SLE患者PBMC凋亡状态及相关基因表达的研究

探讨外周血单个核细胞(PBMC)凋亡及其基因调控在系统性红斑狼疮(systemic lupus erythematosus,SLE)发病机制中的作用.用流式细胞仪(FCM)检测PBMC凋亡百分率及T细胞亚群的凋亡状态;用RT-PCR检测PBMC bcl-2和bax的mRNA表达;用FCM检测凋亡相关基因bcl-2,bax,fas,p53和c-myc的蛋白表达.结果显示,SLE患者PBMC凋亡百分率明显高于正常人,且活动期患者高于非活动期患者.SLE活动期患者CD4+,CD8+T细胞数明显低于正常人;非活动期患者CD8+T细胞数明显低于正常人,而CD4+T细胞数与正常人比较无统计学差异;SLE患者PBMC bcl-2和bax mRNA表达与正常人比较无统计学差异;SLE患者PBMC bcl-2,bax和fas蛋白表达明显高于正常人,p53和c-myc蛋白表达在各组之间无统计学差异.SLE患者PBMC凋亡百分率增高、外周血T细胞亚群的异常及bcl-2,bax和fas蛋白表达增高,在SLE发病机制中可能起了一定的作用.     

刺五加多糖诱导人小细胞肺癌H446 细胞凋亡

研究刺五加多糖(Acanthopanax senticosus polysaccharide,ASPS)诱导H446细胞凋亡及其可能的作用机制.采用MTT法检测ASPS对小细胞肺癌H446细胞增殖的抑制作用;Hoechst 33258染色和流式细胞技术检测经ASPS处理后H446细胞凋亡的形态特征及凋亡率的变化;West ern印迹方法检测凋亡相关基因bax、bcl-2、p53 表达的变化.MTT分析表明,ASPS作用48 h后可明显抑制H446细胞的增殖,半数抑制浓度(IC50值)为476.36 mg/ml;Hoechst 染色结果: H446细胞在ASPS诱导下出现典型的凋亡形态;流式细胞术检测结果显示: 对照组及浓度为240、480、960 mg/ml 药物处理组凋亡率分别是(5.02±0.4)%、(11.12±0.8)%、(19.89±0.5)%、(22.54±0.8)%;Western印迹显示: 在ASPS的诱导下bax、p53的表达量提高,而bcl-2的表达量下降.研究表明,ASPS对H446细胞增殖有抑制作用,并能促进其凋亡;ASPS通过上调bax、 p53表达,下调bcl-2表达促进H446细胞凋亡.     

Ad-IL-24对人胶质瘤细胞生长抑制效应的体外实验

研究携带人白介素24(IL-24)的腺病毒表达载体(Ad-IL-24)对人U251胶质瘤细胞生长的影响和抗肿瘤分子机制。将不同MOI Ad-IL-24感染U251人胶质瘤细胞后, MTT法检测Ad-IL-24对U251细胞生长的抑制作用, 流式细胞仪和Hochest 染色法检测细胞的凋亡率。RT-PCR检测bcl-2、bax、ICE、C-myc、HIF-1a和p53等基因的转录表达水平, Western blotting检测Cleaved Caspase-3的表达。结果表明100 MOI Ad-IL-24感染U251细胞后能明显抑制细胞生长, 并能明显诱导细胞凋亡, 感染72 h后细胞凋亡率可达42%, 感染4 d后细胞生长抑制率可达50%。RT-PCR检测发现Ad-IL-24能引起与细胞凋亡和血管形成相关基因bax/bcl-2、ICE、C-myc、p53的上调和HIF-1a的下调, 并促进Caspase-3的活化。本研究结果显示Ad-IL-24能明显抑制人胶质瘤细胞U251生长和诱导细胞凋亡, 其抗肿瘤机制可能与通过bax/ bcl-2、ICE、c-myc、p53的上调和HIF-1a的下调, 进而导致Caspase-3的活化而诱导肿瘤细胞发生凋亡有关。     

非何杰金恶性淋巴瘤的PCNA及其凋亡调控基因的表达

为探讨非何杰金恶性淋巴瘤（NHL）的细胞增殖及共与凋亡调控基因bcl-2、bax表达状态之间的关系。利用免疫组化方法检测了62例NHL中的PCNA、P53、bcl-2及bax基因蛋白的表达水平。结果显示随着NHL恶性程度的逐增,PCNA、P53及bcl-2蛋白的表达率、表达强度及其阳性细胞密度逐渐增高,低度恶性组明显低于中度及高度恶性组（P＜0.01）;而bax蛋白的表达情况则相反,低度恶性组显高于中度及高度恶性组（P＜0.01）;但它们四在中度及高度恶性组的表达均无统计学意义（P＞0.050。提示NHL中不仅存在大量的增殖细胞,而且还伴有细胞凋亡调控的异常,细胞增殖与凋亡的失衡在NHL发生发展中可能起重要作用。     

bc1-2和bax及NF-kB在白藜芦醇诱导肝癌细胞凋亡中的作用

目的探讨白藜芦醇诱导肝癌细胞凋亡的途径.方法白藜芦醇体外处理HepG2肝癌细胞24 h后,以免疫组化检测凋亡调控基因bcl-2和bax及NF-kB的表达.结果白藜芦醇处理组HepG2细胞bcl-2的阳性积分和NF-kB的阳性细胞密度均明显低于对照组(P＜0.01);而bax阳性积分明显高于对照组(P＜0.01).结论白藜芦醇能下调HepG2细胞bcl-2基因的表达,上调bax的表达,同时抑制NF-kB的活化,这可能是其诱导HepG2细胞凋亡的途径之一.     

白藜芦醇对猪前体脂肪细胞凋亡的作用及机理

旨在研究白藜芦醇对猪前体脂肪细胞凋亡的作用,探讨其分子机制。以50 μmol/L、100 μmol/L、200 μmol/L、400 μmol/L白藜芦醇处理猪前体脂肪细胞,采用Hoechst 33258染色剂染色,光学和荧光显微镜分别观察细胞的形态学变化。semi-qRT-PCR和Western blotting方法检测凋亡相关基因sirt1、caspase-3、bcl-2、bax、p53、NF-κB的mRNA和蛋白的表达变化。结果表明,白藜芦醇处理后,前体脂肪细胞出现明显的细胞凋亡,伴随细胞体积缩小,染色质凝集,核质固缩等特征显现,与对照组相比200 μmol/L处理组细胞的凋亡率显著升高 (P＜0.05)。凋亡相关基因sirt1、caspase-3和bax的mRNA和蛋白表达水平显著上调 (P＜0.05),而bcl-2、p53、NF-κB等基因的表达水平明显下调 (P＜0.05)。进一步证实白藜芦醇特异性地增加sirt1的表达活性,而sirt1的上调影响caspase-3和bcl-2家族因子的活性,同时参与调控p53和NF-κB的转录表达。因此,推测sirt1调控凋亡相关因子表达是白藜芦醇诱导前体脂肪细胞凋亡的关键原因。     

西酞普兰对慢性应激大鼠额叶皮质神经细胞bax mRNA、bcl-2 mRNA表达及凋亡的影响

目的:探讨西酞普兰对慢性应激大鼠的额叶皮质神经细胞bax、bcl-2 mRNA表达的影响。方法:取24只雄性SD大鼠随机分为对照组(不进行任何处理)、应激组(应激+生理盐水灌胃)、实验组(应激+西酞普兰灌胃),采用强迫游泳制造慢性应激模型(15 min/d,共4周),用原位杂交技术检测bax、bcl-2 mRNA表达情况,TUNEL法检测细胞凋亡,尼康图像分析(NIS DR)软件测量各指标阳性细胞数量。结果:应激组较对照组,大鼠额叶皮质bax mRNA阳性表达细胞明显增多(P0.01)、染色加深;bcl-2 mRNA阳性表达细胞明显减少(P0.01)且染色变浅,且TUNEL阳性细胞数量增多(P0.01),染色增强。而实验组较应激组大鼠,额叶皮质bax mRNA阳性表达细胞减少(P0.01)、染色变浅,bcl-2 mRNA阳性表达细胞明显增多(P0.05),染色加深,且TUNEL阳性细胞数量减少(P0.01),染色减弱。结论:大鼠额叶皮质神经细胞bax mRNA和bcl-2 mRNA的表达水平受到慢性应激的影响,导致细胞凋亡加剧,西酞普兰能够有效调控额叶皮质神经细胞bax和bcl-2 mRNA的表达水平,拮抗细胞凋亡,这可能是西酞普兰防治慢性应激引起的神经精神疾病的相关机制之一。     

新生牛牛脑活性肽NBBP-1对人神经母细胞瘤SK-N-SH细胞增殖和相关基因表达的影响

目的:应用新生牛牛脑活性肽NBBP-1处理人神经母细胞瘤SK-N-SH细胞,观察NBBP-1对人神经母细胞瘤SK-N-SH细胞增殖和相关基因表达的影响.方法:通过细胞计数、流式细胞仪、光学显微镜、免疫细胞化学方法检测细胞的变化.结果:经60μg/mL NBBP-1处理后,SK-N-SH细胞生长抑制率高达90.09%,细胞周期被阻滞在G0/G1,细胞核裂解成多个,免疫细胞化学染色结果显示,经处理后bcl-2抗凋亡基因蛋白表达减弱,而p53、fas、bax等促凋亡基因蛋白表达增强.结论:新生牛牛脑活性肽NBBP-1对人神经母细胞瘤SK-N-SH细胞凋亡具有显著的诱导作用,其诱导癌细胞凋亡的机理与其调节和干预癌基因bcl-2和p53、fas、bax等抑癌基因的表达有关.     

大蒜多糖对中毒性心肌炎心肌细胞凋亡的影响

目的:研究大蒜多糖 (GP)对中毒性心肌炎心肌细胞凋亡及Bcl -2、Bax蛋白表达的影响,探讨GP抑制心肌细胞凋亡的可能机制。方法:建立小鼠阿霉素 (ADR)中毒性心肌炎模型,利用缺口末端标记法检测心肌凋亡细胞;免疫组化法检测心肌细胞bcl 2、bax基因的蛋白表达情况,并利用电镜观察心肌结构变化。结果:ADR( 3mgkg-1ip,qod× 7)可致小鼠心肌细胞凋亡数明显升高,心肌细胞线粒体水肿,促进心肌细胞凋亡蛋白bax和抑制细胞凋亡蛋白bcl 2含量均明显升高,但bax/ bcl- 2的比值同时升高明显,与正常组比较有显著差异性 (P <0 . 0 1 )。GP可逆转ADR所致的上述改变,表现为剂量依赖性抑制细胞凋亡,降低bax蛋白表达同时增加bcl 2表达,使bcl- 2/ bax的比值增加 (P <0 .0 5或P <0 . 0 1 )。结论:GP能拮抗阿霉素所致的小鼠中毒性心肌炎心肌细胞凋亡作用,其作用机制可能与抑制Bax基因的蛋白表达,使Bcl -2基因表达的蛋白功能相对增强,Bcl -2 /Bax比值升高有关。     

NF-κB、p53和bax在顺铂所致肾损伤中的作用

目的探讨NF-κB抑制剂吡咯烷二硫代氨基甲酸盐(PDTC)和顺铂治疗对Lewis肺癌小鼠肾脏组织中p53和bax表达的影响。方法给小鼠皮下接种Lewis肺癌细胞用顺铂和/或PDTC治疗,15 d后处死小鼠。取肾脏并制成切片,应用免疫组织化学技术检测p53和bax蛋白的表达。结果对照组和PDTC组小鼠肾脏未检测到p53和bax表达;顺铂治疗小鼠肾小管上皮细胞表达p53和bax;合用PDTC治疗组小鼠p53和表达水平较单用顺铂治疗组明显减低。结论合用PDTC下调顺铂诱导的p53和bax表达上调,减少肾细胞凋亡。     

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.