丙型肝炎病毒基因突变与免疫逃逸

免疫逃逸（Immune evasion）是指病原体逃避机体免疫监控的现象。在宿主和病毒的长期共同进化过程中,病毒形成了各种逃选机制以逃避宿主的免疫监控,其中病毒基因变异是最主要机制。丙型肝炎病毒（Hepatitis C virus,HCV）在感染个体中表现出极高的基因异质性,能有效地逃逸机体免疫识剐和破坏宿主免疫应答的能力,HCV还可侵袭免疫细胞来抑制机体的免疫功能,而建立HCV持续性感染。了解HCV病毒突变与免疫逃逸机制将会为预防和控制丙型肝炎提供依据。     

锁核酸SPC3649在HCV抗感染治疗中的研究进展

丙型肝炎病毒(HCV)是由约9.6kb个核苷酸组成的单股正链RNA病毒,属于黄病毒科丙型肝炎病毒属,被分为7个基因型及若干亚型。丙型肝炎是由HCV感染引起的常见血液传播型疾病,全球约有1.8亿人感染,引起慢性肝炎、肝硬化、肝癌。至今没有针对HCV的保护性疫苗,目前批准的标准治疗方式主要是聚乙二醇-干扰素(PEG-IFN)和利巴韦林(RBV)的联合疗法。目前这种疗法对不同基因型的感染患者的作用效果差异很大,对HCV基因2型及3型的患者,80%可以获得持续的病毒学应答反应(SVR),然而     

丙型肝炎病毒蛋白作用于细胞信号转导途径的研究进展

细胞信号转导异常往往与人类疾病的发生、发展密切相关。一些病毒致病和感染机制即为病毒抗原蛋白作用宿主细胞信号转导途径,导致宿主细胞内信号转导发生紊乱。丙型肝炎病毒（HCV）是引发慢性丙型肝炎,导致肝硬化和肝细胞癌发生的主要病原体,但目前HCV的致病机制与宿主内持续感染机制尚不清楚。HCV致病机制可能与HCV表达的蛋白质干扰宿主细胞信号转导途径而导致异常的细胞信号转导有关。研究HCV蛋白对宿主细胞信号转导途径的影响不仅有助于阐明其致病机制,还能为新药设计和寻找新的治疗方法提供新思路和新靶点。本文主要综述了近年来国内外有关HCV蛋白作用细胞信号转导途径的研究进展。     

干扰素-α治疗慢性乙型肝炎的疗效及其影响因素的研究

目的：分析影响干扰素-α（IFN-α）治疗慢性乙型肝炎（CHB）疗效的因素。方法：选择2006年到2009年青岛市传染病医院住院的CHB患者46例,应用IFN-α治疗48周,根据IFN-α治疗的疗效将其分为应答组与无应答组,评价患者的宿主、病毒载量及生化指标等因素对疗效的影响。结果：两组间的性别比例、年龄和病程无显著差异（P〉0.05）,应答组治疗前HBV-DNA载量低于无应答组,ALT水平高于无应答组,HBeAg阳性患者的应答率高于HBeAg阴性患者,差异均具有统计学意义（P〈0.05）,应答组在治疗12周时HBV-DNA载量下降〉2log的比例高于无应答组,差异具有统计学意义（P〈0.05）。结论：治疗前HBVDNA载量低、ALT水平高和HBeAg阳性以及治疗12周时的HBVDNA应答可以作为干扰素-α治疗慢性乙型肝炎48周时应答的预测因素。     

皖南地区丙型肝炎病毒治疗前后HVR1区碱基变异数量的研究

目的研究皖南地区丙型肝炎病毒治疗前后高变区1(HVR1)碱基变异数量与病情变化和治疗效果之间是否具有相关性。方法应用速率法和荧光定量PCR法,检测皖南地区141例慢性丙型肝炎患者血清ALT水平和HCV RNA的载量。应用RT-PCR法进行HCV基因型和治疗前后的HVR1区域序列的检测。结果 141例患者的血清ALT与HCV RNA两指标间采用Spearman等级相关分析显示,rs=0.213,P=0.011,差异具有统计学意义,存在正相关。通过HCV基因1型、2型和未分型3组的HVR1碱基变异数量的单因素方差分析,显示组与组之间差异具有统计学意义。结论慢性丙型肝炎患者治疗前后的HVR1序列碱基变异数量的分析,对治疗效果、病情变化及预后发展等方面的评估具有重要的指导意义。     

IL28B基因在乙型肝炎病毒感染中的作用

乙型肝炎病毒(Hepatitis B virus,HBV)感染是引发乙型肝炎的病因,慢性化程度较高,后期可诱发肝硬化甚至肝癌。IL28B基因属于新型干扰素λ家族,已有研究报道其遗传多态性与HBV感染者的治疗效果和病毒自然清除率具有相关性。通过探讨IL28B基因遗传易感性与HBV感染、患者治疗应答和病毒清除的关系,可以进一步了解宿主基因多态性在HBV感染治疗和病毒自然清除中的作用机制,为乙肝患者个体化医疗提供一定的理论基础。     

慢性丙型肝炎患者中丙型肝炎病毒准种变异研究进展

丙型肝炎病毒（HCV）具有较高的变异性,通常以准种的形式分布在感染者的体内,病毒容易逃离机体的免疫监控,因而无法被有效地清除,导致机体很难控制其感染的发展,故易转变成慢性肝炎。HCV准种变异在宿主体内的持续存在对病毒感染的控制、抗病毒药物和疫苗的发展都是一个巨大的挑战。,我们重点阐述近年来关于HCV准种变异及其与慢性丙型肝炎患者的机体免疫、疾病进展、治疗效果之间关系的研究进展。     

丙型肝炎炎症发生与细胞信号通路异常

丙型肝炎病毒(hepatitis C virus,HCV)感染是引起慢性丙型肝炎的直接原因,炎症的持续发生会导致肝纤维化、硬化甚至是肝癌的出现。炎症发生通常与细胞信号通路异常相关,病毒感染后病毒蛋白干扰宿主细胞正常的信号转导途径,使得促炎和炎症相关分子异常表达,导致炎症的发生。了解HCV感染后炎症发生的分子机制将有助于防止丙型肝炎炎症的恶化,为临床抗病毒治疗提供参考。     

IL28B基因在HCV感染中的作用和应用前景

丙型肝炎病毒(Hepatitis C virus, HCV)是造成慢性肝炎、肝硬化乃至肝癌的主要原因之一, 严重威胁人类健康。宿主因素可影响HCV的感染、治疗效果和自然清除率。近期, 欧美多个研究组对自愈和经过治疗的慢性丙型肝炎患者进行了全基因组关联分析(Genome-wide association study, GWAS), 证明IL28B基因(编码IFN-λ3)的单核苷酸多态位点(Single nucleotide polymorphism, SNP)影响HCV患者的治疗效果和自然清除率。IFN-λ3通过与其异源二聚受体IFN-λR1·IL-10R2结合进行信号传导, 上调干扰素刺激基因的表达, 进而发挥抗病毒、抑制肿瘤细胞生长以及免疫调节等生物学功能, 有望成为一种新型抗HCV药物。虽然IL28B基因SNP影响病毒清除的机制尚未清楚, 但其关联分析结果可作为HCV患者临床治疗的辅助指导, 对HCV患者进行IL28B基因遗传易感和功能研究将有助于该病的预防和治疗。     

丙型肝炎病毒准种及其临床意义研究进展

丙型肝炎病毒（HCV）易发生变异,在宿主体内主要以准种形式存在。HCV准种能够参与病毒逃避宿主的免疫监控及抗病毒治疗的耐药性,导致病毒在宿主体内持续存在,形成慢性感染。该文就HCV准种的产生、研究方法、基因组各区段内准种的研究及其临床意义作一综述。     

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.     

A Unique Protease Cleavage Site Predicted in the Spike Protein of the Novel Pneumonia Coronavirus (2019-nCoV) Potentially Related to Viral Transmissibility

正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases     

Curcuminoids as inhibitors of thioredoxin reductase: A receptor based pharmacophore study with distance mapping of the active site

Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.     

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.