Ⅱ型登革病毒前膜抗体对该病毒在THP-1细胞中复制能力的影响

目的探讨Ⅱ型登革病毒(dengue virusⅡ,DENVⅡ)前膜(presynaptic membrane,prM)抗体对DENVⅡ在THP-1细胞中复制能力的影响。方法采用不同稀释度(1/4~1/16 384)的DENVⅡanti-pr M单克隆抗体分别与不同MOI的DENVⅡ(MOI分别为3、0.75及0.19)复合感染THP-1细胞。建立DENVⅡ荧光定量PCR检测标准曲线,检测THP-1细胞培养上清液的病毒拷贝数。结果 DENVⅡ按MOI=3感染THP-1细胞,当prM稀释度为1/16和1/16 384时诱发THP-1细胞产生病毒的载量较高,prM稀释度为1/64和1/256时抑制病毒生长;DENVⅡ按MOI=0.75感染THP-1细胞,当prM稀释度1/16时可诱发更高浓度病毒载量;DENVⅡ按MOI=0.19感染THP-1细胞时,不会诱导产生高浓度的病毒载量。结论中浓度pr M抗体可抑制DENVⅡ在THP-1细胞中的复制能力,而高及低浓度prM抗体可促进DENVⅡ在THP-1细胞中的复制能力。     

神经时代中的光遗传学技术

光遗传学技术是将光学技术和遗传学结合的一种变革性研究方法,其独特的双向控制具有较高的空间和时间分辨率。该技术通过特定光刺激光敏感蛋白在短时间内激活或沉默特定细胞和神经回路,研究大脑功能异常的机制,并确定行为障碍的病因,为神经疾病的研究提供了理论指导,被认为是神经科学研究的理想工具。现总结了目前光遗传学技术在阿尔兹海默病、帕金森病、亨廷顿舞蹈症、癫痫等神经性疾病中的研究价值,以及在相关研究中的优点和尚未解决的问题,最终帮助研究者探究发病机制并寻找高效治疗策略。     

Ⅲ型登革病毒在C6/36及Vero细胞中复制对其毒力的影响

目的探讨Ⅲ型登革病毒(dengue virus,DENV)在C6/36和Vero细胞中复制对其毒力的影响。方法将DV3-1及DV3-2两株Ⅲ型DENV在C6/36细胞上接种传代培养,待其毒力稳定再接种至Vero细胞连续传代培养。用Ⅲ型DENV标准质粒检测不同代次病毒拷贝数,PCR扩增获得传代毒种全长基因序列,并与原代病毒基因序列进行比对。结果 DV3-1在C6/36细胞上传代至第17代次(P17-C6/36)时毒力保持稳定,DV3-2在盲传过程中均未见明显的细胞病变;将DV3-1和DV3-2第17代次病毒在Vero细胞上继续传代,DV3-1传至第10代次(P10-Vero)CPE为40%,DV3-2传至第4代次CPE达30%。DV3-1在P17-C6/36时具有较高的病毒拷贝数,在P0(原代病毒)及P10-Vero时病毒拷贝数偏低。与P0比较,P17-C6/36及P10-Vero全长碱基共16处发生突变,导致12个氨基酸的非同义突变,其中P0和P10-Vero在第5 826、6 251、7 907位点碱基相同,P17-C6/36相应的氨基酸位点(第1 942、2 084、2 636位点)均发生非同义突变。结论传代细胞更换可对Ⅲ型DENV的毒力造成影响,多次传代及更换细胞传代后仍可能发生回复突变。本研究为后续DENV减毒策略的研究提供了实验依据。     

全基因组关联分析在植物中的应用

全基因组关联分析(GWAS)已被广泛应用到植物遗传学和育种相关的重要性状研究中。关联分析是一种基于连锁不平衡来识别分子标记之间或候选基因与性状之间关系的方法。简单介绍了GWAS的发展背景、研究原理及研究策略,对GWAS在重要的植物基因位点方面的应用研究进展进行了综述。     

2017年云南省登革病毒Ⅰ型分离株NS1基因的鉴定及分析

目的鉴定并分析2017年云南省登革病毒Ⅰ型(dengue virusⅠ,DENVⅠ)分离株的NS1基因。方法采用病毒RNA提取试剂盒提取登革热(dengue fever,DF)患者血清RNA,RT-PCR法鉴定病毒类型,并扩增DENVⅠ的NS1基因,进行测序。应用BIOEDIT软件比对NS1及DENVⅠ标准株(DQ672562.1)的核苷酸及氨基酸序列,并进行突变分析。应用MEGA 5.1软件中的NJ法(1000 Boot strap replicate)构建NS1基因的系统进化树。结果共分离获得16株DENVⅠ的NS1基因,经比对发现,201703、201704、201708、201709、201713分离株NS1基因第21位碱基由C变为T(无义突变);201705、201706、201712分离株NS1基因第289位碱基由T变为A(有义突变),氨基酸曲L变为M。16株分离株NS1基因其他突变位点均相同,共85处发生碱基突变,其中5个为有义突变。16株分离株与2011-China Donggua(JQ048541.1)、2008-Singapore(GU370049.2)、2014-Taiwan(KU365900.1)、2005-China Fujian(DQ193572.1)、2016-Malaysia(KX452065.1)、2007-Indonesia(KC762646.1)、2015-South Korea(KP406802.1)、2006-Japan(AB178040.1)、2007-Thailand(HM469966.1)、2013-singapore(KJ806945.2)有较近的亲缘关系。结论 2017年云南省16株分离毒株均为DENVⅠ,可能属于东南亚国家的输入性毒株。     

地方院校农学专业遗传学课程教学改革的几点思考

遗传学是农学专业重要的专业基础课之一,遗传学实验教学是遗传学课程必要的组成部分,二者的有机结合对培养农学专业特色人才具有重要作用。本文结合教学改革实际内容,阐述了湖南文理学院生命科学学院农学专业遗传学理论及实验课的教学改革实践。     

反向遗传学技术在流感病毒研究及流感疫苗发展中的应用

流感病毒是分节段负链RNA病毒,属于有包膜的正黏病毒科,分为甲、乙、丙、丁4个型别。流感病毒可引起流感季节性流行或大流行,导致严重的公共卫生和经济问题,接种疫苗可有效预防流感病毒的感染。反向遗传学技术对扩大人类对流感病毒的分子生物学和发病机制的认识产生了重要影响,通过突变流感病毒基因组中的特定核苷酸,阐明流感病毒基因组序列调控性质或特定氨基酸对流感病毒蛋白功能的作用。通过反向遗传学技术可将两种或多种病毒遗传物质进行重组,共感染细胞制备出重组病毒株,作为季节性流感疫苗或针对潜在大流行病毒株的疫苗。本文对流感反向遗传学技术在流感病毒研究及流感疫苗发展中的应用作一综述。     

乙脑/登革2型嵌合病毒的构建及其作为疫苗候选株的初步检定

目的构建以乙脑疫苗株SA14-14-2为基因骨架的乙脑/登革2型嵌合病毒,并进行初步检定,分析其作为疫苗候选株的可行性。方法用登革病毒(dengue virus,DENV)减毒株PDK53 prME基因替换乙脑病毒疫苗株SA14-14-2的相应区域,构建乙脑/登革2型嵌合病毒全长克隆质粒,通过体外转录、转染原代地鼠肾(PHK)细胞,拯救出乙脑/登革2型嵌合病毒,并分析该嵌合病毒的蚀斑特征、增殖特征、神经毒力和神经侵袭力、免疫原性及免疫攻击保护作用。结果构建的嵌合病毒比乙脑疫苗株SA14-14-2具有更小的蚀斑,在PHK细胞上具有更低的增殖能力;对成鼠无神经毒力和神经侵袭力;可诱导小鼠产生较高的中和抗体效价,且免疫8周后,中和抗体滴度无明显下降(P 0. 05);能保护小鼠免受致死剂量DENV的脑内攻击。结论本实验制备的嵌合病毒具有良好的安全性、免疫原性及免疫保护作用,有望作为登革疫苗候选株。     

蓝藻生物燃料研究获进展

日前,中科院青岛生物能源与过程研究所生物代谢工程团队在基因工程蓝藻合成乙醇、脂肪醇、脂肪烃的系列研究中结出硕果,技术上实现了生物燃料分子在单一光合蓝藻细胞内的合成,并证明了通过代谢工程和遗传学相关技术提高蓝藻生物燃料合成的潜力,为基因工程蓝藻高效制备生物液体燃料的进一步发展奠定了基础。     

2013—2022年吉林省部分麻疹确诊病例中其他病毒共感染情况分析

目的 分析2013—2022年吉林省部分麻疹确诊病例中发热伴出疹及其他呼吸道病毒的共感染情况,为麻疹合并感染多病原诊断提供科学依据。方法 收集2013—2022年吉林省106份麻疹确诊病例咽拭子标本,针对水痘-带状疱疹病毒(varicella-zoster virus,VZV)、登革病毒(Dengue virus,DENV)、人类细小病毒B19(human parvovirus B19,HPV-B19)、EB病毒(Epstein-Barr virus,EBV)、人疱疹病毒6型(human herpesvirus6,HHV6)、人鼻病毒(human rhinovirus,HRV)、呼吸道合胞病毒(respiratory syncytial virus,RSV)、人腺病毒(human adenovirus,HAdV)、巨细胞病毒(human cytomegalovirus,HCMV)9种发热伴出疹相关病毒及呼吸道病毒进行荧光定量PCR检测,并应用SPSS 23.0软件进行统计学分析。结果 106份标本中,未检出VZV及DENV,其他7种病毒均有检出。30.18%的麻疹病例存在与其他病毒共感...     

Imidazolidinones and Imidazolidine-2,4-diones as Antiviral Agents

Imidazolidinones and imidazolidine-2,4-diones are important classes of heterocyclic compounds that possess potent activities against several viruses such as dengue virus, enterovirus, hepatitis C virus (HCV), and human immunodeficiency virus (HIV). The first imidazolidinone derivative as an anti-HIV agent was reported in 1996. Imidazolidinones inhibit HIV aspartic protease activity, and also act as CCR5 co-receptor antagonists. Significant effort has been devoted to the design of various imidazolidinone analogues that are active against drug-resistant HIV strains, with fewer side effects. Different scaffolds have been designed through both rational drug design strategies and computer-aided drug design. Imidazolidinones have been found to be potent against HIV, and preclinical studies are currently in progress. There are some reports of imidazolidinones as having both anti-HCV and anti-dengue virus activity, and more research has yet to be done along these lines. These compounds inhibit NS3 serine protease of HCV, and NS2B-NS3 protease of dengue virus. Pyridyl-imidazolidinones possess very specific and potent activity against human enterovirus 71 (EV71) by targeting the EV71 capsid protein VP1, and inhibiting viral adsorption and/or viral RNA uncoating.     

西尼罗热疫苗的研究进展

西尼罗病毒感染可导致轻微或严重的疾病甚至死亡,对人畜健康危害较大。疫苗是预防西尼罗病毒感染的重要手段。近年来,西尼罗热疫苗的研究取得了重大进展,尤其是反向遗传学技术的应用进一步加快了其研发进程。本文就近几年西尼罗热疫苗的研究进展作一综述。     

活性炭的制备及其应用进展

对植物性活性炭的基本结构、性能、性质和特点进行了概述,介绍了国内外活性炭生产的主要技术路线、研究开发的现状与发展趋势。指出农用废弃物应成为制备植物性活性炭的重要来源,微波辐射技术在活性炭的制备及其结构改造方面的应用具有发展前景。着重综述了提高活性炭吸附性能的有效途径及其在净水处理、废水处理、气相吸附等方面的应用研究进展,并指出了活性炭应用领域中有待解决的问题和今后的发展方向。     

Studying SARS-CoV-2 with Fluorescence Microscopy

The COVID-19 pandemic caused by SARS-CoV-2 coronavirus deeply affected the world community. It gave a strong impetus to the development of not only approaches to diagnostics and therapy, but also fundamental research of the molecular biology of this virus. Fluorescence microscopy is a powerful technology enabling detailed investigation of virus–cell interactions in fixed and live samples with high specificity. While spatial resolution of conventional fluorescence microscopy is not sufficient to resolve all virus-related structures, super-resolution fluorescence microscopy can solve this problem. In this paper, we review the use of fluorescence microscopy to study SARS-CoV-2 and related viruses. The prospects for the application of the recently developed advanced methods of fluorescence labeling and microscopy—which in our opinion can provide important information about the molecular biology of SARS-CoV-2—are discussed.     

Instability of the NS1 Glycoprotein from La Reunion 2018 Dengue 2 Virus (Cosmopolitan-1 Genotype) in Huh7 Cells Is Due to Lysine Residues on Positions 272 and 324

La Reunion island in the South West Indian Ocean is now endemic for dengue following the introduction of dengue virus serotype 2 (DENV-2) cosmopolitan-I genotype in 2017. DENV-2 infection causes a wide spectrum of clinical manifestations ranging from flu-like disease to severe dengue. The nonstructural glycoprotein 1 (NS1) has been identified as playing a key role in dengue disease severity. The intracellular NS1 exists as a homodimer, whereas a fraction is driven towards the plasma membrane or released as a soluble hexameric protein. Here, we characterized the NS1 glycoproteins from clinical isolates DES-14 and RUN-18 that were collected during the DENV-2 epidemics in Tanzania in 2014 and La Reunion island in 2018, respectively. In relation to hepatotropism of the DENV, expression of recombinant DES-14 NS1 and RUN-18 NS1 glycoproteins was compared in human hepatoma Huh7 cells. We observed that RUN-18 NS1 was poorly stable in Huh7 cells compared to DES-14 NS1. The instability of RUN-18 NS1 leading to a low level of NS1 secretion mostly relates to lysine residues on positions 272 and 324. Our data raise the issue of the consequences of a defect in NS1 stability in human hepatocytes in relation to the major role of NS1 in the pathogenesis of the DENV-2 infection.     

Successful and Safe Long-Term Standard Antiviral Therapy in a Patient with “Explosive” Immune Response in Course of HCV-Related Liver Cirrhosis

Hepatitis C virus (HCV) has been recognized to be both a hepato- and lymphotropic virus. HCV lymphotropism represents an essential detail in the pathogenesis of virus-related autoimmune and lymphoproliferative disorders, ranging from clonal expansion of B-cells with organ and non-organ-specific autoantibody production up to overt non-Hodgkin’s lymphoma along a continuous step-by-step model of B-cell lymphomagenesis, where the intermediated mixed cryoglobulinemia could be considered as a stage of suppressible antigen-driven lymphoproliferation. The HCV long-lasting extrahepatic replicative state generates an abnormal systemic immunological response, including rheumatoid factor (RF) and cryo- and non-cryoprecipitable immune complexes, as well as clinical manifestations, comprising dermatitis, polyarthralgias and arthritis, pulmonary disease, aplastic anemia, glomerulonephritis and vasculitis. The mechanism of these extra-hepatic disorders is thought of as linked to immune complex disease, but their pathogenesis is poorly clarified. Immune-suppressive treatment could induce high-level hepatitis C viremia and impair hepatic disease. We report a female patient, whose chronic HCV-related liver cirrhosis with associated explosive, but oligosymptomatic lymphoproliferative immune response, i.e., RF beyond three thousand times the upper of normal range (unr), type II cryoglobulinemia with cryocrit 40% and monoclonal gammopathy IgM-k, has been successfully and safely treated by long-lasting (sixty-six months) combined antiviral therapy (pegylated interferon alfa and ribavirin), at moderate and tapering dose regimen, prolonged for nearly 24 months after the first viral suppression. At the last follow-up (fifty-one months), the patient was showing very-long term antiviral response, progressive decline of secondary immune activation and absence of significant side-effects. Further research is required to fully verify the real impact on therapeutic choice/regimen.     

Development and Characterization of a Multiplex Assay to Quantify Complement-Fixing Antibodies against Dengue Virus

Antibodies capable of activating the complement system (CS) when bound with antigen are referred to as “complement-fixing antibodies” and are involved in protection against Flaviviruses. A complement-fixing antibody test has been used in the past to measure the ability of dengue virus (DENV)-specific serum antibodies to activate the CS. As originally developed, the test is time-consuming, cumbersome, and has limited sensitivity for DENV diagnosis. Here, we developed and characterized a novel multiplex anti-DENV complement-fixing assay based on the Luminex platform to quantitate serum antibodies against all four serotypes (DENV1-4) that activate the CS based on their ability to fix the complement component 1q (C1q). The assay demonstrated good reproducibility and showed equivalent performance to a DENV microneutralization assay that has been used to determine DENV serostatus. In non-human primates, antibodies produced in response to primary DENV1-4 infection induced C1q fixation on homologous and heterologous serotypes. Inter-serotype cross-reactivity was associated with homology of the envelope protein. Interestingly, the antibodies produced following vaccination against Zika virus fixed C1q on DENV. The anti-DENV complement fixing antibody assay represents an alternative approach to determine the quality of functional antibodies produced following DENV natural infection or vaccination and a biomarker for dengue serostatus, while providing insights about immunological cross-reactivity among different Flaviviruses.     

膜法在镀镍漂洗废水处理中的应用

膜技术已经广泛应用于水处理工艺中。采用膜分离技术浓缩镀镍漂洗水以及回收利用漂洗水中的镍和水资源,可以带来显著的社会效益。文章主要介绍了纳滤膜、反渗透膜、集成膜处理电镀镍漂洗废水,并提出了膜分离技术将会在电镀废水处理中占据重要的地位。     

Identification of Broad‐Spectrum Dengue/Zika Virus Replication Inhibitors by Functionalization of Quinoline and 2,6‐Diaminopurine Scaffolds

Social and demographic changes across the world over the past 50 years have resulted in significant outbreaks of arboviruses such as dengue virus (DENV) and Zika virus (ZIKV). Despite the increased threat of infection, no approved drugs or fully protective vaccines are available to counteract the spread of DENV and ZIKV. The development of “broad‐spectrum” antivirals (BSAs) that target common components of multiple viruses can be a more effective strategy to limit the rapid emergence of viral pathogens than the classic “one‐bug/one‐drug” approach. Starting from previously identified multitarget DENV inhibitors, herein we report the identification of novel 2,6‐diaminopurine derivatives that are able to block the replication of both Zika virus and all serotypes of dengue virus (DENV 1–4) in infected cells.