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1.
α1,2-岩藻糖转移酶基因转染对卵巢癌细胞生物学行为的影响 总被引:3,自引:0,他引:3
为探讨α1,2-岩藻糖转移酶(α1,2-fucosyhransferase,α1,2-FT)基因转染对卵巢癌细胞RMG—I生物学特性的影响.利用PCR方法克隆人α1,2-FT基因的编码区HFUT—H,构建表达载体pcDNA3.1-HFUT—H.利用磷酸钙法将其转染入卵巢癌细胞系RMG—I,建立α1,2-FT基因稳定高表达细胞株RMG—I—H。采用RT—PCR及α1,2-FT活性测定检测转染前后细胞系α1,2-FT基因表达及α1,2-FT活性的变化,利用免疫细胞化学方法测定细胞表面Lewis y抗原表达变化,利用MTT法、流式细胞仪细胞增殖周期检测方法测定转染前后细胞系生物学特性的变化。分别以转染前细胞RMG—I和转染空载体细胞RMG—I-C为对照组。结果显示转染后细胞α1,2-FT mRNA表达增高,α1,2-FT活性增加20—30倍。转染后的细胞易复层生长,生长速度加快,细胞克隆边缘呈树突状延伸生长。转染后细胞RMG—I—H软琼脂克隆形成率(35%)明显高于对照组RMG—I(13%)及RMG—I—C(12%),为对照组的2.6倍。RMG—I—H细胞G1期比例从对照组的74.14%下降到59.46%,G2-M期和S期比例分别从对照组的2.05%和23.95%上升到7.32%和33.27%(P〈0.05)。这些结果充分说明。α1,2-FT及Lewisv抗原具有促进RMG—I细胞增殖,提高RMG—I细胞生存能力,促进肿瘤发生、发展的作用。 相似文献
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死亡结构域相关蛋白Daxx可以敏化多种肿瘤细胞的凋亡过程,但对于肝肿瘤细胞株HepG2的影响未见报道.为了研究Daxx增加肝HepG2细胞对药物敏感性的影响及机制,为开发药物新的药理作用提供理论依据,分别转染pEGFP-C1和pEGFP-C1-Daxx这两个载体到HepG2细胞.实验分组如下:(1)正常对照组(未转染细胞组);(2)pEGFP-C1空载体转染组(HepG2/GFP细胞);(3)pEGFP-C1-Daxx表达载体转染组(nepG2/GFP-Daxx细胞).筛选稳定细胞株,用逆转录聚合酶链反应检测mRNA的表达;用过氧化氢孵育24h诱导细胞凋亡,采用MTT法和流式细胞术检测细胞凋亡率,Western blot检测蛋白质的表达.经G418筛选稳定的细胞运用RT-PCR技术分析其mRNA,结果显示,转染绿色荧光蛋白Daxx表达载体的细胞Daxx的mRNA明显上调:用荧光显微镜观察到Daxx蛋白主要定位于细胞核.用过氧化氢诱导HepG2细胞凋亡,观察到过氧化氢呈浓度依赖性地抑制HepG2细胞活性.正常对照细胞、HepG2/GFP、HepG2/GFP-Daxx 3组细胞的IC50值分别是0.72、0.76、0.49mmol/L.并且运用流式细胞仪检测到HepG2/GFP-Daxx组细胞凋亡率明显高于转染空载体质粒组与未转染组((42.9±8.42)vs(27.3±6.38)or(28.5±4.71)).提示HepG2/GFP-Daxx细胞对过氧化氢的反应性较未转染细胞和HepG2/GFP敏感.还运用Western-blot检测到活化的caspase3在Daxx转染组细胞表达最强,达到(204.66±19.68)%,而未转染和HepG2/GFP组细胞分别是(100±3.1)%、(107.39±20.1)%,进一步说明了Daxx可以增加HepG2细胞对于过氧化氢的敏感性.同时,观察到过氧化氢处理24h后,Daxx转染组细胞磷酸化的JNK表达明显高于空载体转染组和未转染细胞组.上述结果表明:a.Daxx可以增加肝HepG2细胞对过氧化氢诱导的细胞凋亡敏感性;b.Daxx蛋白敏化过氧化氢诱导的HepG2细胞凋亡可能与协同增加JNK活性有关. 相似文献
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以α1,2-岩藻糖转移酶基因转染前后卵巢癌细胞RMG-I、RMG-I-H为细胞模型,用细胞免疫荧光方法检测转染前后细胞p38MAPK和p-p38MAPK的细胞内定位,RT-PCR和Western blot方法从mRNA和蛋白质两个水平检测转染前后细胞p38MAPK表达的变化;以兔抗人IgG抗体处理组为对照,分别利用RT-PCR和Western blot方法检测Lewisy单克隆抗体处理前后RMG-I-H细胞p38MAPK mRNA和蛋白质表达水平的变化;以0.1%DMSO为对照,用流式细胞仪(FCM)检测p38MAPK特异性抑制剂SB203580处理后RMG-I-H凋亡比率的变化,并利用RT-PCR和Western blot方法检测caspase-3的mRNA和蛋白质水平的变化;用RT-PCR方法检测卡铂和SB203580处理后p38MAPK及caspase-3表达的变化.结果表明,RMG-I与RMG-I-H的p38MAPK蛋白主要定位在细胞质,p-p38MAPK蛋白定位在细胞核,转染后p38MAPK的mRNA水平明显高于转染前(P<0.05);Lewisy单克隆抗体处理后RMG-I-H细胞p38MAPK m... 相似文献
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目的:探讨喉鳞癌患者血清中内皮抑素水平的变化,及其与肿瘤临床分期及预后的关系。方法:(1)对50例喉鳞癌患者、30例喉息肉患者和30例健康人用ELISA方法检测血清中内皮抑素水平;(2)对喉鳞癌组不同临床分期的血清中内皮抑素的水平进行比较。结果:(1)喉鳞癌组血清中内皮抑素水平(51.45±19.83ng/mL),显著高于喉息肉组(34.56±12.4ng/mL)和正常对照组(33.12±13.04ng/mL),差别有统计学意义(P〈0.01)。喉息肉组与正常对照组之间差别无显著性(P〉0.05)。(2)Ⅱ期喉鳞癌患者血清内皮抑素的水平(66.22±10.89ng/mL)高于Ⅰ、Ⅱ期患者内皮抑素水平(39.31±14.42ng/mL,47.98±22.01ng/mL),差别有统计学意义(P〈0.01),Ⅰ期与Ⅱ期之间内皮抑素水平差别无显著性(P〉0.05)。结论:内皮抑素含量水平可以作为喉鳞癌的诊断及顸后判断的重要指标之一。 相似文献
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目的:研究Survivin特异性SiRNA(small interfering RNA)对鼻咽癌移植瘤的放疗增敏作用,探索提高鼻咽癌疗效的新方法。方法:Survivin特异性SiRNA转染鼻咽癌5-8F细胞系,培养48h后,采用RT-PCR、流式细胞仪(flow cytometry,FCM)分别检测Survivin mRNA和蛋白在5-8F细胞中表达。将Survivin基因特异性SiRNA转染5-8F细胞,培养24h后,用剂量为6GY的放射线处理,培养6h后,收集细胞,进行裸鼠皮下接种,50d后处死裸鼠,对移植瘤进行分析。结果:Survivin特异性SiRNA能有效抑制5-8F细胞中Survivin表达。Survivin特异性SiRNA组,Survivin表达阳性率12.37±1.86%,与对照组阳性率91.93±1.3%和阴性对照组阳性率92.43±2.34%比较,差别具有显著性(p〈0.01)。特异性SiRNA加放射组移植瘤(0.03±0.03g)显著小于特异性SiRNA组(0.28±0.02g,p〈0.01)与阴性SiRNA加放射组(0.17±0.02g,p〈0.01)。结论:Survivin特异性SiRNA增强了鼻咽癌5-8F细胞移植瘤的放射敏感性。 相似文献
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目的:观察三氧化二砷(As2O3)脂质体通过载瘤大鼠血脑屏障(BBB)的效果。方法:超声薄膜分散法制备三氧化二砷脂质体,建立药物标准曲线,检测包封率;立体定向技术建立C6/Wistar大鼠脑胶质瘤模型;取Wistar雄性载瘤大鼠84只,随机分为三氧化二砷脂质体组和三氧化二砷组,分别经静脉注射三氧化二砷脂质体和三氧化二砷注射液,给药后0.5h、1h、2h、4h、8h、16h、24h取大鼠脑组织冻存,应用双道原子荧光法检测载瘤大鼠脑组织中的砷含量。结果:制备稳定的三氧化二砷脂质体,包封率分别为92、2%,92.2%,92.3%;As2O3脂质体组及As2O3给药后7个时间点鼠脑组织中砷含量(μg/L)分别为:341.09±18.18,523、98±27.36,475.19±15、52,467.02±22.46,471.52±24.38,382.30±13.26,282.47±19.71;99.93±17.10,148.07±26、21,101.78±17.54,89.09±19.41,74.39±13.85,50.44±15.31,51.52±19.23。比较给三氧化二砷组及给三氧化二砷脂质体组载瘤大鼠脑组织中砷含量有显著差异(P〈0.05)。结论:三氧化二砷脂质体对血脑屏障的透过性明显优于单纯砷剂。 相似文献
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人工养殖云斑尖塘鳢的生长特性 总被引:2,自引:1,他引:1
研究了人工养殖条件下云斑尖塘鳢(Oxyeleotris marmoratus)的生长特性。结果表明:经过2个月的生长期,云斑尖塘鳢的平均体长从最初的(17.36±0.99)cm增加到(19.05±0.57)cm,体质量从(139.13±12.90)g增加到(205.50±15.78)g,体长增加10%,体质量增加48%。不同的养殖时间除对摄食率(FR)无显著影响外(P〉0.05),对特定生长率(SGR)、饵料转化效率(FCR)和生长效率(GE)都有显著影响(P〈0.05)。体长生长与时间表现为线性相关,体质量生长与时间表现为指数相关。云斑尖塘鳢体质量与体长之间呈幂函数关系,不同养殖时间下,幂指数b值都接近3,表明云斑尖塘鳢的体长和体质量呈等速生长。 相似文献
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目的探讨Ad—GFP—nm23-H1对人恶性黑素瘤裸鼠皮下移植瘤的抑制作用,从而为后期nm23-H1基因和腺病毒载体用于人恶性黑色素瘤及其它肿瘤的基因治疗提供一定的理论和方法。方法在裸鼠真皮下建立人A375细胞黑色素瘤动物模型后,设对照组及10^9 PFU/ml、10^10 PFU/ml的Ad—GFP—nm23-H1干预组。经Ad—GFP—nm23-H1干预治疗后,取瘤体称重,计算抑瘤率,通过光镜进行瘤组织病理形态学观察。结果对照组及10^9 PFU/ml、10^10 PFU/ml的Ad—GFP-nm23-H1干预组的平均肿瘤体积和瘤重分别为:1.4129±0.4832mm^3、1.1914±0.3304mm^3、0.75±0.2548mm^3和1.924±0.539g、1.655±0.5754g、1.195±0.2639g。与另两组比较,10^10 PFU/ml的Ad.GFP—nm23-H1干预组对A375具有明显的抑制作用。结论10^10 PFU/ml的Ad—GFP—nm23-H1干预组对裸鼠移植A375实体瘤有明显的抑制作用。 相似文献
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目的探讨氨溴索对铜绿假单胞菌临床分离株形成的生物膜(biofilm,BF)主要成分藻酸盐的干预作用,研究其对藻酸盐合成过程中起重要作用的基因表达和合成过程中限速酶活性的影响,以及其对藻酸盐降解的影响。方法建立铜绿似单胞菌临床分离株BF体外模型,培养7d后得到成熟BF。将BF内的细菌振荡下来后,用疏酸-苯酚法检测氨溴索对藻酸盐含量的影响;RT-PCR检测藻酸盐合成过程中重要基因algD、algU、algR和mucA的mRNA表达;分光光度计检测合成过程中限速酶——GDP-甘露糖脱氢酶(guanosine diphospho-D-mannose dehydrogenase,GMD)的活性,并检测藻酸盐的降解情况。结果在氨溴索3.75mg/ml作用下,藻酸盐含量(mg/g)由86.4024±0.8588下降到59.9199±0.5803(F=66.2,P〈0.01);其合成重要基因algD、algU、algR和mucA的mRNA的表达分别由1.2994±0.0173、1.0488±0.0457、0.9888±0.0267和0.8731±0.0336变化为1.0253±0.0265、0.9594±0.0106、0.8536±0.0179和1.0770±0.0503(F=91.9,41.1,88.4和56,9,P均〈0.05);其合成限速酶GMD活性由0.0989±0.0055下降到0.0558±0.0016(F=121.2,P〈0.01);藻酸盐的降解量(△mg/g)由1.4122±0.0073变化为1.4175±0.0019(F=21.81,P〉0.05)。1.875mg/ml氨溴索作用下,有同样的趋势但效应不如高浓度明显。结论氨溴索可以降低铜绿假单胞菌BF藻酸盐的含量,影响藻酸盐合成过程中重要基因algD、algU、algR和mucA的mRNA的表达,降低藻酸盐合成限速酶GMD活性,但对藻酸盐的降解无影响。 相似文献
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冷冻对山羊精子转染外源DNA和体外制备转基因胚胎的影响 总被引:2,自引:0,他引:2
本实验将鲜精和冻精分别与地高锌标记的线形化的pEGFP-N,质粒孵育转染,用原位杂交方法检测转染效率;PCR和Southern Blotting检测精子与外源DNA的整合效率;与成熟卵母细胞体外受精,PCR检测阳性胚胎比率,用透射电镜技术、碘化丙锭和羟化荧光素双探针技术和单细胞电泳(Single Cell Gel Electrophoresis,SCGE)技术,观察精子冷冻前后的超微结构、精子质膜完整性和精子核DNA损伤的变化,研究冷冻对山羊(Caprahircus)精子转染内化外源DNA和体外制备转基因胚胎的影响及机理。结果表明,冻精显著提高了转染外源DNA的效率(81.60%±16.59%VS32.95%±2.93%,t=4.873,P=0.003;41.80%±6.26%vs27.89%±8.64%,t=2.634,P=0.039)。PCR和Southern Blotting检测表明外源DNA已经整合到精子基因组上。用冻精与成熟卵母细胞体外受精,体外受精穿透率和卵裂率显著低于鲜精组(24.19%±3.15%vs58.86%±3.73%,t=7.131,P〈0.001;11.83%±2.37%vs29.71±3.47%,t=4.302,P〈0.001),但体外生产的胚胎PCR阳性率比鲜精组显著提高(45.45%±10.87%VS24.44%±6.06%,t=1.750,P=0.013)。超微结构观察和双荧光探针检测都发现冷冻-解冻精子质膜完整性降低(8.34%±4.21%VS65.67%±6.46%,t=12.492,P〈0.001),SCGE显示冷冻极显著增加了精子彗尾长度和彗星细胞比例(42.67μm±4.56μmvs21.14/Lm±2.36μm,t=5.644,P=0.005;60.00%±4.00%vs17.37%±2.57%;t=15.787,P〈0.001)。冷冻-解冻可以提高山羊精子转染外源DNA的效率,冷冻破坏精子质膜完整性,解除质膜的阻碍作用,是提高外源DNA转染效率的一个主要原因[动物学报54(6):1089-1097,2008]。 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