反义RNA的真核表达载体转染心肌细胞后,致心肌细胞肥大因子ET-1对BNP和α-actin表达的诱导受到显著抑制.这些结果表明,ET-1促进BNP和α-actin表达及引发心肌肥大的效应可能由hhlim所介导,提示hhlim表达与心肌细胞肥大的启动有关.单独或共转染转录因子hhlim、Nkx2.5、GATA-4表达质粒和BNP转录调控区指导的报告基因结果显示,hhlim强制性表达不仅能直接激活BNP基因表达,而且与NKx2.5具有协同作用.结果表明,hhlim可以通过直接或与Nkx2.5协同作用激活BNP基因的表达.     

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.