A型流感病毒H5N1

1.何谓禽流感? 禽流感是由正粘病毒科A型流感病毒引起的一种禽类感染综合症,主要感染家禽,也可感染人。根据病毒核蛋白(NP)和基质蛋白(MS)抗原性的不同,将流感病毒分成A、8、C三个型。A型流感病毒除感染禽类之外,还可感染猪、马和人类;B型和C     

甲型H1N1流感患儿免疫球蛋白水平变化

目的探讨甲型H1N1流感患儿免疫球蛋白水平变化及临床意义。方法采用放射免疫法检测51例甲型H1N1流感患儿（其中非危重组31例,危重组20例）急性期和恢复期以及对照组25例健康儿童外周静脉血的Ig,A、IgG、IgM、C3水平,并对结果进行分析。结果非危重组急性期和恢复期及对照组血清IgA、IgG、C3水平两两比较,差异均无统计学意义（P〉0．05）;危重组急性期血清IgA、IgG、C3水平低于非危重组急性期和对照组（P〈0．05）,恢复期血清IgA、I如、C3水平上升,与急性期比较差异有统计学意义（P〈0．05）;危重组和非危重组恢复期血清IsA、Is,G、C3水平比较,差异无统计学意义（P〉0．05）。非危重组、危重组及对照组血清IgM两两比较,差异无统计学意义（P〉0．05）。结论甲型H1N1流感患儿免疫球蛋白水平变化与病情严重性有关,危重患儿表现为急性期血清IgA、IgG、C3水平降低,恢复期恢复正常,提示危重甲型H1N1患儿体液免疫抑制是暂时的、可逆的。     

人源甲型H1N1流感HA基因进化特征分析

为了探究2009年3月至8月流感大爆发期间的人源甲型H1N1流感病毒的进化特征,提出了一种图形化表达病毒序列的方法,该方法将甲型H1N1流感病毒HA基因的符号序列数字化表达后,利用主成分分析（PCA）将高维数值序列的维度大幅度降低为二维,将低维的数值序列图形化表达在平面和空间中。在序列的图形化表达基础上,对2009年3月到8月收集的三千多个流感病毒样本做了新旧病毒的区分,筛选出了新型病毒菌株,并根据图形探究了甲型H1N1流感病毒在时间序列上的进化特征。     

甲型H1N1流感在预防控制措施下的传播数学模型构建

从数学应用的角度,研究甲型H1N1流感的传播规律,将人群分为易感人群、病毒潜伏人群、发病人群、退出者人群四类. 分析了甲型H1N1流感在人群间的转化过程;日接触率和"聚集性突然爆发"事件被数学刻画,尝试性地构建了一个在预防控制阶段的传播数学模型.     

关于甲型H1N1流感防控的探讨

本文主要介绍甲型H1N1流感的特性,并结合工作实际对甲型H1N1流感的防控作了深入的探讨,对于群发性传染疾病的预防护理给出指导性意见。     

1例重症甲型H1N1流感产妇的护理

2009年12月13日我科收治重症甲型H1N1流感产妇1例,经积极抗病毒、对症、支持等治疗及精心护理,住院治疗10 d,病情痊愈出院,现将护理体会报告如下。1病例介绍患者女性,20岁,农民,"因咳嗽6 d,发热3 d,呼吸困难25 h"于2009年12月13日01:00入     

我校甲型H1N1流感流行期的学生管理

本文主要总结2009年至2010年"甲流"流行期的学校管理,重点介绍了学校各部门的主要职责划分、措施及各部门之间的协调与配合,在发生公告卫生事件时更好的为学生和社会服务,从容应对突发事件,确保学校的安全与稳定.     

简述甲型(H1N1)流感疫情

一场突如其来的猪流感疫情在2009年4月13日起在墨西哥蔓延.墨西哥于2009年4月26日晚宣布,墨西哥确认和疑似死于猪流感的总人数升至103人,继之很快上升到1 300人.     

阿昔洛韦联合左氧氟沙星治疗甲型H1N1流行性感冒临床分析

目的 总结200910-201002发生在山西大同大学的甲型H1N1流行性感冒患者临床特征及治疗过程,以期为今后的甲型H1N1流行性感冒防治工作提供一定的临床经验.方法 研究对象为200910-201002期间在山西大同大学校医院确诊并治疗的254例甲型H1N1流行性感冒患者,用阿昔洛韦联合左氧氟沙星综合治疗,采用SPSS 11.0软件进行统计学分析.结果 248例患者治疗3～5d体温基本恢复正常,6例加用司他韦,体温恢复略快.结论 阿昔洛韦联合左氧氟沙星综合治疗甲型H1N1流感病毒患者有效,对于无基础疾病及肺部无明显实变倾向的患者均能治愈.     

血清浓度对MDCK细胞低密度培养的影响研究

目的:确定血清浓度对犬肾细胞(MDCK)培养的影响.方法:在DMEM培养基中添加了2%、5%、8%、10%的新生牛血清,以10个/cm2密度接种MDCK细胞培养后通过细胞集落计数,计算贴壁率.结果:不同血清浓度培养MDCK细胞均能形成明显的细胞集落,贴壁率分别为23.15%、43.17%、61.00%、74.89%.结论:血清浓度对MDCK细胞集落的形成及细胞贴壁率有明显的影响,8%和10%血清的贴壁率较高,适合该细胞培养.     

Genome evolution of novel influenza A （H1N1 ） viruses in humans

The epidemic situation of A H1N1 flu arose in North America in April 2009, which rapidly expanded to three continents of Europe, Asia and Africa, with the risk ranking up to 5. Until May 13th, the flu virus of A H1N1 had spread into 33 countries and regions, with a laboratory confirmed case number of 5728, including 61 deaths. Based on IRV and EpiFluDB database, 425 parts of A H1N1 flu virus sequence were achieved, followed by sequenced comparison and evolution analysis. The results showed that the current predominant A H1N1 flu virus was a kind of triple reassortment A flu virus： （i） HA, NA, MP, NP and NS originated from swine influenza virus; PB2 and PA originated from bird influenza virus; PB1 originated from human influenza virus. （ii） The origin of swine influenza virus could be subdivided as follows： HA, NP and NS originated from classic swine influenza virus of H1N1 subtype; NA and MP originated from bird origin swine influenza virus of H1N1 subtype. （iii） A H1N1 flu virus experienced no significant mutation during the epidemic spread, accompanied with no reassortment of the virus genome. In the paper, the region of the representative strains for sequence analysis （A/California/04/2009 （H1N1） and A/Mexico/4486/2009 （H1N1）） included USA and Mexico and was relatively wide, which suggested that the analysis results were convincing.     

Structure modeling and spatial epitope analysis for HA protein of the novel H1N1 influenza virus

In recent months, a novel influenza virus H1N1 broke out around the world. With bioinformatics technology, the 3D structure of HA protein was obtained, and the epitope residues were predicted with the method developed in our group for this novel flu virus. 58 amino acids were identified as potential epitope residues, the majority of which clustered at the surface of the globular head of HA protein. Although it is located at the similar position, the epitope of HA protein for the novel H1N1 flu virus has obvious differences in the electrostatic potential compared to that of HA proteins from previous flu viruses.     

H5N1亚型禽流感病毒血凝素基因的克隆与表达

 根据已知H5N1亚型禽流感病毒血凝素(HA)基因序列设计、合成克隆引物.自灭活的云南地方H5N1亚型病毒阳性临床组织样品中提取总RNA,反转录后采用高可信度DNA聚合酶(Pyobest^TMDNA Polymerase)扩增HA基因,采用Invitrogen定向表达系统(Champion^TMpET directional TOPO expression system)进行克隆表达,纯化获得N末端携带多聚组氨酸标签的重组HA,分子质量约78ku.采用阳性血清经免疫印迹及ELISA分析重组HA的免疫反应性,结果表明重组HA能与H5N1亚型病毒抗血清发生特异性结合,具有良好的免疫反应性.     

H5N1型禽流感病毒HA基因在烟草中的表达

禽流感病毒H5N1是可以直接感染人类的甲型流感病毒，发展植物源口服疫苗是疫苗研究的方向之一．本研究通过农杆菌介导的方法将禽流感病毒H5N1的HA基因转化烟草．共获得38株潮霉素抗性植株，经PCR和Southern-blotting检测，目的基因已整合到转基因植株的基因组中．Western-dotting检测结果表明，目的基因在转基因烟草中得到表达，具有免疫原性，获得了能够表达HA基因的植物口服疫苗候选植株．     

Orisin and future distribution of the new A （H 1N1 ） influenza virus emerging in North America in 2009

The origin of the new A （H1N1） influenza virus recently emerging in North America is a hot controversial topic of significance in disease control and risk assessment. Some experts claimed that it was an unusually mongrelized mix of human, avian and swine influenza viruses, while some others concluded that it was totally a simple re-assortment hybrid of two lineages of swine influenza viruses. Here the phylogenetic diversity of the viral PB1, PA and PB2 gene sequences using online web servers, and the results suggest that all the 8 genetic segments of the new virus were possibly from two lineages of swine influenza viruses, and one of the lineage was a mongrelized mix of human, avian and swine influenza viruses emerging in the world approximately 10 years ago. Considering the recent epidemiological trends of the new virus, we believe it will spread more widely in the world and persist long in human populations. It also could spread among swine populations. The future wide spreading of the new virus may coincide the disappearance of a subtype of previous human influenza A virus.     

The mutation network for the hemagglutinin gene from the novel influenza A （H1N1 ） virus

A mutation network for the hemagglutinin gene （HA） of the novel type A （H1N1） influenza virus was constructed. Sequence homology analysis indicated that one HA sequence type from the viruses mainly isolated from Mexico was likely the original type in this epidemic. Based on the 658A and 1408T mutations in HA, the viruses evolving into this epidemic were divided into three categories, the Mexico, the transitional and the New York type. The three groups of viruses presented distinctive clustering features in their geographic distributions.     

禽流感病毒H5N1血凝素基因和神经氨酸酶基因在真核酵母菌中的表达

目的克隆、表达和鉴定禽流感病毒H5N1血凝素基因（hemagglutinin,HA）和神经氨酸酶基因（neuramidinase,NA）序列,为制备抗体和基因工程疫苗打下基础。方法在成功克隆禽流感病毒H5N1全长HA、NA基因并测序的基础上,将部分基因序列克隆到表达载体pMET A上,构建了重组表达质粒pMET A/HA（49～1 587 bp）、pMET A/NA（121～1 200 bp）,电转化真核酵母菌pMAD16,甲醇诱导表达,利用Ni2＋亲和层析柱对重组蛋白进行纯化,并用Western Blotting和ELISA方法检测其抗原性。结果重组蛋白在酵母菌中可以高效表达,SDS-PAGE显示蛋白表达后形成了二聚体,蛋白纯度占总蛋白的95%以上,ELISA和Western Blotting实验证实,重组蛋白具有良好的抗原性。结论本研究成功克隆和表达了禽流感病毒H5N1 HA、NA基因序列,为禽流感病毒H5N1诊断试剂和疫苗的开发等进一步的研究提供了依据。     

禽流感病毒HSNl血凝素基因和神经氨酸酶基因在真核酵母菌中的表达毒

目的克隆、表达和鉴定禽流感病毒HSNI血凝素基因(hemaggludnin,HA)和神经氨酸酶基因(neuramidinase,NA) 序列,为制备抗体和基因T程疫苗打下基础。方法在成功克隆禽流感病毒H5NI全长HA、NA基因并测序的基础 上。将部分基因序列克隆到表达载体pMET A上,构建了重组表达质粒pMET A／HA(49一l 587 bp)、pMET A／NA (121—1 200 bp),电转化真核酵母菌pMADl6,甲醇诱导表达,利用Ni“亲和层析柱对重组蛋白进行纯化,并用 Western Blotting和ELISA方法检测其抗原性。结果重组蛋白在酵母菌中可以高效表达,SDS—PAGE显示蛋白表 达后形成了二聚体,蛋白纯度占总蛋白的95％以上,ELISA和Western Blotting实验证实,重组蛋白具有良好的抗原 性。结论本研究成功克隆和表达了禽流感病毒H5NI HA、NA基因序列,为禽流感病毒H5N1诊断试剂和疫苗的 开发等进一步的研究提供了依据。     

Prediction of a common neutralizing epitope of H5N1 avian influenza virus by in silico molecular docking

The H5N1 avian influenza virus （AIV） has widely spread in Asia, Europe and Africa, making a large amount of economic loss. Recently, our research group has screened a common neutralizing mono-clonal antibody named 8H5, which can neutralize almost all H5 subtype AIV ever isolated so far. Obviously, this monoclonal antibody would benefit for research and development of the universal AIV vac-cine and design of the drug against H5N1 AIV in high mutation rate. In this study, the homology modeling was applied to generate the 3D structure of 8H5 Fab fragment, and ＂canonical structure＂ method was used to define the specified loop conformation of CDR regions. The model was subjected to energy minimization in cvff force field with Discovery module in Insight II program. The resulting model has correct stereochemistry as gauged from the Ramachandran plot calculation and good 3D-structure compatibility as assessed by interaction energy analysis, solvent accessible surface （SAS） analysis, and Profiles-3D approach. Furthermore, the 8H5 Fab model was subjected to docking with three H5 subtype hemagglutinin （HA） structures deposited in PDB （ID No： ljsm, 2ibx and 2fk0） respectively. The result indicates that the three docked complexes share a common binding interface, but differ in binding angle related with HA structure similarity between viral subtypes. In the light of the three HA inter-faces with structural homology analysis, the common neutralizing epitope on HA recognized by 8H5 consists of 9 incontinuous amino acid residues： Asp^58, Asn^72, Glu^112, Lys^113, lie^114, Pro^118, Ser^120, Tyr^137, Tyr^252 （numbered as for ljsm sequence）. The primary purpose of the present work is to provide some insight into structure and binding details of a common neutralizing epitope of H5N1 AIV, thereby aiding in the structure-based design of universal AIV vaccines and anti-virus therapeutic drugs.