沉默UVRAG基因在二烯丙基二硫诱导K562细胞中caspase3的表达

目的:沉默UVRAG基因在DADS诱导K562细胞中观察caspase3的表达。方法:以K562细胞为细胞模型,将构建成功并筛选出最有效干扰抑制UVRAG基因的si RNA序列片段采用lipofectamine TM2000脂质体转染法转染白血病K562细胞,组别为:空白对照组,转染试剂组、阴性对照组,阳性对照组,转染24小时后,利用QT-PCR检测UVRAG m RNA的表达水平以此观察干扰效果,再以40 mg/LDADS处理转染试剂组12小时,采用蛋白印迹(Western Blotting)技术检测凋亡相关基因caspase3的表达。结果:QT-PCR显示:与空白组相比,UVRAG m RNA表达明显减少,表明沉默UVRAG基因成功;Western Blotting显示:DADS处理的干扰成功的K562细胞12小时后,检测到caspase3的蛋白表达水平下降。结论:沉默UVRAG基因能使白血病K562细胞中凋亡相关基因caspase3的蛋白表达水平下降,提示抑制UVRAG表达的同时也可能抑制DADS诱导K562细胞的凋亡。     

RNA干扰c-maf基因表达对多发性骨髓瘤细胞凋亡的影响及机制研究

目的:探讨RNA干扰c-maf基因表达对多发性骨髓瘤细胞凋亡的影响及机制。方法:将人骨髓瘤细胞株NCI-H929分为正常对照组、转染si RNA Control的阴性对照组和转染si RNA c-maf基因的沉默组,转染48 h后,提取细胞中的蛋白,Western blot检测各组细胞中c-maf的蛋白表达,流式细胞仪检测细胞凋亡情况,Western blot检测凋亡相关蛋白Cleaved caspase3及Wnt/β-catenin信号通路相关蛋白β-catenin和Cyclin D1蛋白表达。结果:阴性对照组c-maf的蛋白表达与正常对照组比较差异无统计学意义(P0.05),沉默组c-maf的蛋白表达显著低于正常对照组(P0.01),而阴性对照组c-maf的蛋白表达与正常对照组比较差异无统计学意义(P0.05)。与阴性对照组比较,沉默组的细胞凋亡率显著升高,Cleaved caspase3蛋白显著上调表达,β-catenin和Cyclin D1蛋白显著下调表达(P0.01)。结论:RNA干扰c-maf基因表达可诱导多发性骨髓瘤细胞凋亡,其机制可能与抑制Wnt/β-catenin信号通路有关。     

RNAi靶向抑制p65基因对大鼠骨髓间充质干细胞向神经元分化的影响

目的:探讨RNAi靶向抑制p65基因对骨髓间充质干细胞(MSCs)向神经元分化中的影响。方法:采用RNAi干扰技术,Rn-p65-siRNA转染体外培养的大鼠MSCs,用盐酸法舒地尔诱导MSCs向神经元分化,并以未转染组及Cy3标记的negative control siRNA为对照组。在倒置荧光显微镜下观察经negative control siRNA转染24 h、48h及72 h后MSCs的荧光表达变化;采用MTT比色法检测转染前、转染24 h、48 h及72 h后MSCs的存活率;RTPCR检测p65 mRNA的表达;Western blot法检测3组MSCs中p65蛋白的表达;细胞免疫组化法检测p65蛋白、神经元特异性烯醇化酶(NSE)、神经元微管结合蛋白(MAP-2)和胶质细胞原纤维酸性蛋白(GFAP)的表达。结果:Negative control siRNA转染72 h,MSCs荧光表达最强,转染率可达83.3%±3.8%;Rn-p65-siRNA转染组MSCs的p65 mRNA转录下降,p65蛋白表达减少;Rn-p65-siRNA转染组的MSCs存活率也显著减少,显著高于对照组(P0.05)。转染72 h后,诱导转染组MSCs向神经元分化的诱导效果最佳,可高效表达NSE、MAP-2等,而不表达胶质纤维酸性蛋白(GFAP),与对照组比较有统计学差异(P0.05)。结论:靶向抑制p65基因表达可促进骨髓间充质干细胞(MSCs)向神经元分化。     

PARP-1对高糖诱导的心肌细胞增殖的影响及机制研究

目的:研究PARP-1对高糖诱导的心肌细胞增殖的影响及可能机制。方法:用高糖处理H9C2细胞,qRT-PCR和Western blot检测细胞中PARP-1 m RNA和蛋白水平。H9C2细胞转染PARP-1 si RNA和si RNA control,q RT-PCR和Western blot检测细胞中PARP-1 m RNA和蛋白水平。用高糖处理转染PARP-1 si RNA后的H9C2细胞,CCK-8检测细胞增殖情况,硫代巴比妥酸法检测丙二醛(MDA)水平,黄嘌呤氧化酶法检测超氧化物歧化酶(SOD)水平,Western blot检测增殖细胞核抗原(PCNA)、p38丝裂原活化蛋白激酶(p38MAPK)、磷酸化的p38MAPK(p-p38MAPK)蛋白的表达。结果:高糖诱导的H9C2细胞中PARP-1 m RNA和蛋白水平明显高于正常培养的H9C2细胞(P0.05)。PARP-1 si RNA能够明显下调H9C2细胞中PARP-1 m RNA和蛋白水平。高糖处理后H9C2细胞存活率明显降低,细胞中MDA水平升高,细胞中SOD水平降低,细胞内的PCNA水平降低,p38MAPK磷酸化水平升高,与正常培养的H9C2细胞相比,差异均具有统计学意义(P0.05)。用高糖培养下调PARP-1的H9C2细胞,细胞存活率有所升高,细胞中MDA水平降低,细胞中SOD水平也升高,细胞中PCNA水平升高,细胞中p38MAPK磷酸化水平降低,与单纯高糖培养的细胞相比,差异均具有统计学意义(P0.05)。结论:PARP-1在高糖诱导的心肌细胞中表达上调,可能通过激活p38MAPK信号途径,增加细胞脂质氧化应激抑制心肌细胞增殖。     

Mcl-1 调控NSCLC 对EGFR-TKIs敏感性的实验研究

目的:探讨人髓细胞白血病基因-1(myeloid cell leukemia-1,Mcl-1)是否参与调控非小细胞肺癌(non-small cell lung cancer,NSCLC)对EGFR-TKIs的敏感性,为非小细胞肺癌的治疗提供新的思路。方法:通过Western blot方法检测EGFR-TKIs敏感细胞H3255和耐药细胞H1975中Mcl-1蛋白的表达水平。分别给予敏感细胞H3255和耐药细胞H1975 EGFR-TKIs处理后检测细胞凋亡情况和Mcl-1蛋白表达水平。设计并合成特异性si RNA下调耐药细胞H1975中Mcl-1的表达,采用脂质体转染后通过流式细胞技术检测细胞的凋亡情况。结果:H3255细胞Mcl-1表达水平明显低于H1975细胞。一代EGFR-TKIs Gefitinib显著降低H3255细胞Mcl-1表达而不能减少H1975细胞Mcl-1表达。H1975细胞经二代EGFR-TKIs Afatinib和三代EGFR-TKIs AZD9291处理后Mcl-1表达明显减少。特异性si RNA下调H1975细胞Mcl-1表达可以促进细胞凋亡。结论:Mcl-1参与了调节NSCLC对EGFR-TKIs的敏感性,可能成为防止或逆转NSCLC对EGFR-TKIs耐药的潜在靶点。     

卵巢癌组织中UHRF1蛋白的表达及其与卵巢癌细胞增殖和侵袭的关系

目的:研究卵巢癌组织中泛素样含PHD和环指域1(Ubiquitin-like with PHD and ring finger domains 1,UHRF1)蛋白的表达及UHRF1对卵巢癌细胞增殖、侵袭的影响。方法:选取卵巢癌组织和癌旁正常组织,采用蛋白印迹法(Western blot)检测其UHRF1的蛋白表达。体外培养卵巢癌SKOV-3细胞株,分别转染UHRF1的si RNA和阴性对照si RNA,采用CCK-8检测细胞活力,Transwell检测细胞侵袭能力,荧光定量聚合酶链式反应法(FQ-PCR)检测Cyclin D1、CDK6、MMP2和MMP9的m RNA表达。结果:卵巢癌组织中UHRF1蛋白表达水平显著高于癌旁正常组织(P0.05);与转染阴性对照si RNA的SKOV-3细胞相比,转染UHRF1的si RNA的SKOV-3细胞活力明显降低、侵袭细胞数目明显减少(P0.05),且细胞中Cyclin D1、CDK6、MMP2和MMP9基因的m RNA表达水平显著降低(P0.05)。结论:UHRF1蛋白在卵巢癌组织中呈高表达状态,且可促进卵巢癌细胞的增殖和侵袭。     

CircRNA-0028171调控三氧化二砷诱导的血管内皮细胞凋亡

本文旨在研究circ RNA-0028171对三氧化二砷(As₂O₃)诱导的血管内皮细胞凋亡的调控作用。用0～15μmol/L As₂O₃作用人脐静脉血管内皮细胞(human umbilical vein endothelial cells,HUVECs) 24 h,用MTT法检测HUVECs损伤情况,用实时定量PCR检测circ RNA-0028171及凋亡相关蛋白Bcl-2、Bax m RNA表达水平,用Western blot检测Bcl-2、Bax蛋白表达水平。通过转染circ RNA-0028171过表达质粒和si RNA观察circ RNA-0028171是否参与As₂O₃对HUVECs的调控。结果显示,与对照组相比,As₂O₃组细胞活性显著下降,Bcl-2/Bax m RNA比值和蛋白比值显著降低,circ RNA-0028171显著低表达。过表达circ RNA-0028171抑制As_2<...     

HIF-1α/MMP9信号通路介导低氧诱导的人视网膜母细胞瘤HXO-RB44细胞侵袭

目的:探究低氧条件下人视网膜母细胞瘤细胞侵袭能力的变化及其调控机制。方法:将人视网膜母细胞瘤HXO-RB44细胞株于常氧(21%O_2)和低氧(1%O_2)条件下培养,采用Transwell侵袭实验检测细胞侵袭能力,real time-PCR和Western blot法检测细胞中HIF-1α及MMP9 m RNA和蛋白的表达水平,荧光素酶报告基因分别检测低氧对HIF-1α、HIF-1α对MMP9启动子区域的调控作用。并进一步使用HIF-1α及MMP9特异性si RNA阻断其表达,并检测低氧对细胞侵袭能力的影响。结果:低氧组Transwell下室HXO-RB44每高倍视野细胞数目、HXO-RB44HIF-1α和MMP9 m RNA和蛋白表达均较常氧组显著上调(P0.05)。转染HIF-1α过表达质粒组的MMP9活性较空载组相比明显增加(P0.05),低氧处理24小时的HXO-RB44细胞的HIF-1α启动子活性较常氧组明显增强(P0.05)。HIF-1αsi RNA组的HIF-1α及MMP9的m RNA和蛋白表达水平较NC组明显降低(P0.05),MMP9 si RNA组的HIF-1αm RNA和蛋白无明显改变,分别转染HIF-1αsi RNA组MMP9 si RNA组下室HXO-RB44每高倍视野细胞数目显著减少(P0.05)。结论:低氧能够促进HXO-RB44细胞株的侵袭转移,而可HIF-1α/MMP9轴在这一过程起关键作用。     

PACE4对异丙肾上腺素诱导的心肌细胞凋亡的影响及其机制

目的:研究前体蛋白转化酶枯草溶菌素(PACE4)对异丙肾上腺素(ISO)诱导的心肌细胞凋亡的作用及其可能的作用机制。方法:构建pFLAG-PACE4重组表达载体并转染H9c2心肌细胞。将心肌细胞分为四组:正常对照组(无任何干预因素)、ISO组(10μmol/L ISO)、ISO+pFLAG组(空载质粒pFLAG转染+10μmol/LISO)、ISO+pFLAG-PACE4组(pFLAG-PACE4重组表达质粒转染+10μmol/LISO)。采用AnnexinV-FITC/PI双染法测定心肌细胞凋亡率;蛋白免疫印迹法检测活性半胱氨酸蛋白酶(caspase)-3、caspase-12、钙网蛋白、葡萄糖调节蛋白78(GRP78)、CCAAT/增强子结合蛋白同源蛋白(CHOP)、活化转录因子4(ATF4)和PERK的表达以及真核起始因子2α(eIF2α)的磷酸化水平。结果:与正常对照组相比,ISO组中PACE4表达水平明显降低,而转染pFLAG-PACE4质粒后,其表达水平显著增加。PACE4过表达可以显著抑制ISO诱导的细胞凋亡和caspase-3以及caspase-12的蛋白表达。ISO处理显著增加内质网应激分子钙网蛋白、GRP78和CHOP的表达,而PACE4过表达则可以抑制这些蛋白的表达。ISO诱导的PERK、eIF2α和ATF4的表达可以显著被PACE4过表达抑制。结论:PACE4过表达可以抑制ISO诱导的H9c2心肌细胞凋亡,其机制可能与PERK信号通路介导的内质网应激反应有关。     

lncRNA BANCR 在晶体上皮细胞上皮-间质转化，增殖、凋亡及自噬的作用

目的:探索长链非编码RNA BANCR(lncRNA BANCR)在人晶状体上皮细胞FHL24中对上皮-间质转化的作用,并进一步探究了其调控晶体上皮细胞增殖、凋亡及自噬的作用及相关分子机制。方法:运用qReal-time PCR检测TGF-β诱导对FHL24细胞内EMT相关标志物α-SMA,E-cadherin,Coll I,ZO1及BANCR m RNA相对表达量。细胞中转染BANCR。Western印迹检测各组细胞中EMT相关标志蛋白及LC3Ⅱ/Ⅰ的蛋白表达。MTT法检测各组细胞的增殖,凋亡情况。结果:与正常对照组比较,TGF-β诱导组细胞中BANCR,α-SMA, Coll I,ZO1 m RNA的相对表达量明显增加,而E-cadherin m RNA显著下降,差异均有统计学意义(t=-5.031,-7.145,-9.023,-6.012, 5.097均P0.05),以上因子的蛋白表达趋势相同,差异均有统计学意义(均P0.05)。si RNA-BANCR TGF-β诱导组细胞中E-cadherin m RNA相对表达量比si RNA TGF-β诱导组显著增加(t=-9.98, P0.05);α-SMA,Coll I及ZO1 m RNA相对表则显著减少(t=9.003; 27.738; 19.620, P0.05)。抑制BANCR后细胞增殖活力48、72 h时细胞活性显著降低(t=5.032, 9.041,均P0.05),细胞凋亡率显著升(t=16.772,P0.001)。自噬标志蛋白LC3-II/LC3-I比例增加(P 0.05)。结论:长链非编码BANCR参与了晶体上皮细胞的抑制其上皮-间质转化,抑制BANCR可抑制晶体上皮细胞增殖、增加凋亡及自噬的发生。     

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.