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细小病毒B19是目前细小病毒家族中除人博卡病毒(HBoV)和新型细小病毒PARV4(Humanparvovirus 4)以外唯一可以引起人类疾病的病毒。它可能是多种疾病的致病因子,感染儿童可引起传染性红斑,感染成人可引起多发性关节病综合征,而对一些有免疫病,血液病的患者,B19感染可以引起严重的疾病,如慢性红细胞贫血,暂时性再障危象。病毒感染后对细胞的毒性是引起暂时性障碍危象和纯红细胞再障的直接原因。血液病患者中,B19病毒感染是引起暂时性障碍危象的主要病因,持续B19病毒感染会导致免疫缺损患者 相似文献
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细小病毒B19诊断芯片的初步研究 总被引:1,自引:0,他引:1
初步探讨并制备细小病毒B19诊断芯片,进行实验室验证.用基因芯片点样仪将细小病毒B19诊断探针固定在特殊处理的玻片上,以细小病毒B19质粒重复检测.运用限制性显示(RD)技术,用Cy5标记的通用引物进行荧光标记,通过与基因芯片杂交,严谨洗涤,将非特异性的标记片段洗脱后,经扫描仪扫描,计算机解读.杂交结果显示,Cy5标记的探针均出现杂交信号,而阴性对照和空白对照的杂交信号均很弱:芯片检测具有高特异性、敏感性和可重复性.初步建立了较可靠的制备与检测细小病毒B19诊断芯片的方法,经验证诊断准确率高,假阳性率低. 相似文献
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RNA病毒基因组和转录复制多样性的分子基础 总被引:1,自引:0,他引:1
自然界中RNA病毒的种类和数量比DNA病毒多得多,根据基因组类型,RNA病毒可分为多种类型,许多研究者认为,存在于古细菌Myxobacteria中,仅仅有一个逆转录酶基因的反转子(Retron)可能是所有病毒的祖先,进化的模式如下,反转子→反座子→反转录转座子→反转录病毒→副反转录病毒→DNA病毒,RNA病毒转录。/复制在很多特征上与DNA病毒迥然不同,依赖于RNA的RNA聚合酶是RNA病转录/复制的主要催化剂,RNA病毒基因组转录和复制都从3'端poly(A)或类tRNA结构或其他结构起始,内部终止是转录,通读到5'末端终止是复制,RNA病毒的模板有正链病毒(RNA模板,负链病毒RNA模板和全长正负链反基因组RNA模板,RNA模板的选择调控机制非常复杂,目前知之甚少,选择模板,RNA聚合酶与转录因子结合形成复制体是两种主要的调控方法,另外,5'UTR和3'UTR也可以调控RNA病毒的转录。 相似文献
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人博卡病毒1 (human bocaparvovirus 1, HBoV1)为感染人并引起疾病的两种细小病毒之一。其感染2−5岁婴幼儿,能引起轻度或重度急性呼吸道疾病,严重时可危及生命。HBoV1基因组末端含末端反向重复序列(repeat the sequence in reverse, ITR),为病毒基因组复制所必需,但是难以进行PCR扩增合成。本研究通过分步合成末端ITR及分子克隆方法成功构建HBoV1的全长感染性克隆pSKHBoV1。经转染HEK293细胞后,分别从重要非结构蛋白的表达、病毒RNA转录后修饰与加工、病毒基因组复制水平以及子代病毒粒子基因组鉴定等方面,证实构建的感染性克隆在转染HEK293细胞后能够进入正常的复制周期并具有拯救出病毒粒子的潜力,这为后续研究HBoV1的复制增殖、病毒与宿主互作关系以及病毒疫苗的研发奠定了基础。 相似文献
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无菌留取 5 4例自然流产妇女和 43例妊娠无异常孕妇血清 ,用聚合酶链反应 (PolymeraseChainReaction ,PCR)检测的人细小病毒B19(HumanParvovirusB19,B19)DNA ,在自然流产组中人细小病毒B19DNA有 15例阳性 ,阳性率为 2 7.78%。正常对照组中 ,人细小病毒B19DNA有 2例为阳性 ,阳性率为 4.65 % ,用x2 检验 ,x2 =8.86,P <0 .0 1,两组有非常显著性差异。由此总结 ,人细小病毒B19感染可能是导致自然流产的原因之一 相似文献
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本文介绍病毒编码的启动子和增强子的结构和功能特点。综述人类免疫缺陷病毒,人单纯疱疹病毒,巨细胞病毒,人乳头瘤病毒,Epstein-Barr病毒和乙型肝炎病毒启动子和增强子研究的主要进展,阐述这些启动子,增强子在病毒转录及调控中的作用及其机制和目前研究中有待解决的问题。 相似文献
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采用昆虫杆状病毒表达系统,制备人细小病毒B19病毒样颗粒(VLPs)。先通过PCR方法合成细小病毒B19衣壳蛋白基因VP2,将其克隆到pFastBac1质粒,然后转化含杆状病毒穿梭载体Bacmid的E.coliDH10Bac感受态细胞,获得重组杆状病毒表达质粒Bacmid-VP2。在脂质体介导下转染Sf9昆虫细胞,包装重组杆状病毒rBac-VP2。利用rBac-VP2感染Sf9细胞表达B19VP2蛋白,通过间接免疫荧光、Western blotting等方法鉴定目的蛋白表达。采用两次超速离心的方法对表达产物进行纯化,纯化产物在透射电镜下可见直径约22nm的VLPs。本研究成功制备了人细小病毒B19的VLPs,为B19感染血清学检测方法的建立提供了参考。 相似文献
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The B19 virus can persist in immunocompromised patients for several months and sometimes even years because of impaired immune
response. Viremia in persistent and recurrent infection may range from very low to high titers and may be associated with
chronic clinical manifestations, such as chronic anemia.
Several recently developed techniques that quantify B19-DNA have improved laboratory diagnosis of the infection and can help
guide the choice of treatment in persistent infections (i.e., intravenous immunoglobulin (IVIG) treatment vs immunosuppression
reduction).
Here we describe the development of a reliable internally controlled quantitative competitive (QC)-polymerase chain reaction
(PCR) assay that measures B19-DNA load in serum samples by densitometric analysis of the amplification products for monitoring
B19 infection in high-risk patients. A retrospective quantification of B19-DNA in the serum samples from 48 anemic transplanted
patients by the QC-PCR assay we developed in our laboratory confirmed the presence of B19-DNA in 11 of 48 samples and showed
a viral DNA load between 103 and 108 B19-DNA copies/mL depending on the patients' serostatus (the highest viral load was found in IgM-positive/IgG-negative patients
that is, in patients with active B19 infection at onset). The assay also confirmed B19-DNA negative patients. Our QC-PCR assay
may be easily relation between active B19 infection and occurrence of anemia and to assess the efficacy of IVIG therapy or
immunosuppression reduction in clearing the virus in high-risk patients. 相似文献
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Molecular and functional analyses of a human parvovirus B19 infectious clone demonstrates essential roles for NS1, VP1, and the 11-kilodalton protein in virus replication and infectivity 下载免费PDF全文
In an attempt to experimentally define the roles of viral proteins encoded by the B19 genome in the viral life cycle, we utilized the B19 infectious clone constructed in our previous study to create two groups of B19 mutant genomes: (i) null mutants, in which either a translational initiation codon for each of these viral genes was substituted by a translational termination codon or a termination codon was inserted into the open reading frame by a frameshift; and (ii) a deletion mutant, in which half of the hairpin sequence was deleted at both the 5' and the 3' termini. The impact of these mutations on viral infectivity, DNA replication, capsid protein production, and distribution was systematically examined. Null mutants of the NS and VP1 proteins or deletion of the terminal hairpin sequence completely abolished the viral infectivity, whereas blocking expression of the 7.5-kDa protein or the putative protein X had no effect on infectivity in vitro. Blocking expression of the proline-rich 11-kDa protein significantly reduced B19 viral infectivity, and protein studies suggested that the expression of the 11-kDa protein was critical for VP2 capsid production and trafficking in infected cells. These findings suggest a previously unrecognized role for the 11-kDa protein, and together the results enhance our understanding of the key features of the B19 viral genome and proteins. 相似文献
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Novoa RR Calderita G Arranz R Fontana J Granzow H Risco C 《Biology of the cell / under the auspices of the European Cell Biology Organization》2005,97(2):147-172
Genome replication and assembly of viruses often takes place in specific intracellular compartments where viral components concentrate, thereby increasing the efficiency of the processes. For a number of viruses the formation of 'factories' has been described, which consist of perinuclear or cytoplasmic foci that mostly exclude host proteins and organelles but recruit specific cell organelles, building a unique structure. The formation of the viral factory involves a number of complex interactions and signalling events between viral and cell factors. Mitochondria, cytoplasmic membranes and cytoskeletal components frequently participate in the formation of viral factories, supplying basic and common needs for key steps in the viral replication cycle. 相似文献
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目的:研究TNF-α基因单核苷酸多态性(SNP)308G—A位点与新疆地区维吾尔族人乙型肝炎之间的关系。方法:以聚合酶链式反应-限制性内切酶长度多态性(PCR-RFLP)技术,对120例乙肝患者和120例正常对照者TNF—α基因SNP308多态性位点进行基因分型。结果:SNP308多态性位点G/G基因型和G/A基因型频率在病例组为77%和23%,正常对照组为88%和12%,2组基因型和等位基因频率分布差异有显著性(p〈0.05)。结论:TNF—α基因启动子308多态性位点与新疆维吾尔族人乙肝有明显相关性。 相似文献
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Novel transcription map for the B19 (human) pathogenic parvovirus 总被引:30,自引:15,他引:15
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对虾病毒病研究现状 总被引:1,自引:0,他引:1
对虾病毒病已严重危害世界对虾养殖业的发展,引起国内外学者的广泛关注。对近几年来对虾病毒病的研究现状和动态进行了概述,重点介绍了杆状病毒科(Baculoviridae)、细小病毒科(Parvoviridae)、呼肠孤病毒科(Reoviridae)、虹彩病毒科(Iridoviridae)、小RNA病毒科(Picornaviridae)、弹状病毒科(Rhabdoviridae)、被膜病毒科(Togaviridae)等几个科15种对虾病毒的特征、临床症状、病理特征、宿主范围和主要检测方法;对病毒病的传播途径、防治措施和存在的问题也进行了简要介绍。 相似文献
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Keval Bollavaram Tiffanie H. Leeman Maggie W. Lee Akhil Kulkarni Sophia G. Upshaw Jiabei Yang Hannah Song Manu O. Platt 《Protein science : a publication of the Protein Society》2021,30(6):1131
SARS‐CoV‐2 is the coronavirus responsible for the COVID‐19 pandemic. Proteases are central to the infection process of SARS‐CoV‐2. Cleavage of the spike protein on the virus''s capsid causes the conformational change that leads to membrane fusion and viral entry into the target cell. Since inhibition of one protease, even the dominant protease like TMPRSS2, may not be sufficient to block SARS‐CoV‐2 entry into cells, other proteases that may play an activating role and hydrolyze the spike protein must be identified. We identified amino acid sequences in all regions of spike protein, including the S1/S2 region critical for activation and viral entry, that are susceptible to cleavage by furin and cathepsins B, K, L, S, and V using PACMANS, a computational platform that identifies and ranks preferred sites of proteolytic cleavage on substrates, and verified with molecular docking analysis and immunoblotting to determine if binding of these proteases can occur on the spike protein that were identified as possible cleavage sites. Together, this study highlights cathepsins B, K, L, S, and V for consideration in SARS‐CoV‐2 infection and presents methodologies by which other proteases can be screened to determine a role in viral entry. This highlights additional proteases to be considered in COVID‐19 studies, particularly regarding exacerbated damage in inflammatory preconditions where these proteases are generally upregulated. 相似文献
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A reverse genetics approach for recovery of recombinant influenza B viruses entirely from cDNA 总被引:2,自引:0,他引:2 下载免费PDF全文
The recovery of recombinant influenza A virus entirely from cDNA was recently described (9, 19). We adapted the technique for engineering influenza B virus and generated a mutant bearing an amino acid change E116G in the viral neuraminidase which was resistant in vitro to the neuraminidase inhibitor zanamivir. The method also facilitates rapid isolation of single-gene reassortants suitable as vaccine seeds and will aid further investigations of unique features of influenza B virus. 相似文献