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1.
目的 构建可表达丙型肝炎病毒 (HCV)NS5B EGFP融合蛋白的真核表达载体 ;获得重组质粒稳定转染的HepG2 细胞系。方法 利用PCR技术从HCV基因组中扩增出ns5b基因片段 ,XhoⅠ KpnⅠ双酶切后连接到经同样酶切的pEGFP N3真核表达载体 ,转化TG1菌株感受态细胞 ,获得阳性重组质粒pEGFPN3 ns5b。将阳性克隆用脂质体法转染HepG2 细胞 ,经持续G4 18压力选择和有限稀释法克隆化获得稳定转染的细胞系。结果 成功构建了真核表达载体pEGFPN3 ns5b ;建立了其重组质粒稳定转染的HepG2 细胞系。结论 重组质粒稳定转染的HepG2 细胞系可表达NS5B EGFP融合蛋白 ;该HepG2 细胞系可以应用于以ns5b基因为靶位的抗HCV感染研究  相似文献   

2.
 摘要:目的 分析HCV核心蛋白(HCV-Core)对HepG2细胞microRNA表达谱的影响。方法 将构建好的重组真核表达质粒pCDNA3.1(+)/HCV-Core用脂质体转染HepG2细胞,经G418筛选得到稳定转染HCV-Core的HepG2细胞,命名为HepG2-HCV Core细胞株。然后用反转录聚合酶链反应(RT-PCR),细胞免疫荧光和Western blot对HCV核心蛋白在HepG2细胞里mRNA和蛋白水平的表达情况进行验证。利用博奥生物公司的miRNA Array基因芯片,分析稳定表达HCV核心蛋白的HepG2细胞和转染空质粒pCDNA3.1(+)的HepG2细胞二者microRNA表达谱的差异,最后用Taqman探针荧光定量PCR法进行验证。 结果 感染HCV-Core后,HepG2细胞表达有差异的microRNA有8种,用Taqman探针荧光定量PCR法进行分析,发现HCV核心蛋白可以上调miR-29、 miR-146a、miR-149、miR-192、miR-221、miR-222和miR-193b;下调miR-196a。结论 HCV核心蛋白可以诱导肝细胞microRNA表达谱发生改变,在肝癌发生发展过程中发挥重要作用。  相似文献   

3.
HCV核心蛋白与HBV X蛋白协同反式激活作用的研究   总被引:12,自引:3,他引:12  
目的:探讨HCV核心蛋白与HBV X蛋白的协同反式激活作用。方法:构建表达HCV核心蛋白的重组质粒pcDNA3.1(-)core和表达HBV X蛋白的重组质粒pcDNA3.1(-)X;转染HepG2细胞,从转录和翻译水平鉴定病毒基因的瞬时表达;与报告质粒pSV-lacZ共转染HepG2细胞,检测β-半乳糖苷酶表达活性,酶的活性反映了表达的肝炎病毒蛋白对SV40病毒早期启动子/增强子功能的影响。结果:构建成HCV核心蛋白及HBV X蛋白的重组表达载体pcDNA3.1(-)core、pcDNA3.1(-)X;在HepG2细胞均能瞬时表达相应的肝炎病毒蛋白;单独共转染试验中pcDNA3.1(-)core、pcDNA3.1(-)X组的β-半乳糖苷酶的表达分别是对照的4.9、3.5倍,两种质粒共同转染时酶的表达是对照的9倍;表达质粒对β-半乳糖苷酶表达的激活作用呈剂量依赖性。结论:HepG2细胞中表达的HCV核心蛋白和HBV X蛋白均具有反式激活SV40早期启动子/增强子的功能,并且两种蛋白的反式激活功能具有协同特性。本试验有助于解释HCV、HBV感染,尤其是共同感染的致病/癌机制。  相似文献   

4.
目的研究丙型肝炎病毒(HCV)核心蛋白是否影响环氧化酶-2(COX-2)的表达。方法用PCR从含HCVH77株全长基因组序列质粒中扩增HCV核心蛋白基因,并克隆至pcDNA3.1载体中,构建HCV核心蛋白基因的真核表达载体HCV-C/pcDNA3.1。用HCV-C/pcDNA3.1和含COX-2启动子的荧光素酶报告载体COX2pro1.5kb/luc瞬时共转染HepG2细胞,测定萤火虫荧光素酶的活性,并用Westernblot检测COX-2蛋白的表达水平。结果成功地构建了HCV-C/pcD-NA3.1重组质粒。瞬时转染后的HepG2细胞中,COX2启动子荧光素酶的活性显著增强。Westernblot检测,发现COX-2的表达明显升高。结论HCV核心蛋白在HepG2细胞中激活COX-2启动子,并且明显诱导COX-2的表达,为进一步研究COX-2与HCV致病性的关系提供了新的实验依据。  相似文献   

5.
丙型肝炎双移位F蛋白抑制肝癌细胞p16、p21的表达   总被引:1,自引:0,他引:1  
目的:探讨丙型肝炎双移位F(DF)蛋白对肝癌细胞抑癌基因p16、p21转录与表达的影响。方法:PCR扩增HCV1b型DF基因,构建pCDNA3.0/HCV-DF真核表达载体。再转染至肝癌细胞HepG2中,G418筛选稳定表达细胞株,Western blot检测p16、p21蛋白表达及半定量RT-PCR法检测p16、p21基因转录,并以pCDNA3.0空质粒作为阴性对照。结果:重组质粒pCDNA3.0/HCV-DF蛋白在HepG2细胞中稳定表达,pCDNA3.0/HCV-DF转染细胞中p16、p21 mR-NA转录水平和蛋白表达水平较空质粒转染的细胞明显下降。结论:HCV-DF蛋白能够抑制p16、p21表达,提示可能参与肝细胞癌变发生发展。  相似文献   

6.
目的构建绿色荧光蛋白(GFP)与人乙型肝炎病毒(HBV)X基因的重组表达载体,建立稳定表达HBVX蛋白(HBx)与GFP融合蛋白的HepG2细胞系,以进一步研究HBx的生物学功能及其在肝癌发生中的作用。方法应用PCR法从adr亚型HBV质粒pHBVDNA中扩增HBVX基因片段,PCR产物经HindⅢ和KpnⅠ双酶切后定向插入绿色荧光蛋白真核表达载体pEGFP-C1的相应酶切位点,转化宿主菌DH5α,采用上述双酶切及DNA测序鉴定重组质粒pGFP-HBx;采用脂质体转染法将pEGFP-C1质粒、pGFP-HBx重组质粒DNA转染人肝母细胞瘤细胞系HepG2细胞,G418选择抗性细胞克隆,荧光显微镜下观察GFP表达,挑取表达GFP的抗性克隆扩大培养、传代。采用RT-PCR检测转染细胞HBVX基因的表达。结果经酶切及测序鉴定成功构建了GFP-HBVX重组表达载体pGFP-HBx;将pEGFP-C1、pGFP-HBx重组质粒转染HepG2.,经G418筛选15d获得抗性细胞克隆。将带绿色荧光的抗性克隆细胞扩大培养并经传代70次,细胞仍表达强的荧光蛋白。RT-PCR检测表明转染pGFP-HBx重组体的HepG2/GFP-HBx细胞有HBVX转录、表达。结论成功构建了GFP.HBVX真核重组表达载体pGrP-HBx;获得了稳定表达GFP-HBx融合蛋白的HepG2细胞系,这为进一步研究FIBx的生物学功能以及HBx在肝癌发生中的作用与机制打下了基础。  相似文献   

7.
目的研究丙型肝炎病毒(HCV)F蛋白对细胞p21基因转录、表达的影响。方法PCR扩增HCV1b来源的F基因,克隆至pcDNA3.1真核表达载体。F基因质粒转染HepG2细胞,48h后抽提细胞总RNA和总蛋白,实时定量PCR及Westem blot检测p21基因表达变化。结果HCVF蛋白在HepG2细胞内瞬时表达,相对于空载体对照(目标基因表达量为1),HCVF基因质粒转染细胞的p21转录水平为3.2,蛋白表达水平为1.4。结论HCVF蛋白增加p21转录和表达,其生物学效应值得进一步研究。  相似文献   

8.
目的:探讨HCV—NS5A对PI3K表达的影响。方法:应用PCR技术从含有HCV全长开放阅读框的质粒中获得NS5A全长基因片段,利用基因重组技术将其克隆至真核表达载体pcDNA3.0(-)中。通过酶切、PCR及测序鉴定,NS5A基因已正确插入到pcDNA3.0(-)中,再利用脂质体转染HepG2细胞。结果:经RT—PCR及Western blot检测,HCV的NS5A基因在HepG2细胞中获得表达,而且在表达重组NS5A的转染HepG2细胞中,检测到PI3K蛋白的表达。结论:NS5A可在体外激活PI3K及其信号通路。  相似文献   

9.
目的建立稳定、高效的HBx、羧基末端截短的中分子表面蛋白(MHBst)体外表达细胞株,以进一步研究HBx、MHBst蛋白在肝癌发生中的作用及其机理。方法设计特异性引物,采用PCR方法从adr亚型HBV质粒pHBV DNA中扩增HBx、羧基末端截短至155位氨基酸的中分子表面蛋白(MHBst155)编码基因,并定向插入绿色荧光蛋白(GFP)表达载体pEGFP-C1的BglⅡ、KpnⅠ和BglⅡ、BamHⅠ酶切位点,转化宿主菌DH5α,提取质粒,分别用上述内切酶酶切及DNA测序鉴定重组质粒。采用脂质体介导将空载体、重组质粒分别转染到人肝肿瘤细胞株HepG2中,G418筛选抗性细胞克隆,荧光显微镜下观察GFP表达,挑取表达GFP的抗性克隆扩大培养、传代。采用RT-PCR、蛋白印迹检测抗性细胞中HBx、MHBst155的mRNA及蛋白水平。结果经酶切及测序鉴定成功构建了pGFP-HBx、pGFP-MHBst155重组表达载体,将空载体及重组质粒转染HepG2,经G418筛选约20 d获得抗性细胞克隆。将带有绿色荧光的抗性克隆扩大培养并经传代40次,细胞仍表达强的绿色荧光。RT-PCR及蛋白印迹检测表明转染重组体的HepG2/GFP-HBx、HepG2/GFP-MHBst155细胞有相应的条带,而空载体、空白对照组未出现条带。结论成功构建了HBx、MHBst155真核重组表达载体pGFP-HBx、pGFP-MHBst155,获得了稳定表达融合蛋白GFP-HBx、GFP-MHBst155的HepG2细胞系,为进一步研究HBx及MHBst蛋白在肝癌发生中的作用及分子机制构建了良好的平台。  相似文献   

10.
目的建立能表达丙型肝炎病毒核心蛋白(HCV core)的人肝癌细胞SMMC-7721的稳定转染细胞株。方法构建含目的基因HCV core的重组质粒,转染HEK293T细胞,包装获得含ZsGreen和HCV core基因的慢病毒后,感染SMMC-7721人肝癌细胞,采用实时荧光定量PCR检测HCV core mRNA表达,采用免疫荧光细胞化学染色和Western blot法检测HCV core蛋白表达,筛选稳定表达HCV core的细胞株。结果质粒酶切和序列测定证实重组载体构建正确;慢病毒包装48 h后可见清晰ZsGreen表达,感染SMMC-7721细胞后筛选获得稳定转染的细胞株,实时荧光定量PCR检测到HCV core mRNA,免疫荧光细胞化学染色和Western blot法均检测出HCV core蛋白表达。结论成功构建了表达HCV core蛋白的SMMC-7721人肝癌细胞的稳定转染细胞株。  相似文献   

11.
Over 200 schizophrenic patients belonging to three major and interrelated pedigree complexes have been investigated over the past 30 years in a North Swedish geographically isolated population, presently numbering about 6,000. An intensive investigation of a number of biochemical correlates and genetic markers in a few selected families belonging to one of the major pedigrees has indicated new strategies for the current research program.
Schizophrenia, as defined operationally, is significantly associated with decreased activities of two enzymes (1) blood platelet monoamine oxidase, (2) plasma dopamine-β-hydroxylase, and (3) with the genetic marker Gc2 (group specific antigen). Both enzymes are subject to genetic variation. A positive score for linkage between schizophrenia and low plasma DBH activity has been calculated, but, so far, available data are insufficient for discrimination between linkage and partial contribution of genetically controlled low plasma DBH to the pathogenesis of the disease. Alternatively, both mechanisms could be involved.
As a model for continued research, schizophrenia is explained as based on a double dominant-recessive genotype (Aabb), representing a vulnerability which in about 50 % of cases develops into clinical schizophrenia. It is suggested that the dominant mutation (A) operates on or affects MAO activity, and that the recessive genotype (bb) is instrumental in low variates of DBH activity and very likely such variates within the normal range of physiological variation. Moreover, it is suggested that the combined effects of MAO- and DBH-reduced efficiency on the metabolism of e.g. dopamine could be an essential pathogenic mechanism for the schizophrenic illness which is segregating in this population.  相似文献   

12.
About 1900, modern food selection and processing caused widespread epidemics of the B vitamin deficiency diseases of beriberi and pellagra which, for genetic reasons, often expressed as different diseases ranging from bowel and heart disease to dermatoses and psychoses. But the B vitamins merely help convert essential fatty acids (EFA) into the prostaglandin (PG) tissue regulators and it now turns out that, through hydrogenation, milling and selection of w3-poor southern foods, we have also been systematically depleting, by as much as 90%, a newly discovered trace Nordic EFA (w3) of special importance to primates and sole precursor of the PG3(4) series, even as a concurrent fiber deficiency increases body demand for EFA. Since substrate EFA is processed by many B vitamin catalysts, an EFA deficiency will mimic a panhypovitaminosis B, i.e., a mixture of substrate beriberi and substrate pellagra resembling vitamin beriberi and pellagra but exhibiting as even more diverse endemic disease. This would consitute a second stage of the Modern Malnutrition and explain why some workers now hold the dominant diseases of modermized societies to be new, nutritionally based, pellagraform yet lipid-related and to range, once again, from heart disease to psychosis. It is an assumption that our dominant diseases are unrelated to each other or are merely revealed by our diagnostic acumen and therapeutic success; and that hydrogenating millions of tons of food oils annually, to destroy the rancidity producing w3-EFA, is safe for primates. Extensive beriberiform disease is reported here in 32 typical cases taken from medical practice which responds strikingly to linseed oil supplements (60% w3-EFA) in confirmation of identical results in Capuchins.  相似文献   

13.
Most bodily functions require the coordinated actions of complementary and supplementary paired muscle groups. Where this essential muscular cooperation is lacking, hollow organs may burst and others become literally screwed up, giving rise to many similar spastic diseases such as Torticollis, Twisted ovarian cyst, Torsion of the Testis, Volvulus of the intestines, Varicose Veins, Megacolon, Aortamegaly, Scoliosis, Erb's Palsy, Peyronie's Disease, Main-en-Griffe, Undescended Foot (Pes Cavus), Talipes, Strabismus. Spasm is “panenepidemic” and unclassified examples of Torsion Dystonia and Dyskinesia really are as common as debt and taxes.  相似文献   

14.
15.
Newton H 《Medical history》2011,55(2):153-182
Sick children were ubiquitous in early modern England, and yet they have received very little attention from historians. Taking the elusive perspective of the child, this article explores the physical, emotional, and spiritual experience of illness in England between approximately 1580 and 1720. What was it like being ill and suffering pain? How did the young respond emotionally to the anticipation of death? It is argued that children’s experiences were characterised by profound ambivalence: illness could be terrifying and distressing, but also a source of emotional and spiritual fulfilment and joy. This interpretation challenges the common assumption amongst medical historians that the experiences of early modern patients were utterly miserable. It also sheds light on children’s emotional feelings for their parents, a subject often overlooked in the historiography of childhood. The primary sources used in this article include diaries, autobiographies, letters, the biographies of pious children, printed possession cases, doctors’ casebooks, and theological treatises concerning the afterlife.  相似文献   

16.
Recent advancements in agricultural biotechnology have created a need for analytical techniques to determine introduced proteins in crops enhanced through modern biotechnology techniques. These proteins are expressed in plant tissues and may be present in food ingredients. Immunoassays are ideally suited for protein detection and may be used as both quantitative and threshold methods. Microplate ELISA and lateral flow devices are two of the most commonly used immunoassay formats for agricultural biotechnology applications. This paper provides general background information and a discussion of criteria for the validation and application of immunochemical methods to the analysis of proteins introduced into plants and food ingredients using biotechnology methods. It is the result of a collaborative effort of members of the Analytical Environmental Immunochemical Consortium. This collaborative effort represents the combined expertise of several organizations to reach consensus on establishing guidelines for the validation and use of immunoassays. Further, the paper offers developers and users a consistent approach to adopting the technology as well as aid in producing accurate and meaningful results.  相似文献   

17.
The preparation steps usually necessary for obtaining ultrathin frozen sections of biological material (chemical prefixation, enclosing, cryoprotective treatment, freezing, sectioning, and post-staining the sections for transmission electron microscopy) are submitted to a critical analysis. The application of cryo-ultramicrotomy, in particularly for cytochemical purposes, is reviewed. Fundamental considerations of chemical prefixation and poststaining are supported by examples from yeast cytology. Furthermore, the efficiency of the cryo-ultramicrotomy (electron optical resolution of ultrastructural details) is demonstrated on yeast cells and protoplasts.  相似文献   

18.
Zusammenfassung Eine Reihe pathologischer Zustände bedingen Magnesiummangel. Zustände mit Hypermagnesämie sind ebenfalls bekannt, doch wesentlich seltener. Für den Kardiologen beachtenswert ist, daß unter Therapie mit bestimmten Diuretica bei Herzinsuffizienz, bei Herzinfarkt, Kardiomyopathie, Digitalisintoxikation und bestimmten Herzrhythmusstörungen Hypomagnesämie beobachtet wurde. Leider kann in der klinischen Routine nur ein extracelluläres Magnesiumdefizit durch Serumbestimmungen gemessen werden; über Magnesiummangel einzelner Organe kann nichts ausgesagt werden. Hinweise für Magnesiummangel geben aber neben der Messung des Serumspiegels Anamnese, klinischer Befund, bestimmte EKG-Veränderungen wie auch evtl. Hypokalämie, ein Zustand, bei dem sich oft — besonders bei Aldosteronismus — parallele Veränderungen zeigten.Tierexperimente deuten darauf hin, daß infarktähnliche Läsionen unter Magnesiummangel entstehen, doch ob Herzinfarkt beim Menschen durch Magnesiummangel ausgelöst werden kann, ist noch ungeklärt. In Leichenherzen zeigte sich im Infarktgebiet neben Calciumakkumulation signifikanter Magnesiumverlust, wobei unklar blieb, ob sich Ursache oder Folge des Infarktes widerspiegelten. Falls ein ursächlicher Zusammenhang besteht, ist er im Myokardstoffwechsel selbst zu suchen, wie bei der Alkoholkardiomyopathie, wo myokardialer Magnesiummangel zumindest als pathogenetischer Teilfaktor anerkannt wird. Andererseits versucht man aber auch Beziehungen zwischen Atherosklerose, Blutgerinnung und Hypomagnesämie herzustellen, in der Meinung, daß Magnesiummangel auch über den coronaren Pathomechanismus des Herzinfarktes wirken könnte. Sicher scheint, daß gewisse EKG-Veränderungen und Herzrhythmusstörungen durch einen irritierten Magnesiumhaushalt bedingt sein können, da sie bei Gabe bzw. Entzug von Magnesium verschwinden. Daß Magnesiummangel die Glykosidtoleranz verringert, wird tierexperimentell bestätigt. Unter Hypomagnesämie bewirkt Acetylstrophanthidin eher und länger Rhythmusstörungen als ohne, außerdem lassen diese sich durch Magnesiumgaben eliminieren. Da in gewissen Fällen spontane und digitalisinduzierte Herzrythmusstörungen durch Magnesiuminjektionen beseitigt wurden, scheint Magnesium als Therapeuticum angebracht. Einsatz verschiedener Magnesiumsalze bei Angina pectoris, degenerativen Herzerkrankungen und Herzinsuffizienz ohne geprüften und offensichtlich gestörten Magnesiumhaushalt ist fragwürdig, weil keine eindeutigen klinischen Erfolgsbeweise vorliegen. Immerhin mag es aber larvierte, durch Serumbestimmungen nicht erfaßbare Mangelzustände geben. Allgemein erscheint es aus kardiologischer Sicht ratsam, den Magnesiumhaushalt zu überwachen und in entsprechenden Fällen auszugleichen, um möglichen Myokardläsionen oder fatalen Herzrhythmusstörungen entgegenzuwirken.  相似文献   

19.
HLA-A,-B,-C,-DRB1 and -DQB1 alleles have been studied in Chimila Amerindians from Sabana de San Angel (North Colombian Coast) by using high resolution molecular typing. A frequent extended haplotype was found:HLA-A*24:02-B*51:10-C*15:02-BRB1*04:07-DQB1*03:02 (28.7%) which has also been described in Amerinndian Mayos Mexican population (Mexico, California Gulf, Pacific Ocean). Other haplotypes had already been found in Amerindians from Mexico (Pacific and Atlantic Coast), Peru (highlands and Amazon Basin), Bolivia and North USA. A geographic pattern according to HLA allele or haplotype frequencies is lacking in Amerindians, as already known. Also, five new extended haplotypes were found in Chimila Amerindians. Their HLA-A*24:02 high frequencies characteristic is shared with aboriginal populations of Taiwan; also, HLA-C*01:02 high frequencies are found in New Zealand Maoris, New Caledonians and Kimberly Aborigines from Australia. Finally, this study may show a model of evolutionary factors acting and rising one HLA allele frequency (-A*24:02), but not in others that belong to the same or different HLA loci.  相似文献   

20.
There is a sharp difference in how one views TCR structure–function–behaviour dependent on whether its recognition of major histocompatibility complex‐encoded restriction elements (R) is germline selected or somatically generated. The generally accepted or Standard model is built on the assumption that recognition of R is by the V regions of the αβ TCR, which is not driven by allele specificity, whereas the competing model posits that recognition of R is allele‐specific. The establishing of allele‐specific recognition of R by the TCR would rule out the Standard model and clear the road to a consideration of a competing construct, the Tritope model. Here, the case for allele‐specific recognition (germline selected) is detailed making it obvious that the Standard model is untenable.  相似文献   

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