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991.
The Douglas-fir tussock moth Orgyia pseudotsugata (Lepidoptera: Lymantriidae) is a frequent defoliator of Douglas-fir and true firs in western USA and Canada. A single nucleopolyhedrovirus (SNPV) isolated from O. pseudotsugata larvae in Canada (OpSNPV) was previously analyzed via its polyhedrin gene, but is phylogenetic status was ambiguous. Sequences of four conserved baculovirus genes, polyhedrin, lef-8, pif-2 and dpol, were amplified from OpSNPV DNA in polymerase chain reactions using degenerate primer sets and their sequences were analyzed phylogenetically. The analysis revealed that OpSNPV belongs to group Ⅱ NPVs and is most closely related to SNPVs that infect O. ericae and O. anartoides, respectively. These results show the need for multiple, concatenated gene phylogenies to classify baculoviruses.  相似文献   
992.
Guanylate binding protein-1(GBP-1)is an interferon-induced protein.To observe its antiviral effect against Hepatitis B virus(HBV)and Coxsackie virus B3(CVB3),we constructed an eukaryotic expression vector of human GBP-1(hGBP-1).Full-length encoding sequence of hGBP-1 was amplified by long chain RT-PCR and inserted into a pCR2.1 vector,then subcloned into a pCDNA3.1(-)vector.Recombinant hGBP-1 plasmids and pHBV1.3 carrying 1.3-fold genome of HBV were contransfected into HepG2 cells,and inhibition effect of hGBP-1 against HBV replication was observed.Hela cells transfected with recombinant hGBP-1 plasmids were challenged with CVB3,and viral yield in cultures were detected.The results indicated that recombinant eukaryotic expression plasmid of hGBP-1 was constructed successfully and the hGBP-1 gene carried in this plasmid could be efficiently expressed in HepG2 cells and Hela cells.hGBP-1 inhibit CVB3 but not HBV replication in vitro.These results demonstrate that hGBP-1 mediates an antiviral effect against CVB3 but not HBV and perhaps plays an important role in the interferon-mediated antiviral response against CVB3.  相似文献   
993.
HIV Vaccine-Challenges and Opportunities   总被引:1,自引:0,他引:1  
The need for an efficacious HIV/AIDS vaccine remains the highest priority of the world HIV/AIDS agenda. The generation of an efficacious HIV/AIDS vaccine proves an enormous scientific challenge. This article reviews the neutralizing antibody problem,elusive immune protection,im-munogen design,pre-existing anti-vector immunity and design of phase 3 vaccine trials and the challenges and opportunities in development of HIV/AIDS vaccine are discussed.  相似文献   
994.
By the end of 2005, the estimated number of HIV infected people in China was 650,000. The seriousness of the epidemic calls for effective control measures to tackle the problems in order to avoid the tragedy in Africa from happening in China. "Prevention First" is the cornerstone of the country's health policy. On 2003 World AIDS Day, Premier Jiabao Wen announced a new national AIDS control policy, "Four Frees and One Care". This policy clearly shows that the Chinese government has once again taken full responsibility to solve public health problems and has profound impact far beyond the AIDS field. In early 2006, the central government put scientific and technology innovation as a national priority and set the target to build an innovative China by year 2020. Since then, the government has been increasing investment in science and technology with major emphasis on both infectious diseases control and new drug research and development. For the first time, development of 100 new drugs and control of major infectious diseases (AIDS, HBV, TB and other emerging infectious diseases) have been selected as national key scientific projects. China's best minds in related fields will be pooled to work together in order to remove the technical barriers blocking efficient control of the major infectious disease in China. Knowledge on molecular epidemiology, immunology, pathogenesis, HAART, as well as HIVDR strains will certainly provide urgently needed scientific information for China's AIDS control program. Only evidence-based strategy from good research will provide long-term effective control of AIDS.  相似文献   
995.
The Asia-Pacific region is a home to 60% of the population in the world and to approximately one quarter of people with HIV/AIDS. Close to a million of people has been infected and a half million people died of AIDS annually in Asia,becoming the second largest epicenter of global AIDS epidemic. Molecular epidemiology has been useful tool to track a course of HIV spread. In-depth knowledge from the studies on molecular epidemiology elucidates the dynamics of HIV spread and the interrelationship of epidemics in the different regions in Asia.  相似文献   
996.
This paper describes the development and challenge of HIV/AIDS testing laboratory network and quality assurance system in China. At present,the HIV/AIDS testing laboratories includes three classes,the National AIDS Reference Laboratory,HIV/AIDS confirmatory laboratories and HIV/AIDS screening laboratories. All of them are accredited by the health authorities,and each class of laboratories take charge of their function strictly according to the "National Management of HIV/AIDS Detection (2006)". A complete quality assurance and quality control system for HIV/AIDS testing has been developed,which includes technical training,strict laboratory monitoring and approval,examination or proficiency testing on HIV/AIDS detection,and quality evaluation and supervision of HIV/AIDS diagnostic kits. Besides conduct the routine anti-HIV antibody test,more and more laboratories began to conduct other tests,such as CD4 T lymphocyte cell counting,HIV viral load,HIV DNA PCR,genotyping,drug resistance,and HIV-1 recent infection test. The primary challenges faced by the HIV/AIDS testing laboratory network are in the areas of laboratory management and quality control. For example,the provincial PT program is inefficient,the internal quality control is conducted perfunctorily,personnel training can not met the needs of the workplace,which need to be improved.  相似文献   
997.
Insect viruses are attractive as biological control agents and could be a feasible alternative to chemical insecticides in the management of insect infestations. This review describes recent advances in the development of wild-type and genetically modified viruses as insecticides. A new strategy of application of insect viruses in China is reviewed. Also, the assessment of biosafety of genetically modified Helicoverpa armigera Nucleopolyhedovirus (HearNPV) is emphasized as a case-study.  相似文献   
998.
Studies of the mechanism of HIV entry and transmission have identified multiple new targets for drug development. A range of inhibitors have demonstrated potent antiretroviral activity by interfering with CD4-gp120 interaction,coreceptor binding or viral-cell fusion in preclinical and clinical studies. One of these agents,fusion inhibitor enfuvirtide,is already in clinical use. Here we review the progress in the development of specific entry inhibitors as novel therapeutics. The potential of entry inhibitors as topical microbicides to block HIV transmission is also discussed.  相似文献   
999.
本文介绍国内外在利用植物病毒表达载体生产药物蛋白的研究现状,并对这一领域取得的最新突破进行重点阐述,包括Magnifection的原理、技术流程及利用其生产重组药用蛋白的优势、存在的问题等.最后,结合相关经验介绍利用植物病毒表达载体生产药物蛋白的应用前景及对该技术改进的建议.  相似文献   
1000.
Detection and Genetic Characterization of Rabies Virus from Human Patients   总被引:1,自引:0,他引:1  
Saliva and blood were collected from two patients who had not received post exposure prophylaxis in the cities of Wenzhou and Xinning respectively. Both patients were confirmed as positive for rabies by detection of rabies virus specific nucleoprotein antibodies in the sera by Western Blot. However, rabies virus specific RNA was only identified in the saliva collected from the patient in Wenzhou. Furthermore, the isolate Zhejiang Wz0 (H) was obtained by inoculating one-day-old suckling mice. Both nucleoprotein (N) and glycoprotein (G) genes from the isolate were amplified by RT-PCR and sequenced. Phylogenetic analysis indicated that the isolate belonged to classic rabies virus, and shared a higher homology with the street viruses from dogs in the main endemic areas in China and the street virus from dogs in Indonesia than with other known strains. Further comparison of the deduced amino acid sequences between the isolate and the vaccine strains used in China showed that the virus had a higher level of homology with the vaccine strain CTN than with the other vaccine strains (3aG, PV, PM and ERA). In particular, amino acid residues substitutions located in antigenic site Ⅲ in the G protein, which could react with the neutralizing antibodies, were observed. These results suggested that the virus belonged to the classic rabies virus, and both N and G genes diverged from the current vaccine strains used in China at either the nucleotide or the amino acid level.  相似文献   
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