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胸腺细胞表面岩藻糖化抗原在细胞凋亡过程中变化的初步研究 总被引:3,自引:0,他引:3
细胞表面糖在细胞分化及细胞周期中均有一定的变化,而且还与细胞间的识别与信息传递有关,为了解膜表面糖复合物在细胞凋亡过程中的作用,通过地塞米松诱导小鼠胸腺细胞凋亡的模型,利用对8种抗原结构相关的寡糖特异的单克隆抗体,观察凋亡过程中胸腺细胞表面岩菏糖化糖抗原结构的变化,免疫组化的分析结果表明,正常胸腺细胞表面的糖抗原主要是含有岩藻糖基的H-2和Le^b,而凋亡的胸腺细胞表面出现GlcNAcβ1-3Ga 相似文献
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细胞表面糖在细胞分化及细胞周期中均有一定的变化,而且还与细胞间的识别与信息传递有关,为了解膜表面糖复合物在细胞凋亡过程中的作用,通过地塞米松诱导小鼠胸腺细胞凋亡为模型,利用对8种抗原结构相关的寡糖特异的单克隆抗体,观察凋亡过程中胸腺细胞表面岩藻糖化糖抗原结构的变化。免疫组化的分析结果表明:正常胸腺细胞表面的糖抗原主要是含有岩藻糖基的H-2和Le ̄b.而凋亡的胸腺细胞表面出现GlcNAcβ1-3Gal-,Galβ1-4GlcNAcβ1-3Gal-及双岩藻糖化抗原Le ̄Y,同时Le ̄b消失。磷脂提取结果表明在给药3h后膜的PS条带明显增加,通过对诱发细胞凋亡过程中组化分析的时相变化观察发现:凋亡细胞膜表面糖抗原的变化在给药1h(即凋亡发生前)就出现。以上结果说明凋亡过程中胸腺细胞表面岩藻糖化抗原发生了变化,且此变化可能与细胞凋亡的始发有关。 相似文献
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为了解子宫内膜Le^y糖蛋白在胚泡着床期间的变化,以及与胚泡表面阶段特异性Le^y抗原出现的关系,应用对Le^y寡糖特的AH-6单抗为探针,通过SDS-PAGE和Westernblot免疫酶标染色,观察了小鼠子宫内膜Le^y糖蛋白在着床期的动态变化和分布特点,结果表明:(1)未孕及着床前后的小鼠子宫内膜均含Le^y糖蛋白Mr50~200kD,未孕内膜的含量明显高于着床期间的样品;(2)在着床日(D 相似文献
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人肝癌中Lewis抗原,α1,3岩藻糖转移酶与转移倾向 总被引:9,自引:0,他引:9
为了测定人原发性肝癌中Lewis抗原和α1,3岩灌糖转移酶(FucT)亚型的表达,及其与癌栓形成和转移抑制基因nm23-H1表达的关系,用免疫组化法测Lewis抗原,用Northern印迹法测FucT和NM23-H1的mRNA。结果表明,肝癌组织中SLe^x、Le^x、SDLe^x、SLe^a4和Lewis抗原表达的 率均在80%左右。其中SLe^x表达较多,Le^x和SLe^a较少,SDLe^x 相似文献
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^3H-TdR放射性转化细胞经1×10^-5mol/L Foskolin处理24h后,TGFa,c-myc,c-K-ras基因的mRNA表达下降;TGFβ,c-fos基因表达无明显变化。非转化细胞经相同条件处理,TGFa,TGFβ,c-myc及c-K-ras基因表达无显著改变。提示:Forskolin介导的转化细胞的生长抑制作用与TGFa,c-myc,c-K-ras基因的转录表达下降有关。 相似文献
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为探讨肿瘤转移与细胞表面的糖结构的关系,对小鼠肝癌细胞的高、低淋巴道转移株Hca-F和Hca-P进行了蛋白质电泳及经蛋白质印迹术后的5种凝集素(ConA、WGA、UEA、SBA、PNA)结合糖蛋白谱的对比分析.结果表明:高、低转移两株细胞的SDS-PAGE谱基本相同;ConA特异结合糖蛋白共有5种(~72,80~90,~104,~150,~200kD);其中较明显的差异为~72kDConA特异结合糖蛋白,它在Hca-P细胞的表达明显高于Hca-F细胞.WGA特异结合糖蛋白1种(~150kD),在Hca-P细胞的表达略高于Hca-F细胞.此外,实验发现两种性质未明的蛋白质(~79,~130kD),后者在Hca-P细胞的含量明显高于Hca-P细胞.结果提示Hca-F和Hca-P细胞不同的转移表型可能与其糖蛋白的表达有一定的关联. 相似文献
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为了解子宫内膜Le~y糖蛋白在胚泡着床期间的变化,以及与胚泡表面阶段特异性Le~y抗原出现的关系,应用对Le~y寡糖特异的AH-6单抗为探针,通过SDS-PAGE和Westernblot免疫酶标染色,观察了小鼠子宫内膜Le~y糖蛋白在着床期的动态变化和分布特点。结果表明:(1)未孕及着床前后的小鼠子宫内膜均含Le~y糖蛋白Mr50~200kD),未孕内膜的含量明显高于着床期间的样品;(2)在着床日(D4)样品可见微量16kD的Le~y糖蛋白条带;(3)未孕至D4的子宫内膜均有Le~y糖蛋白分泌至宫腔,但呈渐减趋势,未孕样品Le~y糖蛋白主要为分泌型,而D4样品Le~y糖蛋白主要存在于子宫内膜,宫腔液含量很少;结果提示子宫内膜Le~y糖蛋白在着床期间具有含量、组成和分布上的动态变化,这些变化可能与胚泡着床以及胚泡在宫腔内其表面Le~y糖抗原转为阳性密切有关。 相似文献
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人血管内皮细胞生长因子受体Flt—1胞外区cDNA在毕赤酵母中的?… 总被引:2,自引:0,他引:2
将编码血管内皮细胞生长因子受体FIt-1胞外区1-3loop316个氨基酸残基的cDNA插入到含AOX1启动子和α分泌信号肽序列的Pichia pastoris酵母载体中,构建了重组表达质粒pPIC9K/FIt=1(1-3),转化酵母景菌GS115,筛选His^+Mut^s表型转化子,经插瓶培养,1%甲醇诱导表达4d后,SDS-PAGE结果显示,培养上清中FIt-1(1-3)表达这总蛋白的30-% 相似文献
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根据拟南芥(arabidopsisthahliana)GPA1的保守区段A设计一对特异引物(5′ctggggaatctggaaaatc3′,5′cacagctgtacacctcaaac3′)通过PCR从丝瓜核基因组中扩增植物的三聚体G蛋白α亚基编码基因,获得了2个片段(LFG1,LFG2),并已克隆和测序(已在EMBL数据库中登记,登记号为:y15270,y15271).序列分析表明LFG1和LFG2分别由1515bp和732bp构成,都含有三聚体G蛋白α亚基编码基因的保守区段A,但也都含有内含子.根据片段的大小及PCR的特性,LFG1可能是丝瓜三聚体G蛋白α亚基编码基因上的片段. 相似文献
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胰岛素样生长因子Ⅱ对大鼠离体培养黄体细胞孕酮生成的影响 总被引:1,自引:0,他引:1
本实验观察了胰岛素样生长因子Ⅱ(IGF-Ⅱ)对大鼠离体培养黄体细胞孕酮生长的影响,并对其作用机制进行了探讨。结果显示,IGF-Ⅱ能显著地促进大鼠离体培养黄体细胞孕酮生成并呈剂量-效应关系,同时还能促进^3H-亮氨酸掺入黄体细胞蛋白质的合成,促进^3H-胸腺嘧啶掺入DNA的合成,而上述效应分别被放线菌酮(CYX)和放线菌素D所抑制。此外,IGF-Ⅱ对大鼠离体黄体细胞内泊性cAMP和hCG诱导的cAM 相似文献
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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. 相似文献
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RICHARD E. NORRIS 《Botanical journal of the Linnean Society. Linnean Society of London》1991,106(1):1-40
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. 相似文献
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JOAN VALUÈS MONTSERRAT TORRELL NÚRIA GARCIA JACAS 《Botanical journal of the Linnean Society. Linnean Society of London》2001,137(4):399-407
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. 相似文献
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肝癌中HBV和HCV基因和抗原的分布及意义 总被引:1,自引:0,他引:1
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 相似文献
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H.-R. GREGORIUS 《Biological journal of the Linnean Society. Linnean Society of London》1984,23(2-3):157-165
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. 相似文献
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. 相似文献