WorldWideScience

Sample records for attenuated virus carrying

  1. Suppression of murine melanoma growth by a vaccine of attenuated Salmonella carrying heat shock protein 70 and Herpes simplex virus-thymidine kinase genes.

    Science.gov (United States)

    Zeng, Shuguang; Zhang, Jincai; Zhang, Jiren; Liu, Qicai; Wang, Suwen; Wu, Shiqing; Peng, Ximao; Shao, Jing; Huang, Wenge

    2012-03-01

    Attenuated Salmonella can invade tumor cells and acts as a eukaryotic expression vector for gene propagation. We constructed a bi-gene, eukaryotic co-expression DNA vaccine of Mycobacterium tuberculosis heat shock protein 70 (mtHSP70) and Herpes simplex virus-thymidine kinase (HSV-tk) and used attenuated Salmonella as a vector to treat murine melanoma. In vitro, recombinant Salmonella can carry plasmid stably and can invade into the cytoplasm of B16 tumor cells expressing the protein of the mtHSP70/HSV-tk gene by Western blot assay. In vivo, after the recombinant Salmonella was injected into tumors, the HSV-tk precursor drug ganciclovir (GCV) was administered to start the HSV-tk killing of tumor cells. We found that the mtHSP70/HSV-tk recombinant bacteria can raise CD8+ T lymphocytes in peripheral blood by flow cytometry and in tumor tissues by immunofluorescence detection, increase IFN‑γ contents in tumor tissue by ELISA and significantly suppress tumor growth.

  2. Molecular Characterization of Attenuated Junin Virus Variants.

    Science.gov (United States)

    1992-07-14

    No. DAMD17-89-Z-9024 Area de Quimica Biologica y Biologia Molecular Facultad de Ciencias Exactas Universidad Nacional de La Plata Calles 47 y 115, 1900...MONITORING ORGANIZATION Area de Quimica Biologica (If applicable) y Biologia Molecular I 6c. ADDRESS (City, State, and ZIPCode) 7b. ADDRESS (City, State...AD-A260 128 AD____ MOLECULAR CHARACTERIZATION OF ATTENUATED JUNIN VIRUS VARIANTS FINAL REPORT VICTOR ROMANOWSKI PABLO D. GHIRINGHELLI CESAR G

  3. Generation of influenza virus from avian cells infected by Salmonella carrying the viral genome.

    Directory of Open Access Journals (Sweden)

    Xiangmin Zhang

    Full Text Available Domestic poultry serve as intermediates for transmission of influenza A virus from the wild aquatic bird reservoir to humans, resulting in influenza outbreaks in poultry and potential epidemics/pandemics among human beings. To combat emerging avian influenza virus, an inexpensive, heat-stable, and orally administered influenza vaccine would be useful to vaccinate large commercial poultry flocks and even migratory birds. Our hypothesized vaccine is a recombinant attenuated bacterial strain able to mediate production of attenuated influenza virus in vivo to induce protective immunity against influenza. Here we report the feasibility and technical limitations toward such an ideal vaccine based on our exploratory study. Five 8-unit plasmids carrying a chloramphenicol resistance gene or free of an antibiotic resistance marker were constructed. Influenza virus was successfully generated in avian cells transfected by each of the plasmids. The Salmonella carrier was engineered to allow stable maintenance and conditional release of the 8-unit plasmid into the avian cells for recovery of influenza virus. Influenza A virus up to 10⁷ 50% tissue culture infective doses (TCID50/ml were recovered from 11 out of 26 co-cultures of chicken embryonic fibroblasts (CEF and Madin-Darby canine kidney (MDCK cells upon infection by the recombinant Salmonella carrying the 8-unit plasmid. Our data prove that a bacterial carrier can mediate generation of influenza virus by delivering its DNA cargoes into permissive host cells. Although we have made progress in developing this Salmonella influenza virus vaccine delivery system, further improvements are necessary to achieve efficient virus production, especially in vivo.

  4. Molecular basis of live-attenuated influenza virus.

    Directory of Open Access Journals (Sweden)

    Wen He

    Full Text Available Human influenza is a seasonal disease associated with significant morbidity and mortality. The most effective means for controlling infection and thereby reducing morbidity and mortality is vaccination with a three inactivated influenza virus strains mixture, or by intranasal administration of a group of three different live attenuated influenza vaccine strains. Comparing to the inactivated vaccine, the attenuated live viruses allow better elicitation of a long-lasting and broader immune (humoral and cellular response that represents a naturally occurring transient infection. The cold-adapted (ca influenza A/AA/6/60 (H2N2 (AA ca virus is the backbone for the live attenuated trivalent seasonal influenza vaccine licensed in the United States. Similarly, the influenza A components of live-attenuated vaccines used in Russia have been prepared as reassortants of the cold-adapted (ca H2N2 viruses, A/Leningrad/134/17/57-ca (Len/17 and A/Leningrad/134/47/57-ca (Len/47 along with virulent epidemic strains. However, the mechanism of temperature-sensitive attenuation is largely elusive. To understand how modification at genetic level of influenza virus would result in attenuation of human influenza virus A/PR/8/34 (H1N1,A/PR8, we investigated the involvement of key mutations in the PB1 and/or PB2 genes in attenuation of influenza virus in vitro and in vivo. We have demonstrated that a few of residues in PB1 and PB2 are critical for the phenotypes of live attenuated, temperature sensitive influenza viruses by minigenome assay and real-time PCR. The information of these mutation loci could be used for elucidation of mechanism of temperature-sensitive attenuation and as a new strategy for influenza vaccine development.

  5. Construction and characterization of recombinant Japanese encephalitis virus carrying brainspecific miRNA target sequences

    Directory of Open Access Journals (Sweden)

    Wen-yuan CAO

    2014-08-01

    Full Text Available Objective To construct the recombinant Japanese encephalitis virus ( JEV carrying brain-specific miRNA targeting sequences. Methods The target sequences of brain-specific miR-124 and miR-125 were introduced into the infectious cDNA clone of JEV to generate recombinant plasmids based on reverse genetics technology. The recombinant plasmids were linearized with Xho Ⅰ and served as templates of transcription with SP6 RNA polymerase to generate infectious viral RNA. The RNA transcripts were then transfected into BHK-21 cells, and the supernatant was obtained after incubated at 37℃, 5% CO2 for 3 days. The cytopathic changes of BHK-21 cells inoculated with the supernatant were observed after one passage. The rescued viruses carrying miRNA target sequences were validated by RT-PCR, standard plaque forming test on BHK-21 cells and growth curves analysis. Results Two recombinant viruses carrying miR-124 or miR-125 target sequence were rescued, respectively. The insertion of miRNA target sequences was confirmed by DNA sequencing. The rescued viruses yielded similar plaque morphology and replication efficiency compared with wild type JEV. Conclusion The recombinant JEV containing brain-specific miRNA target sequences can be obtained by reverse genetics technique, which could be used in further studies of miRNA-mediated tissue-specific attenuation mechanism of JEV. DOI: 10.11855/j.issn.0577-7402.2014.06.01

  6. Carry

    DEFF Research Database (Denmark)

    Koijen, Ralph S.J.; Moskowitz, Tobias J.; Heje Pedersen, Lasse;

    that include global equities, global bonds, currencies, commodities, US Treasuries, credit, and equity index options. This predictability underlies the strong returns to "carry trades" that go long high-carry and short low-carry securities, applied almost exclusively to currencies, but shown here...

  7. Wild type measles virus attenuation independent of type I IFN

    Directory of Open Access Journals (Sweden)

    Horvat Branka

    2008-02-01

    Full Text Available Abstract Background Measles virus attenuation has been historically performed by adaptation to cell culture. The current dogma is that attenuated virus strains induce more type I IFN and are more resistant to IFN-induced protection than wild type (wt. Results The adaptation of a measles virus isolate (G954-PBL by 13 passages in Vero cells induced a strong attenuation of this strain in vivo. The adapted virus (G954-V13 differs from its parental strain by only 5 amino acids (4 in P/V/C and 1 in the M gene. While a vaccine strain, Edmonston Zagreb, could replicate equally well in various primate cells, both G954 strains exhibited restriction to the specific cell type used initially for their propagation. Surprisingly, we observed that both G954 strains induced type I IFN, the wt strain inducing even more than the attenuated ones, particularly in human plasmacytoid Dendritic Cells. Type I IFN-induced protection from the infection of both G954 strains depended on the cell type analyzed, being less efficient in the cells used to grow the viral strain. Conclusion Thus, mutations in M and P/V/C proteins can critically affect MV pathogenicity, cellular tropism and lead to virus attenuation without interfering with the α/β IFN system.

  8. Intratumor injection of recombinant attenuated salmonella carrying Mycobacterium tuberculosis heat shock protein 70 and herpes simplex virus thymidine kinase genes to suppress murine melanoma growth%mtHSP70/HSV-tk重组沙门菌抗小鼠黑色素瘤的作用

    Institute of Scientific and Technical Information of China (English)

    曾曙光; 刘启才; 王素文; 彭细毛; 章锦才; 张积仁

    2012-01-01

    目的 研究携带结核杆菌热休克蛋白70(mtHSP70)、人单纯疱疹病毒一胸苷激酶(HSV-TK)双基因的重组沙门菌瘤内注射抗小鼠黑色素瘤的抑瘤效应.方法 构建重组沙门菌SL7207/PCMV-mtHSP70-IRES-TK,建立小鼠黑色素瘤动物模型,瘤内注射重组沙门菌观察其抑瘤效应、荷瘤鼠的生存期并进行安全性评估.结果 瘤内注射重组沙门菌,实验组抑瘤率显著高于对照组,延长荷瘤鼠生存期,重组菌治疗后荷瘤小鼠的生存状态良好,无腹泻,治疗期间体质量无明显改变.结论 减毒沙门菌携带的mtHSP70/HSV-TK双基因真核共表达质粒瘤内注射对B16肿瘤细胞具有显著抑制作用.%Objective To study the effection of suppression murine melanoma growth by Intratumor injection of recombinant attenuated salmonella carrying heat shock protein 70 and herpes simplex virus thymidine kinase genes. Methods Plasmids PCMV-mtHSP70-IRES-TK were electro-transferred into salmonella typhimurium SL7207 to construct recombinant salmonella typhimurium. In vivo, Recombinant bacteria were injected into the mouse melanoma and the antitumor effection was observed. The survival period was recorded and safety analysis for this vaccine in each group. Results In vivo, the mtHSP70/ HSV-tk recombinant bacteria can suppress tumor growth significantly and extend survival. After recombinant Salmonella, 10' CFU/mL, was administered as an intratumoral injection, No diarrhea were observed. During therapy, body weight did not change markedly. Conclusion Results of the animal experiment suggests intratumor injection of recombinant attenuated salmonella typhimurium containing mtHSP70 and HSV-tk genes, has targeting ability against B16 tumor cell and could significantly inhibit tumor growth.

  9. Mucosal vaccination with an attenuated maedi-visna virus clone.

    Science.gov (United States)

    Pétursson, Gudmundur; Matthíasdóttir, Sigrídur; Svansson, Vilhjálmur; Andrésdóttir, Valgerdur; Georgsson, Gudmundur; Martin, Agnes H; Agnarsdóttir, Gudrún; Gísladóttir, Eygló; Arnadóttir, Steinunn; Högnadóttir, Svava; Jónsson, Stefán Ragnar; Andrésson, Olafur S; Torsteinsdóttir, Sigurbjörg

    2005-05-02

    Four sheep were infected intratracheally with an attenuated molecular clone of maedi-visna virus (MVV). All four became infected. Ten months later these sheep were challenged intratracheally with a genetically similar but pathogenic clone of MVV. Four unvaccinated sheep were infected simultaneously. All sheep became infected by the challenge virus. The vaccinated sheep were not protected against superinfection with the challenge clone. However, virus was isolated more frequently from the blood of the unvaccinated controls than of the vaccinated animals and ten times more frequently from lungs of unvaccinated sheep than from lungs of vaccinated sheep at sacrifice, indicating partial protection.

  10. Construction of a recombinant attenuated Salmonella typhimurium DNA vaccine carrying Helicobacter pylori hpaA

    Institute of Scientific and Technical Information of China (English)

    Can Xu; Zhao-Shen Li; Yi-Qi Du; Zhen-Xing Tu; Yan-Fang Gong; Jing Jin; Hong-Yu Wu; Guo-Ming Xu

    2005-01-01

    AIM: To construct a recombinant attenuated Salmonella typhimurium DNA vaccine carrying Helicobacter pylori hpaA gene and to detect its immunogenicity.METHODS: Genomic DNA of the standard H pylori strain 17 874 was isolated as the template, hpaA gene fragment was amplified by polymerase chain reaction (PCR) and cloned into pUCmT vector. DNA sequence of the amplified hpaA gene was assayed, then cloned into the eukaryotic expression vector pIRES through enzyme digestion and ligation reactions. The recombinant plasmid was used to transform competent Escherichia coliDH5α, and the positive clones were screened by PCR and restriction enzyme digestion. Then, the recombinant pIRES-hpaA was used to transform LB5000 and the recombinant plasmid isolated from LB5000 was finally used to transform SL7207. After that, the recombinant strain was grown in vitrorepeatedly. In order to iclentify the immunogenicity of the vaccinein vitro, the recombinant pIRES-hpaA was transfected to COS-7 cells using LipofectamineTM2000, the immunogenicity of expressed HpaA protein was detected with SDS-PAGE and Western blot.RESULTS: The 750-base pair hpaA gene fragment was amplified from the genomic DNA and was consistent with the sequence of H pylori hpaA by sequence analysis. It was confirmed by PCR and restriction enzyme digestion that H pylori hpaA gene was inserted into the eukaryotic expression vector pIRES and a stable recombinant live attenuated Salmonella typhimurium DNA vaccine carrying H pylori hpaA gene was successfully constructed and the specific strip of HpaA expressed by pIRES-hpaA was detected through Western blot.CONCLUSION: The recombinant attenuated Salmonella typhimurium DNA vaccine strain expressing HpaA protein with immunogenicity can be constructed and it may be helpful for further investigating the immune action of DNA vaccine in vivo.

  11. Bats Found to Carry SARS-like Virus

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    @@ An international consortium headed by CAS researchers has identified that the Chinese horseshoe bat is healthy carriers of a virus that is very closely related to those causing SARS(severe acute respiratory syndrome). Their work was reported online on Sept. 29 by the Science magazine. The finding supports an independent study with similar results by Hong Kong scientists,which is reported by the Sept. 27issue of Proceedings of the National Academy of Sciences.

  12. Attenuated and vectored vaccines protect nonhuman primates against Chikungunya virus

    Science.gov (United States)

    Ljungberg, Karl; Kümmerer, Beate M.; Gosse, Leslie; Dereuddre-Bosquet, Nathalie; Tchitchek, Nicolas; Hallengärd, David; García-Arriaza, Juan; Meinke, Andreas; Esteban, Mariano; Merits, Andres

    2017-01-01

    Chikungunya virus (CHIKV) is rapidly spreading across the globe, and millions are infected. Morbidity due to this virus is a serious threat to public health, but at present, there is no vaccine against this debilitating disease. We have recently developed a number of vaccine candidates, and here we have evaluated 3 of them in a nonhuman primate model. A single immunization with an attenuated strain of CHIKV (Δ5nsP3), a homologous prime-boost immunization with a DNA-launched RNA replicon encoding CHIKV envelope proteins (DREP-E), and a DREP-E prime followed by a recombinant modified vaccinia virus Ankara encoding CHIKV capsid and envelope (MVA-CE) boost all induced protection against WT CHIKV infection. The attenuated Δ5nsP3 virus proved to be safe and did not show any clinical signs typically associated with WT CHIKV infections such as fever, skin rash, lymphopenia, or joint swelling. These vaccines are based on an East/Central/South African strain of Indian Ocean lineage, but they also generated neutralizing antibodies against an isolate of the Asian genotype that now is rapidly spreading across the Americas. These results form the basis for clinical development of an efficacious CHIKV vaccine that generates both humoral and cellular immunity with long-term immunological memory. PMID:28352649

  13. A replication-deficient rabies virus vaccine expressing Ebola virus glycoprotein is highly attenuated for neurovirulence

    Energy Technology Data Exchange (ETDEWEB)

    Papaneri, Amy B. [Emerging Viral Pathogens Section, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick, MD 21702 (United States); Wirblich, Christoph [Department of Microbiology and Immunology, Jefferson Medical College, Thomas Jefferson University, Philadelphia, PA 19107 (United States); Cann, Jennifer A.; Cooper, Kurt [Integrated Research Facility, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick MD, 21702 (United States); Jahrling, Peter B. [Emerging Viral Pathogens Section, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick, MD 21702 (United States); Integrated Research Facility, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick MD, 21702 (United States); Schnell, Matthias J., E-mail: matthias.schnell@jefferson.edu [Department of Microbiology and Immunology, Jefferson Medical College, Thomas Jefferson University, Philadelphia, PA 19107 (United States); Jefferson Vaccine Center, Jefferson Medical College, Thomas Jefferson University, Philadelphia, PA 19107 (United States); Blaney, Joseph E., E-mail: jblaney@niaid.nih.gov [Emerging Viral Pathogens Section, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick, MD 21702 (United States)

    2012-12-05

    We are developing inactivated and live-attenuated rabies virus (RABV) vaccines expressing Ebola virus (EBOV) glycoprotein for use in humans and endangered wildlife, respectively. Here, we further characterize the pathogenesis of the live-attenuated RABV/EBOV vaccine candidates in mice in an effort to define their growth properties and potential for safety. RABV vaccines expressing GP (RV-GP) or a replication-deficient derivative with a deletion of the RABV G gene (RV{Delta}G-GP) are both avirulent after intracerebral inoculation of adult mice. Furthermore, RV{Delta}G-GP is completely avirulent upon intracerebral inoculation of suckling mice unlike parental RABV vaccine or RV-GP. Analysis of RV{Delta}G-GP in the brain by quantitative PCR, determination of virus titer, and immunohistochemistry indicated greatly restricted virus replication. In summary, our findings indicate that RV-GP retains the attenuation phenotype of the live-attenuated RABV vaccine, and RV{Delta}G-GP would appear to be an even safer alternative for use in wildlife or consideration for human use.

  14. Evolutionary history and attenuation of myxoma virus on two continents.

    Science.gov (United States)

    Kerr, Peter J; Ghedin, Elodie; DePasse, Jay V; Fitch, Adam; Cattadori, Isabella M; Hudson, Peter J; Tscharke, David C; Read, Andrew F; Holmes, Edward C

    2012-01-01

    The attenuation of myxoma virus (MYXV) following its introduction as a biological control into the European rabbit populations of Australia and Europe is the canonical study of the evolution of virulence. However, the evolutionary genetics of this profound change in host-pathogen relationship is unknown. We describe the genome-scale evolution of MYXV covering a range of virulence grades sampled over 49 years from the parallel Australian and European epidemics, including the high-virulence progenitor strains released in the early 1950s. MYXV evolved rapidly over the sampling period, exhibiting one of the highest nucleotide substitution rates ever reported for a double-stranded DNA virus, and indicative of a relatively high mutation rate and/or a continually changing selective environment. Our comparative sequence data reveal that changes in virulence involved multiple genes, likely losses of gene function due to insertion-deletion events, and no mutations common to specific virulence grades. Hence, despite the similarity in selection pressures there are multiple genetic routes to attain either highly virulent or attenuated phenotypes in MYXV, resulting in convergence for phenotype but not genotype.

  15. Evolutionary history and attenuation of myxoma virus on two continents.

    Directory of Open Access Journals (Sweden)

    Peter J Kerr

    Full Text Available The attenuation of myxoma virus (MYXV following its introduction as a biological control into the European rabbit populations of Australia and Europe is the canonical study of the evolution of virulence. However, the evolutionary genetics of this profound change in host-pathogen relationship is unknown. We describe the genome-scale evolution of MYXV covering a range of virulence grades sampled over 49 years from the parallel Australian and European epidemics, including the high-virulence progenitor strains released in the early 1950s. MYXV evolved rapidly over the sampling period, exhibiting one of the highest nucleotide substitution rates ever reported for a double-stranded DNA virus, and indicative of a relatively high mutation rate and/or a continually changing selective environment. Our comparative sequence data reveal that changes in virulence involved multiple genes, likely losses of gene function due to insertion-deletion events, and no mutations common to specific virulence grades. Hence, despite the similarity in selection pressures there are multiple genetic routes to attain either highly virulent or attenuated phenotypes in MYXV, resulting in convergence for phenotype but not genotype.

  16. Live-attenuated measles virus vaccine targets dendritic cells and macrophages in muscle of nonhuman primates

    NARCIS (Netherlands)

    L.J. Rennick (Linda); R.D. de Vries (Rory); T.J. Carsillo (Thomas J.); K. Lemon (Ken); G. van Amerongen (Geert); M. Ludlow (Martin); D.T. Nguyen (Tien); S. Yüksel (Selma); R.J. Verbugh (Joyce); P. Haddock (Paula); S. McQuaid (Stephen); W.P. Duprex (Paul); R.L. de Swart (Rik)

    2015-01-01

    textabstractAlthough live-attenuated measles virus (MV) vaccines have been used successfully for over 50 years, the target cells that sustain virus replication in vivo are still unknown. We generated a reverse genetics system for the live-attenuated MV vaccine strain Edmonston- Zagreb (EZ), allowing

  17. No evidence of murine leukemia virus-related viruses in live attenuated human vaccines.

    Directory of Open Access Journals (Sweden)

    William M Switzer

    Full Text Available BACKGROUND: The association of xenotropic murine leukemia virus (MLV-related virus (XMRV in prostate cancer and chronic fatigue syndrome reported in previous studies remains controversial as these results have been questioned by recent data. Nonetheless, concerns have been raised regarding contamination of human vaccines as a possible source of introduction of XMRV and MLV into human populations. To address this possibility, we tested eight live attenuated human vaccines using generic PCR for XMRV and MLV sequences. Viral metagenomics using deep sequencing was also done to identify the possibility of other adventitious agents. RESULTS: All eight live attenuated vaccines, including Japanese encephalitis virus (JEV (SA-14-14-2, varicella (Varivax, measles, mumps, and rubella (MMR-II, measles (Attenuvax, rubella (Meruvax-II, rotavirus (Rotateq and Rotarix, and yellow fever virus were negative for XMRV and highly related MLV sequences. However, residual hamster DNA, but not RNA, containing novel endogenous gammaretrovirus sequences was detected in the JEV vaccine using PCR. Metagenomics analysis did not detect any adventitious viral sequences of public health concern. Intracisternal A particle sequences closest to those present in Syrian hamsters and not mice were also detected in the JEV SA-14-14-2 vaccine. Combined, these results are consistent with the production of the JEV vaccine in Syrian hamster cells. CONCLUSIONS: We found no evidence of XMRV and MLV in eight live attenuated human vaccines further supporting the safety of these vaccines. Our findings suggest that vaccines are an unlikely source of XMRV and MLV exposure in humans and are consistent with the mounting evidence on the absence of these viruses in humans.

  18. Congenital guinea pig infection with attenuated Junin virus strains.

    Science.gov (United States)

    Boxaca, M C; Gómez, M M; Malumbres, E; de Guerrero, L B

    1985-01-01

    Guinea pigs born from mothers infected before or during pregnancy with 10(3) PFU of the attenuated XJC13 or XJ0 strains of Junin virus (JV) by the intramuscular route showed 31.5% mortality that was not attributable to the mothers' clinical condition or to lack of care. There was a slight drop in mortality rate when the mothers were infected at the beginning or end of their gestation period. JV isolation from the 9 offspring killed from 1 to 125 days of age proved that virus transmitted transplacentally or soon after birth was able to persist, although titers were not higher than 10(2.7) PFU/g of tissue in various organs, including brain. Cell-associated viremia could thus account for viral spread after birth. Since an active humoral response was detected in the same animals, although Nt antibody titers were below 1:16, a state of tolerance did not exist in these congenitally infected animals. The carrier state appeared to modify guinea pig susceptibility to JV; after challenge with the pathogenic XJ strain of JV, 2 animals survived and developed normal humoral responses, while half of the remaining animals did not show typical signs of Argentine hemorrhagic fever. Although JV persistence appeared to cause no deleterious effects in surviving guinea pigs, its long-term risk remains to be determined.

  19. Uncovering the genetic basis of attenuation in Marek’s disease virus

    Science.gov (United States)

    While in vitro serial passage of Marek’s disease virus (MDV) is a proven method to attenuate MDV strains, the underlying genetic changes responsible for attenuation remains unknown. To identify candidate genes and mutations, a virulent MDV generated from an Md5-containing BAC clone was serially pass...

  20. Thogoto virus lacking interferon-antagonistic protein ML is strongly attenuated in newborn Mx1-positive but not Mx1-negative mice.

    Science.gov (United States)

    Pichlmair, Andreas; Buse, Johanna; Jennings, Stephanie; Haller, Otto; Kochs, Georg; Staeheli, Peter

    2004-10-01

    The Thogoto virus ML protein suppresses interferon synthesis in infected cells. Nevertheless, a virus mutant lacking ML remained highly pathogenic in standard laboratory mice. It was strongly attenuated, however, in mice carrying the interferon-responsive Mx1 gene found in wild mice, demonstrating that enhanced interferon synthesis is protective only if appropriate antiviral effector molecules are present. Our study shows that the virulence-enhancing effects of some viral interferon antagonists may escape detection in conventional animal models.

  1. CANINE DISTEMPER VIRUS ANTIBODY TITERS IN DOMESTIC CATS AFTER DELIVERY OF A LIVE ATTENUATED VIRUS VACCINE.

    Science.gov (United States)

    Ramsay, Edward; Sadler, Ryan; Rush, Robert; Seimon, Tracie; Tomaszewicz, Ania; Fleetwood, Ellen A; McAloose, Denise; Wilkes, Rebecca P

    2016-06-01

    Three methods for delivering a live attenuated canine distemper virus (CDV) vaccine to domestic cats ( Felis catus ) were investigated, as models for developing vaccination protocols for tigers (Panthera tigris). Twenty domestic cats were randomly divided into four treatment groups: saline injection (negative controls); and oral, intranasal, and subcutaneous vaccinates. Cats were injected with saline or a CDV vaccine (Nobivac DP, Merck) at wk 0 and 4. Blood and nasal swabs were collected at wk 0 (prior to the initial vaccination) and weekly thereafter for 9 wk. Urine samples were collected on wk 1 to 9 after initial vaccination. Forty-nine weeks following the initial vaccination series, three cats from the subcutaneous group and three cats from the intranasal group were revaccinated. Blood was collected immediately prior, and 7 and 21 days subsequent to revaccination. Nasal swabs and urine samples were collected from each cat prior to wk 49 revaccination and daily for 7 days thereafter. Nasal swabs and urine were analyzed by quantitative PCR for vaccine virus presence. Sera were tested for CDV antibodies by virus neutralization. All cats were sero-negative for CDV antibodies at the beginning of the study, and saline-injected cats remained sero-negative throughout the study. A dramatic anamnestic response was seen following wk 4 subcutaneous vaccinations, with titers peaking at wk 6 (geometric mean = 2,435.5). Following wk 49 revaccination, subcutaneous vaccinates again mounted impressive titers (wk 52 geometric mean = 2,048). Revaccination of the intranasal group cats at wk 49 produced a small increase in titers (wk 52 geometric mean = 203). CDV viral RNA was detected in six nasal swabs but no urine samples, demonstrating low viral shedding postvaccination. The strong antibody response to subcutaneous vaccination and the lack of adverse effects suggest this vaccine is safe and potentially protective against CDV infection in domestic cats.

  2. Comparison of Thinopyrum intermedium derivatives carrying barley yellow dwarf virus resistance in wheat.

    Science.gov (United States)

    Ayala-Navarrete, L; Tourton, E; Mechanicos, A A; Larkin, P J

    2009-06-01

    Resistance to both barley yellow dwarf virus (BYDV) and cereal yellow dwarf virus (CYDV) has been demonstrated in wheat genetic stocks with Thinopyrum intermedium chromatin. A number of resistance-bearing translocations have been reported on chromosome arm 7DL from two independent Th. intermedium sources; one source is the addition line L1 and the other is the spontaneous substitution line P29. Another source of resistance in wheat cytogenetic stocks is available as a 2Ai(2D) substitution line. We used a set of 38 molecular markers and the available deletion stocks to compare the size of the 7DL translocations more comprehensively than has been done previously. We also compared the efficacy of BYDV resistance of the various genetic stocks both before and after transfer to a common genetic background. TC14 was confirmed as carrying the smallest translocation, replacing about 20% of the distal end of 7DL. TC5 and TC10 had 90% of the chromosome arm replaced by Th. intermedium chromatin; the proximal 10% corresponded to wheat chromatin. YW642 appeared to have the whole 7DL replaced by Th. intermedium chromatin, as confirmed by the co-dominant marker cfd68 mapping on the bin nearest the centromere. Translocation line P961341 had bins 3, 7, and 8 replaced by Th. intermedium chromatin, making this the second smallest translocation with BYDV and CYDV resistance. The translocation sizes reported here differ from some of the previous estimates. The translocated Th. intermedium segments appeared to be bigger than the replaced wheat 7DL fragments. All the resistances derived from the L1 and P29 group 7 chromosomes and the 2Ai#2 chromosome were effective in reducing the number of infected plants and the mean virus titre, regardless of the background. Some evidence is discussed suggesting the long arm of the Th. intermedium group 7 chromosome 7Ai#1 carries two resistances, the distal Bdv2 and a proximal second gene.

  3. Herpes simplex virus type-1(HSV-1 oncolytic and highly fusogenic mutants carrying the NV1020 genomic deletion effectively inhibit primary and metastatic tumors in mice

    Directory of Open Access Journals (Sweden)

    David Andrew T

    2008-06-01

    Full Text Available Abstract Background The NV1020 oncolytic herpes simplex virus type-1 has shown significant promise for the treatment of many different types of tumors in experimental animal models and human trials. Previously, we described the construction and use of the NV1020-like virus OncSyn to treat human breast tumors implanted in nude mice. The syncytial mutation gKsyn1 (Ala-to-Val at position 40 was introduced into the OncSyn viral genome cloned into a bacterial artificial chromosome using double-red mutagenesis in E. coli to produce the OncdSyn virus carrying syncytial mutations in both gB(syn3 and gK(syn1. Results The OncdSyn virus caused extensive virus-induced cell fusion in cell culture. The oncolytic potential of the OncSyn and OncdSyn viruses was tested in the highly metastatic syngeneic mouse model system, which utilizes 4T1 murine mammary cancer cells implanted within the interscapular region of Balb/c mice. Mice were given three consecutive intratumor injections of OncSyn, OncdSyn, or phosphate buffered saline four days apart. Both OncSyn and OncdSyn virus injections resulted in significant reduction of tumor sizes (p Conclusion These results show that the attenuated, but highly fusogenic OncSyn and OncdSyn viruses can effectively reduce primary and metastatic breast tumors in immuncompetent mice. The available bac-cloned OncSyn and OncdSyn viral genomes can be rapidly modified to express a number of different anti-tumor and immunomodulatory genes that can further enhance their anti-tumor potency.

  4. Microarray-Based Detection and Differentiation of Virulent and Attenuated Pseudorabies Virus

    Institute of Scientific and Technical Information of China (English)

    LIU Li-na; LIU Zheng-fei; RUAN Li; WANG Zhao-xiong; LI Ren-feng; ZHANG Song-lin; CHEN Huan-chun; HE Qi-gai

    2007-01-01

    DNA microchip used in this study was formed from miniature arrays of pseudorabies virus (PrV) gene-specific probes immobilized on a glass surface. Hybridization using DNA microchip (microarrays) was used for differentiation between virulent and attenuated PrV. The presence of four gene segments (gB, gD, gE+, and gE- ) encoding conservative glycoprotein B (gB), D (gD), and E (gE) of PrV was monitored using multiplex PCR. The amplicons were labeled with Cy5 or Cy3 dyes followed by hybridization to the gene-specific capture probes on the microchip. The presence of gD and gB, gE+ gene fragments was shown in virulent (gE+ genotype) and attenuated PrV (gE genotype), whereas gE- gene (deleted domain in gE gene) was demonstrated only in virulent, not in attenuated, virus. No cross-hybridization was observed when fluorescence labeled-PCR products of PrV were hybridized using capture probes of related viruses, such as porcine respiratory and reproductive syndrome virus (PRRSV), porcine parvovirus (PPV), Japanese encephalitis virus (JEV), and porcine circovirus type 2 (PCV-2). The assay was 10 times sensitive than gD gene-specific PCR. Overall, the results of this study suggested that the microarray might be very useful for detection and differentiation of virulent PrV from attenuated one.

  5. Plasmid-based Survivin shRNA and GRIM-19 carried by attenuated Salmonella suppresses tumor cell growth

    Institute of Scientific and Technical Information of China (English)

    Yan-Bo Liu1; De-Qi Xu; Ling Zhang1; Ya-Xiong Guo; Li-Fang Gao; Xi-Chun Liu; Li-Juan Zhao; Bao-Feng Guo; Li-Jing Zhao; Xue-Jian Zhao

    2012-01-01

    Persistent activation of Survivin and its overexpression contribute to the formation,progression and metastasis of several different tumor types.Therefore,Survivin is an ideal target for RNA interference mediated-growth inhibition.Blockade of Survivin using specific short hairpin RNAs (shRNA) can significantly reduce prostate tumor growth.RNA interference does not fully ablate target gene expression,owing to the idiosyncrasies associated with shRNAs and their targets.To enhance the therapeutic efficacy of Survivin-specific shRNA,we employed a combinatorial expression of Survivin-specific shRNA and gene associated with retinoid-interferon-induced mortality-19 (GRIM-19).Then,the GRIM-19 coding sequences and Survivin-specific shRNAs were used to create a dual expression plasmid vector and were carried by an attenuated strain of Salmonella enteric serovar typhimurium (S.typhimurium) to treat prostate cancer in vitroand in vivo.We found that the co-expressed Survivin-specific shRNA and GRIM-19synergistically and more effectively inhibited prostate tumor proliferation and survival,when compared with treatment with either single agent alone in vitro and in vivo.This study has provided a novel cancer gene therapeutic approach for prostate cancer.

  6. Studies on the phenotypic and genotypic characteristics of SA14 wild Japanese encephalitis virus and its attenuated viruses

    Institute of Scientific and Technical Information of China (English)

    XING LIANG FAN; YONG XIN YU; DE FU LI; ZHI HUI YAO; LI LI JIA

    2006-01-01

    The aim of this study was to explore the molecular basis for the attenuation of the Japanese encephalitis virus (JEV) vaccine strain SA14-14-2. The virulence of SA14 wild Japanese encephalitis virus (JEV) and its several attenuated viruses was tested by intracerebral (i. c. ) or intraperitonial (i. p. ) inoculation of 10-12 g mice. The stability of neuroattenuation was tested by one passage in suckling mouse brain. The E protein genes of those viruses were amplified by PCR, sequenced and compared. Three attenuated virus strains, SA14-14-2 vaccine virus, SA14-9-7 and SA14-5-3, did not exhibit lethal infections by i.c. or i.p. inoculation of 10-12 g mice and revert to the virulence. The other virus strain, SA14-12-1-7, showed no neuroinvasiveness by i.p. inoculation but residual neurovirulence by i.c. inoculation and reverted to high virulence after one brain passage. Comparison of the E protein gene sequences of the five virus strains indicated that there were differences of twelve nucleotides and eight amino acids between the parent strain SA14 and vaccine strain SA14-14-2, of which six amino acids (E-107, E-176, E-439, E138, E-279, E-315) exhibited changes common to those of SA14-9-7 and SA14-5-3, three substitutions common to SA14-12-1-7. Two amino acid substitutions at the sites E177 (T→A) and E264 (Q→H) are unique to the SA14-14-2 vaccine virus. The results suggest that the mutations of E-107 (Leu→Phe), E176 (Ile→Val), and E-439 (Lys→Arg) may contribute for the attenuation of neuroinvasiveness and partially for the attenuation of neurovirulence, the mutations of E-138, E-279, E-315 may not only critical to the neuroattenuation but also to its stability.

  7. An Overview of Live Attenuated Recombinant Pseudorabies Viruses for Use as Novel Vaccines

    Directory of Open Access Journals (Sweden)

    Bo Dong

    2014-01-01

    Full Text Available Pseudorabies virus (PRV is a double-stranded, DNA-based swine virus with a genome approximating 150 kb in size. PRV has many nonessential genes which can be replaced with genes encoding heterologous antigens but without deleterious effects on virus propagation. Recombinant PRVs expressing both native and foreign antigens are able to stimulate immune responses. In this paper, we review the current status of live attenuated recombinant PRVs and live PRV-based vector vaccines with potential for controlling viral infections in animals.

  8. Rapid strategy for screening by pyrosequencing of influenza virus reassortants--candidates for live attenuated vaccines.

    Directory of Open Access Journals (Sweden)

    Svetlana V Shcherbik

    Full Text Available BACKGROUND: Live attenuated influenza vaccine viruses (LAIVs can be generated by classical reassortment of gene segments between a cold adapted, temperature sensitive and attenuated Master Donor Virus (MDV and a seasonal wild-type (wt virus. The vaccine candidates contain hemagglutinin (HA and neuraminidase (NA genes derived from the circulating wt viruses and the remaining six genes derived from the MDV strains. Rapid, efficient selection of the viruses with 6∶2 genome compositions from the large number of genetically different viruses generated during reassortment is essential for the biannual production schedule of vaccine viruses. METHODOLOGY/PRINCIPAL FINDINGS: This manuscript describes a new approach for the genotypic analysis of LAIV reassortant virus clones based on pyrosequencing. LAIV candidate viruses were created by classical reassortment of seasonal influenza A (H3N2 (A/Victoria/361/2011, A/Ohio/02/2012, A/Texas/50/2012 or influenza A (H7N9 (A/Anhui/1/2013 wt viruses with the MDV A/Leningrad/134/17/57(H2N2. Using strain-specific pyrosequencing assays, mixed gene variations were detected in the allantoic progenies during the cloning procedure. The pyrosequencing analysis also allowed for estimation of the relative abundance of segment variants in mixed populations. This semi-quantitative approach was used for selecting specific clones for the subsequent cloning procedures. CONCLUSIONS/SIGNIFICANCE: The present study demonstrates that pyrosequencing analysis is a useful technique for rapid and reliable genotyping of reassortants and intermediate clones during the preparation of LAIV candidates, and can expedite the selection of vaccine virus candidates.

  9. Antibody Response in Seropositive Multiple Sclerosis Patients Vaccinated with Attenuated Live Varicella Zoster Virus

    Directory of Open Access Journals (Sweden)

    RT Ross

    1996-01-01

    Full Text Available OBJECTIVE: To determine the safety and effectiveness of live attenuated varicella zoster virus (VZV vaccine (OKA/Merck on 50 patients with chronic progressive multiple sclerosis (MS, based on the hypothesis that VZV might be the antigen or antigen mimic of MS plus the fact that repeated high antigen doses have produced ‘antigen paralysis’ in experimental allergic encephalomyelitis mice.

  10. Soil-borne wheat mosaic virus infectious clone and manipulation for gene-carrying capacity

    Science.gov (United States)

    Soilborne wheat mosaic virus (SBWMV) is a bipartite single stranded positive sense RNA virus with rigid-rod shaped virions. Taxonomically the virus is in the family Viragviridae, as are commonly used gene silencing or expression viral vectors, Tobacco rattle virus (TRV) and Barley stripe mosaic viru...

  11. Effects of mutated replicase and movement protein genes on attenuation of tobacco mosaic virus

    Institute of Scientific and Technical Information of China (English)

    杨恭; 邱并生; 魏军亚; 刘广超

    2001-01-01

    Our previous reports showed that one opal mutation (UGA) and one ochre mutation (UAA) respectively located in the replicase and movement protein (MP) genes of the attenuated tomato mosaic virus K(ToMV-K) contribute to the viral attenuation. To explore a wider application of this attenuation pattern to other plant viruses, we have constructed three mutants which respectively contain one opal mutation of the replicase gene and/or one ochre mutation of the MP using PCR-mediated site-directed mutagenesis from a virulent tobacco mosaic virus isolated from China (TMV-Cv). Plant infection performed by in vitro transcripts revealed that the MP truncated mutant TMV-Cvmp and the replicase-MP truncated mutant TMV-Cvrase-mp were infectious on both local lesion (Nicotiana tabacum cv. Xanthi NC) and systemic (N. tabacum cv. K326) host plants, while the replicase truncated mutant TMV-Cvrase was non-infectious. The K326 plant infected by TMV- Cvrease-mp displayed only a little mild mosaic. By electronic microscopy (EM), plant re-inoculation, RNA Dot-blot, RT-PCR and sequencing we demonstrated that the progeny viruses of TMV-Cvmp and TMV-Cvrease-mp shared similar morphological character with TMV-Cv, owned the abilities to infect, replicate and propagate in the assayed plants, and maintained the mutated sites during infection. These data showed that both the opal and the ochre mutations are able to cooperatively induce the attenuated phenotypes of TMV-Cvrase-mp on plants, indicating that the mutation pattern of ToMV-K could be used to attenuate other virulent plant viruses.

  12. RNA virus attenuation by codon pair deoptimisation is an artefact of increases in CpG/UpA dinucleotide frequencies.

    Science.gov (United States)

    Tulloch, Fiona; Atkinson, Nicky J; Evans, David J; Ryan, Martin D; Simmonds, Peter

    2014-12-09

    Mutating RNA virus genomes to alter codon pair (CP) frequencies and reduce translation efficiency has been advocated as a method to generate safe, attenuated virus vaccines. However, selection for disfavoured CPs leads to unintended increases in CpG and UpA dinucleotide frequencies that also attenuate replication. We designed and phenotypically characterised mutants of the picornavirus, echovirus 7, in which these parameters were independently varied to determine which most influenced virus replication. CpG and UpA dinucleotide frequencies primarily influenced virus replication ability while no fitness differences were observed between mutants with different CP usage where dinucleotide frequencies were kept constant. Contrastingly, translation efficiency was unaffected by either CP usage or dinucleotide frequencies. This mechanistic insight is critical for future rational design of live virus vaccines and their safety evaluation; attenuation is mediated through enhanced innate immune responses to viruses with elevated CpG/UpA dinucleotide frequencies rather the viruses themselves being intrinsically defective.

  13. The replication of Bangladeshi H9N2 avian influenza viruses carrying genes from H7N3 in mammals.

    Science.gov (United States)

    Shanmuganatham, Karthik K; Jones, Jeremy C; Marathe, Bindumadhav M; Feeroz, Mohammed M; Jones-Engel, Lisa; Walker, David; Turner, Jasmine; Rabiul Alam, S M; Kamrul Hasan, M; Akhtar, Sharmin; Seiler, Patrick; McKenzie, Pamela; Krauss, Scott; Webby, Richard J; Webster, Robert G

    2016-04-20

    H9N2 avian influenza viruses are continuously monitored by the World Health Organization because they are endemic; they continually reassort with H5N1, H7N9 and H10N8 viruses; and they periodically cause human infections. We characterized H9N2 influenza viruses carrying internal genes from highly pathogenic H7N3 viruses, which were isolated from chickens or quail from live-bird markets in Bangladesh between 2010 and 2013. All of the H9N2 viruses used in this study carried mammalian host-specific mutations. We studied their replication kinetics in normal human bronchoepithelial cells and swine tracheal and lung explants, which exhibit many features of the mammalian airway epithelium and serve as a mammalian host model. All H9N2 viruses replicated to moderate-to-high titers in the normal human bronchoepithelial cells and swine lung explants, but replication was limited in the swine tracheal explants. In Balb/c mice, the H9N2 viruses were nonlethal, replicated to moderately high titers and the infection was confined to the lungs. In the ferret model of human influenza infection and transmission, H9N2 viruses possessing the Q226L substitution in hemagglutinin replicated well without clinical signs and spread via direct contact but not by aerosol. None of the H9N2 viruses tested were resistant to the neuraminidase inhibitors. Our study shows that the Bangladeshi H9N2 viruses have the potential to infect humans and highlights the importance of monitoring and characterizing this influenza subtype to better understand the potential risk these viruses pose to humans.

  14. Effects of mutated replicase and movement protein genes on attenuation of tobacco mosaic virus

    Institute of Scientific and Technical Information of China (English)

    YANG; Gong; (

    2001-01-01

    [1]Banerjee, N., Wang, J. Y., Zaitlin, M., A single nucleotide change in the coat protein gene of tobacco mosaic virus is involved in the induction of severe chlorosis, Virology, 1995, 207: 234-239.[2]Dawson, W. O., Bubrick, P., Grantham, G. L., Modifications of the tobacco mosaic virus coat protein gene affecting replication, movement, and symptomatology, Mol. Plant Pathol., 1988, 78: 783-789.[3]Lu, B., Stubbs, G., Culver, J. N., Coat protein interactions involved in tobacco mosaic tobamovirus cross-protection, Virology, 1998, 248: 188-198.[4]Bao, Y. M., Carter, S. A., Nelson,R. S., The 126- and 183-kilodalton proteins of tobacco mosaic virus, and not their common nucleotide sequence, control mosaic symptom formation in tobacco, J. Virol., 1996, 70: 6378-6383.[5]Holt, C. A., Hodgson, A. J., Coker, F. A. et al., Characterization of the masked strain of tobacco mosaic virus: identification of the region responsible for symptom attenuation by analysis of an infectious cDNA clone, Mol. Plant-Microbe Interact., 1990, 3: 417-423.[6]Nishiguchi, M., Kikuchi, S., Kiho, Y. et al., Molecular basis of plant viral virulence, the complete nucleotide sequence of an attenuated strain of tobacco mosaic virus, Nucleic Acids Res., 1985, 13: 5585-5590.[7]Watanabe, Y., Morita, N., Nishiguchi, M.et al., Attenuated strains of tobacco mosaic virus reduced synthesis of a viral protein with a cell to cell movement function, J. Mol. Biol., 1987, 194: 699-704.[8]Lewandowski, D. J., Dawson, W. O., A single amino acid change in tobacco mosaic virus replicase prevents symptom production, Mol. Plant-Microbe Interact., 1993, 6: 157-160.[9]Yang, G., Qiu, B. S., Cloning and infectivity analysis of the cDNAs of tobacco mosaic virus (tomato strain) and its attenuated virus (N14) genomes, Chinese Journal of Biotechnology (in Chinese), 2000, 16: 207-210.[10]Yang, G., Liu, X. G., Qiu, B. S., Complete nucleotid sequences and genome structures of two Chinese tobacco

  15. Cellular and Biochemical Changes of Antheraea mylitta D. on Immunization with Attenuated Antheraea mylitta Cytoplasmic Polyhedrosis Virus

    Directory of Open Access Journals (Sweden)

    Phani Kiran Kumar

    2011-01-01

    Full Text Available The aim of the present study is to analyze the cellular and biochemical changes noticed in tasar silkworm larva (Antheraea mylitta D. immunized with attenuated cytoplasmic polyhedrosis virus (AmCPV. The bioassay was carried out to confirm the no induction of disease in attenuated AmCPV inoculated larvae. Total Haemocytes count and Differential Haemocytes counts were carried out in healthy control, immunized and non immunized silkworm larvae at different time intervals. The hemolymph proteins were estimated in healthy control, immunized and non immunized silkworm larvae. The results confirm that, attenuated AmCPV provides protection against AmCPV infection for a short period (6 to 8 days. The mortality in immunized silkworms was reduced significantly as compared to non immunized inoculated control. The total haemocyte counts increased in haemolymph up to 8th day in immunized silkworms in comparison with non immunized inoculated control indicating the positive haemocyte mediated response in silkworm immunized with attenuated AmCPV. Similarly, differential haemocyte count was different in immunized silkworms from the inoculated control. The prohaemocyte, plasmatocytes and granulocytes were maximum in number whereas oenocytoids were minimum in number. The number of degenerated blood cells was increased in inoculated control up to 8th days of post inoculation. The hemolymph protein in immunized silkworms was significantly higher than non immunized control. The gradual increase 1st day to 8th day was observed in immunized silkworm. In non immunized inoculated control, the total hemolymph proteins have shown increasing trend from 1st to 5th day and decreasing from 6th day onwards.

  16. Protection by attenuated and polyvalent vaccines against highly virulent strains of Marek's disease virus.

    Science.gov (United States)

    Witter, R L

    1982-01-01

    Tests confirmed that turkey herpesvirus (HVT) vaccine protected chickens poorly against challenge with the highly virulent Md5 strain of Marek's disease (MD) virus, especially in chickens with homologous HVT antibodies. The naturally avirulent SB-1 vaccine virus was likewise poorly protective against challenge with the Md5 strain. Homologous antibodies reduced the protective efficacy of both vaccines, but SB-1 was not affected by HVT antibodies. In order to provide better protection against strains of MD virus poorly protected against by HVT, such as Md5, the Md11 strain of MD virus was attenuated by 75 cell culture passages and evaluated for protective efficacy. This vaccine virus, designated Mdl 1/75C, provided good protection against challenge with Md5 and most other highly virulent MD viruses tested, but was less efficacious against challenge with the JM/102W strain, a prototype MD virus protected against well by HVT and SB-1 vaccines. Furthermore, its efficacy was consistently lower in chicks with HVT antibody. Thus, although HVT, SB-1, and Md11/75C were all efficacious against certain MD viruses, none of these vaccines protected optimally against all MD challenge viruses in all chickens. A polyvalent vaccine composed of Md11/75C, HVT and SB-1 viruses protected chickens better against a battery of five highly virulent MD challenge viruses, including three strains poorly protected against by HVT, than any single vaccine and was not influenced by HVT antibody. These data suggest that vaccinal immunity may be partially viral strain specific.

  17. In Vitro and In Vivo Attenuation of Vesicular Stomatitis Virus (VSV by Phosphoprotein Deletion.

    Directory of Open Access Journals (Sweden)

    Phonphimon Wongthida

    Full Text Available Vesicular stomatitis virus (VSV is highly immunogenic and able to stimulate both innate and adaptive immune responses. However, its ability to induce adverse effects has held back the use of VSV as a potential vaccine vector. In this study we developed VSV-ΔP, a safe yet potent replication-defective recombinant VSV in which the phosphoprotein (P gene was deleted. VSV-ΔP replicated only in supporting cells expressing P (BHK-P cells and at levels more than 2 logs lower than VSV. In vivo studies indicated that the moderate replication of VSV-ΔP in vitro was associated with the attenuation of this virus in the mouse model, whereas mice intracranially injected with VSV succumbed to neurotoxicity. Furthermore, we constructed VSV and VSV-ΔP expressing a variety of antigens including hemagglutinin-neuraminidase (HN from Newcastle disease virus (NDV, hemagglutinin (HA from either a 2009 H1N1 pandemic influenza virus (pdm/09 or the avian H7N9. VSV and VSV-ΔP incorporated the foreign antigens on their surface resulting in induction of robust neutralizing antibody, serum IgG, and hemagglutination inhibition (HAI titers against their corresponding viruses. These results indicated that VSV with P gene deletion was attenuated in vitro and in vivo, and possibly expressed the foreign antigen on its surface. Therefore, the P gene-deletion strategy may offer a potentially useful and safer approach for attenuating negative-sense RNA viruses which use phosphoprotein as a cofactor for viral replication.

  18. Quantitative polymerase chain reaction: another tool to evaluate viable virus content in live attenuated orf vaccine

    Directory of Open Access Journals (Sweden)

    Durlav Prasad Bora

    2012-12-01

    Full Text Available A probe-based real-time polymerase chain reaction (PCR assay based on the highly conserved DNA polymerase gene of orf virus (ORFV for the quality control of attenuated orf vaccine is reported. Primary lamb testis (PLT cells were infected with orf vaccine virus and harvested at a critical time point to obtain maximum viable virus content as determined by real-time PCR. DNA extracted from these harvests was subjected to real-time PCR. A critical time point for the harvesting of PLT cells infected with various log10 dilutions of vaccine virus was found to be 42 h (highest slope of 3.335, which was obtained by comparing the slopes of standard curves of different time intervals. The assay was employed to evaluate viable virus content in different batches of orf vaccine. The titres estimated by real-time PCR and conventional TCID50 were comparable with a correlation of 0.8169. Thus, the real-time PCR assay could provide an alternative method or supplementary tool to estimate live ORFV particles in attenuated orf vaccine.

  19. Pathogenicity and Immunogenicity of a Mutagen-Attenuated Rift Valley Fever Virus Immunogen in Pregnant Ewes

    Science.gov (United States)

    1987-07-01

    RVFV antibody titers of < 1:10 at birth, increasing to > animals to produce attenuated virus vaccines."’ Prop- 1:80 after ingestion of colostrum ...immunogenicity of the mutagenized ZH- Culex pipiens that fed on the MV P12-inoculated ewes 548 strain RVFV (MV P12) in pregnant sheep and to as- failed to...reduction neutralization assay. viral disease of sheep , cattle, and goats.’ 2 Infected ani- mals develop high viremia titers, virtually all pregnant

  20. Identification of ALV-J associated acutely transforming virus Fu-J carrying complete v-fps oncogene.

    Science.gov (United States)

    Wang, Yixin; Li, Jianliang; Li, Yang; Fang, Lichun; Sun, Xiaolong; Chang, Shuang; Zhao, Peng; Cui, Zhizhong

    2016-06-01

    Transduction of oncogenes by ALVs and generation of acute transforming viruses is common in natural viral infections. In order to understand the molecular basis for the rapid oncogenicity of Fu-J, an acutely transforming avian leukosis virus isolated from fibrosarcomas in crossbreed broilers infected with subgroup J avian leukosis virus (ALV-J) in China, complete genomic structure of Fu-J virus was determined by PCR amplification and compared with those of Fu-J1, Fu-J2, Fu-J3, Fu-J4, and Fu-J5 reported previously. The results showed that the genome of Fu-J was defective, with parts of gag gene replaced by the complete v-fps oncogene and encoded a 137 kDa Gag-fps fusion protein. Sequence analysis revealed that Fu-J and Fu-J1 to Fu-J5 were related quasi-species variants carrying different lengths of v-fps oncogenes generated from recombination between helper virus and c-fps gene. Comparison of virus carrying v-fps oncogene also gave us a glimpse of the molecular characterization and evolution process of the acutely transforming ALV.

  1. Prophylaxis of tumor through oral administration of IL-12 GM-CSF gene carried by live attenuated salmonella

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A live attenuated AraA- autotrophic mutant of Salmonella typhimurium (SL3261) was used as carrier for eukaryotic expression vectors EGFPN1, pCMVmIL-12, pCMVhIL-12, pCMVmGM-CSF and pCMVhGM-CSF and was administered orally to BALB/c and C57BL/6 mice. After 6 weeks, these mice were challenged with 4T1 and Lewis tumor cells respectively. GFP expression and gene integrati-on could be detected in mice's livers, spleens, intestines, kidneys and tumors. The serum level of cytokines increased significantly in treated mice, so did the ratio of , which resulted in the tumor regression and prolongation of the survival time of those mice. These researches laid an experimental foundation for the tumor gene therapy using live attenuated salmonella.

  2. Attenuation and immunogenicity of recombinant yellow fever 17D-dengue type 2 virus for rhesus monkeys

    Directory of Open Access Journals (Sweden)

    Galler R.

    2005-01-01

    Full Text Available A chimeric yellow fever (YF-dengue serotype 2 (dengue 2 virus was constructed by replacing the premembrane and envelope genes of the YF 17D virus with those from dengue 2 virus strains of Southeast Asian genotype. The virus grew to high titers in Vero cells and, after passage 2, was used for immunogenicity and attenuation studies in rhesus monkeys. Subcutaneous immunization of naive rhesus monkeys with the 17D-D2 chimeric virus induced a neutralizing antibody response associated with the protection of 6 of 7 monkeys against viremia by wild-type dengue 2 virus. Neutralizing antibody titers to dengue 2 were significantly lower in YF-immune animals than in YF-naive monkeys and protection against challenge with wild-type dengue 2 virus was observed in only 2 of 11 YF-immune monkeys. An anamnestic response to dengue 2, indicated by a sharp increase of neutralizing antibody titers, was observed in the majority of the monkeys after challenge with wild-type virus. Virus attenuation was demonstrated using the standard monkey neurovirulence test. The 17D-D2 chimera caused significantly fewer histological lesions than the YF 17DD virus. The attenuated phenotype could also be inferred from the limited viremias compared to the YF 17DD vaccine. Overall, these results provide further support for the use of chimeric viruses for the development of a new live tetravalent dengue vaccine.

  3. Expansion of a unique region in the Marek's disease virus genome occurs concomitantly with attenuation but is not sufficient to cause attenuation.

    Science.gov (United States)

    Silva, R F; Reddy, S M; Lupiani, B

    2004-01-01

    Pathogenic Marek's disease viruses (MDVs) have two head-to-tail copies of a 132-bp repeat. As MDV is serially passaged in cell culture, the virus becomes attenuated and the number of copies of the 132-bp repeat increases from 2 to often more than 20 copies. To determine the role of the repeats in attenuation, we used five overlapping cosmid clones that spanned the MDV genome to reconstitute infectious virus (rMd5). By mutating the appropriate cosmids, we generated clones of infectious MDVs that contained zero copies of the 132-bp repeats, rMd5(Delta132); nine copies of the 132-bp repeats, rMd5(9-132); and nine copies of the 132-bp repeats inserted in the reverse orientation, rMd5(rev9-132). After two passages in cell culture, wild-type Md5, rMd5, and rMd5(Delta132) were stable. However, rMd5(9-132) and rMd5(rev9-132) contained a population of viruses that contained from 3 to over 20 copies of the repeats. A major 1.8-kb mRNA, containing two copies of the 132-bp repeat, was present in wild-type Md5 and rMd5 but was not present in rMd5(Delta132), rMd5(9-132), rMd5(rev9-132), or an attenuated MDV. Instead, the RNAs transcribed from the 132-bp repeat region in rMd5(9-132) and rMd5(rev9-132) closely resembled the pattern of RNAs transcribed in attenuated MDVs. When inoculated into susceptible day-old chicks, all viruses produced various lesions. Thus, expansion of the number of copies of 132-bp repeats, which accompanies attenuation, is not sufficient in itself to attenuate pathogenic MDVs.

  4. The yellow fever 17D virus as a platform for new live attenuated vaccines.

    Science.gov (United States)

    Bonaldo, Myrna C; Sequeira, Patrícia C; Galler, Ricardo

    2014-01-01

    The live-attenuated yellow fever 17D virus is one of the most outstanding human vaccines ever developed. It induces efficacious immune responses at a low production cost with a well-established manufacture process. These advantages make the YF17D virus attractive as a vector for the development of new vaccines. At the beginning of vector development studies, YF17D was genetically manipulated to express other flavivirus prM and E proteins, components of the viral envelope. While these 17D recombinants are based on the substitution of equivalent YF17D genes, other antigens from unrelated pathogens have also been successfully expressed and delivered by recombinant YF17D viruses employing alternative strategies for genetic manipulation of the YF17D genome. Herein, we discuss these strategies in terms of possibilities of single epitope or larger sequence expression and the main properties of these replication-competent viral platforms.

  5. Protection from Severe Influenza Virus Infections in Mice Carrying the Mx1 Influenza Virus Resistance Gene Strongly Depends on Genetic Background.

    OpenAIRE

    2015-01-01

    ABSTRACT Influenza virus infections represent a serious threat to human health. Both extrinsic and intrinsic factors determine the severity of influenza. The MX dynamin-like GTPase 1 (Mx1) gene has been shown to confer strong resistance to influenza A virus infections in mice. Most laboratory mouse strains, including C57BL/6J, carry nonsense or deletion mutations in Mx1 and thus a nonfunctional allele, whereas wild-derived mouse strains carry a wild-type Mx1 allele. Congenic C57BL/6J (B6-Mx1 ...

  6. A live attenuated vaccine prevents replication and transmission of H7N9 virus in mammals

    Science.gov (United States)

    Kong, Huihui; Zhang, Qianyi; Gu, Chunyang; Shi, Jianzhong; Deng, Guohua; Ma, Shujie; Liu, Jinxiong; Chen, Pucheng; Guan, Yuntao; Jiang, Yongping; Chen, Hualan

    2015-01-01

    The continued spread of the newly emerged H7N9 viruses among poultry in China, together with the emergence of drug-resistant variants and the possibility of human-to-human transmission, has spurred attempts to develop an effective vaccine. An MF59-adjuvant H7N9 inactivated vaccine is reported to be well-tolerated and immunogenic in humans; however a study in ferrets indicated that while a single dose of the inactivated H7N9 vaccine reduced disease severity, it did not prevent virus replication and transmission. In this study, we used reverse genetics to produce a cold-adapted, live attenuated H7N9 vaccine (H7N9/AAca) that contains wild-type HA and NA genes from AH/1, and the backbone of the cold-adapted influenza H2N2 A/Ann Arbor/6/60 virus (AAca). H7N9/AAca was attenuated in mice and ferrets, and induced robust neutralizing antibody responses in rhesus mice, ferrets, and guinea pigs immunized once or twice intranasally. The animals immunized twice were completely protected from H7N9 virus challenge. Importantly, the animals vaccinated once were fully protected from transmission when exposed to or in contact with the H7N9 virus-inoculated animals. These results demonstrate that a cold-adapted H7N9 vaccine can prevent H7N9 virus transmission; they provide a compelling argument for further testing of this vaccine in human trials. PMID:26058711

  7. Induction of influenza-specific mucosal immunity by an attenuated recombinant Sendai virus.

    Directory of Open Access Journals (Sweden)

    Thuc-vy L Le

    Full Text Available BACKGROUND: Many pathogens initiate infection at the mucosal surfaces; therefore, induction of mucosal immune responses is a first level of defense against infection and is the most powerful means of protection. Although intramuscular injection is widely used for vaccination and is effective at inducing circulating antibodies, it is less effective at inducing mucosal antibodies. METHODOLOGY/PRINCIPAL FINDINGS: Here we report a novel recombinant, attenuated Sendai virus vector (GP42-H1 in which the hemagglutinin (HA gene of influenza A virus was introduced into the Sendai virus genome as an additional gene. Infection of CV-1 cells by GP42-H1 resulted in cell surface expression of the HA protein. Intranasal immunization of mice with 1,000 plaque forming units (pfu of GP42-H1 induced HA-specific IgG and IgA antibodies in the blood, bronchoalveolar lavage fluid, fecal pellet extracts and saliva. The HA-specific antibody titer induced by GP42-H1 closely resembles the titer induced by sublethal infection by live influenza virus; however, in contrast to infection by influenza virus, immunization with GP42-H1 did not result in disease symptoms or the loss of body weight. In mice that were immunized with GP42-H1 and then challenged with 5LD(50 (1250 pfu of influenza virus, no significant weight loss was observed and other visual signs of morbidity were not detected. CONCLUSIONS: These results demonstrate that the GP42-H1 Sendai virus recombinant is able to confer full protection from lethal infection by influenza virus, supporting the conclusion that it is a safe and effective mucosal vaccine vector.

  8. Expression of the Surface Glycoproteins of Human Parainfluenza Virus Type 3 by Bovine Parainfluenza Virus Type 3, a Novel Attenuated Virus Vaccine Vector

    OpenAIRE

    Haller, Aurelia A.; Miller, Tessa; Mitiku, Misrach; Coelingh, Kathleen

    2000-01-01

    Bovine parainfluenza virus type 3 (bPIV3) is being evaluated as an intranasal vaccine for protection against human PIV3 (hPIV3). In young infants, the bPIV3 vaccine appears to be infectious, attenuated, immunogenic, and genetically stable, which are desirable characteristics for an RNA virus vector. To test the potential of the bPIV3 vaccine strain as a vector, an infectious DNA clone of bPIV3 was assembled and recombinant bPIV3 (r-bPIV3) was rescued. r-bPIV3 displayed a temperature-sensitive...

  9. Protective essential oil attenuates influenza virus infection: An in vitro study in MDCK cells

    Directory of Open Access Journals (Sweden)

    Metcalf Jordan P

    2010-11-01

    viability was only seen with concentrations of oil that were 2 to 6 times greater than the doses that inhibited viral infectivity. RT-PCR and western blotting demonstrated that oil treatment of the virus inhibited viral NP and NS1 protein, but not mRNA expression. Conclusions An essential oil blend significantly attenuates influenza virus PR8 infectivity in vitro without affecting viral binding or cellular internalization in MDCK cells. Oil treated virus continued to express viral mRNAs but had minimal expression of viral proteins, suggesting that the antiviral effect may be due to inhibition of viral protein translation.

  10. Recombinant constructions and infectivity analysis of tobacco mosaic virus and attenuated tomato mosaic virus N14 genomes

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The recombinant clones of pTN and pNT have been constructed by exchanging the coding regions of the movement proteins (MP), coat proteins (CP) and 3′noncoding regions between the cDNAs of the tobacco mosaic virus (Chinese Isolate, TMV-Cv) and the attenuated tomato mosaic virus N14 genomes, and used as templates for in vitro runoff transcription. Their transcripts have been used for tobacco infection assays. The infection results show that the transcripts of pTN and pNT are infectious. Local lesions were observed in the leaves of Nicotiana tabacum cv. Samsun NN inoculated with pTN transcript, but were fewer than those in the same kind of plant induced by pTMV-Cv transcript. Systemic symptoms were also observed in N. tabacum cv. Huangmiaoyu induced by pTN transcript, but were slighter than those on the same kind of tobacco induced by pTMV-Cv transcript. Local lesions were shown in N. tabacum cv. Samsun NN inoculated with pNT transcript, but were more than those in the same kind of plant induced by pN14 transcript while no systemic symptom was displayed in N. tabacum cv. Huangmiaoyu. These results suggest that the recombinant viruses of TN and NT are able to propagate in the assayed tobaccos, and they keep the most same phenotypic character with pTMV-Cv and pN14 transcripts, and TMV-Cv and N14 as well. The conjunctions between the replicase and the MP, CP and 3′noncoding regions are not stringent. Apparently there is a compatible function complementation between the homologous subgenomes of TMV-Cv and N14. From those above it could be probably presumed that the mutagenized replicase gene of N14 plays a major role in contributing to the virus attenuation while its mutagenized MP gene could avianize the symptoms of the infected tobaccos.

  11. Attenuation of virus production at high multiplicities of infection in Aureococcus anophagefferens

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Christopher M.; Bidle, Kay D., E-mail: bidle@marine.rutgers.edu

    2014-10-15

    Infection dynamics (saturation kinetics, infection efficiency, adsorption and burst size) for the Aureococcus anophagefferens-Brown Tide virus (AaV) system were investigated using susceptible and resistant strains. Adsorption assays revealed that virus affinity to the cell surface is a key determinant of infectivity. Saturation of infection occurred at a multiplicity of infection (MOI) of 8 viruses per host and resulted in ∼90–95% of infected cells, with burst sizes ranging from 164 to 191. Insight from the AaV genome implicates recycling of host nucleotides rather than de novo synthesis as a constraint on viral replication. Viral yields and mean burst sizes were significantly diminished with increasing MOI. This phenomenon, which was reminiscent of phage-induced ‘lysis from without’, appeared to be caused by viral contact and was unrelated to bacteria, signaling/toxic compounds, or defective interfering viruses. We posit that high-MOI effects attenuate viral proliferation in natural systems providing a negative feedback on virus-induced bloom collapse.

  12. Efficacy of a live attenuated vaccine in classical swine fever virus postnatally persistently infected pigs.

    Science.gov (United States)

    Muñoz-González, Sara; Perez-Simó, Marta; Muñoz, Marta; Bohorquez, José Alejandro; Rosell, Rosa; Summerfield, Artur; Domingo, Mariano; Ruggli, Nicolas; Ganges, Llilianne

    2015-07-09

    Classical swine fever (CSF) causes major losses in pig farming, with various degrees of disease severity. Efficient live attenuated vaccines against classical swine fever virus (CSFV) are used routinely in endemic countries. However, despite intensive vaccination programs in these areas for more than 20 years, CSF has not been eradicated. Molecular epidemiology studies in these regions suggests that the virus circulating in the field has evolved under the positive selection pressure exerted by the immune response to the vaccine, leading to new attenuated viral variants. Recent work by our group demonstrated that a high proportion of persistently infected piglets can be generated by early postnatal infection with low and moderately virulent CSFV strains. Here, we studied the immune response to a hog cholera lapinised virus vaccine (HCLV), C-strain, in six-week-old persistently infected pigs following post-natal infection. CSFV-negative pigs were vaccinated as controls. The humoral and interferon gamma responses as well as the CSFV RNA loads were monitored for 21 days post-vaccination. No vaccine viral RNA was detected in the serum samples and tonsils from CSFV postnatally persistently infected pigs for 21 days post-vaccination. Furthermore, no E2-specific antibody response or neutralising antibody titres were shown in CSFV persistently infected vaccinated animals. Likewise, no of IFN-gamma producing cell response against CSFV or PHA was observed. To our knowledge, this is the first report demonstrating the absence of a response to vaccination in CSFV persistently infected pigs.

  13. Sequence-Specific Fidelity Alterations Associated with West Nile Virus Attenuation in Mosquitoes.

    Directory of Open Access Journals (Sweden)

    Greta A Van Slyke

    2015-06-01

    Full Text Available High rates of error-prone replication result in the rapid accumulation of genetic diversity of RNA viruses. Recent studies suggest that mutation rates are selected for optimal viral fitness and that modest variations in replicase fidelity may be associated with viral attenuation. Arthropod-borne viruses (arboviruses are unique in their requirement for host cycling and may necessitate substantial genetic and phenotypic plasticity. In order to more thoroughly investigate the correlates, mechanisms and consequences of arbovirus fidelity, we selected fidelity variants of West Nile virus (WNV; Flaviviridae, Flavivirus utilizing selection in the presence of a mutagen. We identified two mutations in the WNV RNA-dependent RNA polymerase associated with increased fidelity, V793I and G806R, and a single mutation in the WNV methyltransferase, T248I, associated with decreased fidelity. Both deep-sequencing and in vitro biochemical assays confirmed strain-specific differences in both fidelity and mutational bias. WNV fidelity variants demonstrated host-specific alterations to replicative fitness in vitro, with modest attenuation in mosquito but not vertebrate cell culture. Experimental infections of colonized and field populations of Cx. quinquefaciatus demonstrated that WNV fidelity alterations are associated with a significantly impaired capacity to establish viable infections in mosquitoes. Taken together, these studies (i demonstrate the importance of allosteric interactions in regulating mutation rates, (ii establish that mutational spectra can be both sequence and strain-dependent, and (iii display the profound phenotypic consequences associated with altered replication complex function of flaviviruses.

  14. Replication-competent infectious hepatitis B virus vectors carrying substantially sized transgenes by redesigned viral polymerase translation.

    Directory of Open Access Journals (Sweden)

    Zihua Wang

    Full Text Available Viral vectors are engineered virus variants able to deliver nonviral genetic information into cells, usually by the same routes as the parental viruses. For several virus families, replication-competent vectors carrying reporter genes have become invaluable tools for easy and quantitative monitoring of replication and infection, and thus also for identifying antivirals and virus susceptible cells. For hepatitis B virus (HBV, a small enveloped DNA virus causing B-type hepatitis, such vectors are not available because insertions into its tiny 3.2 kb genome almost inevitably affect essential replication elements. HBV replicates by reverse transcription of the pregenomic (pg RNA which is also required as bicistronic mRNA for the capsid (core protein and the reverse transcriptase (Pol; their open reading frames (ORFs overlap by some 150 basepairs. Translation of the downstream Pol ORF does not involve a conventional internal ribosome entry site (IRES. We reasoned that duplicating the overlap region and providing artificial IRES control for translation of both Pol and an in-between inserted transgene might yield a functional tricistronic pgRNA, without interfering with envelope protein expression. As IRESs we used a 22 nucleotide element termed Rbm3 IRES to minimize genome size increase. Model plasmids confirmed its activity even in tricistronic arrangements. Analogous plasmids for complete HBV genomes carrying 399 bp and 720 bp transgenes for blasticidin resistance (BsdR and humanized Renilla green fluorescent protein (hrGFP produced core and envelope proteins like wild-type HBV; while the hrGFP vector replicated poorly, the BsdR vector generated around 40% as much replicative DNA as wild-type HBV. Both vectors, however, formed enveloped virions which were infectious for HBV-susceptible HepaRG cells. Because numerous reporter and effector genes with sizes of around 500 bp or less are available, the new HBV vectors should become highly useful tools to

  15. Immunogenicity of recombinant attenuated Salmonella enterica serovar Typhimurium vaccine strains carrying a gene that encodes Eimeria tenella antigen SO7.

    Science.gov (United States)

    Konjufca, Vjollca; Jenkins, Mark; Wang, Shifeng; Juarez-Rodriguez, Maria Dolores; Curtiss, Roy

    2008-12-01

    Recombinant attenuated Salmonella vaccines against avian coccidiosis were developed to deliver Eimeria species antigens to the lymphoid tissues of chickens via the type 3 secretion system (T3SS) and the type 2 secretion system (T2SS) of Salmonella. For antigen delivery via the T3SS, the Eimeria tenella gene encoding sporozoite antigen SO7 was cloned downstream of the translocation domain of the Salmonella enterica serovar Typhimurium sopE gene in the parental pYA3868 and pYA3870 vectors to generate pYA4156 and pYA4157. Newly constructed T3SS vectors were introduced into host strain chi8879 (Delta phoP233 Delta sptP1033::xylE Delta asdA16), an attenuated derivative of the highly virulent UK-1 strain. The SopE-SO7 fusion protein was secreted by the T3SS of Salmonella. The vector pYA4184 was constructed for delivery of the SO7 antigen via the T2SS. The SO7 protein was toxic to Salmonella when larger amounts were synthesized; thus, the synthesis of this protein was placed under the control of the lacI repressor gene, whose expression in turn was dependent on the amount of available arabinose in the medium. The pYA4184 vector was introduced into host strain chi9242 (Delta phoP233 Delta asdA16 Delta araBAD23 Delta relA198::araC P(BAD) lacI TT [TT is the T4ipIII transcription terminator]). In addition to SO7, for immunization and challenge studies we used the EAMZ250 antigen of Eimeria acervulina, which was previously shown to confer partial protection against E. acervulina challenge when it was delivered via the T3SS. Immunization of chickens with a combination of the SO7 and EAMZ250 antigens delivered via the T3SS induced superior protection against challenge by E. acervulina. In contrast, chickens immunized with SO7 that was delivered via the T2SS of Salmonella were better protected from challenge by E. tenella.

  16. Epstein-Barr virus-encoded EBNA1 and ZEBRA: targets for therapeutic strategies against EBV-carrying cancers.

    Science.gov (United States)

    Daskalogianni, Chrysoula; Pyndiah, Slovénie; Apcher, Sébastien; Mazars, Anne; Manoury, Bénédicte; Ammari, Nisrine; Nylander, Karin; Voisset, Cécile; Blondel, Marc; Fåhraeus, Robin

    2015-01-01

    The EBV-encoded EBNA1 was first discovered 40 years ago, approximately 10 years after the presence of EBV had been demonstrated in Burkitt's lymphoma cells. It took another 10 years before the functions of EBNA1 in maintaining the viral genome were revealed, and it has since been shown to be an essential viral factor expressed in all EBV-carrying cells. Apart from serving to maintain the viral episome and to control viral replication and gene expression, EBNA1 also harbours a cis-acting mechanism that allows virus-carrying host cells to evade the immune system. This relates to a particular glycine-alanine repeat (GAr) within EBNA1 that has the capacity to suppress antigen presentation to the major histocompatibility complex (MHC) class I pathway. We discuss the role of the GAr sequence at the level of mRNA translation initiation, rather than at the protein level, as at least part of the mechanism to avoid MHC presentation. Interfering with this mechanism has become the focus of the development of immune-based therapies against EBV-carrying cancers, and some lead compounds that affect translation of GAr-carrying mRNAs have been identified. In addition, we describe the EBV-encoded ZEBRA factor and the switch from the latent to the lytic cycle as an alternative virus-specific target for treating EBV-carrying cancers. Understanding the molecular mechanisms of how EBNA1 and ZEBRA interfere with cellular pathways not only opens new therapeutic approaches but continues to reveal new cell-biological insights on the interplay between host and virus. This review is a tale of discoveries relating to how EBNA1 and ZEBRA have emerged as targets for specific cancer therapies against EBV-carrying diseases, and serves as an illustration of how mRNA translation can play roles in future immune-based strategies to target viral disease.

  17. Generation and Characterization of Live Attenuated Influenza A(H7N9 Candidate Vaccine Virus Based on Russian Donor of Attenuation.

    Directory of Open Access Journals (Sweden)

    Svetlana Shcherbik

    Full Text Available Avian influenza A (H7N9 virus has emerged recently and continues to cause severe disease with a high mortality rate in humans prompting the development of candidate vaccine viruses. Live attenuated influenza vaccines (LAIV are 6:2 reassortant viruses containing the HA and NA gene segments from wild type influenza viruses to induce protective immune responses and the six internal genes from Master Donor Viruses (MDV to provide temperature sensitive, cold-adapted and attenuated phenotypes.LAIV candidate A/Anhui/1/2013(H7N9-CDC-LV7A (abbreviated as CDC-LV7A, based on the Russian MDV, A/Leningrad/134/17/57 (H2N2, was generated by classical reassortment in eggs and retained MDV temperature-sensitive and cold-adapted phenotypes. CDC-LV7A had two amino acid substitutions N123D and N149D (H7 numbering in HA and one substitution T10I in NA. To evaluate the role of these mutations on the replication capacity of the reassortants in eggs, the recombinant viruses A(H7N9RG-LV1 and A(H7N9RG-LV2 were generated by reverse genetics. These changes did not alter virus antigenicity as ferret antiserum to CDC-LV7A vaccine candidate inhibited hemagglutination by homologous A(H7N9 virus efficiently. Safety studies in ferrets confirmed that CDC-LV7A was attenuated compared to wild-type A/Anhui/1/2013. In addition, the genetic stability of this vaccine candidate was examined in eggs and ferrets by monitoring sequence changes acquired during virus replication in the two host models. No changes in the viral genome were detected after five passages in eggs. However, after ten passages additional mutations were detected in the HA gene. The vaccine candidate was shown to be stable in the ferret model; post-vaccination sequence data analysis showed no changes in viruses collected in nasal washes present at day 5 or day 7.Our data indicate that the A/Anhui/1/2013(H7N9-CDC-LV7A reassortant virus is a safe and genetically stable candidate vaccine virus that is now available for

  18. Generation and Characterization of Live Attenuated Influenza A(H7N9) Candidate Vaccine Virus Based on Russian Donor of Attenuation

    Science.gov (United States)

    Shcherbik, Svetlana; Pearce, Nicholas; Balish, Amanda; Jones, Joyce; Thor, Sharmi; Davis, Charles Todd; Pearce, Melissa; Tumpey, Terrence; Cureton, David; Chen, Li-Mei; Villanueva, Julie; Bousse, Tatiana L.

    2015-01-01

    Background Avian influenza A (H7N9) virus has emerged recently and continues to cause severe disease with a high mortality rate in humans prompting the development of candidate vaccine viruses. Live attenuated influenza vaccines (LAIV) are 6:2 reassortant viruses containing the HA and NA gene segments from wild type influenza viruses to induce protective immune responses and the six internal genes from Master Donor Viruses (MDV) to provide temperature sensitive, cold-adapted and attenuated phenotypes. Methodology/Principal Findings LAIV candidate A/Anhui/1/2013(H7N9)-CDC-LV7A (abbreviated as CDC-LV7A), based on the Russian MDV, A/Leningrad/134/17/57 (H2N2), was generated by classical reassortment in eggs and retained MDV temperature-sensitive and cold-adapted phenotypes. CDC-LV7A had two amino acid substitutions N123D and N149D (H7 numbering) in HA and one substitution T10I in NA. To evaluate the role of these mutations on the replication capacity of the reassortants in eggs, the recombinant viruses A(H7N9)RG-LV1 and A(H7N9)RG-LV2 were generated by reverse genetics. These changes did not alter virus antigenicity as ferret antiserum to CDC-LV7A vaccine candidate inhibited hemagglutination by homologous A(H7N9) virus efficiently. Safety studies in ferrets confirmed that CDC-LV7A was attenuated compared to wild-type A/Anhui/1/2013. In addition, the genetic stability of this vaccine candidate was examined in eggs and ferrets by monitoring sequence changes acquired during virus replication in the two host models. No changes in the viral genome were detected after five passages in eggs. However, after ten passages additional mutations were detected in the HA gene. The vaccine candidate was shown to be stable in the ferret model; post-vaccination sequence data analysis showed no changes in viruses collected in nasal washes present at day 5 or day 7. Conclusions/Significance Our data indicate that the A/Anhui/1/2013(H7N9)-CDC-LV7A reassortant virus is a safe and

  19. Characterization of an attenuated TE3L-deficient vaccinia virus Tian Tan strain.

    Science.gov (United States)

    Wang, Yuhang; Kan, Shifu; Du, Shouwen; Qi, Yanxin; Wang, Jinhui; Liu, Liming; Ji, Huifan; He, Dongyun; Wu, Na; Li, Chang; Chi, Baorong; Li, Xiao; Jin, Ningyi

    2012-12-01

    An attenuated vaccinia virus (VACV), TE3L(-)VTT, was evaluated for virulence and safety to determine its potential use as a vaccine or as a recombinant virus vector to express foreign genes. The virulence of TE3L(-)VTT was compared with that of the wild-type VTT both in vivo and in vitro. The humoral and cellular immune responses were detected in a mouse model to test the vaccine efficacy of the TE3L mutant. The results suggested that deletion of the TE3L gene decreased the virulence and neurovirulence significantly in mice and rabbit models, yet retained the immunogenicity. Thus, the deletion of TE3L improved the safety of the VTT vector; this approach may yield a valuable resource for studies of recombinant VACV-vectored vaccines.

  20. Transcriptome Analysis of the Small Brown Planthopper, Laodelphax striatellus Carrying Rice stripe virus

    Directory of Open Access Journals (Sweden)

    Joo Hyun Lee

    2013-09-01

    Full Text Available Rice stripe virus (RSV, the type member of the genus Tenuivirus, transmits by the feeding behavior of small brown planthopper (SBPH, Laodelphax striatellus. To investigate the interactions between the virus and vector insect, total RNA was extracted from RSV-viruliferous SBPH (RVLS and non-viruliferous SBPH (NVLS adults to construct expressed sequence tag databases for comparative transcriptome analysis. Over 30 million bases were sequenced by 454 pyrosequencing to construct 1,538 and 953 of isotigs from the mRNA of RVLS and NVLS, respectively. The gene ontology (GO analysis demonstrated that both libraries have similar GO structures, however, the gene expression pattern analysis revealed that 17.8% and 16.8% of isotigs were up- and down-regulated significantly in the RVLS, respectively. These RSV-dependently regulated genes possibly have important roles in the physiology of SBPH, transmission of RSV, and RSV and SBPH interaction.

  1. Deliberate attenuation of chikungunya virus by adaptation to heparan sulfate-dependent infectivity: a model for rational arboviral vaccine design.

    Science.gov (United States)

    Gardner, Christina L; Hritz, Jozef; Sun, Chengqun; Vanlandingham, Dana L; Song, Timothy Y; Ghedin, Elodie; Higgs, Stephen; Klimstra, William B; Ryman, Kate D

    2014-02-01

    Mosquito-borne chikungunya virus (CHIKV) is a positive-sense, single-stranded RNA virus from the genus Alphavirus, family Togaviridae, which causes fever, rash and severe persistent polyarthralgia in humans. Since there are currently no FDA licensed vaccines or antiviral therapies for CHIKV, the development of vaccine candidates is of critical importance. Historically, live-attenuated vaccines (LAVs) for protection against arthropod-borne viruses have been created by blind cell culture passage leading to attenuation of disease, while maintaining immunogenicity. Attenuation may occur via multiple mechanisms. However, all examined arbovirus LAVs have in common the acquisition of positively charged amino acid substitutions in cell-surface attachment proteins that render virus infection partially dependent upon heparan sulfate (HS), a ubiquitously expressed sulfated polysaccharide, and appear to attenuate by retarding dissemination of virus particles in vivo. We previously reported that, like other wild-type Old World alphaviruses, CHIKV strain, La Réunion, (CHIKV-LR), does not depend upon HS for infectivity. To deliberately identify CHIKV attachment protein mutations that could be combined with other attenuating processes in a LAV candidate, we passaged CHIKV-LR on evolutionarily divergent cell-types. A panel of single amino acid substitutions was identified in the E2 glycoprotein of passaged virus populations that were predicted to increase electrostatic potential. Each of these substitutions was made in the CHIKV-LR cDNA clone and comparisons of the mutant viruses revealed surface exposure of the mutated residue on the spike and sensitivity to competition with the HS analog, heparin, to be primary correlates of attenuation in vivo. Furthermore, we have identified a mutation at E2 position 79 as a promising candidate for inclusion in a CHIKV LAV.

  2. Deliberate attenuation of chikungunya virus by adaptation to heparan sulfate-dependent infectivity: a model for rational arboviral vaccine design.

    Directory of Open Access Journals (Sweden)

    Christina L Gardner

    2014-02-01

    Full Text Available Mosquito-borne chikungunya virus (CHIKV is a positive-sense, single-stranded RNA virus from the genus Alphavirus, family Togaviridae, which causes fever, rash and severe persistent polyarthralgia in humans. Since there are currently no FDA licensed vaccines or antiviral therapies for CHIKV, the development of vaccine candidates is of critical importance. Historically, live-attenuated vaccines (LAVs for protection against arthropod-borne viruses have been created by blind cell culture passage leading to attenuation of disease, while maintaining immunogenicity. Attenuation may occur via multiple mechanisms. However, all examined arbovirus LAVs have in common the acquisition of positively charged amino acid substitutions in cell-surface attachment proteins that render virus infection partially dependent upon heparan sulfate (HS, a ubiquitously expressed sulfated polysaccharide, and appear to attenuate by retarding dissemination of virus particles in vivo. We previously reported that, like other wild-type Old World alphaviruses, CHIKV strain, La Réunion, (CHIKV-LR, does not depend upon HS for infectivity. To deliberately identify CHIKV attachment protein mutations that could be combined with other attenuating processes in a LAV candidate, we passaged CHIKV-LR on evolutionarily divergent cell-types. A panel of single amino acid substitutions was identified in the E2 glycoprotein of passaged virus populations that were predicted to increase electrostatic potential. Each of these substitutions was made in the CHIKV-LR cDNA clone and comparisons of the mutant viruses revealed surface exposure of the mutated residue on the spike and sensitivity to competition with the HS analog, heparin, to be primary correlates of attenuation in vivo. Furthermore, we have identified a mutation at E2 position 79 as a promising candidate for inclusion in a CHIKV LAV.

  3. Generation of an attenuated Tiantan vaccinia virus by deletion of the ribonucleotide reductase large subunit.

    Science.gov (United States)

    Kan, Shifu; Jia, Peng; Sun, Lili; Hu, Ningning; Li, Chang; Lu, Huijun; Tian, Mingyao; Qi, Yanxin; Jin, Ningyi; Li, Xiao

    2014-09-01

    Attenuation of the virulence of vaccinia Tiantan virus (VTT) underlies the strategy adopted for mass vaccination campaigns. This strategy provides advantages of safety and efficacy over traditional vaccines and is aimed at minimization of adverse health effects. In this study, a mutant form of the virus, MVTT was derived from VTT by deletion of the ribonucleotide reductase large subunit (R1) (TI4L). Compared to wild-type parental (VTT) and revertant (VTT-rev) viruses, virulence of the mutant MVTT was reduced by 100-fold based on body weight reduction and by 3,200-fold based on determination of the intracranial 50% lethal infectious dose. However, the immunogenicity of MVTT was equivalent to that of the parental VTT. We also demonstrated that the TI4L gene is not required for efficient replication. These data support the conclusion that MVTT can be used as a replicating virus vector or as a platform for the development of vaccines against infectious diseases and for cancer therapy.

  4. Antibody response against three widespread bovine viruses is not impaired in Holstein cattle carrying bovine leukocyte antigen DRB3.2 alleles associated with bovine leukemia virus resistance.

    Science.gov (United States)

    Juliarena, M A; Poli, M; Ceriani, C; Sala, L; Rodríguez, E; Gutierrez, S; Dolcini, G; Odeon, A; Esteban, E N

    2009-01-01

    Due to the wide dissemination of bovine leukemia virus (BLV) infection among dairy cattle, control and eradication programs based on serological detection of infected cattle and subsequent culling face a major economic task. In Argentina, genetic selection of cattle carrying alleles of the bovine leukocyte antigen (BoLA) DRB3.2 gene associated with BLV-infection resistance, like *0902, emerges as the best additional tool toward controlling virus spread. A potential risk in expanding or segregating BoLA selected populations of cattle is that it might increase susceptibility to other common viruses. Special concern raises the strong association found between low proviral load and low antibody titer against major BLV structural proteins. This phenomenon might depend on host genetic factors influencing other viruses requiring, unlike BLV, strong and long-lasting humoral immune response to prevent infection. In this study, we demonstrate that there is no association among neutralizing antibody titers against foot and mouth disease virus, bovine viral diarrhea virus, or bovine herpesvirus type 1 and polymorphism of the BoLA DRB3.2 gene. Conversely, there is strong association between BoLA DRB3.2*0902 and low antibody titers against 2 BLV structural proteins--env gp51 and gag p24--to date, the best BLV resistance marker. There is also significant association between low antibody titers against gp51 and p24 and BoLA DRB3.2*1701 and low antibody titers against p24 and BoLA DRB3.2*1101 or 02. Our data suggest that increasing BoLA-selected BLV-resistant cattle or segregating BoLA-associated alleles to BLV susceptibility would not affect the resistance or the predisposition to bovine viral diarrhea virus, bovine herpesvirus type 1, or foot and mouth disease virus infection.

  5. Heterotypic Dengue Infection with Live Attenuated Monotypic Dengue Virus Vaccines: Implications for Vaccination of Populations in Areas Where Dengue Is Endemic

    OpenAIRE

    Anna P Durbin; Schmidt, Alexander; Elwood, Dan; Wanionek, Kimberli A.; Lovchik, Janece; Thumar, Bhavin; Murphy, Brian R.; Whitehead, Stephen S.

    2011-01-01

    Background. Because infection with any of the 4 Dengue virus serotypes may elicit both protective neutralizing antibodies and nonneutralizing antibodies capable of enhancing subsequent heterotypic Dengue virus infections, the greatest risk for severe dengue occurs during a second, heterotypic Dengue virus infection. It remains unclear whether the replication of live attenuated vaccine viruses will be similarly enhanced when administered to Dengue-immune individuals.

  6. Single-dose attenuated Vesiculovax vaccines protect primates against Ebola Makona virus.

    Science.gov (United States)

    Mire, Chad E; Matassov, Demetrius; Geisbert, Joan B; Latham, Theresa E; Agans, Krystle N; Xu, Rong; Ota-Setlik, Ayuko; Egan, Michael A; Fenton, Karla A; Clarke, David K; Eldridge, John H; Geisbert, Thomas W

    2015-04-30

    The family Filoviridae contains three genera, Ebolavirus (EBOV), Marburg virus, and Cuevavirus. Some members of the EBOV genus, including Zaire ebolavirus (ZEBOV), can cause lethal haemorrhagic fever in humans. During 2014 an unprecedented ZEBOV outbreak occurred in West Africa and is still ongoing, resulting in over 10,000 deaths, and causing global concern of uncontrolled disease. To meet this challenge a rapid-acting vaccine is needed. Many vaccine approaches have shown promise in being able to protect nonhuman primates against ZEBOV. In response to the current ZEBOV outbreak several of these vaccines have been fast tracked for human use. However, it is not known whether any of these vaccines can provide protection against the new outbreak Makona strain of ZEBOV. One of these approaches is a first-generation recombinant vesicular stomatitis virus (rVSV)-based vaccine expressing the ZEBOV glycoprotein (GP) (rVSV/ZEBOV). To address safety concerns associated with this vector, we developed two candidate, further-attenuated rVSV/ZEBOV vaccines. Both attenuated vaccines produced an approximately tenfold lower vaccine-associated viraemia compared to the first-generation vaccine and both provided complete, single-dose protection of macaques from lethal challenge with the Makona outbreak strain of ZEBOV.

  7. Replication fitness determines high virulence of influenza A virus in mice carrying functional Mx1 resistance gene.

    Science.gov (United States)

    Grimm, Daniel; Staeheli, Peter; Hufbauer, Martin; Koerner, Iris; Martínez-Sobrido, Luis; Solórzano, Alicia; García-Sastre, Adolfo; Haller, Otto; Kochs, Georg

    2007-04-17

    The IFN-induced resistance factor Mx1 is a critical component of innate immunity against influenza A viruses (FLUAV) in mice. Animals carrying a wild-type Mx1 gene (Mx1(+/+)) differ from regular laboratory mice (Mx1(-/-)) in that they are highly resistant to infection with standard FLUAV strains. We identified an extraordinary variant of the FLUAV strain, A/PR/8/34 (H1N1) (designated hvPR8), which is unusually virulent in Mx1(+/+) mice. hvPR8 was well controlled in Mx1(+/+) but not Mx1(-/-) mice provided that the animals were treated with IFN before infection, indicating that hvPR8 exhibits normal sensitivity to growth restriction by Mx1. hvPR8 multiplied much faster than standard PR8 early in infection because of highly efficient viral gene expression in infected cells. Studies with reassortant viruses containing defined genome segments of both hvPR8 and standard PR8 demonstrated that the HA, neuraminidase, and polymerase genes of hvPR8 all contributed to virulence, indicating that efficient host cell entry and early gene expression renders hvPR8 highly pathogenic. These results reveal a surprisingly simple concept of how influenza viruses may gain virulence and illustrate that high speed of virus growth can outcompete the antiviral response of the infected host.

  8. Immunogenicity of transmissible gastroenteritis virus (TGEV) M gene delivered by attenuated Salmonella typhimurium in mice.

    Science.gov (United States)

    Qing, Ying; Liu, Jiawen; Huang, Xiaobo; Li, Yaqing; Zhang, Yudi; Chen, Jie; Wen, Xintian; Cao, Sanjie; Wen, Yiping; Wu, Rui; Yan, Qigui; Ma, Xiaoping

    2016-04-01

    Attenuated Salmonella typhimurium (S. typhimurium) was selected as a transgenic vehicle for the development of live mucosal vaccines against transmissible gastroenteritis virus (TGEV) based on the M gene. An approximate 1.0 kb DNA fragment, encoding for glycoprotein M, was amplified by RT-PCR and cloned into eukaryotic expression vector pVAX1. The recombinant plasmid pVAX-M was transformed by electroporation into attenuated S. typhimurium SL7207, and the expression and translation of the pVAX-M delivered by recombinant S. typhimurium SL7207 (pVAX-M) was detected both in vitro and in vivo. BALB/c mice were inoculated orally with SL7207 (pVAX-M) at different dosages to evaluate safety of the vaccines. The bacterium was safe to mice at a dosage of 2 × 10(9) CFU, almost eliminated from the spleen and liver at week 4 post-immunization and eventually cleared at week 6. Mice immunized with 1 × 10(9) CFU of SL7207 (pVAX-M) elicited specific anti-TGEV local mucosal and humoral responses including levels of IgA, IgG, IL-4, and IFN-γ as measured by indirect ELISA assay. Moreover, the control groups (pVAX group, PBS group) maintained at a normal level during week 4-8 post-immunization. The results indicated that attenuated S. typhimurium could be used as a delivery vector for oral immunization of TGEV M gene vaccine.

  9. 42 CFR 71.56 - African rodents and other animals that may carry the monkeypox virus.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false African rodents and other animals that may carry... HUMAN SERVICES QUARANTINE, INSPECTION, LICENSING FOREIGN QUARANTINE Importations § 71.56 African rodents... import or attempt to import any rodents, whether dead or alive, that were obtained, directly...

  10. In vitro reassortment between endemic H1N2 and 2009 H1N1 pandemic swine influenza viruses generates attenuated viruses.

    Directory of Open Access Journals (Sweden)

    Ben M Hause

    Full Text Available The pandemic H1N1 (pH1N1 influenza virus was first reported in humans in the spring of 2009 and soon thereafter was identified in numerous species, including swine. Reassortant viruses, presumably arising from the co-infection of pH1N1 and endemic swine influenza virus (SIV, were subsequently identified from diagnostic samples collected from swine. In this study, co-infection of swine testicle (ST cells with swine-derived endemic H1N2 (MN745 and pH1N1 (MN432 yielded two reassortant H1N2 viruses (R1 and R2, both possessing a matrix gene derived from pH1N1. In ST cells, the reassortant viruses had growth kinetics similar to the parental H1N2 virus and reached titers approximately 2 log(10 TCID(50/mL higher than the pH1N1 virus, while in A549 cells these viruses had similar growth kinetics. Intranasal challenge of pigs with H1N2, pH1N1, R1 or R2 found that all viruses were capable of infecting and transmitting between direct contact pigs as measured by real time reverse transcription PCR of nasal swabs. Lung samples were also PCR-positive for all challenge groups and influenza-associated microscopic lesions were detected by histology. Interestingly, infectious virus was detected in lung samples for pigs challenged with the parental H1N2 and pH1N1 at levels significantly higher than either reassortant virus despite similar levels of viral RNA. Results of our experiment suggested that the reassortant viruses generated through in vitro cell culture system were attenuated without gaining any selective growth advantage in pigs over the parental lineages. Thus, reassortant influenza viruses described in this study may provide a good system to study genetic basis of the attenuation and its mechanism.

  11. Oral Delivery of a Novel Attenuated Salmonella Vaccine Expressing Influenza A Virus Proteins Protects Mice against H5N1 and H1N1 Viral Infection.

    Directory of Open Access Journals (Sweden)

    Zenglin Pei

    Full Text Available Attenuated strains of invasive enteric bacteria, such as Salmonella, represent promising gene delivery agents for nucleic acid-based vaccines as they can be administrated orally. In this study, we constructed a novel attenuated strain of Salmonella for the delivery and expression of the hemagglutinin (HA and neuraminidase (NA of a highly pathogenic H5N1 influenza virus. We showed that the constructed Salmonella strain exhibited efficient gene transfer activity for HA and NA expression and little cytotoxicity and pathogenicity in mice. Using BALB/c mice as the model, we evaluated the immune responses and protection induced by the constructed Salmonella-based vaccine. Our study showed that the Salmonella-based vaccine induced significant production of anti-HA serum IgG and mucosal IgA, and of anti-HA interferon-γ producing T cells in orally vaccinated mice. Furthermore, mice orally vaccinated with the Salmonella vaccine expressing viral HA and NA proteins were completely protected from lethal challenge of highly pathogenic H5N1 as well as H1N1 influenza viruses while none of the animals treated with the Salmonella vaccine carrying the empty expression vector with no viral antigen expression was protected. These results suggest that the Salmonella-based vaccine elicits strong antigen-specific humoral and cellular immune responses and provides effective immune protection against multiple strains of influenza viruses. Furthermore, our study demonstrates the feasibility of developing novel attenuated Salmonella strains as new oral vaccine vectors against influenza viruses.

  12. Generation and characterization of a cold-adapted attenuated live H3N2 subtype influenza virus vaccine candidate

    Institute of Scientific and Technical Information of China (English)

    AN Wen-qi; LIU Xiu-fan; WANG Xi-liang; YANG Peng-hui; DUAN Yue-qiang; LUO De-yan; TANG Chong; JIA Wei-hong; XING Li; SHI Xin-fu; ZHANG Yu-jing

    2009-01-01

    Background H3N2 subtype influenza A viruses have been identified in humans worldwide, raising concerns about their pandemic potential and prompting the development of candidate vaccines to protect humans against this subtype of influenza A virus. The aim of this study was to establish a system for rescuing of a cold-adapted high-yielding H3N2 subtype human influenza virus by reverse genetics. Methods In order to generate better and safer vaccine candidate viruses, a cold-adapted high yielding reassortant H3N2 influenza A virus was genetically constructed by reverse genetics and was designated as rgAA-H3N2. The rgAA-H3N2 virus contained HA and NA genes from an epidemic strain A/Wisconsin/67/2005 (H3N2) in a background of internal genes derived from the master donor viruses (MDV), cold-adapted (ca), temperature sensitive (te), live attenuated influenza virus strain A/Ann Arbor/6/60 (MDV-A). Results In this presentation, the virus HA titer of rgAA-H3N2 in the allantoic fluid from infected embryonated eggs was as high as 1:1024. A fluorescent focus assay (FFU) was performed 24-36 hours post-infection using a specific antibody and bright staining was used for determining the virus titer. The allantoic fluid containing the recovered influenza virus was analyzed in a hemagglutination inhibition (HI) test and the specific inhibition was found. Conclusion The results mentioned above demonstrated that cold-adapted, attenuated reassortant H3N2 subtype influenza A virus was successfully generated, which laid a good foundation for the further related research.

  13. Proviral genomic sequence analysis of Chinese donkey leukocyte attenuated equine infectious anemia virus vaccine and its parental virus strain Liaoning

    Institute of Scientific and Technical Information of China (English)

    王柳; 童光志; 刘红全; 杨志彪; 仇华吉; 孔宪刚; 王玫

    2002-01-01

    Proviral DNA was extracted from donkey leukocyte infected with Chinese donkey leukocyte attenuated equine infectious anemia virus(DLA-EIAV), and peripheral blood lymphocytes(PBL) from a horse infected with the virulent EIAV strain Liaoning(EIAV L). The entire proviral DNA from both viruses was cloned and sequenced. The lengths of complete genomic sequences of DLA-EIAV and EIAV L provirus were 8266 bp and 8235 bp, respectively. Sequence comparison indicated that DLA-EIAV shares 97.0% and 97.5% in sequence homology with EIAV L and donkey-adapted EIAV(DA-EIAV), respectively. Lots of variations occurred in long terminal repeat(LTR, consisting of U3, R, U5), ORF S2, and env regions between DLA-EIAV and EIAV L. The nucleotide sequence differences of the two viruses in U3, R, U5, ORF S2, and env are 13.2%, 7.5%, 5.1%, 3.9%, and 2.7%, respectively, and predicted amino acid sequence differences in env and S2 coding regions are 4.4% and 8.8%, respectively. Six conserved regions are characterized in Gp90. There is a cis-activating GATA motif in ENH of DLA-EIAV and EIAV L. Two N-linked glycosylation sites disappeared in DLA-EIAV Gp90 in comparison with that of EIAV L. A bHLH transcription factor binding consensus sequence was found in LTR of DLA-EIAV but not in EIAV L. Furthermore, there is a mutation in the stem of DLA-EIAV TAR resulting in formation of a uridine tuber. Further study is needed to uncover the relationship between sequence changes and their biological functions of DLA-EIAV and L.

  14. Amoebas as mimivirus bunkers: increased resistance to UV light, heat and chemical biocides when viruses are carried by amoeba hosts.

    Science.gov (United States)

    Boratto, Paulo V M; Dornas, Fábio P; Andrade, Kétyllen R; Rodrigues, Rodrigo; Peixoto, Felipe; Silva, Lorena C F; La Scola, Bernard; Costa, Adriana Oliveira; de Almeida, Gabriel Magno Freitas; Kroon, Erna G; Abrahão, Jônatas S

    2014-05-01

    Amoebas of the genus Acanthamoeba are protists that are associated with human disease and represent a public health concern. They can harbor pathogenic microorganisms, acting as a platform for pathogen replication. Acanthamoeba polyphaga mimivirus (APMV), the type species of the genus Mimivirus, family Mimiviridae, represents the largest group of amoeba-associated viruses that has been described to date. Recent studies have demonstrated that APMV and other giant viruses may cause pneumonia. Amoebas can survive in most environments and tolerate various adverse conditions, including UV light irradiation, high concentrations of disinfectants, and a broad range of temperatures. However, it is unknown how the amoebal intracellular environment influences APMV stability and resistance to adverse conditions. Therefore, in this work, we evaluated the stability of APMV, either purified or carried by the amoeba host, under extreme conditions, including UV irradiation, heat and exposure to six different chemical biocides. After each treatment, the virus was titrated in amoebas using the TCID50 method. APMV was more stable in all resistance tests performed when located inside its host. Our results demonstrate that Acanthamoeba acts as a natural bunker for APMV, increasing viral resistance to extreme physical and chemical conditions. The data raise new questions regarding the survival of APMV in nature and in hospital environments.

  15. A Bioinformatics Method for the Design of Live Attenuated Virus Vaccine Utilizing Host MicroRNA Response Elements.

    Science.gov (United States)

    Wichadakul, Duangdao

    2016-01-01

    The host microRNA machinery has been employed to control viral replication. To improve safety for live attenuated virus vaccines, the binding sites of the host microRNAs, so-called microRNA response elements (MREs), were incorporated into the virus sequences. These MREs were typically designed for a specific host microRNA and virus sequence with the effectiveness evaluated by experimental trials. Here, we describe a computational flow that can be used to simultaneously design and prioritize the effective MREs in large-scale.

  16. PREDICTING ATTENUATION OF VIRUSES DURING PERCOLATION IN SOILS: 2. USER'S GUIDE TO THE VIRULO 1.0 COMPUTER MODEL

    Science.gov (United States)

    In the EPA document Predicting Attenuation of Viruses During Percolation in Soils 1. Probabilistic Model the conceptual, theoretical, and mathematical foundations for a predictive screening model were presented. In this current volume we present a User's Guide for the computer mo...

  17. Deletion of the thymidine kinase gene induces complete attenuation of the Georgia isolate of African swine fever virus

    Science.gov (United States)

    African swine fever virus (ASFV) is the etiological agent of a contagious and often lethal viral disease of domestic pigs. There are no vaccines to control Africa swine fever (ASF). Experimental vaccines have been developed using genetically modified live attenuated ASFVs obtained by specifically de...

  18. Capsid proteins from field strains of foot-and-mouth disease virus confer a pathogenic phenotype in cattle on an attenuated, cell-culture-adapted virus

    DEFF Research Database (Denmark)

    Bøtner, Anette; Kakker, Naresh K.; Barbezange, Cyril

    2011-01-01

    Chimeric foot-and-mouth disease viruses (FMDVs) have been generated from plasmids containing full-length FMDV cDNAs and characterized. The parental virus cDNA was derived from the cell-culture-adapted O1Kaufbeuren B64 (O1K B64) strain. Chimeric viruses, containing capsid coding sequences derived...... cells than the rescued parental O1K B64 virus. The two chimeric viruses displayed the expected antigenicity in serotype-specific antigen ELISAs. Following inoculation of each virus into cattle, the rescued O1K B64 strain proved to be attenuated whereas, with each chimeric virus, typical clinical signs...... from the O/UKG/34/2001 or A/Turkey 2/2006 field viruses, were constructed using the backbone from the O1K B64 cDNA, and viable viruses (O1K/O-UKG and O1K/A-Tur, respectively) were successfully rescued in each case. These viruses grew well in primary bovine thyroid cells but grew less efficiently in BHK...

  19. Association of the Host Immune Response with Protection Using a Live Attenuated African Swine Fever Virus Model

    Science.gov (United States)

    Carlson, Jolene; O’Donnell, Vivian; Alfano, Marialexia; Velazquez Salinas, Lauro; Holinka, Lauren G.; Krug, Peter W.; Gladue, Douglas P.; Higgs, Stephen; Borca, Manuel V.

    2016-01-01

    African swine fever (ASF) is a lethal hemorrhagic disease of swine caused by a double-stranded DNA virus, ASF virus (ASFV). There is no vaccine to prevent the disease and current control measures are limited to culling and restricting animal movement. Swine infected with attenuated strains are protected against challenge with a homologous virulent virus, but there is limited knowledge of the host immune mechanisms generating that protection. Swine infected with Pretoriuskop/96/4 (Pret4) virus develop a fatal severe disease, while a derivative strain lacking virulence-associated gene 9GL (Pret4Δ9GL virus) is completely attenuated. Swine infected with Pret4Δ9GL virus and challenged with the virulent parental virus at 7, 10, 14, 21, and 28 days post infection (dpi) showed a progressive acquisition of protection (from 40% at 7 dpi to 80% at 21 and 28 dpi). This animal model was used to associate the presence of host immune response (ASFV-specific antibody and interferon (IFN)-γ responses, or specific cytokine profiles) and protection against challenge. With the exception of ASFV-specific antibodies in survivors challenged at 21 and 28 dpi, no association between the parameters assessed and protection could be established. These results, encompassing data from 65 immunized swine, underscore the complexity of the system under study, suggesting that protection relies on the concurrence of different host immune mechanisms. PMID:27782090

  20. Association of the Host Immune Response with Protection Using a Live Attenuated African Swine Fever Virus Model

    Directory of Open Access Journals (Sweden)

    Jolene Carlson

    2016-10-01

    Full Text Available African swine fever (ASF is a lethal hemorrhagic disease of swine caused by a double-stranded DNA virus, ASF virus (ASFV. There is no vaccine to prevent the disease and current control measures are limited to culling and restricting animal movement. Swine infected with attenuated strains are protected against challenge with a homologous virulent virus, but there is limited knowledge of the host immune mechanisms generating that protection. Swine infected with Pretoriuskop/96/4 (Pret4 virus develop a fatal severe disease, while a derivative strain lacking virulence-associated gene 9GL (Pret4Δ9GL virus is completely attenuated. Swine infected with Pret4Δ9GL virus and challenged with the virulent parental virus at 7, 10, 14, 21, and 28 days post infection (dpi showed a progressive acquisition of protection (from 40% at 7 dpi to 80% at 21 and 28 dpi. This animal model was used to associate the presence of host immune response (ASFV-specific antibody and interferon (IFN-γ responses, or specific cytokine profiles and protection against challenge. With the exception of ASFV-specific antibodies in survivors challenged at 21 and 28 dpi, no association between the parameters assessed and protection could be established. These results, encompassing data from 65 immunized swine, underscore the complexity of the system under study, suggesting that protection relies on the concurrence of different host immune mechanisms.

  1. The yellow fever 17D vaccine virus: molecular basis of viral attenuation and its use as an expression vector

    Directory of Open Access Journals (Sweden)

    Galler R.

    1997-01-01

    Full Text Available The yellow fever (YF virus is the prototype flavivirus. The use of molecular techniques has unraveled the basic mechanisms of viral genome structure and expression. Recent trends in flavivirus research include the use of infectious clone technology with which it is possible to recover virus from cloned cDNA. Using this technique, mutations can be introduced at any point of the viral genome and their resulting effect on virus phenotype can be assessed. This approach has opened new possibilities to study several biological viral features with special emphasis on the issue of virulence/attenuation of the YF virus. The feasibility of using YF virus 17D vaccine strain, for which infectious cDNA is available, as a vector for the expression of heterologous antigens is reviewed

  2. African Green Monkeys Recapitulate the Clinical Experience with Replication of Live Attenuated Pandemic Influenza Virus Vaccine Candidates

    Science.gov (United States)

    Matsuoka, Yumiko; Suguitan, Amorsolo; Orandle, Marlene; Paskel, Myeisha; Boonnak, Kobporn; Gardner, Donald J.; Feldmann, Friederike; Feldmann, Heinz; Marino, Michael; Jin, Hong; Kemble, George

    2014-01-01

    ABSTRACT Live attenuated cold-adapted (ca) H5N1, H7N3, H6N1, and H9N2 influenza vaccine viruses replicated in the respiratory tract of mice and ferrets, and 2 doses of vaccines were immunogenic and protected these animals from challenge infection with homologous and heterologous wild-type (wt) viruses of the corresponding subtypes. However, when these vaccine candidates were evaluated in phase I clinical trials, there were inconsistencies between the observations in animal models and in humans. The vaccine viruses did not replicate well and immune responses were variable in humans, even though the study subjects were seronegative with respect to the vaccine viruses before vaccination. Therefore, we sought a model that would better reflect the findings in humans and evaluated African green monkeys (AGMs) as a nonhuman primate model. The distribution of sialic acid (SA) receptors in the respiratory tract of AGMs was similar to that in humans. We evaluated the replication of wt and ca viruses of avian influenza (AI) virus subtypes H5N1, H6N1, H7N3, and H9N2 in the respiratory tract of AGMs. All of the wt viruses replicated efficiently, while replication of the ca vaccine viruses was restricted to the upper respiratory tract. Interestingly, the patterns and sites of virus replication differed among the different subtypes. We also evaluated the immunogenicity and protective efficacy of H5N1, H6N1, H7N3, and H9N2 ca vaccines. Protection from wt virus challenge correlated well with the level of serum neutralizing antibodies. Immune responses were slightly better when vaccine was delivered by both intranasal and intratracheal delivery than when it was delivered intranasally by sprayer. We conclude that live attenuated pandemic influenza virus vaccines replicate similarly in AGMs and human subjects and that AGMs may be a useful model to evaluate the replication of ca vaccine candidates. IMPORTANCE Ferrets and mice are commonly used for preclinical evaluation of influenza

  3. Riboswitch-mediated Attenuation of Transgene Cytotoxicity Increases Adeno-associated Virus Vector Yields in HEK-293 Cells.

    Science.gov (United States)

    Strobel, Benjamin; Klauser, Benedikt; Hartig, Jörg S; Lamla, Thorsten; Gantner, Florian; Kreuz, Sebastian

    2015-10-01

    Cytotoxicity of transgenes carried by adeno-associated virus (AAV) vectors might be desired, for instance, in oncolytic virotherapy or occur unexpectedly in exploratory research when studying sparsely characterized genes. To date, most AAV-based studies use constitutively active promoters (e.g., the CMV promoter) to drive transgene expression, which often hampers efficient AAV production due to cytotoxic, antiproliferative, or unknown transgene effects interfering with producer cell performance. Therefore, we explored artificial riboswitches as novel tools to control transgene expression during AAV production in mammalian cells. Our results demonstrate that the guanine-responsive GuaM8HDV aptazyme efficiently attenuates transgene expression and associated detrimental effects, thereby boosting AAV vector yields up to 23-fold after a single addition of guanine. Importantly, riboswitch-harboring vectors preserved their ability to express functional transgene at high levels in the absence of ligand, as demonstrated in a mouse model of AAV-TGFβ1-induced pulmonary fibrosis. Thus, our study provides the first application-ready biotechnological system-based on aptazymes, which should enable high viral vector yields largely independent of the transgene used. Moreover, the RNA-intrinsic, small-molecule regulatable mode of action of riboswitches provides key advantages over conventional transcription factor-based regulatory systems. Therefore, such riboswitch vectors might be ultimately applied to temporally control therapeutic transgene expression in vivo.

  4. Transcription of minute virus of mice, an autonomous parvovirus, may be regulated by attenuation

    Energy Technology Data Exchange (ETDEWEB)

    Ben-Asher, E.; Aloni, Y.

    1984-10-01

    To characterize the transcriptional organization and regulation of minute virus of mice, an autonomous parvovirus, viral transcriptional complexes were isolated and cleaved with restriction enzymes. The in vivo preinitiated nascent RNA was elongated in vitro in the presence of (alpha-/sup 32/P)UTP to generate runoff transcripts. The lengths of the runoff transcripts were analyzed by gel electrophoresis under denaturing conditions. On the basis of the map locations of the restriction sites and the lengths of the runoff transcripts, the in vivo initiation sites were determined. Two major initiation sites having similar activities were thus identified at residues 201 +/- 5 and 2005 +/- 5; both of them were preceded by a TATAA sequence. When uncleaved viral transcriptional complexes or isolated nuclei were incubated in vitro in the presence of (alpha-/sup 32/P)UTP or (alpha-/sup 32/P)CTP, they synthesized labeled RNA that, as determined by polyacrylamide gel electrophoresis, contained a major band of 142 nucleotides. The RNA of the major band was mapped between the initiation site at residue 201 +/- 5 and residue 342. We noticed the potential of forming two mutually exclusive stem-and-loop structures in the 142-nucleotide RNA; one of them is followed by a string of uridylic acid residues typical of a procaryotic transcription termination signal. We propose that, as in the transcription of simian virus 40, RNA transcription in minute virus of mice may be regulated by attenuation and may involve eucaryotic polymerase B, which can respond to a transcription termination signal similar to that of the procaryotic polymerase.

  5. Deletion of virulence associated genes from attenuated African swine fever virus isolate OUR T88/3 decreases its ability to protect against challenge with virulent virus.

    Science.gov (United States)

    Abrams, Charles C; Goatley, Lynnette; Fishbourne, Emma; Chapman, David; Cooke, Lyndsay; Oura, Christopher A; Netherton, Christopher L; Takamatsu, Haru-Hisa; Dixon, Linda K

    2013-08-15

    African swine fever virus (ASFV) causes an acute haemorrhagic disease of domestic pigs against which there is no effective vaccine. The attenuated ASFV strain OUR T88/3 has been shown previously to protect vaccinated pigs against challenge with some virulent strains including OUR T88/1. Two genes, DP71L and DP96R were deleted from the OUR T88/3 genome to create recombinant virus OUR T88/3ΔDP2. Deletion of these genes from virulent viruses has previously been shown to reduce ASFV virulence in domestic pigs. Groups of 6 pigs were immunised with deletion virus OUR T88/3ΔDP2 or parental virus OUR T88/3 and challenged with virulent OUR T88/1 virus. Four pigs (66%) were protected by inoculation with the deletion virus OUR T88/3ΔDP2 compared to 100% protection with the parental virus OUR T88/3. Thus the deletion of the two genes DP71L and DP96R from OUR T88/3 strain reduced its ability to protect pigs against challenge with virulent virus.

  6. Pre- and post-exposure safety and efficacy of attenuated rabies virus vaccines are enhanced by their expression of IFNγ

    Energy Technology Data Exchange (ETDEWEB)

    Barkhouse, Darryll A. [Department of Cancer Biology, 1020 Locust St., Jefferson Alumni Hall, Room 454, Philadelphia, PA 19107 (United States); Center for Neurovirology 1020 Locust St., Jefferson Alumni Hall, Room 454, Philadelphia, PA 19107 (United States); Faber, Milosz [Center for Neurovirology 1020 Locust St., Jefferson Alumni Hall, Room 454, Philadelphia, PA 19107 (United States); Department of Microbiology and Immunology 1020 Locust St., Jefferson Alumni Hall, Room 465, Philadelphia, PA 19107 (United States); Hooper, D. Craig, E-mail: douglas.hooper@jefferson.edu [Department of Cancer Biology, 1020 Locust St., Jefferson Alumni Hall, Room 454, Philadelphia, PA 19107 (United States); Department of Neurological Surgery, 1020 Locust St., Jefferson Alumni Hall, Room 454, Philadelphia, PA 19107 (United States); Center for Neurovirology 1020 Locust St., Jefferson Alumni Hall, Room 454, Philadelphia, PA 19107 (United States)

    2015-01-01

    Consistent with evidence of a strong correlation between interferon gamma (IFNγ) production and rabies virus (RABV) clearance from the CNS, we recently demonstrated that engineering a pathogenic RABV to express IFNγ highly attenuates the virus. Reasoning that IFNγ expression by RABV vaccines would enhance their safety and efficacy, we reverse-engineered two proven vaccine vectors, GAS and GASGAS, to express murine IFNγ. Mortality and morbidity were monitored during suckling mice infection, immunize/challenge experiments and mixed intracranial infections. We demonstrate that GASγ and GASγGAS are significantly attenuated in suckling mice compared to the GASGAS vaccine. GASγ better protects mice from lethal DRV4 RABV infection in both pre- and post-exposure experiments compared to GASGAS. Finally, GASγGAS reduces post-infection neurological sequelae, compared to control, during mixed intracranial infection with DRV4. These data show IFNγ expression by a vaccine vector can enhance its safety while increasing its efficacy as pre- and post-exposure treatment. - Highlights: • IFNγ expression improves attenuated rabies virus safety and immunogenicity. • IFNγ expression is safer and more immunogenic than doubling glycoprotein expression. • Co-infection with IFNγ-expressing RABV prevents wild-type rabies virus lethality. • Vaccine safety and efficacy is additive for IFNγ and double glycoprotein expression.

  7. Computer-aided codon-pairs deoptimization of the major envelope GP5 gene attenuates porcine reproductive and respiratory syndrome virus.

    Science.gov (United States)

    Ni, Yan-Yan; Zhao, Zhao; Opriessnig, Tanja; Subramaniam, Sakthivel; Zhou, Lei; Cao, Dianjun; Cao, Qian; Yang, Hanchun; Meng, Xiang-Jin

    2014-02-01

    Synthetic attenuated virus engineering (SAVE) is an emerging technology that enables rapid attenuation of viruses. In this study, by using SAVE we demonstrated rapid attenuation of an arterivirus, porcine reproductive and respiratory syndrome virus (PRRSV). The major envelope GP5 gene of PRRSV was codon-pair deoptimized aided by a computer algorithm. The codon-pair deoptimized virus, designated as SAVE5 with a deoptimized GP5 gene, was successfully rescued in vitro. The SAVE5 virus replicated at a lower level in vitro with a significant decrease of GP5 protein expression compared to the wild-type PRRSV VR2385 virus. Pigs experimentally infected with the SAVE5 virus had significantly lower viremia level up to 14 days post-infection as well as significantly reduced gross and histological lung lesions when compared to wild-type PRRSV VR2385 virus-infected pigs, indicating the attenuation of the SAVE5 virus. This study proved the feasibility of rapidly attenuating PRRSV by SAVE.

  8. Hepatitis B virus disrupts mitochondrial dynamics: induces fission and mitophagy to attenuate apoptosis.

    Directory of Open Access Journals (Sweden)

    Seong-Jun Kim

    Full Text Available Human hepatitis B virus (HBV causes chronic hepatitis and is associated with the development of hepatocellular carcinoma. HBV infection alters mitochondrial metabolism. The selective removal of damaged mitochondria is essential for the maintenance of mitochondrial and cellular homeostasis. Here, we report that HBV shifts the balance of mitochondrial dynamics toward fission and mitophagy to attenuate the virus-induced apoptosis. HBV induced perinuclear clustering of mitochondria and triggered mitochondrial translocation of the dynamin-related protein (Drp1 by stimulating its phosphorylation at Ser616, leading to mitochondrial fission. HBV also stimulated the gene expression of Parkin, PINK1, and LC3B and induced Parkin recruitment to the mitochondria. Upon translocation to mitochondria, Parkin, an E3 ubiquitin ligase, underwent self-ubiquitination and facilitated the ubiquitination and degradation of its substrate Mitofusin 2 (Mfn2, a mediator of mitochondrial fusion. In addition to conventional immunofluorescence, a sensitive dual fluorescence reporter expressing mito-mRFP-EGFP fused in-frame to a mitochondrial targeting sequence was employed to observe the completion of the mitophagic process by delivery of the engulfed mitochondria to lysosomes for degradation. Furthermore, we demonstrate that viral HBx protein plays a central role in promoting aberrant mitochondrial dynamics either when expressed alone or in the context of viral genome. Perturbing mitophagy by silencing Parkin led to enhanced apoptotic signaling, suggesting that HBV-induced mitochondrial fission and mitophagy promote cell survival and possibly viral persistence. Altered mitochondrial dynamics associated with HBV infection may contribute to mitochondrial injury and liver disease pathogenesis.

  9. Protection of SA14-14-2 live attenuated Japanese encephalitis vaccine against the wild-type JE viruses

    Institute of Scientific and Technical Information of China (English)

    贾丽丽; 王志伟; 俞永新

    2003-01-01

    ObjectiveTo explore on the immunity of live attenuated Japanese Encephalitis (JE) vaccine(SA14-14-2) to different wild JE virus (JEV) strains. MethodsThe neutralizing effect of the vaccine against different wild JE virus strains was detected by plaque reduction neutralization test (PRNT), and the immunogenicity was studied on mice by vaccination -challenge protection test. In the PRNT , pooled sera from vaccinated human were tested against 10 strains of JEV , one isolated in Taiwan and 9 from other Asian countries.In the vaccination challenge test, mice received one dose of the live vaccine subcutaneously and were challenged intraperitoneally 14 days later against 22 JEV virus strains, 11 were isolated in China and the other 11 from Tailand, Vietnahailam, Indonesia, India, Philippines and Japan. ResultsThe protection rates to all the 22 challenge virus were 90%-100% when 340 PFU/0.1 ml vaccinate virus was administered. The neutralizing effect showed that all the JEV isolates many have neutralized by the sera. ConclusionSA14-14-2 live attenuated prepared with strain SA14-14-2 is broadly immunogenic and may have effective protection against in Asian JE affected countries.

  10. Nasal lavage natural killer cell function is suppressed in smokers after live attenuated influenza virus

    Directory of Open Access Journals (Sweden)

    Zhou Haibo

    2011-08-01

    Full Text Available Abstract Background Modified function of immune cells in nasal secretions may play a role in the enhanced susceptibility to respiratory viruses that is seen in smokers. Innate immune cells in nasal secretions have largely been characterized by cellular differentials using morphologic criteria alone, which have successfully identified neutrophils as a significant cell population within nasal lavage fluid (NLF cells. However, flow cytometry may be a superior method to fully characterize NLF immune cells. We therefore characterized immune cells in NLF by flow cytometry, determined the effects of live attenuated influenza virus (LAIV on NLF and peripheral blood immune cells, and compared responses in samples obtained from smokers and nonsmokers. Methods In a prospective observational study, we characterized immune cells in NLF of nonsmokers at baseline using flow cytometry and immunohistochemistry. Nonsmokers and smokers were inoculated with LAIV on day 0 and serial nasal lavages were collected on days 1-4 and day 9 post-LAIV. LAIV-induced changes of NLF cells were characterized using flow cytometry. Cell-free NLF was analyzed for immune mediators by bioassay. Peripheral blood natural killer (NK cells from nonsmokers and smokers at baseline were stimulated in vitro with LAIV followed by flow cytometric and mediator analyses. Results CD45(+CD56(-CD16(+ neutrophils and CD45(+CD56(+ NK cells comprised median 4.62% (range 0.33-14.52 and 23.27% (18.29-33.97, respectively, of non-squamous NLF cells in nonsmokers at baseline. LAIV did not induce changes in total NK cell or neutrophil percentages in either nonsmokers or smokers. Following LAIV inoculation, CD16(+ NK cell percentages and granzyme B levels increased in nonsmokers, and these effects were suppressed in smokers. LAIV inoculation enhanced expression of activating receptor NKG2D and chemokine receptor CXCR3 on peripheral blood NK cells from both nonsmokers and smokers in vitro but did not induce

  11. TRIM5α Promotes Ubiquitination of Rta from Epstein–Barr Virus to Attenuate Lytic Progression

    Science.gov (United States)

    Huang, Hsiang-Hung; Chen, Chien-Sin; Wang, Wen-Hung; Hsu, Shih-Wei; Tsai, Hsiao-Han; Liu, Shih-Tung; Chang, Li-Kwan

    2017-01-01

    Replication and transcription activator (Rta), a key protein expressed by Epstein–Barr virus (EBV) during the immediate-early stage of the lytic cycle, is responsible for the activation of viral lytic genes. In this study, GST-pulldown and coimmunoprecipitation assays showed that Rta interacts in vitro and in vivo with TRIM5α, a host factor known to be involved in the restriction of retroviral infections. Confocal microscopy results revealed that Rta colocalizes with TRIM5α in the nucleus during lytic progression. The interaction involves 190 amino acids in the N-terminal of Rta and the RING domain in TRIM5α, and it was further found that TRIM5α acts as an E3 ubiquitin ligase to promote Rta ubiquitination. Overexpression of TRIM5α reduced the transactivating capabilities of Rta, while reducing TRIM5α expression enhanced EBV lytic protein expression and DNA replication. Taken together, these results point to a critical role for TRIM5α in attenuating EBV lytic progression through the targeting of Rta for ubiquitination, and suggest that the restrictive capabilities of TRIM5α may go beyond retroviral infections. PMID:28105027

  12. Temperature-sensitive mutations for live-attenuated Rift Valley fever vaccines: Implications from other RNA viruses

    Directory of Open Access Journals (Sweden)

    Shoko eNishiyama

    2015-08-01

    Full Text Available Rift Valley fever (RVF is a mosquito-borne zoonotic disease endemic to the African continent. RVF is characterized by high rate of abortions in ruminants and hemorrhagic fever, encephalitis or blindness in humans. RVF is caused by the Rift Valley fever virus (RVFV: genus Phlebovirus, family Bunyaviridae. Vaccination is the only known effective strategy to prevent the disease, but there are no licensed RVF vaccines available for humans. A live-attenuated vaccine candidate derived from the wild-type pathogenic Egyptian ZH548 strain, MP-12, has been conditionally licensed for veterinary use in the United States. MP-12 displays a temperature-sensitive (ts phenotype and does not replicate at 41oC. The ts mutation limits viral replication at a specific body temperature and may lead to an attenuation of the virus. Here we will review well-characterized ts mutations for RNA viruses, and further discuss the potential in designing novel live-attenuated vaccines for RVF.

  13. Rescue of avian leukosis subgroup-J-associated acutely transforming viruses carrying different lengths of the v-fps oncogene and analysis of their tumorigenicity.

    Science.gov (United States)

    Wang, Yixin; Fang, Lichun; Li, Jianliang; Li, Yang; Cui, Shuai; Sun, Xiaolong; Chang, Shuang; Zhao, Peng; Cui, Zhizhong

    2016-12-01

    In our previous study, six subgroup J strains of avian leukosis virus (ALV-J)-associated acutely transforming viruses carrying different lengths of the v-fps oncogene, designated as Fu-J and Fu-J1-5, were isolated and characterized from fibrosarcomas in ALV-J-infected chickens. In the present study, the oncogenic potential of Fu-J and Fu-J1-5 was investigated using a reverse genetics technique. Six replication-defective viruses, named rFu-J and rFu-J1-5, were rescued with the replication-competent rescued ALV-J strain rSDAU1005 as a helper virus by co-transfection of chicken embryo fibroblast monolayers with infectious clone plasmids. Experimental bird studies were performed, demonstrating that only the rescued rFu-J virus carrying the complete v-fps oncogene with rSDAU1005 as the helper virus could induce acute fibrosarcoma after inoculation in specific-pathogen-free (SPF) chickens. These results provide direct evidence that the replication-defective acutely transforming Fu-J virus, with the complete v-fps oncogene, was associated with acute fibrosarcoma in chickens infected with ALV-J in the field, as reported previously.

  14. Suppressing active replication of a live attenuated simian immunodeficiency virus vaccine does not abrogate protection from challenge

    Energy Technology Data Exchange (ETDEWEB)

    Gabriel, Benjamin; Fiebig, Uwe; Hohn, Oliver [Robert Koch-Institut, Berlin (Germany); Plesker, Roland; Coulibaly, Cheick; Cichutek, Klaus; Mühlebach, Michael D. [Paul-Ehrlich-Institut, Langen (Germany); Bannert, Norbert; Kurth, Reinhard [Robert Koch-Institut, Berlin (Germany); Norley, Stephen, E-mail: NorleyS@rki.de [Robert Koch-Institut, Berlin (Germany)

    2016-02-15

    Although safety concerns preclude the use of live attenuated HIV vaccines in humans, they provide a useful system for identifying the elusive correlates of protective immunity in the SIV/macaque animal model. However, a number of pieces of evidence suggest that protection may result from prior occupancy of susceptible target cells by the vaccine virus rather than the immune response. To address this, we developed a Nef-deletion variant of an RT-SHIV whose active replication could be shut off by treatment with RT-inhibitors. Groups of macaques were inoculated with the ∆Nef-RT-SHIV and immune responses allowed to develop before antiretroviral treatment and subsequent challenge with wild-type SIVmac239. Vaccinated animals either resisted infection fully or significantly controlled the subsequent viremia. However, there was no difference between animals undergoing replication of the vaccine virus and those without. This strongly suggests that competition for available target cells does not play a role in protection. - Highlights: • A Nef-deleted RT-SHIV was used as a live attenuated vaccine in macaques. • Vaccine virus replication was shut down to investigate its role in protection. • Ongoing vaccine virus replication did not appear to be necessary for protection. • An analysis of T- and B-cell responses failed to identify a correlate of protection.

  15. A novel, live-attenuated vesicular stomatitis virus vector displaying conformationally intact, functional HIV-1 envelope trimers that elicits potent cellular and humoral responses in mice.

    Directory of Open Access Journals (Sweden)

    Svetlana Rabinovich

    Full Text Available Though vaccination with live-attenuated SIV provides the greatest protection from progressive disease caused by SIV challenge in rhesus macaques, attenuated HIV presents safety concerns as a vaccine; therefore, live viral vectors carrying HIV immunogens must be considered. We have designed a replication-competent vesicular stomatitis virus (VSV displaying immunogenic HIV-1 Env trimers and attenuating quantities of the native surface glycoprotein (G. The clade B Env immunogen is an Env-VSV G hybrid (EnvG in which the transmembrane and cytoplasmic tail regions are derived from G. Relocation of the G gene to the 5'terminus of the genome and insertion of EnvG into the natural G position induced a ∼1 log reduction in surface G, significant growth attenuation compared to wild-type, and incorporation of abundant EnvG. Western blot analysis indicated that ∼75% of incorporated EnvG was a mature proteolytically processed form. Flow cytometry showed that surface EnvG bound various conformationally- and trimer-specific antibodies (Abs, and in-vitro growth assays on CD4+CCR5+ cells demonstrated EnvG functionality. Neither intranasal (IN or intramuscular (IM administration in mice induced any observable pathology and all regimens tested generated potent Env-specific ELISA titers of 10(4-10(5, with an IM VSV prime/IN VSV boost regimen eliciting the highest binding and neutralizing Ab titers. Significant quantities of Env-specific CD4+ T cells were also detected, which were augmented as much as 70-fold by priming with IM electroporated plasmids encoding EnvG and IL-12. These data suggest that our novel vector can achieve balanced safety and immunogenicity and should be considered as an HIV vaccine platform.

  16. Genomic Changes in an Attenuated ZB Strain of Foot-and-Mouth Disease Virus Serotype Asia1 and Comparison with Its Virulent Parental Strain

    Directory of Open Access Journals (Sweden)

    Aiguo Xin

    2014-01-01

    Full Text Available The molecular basis of attenuation of foot-and-mouth disease virus (FMDV serotype Asia1 ZB strain remains unknown. To understand the genetic changes of attenuation, we compared the entire genomes of three different rabbit-passaged attenuated ZB strains (ZB/CHA/58(att, ZBRF168, and ZBRF188 and their virulent parental strains (ZBCF22 and YNBS/58. The results showed that attenuation may be brought about by 28 common amino acid substitutions in the coding region, with one nucleotide point mutation in the 5′-untranslated region (5′-UTR and another one in the 3′-UTR. In addition, a total of 21 nucleotides silent mutations had been found after attenuation. These substitutions, alone or in combination, may be responsible for the attenuated phenotype of the ZB strain in cattle. This will contribute to elucidation of attenuating molecular basis of the FMDV ZB strain.

  17. Evaluation of the Efficacy, Potential for Vector Transmission, and Duration of Immunity of MP-12, an Attenuated Rift Valley Fever Virus Vaccine Candidate, in Sheep

    Science.gov (United States)

    2015-08-01

    and L (24–26), thus significantly reducing the risk of reversion to viru - lence that might otherwise arise from a recombination event with other viruses ...Transmission, and Duration of Immunity of MP-12, an Attenuated Rift Valley Fever Virus Vaccine Candidate, in Sheep 5a. CONTRACT NUMBER 5b. GRANT...Immunol. 2015; 22(8):930-937 14. ABSTRACT Rift Valley fever virus (RVFV) causes serious disease in ruminants and humans in Africa. In North America

  18. Limited potential for mosquito transmission of genetically engineered, live-attenuated western equine encephalitis virus vaccine candidates.

    Science.gov (United States)

    Turell, Michael J; O'Guinn, Monica L; Parker, Michael D

    2003-02-01

    Specific mutations associated with attenuation of Venezuelan equine encephalitis (VEE) virus in rodent models were identified during efforts to develop an improved VEE vaccine. Analogous mutations were produced in full-length cDNA clones of the Cba 87 strain of western equine encephalitis (WEE) virus by site-directed mutagenesis in an attempt to develop an improved WEE vaccine. Isogenic viral strains with these mutations were recovered after transfection of baby hamster kidney cells with infectious RNA. We evaluated two of these strains (WE2102 and WE2130) for their ability to replicate in and be transmitted by Culex tarsalis, the principal natural vector of WEE virus in the United States. Each of the vaccine candidates contained a deletion of the PE2 furin cleavage site and a secondary mutation in the E1 or E2 glycoprotein. Both of these potential candidates replicated in mosquitoes significantly less efficiently than did either wild-type WEE (Cba 87) virus or the parental clone (WE2000). Likewise, after intrathoracic inoculation, mosquitoes transmitted the vaccine candidate strains significantly less efficiently than they transmitted either the wild-type or the parental clone. One-day-old chickens vaccinated with either of the two vaccine candidates did not become viremic when challenged with virulent WEE virus two weeks later. Mutations that result in less efficient replication in or transmission by mosquitoes should enhance vaccine safety and reduce the possibility of accidental introduction of the vaccine strain to unintentional hosts.

  19. Live attenuated African swine fever viruses as ideal tools to dissect the mechanisms involved in viral pathogenesis and immune protection.

    Science.gov (United States)

    Lacasta, Anna; Monteagudo, Paula L; Jiménez-Marín, Ángeles; Accensi, Francesc; Ballester, María; Argilaguet, Jordi; Galindo-Cardiel, Iván; Segalés, Joaquim; Salas, María L; Domínguez, Javier; Moreno, Ángela; Garrido, Juan J; Rodríguez, Fernando

    2015-11-20

    African swine fever virus (ASFV) is the causal agent of African swine fever, a hemorrhagic and often lethal porcine disease causing enormous economical losses in affected countries. Endemic for decades in most of the sub-Saharan countries and Sardinia, the risk of ASFV-endemicity in Europe has increased since its last introduction into Europe in 2007. Live attenuated viruses have been demonstrated to induce very efficient protective immune responses, albeit most of the time protection was circumscribed to homologous ASFV challenges. However, their use in the field is still far from a reality, mainly due to safety concerns. In this study we compared the course of the in vivo infection caused by two homologous ASFV strains: the virulent E75 and the cell cultured adapted strain E75CV1, obtained from adapting E75 to grow in the CV1 cell-line. Interestingly, the kinetics of both viruses not only differed on the clinical signs that they caused and in the virus loads found, but also in the immunological pathways activated throughout the infections. Furthermore, E75CV1 confirmed its protective potential against the homologous E75 virus challenge and allowed the demonstration of poor cross-protection against BA71, thus defining it as heterologous. The in vitro specificity of the CD8(+) T-cells present at the time of lethal challenge showed a clear activation against the homologous virus (E75) but not against BA71. These findings will be of utility for a better understanding of ASFV pathogenesis and for the rational designing of safe and efficient vaccines against this virus.

  20. Live Cell Analysis and Mathematical Modeling Identify Determinants of Attenuation of Dengue Virus 2'-O-Methylation Mutant.

    Directory of Open Access Journals (Sweden)

    Bianca Schmid

    2015-12-01

    Full Text Available Dengue virus (DENV is the most common mosquito-transmitted virus infecting ~390 million people worldwide. In spite of this high medical relevance, neither a vaccine nor antiviral therapy is currently available. DENV elicits a strong interferon (IFN response in infected cells, but at the same time actively counteracts IFN production and signaling. Although the kinetics of activation of this innate antiviral defense and the timing of viral counteraction critically determine the magnitude of infection and thus disease, quantitative and kinetic analyses are lacking and it remains poorly understood how DENV spreads in IFN-competent cell systems. To dissect the dynamics of replication versus antiviral defense at the single cell level, we generated a fully viable reporter DENV and host cells with authentic reporters for IFN-stimulated antiviral genes. We find that IFN controls DENV infection in a kinetically determined manner that at the single cell level is highly heterogeneous and stochastic. Even at high-dose, IFN does not fully protect all cells in the culture and, therefore, viral spread occurs even in the face of antiviral protection of naïve cells by IFN. By contrast, a vaccine candidate DENV mutant, which lacks 2'-O-methylation of viral RNA is profoundly attenuated in IFN-competent cells. Through mathematical modeling of time-resolved data and validation experiments we show that the primary determinant for attenuation is the accelerated kinetics of IFN production. This rapid induction triggered by mutant DENV precedes establishment of IFN-resistance in infected cells, thus causing a massive reduction of virus production rate. In contrast, accelerated protection of naïve cells by paracrine IFN action has negligible impact. In conclusion, these results show that attenuation of the 2'-O-methylation DENV mutant is primarily determined by kinetics of autocrine IFN action on infected cells.

  1. The immunizing effect and reactogenicity of two live attenuated mumps virus vaccines in Swedish schoolchildren.

    Science.gov (United States)

    Christenson, B; Heller, L; Böttiger, M

    1983-10-01

    An evaluation of the seroconversion and booster effects after vaccination with two different mumps vaccines, the Urabe Am 9 strain and the Jeryl Lynn strain, was carried out in schoolchildren. Four hundred and fifty-four schoolchildren aged 11 to 12 years with no previous history of mumps or mumps vaccination were enrolled for the study. The antibody responses were measured by serum neutralization (SN) and haemolysis-in-gel (HIG) tests. Of the 454 subjects, 130 were found to be initially seronegative. Two lots of different strengths of each vaccine were used to evaluate the relationships. The Urabe Am 9 vaccine lots had infectivity titres of 100 000 and 19 000 TCID50 per dose and the Jeryl Lynn vaccine titres of 59 000 and 28 000 TCID50 per dose. Only slight differences in seroconversion rates were seen between the lots. The overall seroconversion rate, measured by SN, was 94% for the Urabe Am 9 vaccine and 91% for the Jeryl Lynn vaccine, whereas the geometric mean titre for virus-neutralizing antibody in seroconverting children was 7.4 with the Urabe Am 9 vaccine and 10.7 with the Jeryl Lynn vaccine. In children who were seropositive prior to vaccination, a marked rise in antibody titre was found 8 weeks after vaccine injection indicating a booster effect. The miscellaneous post-vaccination side-effects were mild and inconsequential.

  2. Immunogenicity and protective efficacy of an elastase-dependent live attenuated swine influenza virus vaccine administered intranasally in pigs.

    Science.gov (United States)

    Masic, Aleksandar; Lu, Xinya; Li, Junwei; Mutwiri, George K; Babiuk, Lorne A; Brown, Earl G; Zhou, Yan

    2010-10-01

    Influenza A virus is an important respiratory pathogen of swine that causes significant morbidity and economic impact on the swine industry. Vaccination is the first choice for prevention and control of influenza infections. Live attenuated influenza vaccines (LAIV) are approved for use in humans and horses and their application provides broad protective immunity, however no LAIV against swine influenza virus (SIV) exists in the market. Previously we reported that an elastase-dependent mutant SIV A/Sw/Sk-R345V (R345V) derived from A/Sw/Saskatchewan/18789/02 (H1N1) (SIV/Sk02) is highly attenuated in pigs. Two intratracheal administrations of R345V induced strong cell-mediated and humoral immune responses and provided a high degree of protection to antigenically different SIV infection in pigs. Here we evaluated the immunogenicity and the protective efficacy of R345V against SIV infection by intranasal administration, the more practical route for vaccination of pigs in the field. Our data showed that intranasally administered R345V live vaccine is capable of inducing strong antigen-specific IFN-γ response from local tracheo-bronchial lymphocytes and antibody responses in serum and respiratory mucosa after two applications. Intranasal vaccination of R345V provided pigs with complete protection not only from parental wild type virus infection, but also from homologous antigenic variant A/Sw/Indiana/1726/88 (H1N1) infection. Moreover, intranasal administration of R345V conferred partial protection from heterologous subtypic H3N2 SIV infection in pigs. Thus, R345V elastase-dependent mutant SIV can serve as a live vaccine against antigenically different swine influenza viruses in pigs.

  3. Deletion of the thymidine kinase gene induces complete attenuation of the Georgia isolate of African swine fever virus.

    Science.gov (United States)

    Sanford, B; Holinka, L G; O'Donnell, V; Krug, P W; Carlson, J; Alfano, M; Carrillo, C; Wu, Ping; Lowe, Andre; Risatti, G R; Gladue, D P; Borca, M V

    2016-02-02

    African swine fever virus (ASFV) is the etiological agent of a contagious and often lethal viral disease of domestic pigs. There are no vaccines to control Africa swine fever (ASF). Experimental vaccines have been developed using genetically modified live attenuated ASFVs obtained by specifically deleting virus genes involved in virulence, including the thymidine kinase (TK) gene. TK has been shown to be involved in the virulence of several viruses, including ASFV. Here we report the construction of a recombinant virus (ASFV-G/V-ΔTK) obtained by deleting the TK gene in a virulent strain of ASFV Georgia adapted to replicate in Vero cells (ASFV-G/VP30). ASFV-G/P-ΔTK demonstrated decreased replication both in primary swine macrophage cell cultures and in Vero cells compared with ASFV-G/VP30. In vivo, intramuscular administration of up to 10(6) TCID50 of ASFV-G/V-ΔTK does not result in ASF disease. However, these animals are not protected when challenged with the virulent parental Georgia strain.

  4. Effect of broccoli sprouts on nasal response to live attenuated influenza virus in smokers: a randomized, double-blind study.

    Directory of Open Access Journals (Sweden)

    Terry L Noah

    Full Text Available Smokers have increased susceptibility and altered innate host defense responses to influenza virus infection. Broccoli sprouts are a source of the Nrf2 activating agentsulforaphane, and short term ingestion of broccoli sprout homogenates (BSH has been shown to reduce nasal inflammatory responses to oxidant pollutants.Assess the effects of BSH on nasal cytokines, virus replication, and Nrf2-dependent enzyme expression in smokers and nonsmokers.We conducted a randomized, double-blind, placebo-controlled trial comparing the effects of BSH on serially sampled nasal lavage fluid (NLF cytokines, viral sequence quantity, and Nrf2-dependent enzyme expression in NLF cells and biopsied epithelium. Healthy young adult smokers and nonsmokers ingested BSH or placebo (alfalfa sprout homogenate for 4 days, designated Days -1, 0, 1, 2. On Day 0 they received standard vaccine dose of live attenuated influenza virus (LAIV intranasally. Nasal lavage fluids and nasal biopsies were collected serially to assess response to LAIV.In area under curve analyses, post-LAIV IL-6 responses (P = 0.03 and influenza sequences (P = 0.01 were significantly reduced in NLF from BSH-treated smokers, whilequinoneoxidoreductasein NLF cells was significantly increased. In nonsmokers, a similar trend for reduction in virus quantity with BSH did not reach statistical significance.In smokers, short term ingestion of broccoli sprout homogenates appears to significantly reduce some virus-induced markers of inflammation, as well as reducing virus quantity. Nutritional antioxidant interventions have promise as a safe, low-cost strategy for reducing influenza risk among smokers and other at risk populations.ClinicalTrials.gov NCT01269723.

  5. HLA-associated alterations in replication capacity of chimeric NL4-3 viruses carrying gag-protease from elite controllers of human immunodeficiency virus type 1.

    Science.gov (United States)

    Miura, Toshiyuki; Brockman, Mark A; Brumme, Zabrina L; Brumme, Chanson J; Pereyra, Florencia; Trocha, Alicja; Block, Brian L; Schneidewind, Arne; Allen, Todd M; Heckerman, David; Walker, Bruce D

    2009-01-01

    Human immunodeficiency virus type 1 (HIV-1)-infected persons who maintain plasma viral loads of viruses (VRC) obtained from EC (n = 54) compared to those from chronic progressors (CP; n = 41) by constructing chimeric viruses using patient-derived gag-protease sequences amplified from plasma HIV RNA and inserted into an NL4-3 backbone. The chimeric viruses generated from EC displayed lower VRC than did viruses from CP (P viruses from B*57(+) EC (n = 18) demonstrated lower VRC than did viruses from B*57(+) CP (n = 8, P = 0.0245). Differences in VRC between EC and CP were also observed for viruses obtained from individuals expressing no described "protective" alleles (P = 0.0065). Intriguingly, two common HLA alleles, A*02 and B*07, were associated with higher VRC (P = 0.0140 and 0.0097, respectively), and there was no difference in VRC between EC and CP sharing these common HLA alleles. These findings indicate that cytotoxic T-lymphocyte (CTL) selection pressure on gag-protease alters VRC, and HIV-specific CTLs inducing escape mutations with fitness costs in this region may be important for strict viremia control in EC of HIV.

  6. A single amino acid at N-terminal region of the 2b protein of cucumber mosaic virus strain m1 has a pivotal role in virus attenuation.

    Science.gov (United States)

    Maneechoat, Phoowanarth; Takeshita, Minoru; Uenoyama, Misa; Nakatsukasa, Maki; Kuroda, Atsuko; Furuya, Naruto; Tsuchiya, Kenichi

    2015-02-02

    Host responses to infection by a mild strain of cucumber mosaic virus, termed CMV-m1, were re-examined in several plant species in comparison with those by a severe strain CMV-Y. Mild systemic symptoms were developed on the six plant species inoculated with CMV-m1. Virus titer in the Nicotiana benthamiana plants infected with CMV-m1 was significantly lower than those infected with CMV-Y, although infection by CMV-m1 interfered with further infection by CMV-Y in the plants. Subsequently, the attenuated virulence of CMV-m1 was analyzed by reassortment and recombination analyses between CMV-m1 and CMV-Y RNAs. The results suggested that the 2b protein of CMV-m1 (m1-2b) is involved in the formation of mild symptoms in N. benthamiana. Furthermore, site-directed mutagenesis demonstrated that Thr18 of m1-2b is responsible for formation of mild symptoms. Local RNA silencing suppressor activity of m1-2b was a little lower than that of severe strain CMV-Y. We discuss the relationship between attenuation of CMV-m1 and the features of m1-2b.

  7. Attenuation of Sindbis virus neurovirulence by using defined mutations in nontranslated regions of the genome RNA

    NARCIS (Netherlands)

    Kuhn, R J; Griffin, D E; Zhang, H; Niesters, Hubert G. M.; Strauss, J H

    1992-01-01

    We examined a panel of Sindbis virus mutants containing defined mutations in the 5' nontranslated region of the genome RNA, in the 3' nontranslated region, or in both for their growth in cultured cells and virulence in newborn mice. In cultured cells, these viruses all had defects in RNA synthesis a

  8. Imaging characteristics, tissue distribution, and spread of a novel oncolytic vaccinia virus carrying the human sodium iodide symporter.

    Directory of Open Access Journals (Sweden)

    Dana Haddad

    Full Text Available INTRODUCTION: Oncolytic viruses show promise for treating cancer. However, to assess therapy and potential toxicity, a noninvasive imaging modality is needed. This study aims to determine the in vivo biodistribution, and imaging and timing characteristics of a vaccinia virus, GLV-1h153, encoding the human sodium iodide symporter (hNIS. METHODS: GLV-1h153 was modified from GLV-1h68 to encode the hNIS gene. Timing of cellular uptake of radioiodide (131I in human pancreatic carcinoma cells PANC-1 was assessed using radiouptake assays. Viral biodistribution was determined in nude mice bearing PANC-1 xenografts, and infection in tumors confirmed histologically and optically via Green Fluorescent Protein (GFP and bioluminescence. Timing characteristics of enhanced radiouptake in xenografts were assessed via (124I-positron emission tomography (PET. Detection of systemic administration of virus was investigated with both (124I-PET and 99m-technecium gamma-scintigraphy. RESULTS: GLV-1h153 successfully facilitated time-dependent intracellular uptake of (131I in PANC-1 cells with a maximum uptake at 24 hours postinfection (P<0.05. In vivo, biodistribution profiles revealed persistence of virus in tumors 5 weeks postinjection at 10(9 plaque-forming unit (PFU/gm tissue, with the virus mainly cleared from all other major organs. Tumor infection by GLV-1h153 was confirmed via optical imaging and histology. GLV-1h153 facilitated imaging virus replication in tumors via PET even at 8 hours post radiotracer injection, with a mean %ID/gm of 3.82 ± 0.46 (P<0.05 2 days after intratumoral administration of virus, confirmed via tissue radiouptake assays. One week post systemic administration, GLV-1h153-infected tumors were detected via (124I-PET and 99m-technecium-scintigraphy. CONCLUSION: GLV-1h153 is a promising oncolytic agent against pancreatic cancer with a promising biosafety profile. GLV-1h153 facilitated time-dependent hNIS-specific radiouptake in pancreatic

  9. Vaccinia virus infection attenuates innate immune responses and antigen presentation by epidermal dendritic cells.

    Science.gov (United States)

    Deng, Liang; Dai, Peihong; Ding, Wanhong; Granstein, Richard D; Shuman, Stewart

    2006-10-01

    Langerhans cells (LCs) are antigen-presenting cells in the skin that play sentinel roles in host immune defense by secreting proinflammatory molecules and activating T cells. Here we studied the interaction of vaccinia virus with XS52 cells, a murine epidermis-derived dendritic cell line that serves as a surrogate model for LCs. We found that vaccinia virus productively infects XS52 cells, yet this infection displays an atypical response to anti-poxvirus agents. Whereas adenosine N1-oxide blocked virus production and viral protein synthesis during a synchronous infection, cytosine arabinoside had no effect at concentrations sufficient to prevent virus replication in BSC40 monkey kidney cells. Vaccinia virus infection of XS52 cells not only failed to elicit the production of various cytokines, including tumor necrosis factor alpha (TNF-alpha), interleukin-1beta (IL-1beta), IL-6, IL-10, IL-12 p40, alpha interferon (IFN-alpha), and IFN-gamma, it actively inhibited the production of proinflammatory cytokines TNF-alpha and IL-6 by XS52 cells in response to exogenous lipopolysaccharide (LPS) or poly(I:C). Infection with a vaccinia virus mutant lacking the E3L gene resulted in TNF-alpha secretion in the absence of applied stimuli. Infection of XS52 cells or BSC40 cells with the DeltaE3L virus, but not wild-type vaccinia virus, triggered proteolytic decay of IkappaBalpha. These results suggest a novel role for the E3L protein as an antagonist of the NF-kappaB signaling pathway. DeltaE3L-infected XS52 cells secreted higher levels of TNF-alpha and IL-6 in response to LPS and poly(I:C) than did cells infected with the wild-type virus. XS52 cells were productively infected by a vaccinia virus mutant lacking the K1L gene. DeltaK1L-infected cells secreted higher levels of TNF-alpha and IL-6 in response to LPS than wild-type virus-infected cells. Vaccinia virus infection of primary LCs harvested from mouse epidermis was nonpermissive, although a viral reporter protein was

  10. Introduction of silent mutations into the NP gene of influenza A viruses as a possible strategy for the creation of a live attenuated vaccine.

    Science.gov (United States)

    Anhlan, Darisuren; Hrincius, Eike-Roman; Scholtissek, Christoph; Ludwig, Stephan

    2012-06-22

    The nucleoprotein (NP) of influenza A virus (IAV) is associated with many different functions including host range restriction. Multiple sequence alignment analyses of 748 NP gene sequences from GenBank revealed a highly conserved region of 60 nucleotides within the ORF at the 3'-ends of the cRNA, in some codons even silent mutations were not found. This suggests that the RNA structure integrity within this region is crucial for IAV replication. To explore the impact of these conserved nucleotides for viral replication we created mutant viruses with one or more silent mutations in the respective region of the NP gene of the IAV strain A/WSN/33 (H1N1) (WSN). Assessment of viral replication of these WSN mutant viruses showed significant growth disadvantages when compared to the corresponding parental strain. On the basis of these findings we tested whether the attenuation of IAV by introduction of silent mutations into the NP gene may serve as a strategy to create a live attenuated vaccine. Mice vaccinated with the attenuated WSN mutant survived a lethal challenge dose of wild type WSN virus or the mouse adapted pandemic H1N1v strain A/Hamburg/4/2009. Thus, introduction of silent mutations in the NP of IAV is a feasible approach for a novel vaccination strategy allowing attenuation of the master strain but leaves the antigenicity of the gene product unaltered. This principle is potentially applicable for all viruses with segmented genomes.

  11. Synthesis of multivalent sialyllactosamine-carrying glyco-nanoparticles with high affinity to the human influenza virus hemagglutinin.

    Science.gov (United States)

    Ogata, Makoto; Umemura, Seiichiro; Sugiyama, Naohiro; Kuwano, Natsuki; Koizumi, Ami; Sawada, Tadakazu; Yanase, Michiyo; Takaha, Takeshi; Kadokawa, Jun-Ichi; Usui, Taichi

    2016-11-20

    A series of multivalent sialoglyco-conjugated nanoparticles were efficiently synthesized by using highly-branched α-glucuronic acid-linked cyclic dextrins (GlcA-HBCD) as a backbone. The sialoglycoside-moieties, with varying degrees of substitution, could be incorporated onto the preformed nanoparticles. These synthesized particles, which are highly soluble in aqueous solution, were shown to have a spherical nanostructure with a diameter of approximately 15nm. The interactions of the sialoglyco-nanoparticles (Neu5Acα2,6LacNAc-GlcA-HBCDs) with human influenza virus strain A/Beijing/262/95 (H1N1) were investigated using a hemagglutination inhibition assay. The sialoglyco-nanoparticle, in which the number of sialic acid substitution is 30, acted as a powerful inhibitor of virus binding activity. We show that both distance and multiplicity of effective ligand-virus formation play important roles in enhancing viral inhibition. Our results indicate that the GlcA-HBCD backbone can be used as a novel spherical nanocluster material for preparing a variety of glyco-nanoparticles to facilitate molecular recognition.

  12. Generation of Live Attenuated Novel Influenza Virus A/California/7/09 (H1N1) Vaccines with High Yield in Embryonated Chicken Eggs ▿

    Science.gov (United States)

    Chen, Zhongying; Wang, Weijia; Zhou, Helen; Suguitan, Amorsolo L.; Shambaugh, Cindy; Kim, Lomi; Zhao, Jackie; Kemble, George; Jin, Hong

    2010-01-01

    Several live attenuated influenza virus A/California/7/09 (H1N1) (CA09) candidate vaccine variants that possess the hemagglutinin (HA) and neuraminidase (NA) gene segments from the CA09 virus and six internal protein gene segments from the cold-adapted influenza virus A/Ann Arbor/6/60 (H2N2) virus were generated by reverse genetics. The reassortant viruses replicated relatively poorly in embryonated chicken eggs. To improve virus growth in eggs, reassortants expressing the HA and NA of CA09 were passaged in MDCK cells and variants exhibiting large-plaque morphology were isolated. These variants replicated at levels approximately 10-fold higher than the rate of replication of the parental strains in embryonated chicken eggs. Sequence analysis indicated that single amino acid changes at positions 119, 153, 154, and 186 were responsible for the improved growth properties in MDCK cells and eggs. In addition, the introduction of a mutation at residue 155 that was previously shown to enhance the replication of a 1976 swine influenza virus also significantly improved the replication of the CA09 virus in eggs. Each variant was further evaluated for receptor binding preference, antigenicity, attenuation phenotype, and immunogenicity. Mutations at residues 153, 154, and 155 drastically reduced viral antigenicity, which made these mutants unsuitable as vaccine candidates. However, changes at residues 119 and 186 did not affect virus antigenicity or immunogenicity, justifying their inclusion in live attenuated vaccine candidates to protect against the currently circulating 2009 swine origin H1N1 viruses. PMID:19864389

  13. Generation of live attenuated novel influenza virus A/California/7/09 (H1N1) vaccines with high yield in embryonated chicken eggs.

    Science.gov (United States)

    Chen, Zhongying; Wang, Weijia; Zhou, Helen; Suguitan, Amorsolo L; Shambaugh, Cindy; Kim, Lomi; Zhao, Jackie; Kemble, George; Jin, Hong

    2010-01-01

    Several live attenuated influenza virus A/California/7/09 (H1N1) (CA09) candidate vaccine variants that possess the hemagglutinin (HA) and neuraminidase (NA) gene segments from the CA09 virus and six internal protein gene segments from the cold-adapted influenza virus A/Ann Arbor/6/60 (H2N2) virus were generated by reverse genetics. The reassortant viruses replicated relatively poorly in embryonated chicken eggs. To improve virus growth in eggs, reassortants expressing the HA and NA of CA09 were passaged in MDCK cells and variants exhibiting large-plaque morphology were isolated. These variants replicated at levels approximately 10-fold higher than the rate of replication of the parental strains in embryonated chicken eggs. Sequence analysis indicated that single amino acid changes at positions 119, 153, 154, and 186 were responsible for the improved growth properties in MDCK cells and eggs. In addition, the introduction of a mutation at residue 155 that was previously shown to enhance the replication of a 1976 swine influenza virus also significantly improved the replication of the CA09 virus in eggs. Each variant was further evaluated for receptor binding preference, antigenicity, attenuation phenotype, and immunogenicity. Mutations at residues 153, 154, and 155 drastically reduced viral antigenicity, which made these mutants unsuitable as vaccine candidates. However, changes at residues 119 and 186 did not affect virus antigenicity or immunogenicity, justifying their inclusion in live attenuated vaccine candidates to protect against the currently circulating 2009 swine origin H1N1 viruses.

  14. Extracts from rabbit skin inflamed by the vaccinia virus attenuate bupivacaine-induced spinal neurotoxicity in pregnant rats

    Institute of Scientific and Technical Information of China (English)

    Rui Cui; Shiyuan Xu; Liang Wang; Hongyi Lei; Qingxiang Cai; Hongfei Zhang; Dongmei Wang

    2013-01-01

    Extracts from rabbit skin inflamed by the vaccinia virus can relieve pain and promote repair of nerve injury. The present study intraperitoneally injected extracts from rabbit skin inflamed by the vaccinia virus for 3 and 4 days prior to and following intrathecal injection of bupivacaine into pregnant rats. The pain threshold test after bupivacaine injection showed that the maximum possible effect of tail-flick latency peaked 1 day after intrathecal injection of bupivacaine in the extract-pretreatment group, and gradually decreased, while the maximum possible effect in the bupivacaine group continued to increase after intrathecal injection of bupivacaine. Histological observation showed that after 4 days of intrathecal injection of bupivacaine, the number of shrunken, vacuolated, apoptotic and caspase-9-positive cells in the dorsal root ganglion in the extract-pretreatment group was significantly reduced compared with the bupivacaine group. These findings indicate that extracts from rabbit skin inflamed by the vaccinia virus can attenuate neurotoxicity induced by intrathecal injection of bupivacaine in pregnant rats, possibly by inhibiting caspase-9 protein expression and suppressing nerve cell apoptosis.

  15. A live attenuated H7N7 candidate vaccine virus induces neutralizing antibody that confers protection from challenge in mice, ferrets and monkeys

    Science.gov (United States)

    A live attenuated H7N7 candidate vaccine virus was generated by reverse genetics using the modified hemagglutinin (HA) and neuraminidase (NA) genes of HP A/Netherlands/219/03 (NL/03) (H7N7) wild-type (wt) virus and the six internal protein genes of the cold-adapted (ca) A/Ann Arbor/6/60 ca (AA ca) (...

  16. Vat, an amazing gene conferring resistance to aphids and viruses they carry: from molecular structure to field effects

    Directory of Open Access Journals (Sweden)

    Nathalie Boissot

    2016-09-01

    Full Text Available We review half a century of research on Cucumis melo resistance to Aphis gossypii from molecular to field levels. The Vat gene is unique in conferring resistance to both A. gossypii and the viruses it transmits. This double phenotype is aphid clone-dependent and has been observed in 25 melon accessions, mostly from Asia. It is controlled by a cluster of genes including CC-NLR, which has been characterized in detail. Copy-number polymorphisms (for the whole gene and for a domain that stands out in the LLR region and single-nucleotide polymorphisms have been identified in the Vat cluster. The role of these polymorphisms in plant aphid/interactions remains unclear. The Vat gene structure suggests a functioning with separate recognition and response phases. During the recognition phase, the VAT protein is thought to interact (likely indirectly with an aphid effector introduced during cell puncture by the aphid. A few hours later, several miRNAs are upregulated in Vat plants. Peroxidase activity increases, and callose and lignin are deposited in the walls of the cells adjacent to the stylet path, disturbing aphid behavior. In aphids feeding on Vat plants, Piwi-interacting RNA-like sequences are abundant and the levels of other miRNAs are modified. At the plant level, resistance to aphids is quantitative (aphids escape the plant and display low rates of reproduction. Resistance to viruses is qualitative and local.Durability of NLR genes is highly variable. A. gossypii clones are adapted to Vat resistance, either by introducing a new effector that interferes with the deployment of plant defenses, or by adapting to the defenses it triggered. Viruses transmitted in a non-persistent manner cannot adapt to Vat resistance. At population level, Vat reduces aphid density and genetic diversity. The durability of Vat resistance to A. gossypii populations depends strongly on the agro-ecosystem, including, in particular, the presence of other cucurbit crops

  17. Enhancement or attenuation of disease by deletion of genes from Citrus tristeza virus.

    Science.gov (United States)

    Tatineni, Satyanarayana; Dawson, William O

    2012-08-01

    Stem pitting is a common virus-induced disease of perennial woody plants induced by a range of different viruses. The phenotype results from sporadic areas of the stem in which normal xylem and phloem development is prevented during growth of stems. These alterations interfere with carbohydrate transport, resulting in reduced plant growth and yield. Citrus tristeza virus (CTV), a phloem-limited closterovirus, induces economically important stem-pitting diseases of citrus. CTV has three nonconserved genes (p33, p18, and p13) that are not related to genes of other viruses and that are not required for systemic infection of some species of citrus, which allowed us to examine the effect of deletions of these genes on symptom phenotypes. In the most susceptible experimental host, Citrus macrophylla, the full-length virus causes only very mild stem-pitting symptoms. Surprisingly, we found that certain deletion combinations (p33 and p18 and/or p13) induced greatly increased stem-pitting symptoms, while other combinations (p13 or p13 plus p18) resulted in reduced stem pitting. These results suggest that the stem-pitting phenotype, which is one of more economically important disease phenotypes, can result not from a specific sequence or protein but from a balance between the expression of different viral genes. Unexpectedly, using green fluorescent protein-tagged full-length virus and deletion mutants (CTV9Δp33 and CTV9Δp33Δp18Δp13), the virus was found at pitted areas in abnormal locations outside the normal ring of phloem. Thus, increased stem pitting was associated not only with a prevention of xylem production but also with a proliferation of cells that supported viral replication, suggesting that at random areas of stems the virus can elicit changes in cellular differentiation and development.

  18. Recombinant hybrid infectious hematopoietic necrosis virus (IHNV) carrying viral haemorrhagic septicaemia virus (VHSV) G or NV genes show different virulence properities

    DEFF Research Database (Denmark)

    Einer-Jensen, Katja; Biacchesi, S.; Stegmann, Anders

    Viral haemorrhagic septicaemia virus (VHSV) is the economically most important viral disease in European rainbow trout farming. The virus was introduced to fresh water farms in the 1950ies from a reservoir of VHSV in the marine environment. Isolates from wild marine fish and fresh water farms....... By a reverse genetics approach using the related novirrhabdovirus infectious hematopoietic necrosis virus (IHNV) as basis, four hybrid IHNV-VHSV variants were generated. These chimeric variants included substitution of the IHNV glyco(G) or nonstrutrual (Nv) protein with the corresponding G or Nv-protein from...... or fresh water VHSV. Recombinant IHNV gained higher virulence following substitution of the homologous G gene with the VHSV G gene, while the opposite was the case following substitution of the Nv gene. These findings suggest that higher virulence of VHSV compared to IHNV might be related to the G protein...

  19. Vat, an Amazing Gene Conferring Resistance to Aphids and Viruses They Carry: From Molecular Structure to Field Effects

    Science.gov (United States)

    Boissot, Nathalie; Schoeny, Alexandra; Vanlerberghe-Masutti, Flavie

    2016-01-01

    We review half a century of research on Cucumis melo resistance to Aphis gossypii from molecular to field levels. The Vat gene is unique in conferring resistance to both A. gossypii and the viruses it transmits. This double phenotype is aphid clone-dependent and has been observed in 25 melon accessions, mostly from Asia. It is controlled by a cluster of genes including CC-NLR, which has been characterized in detail. Copy-number polymorphisms (for the whole gene and for a domain that stands out in the LLR region) and single-nucleotide polymorphisms have been identified in the Vat cluster. The role of these polymorphisms in plant/aphid interactions remains unclear. The Vat gene structure suggests a functioning with separate recognition and response phases. During the recognition phase, the VAT protein is thought to interact (likely indirectly) with an aphid effector introduced during cell puncture by the aphid. A few hours later, several miRNAs are upregulated in Vat plants. Peroxidase activity increases, and callose and lignin are deposited in the walls of the cells adjacent to the stylet path, disturbing aphid behavior. In aphids feeding on Vat plants, Piwi-interacting RNA-like sequences are abundant and the levels of other miRNAs are modified. At the plant level, resistance to aphids is quantitative (aphids escape the plant and display low rates of reproduction). Resistance to viruses is qualitative and local. Durability of NLR genes is highly variable. A. gossypii clones are adapted to Vat resistance, either by introducing a new effector that interferes with the deployment of plant defenses, or by adapting to the defenses it triggered. Viruses transmitted in a non-persistent manner cannot adapt to Vat resistance. At population level, Vat reduces aphid density and genetic diversity. The durability of Vat resistance to A. gossypii populations depends strongly on the agro-ecosystem, including, in particular, the presence of other cucurbit crops serving as

  20. Virus-Like Particles of Chimeric Recombinant Porcine Circovirus Type 2 as Antigen Vehicle Carrying Foreign Epitopes

    Directory of Open Access Journals (Sweden)

    Huawei Zhang

    2014-12-01

    Full Text Available Virus-like particles (VLPs of chimeric porcine circovirus type 2 (PCV2 were generated by replacing the nuclear localization signal (NLS; at 1–39 aa of PCV2 capsid protein (Cap with classical swine fever virus (CSFV T-cell epitope (1446–1460 aa, CSFV B-cell epitope (693–716 aa and CSFV T-cell epitope conjugated with B-cell epitope. The recombinant proteins were expressed using the baculovirus expression system and detected by immunoblotting and indirect immunofluorescence assay. The abilities to form PCV2 VLPs were confirmed by transmission electron microscopy. Immunogenicities of the three recombinant proteins were evaluated in mice. Our Results indicated that Cap protein NLS deletion or substitution with CSFV epitopes did not affect the VLPs assembly. Three chimeric Cap proteins could form VLPs and induce efficient humoral and cellular immunity against PCV2 and CSFV in mice. Results show that PCV2 VLPs can be used as an efficient antigen carrier for delivery of foreign epitopes, and a potential novel vaccine.

  1. Synonymous deoptimization of the foot-and-mouth disease virus P1 coding region causes attenuation in vivo while inducing a strong neutralizing antibody response

    Science.gov (United States)

    Codon bias deoptimization has been previously used to successfully attenuate human pathogens including polio, respiratory syncytial and influenza viruses. We have applied a similar technology to deoptimize the capsid coding region (P1 region) of the cDNA infectious clone of foot-and-mouth disease vi...

  2. Development of a dual-protective live attenuated vaccine against H5N1 and H9N2 avian influenza viruses by modifying the NS1 gene.

    Science.gov (United States)

    Choi, Eun-hye; Song, Min-Suk; Park, Su-Jin; Pascua, Philippe Noriel Q; Baek, Yun Hee; Kwon, Hyeok-il; Kim, Eun-Ha; Kim, Semi; Jang, Hyung-Kwan; Poo, Haryoung; Kim, Chul-Joong; Choi, Young Ki

    2015-07-01

    An increasing number of outbreaks of avian influenza H5N1 and H9N2 viruses in poultry have caused serious economic losses and raised concerns for human health due to the risk of zoonotic transmission. However, licensed H5N1 and H9N2 vaccines for animals and humans have not been developed. Thus, to develop a dual H5N1 and H9N2 live-attenuated influenza vaccine (LAIV), the HA and NA genes from a virulent mouse-adapted avian H5N2 (A/WB/Korea/ma81/06) virus and a recently isolated chicken H9N2 (A/CK/Korea/116/06) virus, respectively, were introduced into the A/Puerto Rico/8/34 backbone expressing truncated NS1 proteins (NS1-73, NS1-86, NS1-101, NS1-122) but still possessing a full-length NS gene. Two H5N2/NS1-LAIV viruses (H5N2/NS1-86 and H5N2/NS1-101) were highly attenuated compared with the full-length and remaining H5N2/NS-LAIV viruses in a mouse model. Furthermore, viruses containing NS1 modifications were found to induce more IFN-β activation than viruses with full-length NS1 proteins and were correspondingly attenuated in mice. Intranasal vaccination with a single dose (10(4.0) PFU/ml) of these viruses completely protected mice from a lethal challenge with the homologous A/WB/Korea/ma81/06 (H5N2), heterologous highly pathogenic A/EM/Korea/W149/06 (H5N1), and heterosubtypic highly virulent mouse-adapted H9N2 viruses. This study clearly demonstrates that the modified H5N2/NS1-LAIV viruses attenuated through the introduction of mutations in the NS1 coding region display characteristics that are desirable for live attenuated vaccines and hold potential as vaccine candidates for mammalian hosts.

  3. Vaccine efficacy of live-attenuated virus, whole inactivated virus and alphavirus vectored subunit vaccines against antigenically distinct H3N2 swine influenza A viruses

    Science.gov (United States)

    Introduction Influenza A virus (IAV) is an important pathogen in swine, and the main intervention strategy is vaccination to induce neutralizing antibodies against the hemagglutinin (HA). Three major antigenic clusters, cyan, red, and green, were identified among H3N2 viruses circulating in pigs in ...

  4. Interferon γ expressed by a recombinant respiratory syncytial virus attenuates virus replication in mice without compromising immunogenicity

    OpenAIRE

    1999-01-01

    Interferon γ (IFN-γ) has pleiotropic biological effects, including intrinsic antiviral activity as well as stimulation and regulation of immune responses. An infectious recombinant human respiratory syncytial virus (rRSV/mIFN-γ) was constructed that encodes murine (m) IFN-γ as a separate gene inserted into the G-F intergenic region. Cultured cells infected with rRSV/mIFN-γ secreted 22 μg mIFN-γ per 106 cells. The replication of rRSV/mIFN-γ, but not that of a control chimeric rRSV containing t...

  5. Nasal lavage natural killer cell function is suppressed in smokers after live attenuated influenza virus

    Science.gov (United States)

    Background Modified function of immune cells in nasal secretions may playa role in the enhanced susceptibility to resp iratory viruses that is seen in smokers. Innate immune cells in nasal secretions have largely been characterized by cellular differentials using morphologic c...

  6. Live Attenuated Vaccine Based on Duck Enteritis Virus against Duck Hepatitis A Virus Types 1 and 3

    Science.gov (United States)

    Zou, Zhong; Ma, Ji; Huang, Kun; Chen, Huanchun; Liu, Ziduo; Jin, Meilin

    2016-01-01

    As causative agents of duck viral hepatitis, duck hepatitis A virus type 1 (DHAV-1) and type 3 (DHAV-3) causes significant economic losses in the duck industry. However, a licensed commercial vaccine that simultaneously controls both pathogens is currently unavailable. Here, we generated duck enteritis virus recombinants (rC-KCE-2VP1) containing both VP1 from DHAV-1 (VP1/DHAV-1) and VP1 from DHAV-3 (VP1/DHAV-3) between UL27 and UL26. A self-cleaving 2A-element of FMDV was inserted between the two different types of VP1, allowing production of both proteins from a single open reading frame. Immunofluorescence and Western blot analysis results demonstrated that both VP1 proteins were robustly expressed in rC-KCE-2VP1-infected chicken embryo fibroblasts. Ducks that received a single dose of rC-KCE-2VP1 showed potent humoral and cellular immune responses and were completely protected against challenges of both pathogenic DHAV-1 and DHAV-3 strains. The protection was rapid, achieved as early as 3 days after vaccination. Moreover, viral replication was fully blocked in vaccinated ducks as early as 1 week post-vaccination. These results demonstrated, for the first time, that recombinant rC-KCE-2VP1 is potential fast-acting vaccine against DHAV-1 and DHAV-3. PMID:27777571

  7. Effect of Broccoli Sprouts and Live Attenuated Influenza Virus on Peripheral Blood Natural Killer Cells: A Randomized, Double-Blind Study.

    Directory of Open Access Journals (Sweden)

    Loretta Müller

    Full Text Available Enhancing antiviral host defense responses through nutritional supplementation would be an attractive strategy in the fight against influenza. Using inoculation with live attenuated influenza virus (LAIV as an infection model, we have recently shown that ingestion of sulforaphane-containing broccoli sprout homogenates (BSH reduces markers of viral load in the nose. To investigate the systemic effects of short-term BSH supplementation in the context of LAIV-inoculation, we examined peripheral blood immune cell populations in non-smoking subjects from this study, with a particular focus on NK cells. We carried out a randomized, double-blinded, placebo-controlled study measuring the effects of BSH (N = 13 or placebo (alfalfa sprout homogenate, ASH; N = 16 on peripheral blood mononuclear cell responses to a standard nasal vaccine dose of LAIV in healthy volunteers. Blood was drawn prior to (day-1 and post (day2, day21 LAIV inoculation and analyzed for neutrophils, monocytes, macrophages, T cells, NKT cells, and NK cells. In addition, NK cells were enriched, stimulated, and assessed for surface markers, intracellular markers, and cytotoxic potential by flow cytometry. Overall, LAIV significantly reduced NKT (day2 and day21 and T cell (day2 populations. LAIV decreased NK cell CD56 and CD158b expression, while significantly increasing CD16 expression and cytotoxic potential (on day2. BSH supplementation further increased LAIV-induced granzyme B production (day2 in NK cells compared to ASH and in the BSH group granzyme B levels appeared to be negatively associated with influenza RNA levels in nasal lavage fluid cells. We conclude that nasal influenza infection may induce complex changes in peripheral blood NK cell activation, and that BSH increases virus-induced peripheral blood NK cell granzyme B production, an effect that may be important for enhanced antiviral defense responses.ClinicalTrials.gov NCT01269723.

  8. Dobrava virus carried by the yellow-necked field mouse Apodemus flavicollis, causing hemorrhagic fever with renal syndrome in Romania.

    Science.gov (United States)

    Panculescu-Gatej, Raluca Ioana; Sirbu, Anca; Dinu, Sorin; Waldstrom, Maria; Heyman, Paul; Murariu, Dimitru; Petrescu, Angela; Szmal, Camelia; Oprisan, Gabriela; Lundkvist, Ake; Ceianu, Cornelia S

    2014-05-01

    Hemorrhagic fever with renal syndrome (HFRS) has been confirmed by serological methods during recent years in Romania. In the present study, focus-reduction neutralization tests (FRNT) confirmed Dobrava hantavirus (DOBV) as the causative agent in some HFRS cases, but could not distinguish between DOBV and Saaremaa virus (SAAV) infections in other cases. DOBV was detected by a DOBV-specific TaqMan assay in sera of nine patients out of 22 tested. Partial sequences of the M genomic segment of DOBV were obtained from sera of three patients and revealed the circulation of two DOBV lineages in Romania. Investigation of rodents trapped in Romania found three DOBV-positive Apodemus flavicollis out of 83 rodents tested. Two different DOBV lineages were also detected in A. flavicollis as determined from partial sequences of the M and S genomic segments. Sequences of DOBV in A. flavicollis were either identical or closely related to the sequences obtained from the HFRS patients. The DOBV strains circulating in Romania clustered in two monophyletic groups, together with strains from Slovenia and the north of Greece. This is the first evidence for the circulation of DOBV in wild rodents and for a DOBV etiology of HFRS in Romania.

  9. Cross-Protection against Marburg Virus Strains by Using a Live, Attenuated Recombinant Vaccine

    Science.gov (United States)

    2006-10-01

    Guttieri, B. R. Mothe, T. Larsen, L. E. Hensley, P. B. Jahrling, and H. Feldmann. 2005. Development of a new vaccine for the prevention of Lassa fever ...Manitoba, Canada Received 10 May 2006/Accepted 12 July 2006 Marburg virus (MARV) has been associated with sporadic episodes of hemorrhagic fever ...lineages within the Lake Victoria marburgvirus species of MARV. The original MARV isolates from the 1967 episodes in Marburg, Germany (Popp and Ratayczak

  10. 金丝雀痘诊断与痘病毒致弱试验%Diagnosis of Canary Pox and Study on Attenuation of the Pox Virus

    Institute of Scientific and Technical Information of China (English)

    刘永德; 陶军; 汪毅; 叶陈梁

    2001-01-01

    The canary which had some clinical symptoms was diagnosed as canary pox and the pox virus was isolated.The virus was analyzed by the animal pathogenicity test,virus attenuation,protection of the attenuated virus and virulence return experiment.The results showed that the canary pox virus could adapt to chicken embryo and cause canary death after passage 3 generations.The pox virus had no virulence for canary after passage 8 generations.The virus of 13th generation had no virulence reversion through inoculating canary three times.The canary immunized the 13th generation virus could resist the virulent pox virus challenge.%本试验对送检的金丝雀经实验室诊断,确诊为金丝雀痘。对分离的痘病毒进行动物致病性试验、病毒分离传代和致弱试验、致弱毒保护力试验和返强试验。结果表明:金丝雀痘病毒经鸡胚盲传3代后能适应鸡胚并致死金丝雀,8代后无致病性,13代毒快速通过本动物3次无返强现象。金丝雀用第13代毒刺种后30天能抵抗强毒攻击。

  11. Construction of the recombinant vector carrying herpes simplex virus thymidine kinase and cytokine genes expressed in cell line Tca8113

    Institute of Scientific and Technical Information of China (English)

    JI Guang-hui; ZOU Jing-zhi; QU Le; YUE Ying; KUAI Jian-ke

    2004-01-01

    Objective: To construct expression vector containing fusion genes of herpes simplex virus thymidine kinase(Hsv-tk), Interleukin-2(IL-2) with internal ribosome entry sites(IRES), and to assess their expression in cell lineTca8113. Methods: IL-2 cDNA was obtained by reverse transcription. Hsv-tk, IL-2 and IRES genes were amplified by PCR. The purified amplification products were inserted into pGEM-T-Easy, and transformed into E. coli JM109. The purified recombinant plasmids were identified by restriction endonucleases. The recombinant plasmids were digested and pEGFPN3 were linearized, DNA fragments of Hsv-tk, IRES and IL-2 were ligated into linearized pEGFP-N3, and then transferred into E. coli JM109. The recombinant tk-IL-2 genes were cloned separately and introduced into the expression vector pEGFPN3 containing GFP. The recombinant vectors were identified by their restriction sites through PCR. The plasmids pEGFP-TI was also transfected into Tca8113 cells by calcium phosphate method for the expression of fusion proteins. Fusion genes expressing vector PL(TI)SN was generated by the fusion of HSV-tk, IRES and IL-2 with the use of DNA recombination technology. The recombinant retroviruses were transferred into Tca8113 cells by lipofectamine. The positive clones were obtained after G418 selection and named Tca/TI respectively. Results: The pEGFP-TI pasmid was identified respectively by restriction endonucleases, and their fragment sizes were 1 120 bp and 450 bp. The pEGFP-TI pasmid as templates were amplified respectively by PCR, and their PCR products were 1 120 bp and 450 bp. The pEGFP-TI vectors were used to transfect Tca8113 cell, and the cells with fluorescence accounted for 60 % of the total amount. Conclusion: pFGFP- tk- IRES- IL-2 expressing vector is easy to assess the expression of tk-IRES-IL-2-GFP fusion protein localization in transfected cells. The successful construction of expressing vector containing fusion genes of Hsv-tk, IRES and IL-2 may be

  12. Successful cross-protective efficacy induced by heat-adapted live attenuated nephropathogenic infectious bronchitis virus derived from a natural recombinant strain.

    Science.gov (United States)

    Lim, Tae-Hyun; Youn, Ha-Na; Yuk, Seong-Su; Kwon, Jung-Hoon; Hong, Woo-Tack; Gwon, Gyeong-Bin; Lee, Jung-Ah; Lee, Joong-Bok; Lee, Sang-Won; Song, Chang-Seon

    2015-12-16

    A natural recombinant nephropathogenic K40/09 strain of infectious bronchitis virus (IBV) was heat-adapted for possible future use as live attenuated vaccine. The K40/09 strain was selected during successive serial passages in specific-pathogen free (SPF) embryonated eggs at sub-optimal higher temperature (56°C). Unlike the parental strain, the attenuated strain, designated K40/09 HP50, was found to be safe in 1-day-old SPF chicks, which showed neither mortality nor signs of morbidity, and rarely induced ciliostasis or histological changes in the trachea and kidney after intraocular and fine-spray administration. K40/09 HP50 provided almost complete protection against two distinct subgroups of a nephropathogenic strain (KM91-like and QX-like subgroup) and elicited the production of high titers of neutralizing antibody (neutralization index of 3.6). We conclude that the K40/09 HP50 vaccine virus is rapidly attenuated by heat adaptation and exhibits the desired level of attenuation, immunogenicity, and protective efficacy required for a live attenuated vaccine. These results indicate that the K40/09 vaccine could be helpful for the reduction of economic losses caused by recently emergent nephropathogenic IBV infection in many countries.

  13. Transcriptome Analysis of Human Peripheral Blood Mononuclear Cells Exposed to Lassa Virus and to the Attenuated Mopeia/Lassa Reassortant 29 (ML29), a Vaccine Candidate

    Science.gov (United States)

    Zapata, Juan Carlos; Carrion, Ricardo; Patterson, Jean L.; Crasta, Oswald; Zhang, Yan; Mani, Sachin; Jett, Marti; Poonia, Bhawna; Djavani, Mahmoud; White, David M.; Lukashevich, Igor S.; Salvato, Maria S.

    2013-01-01

    Lassa virus (LASV) is the causative agent of Lassa Fever and is responsible for several hundred thousand infections and thousands of deaths annually in West Africa. LASV and the non-pathogenic Mopeia virus (MOPV) are both rodent-borne African arenaviruses. A live attenuated reassortant of MOPV and LASV, designated ML29, protects rodents and primates from LASV challenge and appears to be more attenuated than MOPV. To gain better insight into LASV-induced pathology and mechanism of attenuation we performed gene expression profiling in human peripheral blood mononuclear cells (PBMC) exposed to LASV and the vaccine candidate ML29. PBMC from healthy human subjects were exposed to either LASV or ML29. Although most PBMC are non-permissive for virus replication, they remain susceptible to signal transduction by virus particles. Total RNA was extracted and global gene expression was evaluated during the first 24 hours using high-density microarrays. Results were validated using RT-PCR, flow cytometry and ELISA. LASV and ML29 elicited differential expression of interferon-stimulated genes (ISG), as well as genes involved in apoptosis, NF-kB signaling and the coagulation pathways. These genes could eventually serve as biomarkers to predict disease outcomes. The remarkable differential expression of thrombomodulin, a key regulator of inflammation and coagulation, suggests its involvement with vascular abnormalities and mortality in Lassa fever disease. PMID:24069471

  14. Transcriptome analysis of human peripheral blood mononuclear cells exposed to Lassa virus and to the attenuated Mopeia/Lassa reassortant 29 (ML29, a vaccine candidate.

    Directory of Open Access Journals (Sweden)

    Juan Carlos Zapata

    Full Text Available Lassa virus (LASV is the causative agent of Lassa Fever and is responsible for several hundred thousand infections and thousands of deaths annually in West Africa. LASV and the non-pathogenic Mopeia virus (MOPV are both rodent-borne African arenaviruses. A live attenuated reassortant of MOPV and LASV, designated ML29, protects rodents and primates from LASV challenge and appears to be more attenuated than MOPV. To gain better insight into LASV-induced pathology and mechanism of attenuation we performed gene expression profiling in human peripheral blood mononuclear cells (PBMC exposed to LASV and the vaccine candidate ML29. PBMC from healthy human subjects were exposed to either LASV or ML29. Although most PBMC are non-permissive for virus replication, they remain susceptible to signal transduction by virus particles. Total RNA was extracted and global gene expression was evaluated during the first 24 hours using high-density microarrays. Results were validated using RT-PCR, flow cytometry and ELISA. LASV and ML29 elicited differential expression of interferon-stimulated genes (ISG, as well as genes involved in apoptosis, NF-kB signaling and the coagulation pathways. These genes could eventually serve as biomarkers to predict disease outcomes. The remarkable differential expression of thrombomodulin, a key regulator of inflammation and coagulation, suggests its involvement with vascular abnormalities and mortality in Lassa fever disease.

  15. Transcriptome analysis of human peripheral blood mononuclear cells exposed to Lassa virus and to the attenuated Mopeia/Lassa reassortant 29 (ML29), a vaccine candidate.

    Science.gov (United States)

    Zapata, Juan Carlos; Carrion, Ricardo; Patterson, Jean L; Crasta, Oswald; Zhang, Yan; Mani, Sachin; Jett, Marti; Poonia, Bhawna; Djavani, Mahmoud; White, David M; Lukashevich, Igor S; Salvato, Maria S

    2013-01-01

    Lassa virus (LASV) is the causative agent of Lassa Fever and is responsible for several hundred thousand infections and thousands of deaths annually in West Africa. LASV and the non-pathogenic Mopeia virus (MOPV) are both rodent-borne African arenaviruses. A live attenuated reassortant of MOPV and LASV, designated ML29, protects rodents and primates from LASV challenge and appears to be more attenuated than MOPV. To gain better insight into LASV-induced pathology and mechanism of attenuation we performed gene expression profiling in human peripheral blood mononuclear cells (PBMC) exposed to LASV and the vaccine candidate ML29. PBMC from healthy human subjects were exposed to either LASV or ML29. Although most PBMC are non-permissive for virus replication, they remain susceptible to signal transduction by virus particles. Total RNA was extracted and global gene expression was evaluated during the first 24 hours using high-density microarrays. Results were validated using RT-PCR, flow cytometry and ELISA. LASV and ML29 elicited differential expression of interferon-stimulated genes (ISG), as well as genes involved in apoptosis, NF-kB signaling and the coagulation pathways. These genes could eventually serve as biomarkers to predict disease outcomes. The remarkable differential expression of thrombomodulin, a key regulator of inflammation and coagulation, suggests its involvement with vascular abnormalities and mortality in Lassa fever disease.

  16. Immunogenic comparison of chimeric adenovirus 5/35 vector carrying optimized human immunodeficiency virus clade C genes and various promoters.

    Science.gov (United States)

    Shoji, Masaki; Yoshizaki, Shinji; Mizuguchi, Hiroyuki; Okuda, Kenji; Shimada, Masaru

    2012-01-01

    Adenovirus vector-based vaccine is a promising approach to protect HIV infection. However, a recent phase IIb clinical trial using the vector did not show its protective efficacy against HIV infection. To improve the vaccine, we explored the transgene protein expression and its immunogenicity using optimized codon usage, promoters and adaptors. We compared protein expression and immunogenicity of adenovirus vector vaccines carrying native or codon usage-optimized HIV-1 clade C gag and env genes expression cassettes driven by different promoters (CMV, CMVi, and CA promoters) and adapters (IRES and F2A). The adenovirus vector vaccine containing optimized gag gene produced higher Gag protein expression and induced higher immune responses than the vector containing native gag gene in mice. Furthermore, CA promoter generated higher transgene expression and elicited higher immune responses than other two popularly used promoters (CMV and CMVi). The second gene expression using F2A adaptor resulted in higher protein expression and immunity than that of using IRES and direct fusion protein. Taken together, the adenovirus vector containing the expression cassette with CA promoter, optimized HIV-1 clade C gene and an F2A adaptor produced the best protein expression and elicited the highest transgene-specific immune responses. This finding would be promising for vaccine design and gene therapy.

  17. Attenuated Salmonella choleraesuis-mediated RNAi targeted to conserved regions against foot-and-mouth disease virus in guinea pigs and swine.

    Science.gov (United States)

    Cong, Wei; Jin, Hong; Jiang, Chengda; Yan, Weiyao; Liu, Mingqiu; Chen, Jiulian; Zuo, Xiaoping; Zheng, Zhaoxin

    2010-01-01

    In this study, specific sequences within three genes (3D, VP4 and 2B) of the foot-and-mouth disease virus (FMDV) genome were determined to be effective RNAi targets. These sequences are highly conserved among different serotype viruses based on sequence analysis. Small interfering RNA (siRNA)-expressing plasmids (p3D-NT19, p3D-NT56, pVP4-NT19, pVP4-NT65 and p2B-NT25) were constructed to express siRNA targeting 3D, VP4 and 2B, respectively. The antiviral potential of these siRNA for various FMDV isolates was investigated in baby hamster kidney (BHK-21) cells and suckling mice. The results show that these siRNA inhibited virus yield 10- to 300-fold for different FMDV isolates of serotype O and serotype Asia I at 48 h post infection in BHK-21 cells compared to control cells. In suckling mice, p3D-NT56 and p2B-NT25 delayed the death of mice. Twenty percent to 40% of the animals that received a single siRNA dose survived 5 days post infection with serotype O or serotype Asia I. We used an attenuated Salmonella choleraesuis (C500) vaccine strain, to carry the plasmid that expresses siRNA directed against the polymerase gene 3D (p3D-NT56) of FMDV. We used guinea pigs to evaluate the inhibitory effects of recombinant S. cho (p3D-NT56/S. cho) on FMDV infection. The results show that 80% of guinea pigs inoculated with 10(9) CFU of p3D-NT56/S. cho and challenged 36 h later with 50 ID(50) of homologous FMDV were protected. We also measured the antiviral activity of p3D-NT56/S. cho in swine. The results indicate that 100% of the animals treated with 5 x 10(9) CFU of p3D-NT56/S. cho were protected in 9 days.

  18. Recombinant adeno-associated virus-mediated delivery of antisense angiotensin Ⅱ receptor 1 gene attenuates hypertension development

    Institute of Scientific and Technical Information of China (English)

    Xu-guang LI; Jiang-tao YAN; Xi-zheng XU; Jia-ning WANG; Li-ming CHENG; Tao WANG; Ping ZUO; Dao-wen WANG

    2007-01-01

    Aim:The renin-angiotensin system plays a crucial role in the development and establishment of hypertension,and the pharmacological blockade of the system results in a reduction in blood pressure. In the present study,we investigated whether the effects of a novel,double-stranded,recombinant adeno-associated virus vector (rAAV)-mediated antisense angiotensin Ⅱ receptor l (AT1R) gene efficiently prevents the development of hypertension induced by a high-salt diet in adult,male Sprague-Dawley (SD) rats. Methods:A rAAV was prepared with a cassette containing a cytomegalovirus promoter and partial cDNA (660 base pairs) for the AT1R inserted in the antisense direction (rAAV-AT1AS). A single tail vein injection of the rAAV-AT1-AS or rAAV-GFP (green fluorescent protein,a reporter gene) was performed in adult,male SD rats. Two weeks after injection,the animals were fed a diet containing 8% NaCI,and the systolic blood pressure was measured weekly using the tail-cuff method for 12 weeks. Results:The high-salt diet induced a significant rise in systolic blood pressure in the rAAV-GFP-treated animals;however,the rAAV-AT:AS treatment attenuated the rise in blood pressure (142.7±4.5 mmHg vs 117±3.8 mmHg,P<0.01),and the hypotensive effect was maintained until the experiments ended at 12 weeks. In the rAAV-GFP-treated animals AT1 was overexpressed in various tissues,especially in the aorta and kidney at mRNA levels;in contrast,rAAV-AT:AS treatment markedly attenuated AT1 expression. Furthermore,rAAV-AT:AS treatment prevented target organ damages from hypertension,including cardiac dysfunction and renal injury compared to the rAAV-GFP group. Conclusion:These results suggest that rAAVmediated anti-AT1 delivery attenuates the development of hypertension and protects against renal injury and cardiac remodeling.

  19. Characterization of a novel mutation in NS1 protein of influenza A virus induced by a chemical substance for the attenuation of pathogenicity.

    Directory of Open Access Journals (Sweden)

    Kohei Sasaki

    Full Text Available It is generally accepted that live attenuated influenza vaccine (LAIV has the potential for use as a vaccination against flu. In this study, we demonstrated the nature of an influenza A virus (IAV mutant induced by treating the IAV with a stable furan derivative, (1R,2R-1-(5'-methylfur-3'-ylpropane-1,2,3-triol (MFPT, which had been isolated from Streptomyces sp. strain FV60 with the objective of it being an LAIV candidate. The resulting MFPT-resistant (MFPTr IAVs possessed attenuated pathogenicity in vitro and in vivo when compared with that of the parent virus (H1N1 subtype, NWS strain. Sequencing analysis revealed that a novel mutation, C490U in ns gene (P164S in NS1, was detected in all MFPTr virus clones tested. Therefore, NS1 might be a main target of MFPT, and it was suggested that the P164S mutation contributed to the attenuated pathogenicity of the mutants. Although the phosphatidylinositol 3-kinase (PI3K/Akt signaling pathway is one of the targets of NS1, the MFPTr virus suppressed the phosphorylation of Akt when compared with the wild-type (WT virus. It was suggested that this might lead to the subsequent inhibition of the cleavage of PARP-1 and caspase-3, which is important for the progression of apoptosis. At the same time, nucleoprotein (NP was found to be retained in the nuclei in MFPTr virus-infected cells while nuclear export of NP was detected in WT virus-infected cells. In addition, the expression levels of interferon-β transcripts were significantly decreased in MFPTr virus-infected cells. From these results it can be shown that the mutation, NS1P164S, might be one of the key residues to control NS1 function concerning the induction of apoptosis. In conclusion, MFPT induced favorable mutation in the ns gene for the attenuation of IAV, and therefore might provide the novel methodology for preparing LAIVs.

  20. Listeria monocytogenes Mutants Carrying Newcastle Disease Virus F Gene Fused to its actA and plcB: In vitro Expression and Immunogenicity in Chickens

    Institute of Scientific and Technical Information of China (English)

    Lingli JIANG; Chunlin KE; Jingjing XU; Jianshun CHEN; Xueyan CHEN; Ning CHEN; Jiangbing SHUAI; Weihuan FANG

    2007-01-01

    Recombinant Listeria monocytogenes mutants carrying Newcastle disease virus (NDV) fusion protein gene F were constructed by homologous recombination. NDV F or its truncated fragment Fa was used as the model heterologous gene to be integrated into actA or plcB downstream of their signal sequences.Correct orientation of the inserted genes was verified by polymerase chain reaction amplification of F or Fa.The inserted F and Fa were expressed in the two recombinants Lm-ΔactA-F and Lm-ΔplcB-Fa as shown by sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blot. Both recombinants exhibited reduced virulence to embryonated eggs and mice by about 1.5-2.5 logs as compared with the parent wild strain 10403S. They were also less invasive than strain 10403S (P<0.05). Chickens receiving the recombinant strains orally or intraperitoneally were partially protected from virulent NDV challenge possibly due to enhancement of non-specific immunity because the antibody titers against the homologous virus strain or the recombinant truncated fusion protein were marginal. Further research is needed in other animal models to see if the low antibody response results from insufficient expression of the heterologous genes as a result of failure of L. monocytogenes or its recombinants to persist or replicate in chickens.

  1. Murine polyomavirus virus-like particles carrying full-length human PSA protect BALB/c mice from outgrowth of a PSA expressing tumor.

    Directory of Open Access Journals (Sweden)

    Mathilda Eriksson

    Full Text Available Virus-like particles (VLPs consist of capsid proteins from viruses and have been shown to be usable as carriers of protein and peptide antigens for immune therapy. In this study, we have produced and assayed murine polyomavirus (MPyV VLPs carrying the entire human Prostate Specific Antigen (PSA (PSA-MPyVLPs for their potential use for immune therapy in a mouse model system. BALB/c mice immunized with PSA-MPyVLPs were only marginally protected against outgrowth of a PSA-expressing tumor. To improve protection, PSA-MPyVLPs were co-injected with adjuvant CpG, either alone or loaded onto murine dendritic cells (DCs. Immunization with PSA-MPyVLPs loaded onto DCs in the presence of CpG was shown to efficiently protect mice from tumor outgrowth. In addition, cellular and humoral immune responses after immunization were examined. PSA-specific CD4(+ and CD8(+ cells were demonstrated, but no PSA-specific IgG antibodies. Vaccination with DCs loaded with PSA-MPyVLPs induced an eight-fold lower titre of anti-VLP antibodies than vaccination with PSA-MPyVLPs alone. In conclusion, immunization of BALB/c mice with PSA-MPyVLPs, loaded onto DCs and co-injected with CpG, induces an efficient PSA-specific tumor protective immune response, including both CD4(+ and CD8(+ cells with a low induction of anti-VLP antibodies.

  2. Carrying Capacity

    DEFF Research Database (Denmark)

    Schroll, Henning; Andersen, Jan; Kjærgård, Bente

    2012-01-01

    A spatial planning act was introduced inIndonesia 1992 and renewed in 2008. It emphasised the planning role of decentralised authorities. The spatial planning act covers both spatial and environmental issues. It defines the concept of carrying capacity and includes definitions of supportive...... carrying capacity (SCC) and assimilative carrying capacity (ACC). The act mandates that the latter two aspects must be taken into consideration in the local spatial plans. The present study aimed at developing a background for a national guideline for carrying capacity in Indonesian provinces and districts...... standard or governmental political objective exists. In most cases it was possible to select a set of indicators, including thresholds that are workable in a carrying capacity planning at the local administrative levels. Not all relevant sectors at the decentralized level were included. Indicators of SCC...

  3. An attenuated virus vaccine appears safe to the central nervous system of rainbow trout (Oncorhynchus mykiss) after intranasal delivery.

    Science.gov (United States)

    Larragoite, Erin T; Tacchi, Luca; LaPatra, Scott E; Salinas, Irene

    2016-02-01

    Nasal vaccines are very effective but the olfactory organ provides direct access of antigens to the brain. Infectious hematopoietic necrosis virus (IHNV) is known to cause high mortalities in salmonids. The purpose of this study is to evaluate the safety of a live attenuated IHNV nasal (I.N) vaccine in rainbow trout (Oncorhynchus mykiss). In the olfactory organ, the vaccine was detected 1 and 4 days after primary I.N vaccination but not in the intramuscular (i.m) or control groups. In the brain, IHNV was detected by RT-qPCR 4 and 21 days after i.m primary vaccination. One i.m and one I.N vaccinated trout were positive at days 4 and 28 days post-boost, respectively. Presence of IHNV in the brain of i.m vaccinated fish correlated with moderate increases in IL-1β and TNF-α expression in this tissue. These results demonstrate that IHNV vaccine lasts for 4 days in the local nasal environment and that nasal vaccination appears to be safe to the CNS of rainbow trout.

  4. Comparative sequence analysis of the P-, M- and L-coding region of the measles virus CAM-70 live attenuated vaccine strain

    Directory of Open Access Journals (Sweden)

    P.R. Santos

    2003-11-01

    Full Text Available Measles virus is a highly contagious agent which causes a major health problem in developing countries. The viral genomic RNA is single-stranded, nonsegmented and of negative polarity. Many live attenuated vaccines for measles virus have been developed using either the prototype Edmonston strain or other locally isolated measles strains. Despite the diverse geographic origins of the vaccine viruses and the different attenuation methods used, there was remarkable sequence similarity of H, F and N genes among all vaccine strains. CAM-70 is a Japanese measles attenuated vaccine strain widely used in Brazilian children and produced by Bio-Manguinhos since 1982. Previous studies have characterized this vaccine biologically and genomically. Nevertheless, only the F, H and N genes have been sequenced. In the present study we have sequenced the remaining P, M and L genes (approximately 1.6, 1.4 and 6.5 kb, respectively to complete the genomic characterization of CAM-70 and to assess the extent of genetic relationship between CAM-70 and other current vaccines. These genes were amplified using long-range or standard RT-PCR techniques, and the cDNA was cloned and automatically sequenced using the dideoxy chain-termination method. The sequence analysis comparing previously sequenced genotype A strains with the CAM-70 Bio-Manguinhos strain showed a low divergence among them. However, the CAM-70 strains (CAM-70 Bio-Manguinhos and a recently sequenced CAM-70 submaster seed strain were assigned to a specific group by phylogenetic analysis using the neighbor-joining method. Information about our product at the genomic level is important for monitoring vaccination campaigns and for future studies of measles virus attenuation.

  5. Dengue type 4 live-attenuated vaccine viruses passaged in vero cells affect genetic stability and dengue-induced hemorrhaging in mice.

    Directory of Open Access Journals (Sweden)

    Hsiang-Chi Lee

    Full Text Available Most live-attenuated tetravalent dengue virus vaccines in current clinical trials are produced from Vero cells. In a previous study we demonstrated that an infectious cDNA clone-derived dengue type 4 (DEN-4 virus retains higher genetic stability in MRC-5 cells than in Vero cells. For this study we investigated two DEN-4 viruses: the infectious cDNA clone-derived DEN-4 2A and its derived 3' NCR 30-nucleotide deletion mutant DEN-4 2AΔ30, a vaccine candidate. Mutations in the C-prM-E, NS2B-NS3, and NS4B-NS5 regions of the DEN genome were sequenced and compared following cell passages in Vero and MRC-5 cells. Our results indicate stronger genetic stability in both viruses following MRC-5 cell passages, leading to significantly lower RNA polymerase error rates when the DEN-4 virus is used for genome replication. Although no significant increases in virus titers were observed following cell passages, DEN-4 2A and DEN-4 2AΔ30 virus titers following Vero cell passages were 17-fold to 25-fold higher than titers following MRC-5 cell passages. Neurovirulence for DEN-4 2A and DEN-4 2AΔ30 viruses increased significantly following passages in Vero cells compared to passages in MRC-5 cells. In addition, more severe DEN-induced hemorrhaging in mice was noted following DEN-4 2A and DEN-4 2AΔ30 passages in Vero cells compared to passages in MRC-5 cells. Target mutagenesis performed on the DEN-4 2A infectious clone indicated that single point mutation of E-Q(438H, E-V(463L, NS2B-Q(78H, and NS2B-A(113T imperatively increased mouse hemorrhaging severity. The relationship between amino acid mutations acquired during Vero cell passage and enhanced DEN-induced hemorrhages in mice may be important for understanding DHF pathogenesis, as well as for the development of live-attenuated dengue vaccines. Taken together, the genetic stability, virus yield, and DEN-induced hemorrhaging all require further investigation in the context of live-attenuated DEN vaccine

  6. 乙肝病毒携带产妇乳汁中乙型肝炎病毒 DNA 载量检测%Hepatitis B virus carrying hepatitis B virus DNA in the parturients load testing

    Institute of Scientific and Technical Information of China (English)

    索淑一

    2013-01-01

    Objective Testing analysis of hepatitis b virus carriers of hepatitis b virus DNA in milk loads, to explore the safety of the hepatitis b virus carriers of breastfeeding, for carrying hepatitis b virus maternal provide reference to choose the right means of feeding. Methods Application of fluorescence quantitative polymerase chain reaction technology, the second liver virus carried in our hospital obstetrics term, 90 cases of maternal serum HBV antigen positive hepatitis b virus DNA in maternal milk loads for testing.applying Results Viral load in the milk of the big 3 this world group and HBV DNA positive rate than small 3 this world, HBsAg, HBcAb positive group, P 0.05. Conclusion Serum HBV - DNA positive maternal milk maternal HBV - DNA tests help guide hepatitis b right choice feeding way, increase the breastfeeding rate as much as possible.%目的:检测分析乙型肝炎病毒携带者乳汁中乙型肝炎病毒DNA载量,探讨乙型肝炎病毒携带者母乳喂养的安全性,为乙肝病毒携带产妇选择合适的喂养方式提供参考。方法应用荧光定量聚合酶链式反应技术,对我院产科足月分娩的乙肝病毒携带产妇90例血清 HBV 抗原阳性产妇乳汁中乙型肝炎病毒 DNA 载量进行检测。结果大三阳组乳汁的病毒载量以及 HBV-DNA 阳性率要高于小三阳组、HBsAg、HBcAb 阳性组,P <0.05。小三阳组乳汁 HBV-DNA 病毒载量以及 HBV-DNA 阳性率与 HBsAg、HBcAb 阳性组相当,P >0.05。结论血清 HBV-DNA 阳性产妇作乳汁 HBV-DNA 检测有助于指导乙肝产妇正确选择喂养方式,尽可能提高母乳喂养率。

  7. A new generation of modified live-attenuated avian influenza viruses using a two-strategy combination as potential vaccine candidates.

    Science.gov (United States)

    Song, Haichen; Nieto, Gloria Ramirez; Perez, Daniel R

    2007-09-01

    In light of the recurrent outbreaks of low pathogenic avian influenza (LPAI) and highly pathogenic avian influenza (HPAI), there is a pressing need for the development of vaccines that allow rapid mass vaccination. In this study, we introduced by reverse genetics temperature-sensitive mutations in the PB1 and PB2 genes of an avian influenza virus, A/Guinea Fowl/Hong Kong/WF10/99 (H9N2) (WF10). Further genetic modifications were introduced into the PB1 gene to enhance the attenuated (att) phenotype of the virus in vivo. Using the att WF10 as a backbone, we substituted neuraminidase (NA) for hemagglutinin (HA) for vaccine purposes. In chickens, a vaccination scheme consisting of a single dose of an att H7N2 vaccine virus at 2 weeks of age and subsequent challenge with the wild-type H7N2 LPAI virus resulted in complete protection. We further extended our vaccination strategy against the HPAI H5N1. In this case, we reconstituted an att H5N1 vaccine virus, whose HA and NA genes were derived from an Asian H5N1 virus. A single-dose immunization in ovo with the att H5N1 vaccine virus in 18-day-old chicken embryos resulted in more than 60% protection for 4-week-old chickens and 100% protection for 9- to 12-week-old chickens. Boosting at 2 weeks posthatching provided 100% protection against challenge with the HPAI H5N1 virus for chickens as young as 4 weeks old, with undetectable virus shedding postchallenge. Our results highlight the potential of live att avian influenza vaccines for mass vaccination in poultry.

  8. Persistent replication of a hepatitis C virus genotype 1b-based chimeric clone carrying E1, E2 and p6 regions from GB virus B in a New World monkey.

    Science.gov (United States)

    Suzuki, Saori; Mori, Ken-Ichi; Higashino, Atsunori; Iwasaki, Yuki; Yasutomi, Yasuhiro; Maki, Noboru; Akari, Hirofumi

    2016-01-01

    The development of effective hepatitis C virus (HCV) vaccines is essential for the prevention of further HCV dissemination, especially in developing countries. Therefore the aim of this study is to establish a feasible and immunocompetent surrogate animal model of HCV infection that will help in evaluation of the protective efficacy of newly developing HCV vaccine candidates. To circumvent the narrow host range of HCV, an HCV genotype 1b-based chimeric clone carrying E1, E2 and p6 regions from GB virus B (GBV-B), which is closely related to HCV, was generated. The chimera between HCV and GBV-B, named HCV/G, replicated more efficiently as compared with the HCV clone in primary marmoset hepatocytes. Furthermore, it was found that the chimera persistently replicated in a tamarin for more than 2 years after intrahepatic inoculation of the chimeric RNA. Although relatively low (virus. Our results will help establish a novel non-human primate model for HCV infection on the basis of the HCV/G chimera in the major framework of the HCV genome.

  9. An occult hepatitis B-derived hepatoma cell line carrying persistent nuclear viral DNA and permissive for exogenous hepatitis B virus infection.

    Science.gov (United States)

    Lin, Chih-Lang; Chien, Rong-Nan; Lin, Shi-Ming; Ke, Po-Yuan; Lin, Chen-Chun; Yeh, Chau-Ting

    2013-01-01

    Occult hepatitis B virus (HBV) infection is defined as persistence of HBV DNA in liver tissues, with or without detectability of HBV DNA in the serum, in individuals with negative serum HBV surface antigen (HBsAg). Despite accumulating evidence suggesting its important clinical roles, the molecular and virological basis of occult hepatitis B remains unclear. In an attempt to establish new hepatoma cell lines, we achieved a new cell line derived from a hepatoma patient with chronic hepatitis C virus (HCV) and occult HBV infection. Characterization of this cell line revealed previously unrecognized properties. Two novel human hepatoma cell lines were established. Hep-Y1 was derived from a male hepatoma patient negative for HCV and HBV infection. Hep-Y2 was derived from a female hepatoma patient suffering from chronic HCV and occult HBV infection. Morphological, cytogenetic and functional studies were performed. Permissiveness to HBV infection was assessed. Both cell lines showed typical hepatocyte-like morphology under phase-contrast and electron microscopy and expressed alpha-fetoprotein, albumin, transferrin, and aldolase B. Cytogenetic analysis revealed extensive chromosomal anomalies. An extrachromosomal form of HBV DNA persisted in the nuclear fraction of Hep-Y2 cells, while no HBsAg was detected in the medium. After treated with 2% dimethyl sulfoxide, both cell lines were permissive for exogenous HBV infection with transient elevation of the replication intermediates in the cytosol with detectable viral antigens by immunoflurescence analysis. In conclusions, we established two new hepatoma cell lines including one from occult HBV infection (Hep-Y2). Both cell lines were permissive for HBV infection. Additionally, Hep-Y2 cells carried persistent extrachromosomal HBV DNA in the nuclei. This cell line could serve as a useful tool to establish the molecular and virological basis of occult HBV infection.

  10. An occult hepatitis B-derived hepatoma cell line carrying persistent nuclear viral DNA and permissive for exogenous hepatitis B virus infection.

    Directory of Open Access Journals (Sweden)

    Chih-Lang Lin

    Full Text Available Occult hepatitis B virus (HBV infection is defined as persistence of HBV DNA in liver tissues, with or without detectability of HBV DNA in the serum, in individuals with negative serum HBV surface antigen (HBsAg. Despite accumulating evidence suggesting its important clinical roles, the molecular and virological basis of occult hepatitis B remains unclear. In an attempt to establish new hepatoma cell lines, we achieved a new cell line derived from a hepatoma patient with chronic hepatitis C virus (HCV and occult HBV infection. Characterization of this cell line revealed previously unrecognized properties. Two novel human hepatoma cell lines were established. Hep-Y1 was derived from a male hepatoma patient negative for HCV and HBV infection. Hep-Y2 was derived from a female hepatoma patient suffering from chronic HCV and occult HBV infection. Morphological, cytogenetic and functional studies were performed. Permissiveness to HBV infection was assessed. Both cell lines showed typical hepatocyte-like morphology under phase-contrast and electron microscopy and expressed alpha-fetoprotein, albumin, transferrin, and aldolase B. Cytogenetic analysis revealed extensive chromosomal anomalies. An extrachromosomal form of HBV DNA persisted in the nuclear fraction of Hep-Y2 cells, while no HBsAg was detected in the medium. After treated with 2% dimethyl sulfoxide, both cell lines were permissive for exogenous HBV infection with transient elevation of the replication intermediates in the cytosol with detectable viral antigens by immunoflurescence analysis. In conclusions, we established two new hepatoma cell lines including one from occult HBV infection (Hep-Y2. Both cell lines were permissive for HBV infection. Additionally, Hep-Y2 cells carried persistent extrachromosomal HBV DNA in the nuclei. This cell line could serve as a useful tool to establish the molecular and virological basis of occult HBV infection.

  11. Porcine circovirus type 2 (PCV2 infection decreases the efficacy of an attenuated classical swine fever virus (CSFV vaccine

    Directory of Open Access Journals (Sweden)

    Huang Yu-Liang

    2011-12-01

    Full Text Available Abstract The Lapinized Philippines Coronel (LPC vaccine, an attenuated strain of classical swine fever virus (CSFV, is an important tool for the prevention and control of CSFV infection and is widely and routinely used in most CSF endemic areas, including Taiwan. The aim of this study was to investigate whether PCV2 infection affects the efficacy of the LPC vaccine. Eighteen 6-week-old, cesarean-derived and colostrum-deprived (CDCD, crossbred pigs were randomly assigned to four groups. A total of 105.3 TCID50 of PCV2 was experimentally inoculated into pigs through both intranasal and intramuscular routes at 0 days post-inoculation (dpi followed by LPC vaccination 12 days later. All the animals were challenged with wild-type CSFV (ALD stain at 27 dpi and euthanized at 45 dpi. Following CSFV challenge, the LPC-vaccinated pigs pre-inoculated with PCV2 showed transient fever, viremia, and viral shedding in the saliva and feces. The number of IgM+, CD4+CD8-CD25+, CD4+CD8+CD25+, and CD4-CD8+CD25+ lymphocyte subsets and the level of neutralizing antibodies against CSFV were significantly higher in the animals with LPC vaccination alone than in the pigs with PCV2 inoculation/LPC vaccination. In addition, PCV2-derived inhibition of the CSFV-specific cell proliferative response of peripheral blood mononuclear cells (PBMCs was demonstrated in an ex vivo experiment. These findings indicate that PCV2 infection decreases the efficacy of the LPC vaccine. This PCV2-derived interference may not only allow the invasion of wild-type CSFV in pig farms but also increases the difficulty of CSF prevention and control in CSF endemic areas.

  12. Live Attenuated Influenza Vaccine Strains Elicit a Greater Innate Immune Response than Antigenically-Matched Seasonal Influenza Viruses during Infection of Human Nasal Epithelial Cell Cultures

    Science.gov (United States)

    Fischer, William A.; Brighton, Missy; Jaspers, Ilona

    2014-01-01

    Influenza viruses are global pathogens that infect approximately 10–20% of the world’s population each year. Vaccines, including the live attenuated influenza vaccine (LAIV), are the best defense against influenza infections. The LAIV is a novel vaccine that actively replicates in the human nasal epithelium and elicits both mucosal and systemic protective immune responses. The differences in replication and innate immune responses following infection of human nasal epithelium with influenza seasonal wild type (WT) and LAIV viruses remain unknown. Using a model of primary differentiated human nasal epithelial cell (hNECs) cultures, we compared influenza WT and antigenically-matched cold adapted (CA) LAIV virus replication and the subsequent innate immune response including host cellular pattern recognition protein expression, host innate immune gene expression, secreted pro-inflammatory cytokine production, and intracellular viral RNA levels. Growth curves comparing virus replication between WT and LAIV strains revealed significantly less infectious virus production during LAIV compared with WT infection. Despite this disparity in infectious virus production the LAIV strains elicited a more robust innate immune response with increased expression of RIG-I, TLR-3, IFNβ, STAT-1, IRF-7, MxA, and IP-10. There were no differences in cytotoxicity between hNEC cultures infected with WT and LAIV strains as measured by basolateral levels of LDH. Elevated levels of intracellular viral RNA during LAIV as compared with WT virus infection of hNEC cultures at 33°C may explain the augmented innate immune response via the up-regulation of pattern recognition receptors and down-stream type I IFN expression. Taken together our results suggest that the decreased replication of LAIV strains in human nasal epithelial cells is associated with a robust innate immune response that differs from infection with seasonal influenza viruses, limits LAIV shedding and plays a role in the

  13. Live attenuated influenza vaccine strains elicit a greater innate immune response than antigenically-matched seasonal influenza viruses during infection of human nasal epithelial cell cultures.

    Science.gov (United States)

    Fischer, William A; Chason, Kelly D; Brighton, Missy; Jaspers, Ilona

    2014-03-26

    Influenza viruses are global pathogens that infect approximately 10-20% of the world's population each year. Vaccines, including the live attenuated influenza vaccine (LAIV), are the best defense against influenza infections. The LAIV is a novel vaccine that actively replicates in the human nasal epithelium and elicits both mucosal and systemic protective immune responses. The differences in replication and innate immune responses following infection of human nasal epithelium with influenza seasonal wild type (WT) and LAIV viruses remain unknown. Using a model of primary differentiated human nasal epithelial cell (hNECs) cultures, we compared influenza WT and antigenically-matched cold adapted (CA) LAIV virus replication and the subsequent innate immune response including host cellular pattern recognition protein expression, host innate immune gene expression, secreted pro-inflammatory cytokine production, and intracellular viral RNA levels. Growth curves comparing virus replication between WT and LAIV strains revealed significantly less infectious virus production during LAIV compared with WT infection. Despite this disparity in infectious virus production the LAIV strains elicited a more robust innate immune response with increased expression of RIG-I, TLR-3, IFNβ, STAT-1, IRF-7, MxA, and IP-10. There were no differences in cytotoxicity between hNEC cultures infected with WT and LAIV strains as measured by basolateral levels of LDH. Elevated levels of intracellular viral RNA during LAIV as compared with WT virus infection of hNEC cultures at 33°C may explain the augmented innate immune response via the up-regulation of pattern recognition receptors and down-stream type I IFN expression. Taken together our results suggest that the decreased replication of LAIV strains in human nasal epithelial cells is associated with a robust innate immune response that differs from infection with seasonal influenza viruses, limits LAIV shedding and plays a role in the silent

  14. Evaluation of live attenuated H7N3 and H7N7 vaccine viruses for their receptor binding preferences, immunogenicity in ferrets and cross reactivity to the novel H7N9 virus.

    Directory of Open Access Journals (Sweden)

    Qi Xu

    Full Text Available Live attenuated influenza vaccine (LAIV candidates of the H7 subtype, A/Netherlands/219/03 (H7N7, NL03 ca and A/chicken/British Columbia/CN-6/2004 (H7N3, BC04 ca, were evaluated for their receptor binding specificity and immunogenicity in ferrets. The BC04 ca virus exhibited α2,3-SA and α2,6-SA dual receptor binding preference while the NL03 ca virus preferentially bound to α2,3-SA. Substitution of the Q226 and G228 (Q-G by the L226 and S228 (L-S residues in the HA improved binding to α2,6-SA for NL03 ca. The vaccine viruses with L-S retained the attenuation phenotype. NL03 L-S ca replicated more efficiently than the original NL03 ca virus in the upper respiratory tract of ferrets, and induced higher levels of humoral and cellular immune responses. Prior vaccination with seasonal LAIV reduced H7-specific antibody responses, but did not reduce the H7N7 vaccine mediated protection against a heterologous H7N3 BC04 wt virus infection in ferrets. In addition, the H7N3 and H7N7 vaccine immunized ferret sera cross reacted with the newly emerged H7N9 virus. These data, in combination with the safety data from previously conducted Phase 1 studies, suggest that these vaccines may have a role in responding to the threat posed by the H7N9 virus.

  15. Kissing-loop interaction between 5' and 3' ends of tick-borne Langat virus genome 'bridges the gap' between mosquito- and tick-borne flaviviruses in mechanisms of viral RNA cyclization: applications for virus attenuation and vaccine development.

    Science.gov (United States)

    Tsetsarkin, Konstantin A; Liu, Guangping; Shen, Kui; Pletnev, Alexander G

    2016-04-20

    Insertion of microRNA target sequences into the flavivirus genome results in selective tissue-specific attenuation and host-range restriction of live attenuated vaccine viruses. However, previous strategies for miRNA-targeting did not incorporate a mechanism to prevent target elimination under miRNA-mediated selective pressure, restricting their use in vaccine development. To overcome this limitation, we developed a new approach for miRNA-targeting of tick-borne flavivirus (Langat virus, LGTV) in the duplicated capsid gene region (DCGR). Genetic stability of viruses with DCGR was ensured by the presence of multiple cis-acting elements within the N-terminal capsid coding region, including the stem-loop structure (5'SL6) at the 3' end of the promoter. We found that the 5'SL6 functions as a structural scaffold for the conserved hexanucleotide motif at its tip and engages in a complementary interaction with the region present in the 3' NCR to enhance viral RNA replication. The resulting kissing-loop interaction, common in tick-borne flaviviruses, supports a single pair of cyclization elements (CYC) and functions as a homolog of the second pair of CYC that is present in the majority of mosquito-borne flaviviruses. Placing miRNA targets into the DCGR results in superior attenuation of LGTV in the CNS and does not interfere with development of protective immunity in immunized mice.

  16. Induction of potent CD8+ T-cell responses by novel biodegradable nanoparticles carrying human immunodeficiency virus type 1 gp120.

    Science.gov (United States)

    Wang, Xin; Uto, Tomofumi; Akagi, Takami; Akashi, Mitsuru; Baba, Masanori

    2007-09-01

    The mainstream of recent anti-AIDS vaccines is a prime/boost approach with multiple doses of the target DNA of human immunodeficiency virus type 1 (HIV-1) and recombinant viral vectors. In this study, we have attempted to construct an efficient protein-based vaccine using biodegradable poly(gamma-glutamic acid) (gamma-PGA) nanoparticles (NPs), which are capable of inducing potent cellular immunity. A significant expansion of CD8+ T cells specific to the major histocompatibility complex class I-restricted gp120 epitope was observed in mice intranasally immunized once with gp120-carrying NPs but not with gp120 alone or gp120 together with the B-subunit of cholera toxin. Both the gp120-encapsulating and -immobilizing forms of NPs could induce antigen-specific spleen CD8+ T cells having a functional profile of cytotoxic T lymphocytes. Long-lived memory CD8+ T cells could also be elicited. Although a substantial decay in the effector memory T cells was observed over time in the immunized mice, the central memory T cells remained relatively constant from day 30 to day 238 after immunization. Furthermore, the memory CD8+ T cells rapidly expanded with boosting with the same immunogen. In addition, gamma-PGA NPs were found to be a much stronger inducer of antigen-specific CD8+ T-cell responses than nonbiodegradable polystyrene NPs. Thus, gamma-PGA NPs carrying various HIV-1 antigens may have great potential as a novel priming and/or boosting tool in current vaccination regimens for the induction of cellular immune responses.

  17. PA-X-associated early alleviation of the acute lung injury contributes to the attenuation of a highly pathogenic H5N1 avian influenza virus in mice.

    Science.gov (United States)

    Hu, Jiao; Mo, Yiqun; Gao, Zhao; Wang, Xiaoquan; Gu, Min; Liang, Yanyan; Cheng, Xin; Hu, Shunlin; Liu, Wenbo; Liu, Huimou; Chen, Sujuan; Liu, Xiaowen; Peng, Daxing; Liu, Xiufan

    2016-08-01

    PA-X is a novel discovered accessory protein encoded by the PA mRNA. Our previous study demonstrated that PA-X decreases the virulence of a highly pathogenic H5N1 strain A/Chicken/Jiangsu/k0402/2010 in mice. However, the underlying mechanism of virulence attenuation associated with PA-X is still unknown. In this study, we compared two PA-X-deficient mutant viruses and the parental virus in terms of induction of pathology and manipulation of host response in the mouse lung, stimulation of cell death and PA nuclear accumulation. We first found that down-regulated PA-X expression markedly aggravated the acute lung injury of the infected mice early on day 1 post-infection (p.i.). We then determined that loss of PA-X expression induced higher levels of cytokines, chemokines and complement-derived peptides (C3a and C5a) in the lung, especially at early time point's p.i. In addition, in vitro assays showed that the PA-X-deficient viruses enhanced cell death and increased expression of reactive oxygen species (ROS) in mammalian cells. Moreover, we also found that PA nuclear accumulation of the PA-X-null viruses accelerated in MDCK cells. These results demonstrate that PA-X decreases the level of complement components, ROS, cell death and inflammatory response, which may together contribute to the alleviated lung injury and the attenuation of the virulence of H5N1 virus in mice.

  18. Novel treatment for lithium-induced nephrogenic diabetes insipidus rat model using the Sendai-virus vector carrying aquaporin 2 gene.

    Science.gov (United States)

    Suga, Hidetaka; Nagasaki, Hiroshi; Kondo, Taka-Aki; Okajima, Yoshiki; Suzuki, Chizuko; Ozaki, Nobuaki; Arima, Hiroshi; Yamamoto, Tokunori; Ozaki, Noriyuki; Akai, Masaro; Sato, Aiko; Uozumi, Nobuyuki; Inoue, Makoto; Hasegawa, Mamoru; Oiso, Yutaka

    2008-11-01

    Congenital nephrogenic diabetes insipidus (NDI) is a chronic disorder involving polyuria and polydipsia that results from unresponsiveness of the renal collecting ducts to the antidiuretic hormone vasopressin. Either of the genetic defects in vasopressin V2 receptor or the water channel aquaporin 2 (AQP2) cause the disease, which interfere the water reabsorption at the epithelium of the collecting duct. An unconscious state including a perioperative situation can be life threatening because of the difficulty to regulate their water balance. The Sendai virus (SeV) vector system deleting fusion protein (F) gene (SeV/DeltaF) is considered most suitable because of the short replication cycle and nontransmissible character. An animal model for NDI with reduced AQP2 by lithium chloride was used to develop the therapy. When the SeV/DeltaF vector carrying a human AQP2 gene (AQP2-SeV/DeltaF) was administered retrogradely via ureter to renal pelvis, AQP2 was expressed in the renal collecting duct to reduce urine output and water intake by up to 40%. In combination with the retorograde administration to pelvis, this system could be the cornerstone for the applicable therapies on not only NDI patients but also other diseases associate with the medullary collecting duct.

  19. Attenuation and efficacy of human parainfluenza virus type 1 (HPIV1 vaccine candidates containing stabilized mutations in the P/C and L genes

    Directory of Open Access Journals (Sweden)

    Skiadopoulos Mario H

    2007-07-01

    Full Text Available Abstract Background Two recombinant, live attenuated human parainfluenza virus type 1 (rHPIV1 mutant viruses have been developed, using a reverse genetics system, for evaluation as potential intranasal vaccine candidates. These rHPIV1 vaccine candidates have two non-temperature sensitive (non-ts attenuating (att mutations primarily in the P/C gene, namely CR84GHNT553A (two point mutations used together as a set and CΔ170 (a short deletion mutation, and two ts att mutations in the L gene, namely LY942A (a point mutation, and LΔ1710–11 (a short deletion, the last of which has not been previously described. The latter three mutations were specifically designed for increased genetic and phenotypic stability. These mutations were evaluated on the HPIV1 backbone, both individually and in combination, for attenuation, immunogenicity, and protective efficacy in African green monkeys (AGMs. Results The rHPIV1 mutant bearing the novel LΔ1710–11 mutation was highly ts and attenuated in AGMs and was immunogenic and efficacious against HPIV1 wt challenge. The rHPIV1-CR84G/Δ170HNT553ALY942A and rHPIV1-CR84G/Δ170HNT553ALΔ1710–11 vaccine candidates were highly ts, with shut-off temperatures of 38°C and 35°C, respectively, and were highly attenuated in AGMs. Immunization with rHPIV1-CR84G/Δ170HNT553ALY942A protected against HPIV1 wt challenge in both the upper and lower respiratory tracts. In contrast, rHPIV1-CR84G/Δ170HNT553ALΔ1710–11 was not protective in AGMs due to over-attenuation, but it is expected to replicate more efficiently and be more immunogenic in the natural human host. Conclusion The rHPIV1-CR84G/Δ170HNT553ALY942A and rHPIV1-CR84G/Δ170HNT553ALΔ1710–11 vaccine candidates are clearly highly attenuated in AGMs and clinical trials are planned to address safety and immunogenicity in humans.

  20. The genomes of Marek’s disease virus exist as quasispecies at defined intervals during serial passage-induced attenuation

    Science.gov (United States)

    Marek’s disease (MD) is a lymphoproliferative disease of chickens caused by gallid herpesvirus type 2 (GaHV-2). The disease is controlled through mass vaccination with live-attenuated strains. Attenuation of oncogenic GaHV-2 involves the serial passage of a virulent field isolate in avian embryo fib...

  1. Envelope Protein Mutations L107F and E138K Are Important for Neurovirulence Attenuation for Japanese Encephalitis Virus SA14-14-2 Strain

    Directory of Open Access Journals (Sweden)

    Jian Yang

    2017-01-01

    Full Text Available The attenuated Japanese encephalitis virus (JEV strain SA14-14-2 has been successfully utilized to prevent JEV infection; however, the attenuation determinants have not been fully elucidated. The envelope (E protein of the attenuated JEV SA14-14-2 strain differs from that of the virulent parental SA14 strain at eight amino acid positions (E107, E138, E176, E177, E264, E279, E315, and E439. Here, we investigated the SA14-14-2-attenuation determinants by mutating E107, E138, E176, E177, and E279 in SA14-14-2 to their status in the parental virulent strain and tested the replication capacity, neurovirulence, neuroinvasiveness, and mortality associated with the mutated viruses in mice, as compared with those of JEV SA14-14-2 and SA14. Our findings indicated that revertant mutations at the E138 or E107 position significantly increased SA14-14-2 virulence, whereas other revertant mutations exhibited significant increases in neurovirulence only when combined with E138, E107, and other mutations. Revertant mutations at all eight positions in the E protein resulted in the highest degree of SA14-14-2 virulence, although this was still lower than that observed in SA14. These results demonstrated the critical role of the viral E protein in controlling JEV virulence and identified the amino acids at the E107 and E138 positions as the key determinants of SA14-14-2 neurovirulence.

  2. Development of a human live attenuated West Nile infectious DNA vaccine: Suitability of attenuating mutations found in SA14-14-2 for WN vaccine design.

    Science.gov (United States)

    Yamshchikov, Vladimir; Manuvakhova, Marina; Rodriguez, Efrain

    2016-01-01

    Direct attenuation of West Nile (WN) virus strain NY99 for the purpose of vaccine development is not feasible due to its high virulence and pathogenicity. Instead, we created highly attenuated chimeric virus W1806 with the serological identity of NY99. To further attenuate W1806, we investigated effects of mutations found in Japanese encephalitis virus vaccine SA14-14-2. WN viruses carrying all attenuating mutations lost infectivity in mammalian, but not in mosquito cells. No single reversion restored infectivity in mammalian cells, although increased infectivity in mosquito cells was observed. To identify a subset of mutations suitable for further attenuation of W1806, we analyzed effects of E138K and K279M changes on virulence, growth properties, and immunogenicity of derivatized W956, from which chimeric W1806 inherited its biological properties and attenuation profile. Despite strong dominant attenuating effect, introduction of only two mutations was not sufficient for attenuating W1806 to the safety level acceptable for human use.

  3. Protection of Cattle against Rinderpest by Vaccination with Wild-Type but Not Attenuated Strains of Peste des Petits Ruminants Virus

    Science.gov (United States)

    Holzer, Barbara; Hodgson, Sophia; Logan, Nicola; Willett, Brian

    2016-01-01

    ABSTRACT Although rinderpest virus (RPV) has been eradicated in the wild, efforts are still continuing to restrict the extent to which live virus is distributed in facilities around the world and to prepare for any reappearance of the disease, whether through deliberate or accidental release. In an effort to find an alternative vaccine which could be used in place of the traditional live attenuated RPV strains, we have determined whether cattle can be protected from rinderpest by inoculation with vaccine strains of the related morbillivirus, peste des petits ruminants virus (PPRV). Cattle were vaccinated with wild-type PPRV or either of two established PPRV vaccine strains, Nigeria/75/1 or Sungri/96. All animals developed antibody and T cell immune responses to the inoculated PPRV. However, only the animals given wild-type PPRV were protected from RPV challenge. Animals given PPRV/Sungri/96 were only partially protected, and animals given PPRV/Nigeria/75/1 showed no protection against RPV challenge. While sera from animals vaccinated with the vaccine strain of RPV showed cross-neutralizing ability against PPRV, none of the sera from animals vaccinated with any strain of PPRV was able to neutralize RPV although sera from animals inoculated with wild-type PPRV were able to neutralize RPV-pseudotyped vesicular stomatitis virus. IMPORTANCE Rinderpest virus has been eradicated, and it is only the second virus for which this is so. Significant efforts are still required to ensure preparedness for a possible escape of RPV from a laboratory or its deliberate release. Since RPV vaccine protects sheep and goats from PPRV, it is important to determine if the reverse is true as this would provide a non-RPV vaccine for dealing with suspected RPV outbreaks. This is probably the last in vivo study with live RPV that will be approved. PMID:26984722

  4. Neutralizing Antibody Responses to Antigenically Drifted Influenza A(H3N2) Viruses among Children and Adolescents following 2014-2015 Inactivated and Live Attenuated Influenza Vaccination

    Science.gov (United States)

    Martin, Judith M.; Gross, F. Liaini; Jefferson, Stacie; Cole, Kelly Stefano; Archibald, Crystal Ann; Nowalk, Mary Patricia; Susick, Michael; Moehling, Krissy; Spencer, Sarah; Chung, Jessie R.; Flannery, Brendan; Zimmerman, Richard K.

    2016-01-01

    Human influenza A(H3N2) viruses that predominated during the moderately severe 2014-2015 influenza season differed antigenically from the vaccine component, resulting in reduced vaccine effectiveness (VE). To examine antibody responses to 2014-2015 inactivated influenza vaccine (IIV) and live-attenuated influenza vaccine (LAIV) among children and adolescents, we collected sera before and after vaccination from 150 children aged 3 to 17 years enrolled at health care facilities. Hemagglutination inhibition (HI) assays were used to assess the antibody responses to vaccine strains. We evaluated cross-reactive antibody responses against two representative A(H3N2) viruses that had antigenically drifted from the A(H3N2) vaccine component using microneutralization (MN) assays. Postvaccination antibody titers to drifted A(H3N2) viruses were higher following receipt of IIV (MN geometric mean titers [GMTs], 63 to 68; 38 to 45% achieved seroconversion) versus LAIV (MN GMT, 22; only 3 to 5% achieved seroconversion). In 9- to 17-year-olds, the highest MN titers were observed among IIV-vaccinated individuals who had received LAIV in the previous season. Among all IIV recipients aged 3 to 17 years, the strongest predictor of antibody responses to the drifted viruses was the prevaccination titers to the vaccine strain. The results of our study suggest that in an antigenically drifted influenza season, vaccination still induced cross-reactive antibody responses to drifted circulating A(H3N2) viruses, although higher antibody titers may be required for protection. Antibody responses to drifted A(H3N2) viruses following vaccination were influenced by multiple factors, including vaccine type and preexisting immunity from prior exposure. PMID:27558294

  5. Recoding classical swine fever virus (CSFV) structural glycoprotein E2 produces complete virus attenuation in swine and protects infected animals against disease

    Science.gov (United States)

    Controlling classical swine fever (CSF) involves vaccination in endemic regions and preemptive slaughter of infected swine herds during epidemics. Generally, live attenuated vaccines induce solid immunity. Using diverse approaches, reverse genetics has been useful in developing classical swine fever...

  6. Persistence of attenuated HIV-1 rev alleles in an epidemiologically linked cohort of long-term survivors infected with nef-deleted virus

    Directory of Open Access Journals (Sweden)

    Wesselingh Steven L

    2007-07-01

    Full Text Available Abstract Background The Sydney blood bank cohort (SBBC of long-term survivors consists of multiple individuals infected with nef-deleted, attenuated strains of human immunodeficiency virus type 1 (HIV-1. Although the cohort members have experienced differing clinical courses and now comprise slow progressors (SP as well as long-term nonprogressors (LTNP, longitudinal analysis of nef/long-terminal repeat (LTR sequences demonstrated convergent nef/LTR sequence evolution in SBBC SP and LTNP. Thus, the in vivo pathogenicity of attenuated HIV-1 strains harboured by SBBC members is dictated by factors other than nef/LTR. Therefore, to determine whether defects in other viral genes contribute to attenuation of these HIV-1 strains, we characterized dominant HIV-1 rev alleles that persisted in 4 SBBC subjects; C18, C64, C98 and D36. Results The ability of Rev derived from D36 and C64 to bind the Rev responsive element (RRE in RNA binding assays was reduced by approximately 90% compared to Rev derived from HIV-1NL4-3, C18 or C98. D36 Rev also had a 50–60% reduction in ability to express Rev-dependent reporter constructs in mammalian cells. In contrast, C64 Rev had only marginally decreased Rev function despite attenuated RRE binding. In D36 and C64, attenuated RRE binding was associated with rare amino acid changes at 3 highly conserved residues; Gln to Pro at position 74 immediately N-terminal to the Rev activation domain, and Val to Leu and Ser to Pro at positions 104 and 106 at the Rev C-terminus, respectively. In D36, reduced Rev function was mapped to an unusual 13 amino acid extension at the Rev C-terminus. Conclusion These findings provide new genetic and mechanistic insights important for Rev function, and suggest that Rev function, not Rev/RRE binding may be rate limiting for HIV-1 replication. In addition, attenuated rev alleles may contribute to viral attenuation and long-term survival of HIV-1 infection in a subset of SBBC members.

  7. [Effect of Low Dose of Chicken Infectious Anemia Virus in Attenuated Vaccine on SPF Chicken Body Weight and Vaccine Immune Antibody].

    Science.gov (United States)

    Fang, Lichun; Li, Xiaohan; Ren, Zhihao; Li, Yang; Wang, Yixin; Cui, Zhizhong; Chang, Shuang; Zhao, Peng

    2016-03-01

    In order to observe the effect of the immune and weight of chickens after use the attenuated vaccine with low dose of chicken infectious anemia virus (CIAV). In this study, the effects of low dose of CIAV on the weight of SPF chickens and NDV antibody production were observed by simulated experiments. The results showed that 10 EID50 and 5 EID50 CIAV per plume attenuated NDV vaccines were used to cause the weight loss of SPF chickens. Compared with the use of the non contaminated vaccine group, it has significant difference. And NDV antibody levels compared with the use of the non contaminated groups also decreased after use the vaccine with two doses of CIAV contaminated. It has significant difference. A certain proportion of CIAV antibody positive was detected at the beginning of the second week after use the NDV vaccine with two doses of CIAV contaminated. The detection of a high proportion of CIAV nucleic acid was detected in the first week after the use of a contaminated vaccine. The results of the study demonstrate the effects of CIAV pollution on the production and immune function of SPF chickens, and it is suggested that increasing the detection of viral nucleic acid can help save time and improve the detection rate in the detection of exogenous virus contamination by SPF chicken test method.

  8. Identification of differentially expressed proteins in porcine alveolar macrophages infected with virulent/attenuated strains of porcine reproductive and respiratory syndrome virus.

    Directory of Open Access Journals (Sweden)

    Yan-Jun Zhou

    Full Text Available The highly pathogenic porcine reproductive and respiratory syndrome virus (HP-PRRSV is still a serious threat to the swine industry. However, the pathogenic mechanism of HP-PRRSV remains unclear. We infected host porcine alveolar macrophages (PAMs with the virulent HuN4 strain and the attenuated HuN4-F112 strain and then utilized fluorescent two-dimensional difference gel electrophoresis (2D-DIGE to screen for intracellular proteins that were differentially expressed in host cells infected with the two strains. There were 153 proteins with significant different expression (P<0.01 observed, 42 of which were subjected to mass spectrometry, and 24 proteins were identified. PAM cells infected with the virulent strain showed upregulated expression of pyruvate kinase M2 (PKM2, heat shock protein beta-1 (HSPB1, and proteasome subunit alpha type 6 (PSMA6, which were downregulated in cells infected with the attenuated strain. The upregulation of PKM2 provides sufficient energy for viral replication, and the upregulation of HSPB1 inhibits host cell apoptosis and therefore facilitates mass replication of the virulent strain, while the upregulation of PSMA6 facilitates the evasion of immune surveillance by the virus. Studying on those molecules mentioned above may be able to help us to understand some unrevealed details of HP-PRRSV infection, and then help us to decrease its threat to the swine industry in the future.

  9. Immune-driven adaptation of hepatitis B virus genotype D involves preferential alteration in B-cell epitopes and replicative attenuation--an insight from human immunodeficiency virus/hepatitis B virus coinfection.

    Science.gov (United States)

    Mondal, R K; Khatun, M; Ghosh, S; Banerjee, P; Datta, S; Sarkar, S; Saha, B; Santra, A; Banerjee, S; Chowdhury, A; Datta, S

    2015-07-01

    An important driving force behind the sequence diversity of hepatitis B virus (HBV) is viral adaptation to host immune responses. To gain an insight into the impact of host immunity on genetic diversification and properties of HBV, we characterized HBV of genotype D from treatment-naive hepatitis B e antigen-positive (EP) and hepatitis B e antigen-negative (EN) patients with chronic hepatitis B (CHB), where HBV is under stronger immune pressure, with that of HBV derived from human immunodeficiency virus (HIV)/HBV-coinfected individuals, where HIV infection has significantly weakened the immune system. Full-length sequence analysis showed that HBV heterogeneity was most extensive in EN-CHB followed by EP-CHB and HIV/HBV coinfection. The relative magnitude of non-synonymous changes within B-cell epitopes was greater than that in T-cell epitopes of HBV open reading frames (ORFs) in both EP-CHB and EN-CHB. Nine amino acid substitutions were identified in B-cell epitopes and one in a T-cell epitope of HBV in EN-CHB, most of which resulted in altered hydrophobicities, as determined using the Kyte and Doolittle method, relative to wild-type residues found in HBV from the HIV-positive group. Additionally, 19 substitutions occurred at significantly higher frequencies in non-epitope regions of HBV ORF-P in EN-CHB than HIV/HBV-coinfected patients. In vitro replication assay demonstrated that the substitutions, particularly in reverse transcriptase and RNaseH domains of ORF-P, resulted in a decline in replication capacity of HBV. Hence, our results indicate that HBV adapts to increasing immune pressure through preferential mutations in B-cell epitopes and by replicative attenuation. The viral epitopes linked to immune response identified in this study bear important implications for future HBV vaccine studies.

  10. Immunogenicity of viral vector, prime-boost SIV vaccine regimens in infant rhesus macaques: attenuated vesicular stomatitis virus (VSV) and modified vaccinia Ankara (MVA) recombinant SIV vaccines compared to live-attenuated SIV.

    Science.gov (United States)

    Van Rompay, Koen K A; Abel, Kristina; Earl, Patricia; Kozlowski, Pamela A; Easlick, Juliet; Moore, Joseph; Buonocore-Buzzelli, Linda; Schmidt, Kimberli A; Wilson, Robert L; Simon, Ian; Moss, Bernard; Rose, Nina; Rose, John; Marthas, Marta L

    2010-02-10

    In a previously developed infant macaque model mimicking HIV infection by breast-feeding, we demonstrated that intramuscular immunization with recombinant poxvirus vaccines expressing simian immunodeficiency virus (SIV) structural proteins provided partial protection against infection following oral inoculation with virulent SIV. In an attempt to further increase systemic but also local antiviral immune responses at the site of viral entry, we tested the immunogenicity of different orally administered, replicating vaccines. One group of newborn macaques received an oral prime immunization with a recombinant vesicular stomatitis virus expressing SIVmac239 gag, pol and env (VSV-SIVgpe), followed 2 weeks later by an intramuscular boost immunization with MVA-SIV. Another group received two immunizations with live-attenuated SIVmac1A11, administered each time both orally and intravenously. Control animals received mock immunizations or non-SIV VSV and MVA control vectors. Analysis of SIV-specific immune responses in blood and lymphoid tissues at 4 weeks of age demonstrated that both vaccine regimens induced systemic antibody responses and both systemic and local cell-mediated immune responses. The safety and immunogenicity of the VSV-SIVgpe+MVA-SIV immunization regimen described in this report provide the scientific incentive to explore the efficacy of this vaccine regimen against virulent SIV exposure in the infant macaque model.

  11. An attenuated herpes simplex virus type 1 (HSV1 encoding the HIV-1 Tat protein protects mice from a deadly mucosal HSV1 challenge.

    Directory of Open Access Journals (Sweden)

    Mariaconcetta Sicurella

    Full Text Available Herpes simplex virus types 1 and 2 (HSV1 and HSV2 are common infectious agents in both industrialized and developing countries. They cause recurrent asymptomatic and/or symptomatic infections, and life-threatening diseases and death in newborns and immunocompromised patients. Current treatment for HSV relies on antiviral medications, which can halt the symptomatic diseases but cannot prevent the shedding that occurs in asymptomatic patients or, consequently, the spread of the viruses. Therefore, prevention rather than treatment of HSV infections has long been an area of intense research, but thus far effective anti-HSV vaccines still remain elusive. One of the key hurdles to overcome in anti-HSV vaccine development is the identification and effective use of strategies that promote the emergence of Th1-type immune responses against a wide range of epitopes involved in the control of viral replication. Since the HIV1 Tat protein has several immunomodulatory activities and increases CTL recognition of dominant and subdominant epitopes of heterologous antigens, we generated and assayed a recombinant attenuated replication-competent HSV1 vector containing the tat gene (HSV1-Tat. In this proof-of-concept study we show that immunization with this vector conferred protection in 100% of mice challenged intravaginally with a lethal dose of wild-type HSV1. We demonstrate that the presence of Tat within the recombinant virus increased and broadened Th1-like and CTL responses against HSV-derived T-cell epitopes and elicited in most immunized mice detectable IgG responses. In sharp contrast, a similarly attenuated HSV1 recombinant vector without Tat (HSV1-LacZ, induced low and different T cell responses, no measurable antibody responses and did not protect mice against the wild-type HSV1 challenge. These findings strongly suggest that recombinant HSV1 vectors expressing Tat merit further investigation for their potential to prevent and/or contain HSV1

  12. Replacement of the Ectodomains of the Hemagglutinin-Neuraminidase and Fusion Glycoproteins of Recombinant Parainfluenza Virus Type 3 (PIV3) with Their Counterparts from PIV2 Yields Attenuated PIV2 Vaccine Candidates

    OpenAIRE

    Tao, Tao; Skiadopoulos, Mario H.; Davoodi, Fatemeh; Riggs, Jeffrey M.; Collins, Peter L.; Murphy, Brian R

    2000-01-01

    We sought to develop a live attenuated parainfluenza virus type 2 (PIV2) vaccine strain for use in infants and young children, using reverse genetic techniques that previously were used to rapidly produce a live attenuated PIV1 vaccine candidate. The PIV1 vaccine candidate, designated rPIV3-1cp45, was generated by substituting the full-length HN and F proteins of PIV1 for those of PIV3 in the attenuated cp45 PIV3 vaccine candidate (T. Tao et al., J. Virol. 72:2955–2961, 1998; M. H. Skiadopoul...

  13. Immunization of African Indigenous Pigs with Attenuated Genotype I African Swine Fever Virus OURT88/3 Induces Protection Against Challenge with Virulent Strains of Genotype I.

    Science.gov (United States)

    Mulumba-Mfumu, L K; Goatley, L C; Saegerman, C; Takamatsu, H-H; Dixon, L K

    2016-10-01

    The attenuated African swine fever virus genotype I strain OURT88/3 has previously been shown to induce protection of European breeds of domestic pigs against challenge with virulent isolates. To determine whether protective immune responses could also be induced in indigenous breeds of pigs from the Kinshassa region in Democratic Republic of Congo, we immunized a group of eight pigs with OURT88/3 strain and challenged the pigs 3 weeks later with virulent genotype I strain OURT88/1. Four of the pigs were protected against challenge. Three of the eight pigs died from African swine fever virus and a fourth from an unknown cause. The remaining four pigs all survived challenge with a recent virulent genotype I strain from the Democratic Republic of Congo, DRC 085/10. Control groups of non-immune pigs challenged with OURT88/1 or DRC 085/10 developed signs of acute ASFV as expected and had high levels of virus genome in blood.

  14. Immunogenic and replicative properties of classical swine fever virus replicon particles modified to induce IFN-α/β and carry foreign genes.

    Science.gov (United States)

    Suter, Rolf; Summerfield, Artur; Thomann-Harwood, Lisa J; McCullough, Kenneth C; Tratschin, Jon-Duri; Ruggli, Nicolas

    2011-02-04

    Virus replicon particles (VRP) are genetically engineered infectious virions incapable of generating progeny virus due to partial or complete deletion of at least one structural gene. VRP fulfil the criteria of a safe vaccine and gene delivery system. With VRP derived from classical swine fever virus (CSF-VRP), a single intradermal vaccination protects from disease. Spreading of the challenge virus in the host is however not completely abolished. Parameters that are critical for immunogenicity of CSF-VRP are not well characterized. Considering the importance of type I interferon (IFN-α/β) to immune defence development, we generated IFN-α/β-inducing VRP to determine how this would influence vaccine efficacy. We also evaluated the effect of co-expressing granulocyte macrophage colony-stimulating factor (GM-CSF) in the vaccine context. The VRP were capable of long-term replication in cell culture despite the presence of IFN-α/β. In vivo, RNA replication was essential for the induction of an immune response. IFN-α/β-inducing and GM-CSF-expressing CSF-VRP were similar to unmodified VRP in terms of antibody and peripheral T-cell responses, and in reducing the blood levels of challenge virus RNA. Importantly, the IFN-α/β-inducing VRP did show increased efficacy over the unmodified VRP in terms of B-cell and T-cell responses, when tested with secondary immune responses by in vitro restimulation assay.

  15. 牛病毒性腹泻病二价弱毒活疫苗制备工艺研究%Study on Preparation Technique of Divalent Attenuated Virus Live Vaccine of Bovine Viral Diarrhea Virus

    Institute of Scientific and Technical Information of China (English)

    李海涛; 苗利光; 刘艳环; 朱言柱; 安亚雄; 王坤; 冯卓

    2013-01-01

    研究了BVDV2/JZ05-1和BVDV1/JZ05-3二价弱毒活疫苗的制备工艺.通过对BVDV2/JZ05-1和BVDV1/JZ05-3疫苗毒传代培养测定毒价后,试制出5批毒价分别是10.4TCID50/mL和105.6TCID50/mL的BVDV二价弱毒活疫苗,经检验符合试验设计要求.%The aim of this study was to explore the preparation technique of divalent attenuated virus live vaccine of bovine viral diarrhea virus 2/JZ05-1(BVDV2/JZ05-1) and BVDV1/JZ05-3.BVDV2/JZ05-1 and BVDV1/JZ05-3 were continuously cultivated in cell culture.The poison titor was examined.5 groups of divalent attenuated BVDV live vaccine were produced.The poison prices were 105.4TCID50/mL and 105.6TCID50/mL,respectively.The vaccines were examined and was within the range of the test design requirement.

  16. Immunization of pigs with an attenuated pseudorabies virus recombinant expressing the haemagglutinin of pandemic swine origin H1N1 influenza A virus.

    Science.gov (United States)

    Klingbeil, Katharina; Lange, Elke; Teifke, Jens P; Mettenleiter, Thomas C; Fuchs, Walter

    2014-04-01

    Pigs can be severely harmed by influenza, and represent important reservoir hosts, in which new human pathogens such as the recent pandemic swine-origin H1N1 influenza A virus can arise by mutation and reassortment of genome segments. To obtain novel, safe influenza vaccines for pigs, and to investigate the antigen-specific immune response, we modified an established live-virus vaccine against Aujeszky's disease of swine, pseudorabies virus (PrV) strain Bartha (PrV-Ba), to serve as vector for the expression of haemagglutinin (HA) of swine-origin H1N1 virus. To facilitate transgene insertion, the genome of PrV-Ba was cloned as a bacterial artificial chromosome. HA expression occurred under control of the human or murine cytomegalovirus immediate early promoters (P-HCMV, P-MCMV), but could be substantially enhanced by synthetic introns and adaptation of the codon usage to that of PrV. However, despite abundant expression, the heterologous glycoprotein was not detectably incorporated into mature PrV particles. Replication of HA-expressing PrV in cell culture was only slightly affected compared to that of the parental virus strain. A single immunization of pigs with the PrV vector expressing the codon-optimized HA gene under control of P-MCMV induced high levels of HA-specific antibodies. The vaccinated animals were protected from clinical signs after challenge with a related swine-origin H1N1 influenza A virus, and challenge virus shedding was significantly reduced.

  17. Protection of pigs against pandemic swine origin H1N1 influenza A virus infection by hemagglutinin- or neuraminidase-expressing attenuated pseudorabies virus recombinants.

    Science.gov (United States)

    Klingbeil, Katharina; Lange, Elke; Blohm, Ulrike; Teifke, Jens P; Mettenleiter, Thomas C; Fuchs, Walter

    2015-03-01

    Influenza is an important respiratory disease of pigs, and may lead to novel human pathogens like the 2009 pandemic H1N1 swine-origin influenza virus (SoIV). Therefore, improved influenza vaccines for pigs are required. Recently, we demonstrated that single intranasal immunization with a hemagglutinin (HA)-expressing pseudorabies virus recombinant of vaccine strain Bartha (PrV-Ba) protected pigs from H1N1 SoIV challenge (Klingbeil et al., 2014). Now we investigated enhancement of efficacy by prime-boost vaccination and/or intramuscular administration. Furthermore, a novel PrV-Ba recombinant expressing codon-optimized N1 neuraminidase (NA) was included. In vitro replication of this virus was only slightly affected compared to parental virus. Unlike HA, the abundantly expressed NA was efficiently incorporated into PrV particles. Immunization of pigs with the two PrV recombinants, either singly or in combination, induced B cell proliferation and the expected SoIV-specific antibodies, whose titers increased substantially after boost vaccination. After immunization of animals with either PrV recombinant H1N1 SoIV challenge virus replication was significantly reduced compared to PrV-Ba vaccinated or naïve controls. Protective efficacy of HA-expressing PrV was higher than of NA-expressing PrV, and not significantly enhanced by combination. Despite higher serum antibody titers obtained after intramuscular immunization, transmission of challenge virus to naïve contact animals was only prevented after intranasal prime-boost vaccination with HA-expressing PrV-Ba.

  18. Construction and characterization of a new simian/human immunodeficiency viruses clone carrying an env gene derived from a CRF07_BC strain

    Institute of Scientific and Technical Information of China (English)

    LI Yue; YANG Gui-bo; CHEN Qi-min; LIU Qiang; MENG Zhe-feng; GENG Yun-qi; QIAO Wen-tao; SHAO Yi-ming

    2009-01-01

    Background The CRF07_BC recombinant strain has been one of the most predominantly circulated HIV-1 strains in China, it is therefore necessary and urgent to develop a relevant animal model to evaluate candidate vaccines targeting HIV-1 CRF07_BC. A highly replication-competent simian/human immunodeficiency viruses (SHIV) construct containing the Chinese CRF07_BC HIV-1 env gene with the ability to infect Chinese rhesus monkeys would serve as an important tool in the development of HIV vaccines. The aim of this study was to examine whether SHIV XJDC6431 with the env fragment from a Chinese HIV-1 isolate virus could infect the human and monkey peripheral blood mononuclear cell (PBMC), establish infection in Chinese rhesus macaque.Methods A SHIV strain was constructed by replacing the rev/env genes of SHIV KB9 with the corresponding fragment derived from the HIV-1 CRF07_BC strain. The infectious activity of the SHIV clones was determined in vitro in PBMCs from both non-human primate animals and humans. Finally, one Chinese rhesus macaques (Macaca mulatto) was infected with one SHIV via intravenous infusion.Results One SHIV clone designated as SHIV XJDC6431, was generated that could infect macaque and human PBMC. The virus produced from this clone also efficiently infected the CCR5-expressing GHOST cell lines, indicating that it uses CCR5 as its coreceptor. Finally, the virus was intravenously inoculated into one Chinese rhesus macaque. Eventually, the animal became infected as shown by the occurrence of viremia within 3 of infection. The viral load reached 10~5 copies of viral RNA per ml of plasma during the acute phase of infection and lasted for 10 weeks post infection. Conclusions We conclude that SHIV XJDC6431 is an R5-tropic chimeric virus, which can establish infection not only in vitro but also in vivo in the Chinese rhesus macaque. Although the animal inoculated with SHIV XJDC6431 became infected without developing a pathologic phenotype, the virus efficiently

  19. Attenuated Salmonella typhimurium delivering DNA vaccine encoding duck enteritis virus UL24 induced systemic and mucosal immune responses and conferred good protection against challenge

    Directory of Open Access Journals (Sweden)

    Yu Xia

    2012-07-01

    Full Text Available Abstract Orally delivered DNA vaccines against duck enteritis virus (DEV were developed using live attenuated Salmonella typhimurium (SL7207 as a carrier and Escherichia coli heat labile enterotoxin B subunit (LTB as a mucosal adjuvant. DNA vaccine plasmids pVAX-UL24 and pVAX-LTB-UL24 were constructed and transformed into attenuated Salmonella typhimurium SL7207 resulting SL7207 (pVAX-UL24 and SL7207 (pVAX-LTB-UL24 respectively. After ducklings were orally inoculated with SL7207 (pVAX-UL24 or SL7207 (pVAX-LTB-UL24, the anti-DEV mucosal and systemic immune responses were recorded. To identify the optimum dose that confers maximum protection, we used different doses of the candidate vaccine SL7207 (pVAX-LTB-UL24 during oral immunization. The strongest mucosal and systemic immune responses developed in the SL7207 (pVAX-LTB-UL24 (1011 CFU immunized group. Accordingly, oral immunization of ducklings with SL7207 (pVAX-LTB-UL24 showed superior efficacy of protection (60-80% against a lethal DEV challenge (1000 LD50, compared with the limited survival rate (40% of ducklings immunized with SL7207 (pVAX-UL24. Our study suggests that the SL7207 (pVAX-LTB-UL24 can be a candidate DEV vaccine.

  20. Diversity (polymorphism) of the meq gene in the attenuated Marek's disease virus (MDV) serotype 1 and MDV-transformed cell lines.

    Science.gov (United States)

    Chang, Kyung-Soo; Ohashi, Kazuhiko; Onuma, Misao

    2002-12-01

    The meq gene encoding a 339-amino-acid bZIP transactivator protein has been identified as a candidate oncogene of Marek's disease virus serotype 1 (MDV1), which induces malignant lymphomas in chickens. We have previously reported that, in addition to meq, L-meq, in which a 180-bp sequence is inserted into the region encoding the transactivation domain of meq, is also detected in chickens experimentally infected with MDV. To further analyze the diversity in meq, PCR was performed using a primer set which specifically amplify the proline-rich repeat (PRR) region in the transactivation domain of meq. In CVI988/R6, a vaccine strain of MDV1, and JM, an MDV1 strain attenuated by prolonged passage in vitro, a major band of a 0.8 kb corresponding to L-meq as well as a minor band of 0.6 kb corresponding to meq was detected by PCR. Furthermore, extra 0.5- and 0.3-kb bands, corresponding to genes termed as short meq (S-meq), and very short meq (VS-meq), respectively, were also detected. These genes were also detected in MDV-transformed cell lines, MSB1 and MTB1. In Md5, an oncogenic MDV1, attenuated by prolonged passage in vitro, the 0.6-kb meq was consistently detected, and 0.5-kb S-meq was occasionally detected. This diversity in meq was due to the difference in the copy number of the PRR region: L-meq and meq contained 9 and 6 copies of PRR while 4 and 2 copies of PRR were present in S-meq and VS-meq, respectively. Thus, the meq gene is polymorphic in the attenuated MDV1 and the MDV-transformed cell lines, and gene products from different meq genes may have different functions from each other.

  1. Risks associated with commodity trade: transmission of viral haemorrhagic septicaemia virus (VHSV) to rainbow trout fry from VHSV-carrying tissue-homogenates.

    Science.gov (United States)

    Oidtmann, B; Joiner, C; Reese, R A; Stone, D; Dodge, M; Dixon, P

    2011-06-01

    Movements of commodity fish present a potential risk of transferring pathogens. Within a study to estimate the risk from imported rainbow trout Oncorhynchus mykiss carcases, fry were exposed to tissue homogenates from market size rainbow trout infected experimentally with viral haemorrhagic septicaemia (VHS) by waterborne exposure to VHS virus (VHSV, isolate of genotype Ia). Tissues were collected from fish that showed clinical signs and from recent mortalities. Homogenates of (i) internal organs, (ii) brain/gills and (iii) muscle tissue were prepared and added to tanks holding the fry. Virus transmission occurred from all tissues tested, causing high mortality of the fry. The results underline the potential risk of introduction of VHSV through the trade of fish products.

  2. Induction of feline immunodeficiency virus specific antibodies in cats with an attenuated Salmonella strain expressing the Gag protein.

    NARCIS (Netherlands)

    E.J. Tijhaar (Edwin); C.H.J. Siebelink (Kees); J.A. Karlas (Jos); M.C. Burger; F.R. Mooi (Frits); A.D.M.E. Osterhaus (Albert)

    1997-01-01

    textabstractSalmonella typhimurium aroA strains (SL3261), expressing high levels of the Gag protein of feline immunodeficiency virus (FIV) fused with maltose binding protein (SL3261-MFG), were constructed using an invertible promoter system that allows the stable expression of heterologous antigens

  3. [Construction of recombinant retroviral vector carrying Lab gene of foot-and-mouth disease virus and its expression in bovine kidney (MDBK) cells].

    Science.gov (United States)

    Cong, Guozheng; Zhou, Jianhua; Gao, Shandian; Du, Junzheng; Shao, Junjun; Lin, Tong; Chang, Huiyun; Xie, Qingge

    2008-05-01

    In this study, foot-and-mouth disease virus (FMDV) strain OA/58 RNAs were used as templates for RT-PCR. By the molecular cloning, the Lab gene encoding leader protease called Lpro were cloned in retroviral vector pBPSTR1 to obtain reconstruction retroviral vector termed pBPSTR1-Lab. At different concentrations of puromycin and tetracycline respectively in the cell culture mediums, the growth of bovine kidney cells (MDBK) showed that the optimal puromycin resistant selection concentration was 3 microg/mL and tetracycline regulatory concentration was 1 microg/mL. Pseudotyped retroviral virus particles were produced by transiently co-tansfecting GP2-293 cells with a retroviral vector DNA and VSV-G plasmid. Then MDBK cells were infected by pseudotyped retroviral virus and were continually seeded in the medium at the optimal tetracycline regulatory concentration and puromycin selection concentration for 12 days to obtain puromycin resistant colonies whose genomes contained the Lab gene. After tetracycline removal, synthesis of Lpro induced severe morphological changes in the puromycin resistant MDBK cells. PCR and Western blotting proved that a stable MDBK cell line inducibly expressing the Lab gene under the control of tetracycline was obtained. The experiment might provide a basis for studying that Lpro of FMDV plays an important role in MDBK cell pathogenesis.

  4. Safety and immunogenicity of a rederived, live-attenuated dengue virus vaccine in healthy adults living in Thailand: a randomized trial.

    Science.gov (United States)

    Watanaveeradej, Veerachai; Gibbons, Robert V; Simasathien, Sriluck; Nisalak, Ananda; Jarman, Richard G; Kerdpanich, Angkool; Tournay, Elodie; De La Barrerra, Rafael; Dessy, Francis; Toussaint, Jean-François; Eckels, Kenneth H; Thomas, Stephen J; Innis, Bruce L

    2014-07-01

    Safety and immunogenicity of two formulations of a live-attenuated tetravalent dengue virus (TDEN) vaccine produced using rederived master seeds from a precursor vaccine were tested against a placebo control in a phase II, randomized, double blind trial (NCT00370682). Two doses were administered 6 months apart to 120 healthy, predominantly flavivirus-primed adults (87.5% and 97.5% in the two vaccine groups and 92.5% in the placebo group). Symptoms and signs reported after vaccination were mild to moderate and transient. There were no vaccine-related serious adverse events or dengue cases reported. Asymptomatic, low-level viremia (dengue virus type 2 [DENV-2], DENV-3, or DENV-4) was detected in 5 of 80 vaccine recipients. One placebo recipient developed a subclinical natural DENV-1 infection. All flavivirus-unprimed subjects and at least 97.1% of flavivirus-primed subjects were seropositive to antibodies against all four DENV types 1 and 3 months post-TDEN dose 2. The TDEN vaccine was immunogenic with an acceptable safety profile in flavivirus-primed adults.

  5. A Phase II, Randomized, Safety and Immunogenicity Trial of a Re-Derived, Live-Attenuated Dengue Virus Vaccine in Healthy Children and Adults Living in Puerto Rico

    Science.gov (United States)

    Bauer, Kristen; Esquilin, Ines O.; Cornier, Alberto Santiago; Thomas, Stephen J.; Quintero del Rio, Ana I.; Bertran-Pasarell, Jorge; Morales Ramirez, Javier O.; Diaz, Clemente; Carlo, Simon; Eckels, Kenneth H.; Tournay, Elodie; Toussaint, Jean-Francois; De La Barrera, Rafael; Fernandez, Stefan; Lyons, Arthur; Sun, Wellington; Innis, Bruce L.

    2015-01-01

    This was a double-blind, randomized, controlled, phase II clinical trial, two dose study of re-derived, live-attenuated, tetravalent dengue virus (TDEN) vaccine (two formulations) or placebo in subjects 1–50 years of age. Among the 636 subjects enrolled, 331 (52%) were primed, that is, baseline seropositive to at least one dengue virus (DENV) type. Baseline seropositivity prevalence increased with age (10% [< 2 years], 26% [2–4 years], 60% [5–20 years], and 93% [21–50 years]). Safety profiles of TDEN vaccines were similar to placebo regardless of priming status. No vaccine-related serious adverse events (SAEs) were reported. Among unprimed subjects, immunogenicity (geometric mean antibody titers [GMT] and seropositivity rates) for each DENV increased substantially in both TDEN vaccine groups with at least 74.6% seropositive for four DENV types. The TDEN vaccine candidate showed an acceptable safety and immunogenicity profile in children and adults ranging from 1 to 50 years of age, regardless of priming status. ClinicalTrials.gov: NCT00468858. PMID:26175027

  6. Interleukin 28B gene variation at rs12979860 determines early viral kinetics during treatment in patients carrying genotypes 2 or 3 of hepatitis C virus

    DEFF Research Database (Denmark)

    Lindh, Magnus; Lagging, Martin; Färkkilä, Martti

    2011-01-01

    = 341), we found that rs12979860 strikingly determined the first phase of viral elimination (P sustained virologic response (P = .02), especially among those with high baseline HCV RNA levels (P = .002) or older than 45...... years (P = .01). Patients carrying CC(rs12979860) had higher baseline HCV RNA levels (P sustained virologic response more often than those carrying CT(rs1297986) or TT(rs1297986). The results indicate that IL28B gene testing may identify patients...

  7. Rapid detection and differentiation of wild-type and three attenuated lapinized vaccine strains of classical swine fever virus by reverse transcription polymerase chain reaction.

    Science.gov (United States)

    Pan, Chu-Hsiang; Jong, Ming-Hwa; Huang, Yu-Liang; Huang, Tien-Shine; Chao, Parn-Hwa; Lai, Shiow-Suey

    2008-07-01

    A simple one-step reverse transcription polymerase chain reaction (RT-PCR) method was developed based on T-rich insertions in the viral genome for simultaneous detection and differentiation of wild type and vaccine strains of Classical swine fever virus (CSFV). The CSFV-specific primers were designed to contain the sequences of the T-rich insertion sites that exist uniquely in the 3' nontranslated regions (3' NTR) of the genome of lapinized CSFV vaccine strains. By using a one-step RT-PCR or a nested PCR followed by an agarose gel electrophoresis or a multicapillary electrophoresis, the wild-type and lapinized vaccine strains of CSFV in clinical samples could be detected and accurately distinguished. These assays can be applied to at least 3 attenuated lapinized vaccine strains, lapinized Philippines Coronel (LPC), hog cholera lapinized virus (HCLV), and Chinese strain (C strain). The detection limit of the wild-type virus was 6.3 TCID(50) (50% tissue culture infective dose)/ml for RT-PCR and 0.63 TCID(50)/ml for nested PCR. In previous studies, notable T-rich insertions of 12-13 nucleotides (nt) were found in the 3' NTR of the genome of lapinized vaccine strains of CSFV. However, this study discovered that 2 T-rich insertions, 42 and 36 nt in length, are present in the viral genome of lapinized vaccine strains LPC/PRK (primary rabbit kidney) and LPC/TS (Tam-Sui), respectively. These T-rich insertions of 12, 36, and 42 nt length increases the size of PCR fragments, which are favorable genetic markers for rapid detection of and differentiation between wild-type and different lapinized vaccine strains of CSFV.

  8. Boosted influenza-specific T cell responses after H5N1 pandemic live attenuated influenza virus (pLAIV vaccination

    Directory of Open Access Journals (Sweden)

    Yanchun ePeng

    2015-06-01

    Full Text Available Background: In a phase I clinical trial, a H5N1 pandemic live attenuated influenza virus (pLAIV VN2004 vaccine bearing avian influenza H5N1 HA and NA genes on the A/Ann Arbor cold-adapted vaccine backbone displayed very restricted replication. We evaluated T cell responses to H5N1 pLAIV vaccination and assessed pre-existing T cell responses to to determine whether they were associated with restricted replication of the H5N1 pLAIV. Method: ELISPOT assays were performed using pools of overlapping peptides spanning the entire H5N1 proteome and the hemagglutinin (HA proteins of relevant seasonal H1N1 and H3N2 viruses. We tested stored PBMCs from 21 study subjects who received two doses of the H5N1 pLAIV. The PBMCs were collected 1 day before and 7 days after the first and second pLAIV vaccine doses, respectively. Result: T cell responses to conserved internal proteins M and NP were significantly boosted by vaccination (p=0.036. In addition, H5N1 pLAIV appeared to preferentially stimulate and boost pre-existing seasonal influenza virus HA-specific T cell responses that showed low cross-reactivity with the H5 HA. We confirmed this observation by T cell cloning and identified a novel HA-specific epitope. However, we did not find any evidence that pre-existing T cells prevented pLAIV replication and take. Conclusion: We found that cross-reactive T cell responses could be boosted by pLAIV regardless of the induction of antibody. The impact of the original antigenic sin phenomenon in a subset of volunteers, with preferential expansion of seasonal influenza-specific but not H5N1-specific T cell responses merits further investigation.

  9. Validation of a test for dams carrying foetuses persistently infected with bovine viral-diarrhoea virus based on determination of antibody levels in late pregnancy.

    Science.gov (United States)

    Lindberg, A; Groenendaal, H; Alenius, S; Emanuelson, U

    2001-10-11

    Our objective was to estimate, using a generalised linear mixed-model approach, the sensitivity and specificity of an indirect ELISA when used to identify dams pregnant with persistently bovine viral-diarrhoea virus (BVDV)-infected foetuses. Cows that had been tested for antibodies to BVDV with a positive result during their pregnancy and where the offspring had been tested for both antibody and virus were identified by accessing the Swedish BVD database and the official pedigree records. The resulting data set consisted of 2162 cow-calf pairs in 126 herds, of which 281 included virus-positive calves. The sensitivities and specificities at 12 different decision thresholds (corresponding to optical densities (ODs) between 0.5 and 1.6) were estimated using generalised linear mixed models (binomial error, logit link), in which the gold standard (the BVDV status of the calf) was included as a covariate. In each model, the dependent variable was the dichotomous test result at the decision threshold in question. There was a significant positive interaction between the calf's status and gestational stage in all 12 models--indicating that the sensitivity and specificity at any given decision threshold was improved when the the test was performed later in pregnancy. The test should be applied only when samples have been taken in late gestation--not before the seventh month in pregnancy. If applied during the last months of pregnancy, the point estimate of the sensitivity ranges between 0.94 and 1.0 as the decision threshold is moved from 1.0 and downwards to 0.7. Similarly, the specificity ranges between 0.39 and 0.67 as the decision threshold is moved from 0.8 and upwards to 1.1.

  10. Human glioblastoma cells persistently infected with simian virus 40 carry nondefective episomal viral DNA and acquire the transformed phenotype and numerous chromosomal abnormalities.

    Science.gov (United States)

    Norkin, L C; Steinberg, V I; Kosz-Vnenchak, M

    1985-02-01

    A stable, persistent infection of A172 human glioblastoma cells with simian virus 40 (SV40) was readily established after infection at an input of 450 PFU per cell. Only 11% of the cells were initially susceptible to SV40, as shown by indirect immunofluorescent staining for the SV40 T antigen at 48 h. However, all cells produced T antigen by week 11. In contrast, viral capsid proteins were made in only about 1% of the cells in the established carrier system. Weekly viral yields ranged between 10(4) and 10(6) PFU/ml. Most of the capsid protein-producing cells contained enormous aberrant (lobulated or multiple) nuclei. Persistent viral DNA appeared in an episomal or "free" state exclusively in Southern blots and was indistinguishable from standard SV40 DNA by restriction analysis. Viral autointerference activity was not detected, and yield reduction assays did not indicate defective interfering particle activity, further implying that variant viruses were not a factor in this carrier system. Interferon was also not a factor in the system, as shown by direct challenge with vesicular stomatitis virus. Persistent infection resulted in cellular growth changes (enhanced saturation density and plating efficiency) characteristic of SV40 transformation. Persistent infection also led to an increased frequency of cytogenetic effects. These included sister chromatid exchanges, a variety of chromosomal abnormalities (ring chromosomes, acentric fragments, breaks, and gaps), and an increase in the chromosome number. Nevertheless, the persistently infected cells continued to display a bipolar glial cell-like morphology with extensive process extension and intercellular contacts.

  11. Human Transcriptome Response to Immunization with Live- Attenuated Venezuelan equine encephalitis Virus Vaccine (TC 83): Analysis of Whole Blood

    Science.gov (United States)

    2016-11-21

    Cynomolgus macaques (Macaca 519 fascicularis). Virology J 2007; 4: 82. DOI: 10.1186/1743-422X-4-82. 520 13. Koterski J, Twenhafel N, Porter A, Reed DS...UNCLASSIFIED Page 26 of 39 18. Erwin-Cohen RA, Porter A, Pittman PR, Rossi CA, DaSilva L. (2012). Host responses to 537 live-attenuated...T, Stohlman SA, Bergmann CC, Diamond 551 MS, Virgin HW, Sen GC. Interferon-induced Ifit2/ISG54 protects mice from lethal VSV 552 neuropathogenesis

  12. Simultaneous mutations in multi-viral proteins are required for soybean mosaic virus to gain virulence on soybean genotypes carrying different R genes.

    Directory of Open Access Journals (Sweden)

    R V Chowda-Reddy

    Full Text Available BACKGROUND: Genetic resistance is the most effective and sustainable approach to the control of plant pathogens that are a major constraint to agriculture worldwide. In soybean, three dominant R genes, i.e., Rsv1, Rsv3 and Rsv4, have been identified and deployed against Soybean mosaic virus (SMV with strain-specificities. Molecular identification of virulent determinants of SMV on these resistance genes will provide essential information for the proper utilization of these resistance genes to protect soybean against SMV, and advance knowledge of virus-host interactions in general. METHODOLOGY/PRINCIPAL FINDINGS: To study the gain and loss of SMV virulence on all the three resistance loci, SMV strains G7 and two G2 isolates L and LRB were used as parental viruses. SMV chimeras and mutants were created by partial genome swapping and point mutagenesis and then assessed for virulence on soybean cultivars PI96983 (Rsv1, L-29 (Rsv3, V94-5152 (Rsv4 and Williams 82 (rsv. It was found that P3 played an essential role in virulence determination on all three resistance loci and CI was required for virulence on Rsv1- and Rsv3-genotype soybeans. In addition, essential mutations in HC-Pro were also required for the gain of virulence on Rsv1-genotype soybean. To our best knowledge, this is the first report that CI and P3 are involved in virulence on Rsv1- and Rsv3-mediated resistance, respectively. CONCLUSIONS/SIGNIFICANCE: Multiple viral proteins, i.e., HC-Pro, P3 and CI, are involved in virulence on the three resistance loci and simultaneous mutations at essential positions of different viral proteins are required for an avirulent SMV strain to gain virulence on all three resistance loci. The likelihood of such mutations occurring naturally and concurrently on multiple viral proteins is low. Thus, incorporation of all three resistance genes in a soybean cultivar through gene pyramiding may provide durable resistance to SMV.

  13. Vaccination of pigs against Aujeszky's disease by the intradermal route using live attenuated and inactivated virus vaccines.

    Science.gov (United States)

    Vannier, P; Cariolet, R

    1989-09-01

    A study was undertaken of the protection induced by inactivated and live Aujeszky's disease virus vaccines. The vaccines were administered using a special device which, without the use of a needle, delivered the preparation intradermally. The trials were performed on 88 pigs which were vaccinated at the beginning of the fattening period both in experimental conditions and in pig herds. All the pigs were challenged at the end of the fattening period in isolation units. The results obtained were compared with those obtained using the same vaccines injected intramuscularly. It was shown that vaccination via the intradermal route induced good protection in the vaccinated animals and was similar to that conferred by live virus vaccine injected intramuscularly. The results, with the inactivated virus vaccine, were not so good when it was injected via the intradermal route. Studies with intradermal vaccination showed no local lesion or very small nodules strictly localized to the dermis. The results also confirmed that the effects of challenge exposure depended on the health status of animals prior to infection and show the necessity to use a synthetic value (delta G) to interpret the data and mainly to compare the results objectively. In fattening pigs this vaccination procedure is attractive because (i) less animal constraint is needed than would be for intramuscular injections, (ii) injection can be checked by the presence of a visible papula at the site of inoculation and, (iii) pigs can be vaccinated in the ham while they are feeding. Injection without a needle also contributes to avoiding bacterial contamination under practical farm conditions of vaccination.

  14. Immunogenicity of Attenuated Vaccinia Virus Guang 9 Strain%痘苗病毒弱毒株广9株的免疫原性分析

    Institute of Scientific and Technical Information of China (English)

    朱蓉; 黄维金; 王佑春; 俞永新

    2011-01-01

    目的 分析痘苗病毒弱毒株广9株(Vaccinia virus Guang 9 strain,VG9)对BALB/c小鼠的免疫原性.方法 用鸡胚成纤维细胞培养痘苗病毒VG9株和天坛株(Vaccinia virus Tian Tan strain,VTT),离心纯化病毒,经小鼠背部皮内免疫后,每周采血,共4次,采用ELISA法检测小鼠血清中抗痘苗病毒特异性抗体效价;中和试验检测免疫后3周和4周小鼠血清中和抗体效价.结果 两株痘苗病毒免疫后1周,小鼠血清中即产生抗痘苗病毒特异性抗体,效价均达1∶4050;至第3周,抗体效价上升至1∶12 150;第4周时,VG9株抗体效价维持在1∶12 150,而VTT株效价可达1:36 450.两株病毒诱导的中和抗体水平均在免疫后3周达峰值,且具有交叉中和作用,均对VTT株中和效果更好,VG9株诱导产生中和抗体的能力较VTT株略低.结论 痘苗病毒VG9株与VTT株一样,具有良好的免疫原性,皮内免疫均能刺激小鼠产生良好的抗痘菌病毒特异性抗体和中和抗体.%Objective To analyze the immunogenicity of attenuated vaccinia virus Guang 9 (VG9) strain. Methods VG9 and Vaccinia virus Tian Tan (VTT) strains were cultured in chick embryo fibroblasts (CEFs), purified by centrifugation and inoculated I.d. Into BALB /c mice. Serum samples were collected once a week for 4 times, and determined for specific antibody liter against vaccinia virus by ELJSA. The neutralizing antibody liters in sera 3 and 4 weeks after immunization were determined by neutralization test. Results Specific antibody liters against vaccinia virus in sera of mice were 1 : 4 050 one week after immunization with both the strains and increased to 1 : 12 150 on week 3. However, the antibody titers against VG9 and VTT strains on week 4 after immunization were 1 : 12 150 and 1 : 36 450 respectively. Both the neutralizing antibody levels induced by the two strains reached peak values 3 weeks after immunization, and cross neutralization was observed. The neutralizing effect on

  15. Depo-provera treatment does not abrogate protection from intravenous SIV challenge in female macaques immunized with an attenuated AIDS virus.

    Directory of Open Access Journals (Sweden)

    Meritxell Genescà

    Full Text Available BACKGROUND: In a previous study, progesterone treatment of female monkeys immunized with live, attenuated SHIV89.6 abrogated the generally consistent protection from vaginal simian immunodeficiency virus (SIV challenge. The mechanisms responsible for the loss of protection remain to be defined. The objective of the present study was to determine whether Depo-Provera administration alters protection from intravenous SIV challenge in SHIV-immunized female macaques. METHODS AND FINDINGS: Two groups of female macaques were immunized with attenuated SHIV89.6 and then challenged intravenously with SIVmac239. Four weeks before challenge, one animal group was treated with Depo-Provera, a commonly used injectable contraceptive progestin. As expected, SHIV-immunized monkeys had significantly lower peak and set-point plasma viral RNA levels compared to naïve controls, but in contrast to previously published findings with vaginal SIV challenge, the Depo-Provera SHIV-immunized animals controlled SIV replication to a similar, or even slightly greater, degree than did the untreated SHIV-immunized animals. Control of viral replication from week 4 to week 20 after challenge was more consistent in the progesterone-treated, SHIV-immunized animals than in untreated, SHIV-immunized animals. Although levels of interferon-gamma production were similar, the SIV-specific CD8(+ T cells of progesterone-treated animals expressed more functions than the anti-viral CD8(+ T cells from untreated animals. CONCLUSIONS: Depo-Provera did not diminish the control of viral replication after intravenous SIV challenge in female macaques immunized with a live-attenuated lentivirus. This result contrasts with the previously reported effect of Depo-Provera(R on protection from vaginal SIV challenge and strongly implies that the decreased protection from vaginal challenge is due to effects of progesterone on the genital tract rather than to systemic effects. Further, these results

  16. Hepatitis A virus-encoded miRNAs attenuate the accumulation of viral genomic RNAs in infected cells.

    Science.gov (United States)

    Shi, Jiandong; Sun, Jing; Wu, Meini; Hu, Ningzhu; Hu, Yunzhang

    2016-06-01

    The establishment of persistent infection with hepatitis A virus (HAV) is the common result of most HAV/cell culture systems. Previous observations show that the synthesis of viral RNAs is reduced during infection. However, the underlying mechanism is poorly understood. We characterized three HAV-encoded miRNAs in our previous study. In this study, we aim to investigate the impact of these miRNAs on the accumulation of viral RNAs. The results indicated that the synthesis of viral genomic RNAs was dramatically reduced (more than 75 % reduction, P < 0.05) when transfected with one or two viral miRNA mimics. Conversely, they were significantly increased (more than 3.3-fold addition, P < 0.05) when transfected with one or two viral miRNA inhibitors. The luciferase reporter assay of miRNA targets showed that viral miRNAs were fully complementary to specific sites of the viral plus or minus strand RNA and strongly inhibited their expressions. Further data showed that the relative abundance of viral genomic RNA fragments that contain miRNA targets was also dramatically reduced (more than 80 % reduction, P < 0.05) when viral miRNAs were overexpressed with miRNA mimics. In contrast, they were significantly increased (approximately 2-fold addition, P < 0.05) when viral miRNAs were inhibited with miRNA inhibitors. In conclusion, these data suggest a possible mechanism for the reduction of viral RNA synthesis during HAV infection. Thus, we propose that it is likely that RNA virus-derived miRNA could serve as a self-mediated feedback regulator during infection.

  17. Studies on the induction of Epstein-Barr virus (EBV) DNA polymerase (POL) and deoxyribonuclease (DNase) by the combined action of 12-O-tetradecanoyl-phorbol-13-acetate (TPA) and N-butyrate (SB in EBV-carrying cells

    Energy Technology Data Exchange (ETDEWEB)

    Nutter, L.M.; Tan, R.S.; Grill, S.; Li, J.S.; Cheng, Y.C.

    1986-03-05

    TPA and SB were found to induce EBV early antigen in EBV-carrying Raji cells, a Burkitt's Lymphoma-derived human cell line. The mode of interaction of these agents was unclear. They have examined the induction of EBV-POL and DNase activities by TPA and SB. It was found that neither agent alone could induce EBV-POL and DNase activities, even though the virus DNA could be induced by either compound alone. Induction of virus enzymes could only occur when cells were exposed to both compounds. A 2h exposure to TPA followed by 46h to SB resulted in levels of induction of EBV-POL and DNase activities comparable to those induced with simultaneous exposure to both agents for 48h. No induction of the enzymes will occur if the sequence of exposure to these agents is reversed. Phospholipase C, which increases intracellular diacylglycerol (and subsequently the activation of Protein Kinase C), and 5-Aza-deoxycytidine, a DNA hypomethylating agent, were able to partially substitute for TPA and SB, respectively. These results suggest that the mechanism of induction of EBV enzyme activities by TPA and SB could involve both Protein Kinase C activation and DNA hypomethylation. Furthermore, the synthesis of EBV DNA is not sufficient for induction of these virus enzyme activities.

  18. Expression Analysis of Hairpin RNA Carrying Sugarcane mosaic virus (SCMV) Derived Sequences and Transgenic Resistance Development in a Model Rice Plant

    Science.gov (United States)

    Akbar, Sehrish; Wang, Ming-Bo; Liu, Qing

    2017-01-01

    Developing transgenic resistance in monocotyledonous crops against pathogens remains a challenging area of research. Sugarcane mosaic virus (SCMV) is a serious pathogen of many monocotyledonous crops including sugarcane. The objective of present study was to analyze transgenic expression of hairpin RNA (hpRNA), targeting simultaneously CP (Coat Protein) and Hc-Pro (helper component-proteinase) genes of SCMV, in a model rice plant. Conserved nucleotide sequences, exclusive for DAG (Aspartic acid-Alanine-Glycine) and KITC (Lycine-Isoleucine-Threonine-Cysteine) motifs, derived from SCMV CP and Hc-Pro genes, respectively, were fused together and assembled into the hpRNA cassette under maize ubiquitin promoter to form Ubi-hpCP:Hc-Pro construct. The same CP:Hc-Pro sequence was fused with the β-glucuronidase gene (GUS) at the 3′ end under CaMV 35S promoter to develop 35S-GUS:CP:Hc-Pro served as a target reporter gene construct. When delivered into rice callus tissues by particle bombardment, the Ubi-hpCP:Hc-Pro construct induced strong silencing of 35S-GUS:CP:Hc-Pro. Transgenic rice plants, containing Ubi-hpCP:Hc-Pro construct, expressed high level of 21–24 nt small interfering RNAs, which induced specific suppression against GUS:CP:Hc-Pro delivered by particle bombardment and conferred strong resistance to mechanically inoculated SCMV. It is concluded that fusion hpRNA approach is an affordable method for developing resistance against SCMV in model rice plant and it could confer SCMV resistance when transformed into sugarcane. PMID:28255554

  19. Anti-viral and anti-tumor effects induced by an attenuated Marek's disease virus in CD4- or CD8-deficient chickens.

    Science.gov (United States)

    Morimura, T; Cho K-O; Kudo, Y; Hiramoto, Y; Ohashi, K; Hattori, M; Sugimoto, C; Onuma, M

    1999-01-01

    By vaccination with an attenuated Marek's disease virus (MDV), strain CVI988, chickens are protected from the development of T cell lymphoma caused by an oncogenic MDV. To clarify the role of T lymphocyte subsets in the protection mechanisms of this vaccine, vaccinated chickens were depleted of T cell subsets by neonatal thymectomy and injections of monoclonal antibodies specific to chicken CD4 and CD8 molecules, and then challenged with an oncogenic MDV, strain Md5. The MDV titers rescued from CD8(+) T cells, which are the main targets for latent infection and subsequent transformation by MDV, was much higher in the CD8-deficient vaccinated chickens than in untreated vaccinated chickens at the early stage of the latent phase. However, the neonatal vaccination prevented lymphoma formation by strain Md5 even in either CD4(+) or CD8(+) T cell-depleted chickens. These results suggest that specific CD8(+) T cell responses induced by the MD vaccine play a crucial role in the prevention of MDV infection during the latent phase, but may not be essential for the prevention of lymphoma formation by an oncogenic MDV.

  20. Construction and expression of attenuated salmonella typhimurium carrying human adiponectin gene eukaryotic expression vector%重组人脂联素基因在减毒沙门氏菌中的表达

    Institute of Scientific and Technical Information of China (English)

    周静; 周洲; 吴莹; 向廷秀; 姜政; 王丕龙

    2009-01-01

    目的:构建携带人脂联素(AdipoQ)基因真核表达载体并在减毒沙门氏菌中表达,为AdipoQ对非酒精性脂肪性肝病(NAFLD)的基因治疗提供依据.方法:从人脂肪组织中提取总RNA,通过实时荧光定量PCR(rRT-PCR)方法获得Adi-poQ基因并将其克隆到真核表达载体pEGFP-NI上,构建pEG-FP-N1-AdipoQ重组载体.重组质粒经鉴定后再电转入减毒沙门氏菌SL7207中表达.结果:克隆的人AdipoQ基因744 bp测序结果显示:1个碱基发生突变,654位:A→T,突变率为0.1%,氨基酸Glu→Asp.经SDS-PAGE,Western Blot检测融合蛋白Mr约为55×10~3(绿色荧光蛋白Mr约为27×10~3),能够被AdipoQ抗体识别.结论:成功构建携带AdipoQ基因真核表达载体的减毒沙门氏菌株,AdipoQ基因能够在减毒沙门氏菌中表达并与绿色荧光蛋白融合.为进一步研究其在NAFLD中的作用机制奠定了基础.%AIM: To construct and express an attenuated Salmonella typhimurium strain contraining human adiponectin gene eukaryotic expression vector, in order to lay the foundation for the genetic therapy of nonalcoholic fatty liver disease in future. METHODS: Total mRNA was extracted from human fat tissue and the adiponectin cDNA was obtained by RT-PCR, and then cloned into eukaryotic expression vector pEGFP-N1. The recombinant vector was identified, and transformed into attenuated Salmonella typhimurium strain SL7207, and the recombinant strain SL7207/pEGFP-NI-AdipoQ was screened by green fluorescent microscope and Western Blot. RESULTS: Enzyme digestion analysis and sequencing showed that the target genes was found to be 744 bp, and had been inserted into eukaryotic expression vector, but as compared with gene reported by GenBank, 0. 1% of the gene mutation and O. 4% of amino acid residues change, respectively: 654 bp: A→T, amino acids: Glu→Asp. SDS-PAGE demonstrated that pEGFP-N1-AdipoQ was expressed in SL7207 strain, and the relatived molecular mass of the GFP-AdipoQ fusion protein

  1. Some human immunodeficiency virus type 1 Vpu proteins are able to antagonize macaque BST-2 in vitro and in vivo: Vpu-negative simian-human immunodeficiency viruses are attenuated in vivo.

    Science.gov (United States)

    Shingai, Masashi; Yoshida, Takeshi; Martin, Malcolm A; Strebel, Klaus

    2011-10-01

    Human immunodeficiency virus type 1 (HIV-1) Vpu enhances the release of viral particles from infected cells by targeting BST-2/tetherin, a cellular protein inhibiting virus release. The widely used HIV-1(NL4-3) Vpu functionally inactivates human BST-2 but not murine or monkey BST-2, leading to the notion that Vpu antagonism is species specific. Here we investigated the properties of the CXCR4-tropic simian-human immunodeficiency virus DH12 (SHIV(DH12)) and the CCR5-tropic SHIV(AD8), each of which carries vpu genes derived from different primary HIV-1 isolates. We found that virion release from infected rhesus peripheral blood mononuclear cells was enhanced to various degrees by the Vpu present in both SHIVs. Transfer of the SHIV(DH12) Vpu transmembrane domain to the HIV-1(NL4-3) Vpu conferred antagonizing activity against macaque BST-2. Inactivation of the SHIV(DH12) and SHIV(AD8) vpu genes impaired virus replication in 6 of 8 inoculated rhesus macaques, resulting in lower plasma viral RNA loads, slower losses of CD4(+) T cells, and delayed disease progression. The expanded host range of the SHIV(DH12) Vpu was not due to adaptation during passage in macaques but was an intrinsic property of the parental HIV-1(DH12) Vpu protein. These results demonstrate that the species-specific inhibition of BST-2 by HIV-1(NL4-3) Vpu is not characteristic of all HIV-1 Vpu proteins; some HIV-1 isolates encode a Vpu with a broader host range.

  2. Attenuation of pathogenic immune responses during infection with human and simian immunodeficiency virus (HIV/SIV by the tetracycline derivative minocycline.

    Directory of Open Access Journals (Sweden)

    Julia L Drewes

    Full Text Available HIV immune pathogenesis is postulated to involve two major mechanisms: 1 chronic innate immune responses that drive T cell activation and apoptosis and 2 induction of immune regulators that suppress T cell function and proliferation. Both arms are elevated chronically in lymphoid tissues of non-natural hosts, which ultimately develop AIDS. However, these mechanisms are not elevated chronically in natural hosts of SIV infection that avert immune pathogenesis despite similarly high viral loads. In this study we investigated whether minocycline could modulate these pathogenic antiviral responses in non-natural hosts of HIV and SIV. We found that minocycline attenuated in vitro induction of type I interferon (IFN and the IFN-stimulated genes indoleamine 2,3-dioxygenase (IDO1 and TNF-related apoptosis inducing ligand (TRAIL in human plasmacytoid dendritic cells and PBMCs exposed to aldrithiol-2 inactivated HIV or infectious influenza virus. Activation-induced TRAIL and expression of cytotoxic T-lymphocyte antigen 4 (CTLA-4 in isolated CD4+ T cells were also reduced by minocycline. Translation of these in vitro findings to in vivo effects, however, were mixed as minocycline significantly reduced markers of activation and activation-induced cell death (CD25, Fas, caspase-3 but did not affect expression of IFNβ or the IFN-stimulated genes IDO1, FasL, or Mx in the spleens of chronically SIV-infected pigtailed macaques. TRAIL expression, reflecting the mixed effects of minocycline on activation and type I IFN stimuli, was reduced by half, but this change was not significant. These results show that minocycline administered after infection may protect against aspects of activation-induced cell death during HIV/SIV immune disease, but that in vitro effects of minocycline on type I IFN responses are not recapitulated in a rapid progressor model in vivo.

  3. Live attenuated influenza vaccine--a review.

    Science.gov (United States)

    Gasparini, R; Amicizia, D; Lai, P L; Panatto, D

    2011-09-01

    Owing to the variability of influenza viruses, vaccine composition needs to be up-dated annually. As many variables can influence their efficacy, vaccines are still considered "sub-optimal". Many studies have been carried out in recent years to improve vaccines. In particular, researchers and vaccine-producing corporations have focused on developing a live vaccine. Among the candidate vaccines, the strain developed by Maassab has recently been licensed in the USA and Europe, after extensive investigation. This vaccine is safe and well tolerated, and has shown very good genetic stability. Although vaccine recipients are able to spread the virus, transmission to close contacts is practically non-existent. Studies on cold-adapted attenuated influenza vaccines have demonstrated that such vaccines are effective, and sometimes more effective than inactivated influenza vaccines. Cold-adapted attenuated influenza vaccines therefore appear to be an important weapon against influenza. However, a more widespread use of these vaccines is to be recommended, especially in children, as the more acceptable way of administration can favour parental compliance.

  4. Immunization of aged pigs with attenuated pseudorabies virus vaccine combined with CpG oligodeoxynucleotide restores defective Th1 immune responses.

    Directory of Open Access Journals (Sweden)

    Feiping Ming

    Full Text Available BACKGROUND AND AIMS: Attempts to immunize aged subjects often result in the failure to elicit a protective immune response. Murine model studies have shown that oligonucleotides containing CpG motifs (CpG ODN can stimulate immune system in aged mice as effectively as in young mice. Since many physiological and pathophysiological data of pigs can be transferred to humans, research in pigs is important to confirm murine data. Here we investigated whether immunization of aged pig model with attenuated pseudorabies virus vaccine (PRV vaccine formulated with CpG ODN could promote a successful development of immune responses that were comparable to those induced in young pigs in a similar manner. METHODOLOGY: Young and aged pigs were immunized IM with PRV vaccine alone, or in combination with CpG ODN respectively. At days 3, 7, 14 post immunization sera were assayed by ELISA for IgG titres, at day 7 for IgG1 and IgG2 subtypes titres. All blood samples collected in evacuated test tubes with K-EDTA at day 7 were analyzed for flow cytometer assay. Blood samples at day 7 collected in evacuated test tubes with heparin were analysed for antigen-specific cytokines production and peripheral blood mononuclear cells (PBMCs proliferative responses. RESULTS: CpG ODN could enhance Th1 responses (PRV-specific IgG2/IgG1 ratio, proliferative responses, Th1 cytokines production when used as an adjuvant for the vaccination of aged pigs, which were correlated with enhanced CD4+ T cells percentage, decreased CD4+CD8+CD45RO+ T cells percentage and improved PRV-specific CD4+ T cells activation. CONCLUSIONS: Our results demonstrate a utility for CpG ODN, as a safe vaccine adjuvant for promoting effective systemic immune responses in aged pig model. This agent could have important clinical uses in overcoming some of age-associated depressions in immune function that occur in response to vaccination.

  5. H7N9 live attenuated influenza vaccine is highly immunogenic, prevents virus replication, and protects against severe bronchopneumonia in ferrets

    NARCIS (Netherlands)

    Jonge, de J.; Isakova-Sivak, Irina; Dijken, van Harry; Spijkers, Sanne; Mouthaan, Justin; Klaassen-de Jong, Rineke; Smolonogina, Tatiana; Roholl, Paul; Rudenko, Larisa

    2016-01-01

    Avian influenza viruses continue to cross the species barrier, and if such viruses become transmissible among humans, it would pose a great threat to public health. Since its emergence in China in 2013, H7N9 has caused considerable morbidity and mortality. In the absence of a universal influenza

  6. 人单纯疱疹病毒BDNF转基因重组体的构建表达及活性检测%Constrution of Human Single Herpes Virus Carried BDNF Gene Vector and Its Bioactivity Evaluation

    Institute of Scientific and Technical Information of China (English)

    王盛兰; 但齐琴; 荣荣; 王廷华; 张云辉

    2012-01-01

    目的 构建人单纯疱疹病毒(HSV)脑源性神经营养因子(BDNF)转基因重组体(HSV-BDNF),转染大鼠皮质神经元后并检测其表达及生物活性.方法 用RT-PCR方法扩增人BDNF基因,克隆并构建HSV-BDNF转基因重组体.构建成功后将其转染培养大鼠皮质神经元,观察其对皮质神经元存活的影响;用ELISA、免疫组化检测皮质神经元中BDNF的表达水平.结果 成功构建了HSV-BDNF转基因重组体,皮质神经元转染HSV-BDNF后BDNF表达水平明显上调(P<0.05),且明显促进皮质神经元生长(P<0.05).结论 成功构建了HSV-BDNF,能有效转染大鼠皮质神经元并促进BDNF高表达,且具有生物活性.%Objective To construct the recombinant vector of human single herpes virus (HSV) carried brain derived neurotrophic factor (BDNF) gene. Methods BDNF gene was acquired from rat brain tissue by RT-PCR, then was cloned into plasmid, and enveloped by HSV. The recombinant was used to transfer cultured cortical neurons. The number and neurite length of neurons were quantified. The BDNF level and subcellular localization were detected by ELISA and immunohistochemistry. Results HSV carried BDNF gene recombinant has been successfully constructed. The recombinant showed the bioactivity on the growth of cortical neurons. BDNF level was increased significantly in BDNF transferred group. Conclusion HSV carried BDNF gene recombinant. With the bioactivity, has been successfully constructed. This could provide the vector for the treatment of BDNF under disease condition base on transferring gene technique.

  7. Analysis of Sister Carrie

    Institute of Scientific and Technical Information of China (English)

    孙淑珍

    2004-01-01

    Chapter Ⅰ Introduction  Sitting in the rocking chair,Carrie dreams her future.This is the deep impression the novel"Sister Carrie"gives us,which is written by Theodore Dreiser(1871-1945),the great American realism writer.  ……

  8. Measles virus selectively blind to signaling lymphocytic activation molecule (SLAM; CD150) is attenuated and induces strong adaptive immune responses in rhesus monkeys.

    Science.gov (United States)

    Leonard, Vincent H J; Hodge, Gregory; Reyes-Del Valle, Jorge; McChesney, Michael B; Cattaneo, Roberto

    2010-04-01

    The signaling lymphocytic activation molecule (SLAM; CD150) is the immune cell receptor for measles virus (MV). To assess the importance of the SLAM-MV interactions for virus spread and pathogenesis, we generated a wild-type IC-B MV selectively unable to recognize human SLAM (SLAM-blind). This virus differs from the fully virulent wild-type IC-B strain by a single arginine-to-alanine substitution at amino acid 533 of the attachment protein hemagglutinin and infects cells through SLAM about 40 times less efficiently than the isogenic wild-type strain. Ex vivo, this virus infects primary lymphocytes at low levels regardless of SLAM expression. When a group of six rhesus monkeys (Macaca mulatta) was inoculated intranasally with the SLAM-blind virus, no clinical symptoms were documented. Only one monkey had low-level viremia early after infection, whereas all the hosts in the control group had high viremia levels. Despite minimal, if any, viremia, all six hosts generated neutralizing antibody titers close to those of the control monkeys while MV-directed cellular immunity reached levels at least as high as in wild-type-infected monkeys. These findings prove formally that efficient SLAM recognition is necessary for MV virulence and pathogenesis. They also suggest that the selectively SLAM-blind wild-type MV can be developed into a vaccine vector.

  9. Stability and efficacy of the 3'-UTR A4G-G5A variant of viral hemorrhagic septicemia virus (VHSV) as a live attenuated immersion VHSV vaccine in olive flounder (Paralichthys olivaceus).

    Science.gov (United States)

    Kim, Sung-Hyun; Kim, Meesun; Choi, Go-Eun; Lee, Jeong Ho; Kang, Jung-Ha; Evensen, Øystein; Lee, Woo-Jai

    2016-02-17

    Viral hemorrhagic septicemia virus (VHSV) is the causative agent of viral hemorrhagic septicemia in fish, a disease that affects a number of teleost fish species including olive flounder (Paralichthys olivaceus). In this study, we assessed the safety and efficacy of two recombinant attenuated VHSV strains, termed A4G-G5A and ΔNV, with the purpose to select the most suitable vaccine strain. The virus strains were passaged in two commercially available cell lines, EPC and RTG-2, and the strains were also tested for residual virulence in zebrafish (Danio rerio). The A4G-G5A strain showed an attenuated growth profile in both the EPC and RTG-2 cell lines compared to wild-type (WT) VHSV (JF-09, genotype IVa), whereas the growth profile of ΔNV was comparable to the WT strains in RTG-2 cells in contrast to EPC cells. Moreover, ΔNV had higher residual virulence compared to A4G-G5A and was highly pathogenic to zebrafish. The A4G-G5A strain was chosen as vaccine candidate and tested for efficacy in in vivo fish studies in the target species, olive flounder, using an immersion vaccine scheme. Groups of fish were immunized with 10(2.5), 10(3.5), 10(4.5), and 10(5.5) TCID50/ml of A4G-G5A giving 5-13.3 cumulative percent mortality (CPM) post immunization. Immunization was followed by a challenge experiment using VHSV-WT. The relative percent survival (RPS) in immunized groups ranged from 81.6% to 100%, correlating with vaccination dose. This study demonstrates that while strain A4G-G5A has retained some residual virulence it confers high level of protection in immunized olive flounder.

  10. Major histocompatibility complex-linked immune response of young chickens vaccinated with an attenuated live infectious bursal disease virus vaccine followed by an infection

    DEFF Research Database (Denmark)

    Juul-Madsen, Helle; Nielsen, O.L.; Krogh-Maibom, T.;

    2002-01-01

    further contains the BW1 haplotype isolated from a Red jungle Fowl. Line 131 further contains the B131 haplotype isolated from a meat-type chicken, Finally, Line 21 further contains the international B21 haplotype. The chickens were vaccinated with live attenuated commercial IBDV vaccine at 3 wk of age...... Jungle Fowl genes, was clearly differentiated from the other two investigated lines. These results suggest an MHC II restricted T-cell dependent secondary antibody response against IBDV....

  11. Sister Carrie in China

    Institute of Scientific and Technical Information of China (English)

    殷希

    2015-01-01

    Sister Carrie has received many Chinese scholar's attention, and it has quantity relevance researches. Therefore, it is valuable to study why it is popular in China and it's education meaning for Chinese people. In addition, to analysis the domestic re-searches and find it's exist problems can help us make a new breakthrough from the study.

  12. 鸭瘟强毒株和疫苗株对雏鸭IFN-γ基因表达的影响%Dynamics of IFN-γ mRNA Expression in Ducks Induced by Duck Plague Virus and Attenuated Virus

    Institute of Scientific and Technical Information of China (English)

    谢秀兰; 杨发龙; 李阳友; 马小明; 岳华

    2011-01-01

    本试验旨在探讨不同毒力的鸭瘟病毒(DPV)感染对雏鸭INF-γ mRNA表达水平的影响,为DPV的感染与免疫机制提供理论依据.应用实时荧光定量PCR技术,对接种了鸭瘟强毒株和疫苗株的雏鸭肝脏及外周血淋巴细胞(PBL)中IFN-γmRNA的表达水平及鸭瘟病毒(DPV)的荷载量进行动态定量监测.结果表明:①感染鸭瘟强毒后,IFN-γ mRNA在肝脏中的表达没有明显规律,PBL中IFN-γ mRNA表达水平很高,在此期间(1~12 h),病毒DNA量很少.IFN-γ mRNA表达量在6h后大幅下降,直到144 h都非常低,而病毒的载量逐渐增大,至144 h时达到峰值.②接种弱毒疫苗后,肝脏中IFN-γ mRNA表达水平较高且稳定,至12 h达到顶峰,约比对照高出8倍.PBL中IFN-γ mRNA表达量较低且不稳定.弱毒DNA荷载量稳定上升,但载量约比强毒低两个数量级.病毒DNA在PBL检测不到.IFN-γ在抵抗鸭瘟强毒中发挥了重要作用;IFN-γ在肝脏中高水平的表达可能是鸭瘟疫苗的免疫机制之一.%To understand the mechanisms of DPV infection and immunity,the IFN-γ mRNA expression was investigated after infection with virulent and attenuated duck plague virus. The mRNA levels of IFN-γ in liver and PBL were evaluated dynamically after inoculation with virulent and attenuated DPV respectively by real-time PCR. The virus loads were also assessed. Results:①After infection by virulent DPV, IFN-γ mRNA levels in liver didn't show regulatory changes while high level of IFN-γ mRNA levels in PBL and few virus DNA could be detected in the early stage of infection (1-12 h). IFN-γ mRNA expression decreased dramatically after 6 h post infection and persisted in a very low level until death (144 h). Virus load increased gradually and reached peak at 144 h. ②After vaccination with attenuated DPV strain, there were persist and high levels of IFN-γ mRNA expression in liver, reached peak at 12 h (8 times higher than control). While the level-in PBL was

  13. NLRX1 protein attenuates inflammatory responses to virus infection by interfering with the RIG-I-MAVS signaling pathway and TRAF6 ubiquitin ligase

    OpenAIRE

    Allen, Irving C.; Moore, Chris B.; Schneider, Monika; Lei, Yu; Davis, Beckley K; Scull, Margaret A.; Gris, Denis; Roney, Kelly E.; Zimmermann, Albert G.; Bowzard, John B; Ranjan, Priya; MONROE, KATHRYN M.; Pickles, Raymond J.; Sambhara, Suryaprakash; Ting, Jenny P. Y.

    2011-01-01

    The nucleotide-binding domain and leucine-rich repeat containing (NLR) proteins regulate innate immunity. Although the positive regulatory impact of NLRs is clear, their inhibitory roles are not well defined. We showed Nlrx1−/− mice exhibited increased expression of antiviral signaling molecules IFN-β, STAT2, OAS1 and IL-6 after influenza virus infection. Consistent with increased inflammation, Nlrx1−/− mice exhibited marked morbidity and histopathology. Infection of these mice with an influe...

  14. Infection of nonhost species dendritic cells in vitro with an attenuated myxoma virus induces gene expression that predicts its efficacy as a vaccine vector.

    Science.gov (United States)

    Top, S; Foulon, E; Pignolet, B; Deplanche, M; Caubet, C; Tasca, C; Bertagnoli, S; Meyer, G; Foucras, G

    2011-12-01

    Recombinant myxoma virus (MYXV) can be produced without a loss of infectivity, and its highly specific host range makes it an ideal vaccine vector candidate, although careful examination of its interaction with the immune system is necessary. Similar to rabbit bone marrow-derived dendritic cells (BM-DCs), ovine dendritic cells can be infected by SG33, a MYXV vaccine strain, and support recombinant antigen expression. The frequency of infected cells in the nonhost was lower and the virus cycle was abortive in these cell types. Among BM-DC subpopulations, Langerhans cell-like DCs were preferentially infected at low multiplicities of infection. Interestingly, ovine BM-DCs remained susceptible to MYXV after maturation, although apoptosis occurred shortly after infection as a function of the virus titer. When gene expression was assessed in infected BM-DC cultures, type I interferon (IFN)-related and inflammatory genes were strongly upregulated. DC gene expression profiles were compared with the profiles produced by other poxviruses in interaction with DCs, but very few commonalities were found, although genes that were previously shown to predict vaccine efficacy were present. Collectively, these data support the idea that MYXV permits efficient priming of adaptive immune responses and should be considered a promising vaccine vector along with other poxviruses.

  15. Proteomic Analysis of Pathogenic and Attenuated Alcelaphine Herpesvirus 1▿

    Science.gov (United States)

    Dry, Inga; Haig, David M.; Inglis, Neil F.; Imrie, Lisa; Stewart, James P.; Russell, George C.

    2008-01-01

    The gammaherpesvirus alcelaphine herpesvirus 1 (AlHV-1) causes malignant catarrhal fever in susceptible ungulates but infects its natural host, wildebeest, without obvious clinical signs. In tissue culture, AlHV-1 is initially predominantly cell associated and virulent but on extended culture becomes cell-free and attenuated. We wanted to determine what changes in protein composition had taken place during the transition from virulent to attenuated virus in culture. Purified virus preparations were fractionated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and proteins were analyzed by liquid chromatography-electrospray ionization-tandem mass spectrometry. Peptides were identified in serial gel slices by using MASCOT software to interrogate virus-specific and nonredundant sequence databases. Twenty-three AlHV-1-encoded proteins and six cellular proteins were identified in the attenuated and virulent viruses. Two polypeptides were detected in only the virulent virus preparations, while one other protein was found in only the attenuated virus. Two of these virus-specific proteins were identified by a single peptide, suggesting that these may be low-abundance virion proteins rather than markers of attenuation or pathogenesis. The results suggest that attenuation of AlHV-1 is not the result of gross changes in the composition of the virus particle but probably due to altered viral gene expression in the infected cell. PMID:18353942

  16. Deletion of African swine fever virus Georgia 2007 virulence-associated gene 9GL (B119L) leads to virus attenuation in swine at low doses while inducing an effective protection against homologous challenge

    Science.gov (United States)

    African swine fever virus (ASFV) is the etiological agent of a contagious and often lethal viral disease of domestic pigs that has significant economic consequences for swine breeding. The control of African Swine Fever (ASF) has been hampered by the unavailability of vaccines. Experimental vaccines...

  17. African swine fever virus Georgia isolate harboring deletions of MGF360 and MGF505 genes is attenuated in swine and confers protection against challenge with the virulent parental virus

    Science.gov (United States)

    African swine fever virus (ASFV) is the etiological agent of a contagious and often lethal disease of domestic pigs that has significant economic consequences for the swine industry. The control of African Swine Fever (ASF) has been hampered by the unavailability of vaccines. Experimental vaccines h...

  18. African Swine Fever Virus Georgia isolate harboring deletions of 9GL and MGF360/505 genes in highly attenuated in swine but does not confer protection against parental virus challenge

    Science.gov (United States)

    African swine fever virus (ASFV) produces a contagious disease of domestic pigs that results in severe economic consequences to the swine industry. Control of the disease has been hampered by the unavailability of vaccines. We recently reported the development of two experimental vaccine strains (...

  19. Characterization of two recent Japanese field isolates of canine distemper virus and examination of the avirulent strain utility as an attenuated vaccine.

    Science.gov (United States)

    Takenaka, Akiko; Yoneda, Misako; Seki, Takahiro; Uema, Masashi; Kooriyama, Takanori; Nishi, Toshiya; Fujita, Kentaro; Miura, Ryuichi; Tsukiyama-Kohara, Kyoko; Sato, Hiroki; Kai, Chieko

    2014-12-05

    Recently, several new strains of canine distemper virus (CDV) have been isolated in Japan. To investigate their pathogenesis in dogs, the Yanaka and Bunkyo-K strains were investigated by infecting dogs and determining clinical signs, amount of virus, and antibody responses. The Yanaka strain is avirulent and induced an antibody response. The Bunkyo-K strain induced typical CDV clinical signs in infected dogs and virulence was enhanced by brain passage. Molecular and phylogenetic analyses of H genes demonstrated the Bunkyo-K strains were of a different lineage from Asia-1 group including the Yanaka strain and Asia-2 group that contain recent Japanese isolates, which were recently identified as major prevalent strains worldwide but distinct from old vaccine strains. Based on these data, we tested the ability of the Yanaka strain for vaccination. Inoculation with the Yanaka strain efficiently induced CDV neutralizing antibodies with no clinical signs, and the protection effects against challenge with either old virulent strain or Bunkyo-K strain were equal or greater when compared with vaccination by an original vaccine strain. Thus, the Yanaka strain is a potential vaccine candidate against recent prevalent CDV strains.

  20. "Christian carrying goomies".

    Science.gov (United States)

    1994-01-01

    Dr. Passingan Usurup tells critics of his pragmatic approach on condom promotion that he is a Christian carrying condoms for Christ. He is head of the University of Papua New Guinea Medical Center and is credited with developing an AIDS/HIV policy for the Papua New Guinea Defence Force. The condoms were named Goomy and promoted at launching in 1992 in a blue packet under the slogan "The bond that guards." Goomy was chosen as the name because it is pidgin for rubber, chewing gum, and anything associated with rubber. Blue packets were chosen over the calls of most soldiers for a camouflage design because of its universal appeal as the color of the sea and sky and because it was the preference of women in the airlines. Once firmly ensconced in his role at the University, Usurup plans to develop a policy for students and staff and help to conduct AIDS prevention and education activities on campus. He will encourage students to test for HIV rather than highlighting the gloom and doom of infection and disease.

  1. Light attenuation on Chlorella vulgaris cells

    Science.gov (United States)

    Krol, Tadeusz; Lotocka, Maria

    1993-12-01

    The laboratory measurements of spectrum of light attenuation on phytoplankton particles i.e. monoculture of unicellural green algae Chlorella vulgaris are presented. The measurements were carried out for alive culture and the cultures subjected to chemical (NaOH) or physical (ultrasounds) modification. The distinct changes in the light attenuation spectrum were a result of modification of the internal cell structures.

  2. 牛病毒性腹泻弱毒活疫苗免疫持续期的研究%The Efficacy of the Live Attenuated Bovine Viral Diarrhea Virus SM Vaccine Strain

    Institute of Scientific and Technical Information of China (English)

    张淑琴; 郭利; 王炜; 张亭亭; 吴永旺; 武华

    2012-01-01

    The study was designed to evaluate neutralizing (SN) antibodies against bovine viral diarrhea virus (BVDV) in the calves vaccinated with the live attenuated bovine viral diarrhea virus SM vaccine. A total of 30 healthy calves at weaning were randomly divided into two groups, with 15 calves in vaccinate group and 15 in control group. The attenuated BVDV SM vaccine strain was administrated via intramuscular injection on the neck at a single dose and challenged with a virulent BVDV-JL virus by nasal spray. The blood samples were collected at different time points for monitoring SN antibody titers. The results indicated that the SN antibody titers in the vaccinated calves maintained at a relative high level until 12 month post-vaccination, and the vaccinated calves were effectively protected from the challenge, as detected by the white blood cell count (WBC) and virus shedding. Therefore, the duration of immunity of the vaccine was at lease for 9 months.%为检测牛病毒性腹泻病毒(BVDV)弱毒活疫苗在免疫牛体内抗体产生及其消长规律,评价弱毒疫苗的保护效力,并确定免疫持续期,本试验对免疫试验牛每头颈部肌肉接种BVDV SM株弱毒疫苗104.5TCID50/头,监测血清抗体效价,进行免疫持续期的确定.在疫苗免疫后的6、9和12个月分别抽取5头免疫组和5头对照组牛采用BVDV-JL强毒株进行攻毒试验,每头牛攻毒剂量为6×107.0 TCID50/mL.结果显示疫苗免疫后12个月时血清中和抗体效价仍维持在1∶1048以上,攻毒结果显示3个时间点强毒攻击后,免疫组所有动物白细胞数量都没有下降也没有分离到病毒,而对照组动物白细胞数下降均超过30%,6和9个月动物均分离到病毒,而12个月对照组动物由于年龄大,没有分离到病毒,因此暂定此疫苗的免疫持续期为9个月.

  3. Enhancement of Th1-biased protective immunity against avian influenza H9N2 virus via oral co-administration of attenuated Salmonella enterica serovar Typhimurium expressing chicken interferon-α and interleukin-18 along with an inactivated vaccine

    Directory of Open Access Journals (Sweden)

    Rahman Md

    2012-07-01

    Full Text Available Abstract Background Control of currently circulating re-assorted low-pathogenicity avian influenza (LPAI H9N2 is a major concern for both animal and human health. Thus, an improved LPAI H9N2 vaccination strategy is needed to induce complete immunity in chickens against LPAI H9N2 virus strains. Cytokines play a crucial role in mounting both the type and extent of an immune response generated following infection with a pathogen or after vaccination. To improve the efficacy of inactivated LPAI H9N2 vaccine, attenuated Salmonella enterica serovar Typhimurium was used for oral co-administration of chicken interferon-α (chIFN-α and chicken interleukin-18 (chIL-18 as natural immunomodulators. Results Oral co-administration of S. enterica serovar Typhimurium expressing chIFN-α and chIL-18, prior to vaccination with inactivated AI H9N2 vaccine, modulated the immune response of chickens against the vaccine antigen through enhanced humoral and Th1-biased cell-mediated immunity, compared to chickens that received single administration of S. enterica serovar Typhimurium expressing either chIFN-α or chIL-18. To further test the protective efficacy of this improved vaccination regimen, immunized chickens were intra-tracheally challenged with a high dose of LPAI H9N2 virus. Combined administration of S. enterica serovar Typhimurium expressing chIFN-α and chIL-18 showed markedly enhanced protection compared to single administration of the construct, as determined by mortality, clinical severity, and feed and water intake. This enhancement of protective immunity was further confirmed by reduced rectal shedding and replication of AIV H9N2 in different tissues of challenged chickens. Conclusions Our results indicate the value of combined administration of chIFN-α and chIL-18 using a Salmonella vaccine strain to generate an effective immunization strategy in chickens against LPAI H9N2.

  4. Implication of respiratory syncytial virus (RSV) F transgene sequence heterogeneity observed in Phase 1 evaluation of MEDI-534, a live attenuated parainfluenza type 3 vectored RSV vaccine.

    Science.gov (United States)

    Yang, Chin-Fen; Wang, C Kathy; Malkin, Elissa; Schickli, Jeanne H; Shambaugh, Cindy; Zuo, Fengrong; Galinski, Mark S; Dubovsky, Filip; Tang, Roderick S

    2013-06-10

    MEDI-534 is the first live vectored RSV vaccine candidate to be evaluated in seronegative children. It consists of the bovine parainfluenza virus type 3 (PIV3) genome with substituted human PIV3 F and HN glycoproteins engineered to express RSV F protein. A Phase 1 study of 49 healthy RSV and PIV3 seronegative children 6 to <24 months of age demonstrated an acceptable safety profile at the following doses: 10(4), 10(5) and 10(6)TCID50. After 3 doses of MEDI-534 at 10(6)TCID50, administered at 0, 2 and 4 month intervals, 100% of subjects seroresponded to PIV3, whereas only 50% seroresponded to RSV. To investigate the discordance in seroresponse rates, the RSV F transgene and its flanking non-coding nucleotides were sequenced from shed virus recovered from the nasal washes of 24 MEDI-534-vaccinated children. Eleven out of 24 samples contained no nucleotide changes in the analyzed region. The other 13 samples contained mixtures of variant subpopulations. Fifty-five percent exhibited changes in the transcription termination poly A gene sequences of the upstream bPIV3N gene while 21% had variant subpopulations in the RSV F open reading frame that resulted in pre-mature stop codons. Both types of changes are expected to reduce RSV F expression. Evaluation of the administered vaccine by dual immunofluorescence staining showed ~2.5% variants with low or no RSV F expression while single nucleotide primer extension detected ~1% variation at nucleotide 2045 that resulted in a pre-mature translational termination at codon 85. An association between shedding of variants and lower RSV F serological response was observed but it was not possible to establish a definitive clinical significance due to the small number of subjects in this study.

  5. A simian-human immunodeficiency virus carrying the rt gene from Chinese CRF01_AE strain of HIV is sensitive to nucleoside reverse transcriptase inhibitors and has a highly genetic stability in vivo.

    Science.gov (United States)

    Wang, Wei; Yao, Nan; Ju, Bin; Dong, Zhihui; Cong, Zhe; Jiang, Hong; Qin, Chuan; Wei, Qiang

    2014-06-01

    Human immunodeficiency virus (HIV)-1 subtype CRF01_AE is one of the major HIV-1 subtypes that dominate the global epidemic. However, its drug resistance, associated mutations, and viral fitness have not been systemically studied, because available chimeric simian-HIVs (SHIVs) usually express the HIV-1 reverse transcriptase (rt) gene of subtype B HIV-1, which is different from subtype CRF01_AE HIV-1. In this study, a recombinant plasmid, pRT-SHIV/AE, was constructed to generate a chimeric RT-SHIV/AE by replacing the rt gene of simian immunodeficiency virus (SIVmac239) with the counterpart of Chinese HIV-1 subtype CRF01_AE. The infectivity, replication capacity, co-receptor tropism, drug sensitivity, and genetic stability of RT-SHIV/AE were characterized. The new chimeric RT-SHIV/AE effectively infected and replicated in human T cell line and rhesus peripheral blood mononuclear cells (rhPBMC). The rt gene of RT-SHIV/AE lacked the common mutation (T215I) associated with drug resistance. RT-SHIV-AE retained infectivity and immunogenicity, similar to that of its counterpart RT-SHIV/TC virus following intravenous inoculation in Chinese rhesus macaque. RT-SHIV-AE was more sensitive to nucleoside reverse transcriptase inhibitors (NRTIs) than the RT-SHIV/TC. RT-SHIV/AE was genetically stable in Chinese rhesus macaque. The new chimeric RT-SHIV/AE may be a valuable tool for evaluating the efficacy of the rt-based antiviral drugs against the subtype CRF01_AE HIV-1.

  6. Horizontal transmission of attenuated strain A66 of duck hepatitis virus%鸭肝炎病毒A66弱毒株的水平传播感染

    Institute of Scientific and Technical Information of China (English)

    张小飞; 黄显明; 尹秀凤; 陆承平

    2011-01-01

    取10倍免疫剂量的鸭肝炎弱毒活疫苗(A66株),分别经皮下注射和口服途径接种1日龄易感雏鸭20只,5d后每组取出接种鸭10只分别与20只1d龄易感雏鸭共同饲养进行第1代同居感染试验,5d后取第1代同居感染试验鸭10只再与20只1d龄易感雏鸭共同饲养进行第2代同居感染试验,如此进行5次同居感染试验.定时采集各代次同居感染试验鸭的泄殖腔内容物进行PCR检测,测定鸭肝炎病毒A66弱毒株水平感染能力和排毒情况,并通过对各代次同居感染试验鸭的攻毒试验,测定水平感染的免疫保护作用.结果表明:鸭肝炎弱毒活疫苗(A66株)经皮下注射和口服途径接种雏鸭,均可以通过粪便向体外排泄病毒;同居易感雏鸭可接触感染,感染的雏鸭可获得一定的免疫保护作用;但这种同居感染能力随着同居代次的增加而逐渐减弱,至5代时基本终止.试验结果表明A66毒株可引起雏鸭间的水平传播感染,但这种水平传播能力有限,不会引起毒力返强.%Attenuated strain A66 of duck hepatitis virus was inoculated on 20 one-day-old susceptible ducklings by subcutaneous injection and oral administration, respectively. Five days post-inoculation, 10 ducklings from each group were randomly selected, and cohabitated with 20 new one-day-old ducklings. Ten cohabitated ducklings were randomly selected again five days later for the second generation of cohabitation experiment. Such cohabitation experiments were performed 5 times successively. Anal swab samples were collected from each generation of cohabitated animals at designated time, and were analyzed by polymerase chain reaction (PCR) to determine the horizontal infection ability of the attenuated strain A66 and the viral excretion level by the ducklings. Protective immunity was assessed through attacking different generations of ducklings by cohabitation. The results indicated that inoculation of ducklings with the attenuated

  7. Seringas hipodérmicas descartáveis versus reutilizáveis: estudo de possíveis efeitos sobre o vírus da vacina viva, atenuada contra o sarampo Disposable versus reusable hypodermic syringes: study of feasible effects upon the virus of the live, attenuated measles vaccine

    Directory of Open Access Journals (Sweden)

    Edda de Rizzo

    1986-12-01

    Full Text Available Objetivou-se verificar entre seringas hipodérmicas descartáveis e reutilizáveis qual interfere mais com o vírus vivo presente na vacina contra o sarampo. Vacinas pertencentes a dois lotes foram reconstituídas com os dois tipos de seringas, de modo a formarem dois pools distintos, mantidos à temperatura de +2 a+8°C e protegidos da luz. De cada lote foram realizadas, no mínimo, seis titulações em paralelo, com amostragem a cada hora, de zero a seis horas após reconstituição. A análise estatística dos resultados obtidos nas titulações, feita pelo sistema de retas de regressão demonstrou que embora as vacinas manipuladas com ambos os tipos de seringas apresentassem um decréscimo de título estatisticamente significativo com o decorrer das horas, ele foi bem mais acentuado para as vacinas reconstituídas com seringas reutilizáveis. A menor interferência das descartáveis no título da vacina viva, atenuada contra o sarampo, demonstrou que a preconização e uso desse tipo de seringas pela Secretaria de Estado da Saúde de São Paulo é o ideal e recomendável, por preservar mais a vacina desde a reconstituição até sua administração e, conseqüentemente, a sua eficácia na prevenção dessa infecção.The study was performed in the State of S.Paulo, SP, Brazil, with the purpose of finding out whether reusable (glass and disposable hypodermic syringes used for administration of live attenuated measles vaccines would interfere with their virus. At least six different experiments using two distinct lots of vaccines were carried out. Each time, a lot was reconstituted with reusable and disposable syringes in parallel to form separate pools from which samples were collected hourly from zero to the sixtieth hour after reconstitution for virus titration in monolayers of Vero cells. The straight line regression system chosen for the analysis of the results demonstrated that although vaccines reconstituted with both types of syringes

  8. Attenuated Salmonella typhimurium SV4089 as a potential carrier of oral DNA vaccine in chickens.

    Science.gov (United States)

    Jazayeri, Seyed Davoud; Ideris, Aini; Zakaria, Zunita; Omar, Abdul Rahman

    2012-01-01

    Attenuated Salmonella has been used as a carrier for DNA vaccine. However, in vitro and in vivo studies on the bacteria following transfection of plasmid DNA were poorly studied. In this paper, eukaryotic expression plasmids encoding avian influenza virus (AIV) subtype H5N1 genes, pcDNA3.1/HA, NA, and NP, were transfected into an attenuated Salmonella enteric typhimurium SV4089. In vitro stability of the transfected plasmids into Salmonella were over 90% after 100 generations. The attenuated Salmonella were able to invade MCF-7 (1.2%) and MCF-10A (0.5%) human breast cancer cells. Newly hatched specific-pathogen-free (SPF) chicks were inoculated once by oral gavage with 10(9) colony-forming unit (CFU) of the attenuated Salmonella. No abnormal clinical signs or deaths were recorded after inoculation. Viable bacteria were detected 3 days after inoculation by plating from spleen, liver, and cecum. Fluorescent in situ hybridization (FISH) and polymerase chain reaction (PCR) were carried out for confirmation. Salmonella was not detected in blood cultures although serum antibody immune responses to Salmonella O antiserum group D1 factor 1, 9, and 12 antigens were observed in all the inoculated chickens after 7 days up to 35 days. Our results showed that live attenuated S. typhimurium SV4089 harboring pcDNA3.1/HA, NA, and NP may provide a unique alternative as a carrier for DNA oral vaccine in chickens.

  9. 牛病毒性腹泻病毒弱毒活疫苗免疫持续期的研究%The Efficacy of the Live Attenuated Bovine Viral Diarrhea Virus SM Vaccine Strain

    Institute of Scientific and Technical Information of China (English)

    张淑琴; 郭利; 王伟; 张亭亭; 吴永旺; 武华

    2012-01-01

    The study was designed to evalutate neutralizing(SN) antibodies against bovine viral diarrhea virus(BVDV) in the calves vaccinated with the live attenuated bovine viral diarrhea virus SM vaccine.A total of 30 healthy calves at weaning were randomly divided into two groups,with 15 calves in vaccinate group and 15 in control group.The attenuated BVDV SM vaccine strain was administrated via intramuscular injection on the neck at a single dose and challenged with a virulent BVDV-JL virus by nasal spray.The blood sample were collected at different time points for monitoring SN antibody titers.The results indicated that the SN antibody titers in the vaccinated calves maintained at a relative high level until 12 month post-vaccination,and the vaccinated calves were effectively protected from the challenge,as detected by the white blood cell count(WBC) and,virus shedding.therefore,the duration of immunity of the vaccine was at lease for 9 months.%为检测牛病毒性腹泻病毒(BVDV)弱毒活疫苗在免疫牛体内抗体产生及其消长规律,评价弱毒疫苗的保护效力,并确定免疫持续期,本试验对免疫试验牛每头颈部肌肉接种BVDV SM株弱毒疫苗104.5TCID50,监测血清抗体效价,进行免疫持续期的确定。在疫苗免疫后的6个月、9个月和12个月,分别抽取5头免疫组和5头对照组牛,采用BVDV-JL强毒株进行攻毒试验,每头牛攻毒剂量为6×107.0TCID50/mL。结果显示疫苗免疫后12个月时血清中和抗体效价仍维持在1∶1048以上。攻毒结果显示,在3个不同时间点进行强毒攻击后,免疫组所有动物白细胞数量都没有下降也没有分离到病毒,而对照组动物白细胞数下降均超过30%,6个月和9个月时动物血清中均能分离到病毒,而12个月对照组动物由于年龄大,没有分离到病毒,因此暂定此疫苗的免疫持续期为9个月。

  10. Safety and Efficacy of an Attenuated Infectious Bovine Rhinotracheitis Virus Vaccine%牛传染性鼻气管炎活疫苗安全性和免疫保护效果研究

    Institute of Scientific and Technical Information of China (English)

    冷雪; 郭利; 张淑琴; 武华

    2011-01-01

    The attenuated infectious bovine rhinotracheitis virus (IBRV) vaccine was tested for its safety and efficacy in host animals. In order to test the safety of the vaccine,one-month-old calves,6 to 8 month old calves,and heifers were inoculated with 2 mL (10 doses) of the vaccine. In the efficacy study,6 to 8 month old calves were vaccinated with single dose 1 mL of the vaccine. Then, the animals were challenged with a virulent challenge virus on 28 days post vaccination for immunogenicity of the vaccine. The results revealed that the calves of different ages did not show any clinical diseases post-vaccination. The newborn calves are normal and healthy,and no abortion,stillbirth or mummy fetus occurred in the pregnant cows. Immunogenicity study demonstrated that the vaccine provided five fifths protection to calves against the IBRV infection and clinical diseases caused by the challenge. The results indicated that the vaccine is safe and have a good efficacy to host animals.%本试验使用牛传染性鼻气管炎弱毒活疫苗进行安全性和免疫保护效果研究,将该疫苗分别接种1月龄犊牛、6~8月龄牛及后备母牛,接种剂量为2mL(10头份),检验疫苗安全性.将疫苗接种6~8月龄牛,接种剂量为1 mL(1头份),疫苗接种后28 d使用检验用强毒进行攻毒,检验疫苗对攻击用强毒的保护效力.结果表明,不同月龄牛接种疫苗后体温正常,无任何临床可见异常,后备母牛接种疫苗后精神状态及食欲均良好,无流产、死胎及木乃伊胎出现.疫苗接种牛对强毒攻击可产生较好的抵抗力,攻毒保护率达5/5.研究结果表明,该疫苗对牛安全,且免疫保护效果良好.

  11. Modulation of systemic and mucosal immunity against an inactivated vaccine of Newcastle disease virus by oral co-administration of live attenuated Salmonella enterica serovar Typhimurium expressing chicken interleukin-18 and interferon-α.

    Science.gov (United States)

    Rahman, Md Masudur; Uyangaa, Erdenebelig; Han, Young Woo; Hur, Jin; Park, Sang-Youel; Lee, John Hwa; Kim, Koanhoi; Eo, Seong Kug

    2015-04-01

    Newcastle disease (ND) is a highly contagious disease of chickens causing significant economic losses worldwide. Due to limitations in the efficacy against currently circulating ND viruses, existing vaccination strategies require improvements, and incorporating immunomodulatory cytokines with existing vaccines might be a novel approach. Here, we investigated the systemic and mucosal immunomodulatory properties of oral co-administration of chicken interleukin-18 (chIL-18) and chicken interferon-α (chIFN-α) using attenuated Salmonella enterica serovar Typhimurium on an inactivated ND vaccine. Our results demonstrate that oral administration of S. enterica serovar Typhimurium expressing chIL-18 or chIFN-α provided enhanced systemic and mucosal immune responses, as determined by serum hemagglutination inhibition antibody and NDV Ag-specific IgG as well as NDV Ag-specific IgA in lung and duodenal lavages of chickens immunized with inactivated ND vaccine via the intramuscular or intranasal route. Notably, combined oral administration of S. enterica serovar Typhimurium expressing chIL-18 and chIFN-α significantly enhanced systemic and mucosal immunity in ND-vaccinated chickens, compared to single administration of S. enterica serovar Typhimurium expressing chIL-18 or chIFN-α. In addition, oral co-administration of S. enterica serovar Typhimurium expressing chIL-18 and chIFN-α provided enhanced NDV Ag-specific proliferation of peripheral blood mononuclear cells and Th1-biased cell-mediated immunity, compared to single administration of either construct. Therefore, our results provide valuable insight into the modulation of systemic and mucosal immunity by incorporation of immunomodulatory chIL-18 and chIFN-α using Salmonella vaccines into existing ND vaccines.

  12. Temperature-sensitive mutants of enterovirus 71 show attenuation in cynomolgus monkeys.

    Science.gov (United States)

    Arita, Minetaro; Shimizu, Hiroyuki; Nagata, Noriyo; Ami, Yasushi; Suzaki, Yuriko; Sata, Tetsutaro; Iwasaki, Takuya; Miyamura, Tatsuo

    2005-05-01

    Enterovirus 71 (EV71) is one of the major causative agents of hand, foot and mouth disease and is sometimes associated with serious neurological disorders. In this study, an attempt was made to identify molecular determinants of EV71 attenuation of neurovirulence in a monkey infection model. An infectious cDNA clone of the virulent strain of EV71 prototype BrCr was constructed; temperature-sensitive (ts) mutations of an attenuated strain of EV71 or of poliovirus (PV) Sabin vaccine strains were then introduced into the infectious clone. In vitro and in vivo phenotypes of the parental and mutant viruses were analysed in cultured cells and in cynomolgus monkeys, respectively. Mutations in 3D polymerase (3D(pol)) and in the 3' non-translated region (NTR), corresponding to ts determinants of Sabin 1, conferred distinct temperature sensitivity to EV71. An EV71 mutant [EV71(S1-3')] carrying mutations in the 5' NTR, 3D(pol) and in the 3' NTR showed attenuated neurovirulence, resulting in limited spread of virus in the central nervous system of monkeys. These results indicate that EV71 and PV1 share common genetic determinants of neurovirulence in monkeys, despite the distinct properties in their original pathogenesis.

  13. On fast carry select adders

    Science.gov (United States)

    Shamanna, M.; Whitaker, S.

    1992-01-01

    This paper presents an architecture for a high-speed carry select adder with very long bit lengths utilizing a conflict-free bypass scheme. The proposed scheme has almost half the number of transistors and is faster than a conventional carry select adder. A comparative study is also made between the proposed adder and a Manchester carry chain adder which shows that the proposed scheme has the same transistor count, without suffering any performance degradation, compared to the Manchester carry chain adder.

  14. On fast carry select adders

    Science.gov (United States)

    Shamanna, M.; Whitaker, S.

    This paper presents an architecture for a high-speed carry select adder with very long bit lengths utilizing a conflict-free bypass scheme. The proposed scheme has almost half the number of transistors and is faster than a conventional carry select adder. A comparative study is also made between the proposed adder and a Manchester carry chain adder which shows that the proposed scheme has the same transistor count, without suffering any performance degradation, compared to the Manchester carry chain adder.

  15. Safety of a Live Attenuated Infectious Bovine Rhinotracheitis Vaccine IBRV LNM Strain

    Institute of Scientific and Technical Information of China (English)

    Guo; Li; Wang; Wei; Zhang; Shuqin; Cheng; Shipeng; Wu; Hua

    2014-01-01

    The paper was to evaluate the vaccine safety,and to prevent public health risk due to virus spread,the approach vaccination of was adopted in this research; and neck intramuscular injection of IBRV LNM attenuated vaccine strain was carried out. Blind passage for three generations in animal has tested the reversion risk to virulence. A total of 14 healthy and weaning cows at 6- 8 month old were divided into three groups. The 1st reversion of virulence trials used 105. 0TCID50/mL neck intramuscular injection of IBRV LNM attenuated vaccine strain. Then,the nose swab samples were collected for continuous 14 days. After passed through 0. 45 μm filter membrane,nasal swabs mixture was prepared as the virulence test inoculum for next generation. The body temperature was detected and clinical observation was carried out for continuous 14 days after inoculation. The inoculation dose was 1ml / cattle. Blood was collected on the 0 and 14 thdays of animal vaccination. After serum isolation,it was used for the antibody detection of serum. Research results showed that no virus was isolated from the nasal swabs from the F2 generation; vaccinated animals did not show any clinical signs of IBR; serological testing of IBRV antibody was negative,which indicated that the strain-inoculated animals did had reversion of virulence in all three generations.

  16. Photonic Crystal Fiber Attenuator

    Institute of Scientific and Technical Information of China (English)

    Joo; Beom; Eom; Hokyung; Kim; Jinchae; Kim; Un-Chul; Paek; Byeong; Ha; Lee

    2003-01-01

    We propose a novel fiber attenuator based on photonic crystal fibers. The difference in the modal field diameters of a conventional single mode fiber and a photonic crystal fiber was used. A variable optical attenuator was also achieved by applying macro-bending on the PCF part of the proposed attenuator

  17. 乙型脑炎减毒活疫苗细菌内毒素检查方法及质量标准的建立%Establishment of the inspection methods and quality criteria for bacterial endotoxin of live-attenuated vaccine of encephalitis B virus

    Institute of Scientific and Technical Information of China (English)

    李红芳; 陈继军; 王建军; 王伟; 杨博涵; 李守丽; 邹勇

    2009-01-01

    目的 建立乙型脑炎减毒活疫苗细菌内毒素检测的方法及质量标准.方法 参照(三部)中细菌内毒素检查法检测,并与家兔热原实验结果进行对比.结果 使用凝胶限量法检测乙型脑炎减毒活疫苗细菌内毒素,限值为40 EU/mL,即将样品稀释至160倍,在该稀释度下样品对试验没有干扰.结论 该方法简便、灵敏、结果可靠,可用于乙型脑炎减毒活疫凿中间产品的细菌内毒素检查.%Objective To establish the inspection methods and quality criteria for bacterial en- dotoxin of live-attenuated vaccine of encephalitis B virus. Methods The inspecting method for bacterial endotoxin from Pharmacopoeia of the People's Republic of China (3 ed) was employed and the results were compared with the results of rabbit pyrogen test. Results Bacterial endo- toxin of live-attenuated vaccine of encephalitis B virus was detected by gel-clot limit test,the detection limit was 40 EU/mL,namely,160-fold dilution of the sample. In this dilution,no inter- ference of samples to the endotoxin test was observed. Conclusion The method is convenient, sensitive and reliable and may be used for bacterial endotoxin inspection of intermediate products of live-attenuated vaccine of encephalitis B virus.

  18. An Analysis of English Carrie

    Institute of Scientific and Technical Information of China (English)

    孙淑珍

    2004-01-01

    @@ Chapter Ⅰ Introduction Sitting in the rocking chair,Carrie dreams her future.This is the deep impression the novel"Sister Carrie"gives us,which is written by Theodore Dreiser(1871-1945),the great American realism writer.

  19. Tracer attenuation in groundwater

    Science.gov (United States)

    Cvetkovic, Vladimir

    2011-12-01

    The self-purifying capacity of aquifers strongly depends on the attenuation of waterborne contaminants, i.e., irreversible loss of contaminant mass on a given scale as a result of coupled transport and transformation processes. A general formulation of tracer attenuation in groundwater is presented. Basic sensitivities of attenuation to macrodispersion and retention are illustrated for a few typical retention mechanisms. Tracer recovery is suggested as an experimental proxy for attenuation. Unique experimental data of tracer recovery in crystalline rock compare favorably with the theoretical model that is based on diffusion-controlled retention. Non-Fickian hydrodynamic transport has potentially a large impact on field-scale attenuation of dissolved contaminants.

  20. Carrying Capacity:An Overview

    Institute of Scientific and Technical Information of China (English)

    Chen Shaofeng

    2004-01-01

    The concept of carrying capacity is derived from ecology, with widespread contentions of its theoretical connotations and applications in the international academic community, especially the impact of human activities on the environment.Disputes on carrying capacity have been occurring not only among biologists and ecologists, but also among mainstream economists. Based on their efforts,the author makes an attempt to describe its origin,connotations, problems, measurement, and at the same time note the latest international progress in this field.

  1. Cell culture attenuation eliminates rMd5deltaMeq-induced bursal and thymic atrophy and renders the mutant virus as an effective and safe vaccine against Marek's disease

    Science.gov (United States)

    Marek’s disease virus (MDV) encodes a basic leucine zipper oncoprotein, meq, which structurally resembles jun/fos family of transcriptional activators. It has been clearly demonstrated that deletion of meq results in loss of transformation and oncogenic capacity of MDV. The rMd5'meq virus provided s...

  2. 狂犬病病毒CTN-181减毒株在豚鼠颌下腺的繁殖动态及其低毒力克隆株的筛选研究%Study on the attenuated rabies virus CTN-181 in the submandibular gland of guinea pigs and the low virulence clones from the submandibular gland

    Institute of Scientific and Technical Information of China (English)

    石磊泰; 邹剑; 俞永新; 王玲; 曹守春; 董关木; 李玉华

    2015-01-01

    目的 了解狂犬病病毒减毒株CTN-181在豚鼠颌下腺的繁殖动态并获得毒力更低的病毒纯化克隆株.方法 将CTN-181经刚离乳豚鼠颈部皮下注射,分别于1、2、3和4d取颌下腺分离狂犬病病毒,测定各天次颌下腺内的病毒滴度.用滴度高的病毒液进行下一次豚鼠颌下腺传代,连续传3代.将第3代颌下腺传代的病毒液在BHK21细胞上进行空斑试验,挑选单个病毒克隆,以3周龄小鼠脑内接种测病毒毒力.筛选对小鼠不致病的克隆株进一步测定其对乳鼠的脑内毒力,并以乳鼠脑内传代和豚鼠颌下腺传代检测其遗传稳定性.结果 CTN-181在豚鼠颌下腺能短暂轻度繁殖,通过颌下腺传代后病毒毒力明显有回升.获得19个病毒克隆,不同克隆病毒的毒力不同,为0~3.16 lg LD50;3株脑内无致病力的克隆株对乳鼠的毒力亦有减弱;乳鼠脑内和颌下腺回传后毒力无回升返祖,即传代后的病毒对小鼠均无致病力.结论 CTN-181母株对3周龄小鼠仍存在低水平毒力,经豚鼠颌下腺传代后毒力十分不稳定.筛选到的3株克隆病毒较其母株的毒力更低,遗传稳定性更高,更适合作为狂犬病兽用口服疫苗候选株.%Objective To understand the stability of an attenuated rabies virus strain CTN-181 and to obtain more attenuated and stable virus strains from the CTN-181 strain.Methods The CTN-181 virus was inoculated into the submandibular glands of guinea pigs subcutaneously.The glands were harvested on day 1,2,3 and 4 after inoculation,then the virus contents and virulence in 3-week mice were evaluated.Three generations of the submandibular gland passage were made and the gland virus sample from the third passage of the guinea pigs was used for plaque cloning.Plaque clone viruses were tested for their neurovirulence in 3-week mice or suckling mice,and the attenuation stability was performed by inoculation passage in suckling mice and submandibular gland passages

  3. Naturalistic Elements in Sister Carrie

    Institute of Scientific and Technical Information of China (English)

    刘艳晖

    2007-01-01

    @@ Theodore Dreiser is considered to be a controversial writer.His first novel.Sister Carrie makes a new way of presenting re-ality.This paper discusses the naturalistic elements from the de-tailed description of the environment in that society.

  4. Carrying photosynthesis genes increases ecological fitness of cyanophage in silico.

    Science.gov (United States)

    Hellweger, Ferdi L

    2009-06-01

    Several viruses infecting marine cyanobacteria carry photosynthesis genes (e.g. psbA, hli) that are expressed, yield proteins (D1, HLIP) and help maintain the cell's photosynthesis apparatus during the latent period. This increases energy and speeds up virus production, allowing for a reduced latent period (a fitness benefit), but it also increases the DNA size, which slows down new virus production and reduces burst size (a fitness cost). How do these genes affect the net ecological fitness of the virus? Here, this question is explored using a combined systems biology and systems ecology ('systems bioecology') approach. A novel agent-based model simulates individual cyanobacteria cells and virus particles, each with their own genes, transcripts, proteins and other properties. The effect of D1 and HLIP proteins is explicitly considered using a mechanistic photosynthesis component. The model is calibrated to the available database for Prochlorococcus ecotype MED4 and podovirus P-SSP7. Laboratory- and field-scale in silico survival, competition and evolution (gene packaging error) experiments with wild type and genetically engineered viruses are performed to develop vertical survival and fitness profiles, and to determine the optimal gene content. The results suggest that photosynthesis genes are nonessential, increase fitness in a manner correlated with irradiance, and that the wild type has an optimal gene content.

  5. Coat protein mutations in an attenuated Cucumber mosaic virus encoding mutant 2b protein that lacks RNA silencing suppressor activity induces chlorosis with photosynthesis gene repression and chloroplast abnormalities in infected tobacco plants.

    Science.gov (United States)

    Mochizuki, Tomofumi; Yamazaki, Ryota; Wada, Tomoya; Ohki, Satoshi T

    2014-05-01

    In tobacco plants, the Cucumber mosaic virus (CMV) pepo strain induces mosaic symptoms, including pale green chlorosis and malformed tissues. Here, we characterized the involvement of 2b protein and coat protein (CP) in the development of mosaic symptoms. A 2b mutant (R46C) that lacks viral suppressor of RNA silencing (VSR) activity showed an asymptomatic phenotype with low levels of virus accumulation. Tomato spotted wilt virus NSs protein did not complement the virulence of the R46C, although it did restore high-level virus accumulation. However, R46C mutants expressing mutated CP in which the amino acid P129 was mutated to A, E, C, Q, or S induced chlorosis that was associated with reduced expression of chloroplast and photosynthesis related genes (CPRGs) and abnormal chloroplasts with fewer thylakoid membranes. These results suggest that the CP of the CMV pepo strain acquires virulence by amino acid mutations, which causes CPRG repression and chloroplast abnormalities.

  6. Pathogenicity and immunogenicity of attenuated, nef-deleted HIV-1 strains in vivo

    Directory of Open Access Journals (Sweden)

    Wesselingh Steven L

    2007-09-01

    Full Text Available Abstract In efforts to develop an effective vaccine, sterilizing immunity to primate lentiviruses has only been achieved by the use of live attenuated viruses carrying major deletions in nef and other accessory genes. Although live attenuated HIV vaccines are unlikely to be developed due to a myriad of safety concerns, opportunities exist to better understand the correlates of immune protection against HIV infection by studying rare cohorts of long-term survivors infected with attenuated, nef-deleted HIV strains such as the Sydney blood bank cohort (SBBC. Here, we review studies of viral evolution, pathogenicity, and immune responses to HIV infection in SBBC members. The studies show that potent, broadly neutralizing anti-HIV antibodies and robust CD8+ T-cell responses to HIV infection were not necessary for long-term control of HIV infection in a subset of SBBC members, and were not sufficient to prevent HIV sequence evolution, augmentation of pathogenicity and eventual progression of HIV infection in another subset. However, a persistent T-helper proliferative response to HIV p24 antigen was associated with long-term control of infection. Together, these results underscore the importance of the host in the eventual outcome of infection. Thus, whilst generating an effective antibody and CD8+ T-cell response are an essential component of vaccines aimed at preventing primary HIV infection, T-helper responses may be important in the generation of an effective therapeutic vaccine aimed at blunting chronic HIV infection.

  7. Rational Design of Human Metapneumovirus Live Attenuated Vaccine Candidates by Inhibiting Viral mRNA Cap Methyltransferase

    Science.gov (United States)

    Zhang, Yu; Wei, Yongwei; Zhang, Xiaodong; Cai, Hui; Niewiesk, Stefan

    2014-01-01

    ABSTRACT The paramyxoviruses human respiratory syncytial virus (hRSV), human metapneumovirus (hMPV), and human parainfluenza virus type 3 (hPIV3) are responsible for the majority of pediatric respiratory diseases and inflict significant economic loss, health care costs, and emotional burdens. Despite major efforts, there are no vaccines available for these viruses. The conserved region VI (CR VI) of the large (L) polymerase proteins of paramyxoviruses catalyzes methyltransferase (MTase) activities that typically methylate viral mRNAs at positions guanine N-7 (G-N-7) and ribose 2′-O. In this study, we generated a panel of recombinant hMPVs carrying mutations in the S-adenosylmethionine (SAM) binding site in CR VI of L protein. These recombinant viruses were specifically defective in ribose 2′-O methylation but not G-N-7 methylation and were genetically stable and highly attenuated in cell culture and viral replication in the upper and lower respiratory tracts of cotton rats. Importantly, vaccination of cotton rats with these recombinant hMPVs (rhMPVs) with defective MTases triggered a high level of neutralizing antibody, and the rats were completely protected from challenge with wild-type rhMPV. Collectively, our results indicate that (i) amino acid residues in the SAM binding site in the hMPV L protein are essential for 2′-O methylation and (ii) inhibition of mRNA cap MTase can serve as a novel target to rationally design live attenuated vaccines for hMPV and perhaps other paramyxoviruses, such as hRSV and hPIV3. IMPORTANCE Human paramyxoviruses, including hRSV, hMPV, and hPIV3, cause the majority of acute upper and lower respiratory tract infections in humans, particularly in infants, children, the elderly, and immunocompromised individuals. Currently, there is no licensed vaccine available. A formalin-inactivated vaccine is not suitable for these viruses because it causes enhanced lung damage upon reinfection with the same virus. A live attenuated vaccine

  8. LGP2 downregulates interferon production during infection with seasonal human influenza A viruses that activate interferon regulatory factor 3.

    Science.gov (United States)

    Malur, Meghana; Gale, Michael; Krug, Robert M

    2012-10-01

    LGP2, a member of the RIG-I-like receptor family, lacks the amino-terminal caspase activation recruitment domains (CARDs) required for initiating the activation of interferon regulatory factor 3 (IRF3) and interferon (IFN) transcription. The role of LGP2 in virus infection is controversial, and the only LGP2 experiments previously carried out with mammalian influenza A viruses employed an attenuated, mouse-adapted H1N1 A/PR/8/34 (PR8) virus that does not encode the NS1 protein. Here we determine whether LGP2 has a role during infection with wild-type, nonattenuated influenza A viruses that have circulated in the human population, specifically two types of seasonal influenza A viruses: (i) H3N2 and H1N1 viruses that activate IRF3 and IFN transcription and (ii) recent H1N1 viruses that block these two activations. In human cells infected with an H3N2 virus that activates IRF3, overexpression of LGP2 or its repressor domain decreased STAT1 activation and IFN-β transcription approximately 10-fold. Overexpression of LGP2 also caused a 10-fold decrease of STAT1 activation during infection with other seasonal influenza A viruses that activate IRF3. Using LGP2(+/+) and LGP2(-/-) mouse cells, we show that endogenous LGP2 decreased IFN production during H3N2 virus infection 3- to 4-fold. In contrast, in both mouse and human cells infected with H1N1 viruses that do not activate IRF3, LGP2 had no detectable role. These results demonstrate that LGP2 downregulates IFN production during infection by seasonal influenza A viruses that activate IRF3 and IFN transcription. It is intriguing that LGP2, a host protein induced during influenza A virus infection, downregulates the host antiviral IFN response.

  9. Satellite RNAs and Satellite Viruses.

    Science.gov (United States)

    Palukaitis, Peter

    2016-03-01

    Satellite RNAs and satellite viruses are extraviral components that can affect either the pathogenicity, the accumulation, or both of their associated viruses while themselves being dependent on the associated viruses as helper viruses for their infection. Most of these satellite RNAs are noncoding RNAs, and in many cases, have been shown to alter the interaction of their helper viruses with their hosts. In only a few cases have the functions of these satellite RNAs in such interactions been studied in detail. In particular, work on the satellite RNAs of Cucumber mosaic virus and Turnip crinkle virus have provided novel insights into RNAs functioning as noncoding RNAs. These effects are described and potential roles for satellite RNAs in the processes involved in symptom intensification or attenuation are discussed. In most cases, models describing these roles involve some aspect of RNA silencing or its suppression, either directly or indirectly involving the particular satellite RNA.

  10. Comparision of viremia formation between guinea-pigs infected with wild and attenuated ( SA14-14-2) Japanese encephalitis viruses%乙型脑炎野毒株和弱毒株(SA14-14-2)在豚鼠体内的病毒血症比较试验

    Institute of Scientific and Technical Information of China (English)

    刘欣玉; 俞永新; 徐宏山; 梁国栋; 王环宇; 贾丽丽; 董关木

    2010-01-01

    Objective To study the viremia formation in guinea-pigs infected with wild type and attenuated Japanese encephalitis virus (JEV). Methods Guniea pigs were inoculated intraperitoneally with different wild JEV strains and the attenuated vaccine strain and its parent virulent strain. Viremia was detected on different days following virus inoculation. Results All the guinea-pigs inoculated with the wild JEV strains induced different levels of viremia ( 1.00-3.40 lg pfu) on the 1 st and 3rd day post inoculation.Using a virus titer of 104 pfu for inoculation, the animals inoculated with the SA14 parent strain induced relatively high viremia (1024-10 3.4 pfu), however no viremia coulds be detected on any tested days.Conclusion The degree of viremia in guinea pigs can be used as a new method to evaluate the attenuation of JEV.%目的 利用豚鼠病毒血症的产生强度对乙型脑炎野毒株和弱毒株病毒毒力进行评价.方法 以不同乙脑野毒株和减毒株及其母株病毒分别接种豚鼠,观察不同时间产生病毒血症的水平.结果 接种后1 d和3 d,不同乙脑野毒株均可检测到不同水平的病毒血症(1.00~3.40 lg pfu),以相同滴度(104pfu)的病毒接种豚鼠时,疫苗株母株SA14产生较高水平的毒血症(2.41~3.40 lg pfu)并至少持续3 d,而SA14-14-2疫苗株未产生毒血症.结论 豚鼠病毒血症的产生强度可以作为一种新的方法对乙型脑炎病毒的减毒和疫苗株的毒力进行评价.

  11. Landing gear noise attenuation

    Science.gov (United States)

    Moe, Jeffrey W. (Inventor); Whitmire, Julia (Inventor); Kwan, Hwa-Wan (Inventor); Abeysinghe, Amal (Inventor)

    2011-01-01

    A landing gear noise attenuator mitigates noise generated by airframe deployable landing gear. The noise attenuator can have a first position when the landing gear is in its deployed or down position, and a second position when the landing gear is in its up or stowed position. The noise attenuator may be an inflatable fairing that does not compromise limited space constraints associated with landing gear retraction and stowage. A truck fairing mounted under a truck beam can have a compliant edge to allow for non-destructive impingement of a deflected fire during certain conditions.

  12. Effect of attenuated viral vaccines on suckling mice infected with LCMV.

    Science.gov (United States)

    Csatáry, L K; Szeri, I; Bános, Z; Anderlik, P; Nász, I

    1986-01-01

    A single intraperitoneal treatment with live Newcastle Disease Virus (NDV) containing attenuated NDV vaccine, and with live infectious bursal disease virus (IBDV) containing attenuated IBDV vaccine, one day before intracerebral infection with lymphocytic choriomeningitis virus (LCMV) increased, whereas a similar treatment with inactivated NDV or IBDV vaccine did not influence the death rate of suckling mice from experimental lymphocytic choriomeningitis. Thus the attenuated live vaccine stimulated, whereas the inactivated ones failed to affect the cell-mediated immune response to LCMV. Control studies set up with the supernatant of plain tissue culture routinely used for the propagation of IBDV have shown that unlike the attenuated NDV vaccine, the immunostimulatory action is associated not so much with the virus itself, as with an as yet unidentified component of the tissue culture supernatant.

  13. 麻疹减毒活疫苗接种偶合麻疹野病毒感染病例的麻疹病毒基因特征分析%Genetic character of wild measles virus causing an accidental case after immunization with live attenuated measles vaccine

    Institute of Scientific and Technical Information of China (English)

    张帆; 周剑惠; 陈超; 徐鑫; 王爽; 常新; 魏雷雷; 于佳动

    2012-01-01

    目的 分析1例接种麻疹减毒活疫苗第9天出现麻疹样症状病例的麻疹病毒基因特征,以确定是麻疹疫苗相关病例还是偶合麻疹野病毒感染.方法 提取该病例咽拭子标本核酸,采用RT-PCR法扩增麻疹病毒核蛋白(Nucleoprotein,NP)基因羧基末端450个核苷酸片段后测序,分析其与全球24个基因型麻疹野病毒代表株、中国疫苗株(Shanghai-191)基因的亲缘关系以及核苷酸、氨基酸序列同源性.结果 该病例感染的病毒属于H1a基因亚型麻疹野病毒.与中国H1基因型麻疹野病毒流行株代表株核苷酸和氨基酸序列的同源性较高,分别为97.5% ~ 99.5%和96.6%,而与麻疹病毒中国疫苗株(Shanghai- 191)核苷酸和氨基酸序列同源性较低,分别仅为91.2%和86.7%.结论 该例接种麻疹减毒活疫苗后出现麻疹样症状的病例为偶合H1基因型麻疹野病毒感染所致,非麻疹疫苗相关病例.%Objective To analyze the genetic character of measles virus causing a measles-like case on day 9 after immunization with live attenuated measles vaccine so as to confirm the case as vaccine-associated one or accidental one caused by wild measles virus. Methods Nucleic acids were extracted from the throat swab of the patient and sequenced after amplification of 450 nucleotides at C-terminus of measles virus nucleoprotein (NP) by RT-PCR, based on which the genetic relationship as well as homologies of nucleotides and amino acids of the strain to the representational strains of wild measles virus strains of all the 24 genotypes and Chinese vaccine strain (Shanghai-191) were analyzed. Results The virus causing the case was wild measles virus of subgenotype Hal, of which the homologies of nucleotides and amino acids were 97. 5% ~ 99. 5% and 96. 6% respectively to those of the representational strain of wild measles virus of genotype H1 epidemic in China, while were only 91. 2% and 86. 7% respectively to those of Shanghai-191

  14. Competitive capacity of HIV-1 strains carrying M184I or Y181I drug-resistant mutations

    Institute of Scientific and Technical Information of China (English)

    LI Jue; LI Lin; LI Han-ping; ZHUANG Dao-min; LIU Si-yang; LIU Yong-jian; BAO Zuo-yi; WANG Zheng; LI Jing-yun

    2009-01-01

    Background Virus with nucleoside reverse transcriptase inhibitors (NRTIs) or nonnucleoside reverse transcdptase inhibitors (NNRTIs) resistant mutations show different evolution tendencies when the anti-viral therapies are interrupted. Understanding the replication fitness of drug-resistant virus is important for the study of the prevalence of drug-resistance. For this purpose, we characterized the replication capacity of HIV-1 virus carrying lamivudine (3TC) or nevirapine (NVP) resistant mutations.Methods 3TC and NVP resistant variants were induced in vitro by selecting wild type virus in the presence of drugs. For the competitive replication assay, drug-resistant variants were cocultured with wild-type virus in the presence or absence of drugs. The ratios of the viral species were determined over time by using a real-time RT-PCR-based assay. Results 3TC-resistant (M184I mutation) and NVP-resistant (Y181I mutation) virus should be selected in vitro in two different ways. The competitive replication assay showed that the ratio of virus carrying a M184I mutation increased from 98.8%, while the wild type virus decreased to 1.2% after 4 passages in the presence of 3TC; the percentage of virus carrying the Y181I mutation increased to 90.5%, while wild type virus decreased to 9.5% in the presence of NVP. In the absence of drugs, the ratio of virus carrying the M184I mutation decreased to 5.3%, while wild type virus increased to 94.7%; the ratio of virus carrying Y181I increased to 75%, while wild type virus decreased to 25% after 4 passages.Conclusions The NVP-resistant virus is fitter than wild type virus even in the absence of NVP that may be the reason that NNRTIs-resistant virus is spreading quickly.

  15. Canine Distemper Virus Utilizes Different Receptors to Infect Chicken Embryo Fibroblasts and Vero cells

    Institute of Scientific and Technical Information of China (English)

    Jun Chen; Xiu Liang; Pei-fu Chen

    2011-01-01

    Inducing animal viruses to adapt to chicken embryos or chicken embryo fibroblasts(CEF)is a common method to develop attenuated live vaccines with full security.Canine distemper virus(CDV)also does this,but the mechanisms and particular receptors remain unclear.Virus overlay protein blot assays were carried out on CEF membrane proteins,which were extracted respectively with a Mem-PERTM kit,a radioimmunoprecipitation assay buffer or a modified co-immunoprecipitation method,and revealed a common 57 kDa positive band that differed from the 42-kDa positive band in Vero cells and also from those receptors reported in lymphocytes and293 cells,indicating a receptor diversity of CDV and the possibility of the 57-kDa protein acting as a receptor that is involved in adaptive infection of CDV Kunming strain to CEF.

  16. 携带兔斯氏艾美耳球虫MIC-5基因减毒鼠伤寒沙门菌活疫苗的安全性、稳定性与免疫原性%Safety, stability and immunogenicity of attenuated Salmonella typhimurium carrying MIC-5 gene of Eimeria stieda

    Institute of Scientific and Technical Information of China (English)

    孟庆玲; 乔军; 才学鹏; 闫鸿斌; 田广孚; 骆学农

    2011-01-01

    对携带兔斯氏艾美耳球虫微线蛋白-5基因(MIC-5)真核表达质粒asd-pBMIC-5-IL-15的减毒鼠伤寒沙门菌X4550(X4550/asd-pBMIC-5-IL-15)进行了安全性、稳定性与免疫原性试验.结果显示,重组菌在109CFU剂量以下对家兔安全;连续培养30代重组菌,重组表达质粒可稳定存在于X4550内,具有良好的遗传稳定性;用重组菌2次免疫动物后,既能诱导机体产生抗兔斯氏艾美耳球虫抗体,也能显著增强淋巴细胞增殖水平,抗球虫指数为164.4.试验表明,减毒沙门菌介导的兔球虫调节型DNA疫苗具有良好的安全性、稳定性和免疫原性.%The security,stability and immunogenicity trials of recombinant Salmonella typhimurium X4550 carrying rabbit's Eimeria stiedai MIC-5 gene expression plasmid asd-pBMIC-5-IL-15 (X4550/asd-pBMIO5-IL-15) was assayed in this study. The results showed that the 109 CFU inoculation dose was safe in the experimental rabbits. The recombinant plasmid existed stably in X4550 after 30 passages, which displayed a good genetic stability. After two immunizations in rabbits, the recombinant Salmonella typhimurium induced the specific antibodies against rabbit Eimeria stiedai and significantly improved the level of lymphocyte proliferation. The anti-coccidia index reached 164. 4. The results indicated that the regulation DNA vaccine mediated by Salmonella had a good security,stability and immunogenicity against rabbit Eimeria stiedai.

  17. Study of biologic characteristics on Epstein-Barr virus transformed B lymphocytes carrying hepatitis C virus type Ⅱ%丙型肝炎病毒Ⅱ型阳性PBMC永生化细胞株的生物学特性

    Institute of Scientific and Technical Information of China (English)

    程计林; 仝文斌; 冯百芳; 陶其敏; 朱伟; 刘宝玲; 陈良标; 陈佩兰

    2001-01-01

    Objective To study persistence and replication of hepatitis C virus (HCV) in the patients′ peripheral blood mononuclear cells (PBMC) transformed by Epstein-Barr virus (EBV) in vitro and in order to explore the possibility of establishing a cell line for HCV reproduction. Methods EBV infected peripheral B lymphocytes from one patient with HCV positive of PBMC were transformed into permanent lymphoblastoid cell lines (LCL). The general and special biology characteristics of LCL were studied by cell culture, chromosome banding technique, flow fluorescent-activated cell sorter, reverse transcription-polymerase chain reaction (RT-PCR), in situ PCR, immunohistochemistry and electronic microscopy. Results 1. G-banded karyotype of the LCL was 47, XX, +mar, CD19 and CD20, CD antigens of LCL cell surface were positive and CD21 was not expressed. 2. Positive and negative HCV RNA strands from cultured cells and supernatants were detected by RT-PCR every month. HCV RNA plus strands persisted in the cultured cells for more than one year. It is interesting that the minus-strand RNA in LCL and the plus-strand RNA in supernatants were observed intermittently and HCV genome type of the LCL was type Ⅱ. 3. Immunohistochemical study found that HCV NS3 and C proteins were mostly expressed in LCL cytoplasm. In situ PCR showed that HCV RNA positive signal was mainly located in LCL cytoplasm. Electronic microscopy found HCV spherical virus-like particles with diameter of approximately 45 to 70nm, some particles were 110nm in LCL cytoplasmic vesicles. Conclusion HCV may exist in LCL cultured cells for a longer period and reproduce in and secrete into the media. It offers a strong evidence for persistence of HCV RNA in PBMC of HCV-infected patients.%目的观察丙型肝炎病人外周血B细胞长期存活状态下其中是否仍有丙型肝炎病毒(HCV)存在,探讨建立HCV体外复制细胞模型的可能性。方法利用EB病毒转化B淋巴细胞技

  18. Immunity of Live Attenuated Japanese Encephalitis(JE)Vaccine to DifferentWild JE Virus Strains%流行性乙型脑炎减毒活疫苗国内外不同野毒株的免疫性

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    目的 研究乙型脑炎减毒活疫苗对国内外不同野毒株的免疫原性。方法 用小鼠保护力试验和空斑减少中和试验检测该疫苗对国内外不同野毒株攻击的保护作用及其免疫血清的中和能力。结果 小鼠免疫1针后均能抵抗国内11株和国外11株乙脑病毒的攻击,保护率均可达90%以上;人体免疫血清对台湾1株和国外9株病毒均有明显的中和作用。结论 SA14-142株乙脑活疫苗具有广谱的免疫原性。%Objective To study on the immunity of live attenuated Japanese Encephalitis(JE)vaccine todifferent wild JE virus strains. Methods The neutralizing effect of the vaccine on different wild JE virusstrains was detected by plaque reduction neutralization test(PRNT), and the immunogenicity of it was studiedin mice by vaccination-challenge protection test. Results The vaccine could protect mice against the challengewith 11 JE vires strains isolated in China and 11 in Thailand,Viemam, Indonesia, India, Phihppines and Ja-pan. The protective rate of it reached above 90%. Human immune sera showed significant neutralizing effect on1 JE virus swain isolated in Taiwan and 9 strains isolated abroad. Conclusion Live attenuated JE vaccine pre-pared with strain SA14-14-2 has broad specmun immunogenicity.

  19. Reciprocal Antibody and Complement Responses of Two Chicken Breeds to Vaccine Strains of Newcastle Disease Virus, Infectious Bursal Disease Virus and Infectious Bronchitis Virus

    NARCIS (Netherlands)

    Baelmans, R.; Parmentier, H.K.; Dorny, P.; Demey, F.; Berkvens, D.

    2006-01-01

    Serum antibody responses and haemolytic complement activity were evaluated in White Leghorn (WLH) and Rhode Island Red (RIR) chickens that were vaccinated with live-attenuated vaccines of Newcastle disease virus, or infectious bronchitis virus, or infectious bursal disease virus by means of ocular c

  20. Progressive adaptation of a Georgian isolate of African swine fever virus to vero cells leads to a gradual attenuation of virulence in swine corresponding to major changes of the viral genome

    Science.gov (United States)

    African swine fever virus (ASFV) causes a contagious and often lethal disease of feral and domestic swine. Experimental vaccines derived from naturally occurring, genetically modified or cell culture-adapted ASFV have been evaluated but no commercial vaccine is available to control African Swine Fev...

  1. Planetary Ices Attenuation Properties

    Science.gov (United States)

    McCarthy, Christine; Castillo-Rogez, Julie C.

    In this chapter, we review the topic of energy dissipation in the context of icy satellites experiencing tidal forcing. We describe the physics of mechanical dissipation, also known as attenuation, in polycrystalline ice and discuss the history of laboratory methods used to measure and understand it. Because many factors - such as microstructure, composition and defect state - can influence rheological behavior, we review what is known about the mechanisms responsible for attenuation in ice and what can be inferred from the properties of rocks, metals and ceramics. Since attenuation measured in the laboratory must be carefully scaled to geologic time and to planetary conditions in order to provide realistic extrapolation, we discuss various mechanical models that have been used, with varying degrees of success, to describe attenuation as a function of forcing frequency and temperature. We review the literature in which these models have been used to describe dissipation in the moons of Jupiter and Saturn. Finally, we address gaps in our present knowledge of planetary ice attenuation and provide suggestions for future inquiry.

  2. Frequency Dependent Attenuation Revisited

    CERN Document Server

    Richard, Kowar; Xavier, Bonnefond

    2009-01-01

    The work is inspired by thermo-and photoacoustic imaging, where recent efforts are devoted to take into account attenuation and varying wave speed parameters. In this paper we study causal equations describing propagation of attenuated pressure waves. We review standard models like frequency power laws and and the thermo-viscous equation. The lack of causality of standard models in the parameter range relevant for photoacoustic imaging requires to derive novel equations. The main ingredients for deriving causal equations are the Kramers-Kronig relation and the mathematical concept of linear system theory. The theoretical results of this work are underpined by numerical experiments.

  3. Viruses, dendritic cells and the lung

    Directory of Open Access Journals (Sweden)

    Graham Barney S

    2001-06-01

    Full Text Available Abstract The interaction between viruses and dendritic cells (DCs is varied and complex. DCs are key elements in the development of a host response to pathogens such as viruses, but viruses have developed survival tactics to either evade or diminish the immune system that functions to kill and eliminate these micro-organisms. In the present review we summarize current concepts regarding the function of DCs in the immune system, our understanding of how viruses alter DC function to attenuate both the virus-specific and global immune response, and how we may be able to exploit DC function to prevent or treat viral infections.

  4. Infections That Pets Carry (For Parents)

    Science.gov (United States)

    ... Your 1- to 2-Year-Old Infections That Pets Carry KidsHealth > For Parents > Infections That Pets Carry ... how to protect your family from infections. How Pets Spread Infections Like people, all animals carry germs . ...

  5. Freeze-drying of live virus vaccines: A review.

    Science.gov (United States)

    Hansen, L J J; Daoussi, R; Vervaet, C; Remon, J-P; De Beer, T R M

    2015-10-13

    Freeze-drying is the preferred method for stabilizing live, attenuated virus vaccines. After decades of research on several aspects of the process like the stabilization and destabilization mechanisms of the live, attenuated viruses during freeze-drying, the optimal formulation components and process settings are still matter of research. The molecular complexity of live, attenuated viruses, the multiple destabilization pathways and the lack of analytical techniques allowing the measurement of physicochemical changes in the antigen's structure during and after freeze-drying mean that they form a particular lyophilization challenge. The purpose of this review is to overview the available information on the development of the freeze-drying process of live, attenuated virus vaccines, herewith focusing on the freezing and drying stresses the viruses can undergo during processing as well as on the mechanisms and strategies (formulation and process) that are used to stabilize them during freeze-drying.

  6. Polymerase Mechanism-Based Method of Viral Attenuation

    Science.gov (United States)

    Lee, Cheri A.; August, Avery; Arnold, Jamie J.; Cameron, Craig E.

    2016-01-01

    Vaccines remain the most effective way of preventing infection and spread of infectious diseases. These prophylactics have been used for centuries but still to this day only three main design strategies exist: (1) live attenuated virus (LAV) vaccines, (2) killed or inactivated virus vaccines, (3) and subunit vaccines of the three, the most efficacious vaccines remain LAVs. LAVs replicate in relevant tissues, elicit strong cellular and humoral responses, and often confer lifelong immunity. While this vaccine strategy has produced the majority of successful vaccines in use today, there are also important safety concerns to consider with this approach. In the past, the development of LAVs has been empirical. Blind passage of viruses in various cell types results in the accumulation of multiple attenuating mutations leaving the molecular mechanisms of attenuation unknown. Also, due to the high error rate of RNA viruses and selective pressures of the host environment, these LAVs, derived from such viruses, can potentially revert back to wild-type virulence. This not only puts the vaccinee at risk, but if shed can put those that are unvaccinated at risk as well. While these vaccines have been successful there still remains a need for a rational design strategy by which to create additional LAVs. One approach for rational vaccine design involves increasing the fidelity of the viral RdRp. Increased fidelity decreases the viral mutational frequency thereby reducing the genetic variation the virus needs in order to evade the host imposed bottlenecks to infection. While polymerase mutants exist which decrease viral mutation frequency the mutations are not in conserved regions of the polymerase, which doesn’t lend itself toward using a common mutant approach toward developing a universal vaccine strategy for all RNA viruses. We have identified a conserved lysine residue in the active site of the PV RdRp that acts as a general acid during nucleotide incorporation. Mutation

  7. Initial characterization of Vaccinia Virus B4 suggests a role in virus spread

    Energy Technology Data Exchange (ETDEWEB)

    Burles, Kristin; Irwin, Chad R.; Burton, Robyn-Lee [Li Ka Shing Institute of Virology, Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada T6G 2S2 (Canada); Schriewer, Jill [Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, St. Louis, MO (United States); Evans, David H. [Li Ka Shing Institute of Virology, Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada T6G 2S2 (Canada); Buller, R. Mark [Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, St. Louis, MO (United States); Barry, Michele, E-mail: michele.barry@ualberta.ca [Li Ka Shing Institute of Virology, Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada T6G 2S2 (Canada)

    2014-05-15

    Currently, little is known about the ankyrin/F-box protein B4. Here, we report that B4R-null viruses exhibited reduced plaque size in tissue culture, and decreased ability to spread, as assessed by multiple-step growth analysis. Electron microscopy indicated that B4R-null viruses still formed mature and extracellular virions; however, there was a slight decrease of virions released into the media following deletion of B4R. Deletion of B4R did not affect the ability of the virus to rearrange actin; however, VACV811, a large vaccinia virus deletion mutant missing 55 open reading frames, had decreased ability to produce actin tails. Using ectromelia virus, a natural mouse pathogen, we demonstrated that virus devoid of EVM154, the B4R homolog, showed decreased spread to organs and was attenuated during infection. This initial characterization suggests that B4 may play a role in virus spread, and that other unidentified mediators of actin tail formation may exist in vaccinia virus. - Highlights: • B4R-null viruses show reduced plaque size, and decreased ability to spread. • B4R-null viruses formed mature and extracellular virions; and rearranged actin. • Virus devoid of EVM154, the B4R homolog, was attenuated during infection. • Initial characterization suggests that B4 may play a role in virus spread. • Unidentified mediators of actin tail formation may exist in vaccinia virus.

  8. Biological Characterization of CVRM2-BAC, A Recombinant CV1988 Virus Containing an REV LTR Insertion

    Science.gov (United States)

    It has been previously reported that avian retroviruses, i.e. avian leukosis virus (ALV) and reticoloendotheliosis virus (REV), integrate in the Marek’s disease virus genome affecting MDV pathogenicity. RM-2 is an attenuated serotype 1 MDV virus generated by insertion of the REV LTR in the genome of...

  9. A Brief Analysis of Sister Carrie's Character

    Science.gov (United States)

    Yu, Hanying

    2010-01-01

    Carrie is always dreaming while the rocking chair is rocking again and again, this is the deep impression on us after we read "Sister Carrie" which is the first novel of Theodore Dreiser. In this novel the protagonist Sister Carrie is a controversial person. This paper tries to analyze the character of Sister Carrie in order to find out…

  10. 含临床病毒株聚合酶逆转录酶区的乙肝病毒DNA稳定复制细胞系的构建%Establishment of a Stable Cell Line Replicating Hepatitis B Virus DNA Carrying the Reverse Transcriptase Region Derived from a Clinical Isolate

    Institute of Scientific and Technical Information of China (English)

    向明确; 蔡雪飞; 张文露; 黄爱龙; 胡接力

    2013-01-01

    目的 构建含有临床病毒株聚合酶逆转录酶(RT)区的乙肝病毒(HBV) DNA稳定复制细胞系.方法 采用巢式PCR从患者血清扩增HBV DNA片段,利用片段置换反应将该片段克隆到HBV DNA复制载体,并在该载体上引入新霉素抗性基因,在确认该重组DNA体外可复制后,将其转染HepG2细胞,G418筛选,采用real-time PCR结合ELISA及Southern blot检测初筛和鉴定HBV DNA稳定复制细胞系.结果 从患者血清扩增出的HBV DNA片段nt55~1654被成功置换到HBV复制质粒pLL相应区域,得到质粒p11;新霉素抗性基因表达片段被克隆到p11中HBV DNA下游,获得质粒p11-neo,Southern blot检测证实p11-neo可支持体外复制;p11-neo转染HepG2后,经筛选鉴定,获得了可支持HBV DNA稳定复制的细胞系3-10.结论 建立了含有临床病毒株聚合酶RT区的HBV DNA稳定复制细胞系,real-time PCR结合ELISA有助于HBV DNA稳定复制细胞系的快速初筛鉴定.%Objective To establish a stable cell line that can replicate hepatitis B virus (HBV) DNA carrying the reverse transcriptase sequence derived from a clinical isolate. Methods Nested PCR was used to amplify the HBV DNA fragment from the serum. The fragment was cloned into a plasmid that can support HBV replication in vitro by fragment substitution reaction ( FSR) , followed by the cloning of the neomycin expressing fragment downstream from HBV DNA. G418 selection was conducted after the transfection of HepG2 cells with the recombinant DNA. Real-time PCR and enzyme linked immunosorbent assay (ELISA) were used to screen stable cell lines that can replicate HBV DNA, and the replication of HBV DNA by the cell line was confirmed by using Southern blot analysis. Results Fragment nt55-1654 amplified from the serum DNA was substituted to the plasmid pLL, generating the plasmid p11. The neomycin fragment was cloned into p11 , leading to the plasmid pll-neo, and pll-neo was confirmed to be HBV-replication-competent. A stable

  11. Establishment of Master Cell Stock and Working Cell Bank of MDCK Lines and Selection and Evaluation of the Lines as Candidate Viral Substrates for Approval Production of Combinational Canine Attenuated-live Virus Vaccines

    Institute of Scientific and Technical Information of China (English)

    ZHANG De-li; FANG Fu-de; LI Liu-jin; XIA Geng-tian; HE Xu-yu; GAO Bu-xian; BAI Xiao-hong; HUANG Gao-sheng; LIU Shang-gao; YEN Lung-fei

    2002-01-01

    Under the prerequisite that the incidence of cancer or tumor in negative-control nude mice inoculated subcutaneously with primary feline or canine kidney cell cultures purified in vitro at passage 3 was 0(0/22) and 0 (0/10), respectively. The incidence of the progressively-growing malignant tumor(MT) in positive-control nude mice inoculated subcutaneously with Hela cell cultures of KB, X, or NM20/X strain was 10/10, 25/25 and 5/51, respectively. The results showed that the incidence of tumor in nude mice with di-and hyperploid YB strain of MDCK cell during 17 - 23 passages, with hyper- and hypoploid KA strain of MDCK cell during 6 - 8 passages, with hypoploid WB strain of MDCK cell on passage 6, with hyper-and hypopioid H strain of MDCK cell during 8 - 24 passages was 2/24, 6/10, 5/10 and 10/15, respectively. The chromosomal analysis results showed that the ratio of difference in the rate of modal chromosome number between high(mcs + n) and lowest (mcs)passages was not more than 5- 15% and the structure aberrations was generally 0-3%. These results proved that the genetic characteristics of chromosomal number of cell lines determines their tumorigenicity, but it is species-specific. MDCK line has tumorigenicity no matter what its chromosome karyotype is, at least it has very low tumorigenicity even when its modal chromosome number is hypoploid. It is thus evident that MDCK cell of WB or H strain can be approved as substrate for the preparation of attenuated viral vaccines, but MDCK cell of YB or KA strain can not be approved as substrate for the preparation of attenuated viral vaccines.

  12. Modified vaccinia virus Ankara protects macaques against respiratory challenge with monkeypox virus.

    NARCIS (Netherlands)

    K.J. Stittelaar (Koert); G. van Amerongen (Geert); I. Kondova (Ivanela); R.F. van Lavieren (Rob); F.H. Pistoor (Frank); H.G.M. Niesters (Bert); G.J.J. van Doornum (Gerard); B.A.M. van der Zeijst (Ben); L. Mateo (Luis); P.J. Chaplin (Paul); A.D.M.E. Osterhaus (Albert); T. Kuiken (Thijs)

    2005-01-01

    textabstractThe use of classical smallpox vaccines based on vaccinia virus (VV) is associated with severe complications in both naive and immune individuals. Modified vaccinia virus Ankara (MVA), a highly attenuated replication-deficient strain of VV, has been proven to be safe in humans and immunoc

  13. Modified vaccinia virus Ankara protects macaques against respiratory challenge with monkeypox virus

    NARCIS (Netherlands)

    Stittelaar, Koert J; van Amerongen, Geert; Kondova, Ivanela; Kuiken, Thijs; van Lavieren, Rob F; Pistoor, Frank H M; Niesters, Hubert G M; van Doornum, Gerard; van der Zeijst, Ben A M; Mateo, Luis; Chaplin, Paul J; Osterhaus, Albert D M E

    2005-01-01

    The use of classical smallpox vaccines based on vaccinia virus (VV) is associated with severe complications in both naive and immune individuals. Modified vaccinia virus Ankara (MVA), a highly attenuated replication-deficient strain of VV, has been proven to be safe in humans and immunocompromised a

  14. Insertion of a Reticuloendotheliosis virus LTR into the Marek's disease virus genome

    Science.gov (United States)

    Marek’s disease virus (MDV) had previously been co-cultivated in culture with Reticuloendotheliosis virus (REV). During co-cultivation, a long terminal repeat (LTR) from REV was inserted into the MDV genome. The resulting MDV, designated RM1, was attenuated but still induced severe thymic and bursal...

  15. Human Influenza Virus Infections.

    Science.gov (United States)

    Peteranderl, Christin; Herold, Susanne; Schmoldt, Carole

    2016-08-01

    Seasonal and pandemic influenza are the two faces of respiratory infections caused by influenza viruses in humans. As seasonal influenza occurs on an annual basis, the circulating virus strains are closely monitored and a yearly updated vaccination is provided, especially to identified risk populations. Nonetheless, influenza virus infection may result in pneumonia and acute respiratory failure, frequently complicated by bacterial coinfection. Pandemics are, in contrary, unexpected rare events related to the emergence of a reassorted human-pathogenic influenza A virus (IAV) strains that often causes increased morbidity and spreads extremely rapidly in the immunologically naive human population, with huge clinical and economic impact. Accordingly, particular efforts are made to advance our knowledge on the disease biology and pathology and recent studies have brought new insights into IAV adaptation mechanisms to the human host, as well as into the key players in disease pathogenesis on the host side. Current antiviral strategies are only efficient at the early stages of the disease and are challenged by the genomic instability of the virus, highlighting the need for novel antiviral therapies targeting the pulmonary host response to improve viral clearance, reduce the risk of bacterial coinfection, and prevent or attenuate acute lung injury. This review article summarizes our current knowledge on the molecular basis of influenza infection and disease progression, the key players in pathogenesis driving severe disease and progression to lung failure, as well as available and envisioned prevention and treatment strategies against influenza virus infection.

  16. Ultrasonic attenuation in pearlitic steel.

    Science.gov (United States)

    Du, Hualong; Turner, Joseph A

    2014-03-01

    Expressions for the attenuation coefficients of longitudinal and transverse ultrasonic waves are developed for steel with pearlitic microstructure. This type of lamellar duplex microstructure influences attenuation because of the lamellar spacing. In addition, longitudinal attenuation measurements were conducted using an unfocused transducer with 10 MHz central frequency on the cross section of a quenched railroad wheel sample. The dependence of longitudinal attenuation on the pearlite microstructure is observed from the changes of longitudinal attenuation from the quenched tread surface to deeper locations. The results show that the attenuation value is lowest and relatively constant within the quench depth, then increases linearly. The experimental results demonstrate a reasonable agreement with results from the theoretical model. Ultrasonic attenuation provides an important non-destructive method to evaluate duplex microstructure within grains which can be implemented for quality control in conjunction with other manufacturing processes.

  17. Smaller Fleas: Viruses of Microorganisms

    OpenAIRE

    Paul Hyman; Stephen T. Abedon

    2012-01-01

    Life forms can be roughly differentiated into those that are microscopic versus those that are not as well as those that are multicellular and those that, instead, are unicellular. Cellular organisms seem generally able to host viruses, and this propensity carries over to those that are both microscopic and less than truly multicellular. These viruses of microorganisms, or VoMs, in fact exist as the world’s most abundant somewhat autonomous genetic entities and include the viruses of domain B...

  18. A FEMINIST READING OF SISTER CARRIE

    Institute of Scientific and Technical Information of China (English)

    高陈科

    2011-01-01

    In the history of American literature, Sister Carrie has always been a controversial character. The critics regard Carrie either as a "fallen woman" or as a "new women". This thesis aims to offer a feminist reading of the image of Sister Carrie in the con

  19. 25 CFR 167.6 - Carrying capacities.

    Science.gov (United States)

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Carrying capacities. 167.6 Section 167.6 Indians BUREAU... Carrying capacities. (a) The Commissioner of Indian Affairs on June 26, 1943, promulgated the authorized carrying capacity for each land management district of the Navajo Reservation. (b) Recommended...

  20. 7 CFR 1437.402 - Carrying capacity.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Carrying capacity. 1437.402 Section 1437.402... Determining Coverage of Forage Intended for Animal Consumption § 1437.402 Carrying capacity. (a) CCC will establish a carrying capacity for all grazed forage present in the county for purposes of administering...

  1. A novel live-attenuated vaccine candidate for mayaro Fever.

    Directory of Open Access Journals (Sweden)

    William J Weise

    2014-08-01

    Full Text Available Mayaro virus (MAYV is an emerging, mosquito-borne alphavirus that causes a dengue-like illness in many regions of South America, and which has the potential to urbanize. Because no specific treatment or vaccine is available for MAYV infection, we capitalized on an IRES-based approach to develop a live-attenuated MAYV vaccine candidate. Testing in infant, immunocompetent as well as interferon receptor-deficient mice demonstrated a high degree of attenuation, strong induction of neutralizing antibodies, and efficacy against lethal challenge. This vaccine strain was also unable to infect mosquito cells, a major safety feature for a live vaccine derived from a mosquito-borne virus. Further preclinical development of this vaccine candidate is warranted to protect against this important emerging disease.

  2. A novel live-attenuated vaccine candidate for mayaro Fever.

    Science.gov (United States)

    Weise, William J; Hermance, Meghan E; Forrester, Naomi; Adams, A Paige; Langsjoen, Rose; Gorchakov, Rodion; Wang, Eryu; Alcorn, Maria D H; Tsetsarkin, Konstantin; Weaver, Scott C

    2014-08-01

    Mayaro virus (MAYV) is an emerging, mosquito-borne alphavirus that causes a dengue-like illness in many regions of South America, and which has the potential to urbanize. Because no specific treatment or vaccine is available for MAYV infection, we capitalized on an IRES-based approach to develop a live-attenuated MAYV vaccine candidate. Testing in infant, immunocompetent as well as interferon receptor-deficient mice demonstrated a high degree of attenuation, strong induction of neutralizing antibodies, and efficacy against lethal challenge. This vaccine strain was also unable to infect mosquito cells, a major safety feature for a live vaccine derived from a mosquito-borne virus. Further preclinical development of this vaccine candidate is warranted to protect against this important emerging disease.

  3. ECHO virus

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/001340.htm ECHO virus To use the sharing features on this page, please enable JavaScript. Enteric cytopathic human orphan (ECHO) viruses are a group of viruses that lead to ...

  4. Proteção fetal frente a desafio com o vírus da Diarréia Viral Bovina (BVDV em ovelhas imunizadas com duas amostras de vírus modificadas experimentalmente Fetal protection against challenge with bovine viral diarrhea virus (BVDV in pregnant ewes immunized with two strains experimentally attenuated

    Directory of Open Access Journals (Sweden)

    Mário C.S. Brum

    2002-04-01

    virus (BVDV submitted to multiple passages in tissue culture associated with ultraviolet irradiation were evaluated as vaccine virus candidates. The attenuation of the modified viruses was assessed in calves and in pregnant ewes. Intramuscular inoculation of the viruses in four seronegative calves produced only a mild and transient rise in body temperature, followed by the production of high titers of neutralizing antibodies. The viruses were not detected in nasal secretions or in the blood following inoculation. However, intramuscular inoculation of these viruses in four pregnant ewes resulted in transplacental transmission and infection of all fetuses. To assess fetal protection conferred by immunization, pregnant ewes immunized twice with the modified viruses were subsequently challenged by intranasal inoculation of BVDV-1 (SV-126.8, n=6 or BVDV-2 (SV-260, n=5. At the day of challenge (134 days after the second immunization, all ewes had high titers of neutralizing antibodies (256 to >4096 to the vaccine viruses and variable titers (8 to >4096 to Brazilian BVDV-1 and BVDV-2 field isolates. Fifteen days after challenge, the ewes were euthanized and fetal tissues were examined for infectivity. All fetuses from non-vaccinated, challenged ewes (n=4 were infected. In contrast, none of the fetuses from the immunized dams (n=11 were positive for virus, indicating that the immunological response induced by immunization with the vaccine candidate viruses was capable of preventing fetal infection. These results indicate that it is possible to achieve fetal protection to BVDV by induction of a strong immunological response using modified live vaccines.

  5. MODELING LEACHING OF VIRUSES BY THE MONTE CARLO METHOD

    Science.gov (United States)

    A predictive screening model was developed for fate and transport of viruses in the unsaturated zone. A database of input parameters allowed Monte Carlo analysis with the model. The resulting kernel densities of predicted attenuation during percolation indicated very ...

  6. Herpes zoster caused by vaccine-strain varicella zoster virus in an immunocompetent recipient of zoster vaccine.

    Science.gov (United States)

    Tseng, Hung Fu; Schmid, D Scott; Harpaz, Rafael; LaRussa, Philip; Jensen, Nancy J; Rivailler, Pierre; Radford, Kay; Folster, Jennifer; Jacobsen, Steven J

    2014-04-01

    We report the first laboratory-documented case of herpes zoster caused by the attenuated varicella zoster virus (VZV) contained in Zostavax in a 68-year-old immunocompetent adult with strong evidence of prior wild-type VZV infection. The complete genome sequence of the isolate revealed that the strain carried 15 of 42 (36%) recognized varicella vaccine-associated single-nucleotide polymorphisms, including all 5 of the fixed vaccine markers present in nearly all of the strains in the vaccine. The case of herpes zoster was relatively mild and resolved without complications.

  7. Sister Carrie:A Material Pursuer

    Institute of Scientific and Technical Information of China (English)

    马春花

    2015-01-01

    Sister Carrie dramatized by Dreiser is totally a material pursuer. She is selfish and accumulates money in a crazy way. What she does inevitably centers on materials. Living with Drouet and later Hurstwood, Carrie gets what she wants and enjoys the luxurious life in an easy way. However, with the satisfaction of some of her desires, Carrie ’s desires grow and expand. With enough food and clothes, she needs luxury. Hurstwood’s failure in business leads Carrie to the stage and finally she makes a suc⁃cess and becomes a famous actress in Broadway. She gets more money, but her desires grow even higher. Nothing can satisfy her. In this essay, the author tries to analyze Carrie according to Freud’s and Guo Weilu’s theories and prove that Carrie is totally a material pursuer.

  8. The Attenuated Live Yellow Fever Virus 17D Infects the Thymus and Induces Thymic Transcriptional Modifications of Immunomodulatory Genes in C57BL/6 and BALB/C Mice

    Directory of Open Access Journals (Sweden)

    Breno Luiz Melo-Lima

    2015-01-01

    Full Text Available Thymus is involved in induction of self-tolerance in T lymphocytes, particularly due to Aire activity. In peripheral tissues, Treg cells and immunomodulatory molecules, like the major histocompatibility complex (MHC class Ib molecules, are essential for maintenance of autotolerance during immune responses. Viral infections can trigger autoimmunity and modify thymic function, and YFV17D immunization has been associated with the onset of autoimmunity, being contraindicated in patients with thymic disorders. Aiming to study the influence of YFV17D immunization on the transcriptional profiles of immunomodulatory genes in thymus, we evaluated the gene expression of AIRE, FOXP3, H2-Q7 (Qa-2/HLA-G, H2-T23 (Qa-1/HLA-E, H2-Q10, and H2-K1 following immunization with 10,000 LD50 of YFV17D in C57BL/6 and BALB/c mice. The YFV17D virus replicated in thymus and induced the expression of H2-Q7 (Qa-2/HLA-G and H2-T23 (Qa-1/HLA-E transcripts and repressed the expression of AIRE and FOXP3. Transcriptional expression varied according to tissue and mouse strain analyzed. Expression of H2-T23 (Qa-1/HLA-E and FOXP3 was induced in thymus and liver of C57BL/6 mice, which exhibited defective control of viral load, suggesting a higher susceptibility to YFV17D infection. Since the immunization with YFV17D modulated thymus gene expression in genetically predisposed individuals, the vaccine may be related to the onset of autoimmunity disorders.

  9. ENVIRONMENTAL CARRYING CAPACITY BASED ON SPATIAL PLANNING

    OpenAIRE

    Luthfi Muta'ali

    2013-01-01

    The aims of this research were to examine environmental carrying capacity analyzed based on aspects of spatial planning and eco-region. The result showed that Kulonprogo Regency has low value of environmental carrying capacity and can only support as much as 79.81% of its total population. Analysis of variance showed significant difference of environmental carrying capacity of protected and cultivated area. The main factor among 12 variables determining the degree of environmen...

  10. Carrie Chapman Catt and Woman Suffrage.

    Science.gov (United States)

    Hardesty, Carolyn, Ed.

    1989-01-01

    Most of the material for this issue of the "Goldfinch," which explores the life of Carrie Chapman Catt, came from the archives of the State Historical Society of Iowa. Carrie Chapman Catt (1859-1947) was an Iowan who advocated woman suffrage and spent 26 years actively working for that cause. The issue contains a biography of Catt, and…

  11. Bivalve carrying capacity in coastal ecosystems

    NARCIS (Netherlands)

    Dame, R.F.; Prins, T.C.

    1998-01-01

    carrying capacity of suspension feeding bivalves in 11 coastal and estuarine ecosystems is examined. Bivalve carrying capacity is defined in terms of water mass residence time, primary production time and bivalve clearance time. Turnover times for the 11 ecosystems are compared both two and three di

  12. Comments on the image of Sister Carrie

    Institute of Scientific and Technical Information of China (English)

    张楠

    2016-01-01

    Thedore Oreiser was one of America's greatest writers and one of his famous masterpieces is Sister Carrie. the heroin of the novel was a country girl who struggled for success and finally became a movie star. Analysis on the image of Carrie is of practical significance to the country girls swarming into the city nowdays in our country.

  13. Parallelization of Reversible Ripple-carry Adders

    DEFF Research Database (Denmark)

    Thomsen, Michael Kirkedal; Axelsen, Holger Bock

    2009-01-01

    wherein $m$ parallel $k$-bit reversible ripple-carry adders are combined to form a reversible $mk$-bit \\emph{ripple-block carry adder} with logic depth $\\mathcal{O}(m+k)$ for a \\emph{minimal} logic depth $\\mathcal{O}(\\sqrt{mk})$, thus improving on the $mk$-bit ripple-carry adder logic depth $\\mathcal......{O}(m\\cdot k)$. The underlying mechanisms of the parallelization scheme are formally proven correct. We also show designs for garbage-less reversible comparison circuits. We compare the circuit costs of the resulting ripple-block carry adder with known optimized reversible ripple-carry adders in measures...... of circuit delay, width, gate, transistor count, and relative power efficiency, and find that the parallelized adder offers significant speedups at realistic word sizes with modest parallelization overhead....

  14. Sister Carrie, an Adherent of Desires

    Institute of Scientific and Technical Information of China (English)

    裴水妹

    2007-01-01

    Sister Carrie is one of the most controversial characters in American literature.Thought as a "fallen woman" firstly,she was defined as a "new woman" by some critics later. However, by digging into the motivaton behind the whole process of Carrie's "success", the relationship between Carrie and her creator (the author), the social conditions of then American, it can be found that Carrie has never been free-standing on her thought and she has never found her real-sdf even after becoming a famous actress. In a society dominated by mass consumerism Carrie is only an adherent of her own desires. She also is a representative of all those country girls flooded into cities, a symbol and a sacrifice of the urbanization of America in a time countryside was overcome by cities.

  15. Envelope exchange for the generation of live-attenuated arenavirus vaccines.

    Directory of Open Access Journals (Sweden)

    Andreas Bergthaler

    2006-06-01

    Full Text Available Arenaviruses such as Lassa fever virus cause significant mortality in endemic areas and represent potential bioterrorist weapons. The occurrence of arenaviral hemorrhagic fevers is largely confined to Third World countries with a limited medical infrastructure, and therefore live-attenuated vaccines have long been sought as a method of choice for prevention. Yet their rational design and engineering have been thwarted by technical limitations. In addition, viral genes had not been identified that are needed to cause disease but can be deleted or substituted to generate live-attenuated vaccine strains. Lymphocytic choriomeningitis virus, the prototype arenavirus, induces cell-mediated immunity against Lassa fever virus, but its safety for humans is unclear and untested. Using this virus model, we have developed the necessary methodology to efficiently modify arenavirus genomes and have exploited these techniques to identify an arenaviral Achilles' heel suitable for targeting in vaccine design. Reverse genetic exchange of the viral glycoprotein for foreign glycoproteins created attenuated vaccine strains that remained viable although unable to cause disease in infected mice. This phenotype remained stable even after extensive propagation in immunodeficient hosts. Nevertheless, the engineered viruses induced T cell-mediated immunity protecting against overwhelming systemic infection and severe liver disease upon wild-type virus challenge. Protection was established within 3 to 7 d after immunization and lasted for approximately 300 d. The identification of an arenaviral Achilles' heel demonstrates that the reverse genetic engineering of live-attenuated arenavirus vaccines is feasible. Moreover, our findings offer lymphocytic choriomeningitis virus or other arenaviruses expressing foreign glycoproteins as promising live-attenuated arenavirus vaccine candidates.

  16. Envelope Exchange for the Generation of Live-Attenuated Arenavirus Vaccines.

    Directory of Open Access Journals (Sweden)

    2006-06-01

    Full Text Available Arenaviruses such as Lassa fever virus cause significant mortality in endemic areas and represent potential bioterrorist weapons. The occurrence of arenaviral hemorrhagic fevers is largely confined to Third World countries with a limited medical infrastructure, and therefore live-attenuated vaccines have long been sought as a method of choice for prevention. Yet their rational design and engineering have been thwarted by technical limitations. In addition, viral genes had not been identified that are needed to cause disease but can be deleted or substituted to generate live-attenuated vaccine strains. Lymphocytic choriomeningitis virus, the prototype arenavirus, induces cell-mediated immunity against Lassa fever virus, but its safety for humans is unclear and untested. Using this virus model, we have developed the necessary methodology to efficiently modify arenavirus genomes and have exploited these techniques to identify an arenaviral Achilles' heel suitable for targeting in vaccine design. Reverse genetic exchange of the viral glycoprotein for foreign glycoproteins created attenuated vaccine strains that remained viable although unable to cause disease in infected mice. This phenotype remained stable even after extensive propagation in immunodeficient hosts. Nevertheless, the engineered viruses induced T cell-mediated immunity protecting against overwhelming systemic infection and severe liver disease upon wild-type virus challenge. Protection was established within 3 to 7 d after immunization and lasted for approximately 300 d. The identification of an arenaviral Achilles' heel demonstrates that the reverse genetic engineering of live-attenuated arenavirus vaccines is feasible. Moreover, our findings offer lymphocytic choriomeningitis virus or other arenaviruses expressing foreign glycoproteins as promising live-attenuated arenavirus vaccine candidates.

  17. Viruses of the Archaea

    DEFF Research Database (Denmark)

    Basta, T.; Garrett, Roger Antony; Prangishvili,, David

    2009-01-01

    Double-stranded deoxyribonucleic acid (DNA) viruses that infect members of the third domain of life, the Archaea, are diverse and exceptional in both their morphotypes and their genomic properties. The majority of characterized species infect hyperthermophilic hosts and carry morphological featur...

  18. Effects of myxoma virus and rabbit hemorrhagic disease virus on the physiological condition of wild European rabbits: Is blood biochemistry a useful monitoring tool?

    Science.gov (United States)

    Pacios-Palma, Isabel; Santoro, Simone; Bertó-Moran, Alejandro; Moreno, Sacramento; Rouco, Carlos

    2016-12-01

    Myxomatosis and rabbit hemorrhagic disease (RHD) are the major viral diseases that affect the wild European rabbit (Oryctolagus cuniculus). These diseases arrived in Europe within the last decades and have caused wild rabbit populations to decline dramatically. Both viruses are currently considered to be endemic in the Iberian Peninsula; periodic outbreaks that strongly impact wild populations regularly occur. Myxoma virus (MV) and rabbit hemorrhagic disease virus (RHDV) alter the physiology of infected rabbits, resulting in physical deterioration. Consequently, the persistence and viability of natural populations are affected. The main goal of our study was to determine if blood biochemistry is correlated with serostatus in wild European rabbits. We carried out seven live-trapping sessions in three wild rabbit populations over a two-year period. Blood samples were collected to measure anti-MV and anti-RHDV antibody concentrations and to measure biochemical parameters related to organ function, protein metabolism, and nutritional status. Overall, we found no significant relationships between rabbit serostatus and biochemistry. Our main result was that rabbits that were seropositive for both MV and RHDV had low gamma glutamyltransferase concentrations. Given the robustness of our analyses, the lack of significant relationships may indicate that the biochemical parameters measured are poor proxies for serostatus. Another explanation is that wild rabbits might be producing attenuated physiological responses to these viruses because the latter are now enzootic in the study area.

  19. Gun Carrying by High School Students in Boston, MA: Does Overestimation of Peer Gun Carrying Matter?

    Science.gov (United States)

    Hemenway, David; Vriniotis, Mary; Johnson, Renee M.; Miller, Matthew; Azrael, Deborah

    2011-01-01

    This paper investigates: (1) whether high school students overestimate gun carrying by their peers, and (2) whether those students who overestimate peer gun carrying are more likely to carry firearms. Data come from a randomly sampled survey conducted in 2008 of over 1700 high school students in Boston, MA. Over 5% of students reported carrying a…

  20. Carry Select Adder Circuit with A Successively Incremented Carry Number Block

    OpenAIRE

    Deepak; Bal Krishan

    2014-01-01

    This paper reports a conditional carry select (CCS) adder circuit with a successively-incremented-carry-number block (SICNB) structure for low-voltage VLSI implementation. Owing to the successively-incremented-carry-number block (SICNB) structure, the new 16-bit SICNB CCS adder provides a 37% faster speed as compared to the conventional conditional Carry select adder based on the SPICE results

  1. Prospects for development of African swine fever virus vaccines.

    Science.gov (United States)

    Dixon, L K; Abrams, C C; Chapman, D D G; Goatley, L C; Netherton, C L; Taylor, G; Takamatsu, H H

    2013-01-01

    African swine fever virus is a large DNA virus which can cause an acute haemorrhagic fever in pigs resulting in high mortality. No vaccine is available, limiting options for control. The virus encodes up to 165 genes and virus particles are multi-layered and contain more than 50 proteins. Pigs immunised with natural low virulence isolates or attenuated viruses produced by passage in tissue culture and by targeted gene deletions can be protected against challenge with virulent viruses. CD8+ cells are required for protection induced by attenuated strain OURT88/3. Passive transfer of antibodies from immune to naïve pigs can also induce protection. Knowledge of the genome sequences of attenuated and virulent strains and targeted gene deletions from virulent strains have identified a number of virus genes involved in virulence and immune evasion. This information can be used to produce rationally attenuated vaccine strains. Virus antigens that are targets for neutralising antibodies have been identified and immunisation with these recombinant proteins has been shown to induce partial protection. However knowledge of antigens which encode the dominant protective epitopes recognised by CD8+ T cells is lacking.

  2. Immunogenicity and protective efficacy of a live attenuated H5N1 vaccine in nonhuman primates.

    Directory of Open Access Journals (Sweden)

    Shufang Fan

    2009-05-01

    Full Text Available The continued spread of highly pathogenic H5N1 influenza viruses among poultry and wild birds, together with the emergence of drug-resistant variants and the possibility of human-to-human transmission, has spurred attempts to develop an effective vaccine. Inactivated subvirion or whole-virion H5N1 vaccines have shown promising immunogenicity in clinical trials, but their ability to elicit protective immunity in unprimed human populations remains unknown. A cold-adapted, live attenuated vaccine with the hemagglutinin (HA and neuraminidase (NA genes of an H5N1 virus A/VN/1203/2004 (clade 1 was protective against the pulmonary replication of homologous and heterologous wild-type H5N1 viruses in mice and ferrets. In this study, we used reverse genetics to produce a cold-adapted, live attenuated H5N1 vaccine (AH/AAca that contains HA and NA genes from a recent H5N1 isolate, A/Anhui/2/05 virus (AH/05 (clade 2.3, and the backbone of the cold-adapted influenza H2N2 A/AnnArbor/6/60 virus (AAca. AH/AAca was attenuated in chickens, mice, and monkeys, and it induced robust neutralizing antibody responses as well as HA-specific CD4+ T cell immune responses in rhesus macaques immunized twice intranasally. Importantly, the vaccinated macaques were fully protected from challenge with either the homologous AH/05 virus or a heterologous H5N1 virus, A/bar-headed goose/Qinghai/3/05 (BHG/05; clade 2.2. These results demonstrate for the first time that a cold-adapted H5N1 vaccine can elicit protective immunity against highly pathogenic H5N1 virus infection in a nonhuman primate model and provide a compelling argument for further testing of double immunization with live attenuated H5N1 vaccines in human trials.

  3. VIIRSN Level-3 Standard Mapped Image, Diffuse Attenuation K490, Monthly, 4km

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NASA distributes Diffuse Attenuation Coefficient at 490 nm Wavelength data from the NPP-Suomi satellite. Measurements are gathered by the VIIRS instrument carried...

  4. VIIRSN Level-3 Standard Mapped Image, Diffuse Attenuation K490, 8 Day, 4km

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NASA distributes Diffuse Attenuation Coefficient at 490 nm Wavelength data from the NPP-Suomi satellite. Measurements are gathered by the VIIRS instrument carried...

  5. Effects of carrying methods and box handles on two-person team carrying capacity for females.

    Science.gov (United States)

    Wu, Swei-Pi; Chang, Shu-Yu

    2010-07-01

    This study used a psychophysical approach to examine the effects of carrying methods and the presence or absence of box handles on the maximum acceptable weight carried and resulting responses (heart rate and rating of perceived exertion) in a two-person carrying task. After training, 16 female subjects performed a two-person carrying task at knuckle height for an 8-h work period. Each subject performed 4 different carrying combinations two times. The independent variables were carrying methods (parallel and tandem walking) and box handles (with and without handles). For comparison with two-person carrying, the subjects also performed one-person carrying. The results showed that the maximum acceptable weight carried (MAWC), heart rate (HR), and rating of perceived exertion (RPE) were significantly affected by the presence of box handles. However, the subjects' MAWC, HR, and RPE values were not significantly influenced by the carrying methods. The test-retest reliability of the psychophysical approach was 0.945. The carrying efficiency of two-person carrying was 96.2% of the one-person carrying method. In general, the use of box with handles allows the subjects to carry a higher MAWC (with lower HR and RPE) compared to carrying boxes without handles.

  6. Protective efficacy of a recombinant BAC clone of Marek's disease virus containing REV-LTR

    Science.gov (United States)

    Insertion of reticuloendotheliosis virus (REV) long-terminal repeat (LTR) into a bacterial artificial chromosome (BAC) clone of a very virulent strain of Marek’s disease (MD) virus (MDV), Md5 (Kim et al, 2011) rendered the resultant recombinant virus termed rMd5 REV-LTR BAC fully attenuated at passa...

  7. A Naturalistic Reading of Sister Carrie

    Institute of Scientific and Technical Information of China (English)

    谈月

    2016-01-01

    Sister Carrie is well known as the works in which naturalism attained maturity in America. Up until now, the relevant research on Dreiser and his Sister Carrie abroad and at home is primarily concerned with the frustration of American dream, the naturalistic thoughts and pessimism. The paper attempts to study it from naturalistic point of view and explain how environmental, hereditary factors and the idea of“survival of the fittest”influence Carrie’s fate.

  8. Attenuated vesicular stomatitis virus induces apoptosis in cervical cancer HeLa cells and its mechanism%减毒水泡性口炎病毒诱导宫颈癌HeLa细胞的凋亡及其作用机制

    Institute of Scientific and Technical Information of China (English)

    连海; 张静敏; 夏志平; 汤晶; 张爽; 于玲

    2011-01-01

    Objective: To investigate the apoptosis-inducing effect of an attenuated vesicular stomatitis virus in cervical cancer HeLa cells, and to explore the possible mechanism. Methods: HeLa cells were infected with VSV ( MOI = 1.0) and the cell proliferation was determined by MTT assay at 6, 12, 18, 24, and 30 h after infection. Morphological changes of apoptosis were observed by acridine orange (AO)/ethidium bromide (EB) staining. Annexin V/PI double-staining was performed to detect early apoptosis rate of HeLa cells and the sub-G1 apoptotic peak was examined by flow cytometry. The mitochondrial membrane potential of HeLa cells was measured by the JC-1 staining. The activities of caspase-9, -8 and -3 were measured by caspase assay kit. Results: After HeLa cells were exposed to attenuated VSV for 12 h and 24 h, the viabilities of cells were reduced to (78.4 ± 1.9 ) % and (63.1 ± 5.6 ) % ( P < 0.01 ); the early apoptosis rates were 16.88±2.48)% and (31.9 ±4.24)% (P<0.01); the Sub-G1 apoptotic peaks were (14.85 ±1.48)% and 21.05 ± 2. 28) % (P < 0.01 ), respectively. Attenuated VSV significantly decreased mitochondrial membrane potential in HeLa cells with the increase of infection time ( P < 0.05 ). The activities of caspase-9 and caspase-3 of HeLa cells were significantly increased after VSV infection ( all P < 0.05 ). Conclusion: The attenuated VSV can inhibit the proliferation of HeLa cells and trigger apoptosis via caspase-9 and caspase-3-dependent pathway.%目的:研究减毒水泡性口炎病毒(vesicular stomatitis virus,VSV)对宫颈癌HeLa细胞的凋亡诱导作用,并探讨其可能的机制.方法:将减毒VSV以1.0 MOl的接种密度感染HeLa细胞,在6、12、18、24和30 h后收集细胞,MTT法检测HeLa细胞的增殖;AO/EB染色观察HeLa细胞凋亡形态学变化,Annexin V-FITC/PI双染法检测HeLa细胞早期凋亡率,流式细胞术分析HeLa细胞sub-G1凋亡峰,JC-1染色法测定细胞线粒体跨膜电位水

  9. Immunization with a live attenuated H7N9 influenza vaccine protects mice against lethal challenge.

    Directory of Open Access Journals (Sweden)

    Xiaolan Yang

    Full Text Available The emergence of severe cases of human influenza A (H7N9 viral infection in China in the spring of 2003 resulted in a global effort to rapidly develop an effective candidate vaccine. In this study, a cold-adapted (ca, live attenuated monovalent reassortant influenza H7N9 virus (Ah01/AA ca was generated using reverse genetics that contained hemagglutinin (HA and neuraminidase (NA genes from a 2013 pandemic A H7N9 isolate, A/Anhui/01/2013 virus (Ah01/H7N9; the remaining six backbone genes derived from the cold-adapted influenza H2N2 A/Ann Arbor/6/60 virus (AA virus. Ah01/AA ca virus exhibited temperature sensitivity (ts, ca, and attenuation (att phenotypes. Intranasal immunization of female BALB/c mice with Ah01/AA ca twice at a 2-week interval induced robust humoral, mucosal, and cell-mediated immune responses in a dose-dependent manner. Furthermore, the candidate Ah01/AA ca virus was immunogenic and offered partial or complete protection of mice against a lethal challenge by the live 2013 influenza A H7N9 (A/Anhui/01/2013. Protection was demonstrated by the inhibition of viral replication and the attenuation of histopathological changes in the challenged mouse lung. Taken together, these data support the further evaluation of this Ah01/AA ca candidate vaccine in primates.

  10. Effects of box handle position and carrying range on bi-manual carrying capacity for females.

    Science.gov (United States)

    Wu, Swei-Pi; Loiu, Yi; Chien, Te Hong

    2015-01-01

    This study utilizes a psychophysical approach to examine the effects on carrying capacity for bi-manual carrying tasks involving different handle positions and carrying ranges. A total of 16 female subjects participated in the experiment in groups of two people, and each group of subjects performed the tasks in a random order with 12 different combinations of carrying task. The independent variables are handle position (upper, middle, lower) and carrying range (F-F: floor height carried to floor height, F-W: floor height carried to waist height, W-W: waist height carried to waist height, W-F: waist height carried to floor height), the dependent variable is the maximum acceptable carried weight (MAWC), heart rate (HR), and the rating of perceived exertion (RPE). The results show that the handle position has a significant effect on MAWC and overall RPE but no significant effect on HR. Carrying range has a significant effect on the MAWC and HR, but no significant effect on overall HR. The handle position and carrying range have a significant interaction on the MAWC and HR. The RPE for different body parts shows significant differences, and the hands feel the most tired. Overall, this study confirms that the lower handle position with the W-W carrying range is the best combination for a two-person carrying task.

  11. Recombinant Marburg viruses containing mutations in the IID region of VP35 prevent inhibition of Host immune responses.

    Science.gov (United States)

    Albariño, César G; Wiggleton Guerrero, Lisa; Spengler, Jessica R; Uebelhoer, Luke S; Chakrabarti, Ayan K; Nichol, Stuart T; Towner, Jonathan S

    2015-02-01

    Previous in vitro studies have demonstrated that Ebola and Marburg virus (EBOV and MARV) VP35 antagonize the host cell immune response. Moreover, specific mutations in the IFN inhibitory domain (IID) of EBOV and MARV VP35 that abrogate their interaction with virus-derived dsRNA, lack the ability to inhibit the host immune response. To investigate the role of MARV VP35 in the context of infectious virus, we used our reverse genetics system to generate two recombinant MARVs carrying specific mutations in the IID region of VP35. Our data show that wild-type and mutant viruses grow to similar titers in interferon deficient cells, but exhibit attenuated growth in interferon-competent cells. Furthermore, in contrast to wild-type virus, both MARV mutants were unable to inhibit expression of various antiviral genes. The MARV VP35 mutants exhibit similar phenotypes to those previously described for EBOV, suggesting the existence of a shared immune-modulatory strategy between filoviruses.

  12. Optimal growth trajectories with finite carrying capacity.

    Science.gov (United States)

    Caravelli, F; Sindoni, L; Caccioli, F; Ududec, C

    2016-08-01

    We consider the problem of finding optimal strategies that maximize the average growth rate of multiplicative stochastic processes. For a geometric Brownian motion, the problem is solved through the so-called Kelly criterion, according to which the optimal growth rate is achieved by investing a constant given fraction of resources at any step of the dynamics. We generalize these finding to the case of dynamical equations with finite carrying capacity, which can find applications in biology, mathematical ecology, and finance. We formulate the problem in terms of a stochastic process with multiplicative noise and a nonlinear drift term that is determined by the specific functional form of carrying capacity. We solve the stochastic equation for two classes of carrying capacity functions (power laws and logarithmic), and in both cases we compute the optimal trajectories of the control parameter. We further test the validity of our analytical results using numerical simulations.

  13. Optimal growth trajectories with finite carrying capacity

    Science.gov (United States)

    Caravelli, F.; Sindoni, L.; Caccioli, F.; Ududec, C.

    2016-08-01

    We consider the problem of finding optimal strategies that maximize the average growth rate of multiplicative stochastic processes. For a geometric Brownian motion, the problem is solved through the so-called Kelly criterion, according to which the optimal growth rate is achieved by investing a constant given fraction of resources at any step of the dynamics. We generalize these finding to the case of dynamical equations with finite carrying capacity, which can find applications in biology, mathematical ecology, and finance. We formulate the problem in terms of a stochastic process with multiplicative noise and a nonlinear drift term that is determined by the specific functional form of carrying capacity. We solve the stochastic equation for two classes of carrying capacity functions (power laws and logarithmic), and in both cases we compute the optimal trajectories of the control parameter. We further test the validity of our analytical results using numerical simulations.

  14. Zika Virus

    Science.gov (United States)

    Zika is a virus that is spread mostly by mosquitoes. A pregnant mother can pass it to ... through blood transfusions. There have been outbreaks of Zika virus in the United States, Africa, Southeast Asia, ...

  15. Chikungunya Virus

    Science.gov (United States)

    ... Gaines, PhD, MPH, MA, CHES Differentiating Chikungunya From Dengue: A Clinical Challenge For Travelers CDC Travelers' Health Chikungunya Virus Home Prevention Transmission Symptoms & Treatment Geographic Distribution Chikungunya virus in ...

  16. Chikungunya virus

    Science.gov (United States)

    Chikungunya virus infection; Chikungunya ... Where Chikungunya is found Before 2013, the virus was found in Africa, Asia, Europe, and the Indian and Pacific oceans. In late 2013, outbreaks occurred for the first time in the ...

  17. Carry Select Adder Circuit with A Successively Incremented Carry Number Block

    Directory of Open Access Journals (Sweden)

    Deepak

    2014-04-01

    Full Text Available This paper reports a conditional carry select (CCS adder circuit with a successively-incremented-carry-number block (SICNB structure for low-voltage VLSI implementation. Owing to the successively-incremented-carry-number block (SICNB structure, the new 16-bit SICNB CCS adder provides a 37% faster speed as compared to the conventional conditional Carry select adder based on the SPICE results

  18. A Feminist Reading of Sister Carrie

    Institute of Scientific and Technical Information of China (English)

    Wang Jiatong

    2015-01-01

    In the history of American literature,Sister Carrie is the first novel of Theodore Dreiser,it impresses people deeply. Carrie,a poor country girl,becomes a famous star in a big city. She has totally changed from her hard experiences,and she becomes financially independent as a new woman when she goes through hesitation.In he whole novel,the author has planted some strong points of Carrie’s character.At the end of this paper,it analyzes woman’s status in modern time from two aspects of the improvement of female’s social status and the comparison between men and women.

  19. Semiactive control for vibration attenuation

    Energy Technology Data Exchange (ETDEWEB)

    Leitmann, G. [Univ. of California, Berkeley, CA (United States). Coll. of Engineering

    1994-12-31

    With the advent of materials, such as electrorheological fluids, whose material properties can be altered rapidly by means of external stimuli, employing such materials as actuators for the controlled attenuation of undesirable vibrations is now possible. Such control schemes are dubbed semiactive in that they attenuate vibrations whether applied actively or passively. The author investigates various such control schemes, allowing for both separate and joint control of the stiffness and damping characteristics of the material.

  20. Land Potential Productivity and Population Carrying Capacity of Yan’an City

    Institute of Scientific and Technical Information of China (English)

    Xiaoling; LIU; Wei; ZHANG

    2013-01-01

    The productivity attenuation method is adopted to calculate land potential productivity of counties of Yan’an City and calculate population carrying capacity at current productivity level. Result shows that high photosynthetic potential productivity area and high light and temperature potential productivity area are mainly situated in the north,while high climatic potential area and high land potential productivity area are mainly concentrated in the south. From solar radiation,moisture and landform,the attenuation amplitude of land potential productivity in northern counties ( districts) is greater than that in southern counties ( districts) . In the whole city,the population carrying capacity of 9 counties reaches well-off living level,and 1 district still does not reach the level of adequate food and clothing. These results can provide reference for land resource use,agricultural production distribution and population growth control.

  1. Generation and preclinical evaluation of a DENV-1/2 prM+E chimeric live attenuated vaccine candidate with enhanced prM cleavage.

    Science.gov (United States)

    Keelapang, Poonsook; Nitatpattana, Narong; Suphatrakul, Amporn; Punyahathaikul, Surat; Sriburi, Rungtawan; Pulmanausahakul, Rojjanaporn; Pichyangkul, Sathit; Malasit, Prida; Yoksan, Sutee; Sittisombut, Nopporn

    2013-10-17

    In the absence of a vaccine or sustainable vector control measures, illnesses caused by dengue virus infection remain an important public health problem in many tropical countries. During the export of dengue virus particles, furin-mediated cleavage of the prM envelope protein is usually incomplete, thus generating a mixture of immature, partially mature and mature extracellular particles. Variations in the arrangement and conformation of the envelope proteins among these particles may be associated with their different roles in shaping the antibody response. In an attempt to improve upon live, attenuated dengue vaccine approaches, a mutant chimeric virus, with enhanced prM cleavage, was generated by introducing a cleavage-enhancing substitution into a chimeric DENV-1/2 virus genome, encoding the prM+E sequence of a recent DENV-1 isolate under an attenuated DENV-2 genetic background. A modest increase in virus specific infectivity observed in the mutant chimeric virus affected neither the attenuation phenotype, when assessed in the suckling mouse neurovirulence model, nor multiplication in mosquitoes. The two chimeric viruses induced similar levels of anti-DENV-1 neutralizing antibody response in mice and rhesus macaques, but more efficient control of viremia during viral challenge was observed in macaques immunized with the mutant chimeric virus. These results indicate that the DENV-1/2 chimeric virus, with enhanced prM cleavage, could be useful as an alternative live, attenuated vaccine candidate for further tests in humans.

  2. Error propagation in energetic carrying capacity models

    Science.gov (United States)

    Pearse, Aaron T.; Stafford, Joshua D.

    2014-01-01

    Conservation objectives derived from carrying capacity models have been used to inform management of landscapes for wildlife populations. Energetic carrying capacity models are particularly useful in conservation planning for wildlife; these models use estimates of food abundance and energetic requirements of wildlife to target conservation actions. We provide a general method for incorporating a foraging threshold (i.e., density of food at which foraging becomes unprofitable) when estimating food availability with energetic carrying capacity models. We use a hypothetical example to describe how past methods for adjustment of foraging thresholds biased results of energetic carrying capacity models in certain instances. Adjusting foraging thresholds at the patch level of the species of interest provides results consistent with ecological foraging theory. Presentation of two case studies suggest variation in bias which, in certain instances, created large errors in conservation objectives and may have led to inefficient allocation of limited resources. Our results also illustrate how small errors or biases in application of input parameters, when extrapolated to large spatial extents, propagate errors in conservation planning and can have negative implications for target populations.

  3. Increased carrying capacity with perennial forage kochia

    Science.gov (United States)

    Carrying capacity can be increased on grass-dominated rangeland pastures by including perennial forage kochia (Kochia prostrata) as one of the plant components. The objectives of the study reported here were to compare the differences of traditional winter pastures versus pastures with forage kochi...

  4. 78 FR 43219 - Prospective Grant of Exclusive License: Live Attenuated Dengue Tetravalent Vaccine Containing a...

    Science.gov (United States)

    2013-07-19

    ... means for prevention of dengue infection and dengue hemorrhagic fever (DHF) by immunization with... Dengue Tetravalent Vaccine Containing a Common 30 Nucleotide Deletion in the 3'-UTR of Dengue Types 1, 2... et al., ``Development of Mutations Useful for Attenuating Dengue Viruses and Chimeric Dengue...

  5. PRRSV 野毒感染猪群免疫接种弱毒活疫苗的效果分析%Analysis of the Immune Efficacy of Attenuated Live Vaccine in the Pig Herds Previously Infected with Wild-type Porcine Reproductive and Respiratory Syndrome Virus

    Institute of Scientific and Technical Information of China (English)

    许心婷; 施开创; 李常挺; 龙飞翔; 莫胜兰; 陈汉忠

    2016-01-01

    为评估猪繁殖与呼吸综合征(porcine reproductive and respiratory syndrome,PRRS)弱毒活疫苗的免疫效果,本研究在两个小型猪场各选取两窝仔猪,在免疫接种猪繁殖与呼吸综合征病毒(porcine reproductive and respiratory syndrome virus,PRRSV)弱毒活疫苗后不同时间采集血清,应用 RT-PCR 检测 PRRSV 核酸,应用N-ELISA和 G-ELISA 两种试剂盒检测 PRRSV 抗体。结果发现,免疫前0 d 可以从仔猪血清中检测到 PRRSV 野毒株核酸,可持续到免疫后30 d;相对应的母猪在免疫前0 d 可从血清中检测到 PRRSV 野毒株核酸。试验仔猪在免疫前0 d 未能检测到 PRRSV 抗体,但在免疫后30~150 d 均可检测到 PRRSV 抗体,其中N-ELISA试剂盒的阳性检出率在免疫后30、60 d 高于 G-ELISA 试剂盒的阳性检出率,而在免疫后120、150 d 则低于 G-ELISA 试剂盒的阳性检出率。使用两种 ELISA 试剂盒共同检测216份血清样品,检测结果的总体符合率为95.83%;配对χ2检验,P >0.05,两者差异不显著;Kappa 值为0.87,属于极强一致性;两者相关系数 r 为0.605,具有显著线性相关。表明免疫接种弱毒活疫苗可以有效清除野毒感染猪群中的野毒株,N-ELISA 和 G-ELISA 两种 ELISA 试剂盒均可用于评估弱毒活疫苗的免疫效果。%To evaluate the immune efficacy of porcine reproductive and respiratory syndrome (PRRS)attenuated live vaccine,this study selected 4 litters from two small pig farms (two litters each farm)and vaccinated with porcine reproductive and respiratory syndrome virus (PRRSV)at-tenuated live vaccine.Sera were collected on different days post vaccination (dpv)to detect PRRSV nucleic acid by RT-PCR,and PRRSV antibody using two different ELISA Kits,i.e. N-ELISA and G-ELISA.The results showed that PRRSV nucleic acid were positive on 0 dpv until 30 dpv in piglets and also positive on 0 dpv in the corresponding sows.All piglets were negative for PRRSV antibody on 0 dpv,but were

  6. Consideration of natural attenuation. In remedation contaminated sites

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-04-15

    Upon the proposal submitted by ist Standing committee 5 (Contaminated Sites Committee - ALA) the Federal / State Working Group on Soil protection employed an ad hoc subcommittee dealing with considering natural attenuation in remediating contaminated sites and preparing an inter-State position paper. In the present position paper the way how to consider natural attenuation in practical remediation of contaminated sites is described. The systematic approach outlined allows an understandable decision-finding. A way is shown how the competent soil protection authorities may exercise discretion and in the framework of checking the appropriateness of measures may decide on the implementation of MNA based on a MNA concept (MNA = monitored natural attenuation). It is, however, also explained that when carrying out MNA a decision always made in an individual case is concerned which should be made in a close agreement between the obligated party and the authority.

  7. Oral Immunization with Recombinant Listeria monocytogenes Controls Virus Load after Vaginal Challenge with Feline Immunodeficiency Virus

    OpenAIRE

    Stevens, Rosemary; Howard, Kristina E.; Nordone, Sushila; Burkhard, MaryJo; Dean, Gregg A

    2004-01-01

    Recombinant Listeria monocytogenes has many attractive characteristics as a vaccine vector against human immunodeficiency virus (HIV). Wild-type and attenuated Listeria strains expressing HIV Gag have been shown to induce long-lived mucosal and systemic T-cell responses in mice. Using the feline immunodeficiency virus (FIV) model of HIV we evaluated recombinant L. monocytogenes in a challenge system. Five cats were immunized with recombinant L. monocytogenes that expresses the FIV Gag and del...

  8. Postexposure Protection Against Marburg Haemorrhagic Fever with Recombinant Vesicular Stomatitis Virus Vectors in Non-Human Primates: An Efficacy Assessment

    Science.gov (United States)

    2006-04-29

    virus (MARV). We aimed to test the effi cacy of a replication -competent vaccine based on attenuated recombinant vesicular stomatitis virus (rVSV...including vaccines based on recombinant adenoviruses12,13 and recombinant alphaviruses .8 We previously described the generation and assessment of a live...such as Marburg virus (MARV). We aimed to test the efficacy of a replication -competent vaccine based on attenuated recombinant vesicular stomatitis

  9. 携带p53基因的重组1型单纯疱疹病毒溶瘤特性的实验观察%Oncolytic property of HSV-1 recombinant viruses carrying the p53 gene

    Institute of Scientific and Technical Information of China (English)

    王雪莹; 朱慧; 汪习; 刘晓娟; 马正海

    2016-01-01

    Objective To obtain the recombinant herpes simplex virus 1 (HSV-1) inserted p53 gene with homologous recombination technology and investigate the virus' replication ability and oncolytic property in vitro and in vivo.Methods A eukaryotic expression case with p53 gene was cloned into pKOS/BN.The pKOS/p53 was constructed and transfected to the E.coli with pHSV△IR-BAC by electroporation.Then the recombinant pHSV△IR-BAC/p53 was obtained and transfected into Vero cells.Recombinant virus (MH1004) was identified by Southern blot and Western blot.Then the virus' replication abilities in several human tumors cells were tested by plaque assay.A murine melanoma model was established by subcutaneous inoculation of B16 cells.A dosage of 2 × 106 PFU (plaque forming unit) of MH1004,MH1001,HSV-1 wt or PBS was injected 3 times intratumorally in every 3 days.The tumor volume and survival rate were measured twice a week.Results The results of Western blot showed that the p53 protein can be detected from the Vero cells infected by MH1004.The replication abilities of MH1004 and HSV-1 wt in the same tumor cell was insignificant (P > 0.05).And MH1004's replication abilities in SK-N-SH and U251 was significantly higher than other cancer cells.The tumors volume of group HSV-1 wt,MH1001 (HSV△IR) and MH1004 were (6 180 ±751),(5 760 ±267) and (4 850 ±532) mm3 compared with PBS group (9 860 ± 91) mm3,the difference of reduction of tumors volume was significant (P < 0.01).And the tumors volume of MH1004 group was smaller than HSV-1 wt and MH1001 group,but without significant difference (P > 0.05).And the survival rate of MH1004 treated mice (5/6) was greatly higher than PBS (3/6),HSV-1 wt (3/6) and MH1001 (3/6).Conclusion The replication abilities of MH1004 in neural tumor are very high and MH1004 can inhibit the growth of tumor so that prolong the survival of mice bearing mnurine melanoma.%目的 利用同源重组技术获得插入p53基因的重组1

  10. Like an eagle carries its young

    Directory of Open Access Journals (Sweden)

    Hans-Georg Wünch

    2016-04-01

    Full Text Available The picture of an eagle carrying its young on its wings (Dt 32:11 is a powerful and encouraging image of trust and security in God. It is particularly relevant for Western culture, where the eagle is a prominent symbol of power and strength. In recent years, though, the translation of the Hebrew term רֶשֶׁנ as ‘eagle’ has come into question and modern exegetes claim that it is more accurately translated as ‘vulture’. But can this really be a symbol of comfort? Furthermore, do eagles (or vultures even carry their young on their wings? This article intends to shed some light on these questions.Keywords: Old Testament; Deuteronomy; Eagle; Vulture

  11. A decimal carry-free adder

    Science.gov (United States)

    Nikmehr, Hooman; Phillips, Braden; Lim, Cheng-Chew

    2005-02-01

    Recently, decimal arithmetic has become attractive in the financial and commercial world including banking, tax calculation, currency conversion, insurance and accounting. Although computers are still carrying out decimal calculation using software libraries and binary floating-point numbers, it is likely that in the near future, all processors will be equipped with units performing decimal operations directly on decimal operands. One critical building block for some complex decimal operations is the decimal carry-free adder. This paper discusses the mathematical framework of the addition, introduces a new signed-digit format for representing decimal numbers and presents an efficient architectural implementation. Delay estimation analysis shows that the adder offers improved performance over earlier designs.

  12. Computer Simulation Instruction: Carrying out Chemical Experiments

    Directory of Open Access Journals (Sweden)

    Ibtesam Al-Mashaqbeh

    2014-05-01

    Full Text Available The purpose of this study was to investigate the effect of computer simulation Instruction (CSI on students' achievements: Carrying out chemical experiments to acquire chemical concepts for eleventh grade students. The subject of the study consisted two sections of a one girl's high school in Jordan. One section was randomly assigned to experimental group in which computer simulation Instruction (CSI was used, and the other section was randomly assigned to control group in which students were instructed by using the traditional teaching instruction. The findings indicated that there is progress on the part of the experimental group which used the computer simulation Instruction (CSI and this was reflected positively in the students’ achievement in carrying out chemical experiments to acquire chemical concepts.

  13. Proof-Carrying Code with Correct Compilers

    Science.gov (United States)

    Appel, Andrew W.

    2009-01-01

    In the late 1990s, proof-carrying code was able to produce machine-checkable safety proofs for machine-language programs even though (1) it was impractical to prove correctness properties of source programs and (2) it was impractical to prove correctness of compilers. But now it is practical to prove some correctness properties of source programs, and it is practical to prove correctness of optimizing compilers. We can produce more expressive proof-carrying code, that can guarantee correctness properties for machine code and not just safety. We will construct program logics for source languages, prove them sound w.r.t. the operational semantics of the input language for a proved-correct compiler, and then use these logics as a basis for proving the soundness of static analyses.

  14. A Feminist Reading of Sister Carrie

    Institute of Scientific and Technical Information of China (English)

    Wang; Jiatong

    2015-01-01

    In the history of American literature,Sister Carrie is the first novel of Theodore Dreiser,it impresses people deeply.Carrie,a poor country girl,becomes a famous star in a big city.She has totally changed from her hard experiences,and she becomes financially independent as a new woman when she goes through hesitation.In he whole novel,the author has planted some strong points of Carrie’s character.At the end of this paper,it analyzes woman’s status in modern time from two aspects of the improvement of female’s social status and the comparison between men and women.

  15. Myxoma virus and the Leporipoxviruses: an evolutionary paradigm.

    Science.gov (United States)

    Kerr, Peter J; Liu, June; Cattadori, Isabella; Ghedin, Elodie; Read, Andrew F; Holmes, Edward C

    2015-03-06

    Myxoma virus (MYXV) is the type species of the Leporipoxviruses, a genus of Chordopoxvirinae, double stranded DNA viruses, whose members infect leporids and squirrels, inducing cutaneous fibromas from which virus is mechanically transmitted by biting arthropods. However, in the European rabbit (Oryctolagus cuniculus), MYXV causes the lethal disease myxomatosis. The release of MYXV as a biological control for the wild European rabbit population in Australia, initiated one of the great experiments in evolution. The subsequent coevolution of MYXV and rabbits is a classic example of natural selection acting on virulence as a pathogen adapts to a novel host species. Slightly attenuated mutants of the progenitor virus were more readily transmitted by the mosquito vector because the infected rabbit survived longer, while highly attenuated viruses could be controlled by the rabbit immune response. As a consequence, moderately attenuated viruses came to dominate. This evolution of the virus was accompanied by selection for genetic resistance in the wild rabbit population, which may have created an ongoing co-evolutionary dynamic between resistance and virulence for efficient transmission. This natural experiment was repeated on a continental scale with the release of a separate strain of MYXV in France and its subsequent spread throughout Europe. The selection of attenuated strains of virus and resistant rabbits mirrored the experience in Australia in a very different environment, albeit with somewhat different rates. Genome sequencing of the progenitor virus and the early radiation, as well as those from the 1990s in Australia and Europe, has shown that although MYXV evolved at high rates there was no conserved route to attenuation or back to virulence. In contrast, it seems that these relatively large viral genomes have the flexibility for multiple pathways that converge on a similar phenotype.

  16. Myxoma Virus and the Leporipoxviruses: An Evolutionary Paradigm

    Directory of Open Access Journals (Sweden)

    Peter J. Kerr

    2015-03-01

    Full Text Available Myxoma virus (MYXV is the type species of the Leporipoxviruses, a genus of Chordopoxvirinae, double stranded DNA viruses, whose members infect leporids and squirrels, inducing cutaneous fibromas from which virus is mechanically transmitted by biting arthropods. However, in the European rabbit (Oryctolagus cuniculus, MYXV causes the lethal disease myxomatosis. The release of MYXV as a biological control for the wild European rabbit population in Australia, initiated one of the great experiments in evolution. The subsequent coevolution of MYXV and rabbits is a classic example of natural selection acting on virulence as a pathogen adapts to a novel host species. Slightly attenuated mutants of the progenitor virus were more readily transmitted by the mosquito vector because the infected rabbit survived longer, while highly attenuated viruses could be controlled by the rabbit immune response. As a consequence, moderately attenuated viruses came to dominate. This evolution of the virus was accompanied by selection for genetic resistance in the wild rabbit population, which may have created an ongoing co-evolutionary dynamic between resistance and virulence for efficient transmission. This natural experiment was repeated on a continental scale with the release of a separate strain of MYXV in France and its subsequent spread throughout Europe. The selection of attenuated strains of virus and resistant rabbits mirrored the experience in Australia in a very different environment, albeit with somewhat different rates. Genome sequencing of the progenitor virus and the early radiation, as well as those from the 1990s in Australia and Europe, has shown that although MYXV evolved at high rates there was no conserved route to attenuation or back to virulence. In contrast, it seems that these relatively large viral genomes have the flexibility for multiple pathways that converge on a similar phenotype.

  17. Photoacoustic Imaging Taking into Account Attenuation

    CERN Document Server

    Kowar, Richard

    2010-01-01

    First, we review existing attenuation models and discuss their causality properties, which we believe to be essential for algorithms for inversion with attenuated data. Then, we survey causality properties of common attenuation models. We also derive integro-differential equations which the attenuated waves are satisfying. In addition we discuss the ill--conditionness of the inverse problem for calculating the unattenuated wave from the attenuated one.

  18. Attenuation in Superconducting Circular Waveguides

    Directory of Open Access Journals (Sweden)

    K. H. Yeap

    2016-09-01

    Full Text Available We present an analysis on wave propagation in superconducting circular waveguides. In order to account for the presence of quasiparticles in the intragap states of a superconductor, we employ the characteristic equation derived from the extended Mattis-Bardeen theory to compute the values of the complex conductivity. To calculate the attenuation in a circular waveguide, the tangential fields at the boundary of the wall are first matched with the electrical properties (which includes the complex conductivity of the wall material. The matching of fields with the electrical properties results in a set of transcendental equations which is able to accurately describe the propagation constant of the fields. Our results show that although the attenuation in the superconducting waveguide above cutoff (but below the gap frequency is finite, it is considerably lower than that in a normal waveguide. Above the gap frequency, however, the attenuation in the superconducting waveguide increases sharply. The attenuation eventually surpasses that in a normal waveguide. As frequency increases above the gap frequency, Cooper pairs break into quasiparticles. Hence, we attribute the sharp rise in attenuation to the increase in random collision of the quasiparticles with the lattice structure.

  19. Live attenuated varicella vaccine in children with leukemia in remission.

    Science.gov (United States)

    Gershon, A A; Steinberg, S; Galasso, G; Borkowsky, W; Larussa, P; Ferrara, A; Gelb, L

    1984-09-01

    One-hundred-ninety-one children with acute leukemia in remission for at least one year were immunized with 1 or more doses of live attenuated varicella vaccine. All were susceptible to varicella prior to vaccination. The only significant side effect was mild to moderate rash, seen especially in children with maintenance chemotherapy temporarily suspended for one week before and one week after vaccination. Children with rash were at some risk (10%) to transmit vaccine virus to varicella susceptibles with whom they had close contact.

  20. Genetic variation of S2 gene of the donkey leukocyte-attenuated vaccine strain of equine infectious anemia virus in experimentally infected horses%马传染性贫血病毒弱毒疫苗S2基因在体内变异分析

    Institute of Scientific and Technical Information of China (English)

    王帅; 王雪峰; 林跃智; 姜成刚; 吕晓玲; 赵立平; 周建华; 曲娟娟

    2011-01-01

    The variation of S2 gene of the equine infectious anemia virus (EIAV) attenuated vaccine adapted to cultivated donkey leukocytes was investigated by analysing virus replicated in experimentally infected horses. Two horses, #1 and #2, were inoculated with EIAVDLV121. Body temperature, viral RNA copy and platelet count of these horses were monitored for 6 months.Furthermore, the S2 gene of EIAVDLV121 was amplified by RT-PCR from plasma at different time points and sequenced. Results of sequence analysis showed that there were 6 consentaneous mutations in the S2 gene, which caused substitutions of translated amino acid residues in EIAV replicated in the hosts. In addition, the S2 genes amplified at the 70th day from horse #1 and at the 14th and 28th day from horse #2 had the highest homology to the consensus sequence of EIAVDLV121 S2 gene before inoculation.On the other hand, the S2 gene sequences of samples at the 42nd, 122nd, and 140th day from horse #1 appeared reduced divergence to the consensus S2 sequence of pathogenic strain EIAVLV40, which was the parental strain of EIAVDLV121. Our data on the EIAV S2 gene variation in vivo facilitate the studies on procedures of infection of pathogenic EIAV and vaccine strains.%为研究马传染性贫血病毒(EIAV)驴白细胞弱毒疫苗EIAVDLV121的S2基因在马体内的变异规律,本研究选用4匹成年马,其中2匹(#1、#2)接种EIAVDLV121,另外2匹作为对照.免疫后监测马体温、血小板含量以及病毒载量结果显示,免疫马未出现马传染性贫血体征.通过RT-PCR方法检测病毒S2基因在感染马体内不同时期的基因序列,结果显示,免疫马体内EIAVDLV121 S2蛋白的突变主要发生在氨基酸第17位、22位、39位、41位、51位和55位.另外,#1马免疫后70 d以及#2马免疫后第14 d和第28 d检测疫苗毒S2蛋白序列与EIAVDLV121亲缘关系较近,而#1马免疫后第42 d、第112 d和第140 d的疫苗毒S2蛋白序列与EIAVDLV121的

  1. DEVELOPEMENT OF A LIGHT ATTENUATOR BASED ON GLASSY REFLECTIONS

    Directory of Open Access Journals (Sweden)

    K. Ferria

    2015-07-01

    Full Text Available The light intensity control of a luminous source is a very important operation in many optical applications. Several types of light attenuator exploiting different optical phenomena like diffraction, absorption, and reflection exist and they differ principally in the maximum attenuation rate, the control range, the sensitivity and the spectral band. In the presented work, we have developed and designed a light attenuator based on the progressive decrease of the transmitted light intensity, when it undergoes multiple vitreous reflections across eight plates glasses arranged in a roof shape. Several tests were carried out using a laser light as a source. We have shown that the attenuation rate can be controlled by the choice of the incidence angle on the glasses slides, in addition we have confirmed, for the case of perpendicular polarization of the laser light, that the attenuation obeys to a linear function. The obtained results are very close to those predicted theoretically.

  2. Information carrying capacity of a cosmological constant

    Science.gov (United States)

    Simidzija, Petar; Martín-Martínez, Eduardo

    2017-01-01

    We analyze the exchange of information in different cosmological backgrounds when sender and receiver are timelike separated and communicate through massless fields (without the exchange of light signals). Remarkably, we show that the dominance of a cosmological constant makes the amount of recoverable information imprinted in the field by the sender extremely resilient: it does not decay in time or with the spatial separation of the sender and receiver, and it actually increases with the rate of expansion of the Universe. This is in stark contrast with the information carried by conventional light signals and with previous results on timelike communication through massless fields in matter-dominated cosmologies.

  3. Use of Tissue-Specific MicroRNA to Control Pathology of Wild-Type Adenovirus without Attenuation of Its Ability to Kill Cancer Cells

    NARCIS (Netherlands)

    Cawood, R.; Chen, H.H.; Carroll, F.; Bazan-Peregrino, M.; Rooijen, van N.; Seymour, L.W.

    2009-01-01

    Replicating viruses have broad applications in biomedicine, notably in cancer virotherapy and in the design of attenuated vaccines; however, uncontrolled virus replication in vulnerable tissues can give pathology and often restricts the use of potent strains. Increased knowledge of tissue-selective

  4. Mutations in the M-Gene Segment Can Substantially Increase Replication Efficiency of NS1 Deletion Influenza A Virus in MDCK Cells

    NARCIS (Netherlands)

    Wielink, van R.; Harmsen, M.M.; Martens, D.E.; Peeters, B.P.H.; Wijffels, R.H.; Moormann, R.J.M.

    2012-01-01

    Influenza viruses unable to express NS1 protein (delNS1) replicate poorly and induce high amounts of interferon (IFN). They are therefore considered as candidate viruses for live-attenuated influenza vaccines. Their attenuated replication is generally assumed to result from the inability to counter

  5. Sequence adaptations during growth of rescued classical swine fever viruses in cell culture and within infected pigs

    DEFF Research Database (Denmark)

    Hadsbjerg, Johanne; Friis, Martin Barfred; Fahnøe, Ulrik

    2016-01-01

    RNA could be detected. However, the animals inoculated with these mutant viruses seroconverted against CSFV. Thus, these mutant viruses were highly attenuated in vivo. All 4 rescued viruses were also passaged up to 20 times in cell culture. Using full genome sequencing, the same two adaptations within...... adaptation and to identify key determinants of viral replication efficiency in cells and within host animals....

  6. X-Ray Attenuation Cell

    Energy Technology Data Exchange (ETDEWEB)

    Ryutov, D.; Toor, A.

    2000-03-03

    To minimize the pulse-to-pulse variation, the LCLS FEL must operate at saturation, i.e. 10 orders of magnitude brighter spectral brilliance than 3rd-generation light sources. At this intensity, ultra-high vacuums and windowless transport are required. Many of the experiments, however, will need to be conducted at a much lower intensity thereby requiring a reliable means to reduce the x-ray intensity by many orders of magnitude without increasing the pulse-to-pulse variation. In this report we consider a possible solution for controlled attenuation of the LCLS x-ray radiation. We suggest using for this purpose a windowless gas-filled cell with the differential pumping. Although this scheme is easily realizable in principle, it has to be demonstrated that the attenuator can be made short enough to be practical and that the gas loads delivered to the vacuum line of sight (LOS) are acceptable. We are not going to present a final, optimized design. Instead, we will provide a preliminary analysis showing that the whole concept is robust and is worth further study. The spatial structure of the LCLS x-ray pulse at the location of the attenuator is shown in Fig. 1. The central high-intensity component, due to the FEL, has a FWHM of {approx}100 {micro}m. A second component, due to the undulator's broad band spontaneous radiation is seen as a much lower intensity ''halo'' with a FWHM of 1 mm. We discuss two versions of the attenuation cell. The first is directed towards a controlled attenuation of the FEL up to the 4 orders of magnitude in the intensity, with the spontaneous radiation halo being eliminated by collimators. In the second version, the spontaneous radiation is not sacrificed but the FEL component (as well as the first harmonic of the spontaneous radiation) gets attenuated by a more modest factor up to 100. We will make all the estimates assuming that the gas used in the attenuator is Xenon and that the energy of the FEL is 8.25 keV. At

  7. Using recombinant DNA technology for the development of live-attenuated dengue vaccines.

    Science.gov (United States)

    Lee, Hsiang-Chi; Butler, Michael; Wu, Suh-Chin

    2012-07-15

    Dramatic increases in dengue (DEN) incidence and disease severity have been reported, in great part due to the geographic expansion of Aedes aegypti and Aedes albopictus mosquitoes. One result is the expanded co-circulation of all dengue 1-4 serotype viruses (DENV) in urban areas worldwide, especially in South and South-East Asia, and South America. DEN disease severity ranges from asymptomatic infections to febrile dengue fevers (DF) to life-threatening dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). There is an urgent need for a safe and effective tetravalent DEN vaccine. Several live attenuated, tetravalent DEN vaccine candidates have been generated by recombinant DNA technology; these candidates are capable of providing immunity to all four DENV serotypes. In this paper we review (a) recombinant live-attenuated DEN vaccine candidates in terms of deletion, antigen chimerization, and the introduction of adaptive mutations; (b) strategies for improving tetravalent vaccine attenuation; and (c) live-attenuated DENV vaccine development.

  8. Attenuation in silica-based optical fibers

    DEFF Research Database (Denmark)

    Wandel, Marie Emilie

    2006-01-01

    In this thesis on attenuation in silica based optical fibers results within three main topics are reported. Spectral attenuation measurements on transmission fibers are performed in the wide wavelength range 290 nm – 1700 nm. The measured spectral attenuation is analyzed with special emphasis...... on absorption peaks in order to investigate the cause of an unusual high attenuation in a series of transmission fibers. Strong indications point to Ni2+ in octahedral coordination as being the cause of the high attenuation. The attenuation of fibers having a high core refractive index is analyzed and the cause...... of the high attenuation measured in such fibers is described as being due to scattering of light on fluctuations of the core diameter. A novel semi-empirical model for predicting the attenuation of high index fibers is presented. The model is shown to be able to predict the attenuation of high index fibers...

  9. Computer Virus

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Computer viruses are small software programs that are designed to spread from one computerto another and to interfere with computer operation.A virus might delete data on your computer,use your e-mail program to spread itself to othercomputers,or even erase everything on your hard disk.Viruses are most easily spread by attach-ments in e-mail messages or instant messaging messages.That is why it is essential that you never

  10. Life-Threatening Sochi Virus Infections, Russia.

    Science.gov (United States)

    Kruger, Detlev H; Tkachenko, Evgeniy A; Morozov, Vyacheslav G; Yunicheva, Yulia V; Pilikova, Olga M; Malkin, Gennadiy; Ishmukhametov, Aydar A; Heinemann, Patrick; Witkowski, Peter T; Klempa, Boris; Dzagurova, Tamara K

    2015-12-01

    Sochi virus was recently identified as a new hantavirus genotype carried by the Black Sea field mouse, Apodemus ponticus. We evaluated 62 patients in Russia with Sochi virus infection. Most clinical cases were severe, and the case-fatality rate was as high as 14.5%.

  11. Evasion of T cell immunity by Epstein-Barr virus

    NARCIS (Netherlands)

    Horst, D.

    2011-01-01

    Immune evasion strategies are thought to contribute essentially to the life cycle of persistent viruses by delaying the elimination of the infected cell long enough to enable the virus to replicate. Exemplary in this context are the herpesviruses, large DNA viruses that are carried as a persistent a

  12. Josephson tunnel junction microwave attenuator

    DEFF Research Database (Denmark)

    Koshelets, V. P.; Shitov, S. V.; Shchukin, A. V.

    1993-01-01

    A new element for superconducting electronic circuitry-a variable attenuator-has been proposed, designed, and successfully tested. The principle of operation is based on the change in the microwave impedance of a superconductor-insulator-superconductor (SIS) Josephson tunnel junction when dc bias...

  13. Compact plasmonic variable optical attenuator

    DEFF Research Database (Denmark)

    Leosson, Kristjan; Rosenzveig, Tiberiu; Hermannsson, Pétur Gordon

    2008-01-01

    We demonstrate plasmonic nanowire-based thermo-optic variable optical attenuators operating in the 1525-1625 nm wavelength range. The devices have a footprint as low as 1 mm, extinction ratio exceeding 40 dB, driving voltage below 3 V, and full modulation bandwidth of 1 kHz. The polarization...

  14. Effects of human metapneumovirus and respiratory syncytial virus antigen insertion in two 3' proximal genome positions of bovine/human parainfluenza virus type 3 on virus replication and immunogenicity

    NARCIS (Netherlands)

    R.S. Tang (Roderick); J.H. Schickli (Jeanne); M. MacPhail (Mia); F. Fernandes (Fiona); L. Bicha (Leenas); J. Spaete (Joshua); R.A.M. Fouchier (Ron); A.D.M.E. Osterhaus (Albert); R. Spaete (Richard); A.A. Haller (Aurelia)

    2003-01-01

    textabstractA live attenuated bovine parainfluenza virus type 3 (PIV3), harboring the fusion (F) and hemagglutinin-neuraminidase (HN) genes of human PIV3, was used as a virus vector to express surface glycoproteins derived from two human pathogens, human metapneumovirus (hMPV) and respiratory syncyt

  15. Stormwater Attenuation by Green Roofs

    Science.gov (United States)

    Sims, A.; O'Carroll, D. M.; Robinson, C. E.; Smart, C. C.

    2014-12-01

    Innovative municipal stormwater management technologies are urgently required in urban centers. Inadequate stormwater management can lead to excessive flooding, channel erosion, decreased stream baseflows, and degraded water quality. A major source of urban stormwater is unused roof space. Green roofs can be used as a stormwater management tool to reduce roof generated stormwater and generally improve the quality of runoff. With recent legislation in some North American cities, including Toronto, requiring the installation of green roofs on large buildings, research on the effectiveness of green roofs for stormwater management is important. This study aims to assess the hydrologic response of an extensive sedum green roof in London, Ontario, with emphasis on the response to large precipitation events that stress municipal stormwater infrastructure. A green roof rapidly reaches field capacity during large storm events and can show significantly different behavior before and after field capacity. At field capacity a green roof has no capillary storage left for retention of stormwater, but may still be an effective tool to attenuate peak runoff rates by transport through the green roof substrate. The attenuation of green roofs after field capacity is linked to gravity storage, where gravity storage is the water that is temporarily stored and can drain freely over time after field capacity has been established. Stormwater attenuation of a modular experimental green roof is determined from water balance calculations at 1-minute intervals. Data is used to evaluate green roof attenuation and the impact of field capacity on peak flow rates and gravity storage. In addition, a numerical model is used to simulate event based stormwater attenuation. This model is based off of the Richards equation and supporting theory of multiphase flow through porous media.

  16. Genetic analysis of hantaviruses carried by Myodes and Microtus rodents in Buryatia

    Directory of Open Access Journals (Sweden)

    Lundkvist Åke

    2008-01-01

    Full Text Available Abstract Hantavirus genome sequences were recovered from tissue samples of Myodes rufocanus, Microtus fortis and Microtus oeconomus captured in the Baikal area of Buryatia, Russian Federation. Genetic analysis of S- and M-segment sequences of Buryatian hantavirus strains showed that Myodes-associated strains belong to Hokkaido virus (HOKV type while Microtus-associated strains belong to Vladivostok virus (VLAV type. On phylogenetic trees Buryatian HOKV strains were clustered together with M. rufocanus- originated strains from Japan, China and Far-East Russia (Primorsky region. Buryatian Microtus- originated strains shared a common recent ancestor with M. fortis- originated VLAV strain from Far-East Russia (Vladivostok area. Our data (i confirm that M. rufocanus carries a hantavirus which is similar to but distinct from both Puumala virus carried by M. glareolus and Muju virus associated with M. regulus, (ii confirm that M. fortis is the natural host for VLAV, and (iii suggest M. oeconomus as an alternative host for VLAV.

  17. DESIGN OF OPTIMAL CARRY SKIP ADDER AND CARRY SKIP BCD ADDER USING REVERSIBLE LOGIC GATES

    OpenAIRE

    Praveena Murugesan; Thanushkodi Keppanagounder

    2014-01-01

    Reversible logic circuits have the ability to produce zero power dissipation which has found its importance in quantum computing, optical computing and low power digital circuits. The study presents improved and efficient reversible logic circuits for carry skip adder and carry skip BCD adder. The performance of the proposed architecture is better than the existing works in terms of gate count, garbage outputs and constant inputs. This design forms the basis for different quantum ALU and embe...

  18. Rational design of a live attenuated dengue vaccine: 2'-o-methyltransferase mutants are highly attenuated and immunogenic in mice and macaques.

    Directory of Open Access Journals (Sweden)

    Roland Züst

    Full Text Available Dengue virus is transmitted by Aedes mosquitoes and infects at least 100 million people every year. Progressive urbanization in Asia and South-Central America and the geographic expansion of Aedes mosquito habitats have accelerated the global spread of dengue, resulting in a continuously increasing number of cases. A cost-effective, safe vaccine conferring protection with ideally a single injection could stop dengue transmission. Current vaccine candidates require several booster injections or do not provide protection against all four serotypes. Here we demonstrate that dengue virus mutants lacking 2'-O-methyltransferase activity are highly sensitive to type I IFN inhibition. The mutant viruses are attenuated in mice and rhesus monkeys and elicit a strong adaptive immune response. Monkeys immunized with a single dose of 2'-O-methyltransferase mutant virus showed 100% sero-conversion even when a dose as low as 1,000 plaque forming units was administrated. Animals were fully protected against a homologous challenge. Furthermore, mosquitoes feeding on blood containing the mutant virus were not infected, whereas those feeding on blood containing wild-type virus were infected and thus able to transmit it. These results show the potential of 2'-O-methyltransferase mutant virus as a safe, rationally designed dengue vaccine that restrains itself due to the increased susceptibility to the host's innate immune response.

  19. Computer Virus

    Institute of Scientific and Technical Information of China (English)

    高振桥

    2002-01-01

    If you work with a computer,it is certain that you can not avoid dealing, with at least one computer virus.But how much do you know about it? Well,actually,a computer virus is not a biological' one as causes illnesses to people.It is a kind of computer program

  20. Phytophthora viruses.

    Science.gov (United States)

    Cai, Guohong; Hillman, Bradley I

    2013-01-01

    Phytophthora sp. is a genus in the oomycetes, which are similar to filamentous fungi in morphology and habitat, but phylogenetically more closely related to brown algae and diatoms and fall in the kingdom Stramenopila. In the past few years, several viruses have been characterized in Phytophthora species, including four viruses from Phytophthora infestans, the late blight pathogen, and an endornavirus from an unnamed Phytophthora species from Douglas fir. Studies on Phytophthora viruses have revealed several interesting systems. Phytophthora infestans RNA virus 1 (PiRV-1) and PiRV-2 are likely the first members of two new virus families; studies on PiRV-3 support the establishment of a new virus genus that is not affiliated with established virus families; PiRV-4 is a member of Narnaviridae, most likely in the genus Narnavirus; and Phytophthora endornavirus 1 (PEV1) was the first nonplant endornavirus at the time of reporting. Viral capsids have not been found in any of the above-mentioned viruses. PiRV-1 demonstrated a unique genome organization that requires further examination, and PiRV-2 may have played a role in late blight resurgence in 1980s-1990s.

  1. Testability Synthesis for Jumping Carry Adders

    Directory of Open Access Journals (Sweden)

    Chien-In Henry Chen

    2002-01-01

    Full Text Available Synthesis for testability ensures that the synthesized circuit is testable by exploring the fundamental relationship between don't care and redundancy. With the exploration of the relationship, redundancy removal can be applied to improve the testability, reduce the area and improve the speed of a synthesized circuit. The test generation problems have been adequately solved, therefore an innovative testability synthesis strategy is necessary for achieving the maximum fault coverage and area reduction for maximum speed. This paper presents a testability synthesis methodology applicable to a top–down design method based on the identification and removal of redundant faults. Emphasis has been placed on the testability synthesis of a high-speed binary jumping carry adder. A synthesized 32-bit testable adder implemented by a 1.2 μm CMOS technology performs addition in 4.09 ns. Comparing with the original synthesized circuit, redundancy removal yields a 100% testable design with a 15% improvement in speed and a 25% reduction in area.

  2. Robust ferromagnetism carried by antiferromagnetic domain walls

    Science.gov (United States)

    Hirose, Hishiro T.; Yamaura, Jun-Ichi; Hiroi, Zenji

    2017-02-01

    Ferroic materials, such as ferromagnetic or ferroelectric materials, have been utilized as recording media for memory devices. A recent trend for downsizing, however, requires an alternative, because ferroic orders tend to become unstable for miniaturization. The domain wall nanoelectronics is a new developing direction for next-generation devices, in which atomic domain walls, rather than conventional, large domains themselves, are the active elements. Here we show that atomically thin magnetic domain walls generated in the antiferromagnetic insulator Cd2Os2O7 carry unusual ferromagnetic moments perpendicular to the wall as well as electron conductivity: the ferromagnetic moments are easily polarized even by a tiny field of 1 mT at high temperature, while, once cooled down, they are surprisingly robust even in an inverse magnetic field of 7 T. Thus, the magnetic domain walls could serve as a new-type of microscopic, switchable and electrically readable magnetic medium which is potentially important for future applications in the domain wall nanoelectronics.

  3. Retinal oscillations carry visual information to cortex

    Directory of Open Access Journals (Sweden)

    Kilian Koepsell

    2009-04-01

    Full Text Available Thalamic relay cells fire action potentials that transmit information from retina to cortex. The amount of information that spike trains encode is usually estimated from the precision of spike timing with respect to the stimulus. Sensory input, however, is only one factor that influences neural activity. For example, intrinsic dynamics, such as oscillations of networks of neurons, also modulate firing pattern. Here, we asked if retinal oscillations might help to convey information to neurons downstream. Specifically, we made whole-cell recordings from relay cells to reveal retinal inputs (EPSPs and thalamic outputs (spikes and then analyzed these events with information theory. Our results show that thalamic spike trains operate as two multiplexed channels. One channel, which occupies a low frequency band (<30 Hz, is encoded by average firing rate with respect to the stimulus and carries information about local changes in the visual field over time. The other operates in the gamma frequency band (40-80 Hz and is encoded by spike timing relative to retinal oscillations. At times, the second channel conveyed even more information than the first. Because retinal oscillations involve extensive networks of ganglion cells, it is likely that the second channel transmits information about global features of the visual scene.

  4. Insertion of reticuloendotheliosis virus long terminal repeat into a bacterial artificial chromosome clone of a very virulent Marek's disease virus alters its pathogenicity

    Science.gov (United States)

    Co-cultivation of strain JM/102W of Marek’s disease virus (MDV) with reticuloendotheliosis virus (REV) resulted in the generation of a recombinant MDV containing REV long terminal repeat (LTR) named RM1 strain of MDV; a strain that was highly attenuated for oncogenicity, but induced severe bursal an...

  5. Ferrite attenuator modulation improves antenna performance

    Science.gov (United States)

    Hooks, J. C.; Larson, S. G.; Shorkley, F. H.; Williams, B. T.

    1970-01-01

    Ferrite attenuator inserted into appropriate waveguide reduces the gain of the antenna element which is causing interference. Modulating the ferrite attenuator to change the antenna gain at the receive frequency permits ground tracking until the antenna is no longer needed.

  6. Neuraminidase as an enzymatic marker for detecting airborne Influenza virus and other viruses.

    Science.gov (United States)

    Turgeon, Nathalie; Toulouse, Marie-Josée; Ho, Jim; Li, Dongqing; Duchaine, Caroline

    2017-02-01

    Little information is available regarding the effectiveness of air samplers to collect viruses and regarding the effects of sampling processes on viral integrity. The neuraminidase enzyme is present on the surface of viruses that are of agricultural and medical importance. It has been demonstrated that viruses carrying this enzyme can be detected using commercial substrates without having to process the sample by methods such as RNA extraction. This project aims at evaluating the effects of 3 aerosol-sampling devices on the neuraminidase enzyme activity of airborne viruses. The purified neuraminidase enzymes from Clostridium perfringens, a strain of Influenza A (H1N1) virus, the FluMist influenza vaccine, and the Newcastle disease virus were used as models. The neuraminidase models were aerosolized in aerosol chambers and sampled with 3 different air samplers (SKC BioSampler, 3-piece cassettes with polycarbonate filters, and Coriolis μ) to assess the effect on neuraminidase enzyme activity. Our results demonstrated that Influenza virus and Newcastle disease virus neuraminidase enzymes are resistant to aerosolization and sampling with all air samplers tested. Moreover, we demonstrated that the enzymatic neuraminidase assay is as sensitive as RT-qPCR for detecting low concentrations of Influenza virus and Newcastle disease virus. Therefore, given the sensitivity of the assay and its compatibility with air sampling methods, viruses carrying the neuraminidase enzyme can be rapidly detected from air samples using neuraminidase activity assay without having to preprocess the samples.

  7. The role of IKKβ in Venezuelan equine encephalitis virus infection.

    Directory of Open Access Journals (Sweden)

    Moushimi Amaya

    Full Text Available Venezuelan equine encephalitis virus (VEEV belongs to the genus Alphavirus, family Togaviridae. VEEV infection is characterized by extensive inflammation and studies from other laboratories implicated an involvement of the NF-κB cascade in the in vivo pathology. Initial studies indicated that at early time points of VEEV infection, the NF-κB complex was activated in cells infected with the TC-83 strain of VEEV. One upstream kinase that contributes to the phosphorylation of p65 is the IKKβ component of the IKK complex. Our previous studies with Rift valley fever virus, which exhibited early activation of the NF-κB cascade in infected cells, had indicated that the IKKβ component underwent macromolecular reorganization to form a novel low molecular weight form unique to infected cells. This prompted us to investigate if the IKK complex undergoes a comparable macromolecular reorganization in VEEV infection. Size-fractionated VEEV infected cell extracts indicated a macromolecular reorganization of IKKβ in VEEV infected cells that resulted in formation of lower molecular weight complexes. Well-documented inhibitors of IKKβ function, BAY-11-7082, BAY-11-7085 and IKK2 compound IV, were employed to determine whether IKKβ function was required for the production of infectious progeny virus. A decrease in infectious viral particles and viral RNA copies was observed with inhibitor treatment in the attenuated and virulent strains of VEEV infection. In order to further validate the requirement of IKKβ for VEEV replication, we over-expressed IKKβ in cells and observed an increase in viral titers. In contrast, studies carried out using IKKβ(-/- cells demonstrated a decrease in VEEV replication. In vivo studies demonstrated that inhibitor treatment of TC-83 infected mice increased their survival. Finally, proteomics studies have revealed that IKKβ may interact with the viral protein nsP3. In conclusion, our studies have revealed that the host IKK

  8. Clinical evaluation strategies for a live attenuated tetravalent dengue vaccine.

    Science.gov (United States)

    Precioso, Alexander Roberto; Palacios, Ricardo; Thomé, Beatriz; Mondini, Gabriella; Braga, Patrícia; Kalil, Jorge

    2015-12-10

    Butantan Institute is a public Brazilian biomedical research-manufacturer center affiliated to the São Paulo State Secretary of Health. Currently, Butantan is one of the main public producers of vaccines, antivenoms, and antitoxins in Latin America. The partnership between Butantan and the National Institutes of Health (NIH) of the United Sates has been one of the longest and most successful partnerships in the development and manufacturing of new vaccines. Recently, Butantan Institute has developed and manufactured a lyophilized tetravalent live attenuated dengue vaccine with the four dengue viruses attenuated and licensed from the Laboratory of Infectious Diseases at The National Institutes of Allergy and Infectious Diseases (LID/NIAID/NIH). The objective of this paper is to describe the clinical evaluation strategies of a live attenuated tetravalent dengue vaccine (Butantan-DV) developed and manufactured by Butantan Institute. These clinical strategies will be used to evaluate the Butantan-DV Phase III trial to support the Butantan-DV licensure for protection against any symptomatic dengue caused by any serotype in people aged 2 to 59 years.

  9. Gairo virus, a novel arenavirus of the widespread Mastomys natalensis: Genetically divergent, but ecologically similar to Lassa and Morogoro viruses.

    Science.gov (United States)

    Gryseels, Sophie; Rieger, Toni; Oestereich, Lisa; Cuypers, Bart; Borremans, Benny; Makundi, Rhodes; Leirs, Herwig; Günther, Stephan; Goüy de Bellocq, Joëlle

    2015-02-01

    Despite its near pan-African range, the Natal multimammate mouse, Mastomys natalensis, carries the human pathogen Lassa virus only in West Africa, while the seemingly non-pathogenic arenaviruses Mopeia, Morogoro, and Luna have been detected in this semi-commensal rodent in Mozambique/Zimbabwe, Tanzania and Zambia, respectively. Here, we describe a novel arenavirus in M. natalensis from Gairo district of central Tanzania, for which we propose the name "Gairo virus". Surprisingly, the virus is not closely related with Morogoro virus that infects M. natalensis only 90km south of Gairo, but clusters phylogenetically with Mobala-like viruses that infect non-M. natalensis host species in Central African Republic and Ethiopia. Despite the evolutionary distance, Gairo virus shares basic ecological features with the other M. natalensis-borne viruses Lassa and Morogoro. Our data show that M. natalensis, carrying distantly related viruses even in the same geographical area, is a potent reservoir host for a variety of arenaviruses.

  10. ENHANCEMENTS TO NATURAL ATTENUATION: SELECTED CASE STUDIES

    Energy Technology Data Exchange (ETDEWEB)

    Vangelas, K; W. H. Albright, W; E. S. Becvar, E; C. H. Benson, C; T. O. Early, T; E. Hood, E; P. M. Jardine, P; M. Lorah, M; E. Majche, E; D. Major, D; W. J. Waugh, W; G. Wein, G; O. R. West, O

    2007-05-15

    In 2003 the US Department of Energy (DOE) embarked on a project to explore an innovative approach to remediation of subsurface contaminant plumes that focused on introducing mechanisms for augmenting natural attenuation to achieve site closure. Termed enhanced attenuation (EA), this approach has drawn its inspiration from the concept of monitored natural attenuation (MNA).

  11. Comparative analysis of chrysanthemum transcriptome in response to three RNA viruses: Cucumber mosaic virus, Tomato spotted wilt virus and Potato virus X.

    Science.gov (United States)

    Choi, Hoseong; Jo, Yeonhwa; Lian, Sen; Jo, Kyoung-Min; Chu, Hyosub; Yoon, Ju-Yeon; Choi, Seung-Kook; Kim, Kook-Hyung; Cho, Won Kyong

    2015-06-01

    The chrysanthemum is one of popular flowers in the world and a host for several viruses. So far, molecular interaction studies between the chrysanthemum and viruses are limited. In this study, we carried out a transcriptome analysis of chrysanthemum in response to three different viruses including Cucumber mosaic virus (CMV), Tomato spotted wilt virus (TSWV) and Potato virus X (PVX). A chrysanthemum 135K microarray derived from expressed sequence tags was successfully applied for the expression profiles of the chrysanthemum at early stage of virus infection. Finally, we identified a total of 125, 70 and 124 differentially expressed genes (DEGs) for CMV, TSWV and PVX, respectively. Many DEGs were virus specific; however, 33 DEGs were commonly regulated by three viruses. Gene ontology (GO) enrichment analysis identified a total of 132 GO terms, and of them, six GO terms related stress response and MCM complex were commonly identified for three viruses. Several genes functioning in stress response such as chitin response and ethylene mediated signaling pathway were up-regulated indicating their involvement in establishment of host immune system. In particular, TSWV infection significantly down-regulated genes related to DNA metabolic process including DNA replication, chromatin organization, histone modification and cytokinesis, and they are mostly targeted to nucleosome and MCM complex. Taken together, our comparative transcriptome analysis revealed several genes related to hormone mediated viral stress response and DNA modification. The identified chrysanthemums genes could be good candidates for further functional study associated with resistant to various plant viruses.

  12. Chlorine signal attenuation in concrete.

    Science.gov (United States)

    Naqvi, A A; Maslehuddin, M; ur-Rehman, Khateeb; Al-Amoudi, O S B

    2015-11-01

    The intensity of prompt gamma-ray was measured at various depths from chlorine-contaminated silica fume (SF) concrete slab concrete specimens using portable neutron generator-based prompt gamma-ray setup. The intensity of 6.11MeV chloride gamma-rays was measured from the chloride contaminated slab at distance of 15.25, 20.25, 25.25, 30.25 and 35.25cm from neutron target in a SF cement concrete slab specimens. Due to attenuation of thermal neutron flux and emitted gamma-ray intensity in SF cement concrete at various depths, the measured intensity of chlorine gamma-rays decreases non-linearly with increasing depth in concrete. A good agreement was noted between the experimental results and the results of Monte Carlo simulation. This study has provided useful experimental data for evaluating the chloride contamination in the SF concrete utilizing gamma-ray attenuation method.

  13. Efficient carry skip Adder design using full adder and carry skip block based on reversible Logic

    Directory of Open Access Journals (Sweden)

    Varun Pratap Singh

    2015-12-01

    Full Text Available In recent years, Reversible Logic is becoming more and more prominent technology having its applications in Quantum Computing, Nanotechnology, and Optical Computing. Reversibility plays an important role when energy efficient computations are considered. In this paper, binary full Adder with Design I and Design II are proposed. The performance analysis is verified using number of reversible gates, Garbage input/outputs, delay, number of logical calculations and Quantum Cost. According to the suitability of full adder design I and design II carry skip adder block is also constructed with some improvement in terms of delay in block carry generation. It is observed that Reversible carry skip Binary Adder with Design II is efficient compared to Design I

  14. PAUT inspection of copper canister: Structural attenuation and POD formulation

    Science.gov (United States)

    Gianneo, A.; Carboni, M.; Mueller, C.; Ronneteg, U.

    2016-02-01

    For inspection of thick-walled (50mm) copper canisters for final disposal of spent nuclear fuel in Sweden, ultrasonic inspection using phased array technique (PAUT) is applied. Because thick-walled copper is not commonly used as a structural material, previous experience on Phased Array Ultrasonic Testing for this type of application is limited. The paper presents the progress in understanding the amplitudes and attenuation changes acting on the Phased Array Ultrasonic Testing inspection of copper canisters. Previous studies showed the existence of a low pass filtering effect and a heterogeneous grain size distribution along the depth, thus affecting both the detectability of defects and their "Probability of Detection" determination. Consequently, the difference between the first and second back wall echoes were not sufficient to determine the local attenuation (within the inspection range), which affects the signal response for each individual defect. Experimental evaluation of structural attenuation was carried out onto step-wedge samples cut from full-size, extruded and pierced & drawn, copper canisters. Effective attenuation values has been implemented in numerical simulations to achieve a Multi Parameter Probability of Detection and to formulate a Model Assisted Probability of Detection through a Monte-Carlo extraction model.

  15. Laboratory measurements of seismic attenuation in partially saturated rocks

    Science.gov (United States)

    Chapman, Samuel; Tisato, Nicola; Quintal, Beatriz; Holliger, Klaus

    2014-05-01

    Laboratory measurements of seismic attenuation and transient pore fluid pressure are performed on partially saturated Berea sandstone and synthetic borosilicate samples. Various degrees of water (liquid) and nitrogen (gas) saturation are considered. These measurements are carried out at room temperature and under confining pressures varying from ambient conditions up to 25 MPa. The cylindrical samples are 25 cm long and have a diameter of 7.6 cm. In the context of the experimental setup, the solid frames of both the Berea sandstone and the borosilicate samples can be considered homogenous, which in turn allows for isolating and exploring the effects of partial saturation on seismic attenuation. We employ the sub-resonance method, which is based on the application of a time-harmonic vertical stress to the top of the sample and the measurement of the thus resulting strain. For any given frequency, the attenuation is then inferred as the tangent of the phase shift between the applied stress and the observed strain. Using five equally spaced sensors along the central axis of the cylindrical sample, we measure the transient fluid pressure induced by the application of a step-function-type vertical stress to the top of the sample. Both the sensors and the sample are sealed off with the regard to the confining environment. Together with the numerical results from corresponding compressibility tests based on the quasi-static poroelastic equations, these transient fluid pressure measurements are then used to assist the interpretation of the seismic attenuation measurements.

  16. Inhibitors of the interferon response enhance virus replication in vitro.

    Directory of Open Access Journals (Sweden)

    Claire E Stewart

    Full Text Available Virus replication efficiency is influenced by two conflicting factors, kinetics of the cellular interferon (IFN response and induction of an antiviral state versus speed of virus replication and virus-induced inhibition of the IFN response. Disablement of a virus's capacity to circumvent the IFN response enables both basic research and various practical applications. However, such IFN-sensitive viruses can be difficult to grow to high-titer in cells that produce and respond to IFN. The current default option for growing IFN-sensitive viruses is restricted to a limited selection of cell-lines (e.g. Vero cells that have lost their ability to produce IFN. This study demonstrates that supplementing tissue-culture medium with an IFN inhibitor provides a simple, effective and flexible approach to increase the growth of IFN-sensitive viruses in a cell-line of choice. We report that IFN inhibitors targeting components of the IFN response (TBK1, IKK2, JAK1 significantly increased virus replication. More specifically, the JAK1/2 inhibitor Ruxolitinib enhances the growth of viruses that are sensitive to IFN due to (i loss of function of the viral IFN antagonist (due to mutation or species-specific constraints or (ii mutations/host cell constraints that slow virus spread such that it can be controlled by the IFN response. This was demonstrated for a variety of viruses, including, viruses with disabled IFN antagonists that represent live-attenuated vaccine candidates (Respiratory Syncytial Virus (RSV, Influenza Virus, traditionally attenuated vaccine strains (Measles, Mumps and a slow-growing wild-type virus (RSV. In conclusion, supplementing tissue culture-medium with an IFN inhibitor to increase the growth of IFN-sensitive viruses in a cell-line of choice represents an approach, which is broadly applicable to research investigating the importance of the IFN response in controlling virus infections and has utility in a number of practical applications

  17. Mechanisms of geometrical seismic attenuation

    Directory of Open Access Journals (Sweden)

    Igor B. Morozov

    2011-07-01

    Full Text Available In several recent reports, we have explained the frequency dependence of the apparent seismic quality-factor (Q observed in many studies according to the effects of geometrical attenuation, which was defined as the zero-frequency limit of the temporal attenuation coefficient. In particular, geometrical attenuation was found to be positive for most waves traveling within the lithosphere. Here, we present three theoretical models that illustrate the origin of this geometrical attenuation, and we investigate the causes of its preferential positive values. In addition, we discuss the physical basis and limitations of both the conventional and new attenuation models. For waves in media with slowly varying properties, geometrical attenuation is caused by variations in the wavefront curvature, which can be both positive (for defocusing and negative (for focusing. In media with velocity/density contrasts, incoherent reflectivity leads to geometrical-attenuation coefficients which are proportional to the mean squared reflectivity and are always positive. For «coherent» reflectivity, the geometrical attenuation is approximately zero, and the attenuation process can be described according to the concept of «scattering Q». However, the true meaning of this parameter is in describing the mean reflectivity within the medium, and not that of the traditional resonator quality factor known in mechanics. The general conclusion from these models is that non-zero and often positive levels of geometrical attenuation are common in realistic, heterogeneous media, both observationally and theoretically. When transformed into the conventional Q-factor form, this positive geometrical attenuation leads to Q values that quickly increase with frequency. These predictions show that the positive frequency-dependent Q observed in many datasets might represent artifacts of the transformations of the attenuation coefficients into Q.

  1. Competitive Fitness of Influenza B Viruses with Neuraminidase Inhibitor-Resistant Substitutions in a Coinfection Model of the Human Airway Epithelium

    Science.gov (United States)

    Burnham, Andrew J.; Armstrong, Jianling; Lowen, Anice C.; Webster, Robert G.

    2015-01-01

    ABSTRACT Influenza A and B viruses are human pathogens that are regarded to cause almost equally significant disease burdens. Neuraminidase (NA) inhibitors (NAIs) are the only class of drugs available to treat influenza A and B virus infections, so the development of NAI-resistant viruses with superior fitness is a public health concern. The fitness of NAI-resistant influenza B viruses has not been widely studied. Here we examined the replicative capacity and relative fitness in normal human bronchial epithelial (NHBE) cells of recombinant influenza B/Yamanashi/166/1998 viruses containing a single amino acid substitution in NA generated by reverse genetics (rg) that is associated with NAI resistance. The replication in NHBE cells of viruses with reduced inhibition by oseltamivir (recombinant virus with the E119A mutation generated by reverse genetics [rg-E119A], rg-D198E, rg-I222T, rg-H274Y, rg-N294S, and rg-R371K, N2 numbering) or zanamivir (rg-E119A and rg-R371K) failed to be inhibited by the presence of the respective NAI. In a fluorescence-based assay, detection of rg-E119A was easily masked by the presence of NAI-susceptible virus. We coinfected NHBE cells with NAI-susceptible and -resistant viruses and used next-generation deep sequencing to reveal the order of relative fitness compared to that of recombinant wild-type (WT) virus generated by reverse genetics (rg-WT): rg-H274Y > rg-WT > rg-I222T > rg-N294S > rg-D198E > rg-E119A ≫ rg-R371K. Based on the lack of attenuated replication of rg-E119A in NHBE cells in the presence of oseltamivir or zanamivir and the fitness advantage of rg-H274Y over rg-WT, we emphasize the importance of these substitutions in the NA glycoprotein. Human infections with influenza B viruses carrying the E119A or H274Y substitution could limit the therapeutic options for those infected; the emergence of such viruses should be closely monitored. IMPORTANCE Influenza B viruses are important human respiratory pathogens contributing to a

  2. Computer viruses

    Science.gov (United States)

    Denning, Peter J.

    1988-01-01

    The worm, Trojan horse, bacterium, and virus are destructive programs that attack information stored in a computer's memory. Virus programs, which propagate by incorporating copies of themselves into other programs, are a growing menace in the late-1980s world of unprotected, networked workstations and personal computers. Limited immunity is offered by memory protection hardware, digitally authenticated object programs,and antibody programs that kill specific viruses. Additional immunity can be gained from the practice of digital hygiene, primarily the refusal to use software from untrusted sources. Full immunity requires attention in a social dimension, the accountability of programmers.

  3. Synonymous Virus Genome Recoding as a Tool to Impact Viral Fitness.

    Science.gov (United States)

    Martínez, Miguel Angel; Jordan-Paiz, Ana; Franco, Sandra; Nevot, Maria

    2016-02-01

    Synthetic genome recoding is a novel method of generating viruses with altered phenotypes, whereby many synonymous mutations are introduced into the protein coding region of the virus genome without altering the encoded proteins. Virus genome recoding with large numbers of slightly deleterious mutations has produced attenuated forms of several RNA viruses. Virus genome recoding can also aid in investigating virus interactions with innate immune responses, identifying functional virus genome structures, strategically ameliorating cis-inhibitory signaling sequences related to complex viral functions, to unravel the relevance of codon usage for the temporal regulation of viral gene expression and improving our knowledge of virus mutational robustness and adaptability. The present review discusses the impacts of synonymous genome recoding with regard to expanding our comprehension of virus biology, and the development of new and better therapeutic strategies.

  4. Dengue virus vaccine development.

    Science.gov (United States)

    Yauch, Lauren E; Shresta, Sujan

    2014-01-01

    Dengue virus (DENV) is a significant cause of morbidity and mortality in tropical and subtropical regions, causing hundreds of millions of infections each year. Infections range from asymptomatic to a self-limited febrile illness, dengue fever (DF), to the life-threatening dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS). The expanding of the habitat of DENV-transmitting mosquitoes has resulted in dramatic increases in the number of cases over the past 50 years, and recent outbreaks have occurred in the United States. Developing a dengue vaccine is a global health priority. DENV vaccine development is challenging due to the existence of four serotypes of the virus (DENV1-4), which a vaccine must protect against. Additionally, the adaptive immune response to DENV may be both protective and pathogenic upon subsequent infection, and the precise features of protective versus pathogenic immune responses to DENV are unknown, complicating vaccine development. Numerous vaccine candidates, including live attenuated, inactivated, recombinant subunit, DNA, and viral vectored vaccines, are in various stages of clinical development, from preclinical to phase 3. This review will discuss the adaptive immune response to DENV, dengue vaccine challenges, animal models used to test dengue vaccine candidates, and historical and current dengue vaccine approaches.

  5. Npro of classical swine fever virus contributes to pathogenicity in pigs by preventing type I interferon induction at local replication sites.

    Science.gov (United States)

    Tamura, Tomokazu; Nagashima, Naofumi; Ruggli, Nicolas; Summerfield, Artur; Kida, Hiroshi; Sakoda, Yoshihiro

    2014-04-17

    Classical swine fever (CSF) caused by CSF virus (CSFV) is a highly contagious disease of pigs. The viral protein Npro of CSFV interferes with alpha- and beta-interferon (IFN-α/β) induction by promoting the degradation of interferon regulatory factor 3 (IRF3). During the establishment of the live attenuated CSF vaccine strain GPE-, Npro acquired a mutation that abolished its capacity to bind and degrade IRF3, rendering it unable to prevent IFN-α/β induction. In a previous study, we showed that the GPE- vaccine virus became pathogenic after forced serial passages in pigs, which was attributed to the amino acid substitutions T830A in the viral proteins E2 and V2475A and A2563V in NS4B. Interestingly, during the re-adaptation of the GPE- vaccine virus in pigs, the IRF3-degrading function of Npro was not recovered. Therefore, we examined whether restoring the ability of Npro to block IFN-α/β induction of both the avirulent and moderately virulent GPE--derived virus would enhance pathogenicity in pigs. Viruses carrying the N136D substitution in Npro regained the ability to degrade IRF3 and suppress IFN-α/β induction in vitro. In pigs, functional Npro significantly reduced the local IFN-α mRNA expression in lymphoid organs while it increased quantities of IFN-α/β in the circulation, and enhanced pathogenicity of the moderately virulent virus. In conclusion, the present study demonstrates that functional Npro influences the innate immune response at local sites of virus replication in pigs and contributes to pathogenicity of CSFV in synergy with viral replication.

  6. Dual miRNA targeting restricts host range and attenuates neurovirulence of flaviviruses.

    Directory of Open Access Journals (Sweden)

    Konstantin A Tsetsarkin

    2015-04-01

    Full Text Available Mosquito-borne flaviviruses are among the most significant arboviral pathogens worldwide. Vaccinations and mosquito population control programs remain the most reliable means for flavivirus disease prevention, and live attenuated viruses remain one of the most attractive flavivirus vaccine platforms. Some live attenuated viruses are capable of infecting principle mosquito vectors, as demonstrated in the laboratory, which in combination with their intrinsic genetic instability could potentially lead to a vaccine virus reversion back to wild-type in nature, followed by introduction and dissemination of potentially dangerous viral strains into new geographic locations. To mitigate this risk we developed a microRNA-targeting approach that selectively restricts replication of flavivirus in the mosquito host. Introduction of sequences complementary to a mosquito-specific mir-184 and mir-275 miRNAs individually or in combination into the 3'NCR and/or ORF region resulted in selective restriction of dengue type 4 virus (DEN4 replication in mosquito cell lines and adult Aedes mosquitos. Moreover a combined targeting of DEN4 genome with mosquito-specific and vertebrate CNS-specific mir-124 miRNA can silence viral replication in two evolutionally distant biological systems: mosquitoes and mouse brains. Thus, this approach can reinforce the safety of newly developed or existing vaccines for use in humans and could provide an additional level of biosafety for laboratories using viruses with altered pathogenic or transmissibility characteristics.

  7. A Brazilian glycoprotein E-negative bovine herpesvirus type 1.2a (BHV-1.2a mutant is attenuated for cattle and induces protection against wild-type virus challenge Um mutante gE-negativo de herpesvírus bovino tipo 1.2a é atenuado para bovinos e induz proteção frente ao desafio com vírus de campo

    Directory of Open Access Journals (Sweden)

    Ana Cláudia Franco

    2002-10-01

    Full Text Available The authors previously reported the construction of a glycoprotein E-deleted (gE- mutant of bovine herpesvirus type 1.2a (BHV-1.2a. This mutant, 265gE-, was designed as a vaccinal strain for differential vaccines, allowing the distinction between vaccinated and naturally infected cattle. In order to determine the safety and efficacy of this candidate vaccine virus, a group of calves was inoculated with 265gE-. The virus was detected in secretions of inoculated calves to lower titres and for a shorter period than the parental virus inoculated in control calves. Twenty one days after inoculation, the calves were challenged with the wild type parental virus. Only mild signs of infection were detected on vaccinated calves, whereas non-vaccinated controls displayed intense rhinotracheitis and shed virus for longer and to higher titres than vaccinated calves. Six months after vaccination, both vaccinated and control groups were subjected to reactivation of potentially latent virus. The mutant 265gE- could not be reactivated from vaccinated calves. The clinical signs observed, following the reactivation of the parental virus, were again much milder on vaccinated than on non-vaccinated calves. Moreover, parental virus shedding was considerably reduced on vaccinated calves at reactivation. In view of its attenuation, immunogenicity and protective effect upon challenge and reactivation with a virulent BHV-1, the mutant 265gE- was shown to be suitable for use as a BHV-1 differential vaccine virus.Em estudo prévio os autores reportaram a construção de um mutante do Vírus da Rinotraqueíte Infecciosa Bovina (IBR ou Herpesvírus Bovino tipo 1.2a (BHV-1.2a, do qual foi deletado o gene que codifica a glicoproteina E. Esse mutante (265gE- foi construído a partir de uma amostra autóctone do vírus, tendo como objetivo seu uso como amostra vacinal em vacinas diferenciais, capazes de permitir a diferenciação entre animais vacinados e infectados com v

  8. Memantine Attenuates Alzheimer's Disease-Like Pathology and Cognitive Impairment.

    Directory of Open Access Journals (Sweden)

    Xiaochuan Wang

    Full Text Available Deficiency of protein phosphatase-2A is a key event in Alzheimer's disease. An endogenous inhibitor of protein phosphatase-2A, inhibitor-1, I1PP2A, which inhibits the phosphatase activity by interacting with its catalytic subunit protein phosphatase-2Ac, is known to be upregulated in Alzheimer's disease brain. In the present study, we overexpressed I1PP2A by intracerebroventricular injection with adeno-associated virus vector-1-I1PP2A in Wistar rats. The I1PP2A rats showed a decrease in brain protein phosphatase-2A activity, abnormal hyperphosphorylation of tau, neurodegeneration, an increase in the level of activated glycogen synthase kinase-3beta, enhanced expression of intraneuronal amyloid-beta and spatial reference memory deficit; littermates treated identically but with vector only, i.e., adeno-associated virus vector-1-enhanced GFP, served as a control. Treatment with memantine, a noncompetitive NMDA receptor antagonist which is an approved drug for treatment of Alzheimer's disease, rescued protein phosphatase-2A activity by decreasing its demethylation at Leu309 selectively and attenuated Alzheimer's disease-like pathology and cognitive impairment in adeno-associated virus vector-1-I1PP2A rats. These findings provide new clues into the possible mechanism of the beneficial therapeutic effect of memantine in Alzheimer's disease patients.

  9. Zika Virus

    Science.gov (United States)

    ... partners in government, academia, and the pharmaceutical and biotechnology industries to better understand Zika virus, the disease ... Associated Co-Infections Allergy, Immunology, Transplantation Research Resources Microbiology and Infectious Diseases Resources Preclinical and Clinical Services ...

  10. Next generation sequencing of DNA-launched Chikungunya vaccine virus

    Energy Technology Data Exchange (ETDEWEB)

    Hidajat, Rachmat; Nickols, Brian [Medigen, Inc., 8420 Gas House Pike, Suite S, Frederick, MD 21701 (United States); Forrester, Naomi [Institute for Human Infections and Immunity, Sealy Center for Vaccine Development and Department of Pathology, University of Texas Medical Branch, GNL, 301 University Blvd., Galveston, TX 77555 (United States); Tretyakova, Irina [Medigen, Inc., 8420 Gas House Pike, Suite S, Frederick, MD 21701 (United States); Weaver, Scott [Institute for Human Infections and Immunity, Sealy Center for Vaccine Development and Department of Pathology, University of Texas Medical Branch, GNL, 301 University Blvd., Galveston, TX 77555 (United States); Pushko, Peter, E-mail: ppushko@medigen-usa.com [Medigen, Inc., 8420 Gas House Pike, Suite S, Frederick, MD 21701 (United States)

    2016-03-15

    Chikungunya virus (CHIKV) represents a pandemic threat with no approved vaccine available. Recently, we described a novel vaccination strategy based on iDNA® infectious clone designed to launch a live-attenuated CHIKV vaccine from plasmid DNA in vitro or in vivo. As a proof of concept, we prepared iDNA plasmid pCHIKV-7 encoding the full-length cDNA of the 181/25 vaccine. The DNA-launched CHIKV-7 virus was prepared and compared to the 181/25 virus. Illumina HiSeq2000 sequencing revealed that with the exception of the 3′ untranslated region, CHIKV-7 viral RNA consistently showed a lower frequency of single-nucleotide polymorphisms than the 181/25 RNA including at the E2-12 and E2-82 residues previously identified as attenuating mutations. In the CHIKV-7, frequencies of reversions at E2-12 and E2-82 were 0.064% and 0.086%, while in the 181/25, frequencies were 0.179% and 0.133%, respectively. We conclude that the DNA-launched virus has a reduced probability of reversion mutations, thereby enhancing vaccine safety. - Highlights: • Chikungunya virus (CHIKV) is an emerging pandemic threat. • In vivo DNA-launched attenuated CHIKV is a novel vaccine technology. • DNA-launched virus was sequenced using HiSeq2000 and compared to the 181/25 virus. • DNA-launched virus has lower frequency of SNPs at E2-12 and E2-82 attenuation loci.

  11. Fatal vaccine-induced canine distemper virus infection in black-footed ferrets

    Science.gov (United States)

    Carpenter, J.W.; Appel, M.J.G.; Erickson, R.C.; Novilla, M.N.

    1976-01-01

    Four black-footed ferrets that were live-trapped in South Dakota and transported to the Patuxent Wildlife Research Center died within 21 days after vaccination with modified live canine distemper virus. Immunofluorescence, European ferret inoculation, virus isolation attempts, and serum-neutralization tests indicated insufficient attenuation of the vaccine for this species.

  12. The Transactivation Domain of Marek's Disease Virus (MDV) Meq Oncoprotein Does Not Affect Tumor Incidence But Plays a Role in Tumor Phenotype

    Science.gov (United States)

    Marek’s disease virus encoded oncoprotein, Meq, is responsible for the tumorigenic phenotype of the virus. We have previously shown that replacement of the meq gene in the very virulent strain Md5 with that of vaccine strain CVI988/Rispens results in virus attenuation in chickens. To determine the...

  13. Combined antiretroviral therapy attenuates hepatic extracellular matrix remodeling in HIV patients assessed by novel protein fingerprint markers

    DEFF Research Database (Denmark)

    Leeming, Diana J; Anadol, Evrim; Schierwagen, Robert

    2014-01-01

    OBJECTIVES: Combined antiretroviral therapy (cART) attenuates hepatic fibrosis in hepatitis C virus and HIV coinfected patients. However, the role of HIV or cART on hepatic fibrosis in HIV monoinfection is discussed controversially. During liver fibrosis, matrix metalloproteinases (MMPs) degrade ...

  14. Development of an acid-resistant Salmonella Typhi Ty21a attenuated vector for improved oral vaccine delivery

    Science.gov (United States)

    The licensed oral, live-attenuated bacterial vaccine for typhoid fever, Salmonella Typhi strain Ty21a, has also been utilized as a vaccine delivery platform for expression of diverse foreign antigens that stimulate protection against shigellosis, anthrax, plague, or human papilloma virus. However, T...

  15. Genetic diversity of human immunodeficiency virus type 2: evidence for distinct sequence subtypes with differences in virus biology.

    OpenAIRE

    Gao, F; Yue, L; Robertson, D L; Hill, S C; Hui, H.; Biggar, R J; Neequaye, A E; Whelan, T M; Ho, D D; Shaw, G M

    1994-01-01

    The virulence properties of human immunodeficiency virus type 2 (HIV-2) are known to vary significantly and to range from relative attenuation in certain individuals to high-level pathogenicity in others. These differences in clinical manifestations may, at least in part, be determined by genetic differences among infecting virus strains. Evaluation of the full spectrum of HIV-2 genetic diversity is thus a necessary first step towards understanding its molecular epidemiology, natural history ...

  16. Genetic diversity of human immunodeficiency virus type 2:evidence for distinct sequence subtypes with differences in virus biology

    OpenAIRE

    Gao, F; Yue, L; ROBERTSON, DL; Hill, SC; Hui, HX; BIGGAR, RJ; NEEQUAYE, AE; WHELAN, TM; Ho, DD; Shaw, GM; Sharp, Paul M.; Hahn, BH

    1994-01-01

    The virulence properties of human immunodeficiency virus type 2 (HIV-2) are known to vary significantly and to range from relative attenuation in certain individuals to high level pathogenicity in others. These differences in clinical manifestations may, at least in part, be determined by genetic differences among infecting virus strains. Evaluation of the full spectrum of HIV-2 genetic diversity is thus a necessary first step towards understanding its molecular epidemiology, natural history ...

  17. Depolarization and attenuation effects of radomes at 20 GHz

    Science.gov (United States)

    Hendrix, Charles E.; McNally, James E.; Monzingo, Robert A.

    1989-03-01

    The problem of describing the attenuation and depolarization effects of a wet radome on a transmitted signal is considered by experiments carried out with two commonly used radome materials, ESSCOLAM-6 and ESSCOLAM-8. The results suggest that a two-component model of depolarization is required to account for the observed results. Predictions for the behavior of a complete radome are obtained, but full-scale testing with an operating radome to compare predicted and actual results remains to be done. An important conclusion is that, while highly water-repellent radome materials are desirable from the point of view of attenuation, they are not so desirable in terms of the degree of depolarization introduced between orthogonally polarized signal components in frequency-reuse systems.

  18. 8 People Infected in Rare U.S. Outbreak of Rat Virus

    Science.gov (United States)

    ... Prevention. Seoul virus is a member of the Hantavirus family of rodent-borne viruses and is carried ... MedlinePlus Health Topics Animal Diseases and Your Health Hantavirus Infections About MedlinePlus Site Map FAQs Customer Support ...

  19. Efficient Approaches for Designing Fault Tolerant Reversible Carry Look-Ahead and Carry-Skip Adders

    CERN Document Server

    Islam, Md Saiful; begum, Zerina; Hafiz, Mohd Zulfiquar

    2010-01-01

    Combinational or Classical logic circuits dissipate heat for every bit of information that is lost. Information is lost when the input vector cannot be recovered from its corresponding output vector. Reversible logic circuit implements only the functions having one-to-one mapping between its input and output vectors and therefore naturally takes care of heating. Reversible logic design becomes one of the promising research directions in low power dissipating circuit design in the past few years and has found its application in low power CMOS design, digital signal processing and nanotechnology. This paper presents the efficient approaches for designing fault tolerant reversible fast adders that implement carry look-ahead and carry-skip logic. The proposed high speed reversible adders include MIG gates for the realization of its basic building block. The MIG gate is universal and parity preserving. It allows any fault that affects no more than a single signal readily detectable at the circuit's primary outputs...

  20. Imaging Rayleigh wave attenuation with USArray

    Science.gov (United States)

    Bao, Xueyang; Dalton, Colleen A.; Jin, Ge; Gaherty, James B.; Shen, Yang

    2016-07-01

    The EarthScope USArray provides an opportunity to obtain detailed images of the continental upper mantle at an unprecedented scale. The majority of mantle models derived from USArray data to date contain spatial variations in seismic-wave speed; however, in many cases these data sets do not by themselves allow a non-unique interpretation. Joint interpretation of seismic attenuation and velocity models can improve upon the interpretations based only on velocity and provide important constraints on the temperature, composition, melt content, and volatile content of the mantle. The surface wave amplitudes that constrain upper-mantle attenuation are sensitive to factors in addition to attenuation, including the earthquake source excitation, focusing and defocusing by elastic structure, and local site amplification. Because of the difficulty of isolating attenuation from these other factors, little is known about the attenuation structure of the North American upper mantle. In this study, Rayleigh wave traveltime and amplitude in the period range 25-100 s are measured using an interstation cross-correlation technique, which takes advantage of waveform similarity at nearby stations. Several estimates of Rayleigh wave attenuation and site amplification are generated at each period, using different approaches to separate the effects of attenuation and local site amplification on amplitude. It is assumed that focusing and defocusing effects can be described by the Laplacian of the traveltime field. All approaches identify the same large-scale patterns in attenuation, including areas where the attenuation values are likely contaminated by unmodelled focusing and defocusing effects. Regionally averaged attenuation maps are constructed after removal of the contaminated attenuation values, and the variations in intrinsic shear attenuation that are suggested by these Rayleigh wave attenuation maps are explored.

  1. Molecular genetics of DNA viruses: recombinant virus technology.

    Science.gov (United States)

    Neuhierl, Bernhard; Delecluse, Henri-Jacques

    2005-01-01

    Recombinant viral genomes cloned onto BAC vectors can be subjected to extensive molecular genetic analysis in the context of E. coli. Thus, the recombinant virus technology exploits the power of prokaryotic genetics to introduce all kinds of mutations into the recombinant genome. All available techniques are based on homologous recombination between a targeting vector carrying the mutated version of the gene of interest and the recombinant virus. After modification, the mutant viral genome is stably introduced into eukaryotic cells permissive for viral lytic replication. In these cells, mutant viral genomes can be packaged into infectious particles to evaluate the effect of these mutations in the context of the complete genome.

  2. Recent advances in vaccine development for herpes simplex virus types I and II

    OpenAIRE

    Coleman, Jeffrey L.; Shukla, Deepak

    2013-01-01

    Despite recent advances in vaccine design and strategies, latent infection with herpes simplex virus (HSV) remains a formidable challenge. Approaches involving live-attenuated viruses and inactivated viral preparations were popular throughout the twentieth century. In the past ten years, many vaccine types, both prophylactic or therapeutic, have contained a replication-defective HSV, viral DNA or glycoproteins. New research focused on the mechanism of immune evasion by the virus has involved ...

  3. Computer Viruses. Technology Update.

    Science.gov (United States)

    Ponder, Tim, Comp.; Ropog, Marty, Comp.; Keating, Joseph, Comp.

    This document provides general information on computer viruses, how to help protect a computer network from them, measures to take if a computer becomes infected. Highlights include the origins of computer viruses; virus contraction; a description of some common virus types (File Virus, Boot Sector/Partition Table Viruses, Trojan Horses, and…

  4. SEISMIC ATTENUATION FOR RESERVOIR CHARACTERIZATION

    Energy Technology Data Exchange (ETDEWEB)

    Joel Walls; M.T. Taner; Naum Derzhi; Gary Mavko; Jack Dvorkin

    2003-12-01

    We have developed and tested technology for a new type of direct hydrocarbon detection. The method uses inelastic rock properties to greatly enhance the sensitivity of surface seismic methods to the presence of oil and gas saturation. These methods include use of energy absorption, dispersion, and attenuation (Q) along with traditional seismic attributes like velocity, impedance, and AVO. Our approach is to combine three elements: (1) a synthesis of the latest rock physics understanding of how rock inelasticity is related to rock type, pore fluid types, and pore microstructure, (2) synthetic seismic modeling that will help identify the relative contributions of scattering and intrinsic inelasticity to apparent Q attributes, and (3) robust algorithms that extract relative wave attenuation attributes from seismic data. This project provides: (1) Additional petrophysical insight from acquired data; (2) Increased understanding of rock and fluid properties; (3) New techniques to measure reservoir properties that are not currently available; and (4) Provide tools to more accurately describe the reservoir and predict oil location and volumes. These methodologies will improve the industry's ability to predict and quantify oil and gas saturation distribution, and to apply this information through geologic models to enhance reservoir simulation. We have applied for two separate patents relating to work that was completed as part of this project.

  5. Magnetoelectric Composite Based Microwave Attenuator

    Science.gov (United States)

    Tatarenko, A. S.; Srinivasan, G.

    2005-03-01

    Ferrite-ferroelectric composites are magnetoelectric (ME) due to their response to elastic and electromagnetic force fields. The ME composites are characterized by tensor permittivity, permeability and ME susceptibility. The unique combination of magnetic, electrical, and ME interactions, therefore, opens up the possibility of electric field tunable ferromagnetic resonance (FMR) based devices [1]. Here we discuss an ME attenuator operating at 9.3 GHz based on FMR in a layered sample consisting of lead magnesium niobate-lead titanate bonded to yttrium iron garnet (YIG) film on a gadolinium gallium garnet substrate. Electrical tuning is realized with the application of a control voltage due to ME effect; the shift is 0-15 Oe as E is increased from 0 to 3 kV/cm. If the attenuator is operated at FMR, the corresponding insertion loss will range from 25 dB to 2 dB. 1. S. Shastry and G. Srinivasan, M.I. Bichurin, V.M. Petrov, A.S. Tatarenko. Phys. Rev. B, 70 064416 (2004). - supported by grants the grants from the National Science Foundation (DMR-0302254), from Russian Ministry of Education (Å02-3.4-278) and from Universities of Russia Foundation (UNR 01.01.026).

  6. The human immunodeficiency virus type 1 envelope confers higher rates of replicative fitness to perinatally transmitted viruses than to nontransmitted viruses.

    Science.gov (United States)

    Kong, Xiaohong; West, John T; Zhang, Hong; Shea, Danielle M; M'soka, Tendai J; Wood, Charles

    2008-12-01

    Selection of a minor viral genotype during perinatal transmission of human Immunodeficiency virus type 1 (HIV-1) has been observed, but there is a lack of information on the correlation of the restrictive transmission with biological properties of the virus, such as replicative fitness. Recombinant viruses expressing the enhanced green fluorescent protein or the Discosoma sp. red fluorescent (DsRed2) protein carrying the V1 to V5 regions of env from seven mother-infant pairs (MIPs) infected by subtype C HIV-1 were constructed, and competition assays were carried out to compare the fitness between the transmitted and nontransmitted viruses. Flow cytometry was used to quantify the frequency of infected cells, and the replicative fitness was determined based on a calculation that takes into account replication of competing viruses in a single infection versus dual infections. Transmitted viruses from five MIPs with the mothers chronically infected showed a restrictive env genotype, and all the recombinant viruses carrying the infants' Env had higher replicative fitness than those carrying the Env from the mothers. This growth fitness is lineage specific and can be observed only within the same MIP. In contrast, in two MIPs where the mothers had undergone recent acute infection, the viral Env sequences were similar between the mothers and infants and showed no further restriction in quasispecies during perinatal transmission. The recombinant viruses carrying the Env from the infants' viruses also showed replication fitness similar to those carrying the mothers' Env proteins. Our results suggest that newly transmitted viruses from chronically infected mothers have been selected to have higher replicative fitness to favor transmission, and this advantage is conferred by the V1 to V5 region of Env of the transmitted viruses. This finding has important implications for vaccine design or development of strategies to prevent HIV-1 transmission.

  7. Detailed Study of Seismic Wave Attenuation in Carbonate Rocks: Application on Abu Dhabi Oil Fields

    Science.gov (United States)

    Bouchaala, F.; Ali, M. Y.; Matsushima, J.

    2015-12-01

    Seismic wave attenuation is a promising attribute for the petroleum exploration, thanks to its high sensitivity to physical properties of subsurface. It can be used to enhance the seismic imaging and improve the geophysical interpretation which is crucial for reservoir characterization. However getting an accurate attenuation profile is not an easy task, this is due to complex mechanism of this parameter, although that many studies were carried out to understand it. The degree of difficulty increases for the media composed of carbonate rocks, known to be highly heterogeneous and with complex lithology. That is why few attenuation studies were done successfully in carbonate rocks. The main objectives of this study are, Getting an accurate and high resolution attenuation profiles from several oil fields. The resolution is very important target for us, because many reservoirs in Abu Dhabi oil fields are tight.Separation between different modes of wave attenuation (scattering and intrinsic attenuations).Correlation between the attenuation profiles and other logs (Porosity, resistivity, oil saturation…), in order to establish a relationship which can be used to detect the reservoir properties from the attenuation profiles.Comparison of attenuation estimated from VSP and sonic waveforms. Provide spatial distribution of attenuation in Abu Dhabi oil fields.To reach these objectives we implemented a robust processing flow and new methodology to estimate the attenuation from the downgoing waves of the compressional VSP data and waveforms acquired from several wells drilled in Abu Dhabi. The subsurface geology of this area is primarily composed of carbonate rocks and it is known to be highly fractured which complicates more the situation, then we separated successfully the intrinsic attenuation from the scattering. The results show that the scattering is significant and cannot be ignored. We found also a very interesting correlation between the attenuation profiles and the

  8. Novel chikungunya vaccine candidate with an IRES-based attenuation and host range alteration mechanism.

    Directory of Open Access Journals (Sweden)

    Kenneth Plante

    2011-07-01

    Full Text Available Chikungunya virus (CHIKV is a reemerging mosquito-borne pathogen that has recently caused devastating urban epidemics of severe and sometimes chronic arthralgia. As with most other mosquito-borne viral diseases, control relies on reducing mosquito populations and their contact with people, which has been ineffective in most locations. Therefore, vaccines remain the best strategy to prevent most vector-borne diseases. Ideally, vaccines for diseases of resource-limited countries should combine low cost and single dose efficacy, yet induce rapid and long-lived immunity with negligible risk of serious adverse reactions. To develop such a vaccine to protect against chikungunya fever, we employed a rational attenuation mechanism that also prevents the infection of mosquito vectors. The internal ribosome entry site (IRES from encephalomyocarditis virus replaced the subgenomic promoter in a cDNA CHIKV clone, thus altering the levels and host-specific mechanism of structural protein gene expression. Testing in both normal outbred and interferon response-defective mice indicated that the new vaccine candidate is highly attenuated, immunogenic and efficacious after a single dose. Furthermore, it is incapable of replicating in mosquito cells or infecting mosquitoes in vivo. This IRES-based attenuation platform technology may be useful for the predictable attenuation of any alphavirus.

  9. Attenuation map reconstruction from TOF PET data

    CERN Document Server

    Yang, Qingsong; Wang, Ge

    2013-01-01

    To reconstruct a radioactive tracer distribution with positron emission tomography (PET), the background attenuation correction is needed to eliminate image artifacts. Recent research shows that time-of-flight (TOF) PET data determine the attenuation sinogram up to a constant, and its gradient can be computed using an analytic algorithm. In this paper, we study a direct estimation of the sinogram only from TOF PET data. First, the gradient of the attenuation sinogram is estimated using the aforementioned algorithm. Then, a relationship is established to link the differential attenuation sinogram and the underlying attenuation background. Finally, an iterative algorithm is designed to determine the attenuation sinogram accurately and stably. A 2D numerical simulation study is conducted to verify the correctness of our proposed approach.

  10. Fault tolerant reversible logic synthesis: Carry look-ahead and carry-skip adders

    CERN Document Server

    Islam, Md Saiful; Begum, Zerina; Hafiz, Mohd Zulfiquar; 10.1109/ACTEA.2009.5227871

    2010-01-01

    Irreversible logic circuits dissipate heat for every bit of information that is lost. Information is lost when the input vector cannot be recovered from its corresponding output vector. Reversible logic circuit naturally takes care of heating because it implements only the functions that have one-to-one mapping between its input and output vectors. Therefore reversible logic design becomes one of the promising research directions in low power dissipating circuit design in the past few years and has found its application in low power CMOS design, digital signal processing and nanotechnology. This paper presents the efficient approaches for designing reversible fast adders that implement carry look-ahead and carry-skip logic. The proposed 16-bit high speed reversible adder will include IG gates for the realization of its basic building block. The IG gate is universal in the sense that it can be used to synthesize any arbitrary Boolean-functions. The IG gate is parity preserving, that is, the parity of the input...

  11. Optimal ultrasonic array focusing in attenuative media.

    Science.gov (United States)

    Ganguli, A; Gao, R X; Liang, K; Jundt, J

    2011-12-01

    This paper presents a parametric study on the efficiency of ultrasound focusing in an attenuative medium, using phased arrays. Specifically, an analytical model of ultrasound wave focusing in a homogeneous, isotropic and attenuative fluid with point sources is presented. Calculations based on the model have shown that in an attenuative medium, an optimum frequency exists for the best focusing performance for a particular size of aperture and focal distance. The effect of different f numbers on the focusing performance in the attenuative medium is further investigated. The information obtained from the analytical model provides insights into the design and installation of a phased transducer array for energy efficient wave focusing.

  12. Genotypic lineages and restriction fragment length polymorphism of canine distemper virus isolates in Thailand.

    Science.gov (United States)

    Radtanakatikanon, Araya; Keawcharoen, Juthatip; Charoenvisal, Na Taya; Poovorawan, Yong; Prompetchara, Eakachai; Yamaguchi, Ryoji; Techangamsuwan, Somporn

    2013-09-27

    Canine distemper virus (CDV) is known to cause multisystemic disease in all families of terrestrial carnivores. Attenuated live vaccines have been used to control CDV in a variety of species for many decades, yet a number of CDV infections in vaccinated dogs are still observed. The aims of this study were to investigate the genetic diversity of CDV lineages based on phosphoprotein (P), hemagglutinin (H) and fusion protein (F) genes and to develop the restriction fragment length polymorphism (RFLP) technique for effective differentiation among individual wild-type and vaccine lineages in Thailand. Four commercial vaccine products, thirteen conjunctival swabs and various tissues from 9 necropsied dogs suspected of having CDV infections were included. Virus isolation was performed using Vero cell expressing canine signaling lymphocyte activation molecules (Vero-DST cells). Reverse-transcription polymerase chain reaction (RT-PCR) on 3 gene regions from the dog derived specimens and the vaccines were carried out, then RFLP analysis upon F-gene amplified fragments was developed. Nucleotide sequence and phylogenetic analysis were compared with other CDV lineages in Genbank. Phylogenetic relationships revealed that CDV field isolates were separated from the vaccine lineage and could be divided into two clusters; one of which belonged to the Asia-1 lineage and another, not related to any previous recognized lineages was proposed as 'Asia-4'. RFLP patterns demonstrating concordance with phylogenetic trees of the distemper virus allowed for differentiation between the Asia-1, Asia-4 and vaccine lineages. Thus, RFLP technique is able to effectively distinguish individual wild-type canine distemper virus from vaccine lineages in Thailand.

  13. Attenuation of Dengue Virus Infection by Adeno-Associated Virus-Mediated siRNA Delivery

    Science.gov (United States)

    2004-08-09

    safe and efficacious in Phase I clinical trials for gene therapy of cystic fibrosis and hemophilia B and are regarded as a potential alternative to...retroviral and adenoviral vectors for gene therapy in humans. The AAV vectors have a number of advantages over other vectors. They are not pathogenic and...did not induce significant acute inflammatory responses and, therefore, is useful in gene therapy for DEN infection in humans. In conclusion, we

  14. Complete Genome Sequence of Rift Valley Fever Virus Strain Lunyo.

    Science.gov (United States)

    Lumley, Sarah; Horton, Daniel L; Marston, Denise A; Johnson, Nicholas; Ellis, Richard J; Fooks, Anthony R; Hewson, Roger

    2016-04-14

    Using next-generation sequencing technologies, the first complete genome sequence of Rift Valley fever virus strain Lunyo is reported here. Originally reported as an attenuated antigenic variant strain from Uganda, genomic sequence analysis shows that Lunyo clusters together with other Ugandan isolates.

  15. Live attenuated varicella vaccine use in immunocompromised children and adults.

    Science.gov (United States)

    Gershon, A A; Steinberg, S P; Gelb, L

    1986-10-01

    Live attenuated varicella vaccine has been administered to 307 children with leukemia in remission and to 86 healthy adults. The vaccine was well tolerated and immunogenic. The major side effect in leukemic children receiving maintenance chemotherapy was development of a vaccine-associated rash. Vaccinees in whom a rash developed were potentially somewhat infectious to others about 1 month after immunization. Vaccination was not associated with an increase in the incidence of herpes zoster or in relapse of leukemia. Vaccination provided excellent protection against severe varicella. It was associated with a significant decrease in the attack rate of chickenpox following an intimate exposure to varicella-zoster virus, conferring about 80% protection in leukemic children. The cases of breakthrough varicella that occurred were mild. Thus, the vaccine may either prevent or modify varicella in high-risk individuals. It may also have use for prevention of nosocomial varicella.

  16. Wideband, 50 dB Attenuation Range Liquid Crystal Based Variable Optical Attenuator

    Institute of Scientific and Technical Information of China (English)

    J.J.; Pan; Henry; He; Eric; Zhang

    2003-01-01

    A compact variable optical attenuator, covering C and L bands with over 50 dB attenuation range, is realized using a single liquid crystal cell with a tilted fused silica coating compensating the cell's small residual birefringence.

  17. [Recent Advances in Vaccines and Drugs Against the Ebola Virus].

    Science.gov (United States)

    Zhu, Xiang; Yao, Chenguang; Wei, Yanhong; Kou, Zheng; Hu, Kanghong

    2015-05-01

    The Ebola virus belongs to the Filovirus family, which causes Ebola hemorrhagic fever (mortality, 25%-90%). An outbreak of infection by the Ebola virus is sweeping across West Africa, leading to high mortality and worldwide panic. The Ebola virus has caused a serious threat to public health, so intensive scientific studies have been carried out. Several vaccines (e.g., rVSV-ZEBOV, ChAd3-ZEBOV) have been put into clinical trials and antiviral drugs (e.g., TKM-Ebola, ZMAPP) have been administered in the emergency setting to patients infected by the Ebola virus. Here, recent advances in vaccines and drugs against the Ebola virus are reviewed.

  18. Ultrasonic attenuation in cuprate superconductors

    Indian Academy of Sciences (India)

    T Gupta; D M Gaitonde

    2002-05-01

    We calculate the longitudinal ultrasonic attenuation rate (UAR) in clean d-wave superconductors in the Meissner and the mixed phases. In the Meissner phase we calculate the contribution of previously ignored processes involving the excitation of a pair of quasi-holes or quasi-particles. There is a contribution ∝ in the regime B ≪ F ≪ 0 and a contribution ∝ 1/ in the regime F ≪ B ≪ 0. We find that these contributions to the UAR are large and cannot be ignored. In the mixed phase, using a semi-classical description, we calculate the electronic quasi-particle contribution to the UAR which at very low , has a independent term proportional to $\\sqrt{H}$.

  19. Vaccines in Development against West Nile Virus

    Directory of Open Access Journals (Sweden)

    Frederic Tangy

    2013-09-01

    Full Text Available West Nile encephalitis emerged in 1999 in the United States, then rapidly spread through the North American continent causing severe disease in human and horses. Since then, outbreaks appeared in Europe, and in 2012, the United States experienced a new severe outbreak reporting a total of 5,387 cases of West Nile virus (WNV disease in humans, including 243 deaths. So far, no human vaccine is available to control new WNV outbreaks and to avoid worldwide spreading. In this review, we discuss the state-of-the-art of West Nile vaccine development and the potential of a novel safe and effective approach based on recombinant live attenuated measles virus (MV vaccine. MV vaccine is a live attenuated negative-stranded RNA virus proven as one of the safest, most stable and effective human vaccines. We previously described a vector derived from the Schwarz MV vaccine strain that stably expresses antigens from emerging arboviruses, such as dengue, West Nile or chikungunya viruses, and is strongly immunogenic in animal models, even in the presence of MV pre-existing immunity. A single administration of a recombinant MV vaccine expressing the secreted form of WNV envelope glycoprotein elicited protective immunity in mice and non-human primates as early as two weeks after immunization, indicating its potential as a human vaccine.

  20. DSM-5: ATTENUATED PSYCHOSIS SYNDROME?

    Directory of Open Access Journals (Sweden)

    Eduardo Fonseca-Pedrero

    2013-09-01

    Full Text Available Psychotic syndrome includes several devastating mental disorders characterized by a rupture of higher mental functions. The signs and symptoms of psychosis begin in adolescence or early adulthood and usually begin gradually and progress over time. Attenuated psychosis syndrome is a new DSM-5 diagnostic proposal which deals with identifying people at high-risk mental state (ARMS/UHR which may be a predictor of conversion to psychosis. The potential benefit would be that if psychotic disorder is treated more effectively in its early stages, it could produce a lasting beneficial effect that probably could not be achieved with later intervention. This syndrome has generated intense discussion in specialized scientific and professional forums, crisscrossing arguments in favor and against its inclusion. HRMS is preferentially evaluated in the adolescent or young adult population. HRMS evolution is associated with a higher rate of transition toward nonaffective psychosis, although it can evolve toward other mental disorders, remain stable or remit over time. Empirical evidence shows that early intervention seems to have a certain beneficial effect, although for now the results are still insufficient and contradictory. The lack of specificity of symptoms in predicting psychosis, presence of certain limitations (e.g., stigmatization, results found in early interventions and lack of empirical evidence, have led to include the attenuated psychosis syndrome in the DSM-5 Appendix III. The main benefits and limitations of including this supposed category, possible lessons learned from this type of study and future lines of action are discussed in the light of these findings.

  1. Attenuation characteristics of a light attenuator combined by polarizers with different extinction ratios

    Institute of Scientific and Technical Information of China (English)

    Huang Chong; Deng Peng; Zhao Shuang; Chen Hai-Qing

    2011-01-01

    This paper deals with a systematical analysis and an algorithm of attenuation characteristics of a light attenuator combined by n pieces of polarizers(n-LACP)whose extinction ratios are different from each other.The attenuation ratio expression of a two-LACP is deduced. We find that the monotonic attenuation interval depends on the first polarizer and that the attenuation range depends on the second one.For the three-LACP,a method for obtaining a monotonic attenuation interval is proposed.Moreover,the attenuation ratio expression is demonstrated.Analysis and experiment show that when the initial status of the three-LACP is at the maximum output,if the second or third polarizer rotates alone,the minimum attenuation ratios can reach K2-1and K3-1,respectively,and if the first polarizer rotates,a minimum attenuation ratio of K2-1K3-1can be obtained(K1,K2 and K3 represent the extinction ratios of the three polarizers in turn).Furthermore,the attenuation ratio expression of n-LACP and the relevant attenuation characteristics are proposed.The minimum attenuation ratio of an n-LACP is(K2K3...Kn)-1.

  2. Static tests of excess ground attenuation at Wallops Flight Center

    Science.gov (United States)

    Sutherland, L. C.; Brown, R.

    1981-01-01

    An extensive experimental measurement program which evaluated the attenuation of sound for close to horizontal propagation over the ground was designed to replicate, under static conditions, results of the flight measurements carried out earlier by NASA at the same site (Wallops Flight Center). The program consisted of a total of 41 measurement runs of attenuation, in excess of spreading and air absorption losses, for one third octave bands over a frequency range of 50 to 4000 Hz. Each run consisted of measurements at 10 locations up to 675 m, from a source located at nominal elevations of 2.5, or 10 m over either a grassy surface or an adjacent asphalt concrete runway surface. The tests provided a total of over 8100 measurements of attenuation under conditions of low wind speed averaging about 1 m/s and, for most of the tests, a slightly positive temperature gradient, averaging about 0.3 C/m from 1.2 to 7 m. The results of the measurements are expected to provide useful experimental background for the further development of prediction models of near grazing incidence sound propagation losses.

  3. HoBi-like virus challenge of pregnant cows that had previously given birth to calves persistently infected with bovine viral diarrhea virus

    Science.gov (United States)

    The ability of bovine viral diarrhea viruses (BVDV) to establish persistent infection (PI) following fetal infection is central to keeping these viruses circulating. Similarly, an emerging species of pestivirus, HoBi-like viruses, is also able to establish PIs. Dams that are not PI, but carrying PI ...

  4. DISTURBANCE ATTENUATION FOR UNCERTAIN NONLINEAR CASCADED SYSTEMS

    Institute of Scientific and Technical Information of China (English)

    BI Weiping; MU Xiaowu; SUN Yuqiang

    2004-01-01

    In present paper, the disturbance attenuation problem of uncertain nonlinear cascaded systems is studied. Based on the adding one power integrator technique and recursive design, a feedback controller that solves the disturbance attenuation problem is constructed for uncertain nonlinear cascaded systems with internal stability.

  5. Attenuation coefficients for water quality trading.

    Science.gov (United States)

    Keller, Arturo A; Chen, Xiaoli; Fox, Jessica; Fulda, Matt; Dorsey, Rebecca; Seapy, Briana; Glenday, Julia; Bray, Erin

    2014-06-17

    Water quality trading has been proposed as a cost-effective approach for reducing nutrient loads through credit generation from agricultural or point source reductions sold to buyers facing costly options. We present a systematic approach to determine attenuation coefficients and their uncertainty. Using a process-based model, we determine attenuation with safety margins at many watersheds for total nitrogen (TN) and total phosphorus (TP) loads as they transport from point of load reduction to the credit buyer. TN and TP in-stream attenuation generally increases with decreasing mean river flow; smaller rivers in the modeled region of the Ohio River Basin had TN attenuation factors per km, including safety margins, of 0.19-1.6%, medium rivers of 0.14-1.2%, large rivers of 0.13-1.1%, and very large rivers of 0.04-0.42%. Attenuation in ditches transporting nutrients from farms to receiving rivers is 0.4%/km for TN, while for TP attenuation in ditches can be up to 2%/km. A 95 percentile safety margin of 30-40% for TN and 6-10% for TP, applied to the attenuation per km factors, was determined from the in-stream sensitivity of load reductions to watershed model parameters. For perspective, over 50 km a 1% per km factor would result in 50% attenuation = 2:1 trading ratio.

  6. 鼻咽癌特异性减毒重组疫苗 Lmdd-LMP2 A 的构建及其抑瘤效应的研究%Construction of Lmdd-LMP2A, an attenuated Listeria vaccine strain expressing the Epstein-Barr vi-rus latent membrane protein 2A (EBV-LMP2A) and evaluation of its anti-tumor effects against na-sopharyngeal carcinoma

    Institute of Scientific and Technical Information of China (English)

    赵玮; 陈小琴; 万昕; 程慈; 林喆; 冯东举; 姚堃; 陈云

    2015-01-01

    Objective To prepare an attenuated Listeria vaccine Lmdd-LMP2A expressing the Ep-stein-Barr virus latent membrane protein 2A ( EBV-LMP2A) and evaluate its specific anti-tumor effects on nasopharyngeal carcinoma.Methods The gene fragment encoding EBV-LMP2A was amplified by PCR analysis and then subcloned into the shuttle vector p1565.PCR restriction enzyme digestion and DNA se-quencing were performed to identify the recombinant shuttle vector p1565-LMP2A.The p1565-LMP2A vector was then transformed into competent strains of the attenuated Listeria monocytogenes ( Lmdd) .The recombi-nant attenuated Listeria vaccine strain Lmdd-LMP2A was verified by Western blot assay.The histological sections of spleen and liver tissues were stained by Haematoxylin and eosin ( H&E) for analysis of inflamma-tion.A tumor-bearing HLA-A2 transgenic mouse model was established by subcutaneous injection of CNE-1/HLA-A2/LMP2A nasopharyngeal carcinoma cell line.The prepared Lmdd-LMP2A vaccine was inoculated into the mice via tail intravenous injection for the evaluation of specific CTL induction and the in vivo anti-tumor effects.Results The shuttle vector p1565-LMP2A and the recombinant attenuated Listeria vaccine strain Lmdd-LMP2A with stable expression of LMP2A protein were successfully constructed.The immunized mice showed mild inflammations with no structural damage and necrosis as indicated by H&E staining.The growth of tumors in tumor-bearing HLA-A2 transgenic mice was significantly inhibited by the immunization of Lmdd-LMP2A vaccine as compared with mice without inoculation.The survival time of mice was prolonged with the immunization of Lmdd-LMP2A vaccine.Conclusion The prepared attenuated Listeria vaccine Lm-dd-LMP2A showed specific anti-tumor effects with the safety advantage, suggesting the possibility of using it for anti-tumor therapy in clinic.%目的:构建含有EB病毒潜伏膜蛋白2A(LMP2A)的减毒单核增生性李斯特菌重组疫苗(Lmdd-LMP2A),并检测

  7. Pichia pastoris-Expressed Dengue 2 Envelope Forms Virus-Like Particles without Pre-Membrane Protein and Induces High Titer Neutralizing Antibodies

    OpenAIRE

    Shailendra Mani; Lav Tripathi; Rajendra Raut; Poornima Tyagi; Upasana Arora; Tarani Barman; Ruchi Sood; Alka Galav; Wahala Wahala; Aravinda de Silva; Sathyamangalam Swaminathan; Navin Khanna

    2013-01-01

    Dengue is a mosquito-borne viral disease with a global prevalence. It is caused by four closely-related dengue viruses (DENVs 1-4). A dengue vaccine that can protect against all four viruses is an unmet public health need. Live attenuated vaccine development efforts have encountered unexpected interactions between the vaccine viruses, raising safety concerns. This has emphasized the need to explore non-replicating dengue vaccine options. Virus-like particles (VLPs) which can elicit robust imm...

  8. Oropuche virus: A virus present but ignored

    Directory of Open Access Journals (Sweden)

    Salim Mattar V.

    2015-09-01

    Full Text Available Bunyaviruses are RNA viruses that affect animals and plants; they have five genera and four of them affect humans: Orthobunyavirus, Nairovirus, Phlebovirus and Hantavirus. All of them are Arbovirus, except Hantavirus. The Orthobunyaviruses comprise Oropouche, Tahyna, La Crosse virus, California encephalitis virus and Heartland virus recently discovered (1. Except for Heartland virus which is transmitted by ticks of the genus Amblyoma, these Phleboviruses have as vectors mosquitoes, which bite small mammals which are able to be as reservoirs amplifiers.

  9. Ultrasound fields in an attenuating medium

    DEFF Research Database (Denmark)

    Jensen, Jørgen Arendt; Gandhi,, D; O'Brien,, W.D., Jr.

    1993-01-01

    Ultrasound fields propagating in tissue will undergo changes in shape not only due to diffraction, but also due to the frequency dependent attenuation. Linear fields can be fairly well predicted for a non-attenuating medium like water by using the Tupholme-Stepanishen method for calculating...... the spatial impulse response, whereas the field cannot readily be found for an attenuating medium. In this paper we present a simulation program capable of calculating the field in a homogeneous attenuating medium. The program splits the aperture into rectangles and uses a far-field approximation for each...... of the rectangles and sums all contributions to arrive at the spatial impulse response for the aperture and field point. This approach makes it possible to model all transducer apertures, and the program can readily calculate the emitted, pulse-echo and continuous wave field. Attenuation is included by splitting...

  10. Molecular characterization of a reassortant virus derived from Lassa and Mopeia viruses.

    Science.gov (United States)

    Moshkoff, Dmitry A; Salvato, Maria S; Lukashevich, Igor S

    2007-04-01

    In this article we describe two new complete genomic sequences of Old World Arenaviruses: the Mopeia (MOP) virus and the reassortant MOP/LAS virus, clone 29, or ML29. This reassortant has the large (L) RNA from MOP virus and the small (S) RNA from Lassa (LAS) virus, Josiah strain. Recent studies showed that the ML29 virus is not pathogenic for mice, guinea pigs, or macaques, can completely protect guinea pigs from Lassa virus, and elicit vigorous cell-mediated immunity in immunized monkeys (Lukashevich, I. S., Patterson, J., Carrion, R., Moshkoff, D., Ticer, A., Zapata, J., Brasky, K., Geiger, R., Hubbard, G. B., Bryant, J., and Salvato, M. S., J Virol 79, 13934-13942, 2005). This is a molecular characterization of a reassortant virus, which has been put forward as a live attenuated vaccine candidate against Lassa Fever. Sequence analysis of this reassortant virus revealed 5 non-conservative amino acid substitutions that distinguished it from the parental LAS and MOP viruses. Three substitutions were found outside the conserved RNA-dependent RNA polymerase (RdRp) motifs. A fourth substitution was located between the glycoprotein (GPC)-cleavage site and the putative fusion peptide of GP2. The nucleocapsid protein (NP) contained a fifth substitution in the carboxyl-terminal region of the protein. Two mutations were found within each non-coding terminus of the L segment and one mutation was located in the 3' non-coding region of the S segment of the MOP/LAS virus. ML29 mutations in its genomic termini may have implications for the genetic stability and replication efficiency of ML29 reassortant.

  11. Enteric and indicator virus removal by surface flow wetlands.

    Science.gov (United States)

    Rachmadi, Andri T; Kitajima, Masaaki; Pepper, Ian L; Gerba, Charles P

    2016-01-15

    We investigated the occurrence and attenuation of several human enteric viruses (i.e., norovirus, adenovirus, Aichi virus 1, polyomaviruses, and enterovirus) as well as a plant virus, pepper mild mottle virus (PMMoV), at two surface flow wetlands in Arizona. The retention time in one of the wetlands was seven days, whereas in the other wetland it could not be defined. Water samples were collected at the inlet and outlet from the wetlands over nine months, and concentration of viral genomes was determined by quantitative polymerase chain reaction (qPCR). Of the human enteric viruses tested, adenovirus and Aichi virus 1 were found in the greatest prevalence in treated wastewater (i.e., inlet of the wetlands). Reduction efficiencies of enteric viruses by the wetlands ranged from 1 to 3 log10. Polyomaviruses were generally removed to below detection limit, indicating at least 2 to 4 log10 removal. PMMoV was detected in a greater concentration in the inlet of both wetlands for all the viruses tested (10(4) to 10(7) genome copies/L), but exhibited little or no removal (1 log10 or less). To determine the factors associated with virus genome attenuation (as determined by qPCR), the persistence of PMMoV and poliovirus type 1 (an enterovirus) was studied in autoclaved and natural wetland water, and deionized water incubated under three different temperatures for 21 days. A combination of elevated water temperature and biological activities reduced poliovirus by 1 to 4 log10, while PMMoV was not significantly reduced during this time period. Overall, PMMoV showed much greater persistence than human viruses in the wetland treatment.

  12. Carrying Capacity of Marine Region in Liaoning Province

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Carrying capacity is one of important studies on coordinating development of population, resources, and environment. At present, the researches on it mainly concentrate on the carrying capacity for population and economy,such as the water resources carrying capacity, the land resources carrying capacity, the environment carrying capacity,etc. Based on the related theories and methods, this paper creatively proposed the concept and meaning of carrying capacity of marine region, and formed the appraisal system. According to the developing situation of marine economy of Liaoning Province in recent years, and by employing the method of the state space, this paper also measured the cartying capacity and carrying state of marine region and discussed the sustainable problems of marine economy of Liaoning. The research results show that the carrying state of marine region of Liaoning is in the state of overloading at present, but taking a favorable turn.

  13. Delay Efficient 32-Bit Carry-Skip Adder

    OpenAIRE

    Yu Shen Lin; Damu Radhakrishnan

    2008-01-01

    The design of a 32-bit carry-skip adder to achieve minimum delay is presented in this paper. A fast carry look-ahead logic using group generate and group propagate functions is used to speed up the performance of multiple stages of ripple carry adders. The group generate and group propagate functions are generated in parallel with the carry generation for each block. The optimum block sizes are decided by considering the critical path into account. The new architecture ...

  14. 46 CFR 111.105-35 - Vessels carrying coal.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Vessels carrying coal. 111.105-35 Section 111.105-35...-GENERAL REQUIREMENTS Hazardous Locations § 111.105-35 Vessels carrying coal. (a) The following are Class II, Division 1, (Zone 10 or Z) locations on a vessel that carries coal: (1) The interior of each...

  15. 49 CFR 177.870 - Regulations for passenger carrying vehicles.

    Science.gov (United States)

    2010-10-01

    ... be transported by passenger-carrying aircraft or rail car may be transported on a motor vehicle... PUBLIC HIGHWAY Regulations Applying to Hazardous Material on Motor Vehicles Carrying Passengers for Hire... authorized by parts 170-189 of this subchapter to be transported on motor vehicles carrying passengers...

  16. Interpretations of the Image of Caroline in Sister Carrie

    Institute of Scientific and Technical Information of China (English)

    钱绘

    2014-01-01

    In the history of American naturalistic literature, Sister Carrie is a representative work of this literary genre. And the protagonist of this novel Caroline has always been a controversial character. Based on Sister Carrie and the social background of that period in America, this paper discussed the various interpretations of the image of Carrie from different aspects.

  17. Early infections by myxoma virus of young rabbits (Oryctolagus cuniculus) protected by maternal antibodies activate their immune system and enhance herd immunity in wild populations.

    Science.gov (United States)

    Marchandeau, Stéphane; Pontier, Dominique; Guitton, Jean-Sébastien; Letty, Jérôme; Fouchet, David; Aubineau, Jacky; Berger, Francis; Léonard, Yves; Roobrouck, Alain; Gelfi, Jacqueline; Peralta, Brigitte; Bertagnoli, Stéphane

    2014-03-04

    The role of maternal antibodies is to protect newborns against acute early infection by pathogens. This can be achieved either by preventing any infection or by allowing attenuated infections associated with activation of the immune system, the two strategies being based on different cost/benefit ratios. We carried out an epidemiological survey of myxomatosis, which is a highly lethal infectious disease, in two distant wild populations of rabbits to describe the epidemiological pattern of the disease. Detection of specific IgM and IgG enabled us to describe the pattern of immunity. We show that maternal immunity attenuates early infection of juveniles and enables activation of their immune system. This mechanism associated with steady circulation of the myxoma virus in both populations, which induces frequent reinfections of immune rabbits, leads to the maintenance of high immunity levels within populations. Thus, myxomatosis has a low impact, with most infections being asymptomatic. This work shows that infection of young rabbits protected by maternal antibodies induces attenuated disease and activates their immune system. This may play a major role in reducing the impact of a highly lethal disease when ecological conditions enable permanent circulation of the pathogen.

  18. MDCK cell line with inducible allele B NS1 expression propagates deINS1 inflenza virus to high titres

    NARCIS (Netherlands)

    Wielink, van R.; Harmsen, M.M.; Martens, D.E.; Peeters, B.P.H.; Wijffels, R.H.; Moormann, R.J.M.

    2011-01-01

    Influenza A viruses lacking the gene encoding the non-structural NS1 protein (delNS1) have potential use as live attenuated vaccines. However, due to the lack of NS1, virus replication in cell culture is considerably reduced, prohibiting commercial vaccine production. We therefore established two st

  19. Shock propagation and attenuation in high-power excimer lasers

    Science.gov (United States)

    Holzwarth, Achim; Berger, Peter; Huegel, Helmut

    1993-05-01

    Theoretical and experimental investigations on the propagation, reflection, and attenuation of shock waves as they occur in excimer lasers have been performed. The numerical simulations have been carried out using a two-dimensional, unsteady finite difference scheme. The experimental setup is a piston driven shock tube with a rectangular cross section working in air at atmospheric pressure. The shocks were detected interferometrically as well as by means of pressure transducers. This shock tube allows us to investigate basic phenomena of shock diffraction which can be used to confirm the computational results in the range of weak shock waves. In particular, the influence of the shape of the wall contour on the reflection of shock waves has been investigated theoretically. The decay time of pressure and density perturbations differs for various wall configurations in such a way that short electrodes accelerate the attenuation as well as does a strong area increase in the vicinity of them. After each laser pulse there is a shock travelling into the laser channel. Experiments have been carried out on the reflection of this shock at a specially formed bend that is able to focus the shock into a muffling element.

  20. Vectors expressing chimeric Japanese encephalitis dengue 2 viruses.

    Science.gov (United States)

    Wei, Y; Wang, S; Wang, X

    2014-01-01

    Vectors based on self-replicating RNAs (replicons) of flaviviruses are becoming powerful tool for expression of heterologous genes in mammalian cells and development of novel antiviral and anticancer vaccines. We constructed two vectors expressing chimeric viruses consisting of attenuated SA14-14-2 strain of Japanese encephalitis virus (JEV) in which the PrM/M-E genes were replaced fully or partially with those of dengue 2 virus (DENV-2). These vectors, named pJED2 and pJED2-1770 were transfected to BHK-21 cells and produced chimeric viruses JED2V and JED2-1770V, respectively. The chimeric viruses could be passaged in C6/36 but not BHK-21 cells. The chimeric viruses produced in C6/36 cells CPE 4-5 days after infection and RT-PCR, sequencing, immunofluorescence assay (IFA) and Western blot analysis confirmed the chimeric nature of produced viruses. The immunogenicity of chimeric viruses in mice was proved by detecting DENV-2 E protein-specific serum IgG antibodies with neutralization titer of 10. Successful preparation of infectious clones of chimeric JEV-DENV-2 viruses showed that JEV-based expression vectors are fully functional.

  1. Preference by a virus vector for infected plants is reversed after virus acquisition.

    Science.gov (United States)

    Rajabaskar, Dheivasigamani; Bosque-Pérez, Nilsa A; Eigenbrode, Sanford D

    2014-06-24

    Pathogens and their vectors can interact either directly or indirectly via their shared hosts, with implications for the persistence and spread of the pathogen in host populations. For example, some plant viruses induce changes in host plants that cause the aphids that carry these viruses to settle preferentially on infected plants. Furthermore, relative preference by the vector for infected plants can change to a preference for noninfected plants after virus acquisition by the vector, as has recently been demonstrated in the wheat-Rhopalosiphum padi-Barley yellow dwarf virus pathosystem. Here we document a similar dynamic in the potato-Myzus persicae (Sulzer)-Potato leaf roll virus (PLRV) pathosystem. Specifically, in a dual choice bioassay, nonviruliferous apterous M. persicae settled preferentially on or near potato plants infected with PLRV relative to noninfected (sham-inoculated) control plants, whereas viruliferous M. persicae (carrying PLRV) preferentially settled on or near sham-inoculated potato plants relative to infected plants. The change in preference after virus acquisition also occurred in response to trapped headspace volatiles, and to synthetic mimics of headspace volatile blends from PLRV-infected and sham-inoculated potato plants. The change in preference we document should promote virus spread by increasing rates of virus acquisition and transmission by the vector.

  2. Attenuation of diacylglycerol second messengers

    Energy Technology Data Exchange (ETDEWEB)

    Bishop, W.R.; Ganong, B.R.; Bell, R.M.

    1986-05-01

    Diacylglycerol(DAG) derived from phosphatidylinositol activates protein kinase C in agonist-stimulated cells. At least two pathways may contribute to the attenuation of the DAG signal: (1) phosphorylation to phosphatidic acid(PA) by DAG kinase(DGK), and (2) deacylation by DAG and monoacylglycerol lipases. A number of DAG analogs were tested as substrates and inhibitors of partially purified pig brain DGK. Two analogs were potent inhibitors in vitro, 1-monooleoylglycerol(MOG,K/sub I/ = 91 ..mu..M) and diotanoylethyleneglycol (diC/sub 8/EG, K/sub I/ = 58 ..mu..M). These compounds were tested in human platelets. DiC/sub 8/EG inhibited (70 - 100%) (/sup 32/P/sub i/) incorporation into PA in thrombin-stimulated platelets. Under these conditions the DAG signal was somewhat long-lived but was still metabolized, presumably by the lipase pathway. MOG treatment elevated DAG levels up to 4-fold in unstimulated platelets. The DAG formed was in a pool where it did not activate protein kinase C. Thrombin-stimulation of MOG-treated platelets resulted in DAG levels 10-fold higher than control platelets. This appears to be due to the inability of these platelets to metabolize agonist-linked DAG via the lipase pathway. The development of specific inhibitors of DAG kinase and DAG lipase, in conjunction with mass quantification of DAG levels as used here, will provide further insights into the regulation of DAG second messengers.

  3. Live attenuated intranasal influenza vaccine.

    Science.gov (United States)

    Esposito, Susanna; Montinaro, Valentina; Groppali, Elena; Tenconi, Rossana; Semino, Margherita; Principi, Nicola

    2012-01-01

    Annual vaccination is the most effective means of preventing and controlling influenza epidemics, and the traditional trivalent inactivated vaccine (TIV) is by far the most widely used. Unfortunately, it has a number of limitations, the most important of which is its poor immunogenicity in younger children and the elderly, the populations at greatest risk of severe influenza. Live attenuated influenza vaccine (LAIV) has characteristics that can overcome some of these limitations. It does not have to be injected because it is administered intranasally. It is very effective in children and adolescents, among whom it prevents significantly more cases of influenza than the traditional TIV. However, its efficacy in adults has not been adequately documented, which is why it has not been licensed for use by adults by the European health authorities. LAIV is safe and well tolerated by children aged > 2 y and adults, but some concerns arisen regarding its safety in younger children and subjects with previous asthma or with recurrent wheezing. Further studies are needed to solve these problems and to evaluate the possible role of LAIV in the annual vaccination of the general population.

  4. Plant Virus Metagenomics: Advances in Virus Discovery.

    Science.gov (United States)

    Roossinck, Marilyn J; Martin, Darren P; Roumagnac, Philippe

    2015-06-01

    In recent years plant viruses have been detected from many environments, including domestic and wild plants and interfaces between these systems-aquatic sources, feces of various animals, and insects. A variety of methods have been employed to study plant virus biodiversity, including enrichment for virus-like particles or virus-specific RNA or DNA, or the extraction of total nucleic acids, followed by next-generation deep sequencing and bioinformatic analyses. All of the methods have some shortcomings, but taken together these studies reveal our surprising lack of knowledge about plant viruses and point to the need for more comprehensive studies. In addition, many new viruses have been discovered, with most virus infections in wild plants appearing asymptomatic, suggesting that virus disease may be a byproduct of domestication. For plant pathologists these studies are providing useful tools to detect viruses, and perhaps to predict future problems that could threaten cultivated plants.

  5. Delay Efficient 32-Bit Carry-Skip Adder

    Directory of Open Access Journals (Sweden)

    Yu Shen Lin

    2008-01-01

    Full Text Available The design of a 32-bit carry-skip adder to achieve minimum delay is presented in this paper. A fast carry look-ahead logic using group generate and group propagate functions is used to speed up the performance of multiple stages of ripple carry adders. The group generate and group propagate functions are generated in parallel with the carry generation for each block. The optimum block sizes are decided by considering the critical path into account. The new architecture delivers the sum and carry outputs in lesser unit delays than existing carry-skip adders. The adder is implemented in 0.25 m CMOS technology at 3.3 V. The critical delay for the proposed adder is 3.4 nanoseconds. The simulation results show that the proposed adder is 18% faster than the current fastest carry-skip adder.

  6. Zika Virus and Pregnancy

    Medline Plus

    Full Text Available ... Management Education & Events Advocacy For Patients About ACOG Zika Virus and Pregnancy Home For Patients Zika Virus and ... Patient Education Pamphlets - Spanish Share: PEV002, September 2016 Zika Virus and Pregnancy There are risks to your fetus ...

  7. Zika Virus and Pregnancy

    Science.gov (United States)

    ... Management Education & Events Advocacy For Patients About ACOG Zika Virus and Pregnancy Home For Patients Zika Virus ... Patient Education Pamphlets - Spanish Share: PEV002, September 2016 Zika Virus and Pregnancy There are risks to your ...

  8. Zika Virus and Pregnancy

    Medline Plus

    Full Text Available ... Management Education & Events Advocacy For Patients About ACOG Zika Virus and Pregnancy Home For Patients Zika Virus ... Patient Education Pamphlets - Spanish Share: PEV002, September 2016 Zika Virus and Pregnancy There are risks to your ...

  9. Computer Viruses: An Overview.

    Science.gov (United States)

    Marmion, Dan

    1990-01-01

    Discusses the early history and current proliferation of computer viruses that occur on Macintosh and DOS personal computers, mentions virus detection programs, and offers suggestions for how libraries can protect themselves and their users from damage by computer viruses. (LRW)

  10. Virus Ebola Asia

    Directory of Open Access Journals (Sweden)

    Suharyono Wuryadi

    2012-09-01

    Full Text Available Virus Marburg dan Ebola diklasifikasikan sebagai virus yang sangat menular dan dimasukkan dalam klasifikasi sebagai virus/pathogen dengan derajat biosafety 4, sehingga untuk menanganinya diperlukan laboratorium khusus tingkat 4.

  11. Graphene-based Electronically Tuneable Microstrip Attenuator

    Directory of Open Access Journals (Sweden)

    L. Pierantoni

    2014-06-01

    Full Text Available This paper presents the design of a graphene- based electronically tuneable microstrip attenuator operating at a frequency of 5 GHz. The use of graphene as a variable resistor is discussed and the modelling of its electromagnetic properties at microwave frequencies is fully addressed. The design of the graphene-based attenuator is described. The structure integrates a patch of graphene, whose characteristics can range from being a fairly good conductor to a highly lossy material, depending on the applied voltage. By applying the proper voltage through two high-impedance bias lines, the surface resistivity of graphene can be modified, thereby changing the insertion loss of the microstrip attenuator.

  12. The prevalence of transfusion transmitted virus infection in blood donors

    Institute of Scientific and Technical Information of China (English)

    Cheng Hui Huang; Ru Guang Chen; Yu Sen Zhou; Hai Tao Wang; Chun Ying Xie

    2000-01-01

    @@INTRODUCTION A newly discovered DNA virus,transfusion transmitted virus (TTV), was reported as a cause of post-transfusion hepatitis of unknown etiology in Japan[1]. In order to investigate TTV prevalence in southern China, a study was carried out among blood donors, patients with liver diseases and hemodialysis to determine the epidemiological charateristics.

  13. Oncogenic viruses and cancer

    Institute of Scientific and Technical Information of China (English)

    Guangxiang; George; Luo; Jing-hsiung; James; Ou

    2015-01-01

    <正>This special issue of the journal is dedicated to the important topic of oncogenic viruses and cancer.It contains seven review articles covering all known oncogenic viruses except for human T-lymphotropic virus type1(HTLV-1).These review articles are contributed by experts on specific viruses and their associated human cancers.Viruses account for about 20%of total human cancer cases.Although many viruses can cause various tumors in animals,only seven of them

  14. Regional carrying capacity: case studies of Bohai Rim area

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Carrying capacity research has been carried out for a long time. However, synthesized carrying capacity researches based on systematic views began only in the 1970s. There is even less work done in China. This paper tries to address both synthesized carrying capacity research and its utilization in China. State spaces method from the systematic science was borrowed to construct the conceptual model of regional carrying capacity. Based on the conceptual model and the surveys in the Bohai Rim area, we construct a representative indicators system for quantifying regional carrying capacity in the Bohai Rim. While employing system dynamic models we simulated the evolving trend of both the regional carrying states and regional carrying capacity from 1999 to 2015. The results proved the statement that Bohai Rim is overall over-capacity for a long time and will be over-capacity in the foreseeable future. Among all the restriction factors, water shortage and environmental pollution stand out to be the two primary obstacles for Bohai Rim's sustainable development.Regional differentiation analysis further indicates that coastal areas of the Bohai Rim burden more than its overall level. However, Shandong province shows some good signs in addressing the regional carrying capacity issues. The research is successful in addressing the quantification of regional carrying capacity issues, but nonetheless it needs further refinery and more information.

  15. Experimental Study of Relationships between Ultrasonic Attenuation and Dispersion for Ceramic Matrix Composite

    Science.gov (United States)

    Naumenko, A. A.; Shcherbinin, S. A.; Makariev, D. I.; Rybyanets, A. N.

    In this paper an experimental study of different ceramic matrix composites with high elastic losses and dispersion (porous piezoceramics, composites ceramics/crystals) were carried out. Complex sets of elastic, dielectric, and piezoelectric parameters of the porous piezoceramics and ceramic matrix piezocomposites were determined by the impedance spectroscopy method using Piezoelectric Resonance Analysis software. Microstructure of polished and chipped surfaces of composite samples was observed with the optical and scanning electron microcopies. Experimental frequency dependencies of attenuation coefficients and ultrasonic velocities for different ceramic matrix composites were compared with the theoretical results obtained using general Kramers-Kronig relations between the ultrasonic attenuation and dispersion.

  16. Virus-induced gene silencing and transient gene expression in soybean using Bean pod mottle virus infectious clones

    Science.gov (United States)

    Virus-induced gene silencing (VIGS) is a powerful and rapid approach for determining the functions of plant genes. The basis of VIGS is that a viral genome is engineered so that it can carry fragments of plant genes, typically in the 200-300 base pair size range. The recombinant viruses are used to ...

  17. Occurrence and distribution of pepper veinal mottle virus and cucumber mosaic virus in pepper in Ibadan, Nigeria

    Directory of Open Access Journals (Sweden)

    Arogundade Olawale

    2012-04-01

    Full Text Available Abstract Viral diseases constitute obstacles to pepper production in the world. In Nigeria, pepper plants are primarily affected by pepper veinal mottle virus (PVMV, Cucumber mosaic virus (CMV, Pepper leaf curl Virus (TLCV, Tobacco mosaic virus (TMV, Pepper mottle virus (PMV and a host of other viruses. The experiment was carried out with a diagnostic survey on the experimental field of the National Horticultural Research Institute, Ibadan, Nigeria and on pepper farms in six local government areas within Ibadan Oyo State, Nigeria, forty samples were collected from each of the farms. Diseased samples were obtained from the field and taken to the laboratory for indexing. In ELISA test some of the samples from the pepper farms showed positive reaction to single infection with PVMV (36.79%, CMV (22.14% while some others showed positive reaction to mixed infection of the two viruses (10% but some also negative reaction to PVMV and CMV antisera (31.07.

  18. STUDY OF THE MICROBIOLOGICAL ANALYSES CARRIED OUT AT THE LABORATORY OF A PUBLIC HOSPITAL (CHR AL IDRISSI OF KENITRA

    Directory of Open Access Journals (Sweden)

    A. Aziane

    2015-07-01

    Full Text Available The present work attempts to make a study on the microbiological analyses of pathogens (bacteria or viruses that are at the origin of the human disease, carried out in the laboratory of microbiological analyses of hospital regional CHR al IDRISSI of Kenitra for a period that extends from the year 2007 to 2009 in order to clarify the methodology of work and the problem of infections in developing countries. Our work is based on the monthly inventory of pathogens (E. Coli, Staphylococcus, Streptococcus, Klebsiella, Enterobacter, Candida albicans, Pseudomonas, Syphilis, hepatitis viruses and HIV in deferens samples (Urine, Pus, saddle, like and Serum in patients in relation with total analyses carried out for 3 years. Then we follow their development during this period with the analysis of the results.

  19. STUDY OF THE MICROBIOLOGICAL ANALYSES CARRIED OUT AT THE LABORATORY OF A PUBLIC HOSPITAL (CHR AL IDRISSI OF KENITRA

    Directory of Open Access Journals (Sweden)

    A. Aziane

    2014-12-01

    Full Text Available The present work attempts to make a study on the microbiological analyses of pathogens (bacteria or viruses that are at the origin of the human disease, carried out in the laboratory of microbiological analyses of hospital regional CHR al IDRISSI of Kenitra for a period that extends from the year 2007 to 2009 in order to clarify the methodology of work and the problem of infections in developing countries. Our work is based on the monthly inventory of pathogens (E. Coli, Staphylococcus, Streptococcus, Klebsiella, Enterobacter, Candida albicans, Pseudomonas, Syphilis, hepatitis viruses and HIV in deferens samples (Urine, Pus, saddle, like and Serum in patients in relation with total analyses carried out for 3 years. Then we follow their development during this period with the analysis of the results.

  20. A virus of hyperthermophilic archaea with a unique architecture among DNA viruses.

    Science.gov (United States)

    Rensen, Elena Ilka; Mochizuki, Tomohiro; Quemin, Emmanuelle; Schouten, Stefan; Krupovic, Mart; Prangishvili, David

    2016-03-01

    Viruses package their genetic material in diverse ways. Most known strategies include encapsulation of nucleic acids into spherical or filamentous virions with icosahedral or helical symmetry, respectively. Filamentous viruses with dsDNA genomes are currently associated exclusively with Archaea. Here, we describe a filamentous hyperthermophilic archaeal virus, Pyrobaculum filamentous virus 1 (PFV1), with a type of virion organization not previously observed in DNA viruses. The PFV1 virion, 400 ± 20 × 32 ± 3 nm, contains an envelope and an inner core consisting of two structural units: a rod-shaped helical nucleocapsid formed of two 14-kDa major virion proteins and a nucleocapsid-encompassing protein sheath composed of a single major virion protein of 18 kDa. The virion organization of PFV1 is superficially similar to that of negative-sense RNA viruses of the family Filoviridae, including Ebola virus and Marburg virus. The linear dsDNA of PFV1 carries 17,714 bp, including 60-bp-long terminal inverted repeats, and contains 39 predicted ORFs, most of which do not show similarities to sequences in public databases. PFV1 is a lytic virus that completely disrupts the host cell membrane at the end of the infection cycle.

  1. Early potent protection against heterologous SIVsmE660 challenge following live attenuated SIV vaccination in Mauritian cynomolgus macaques.

    Directory of Open Access Journals (Sweden)

    Neil Berry

    Full Text Available BACKGROUND: Live attenuated simian immunodeficiency virus (SIV vaccines represent the most effective means of vaccinating macaques against pathogenic SIV challenge. However, thus far, protection has been demonstrated to be more effective against homologous than heterologous strains. Immune correlates of vaccine-induced protection have also been difficult to identify, particularly those measurable in the peripheral circulation. METHODOLOGY/PRINCIPAL FINDINGS: Here we describe potent protection in 6 out of 8 Mauritian-derived cynomolgus macaques (MCM against heterologous virus challenge with the pathogenic, uncloned SIVsmE660 viral stock following vaccination with live attenuated SIVmac251/C8. MCM provided a characterised host genetic background with limited Major Histocompatibility Complex (MHC and TRIM5α allelic diversity. Early protection, observed as soon as 3 weeks post-vaccination, was comparable to that of 20 weeks vaccination. Recrudescence of vaccine virus was most pronounced in breakthrough cases where simultaneous identification of vaccine and challenge viruses by virus-specific PCR was indicative of active co-infection. Persistence of the vaccine virus in a range of lymphoid tissues was typified by a consistent level of SIV RNA positive cells in protected vaccinates. However, no association between MHC class I/II haplotype or TRIM5α polymorphism and study outcome was identified. CONCLUSION/SIGNIFICANCE: This SIV vaccine study, conducted in MHC-characterised MCM, demonstrated potent protection against the pathogenic, heterologous SIVsmE660 challenge stock after only 3 weeks vaccination. This level of protection against this viral stock by intravenous challenge has not been hitherto observed. The mechanism(s of protection by vaccination with live attenuated SIV must account for the heterologous and early protection data described in this study, including those which relate to the innate immune system.

  2. Reduced Tyk2 gene expression in β-cells due to natural mutation determines susceptibility to virus-induced diabetes

    OpenAIRE

    Izumi, Kenichi; Mine, Keiichiro; Inoue, Yoshitaka; Teshima, Miho; Ogawa, Shuichiro; Kai, Yuji; Kurafuji, Toshinobu; Hirakawa, Kanako; Miyakawa, Daiki; Ikeda, Haruka; Inada, Akari; Hara, Manami; Yamada, Hisakata; Akashi, Koichi; Niho, Yoshiyuki

    2015-01-01

    Accumulating evidence suggests that viruses play an important role in the development of diabetes. Although the diabetogenic encephalomyocarditis strain D virus induces diabetes in restricted lines of inbred mice, the susceptibility genes to virus-induced diabetes have not been identified. We report here that novel Tyrosine kinase 2 (Tyk2) gene mutations are present in virus-induced diabetes-sensitive SJL and SWR mice. Mice carrying the mutant Tyk2 gene on the virus-resistant C57BL/6 backgrou...

  3. Designing Efficacious Vesicular Stomatitis Virus-Vectored Vaccines Against Ebola Virus.

    Science.gov (United States)

    Wong, Gary; Qiu, Xiangguo

    2016-01-01

    Infection with the Ebola virus (EBOV) causes an aggressive hemorrhagic disease in humans and nonhuman primates. Traditional approaches, such as vaccination with inactivated virion preparations, have had limited efficacy, whereas immunization with live-attenuated EBOV is not feasible due to the highly lethal nature of the pathogen. This has necessitated the development of other approaches towards an effective EBOV vaccine. Over the past decade, recombinant viruses expressing the EBOV glycoprotein (GP) have constituted the most promising platforms, as evidenced by their ability to protect naïve nonhuman primates from a lethal EBOV challenge. The vesicular stomatitis virus (VSV) is one such vector and is currently progressing through the clinical pipeline. This chapter presents methodologies for the design, cloning, rescue, and preparation of live, recombinant VSV vaccines expressing GP for research purposes.

  4. The Discovery, Distribution, and Evolution of Viruses Associated with Drosophila melanogaster.

    Science.gov (United States)

    Webster, Claire L; Waldron, Fergal M; Robertson, Shaun; Crowson, Daisy; Ferrari, Giada; Quintana, Juan F; Brouqui, Jean-Michel; Bayne, Elizabeth H; Longdon, Ben; Buck, Amy H; Lazzaro, Brian P; Akorli, Jewelna; Haddrill, Penelope R; Obbard, Darren J

    2015-07-01

    Drosophila melanogaster is a valuable invertebrate model for viral infection and antiviral immunity, and is a focus for studies of insect-virus coevolution. Here we use a metagenomic approach to identify more than 20 previously undetected RNA viruses and a DNA virus associated with wild D. melanogaster. These viruses not only include distant relatives of known insect pathogens but also novel groups of insect-infecting viruses. By sequencing virus-derived small RNAs, we show that the viruses represent active infections of Drosophila. We find that the RNA viruses differ in the number and properties of their small RNAs, and we detect both siRNAs and a novel miRNA from the DNA virus. Analysis of small RNAs also allows us to identify putative viral sequences that lack detectable sequence similarity to known viruses. By surveying >2,000 individually collected wild adult Drosophila we show that more than 30% of D. melanogaster carry a detectable virus, and more than 6% carry multiple viruses. However, despite a high prevalence of the Wolbachia endosymbiont--which is known to be protective against virus infections in Drosophila--we were unable to detect any relationship between the presence of Wolbachia and the presence of any virus. Using publicly available RNA-seq datasets, we show that the community of viruses in Drosophila laboratories is very different from that seen in the wild, but that some of the newly discovered viruses are nevertheless widespread in laboratory lines and are ubiquitous in cell culture. By sequencing viruses from individual wild-collected flies we show that some viruses are shared between D. melanogaster and D. simulans. Our results provide an essential evolutionary and ecological context for host-virus interaction in Drosophila, and the newly reported viral sequences will help develop D. melanogaster further as a model for molecular and evolutionary virus research.

  5. High performance pipelined multiplier with fast carry-save adder

    Science.gov (United States)

    Wu, Angus

    1990-01-01

    A high-performance pipelined multiplier is described. Its high performance results from the fast carry-save adder basic cell which has a simple structure and is suitable for the Gate Forest semi-custom environment. The carry-save adder computes the sum and carry within two gate delay. Results show that the proposed adder can operate at 200 MHz for a 2-micron CMOS process; better performance is expected in a Gate Forest realization.

  6. Trusted Module Acquisition Through Proof-Carrying Hardware Intellectual Property

    Science.gov (United States)

    2015-05-22

    hardware intellectual property (PCHIP) framework, which aims to ensure the trustworthiness of third-party hardware IPs utilizing formal methods. We...published in non peer-reviewed journals: Final Report: Trusted Module Acquisition Through Proof-Carrying Hardware Intellectual Property Report Title By...borrowing ideas from the proof carrying code (PCC) in software domain, in this project we introduced the proof carrying hardware intellectual property

  7. Optimal design method for fast carry-skip adders

    Science.gov (United States)

    Lee, Songjun; Swartzlander, Earl E., Jr.

    2001-11-01

    A carry-skip adder is faster than a ripple carry adder and it has a simple structure. To maximize the speed it is necessary to optimize the width of the blocks that comprise the carry skip adder. This paper presents a simple algorithm to select the size of each block. Assuming that each logic gate has a unit delay, the algorithm achieves slightly faster designs for 64 and 128 bit adders than previous methods developed by Guyot, et al. and Kantabutra.

  8. Influenza A infection attenuates relaxation responses of mouse tracheal smooth muscle evoked by acrolein.

    Science.gov (United States)

    Cheah, Esther Y; Mann, Tracy S; Burcham, Philip C; Henry, Peter J

    2015-02-15

    The airway epithelium is an important source of relaxant mediators, and damage to the epithelium caused by respiratory tract viruses may contribute to airway hyperreactivity. The aim of this study was to determine whether influenza A-induced epithelial damage would modulate relaxation responses evoked by acrolein, a toxic and prevalent component of smoke. Male BALB/c mice were inoculated intranasally with influenza A/PR-8/34 (VIRUS-infected) or allantoic fluid (SHAM-infected). On day 4 post-inoculation, isometric tension recording studies were conducted on carbachol pre-contracted tracheal segments isolated from VIRUS and SHAM mice. Relaxant responses to acrolein (30 μM) were markedly smaller in VIRUS segments compared to SHAM segments (2 ± 1% relaxation vs. 28 ± 5%, n=14, pacrolein and SP were reduced in VIRUS segments (>35% reduction, n=6, pacrolein were profoundly diminished in tracheal segments isolated from influenza A-infected mice. The mechanism through which influenza A infection attenuates this response appears to involve reduced production of PGE2 in response to SP due to epithelial cell loss, and may provide insight into the airway hyperreactivity observed with influenza A infection.

  9. An unusual alphasatellite associated with monopartite begomoviruses attenuates symptoms and reduces betasatellite accumulation

    KAUST Repository

    Idris, Ali

    2010-11-17

    The Oman strain of Tomato yellow leaf curl virus (TYLCV-OM) and its associated betasatellite, an isolate of Tomato leaf curl betasatellite (ToLCB), were previously reported from Oman. Here we report the isolation of a second, previously undescribed, begomovirus [Tomato leaf curl Oman virus (ToLCOMV)] and an alphasatellite from that same plant sample. This alphasatellite is closely related (90% shared nucleotide identity) to an unusual DNA-2-type Ageratum yellow vein Singapore alphasatellite (AYVSGA), thus far identified only in Singapore. ToLCOMV was found to have a recombinant genome comprising sequences derived from two extant parents, TYLCV-OM, which is indigenous to Oman, and Papaya leaf curl virus from the Indian subcontinent. All possible combinations of ToLCOMV, TYLCV-OM, ToLCB and AYVSGA were used to agro-inoculate tomato and Nicotiana benthamiana. Infection with ToLCOMV yielded mild leaf-curl symptoms in both hosts; however, plants inoculated with TYLCV-OM developed more severe symptoms. Plants infected with ToLCB in the presence of either helper begomovirus resulted in more severe symptoms. Surprisingly, symptoms in N. benthamiana infected with the alphasatellite together with either of the helper viruses and the betasatellite were attenuated and betasatellite DNA accumulation was substantially reduced. However, in the latter plants no concomitant reduction in the accumulation of helper virus DNA was observed. This is the first example of an attenuation of begomovirus-betasatellite symptoms by this unusual class of alphasatellites. This observation suggests that some DNA-2 alphasatellites encode a pathogenicity determinant that may modulate begomovirus-betasatellite infection by reducing betasatellite DNA accumulation. © 2011 SGM.

  10. Precision Model for Microwave Rotary Vane Attenuator

    DEFF Research Database (Denmark)

    Guldbrandsen, Tom

    1979-01-01

    A model for a rotary vane attenuator is developed to describe the attenuator reflection and transmission coefficients in detail. All the parameters of the model can be measured in situ, i.e., without diassembling any part. The tranmission errors caused by internal reflections are calculated from ...... measurements of the much larger reflection parameters, hence commonly used nonprecision instruments can be used to determine the transmission errors with sufficient accuracy for the highest precision obtainable in standard laboratories....

  11. Wave attenuation charcteristics of tethered float system

    Digital Repository Service at National Institute of Oceanography (India)

    Vethamony, P.

    and transmitted wave powers, transmission coefficients are computed. The results show that transmission coefficient does not vary with changes in wave height or water depth. When depth of submergence of float increases, wave attenuation decreases, showing... that the system performs well when it is just submerged. As float velocity decreases with increase in float size, transmission coefficient increases with increase in float size. The influence of wave period on wave attenuation is remarkable compared to other...

  12. ATTENUATION AND FLANKING TRANSMISSION IN LIGHTWEIGHT STRUCTURES

    DEFF Research Database (Denmark)

    Brunskog, Jonas; Lhomond, Alice; Ohlrich, Mogens

    2007-01-01

    In this paper the attenuation and flanking transmissions of impact noise in lightweight building structures is studied using a modal approach. The structural field is mainly analysed, putting the main attention to the parts being important in the modelling. The amount of attenuation produced...... by the periodically reinforcing beams used in lightweight building structures is analysed. The consequence of these factors in modelling flanking transmission is also discussed....

  13. Rational design of genetically stable, live-attenuated poliovirus vaccines of all three serotypes: relevance to poliomyelitis eradication.

    Science.gov (United States)

    Macadam, Andrew J; Ferguson, Geraldine; Stone, David M; Meredith, Janet; Knowlson, Sarah; Auda, Ghazi; Almond, Jeffrey W; Minor, Philip D

    2006-09-01

    The global eradication of poliomyelitis caused by wild-type virus is likely to be completed within the next few years, despite immense logistic and political difficulties, and may ultimately be followed by the cessation of vaccination. However, the existing live-attenuated vaccines have the potential to revert to virulence, causing occasional disease, and viruses can be shed by immunocompromised individuals for prolonged periods of time. Moreover, several outbreaks of poliomyelitis have been shown to be caused by viruses derived from the Sabin vaccine strains. The appearance of such strains depends on the prevailing circumstances but poses a severe obstacle to strategies for stopping vaccination. Vaccine strains that are incapable of reversion at a measurable rate would provide a possible solution. Here, we describe the constructions of strains of type 3 poliovirus that are stabilized by the introduction of four mutations in the 5' noncoding region compared to the present vaccine. The strains are genetically and phenotypically stable under conditions where the present vaccine loses the attenuating mutation in the 5' noncoding region completely. Type 1 and type 2 strains in which the entire 5' noncoding regions of Sabin 1 and Sabin 2 were replaced exactly with that of one of the type 3 strains were also constructed. The genetic stability of 5' noncoding regions of these viruses matched that of the type 3 strains, but significant phenotypic reversion occurred, illustrating the potential limitations of a rational approach to the genetic stabilization of live RNA virus vaccines.

  14. Magnetically Guiding Atoms with Current-Carrying Conductors

    Institute of Scientific and Technical Information of China (English)

    刘南春; 高伟建; 印建平

    2002-01-01

    We propose a novel magnetic guide for cold neutral atoms using some current-carrying conductors. The spatial distributions of the magnetic fields from a V-shaped or U-shaped current-carrying conductor are calculated, and the relationship between the resulting magnetic field and the parameters of the current-carrying conductors is analysed in detail. The result shows that these current-carrying conductors can be used to realize a single or a controllable double magnetic guide of cold atoms in the weak-field-seeking state, and to construct various atom-optical elements, and even to realize a single-mode atomic waveguiding under certain conditions.

  15. Organization and carrying out the triathlon competitions in Ukraine

    Directory of Open Access Journals (Sweden)

    Volodymyr Vodlozerov

    2016-02-01

    Full Text Available Purpose: the aim is analyzing of system of organization and carrying out the triathlon competitions in Ukraine in accordance with rules of triathlon international federation. Material & Methods: comparative analysis of process of organization and carrying out the triathlon competitions in the world and Ukraine was carried out on basis of specialist literature studying, normative base of sports organizations (triathlon federation. Results: inconsistencies were identified in competitions carried out in cold season, particularity of triathlon that intends overcoming the combined distance without time durations between stages. Conclusions: recommendation in eliminate inconsistencies that affect to performance of triathlon competitions in Ukraine was suggested.

  16. Chikungunya, Influenza, Nipah, and Semliki Forest Chimeric Viruses with Vesicular Stomatitis Virus: Actions in the Brain.

    Science.gov (United States)

    van den Pol, Anthony N; Mao, Guochao; Chattopadhyay, Anasuya; Rose, John K; Davis, John N

    2017-03-15

    Recombinant vesicular stomatitis virus (VSV)-based chimeric viruses that include genes from other viruses show promise as vaccines and oncolytic viruses. However, the critical safety concern is the neurotropic nature conveyed by the VSV glycoprotein. VSVs that include the VSV glycoprotein (G) gene, even in most recombinant attenuated strains, can still show substantial adverse or lethal actions in the brain. Here, we test 4 chimeric viruses in the brain, including those in which glycoprotein genes from Nipah, chikungunya (CHIKV), and influenza H5N1 viruses were substituted for the VSV glycoprotein gene. We also test a virus-like vesicle (VLV) in which the VSV glycoprotein gene is expressed from a replicon encoding the nonstructural proteins of Semliki Forest virus. VSVΔG-CHIKV, VSVΔG-H5N1, and VLV were all safe in the adult mouse brain, as were VSVΔG viruses expressing either the Nipah F or G glycoprotein. In contrast, a complementing pair of VSVΔG viruses expressing Nipah G and F glycoproteins were lethal within the brain within a surprisingly short time frame of 2 days. Intranasal inoculation in postnatal day 14 mice with VSVΔG-CHIKV or VLV evoked no adverse response, whereas VSVΔG-H5N1 by this route was lethal in most mice. A key immune mechanism underlying the safety of VSVΔG-CHIKV, VSVΔG-H5N1, and VLV in the adult brain was the type I interferon response; all three viruses were lethal in the brains of adult mice lacking the interferon receptor, suggesting that the viruses can infect and replicate and spread in brain cells if not blocked by interferon-stimulated genes within the brain.IMPORTANCE Vesicular stomatitis virus (VSV) shows considerable promise both as a vaccine vector and as an oncolytic virus. The greatest limitation of VSV is that it is highly neurotropic and can be lethal within the brain. The neurotropism can be mostly attributed to the VSV G glycoprotein. Here, we test 4 chimeric viruses of VSV with glycoprotein genes from Nipah

  17. Light attenuation in estuarine mangrove lakes

    Science.gov (United States)

    Frankovich, Thomas A.; Rudnick, David T.; Fourqurean, James W.

    2017-01-01

    Submerged aquatic vegetation (SAV) cover has declined in brackish lakes in the southern Everglades characterized by low water transparencies, emphasizing the need to evaluate the suitability of the aquatic medium for SAV growth and to identify the light attenuating components that contribute most to light attenuation. Underwater attenuation of downwards irradiance of photosynthetically active radiation (PAR) was determined over a three year period at 42 sites in shallow (lakes in two sub-estuaries in the coastal Everglades, Florida USA. Turbidity, chromophoric dissolved organic matter (CDOM), and phytoplankton chlorophyll a (chl a) were measured concurrently and their respective contributions to the light attenuation rate were estimated. Light transmission to the benthos relative to literature estimates of minimum requirements for SAV growth indicated that the underwater light environment was often unsuitable for SAV. Light attenuation rates (n = 417) corrected for solar elevation angles ranged from 0.16 m-1 to 9.83 m-1 with a mean of 1.73 m-1. High concentrations of CDOM with high specific light absorption contributed the most to light attenuation followed by turbidity and chl a. CDOM alone sufficiently reduces light transmission beyond the estimated limits for SAV growth, making it difficult for ecosystem managers to increase SAV abundance by management activities. Light limitation of SAV in these areas may be a persistent feature because of their proximity to CDOM source materials from the surrounding mangrove swamp. Increasing freshwater flow into these areas may dilute CDOM concentrations and improve the salinity and light climate for SAV communities.

  18. Modulation of the Myxoma Virus Plaque Phenotype by Vaccinia Virus Protein F11

    OpenAIRE

    Irwin, Chad R.; Evans, David H.

    2012-01-01

    Vaccinia virus (VACV) produces large plaques consisting of a rapidly expanding ring of infected cells surrounding a lytic core, whereas myxoma virus (MYXV) produces small plaques that resemble a focus of transformed cells. This is odd, because bioinformatics suggests that MYXV carries homologs of nearly all of the genes regulating Orthopoxvirus attachment, entry, and exit. So why does MYXV produce foci? One notable difference is that MYXV-infected cells produce few of the actin microfilaments...

  19. Comparison of internal process control viruses for detection of food and waterborne viruses.

    Science.gov (United States)

    Blanco Fernández, María Dolores; Barrios, Melina Elizabeth; Cammarata, Robertina Viviana; Torres, Carolina; Taboga, Oscar Alberto; Mbayed, Viviana Andrea

    2017-03-29

    Enteric viruses are pathogens associated with food- and waterborne outbreaks. The recovery of viruses from food or water samples is affected by the procedures applied to detect and concentrate them. The incorporation of an internal process control virus to the analyses allows monitoring the performance of the methodology. The aim of this study was to produce a recombinant adenovirus (rAdV) and apply it together with bacteriophage PP7 as process controls. The rAdV carries a DNA construction in its genome to differentiate it from wild-type adenovirus by qPCR. The stability of both control viruses was evaluated at different pH conditions. The rAdV was stable at pH 3, 7, and 10 for 18 h. PP7 infectious particles were stable at pH 7 and showed a 2.14 log reduction at pH 10 and total decay at pH 3 after 18 h. Three virus concentration methods were evaluated: hollow-fiber tap water ultrafiltration, wastewater ultracentrifugation, and elution-PEG precipitation from lettuce. Total and infectious viruses were quantified and their recoveries were calculated. Virus recovery for rAdV and PP7 by ultrafiltration showed a wide range (2.10-84.42 and 13.54-84.62%, respectively), whereas that by ultracentrifugation was 5.05-13.71 and 6.98-13.27%, respectively. The performance of ultracentrifugation to concentrate norovirus and enteroviruses present in sewage was not significantly different to the recovery of control viruses. For detection of viruses from lettuce, genomic copies of PP7 were significantly more highly recovered than adenovirus (14.74-18.82 and 0.00-3.44%, respectively). The recovery of infectious virus particles was significantly affected during sewage ultracentrifugation and concentration from lettuce. The simultaneous use of virus controls with dissimilar characteristics and behaviors might resemble different enteric viruses.

  20. Cloned defective interfering influenza virus protects ferrets from pandemic 2009 influenza A virus and allows protective immunity to be established.

    Directory of Open Access Journals (Sweden)

    Nigel J Dimmock

    Full Text Available Influenza A viruses are a major cause of morbidity and mortality in the human population, causing epidemics in the winter, and occasional worldwide pandemics. In addition there are periodic outbreaks in domestic poultry, horses, pigs, dogs, and cats. Infections of domestic birds can be fatal for the birds and their human contacts. Control in man operates through vaccines and antivirals, but both have their limitations. In the search for an alternative treatment we have focussed on defective interfering (DI influenza A virus. Such a DI virus is superficially indistinguishable from a normal virus but has a large deletion in one of the eight RNAs that make up the viral genome. Antiviral activity resides in the deleted RNA. We have cloned one such highly active DI RNA derived from segment 1 (244 DI virus and shown earlier that intranasal administration protects mice from lethal disease caused by a number of different influenza A viruses. A more cogent model of human influenza is the ferret. Here we found that intranasal treatment with a single dose of 2 or 0.2 µg 244 RNA delivered as A/PR/8/34 virus particles protected ferrets from disease caused by pandemic virus A/California/04/09 (A/Cal; H1N1. Specifically, 244 DI virus significantly reduced fever, weight loss, respiratory symptoms, and infectious load. 244 DI RNA, the active principle, was amplified in nasal washes following infection with A/Cal, consistent with its amelioration of clinical disease. Animals that were treated with 244 DI RNA cleared infectious and DI viruses without delay. Despite the attenuation of infection and disease by DI virus, ferrets formed high levels of A/Cal-specific serum haemagglutination-inhibiting antibodies and were solidly immune to rechallenge with A/Cal. Together with earlier data from mouse studies, we conclude that 244 DI virus is a highly effective antiviral with activity potentially against all influenza A subtypes.

  1. Genome scale evolution of myxoma virus reveals host-pathogen adaptation and rapid geographic spread.

    Science.gov (United States)

    Kerr, Peter J; Rogers, Matthew B; Fitch, Adam; Depasse, Jay V; Cattadori, Isabella M; Twaddle, Alan C; Hudson, Peter J; Tscharke, David C; Read, Andrew F; Holmes, Edward C; Ghedin, Elodie

    2013-12-01

    The evolutionary interplay between myxoma virus (MYXV) and the European rabbit (Oryctolagus cuniculus) following release of the virus in Australia in 1950 as a biological control is a classic example of host-pathogen coevolution. We present a detailed genomic and phylogeographic analysis of 30 strains of MYXV, including the Australian progenitor strain Standard Laboratory Strain (SLS), 24 Australian viruses isolated from 1951 to 1999, and three isolates from the early radiation in Britain from 1954 and 1955. We show that in Australia MYXV has spread rapidly on a spatial scale, with multiple lineages cocirculating within individual localities, and that both highly virulent and attenuated viruses were still present in the field through the 1990s. In addition, the detection of closely related virus lineages at sites 1,000 km apart suggests that MYXV moves freely in geographic space, with mosquitoes, fleas, and rabbit migration all providing means of transport. Strikingly, despite multiple introductions, all modern viruses appear to be ultimately derived from the original introductions of SLS. The rapidity of MYXV evolution was also apparent at the genomic scale, with gene duplications documented in a number of viruses. Duplication of potential virulence genes may be important in increasing the expression of virulence proteins and provides the basis for the evolution of novel functions. Mutations leading to loss of open reading frames were surprisingly frequent and in some cases may explain attenuation, but no common mutations that correlated with virulence or attenuation were identified.

  2. First insights into the protective effects of a recombinant swinepox virus expressing truncated MRP of Streptococcus suis type 2 in mice.

    Science.gov (United States)

    Huang, Dongyan; Zhu, Haodan; Lin, Huixing; Xu, Jiarong; Lu, Chengping

    2012-01-01

    To explore the potential of the swinepox virus (SPV) as vector for Streptococcus suis vaccines, a vector system was developed for the construction of a recombinant SPV carrying bacterial genes. Using this system, a recombinant virus expressing truncated muramidase-released protein (MRP) of S. suis type 2 (SS2), designated rSPV-MRP, was produced and identified by PCR, western blotting and immunofluorescence assays. The rSPV-MRP was found to be only slightly attenuated in PK-15 cells, when compared with the wild-type virus. After immunization intramuscularly with rSPV-MRP, SS2 inactive vaccine (positive control), wild-type SPV (negative control) and PBS (blank control) respectively, all CD1 mice were challenged with a lethal dose or a sublethal dose of SS2 highly virulent strain ZY05719. While SS2 inactive vaccine protected all mice, immunization with rSPV-MRP resulted in 60% survival and protected mice against a lethal dose of the highly virulent SS2 strain, compared with the negative control (P MRP had a significantly reduced bacterial burden in all organs examined, compared to negative controls and blank controls (P MRP-vaccinated group were significantly higher (P MRP provided mice with protection from systemic SS2 infection. If SPV recombinants have the potential as S. suis vaccines for the use in pigs has to be evaluated in further studies.

  3. A VLP-based vaccine targeting domain III of the West Nile virus E protein protects from lethal infection in mice

    Directory of Open Access Journals (Sweden)

    Beck Markus

    2010-07-01

    Full Text Available Abstract Background Since its first appearance in the USA in 1999, West Nile virus (WNV has spread in the Western hemisphere and continues to represent an important public health concern. In the absence of effective treatment, there is a medical need for the development of a safe and efficient vaccine. Live attenuated WNV vaccines have shown promise in preclinical and clinical studies but might carry inherent risks due to the possibility of reversion to more virulent forms. Subunit vaccines based on the large envelope (E glycoprotein of WNV have therefore been explored as an alternative approach. Although these vaccines were shown to protect from disease in animal models, multiple injections and/or strong adjuvants were required to reach efficacy, underscoring the need for more immunogenic, yet safe DIII-based vaccines. Results We produced a conjugate vaccine against WNV consisting of recombinantly expressed domain III (DIII of the E glycoprotein chemically cross-linked to virus-like particles derived from the recently discovered bacteriophage AP205. In contrast to isolated DIII protein, which required three administrations to induce detectable antibody titers in mice, high titers of DIII-specific antibodies were induced after a single injection of the conjugate vaccine. These antibodies were able to neutralize the virus in vitro and provided partial protection from a challenge with a lethal dose of WNV. Three injections of the vaccine induced high titers of virus-neutralizing antibodies, and completely protected mice from WNV infection. Conclusions The immunogenicity of DIII can be strongly enhanced by conjugation to virus-like particles of the bacteriophage AP205. The superior immunogenicity of the conjugate vaccine with respect to other DIII-based subunit vaccines, its anticipated favourable safety profile and low production costs highlight its potential as an efficacious and cost-effective prophylaxis against WNV.

  4. Isolation and characterization of cidofovir resistant vaccinia viruses

    Directory of Open Access Journals (Sweden)

    Prichard Mark N

    2008-05-01

    Full Text Available Abstract Background The emergence of drug resistant viruses, together with the possibility of increased virulence, is an important concern in the development of new antiviral compounds. Cidofovir (CDV is a phosphonate nucleotide that is approved for use against cytomegalovirus retinitis and for the emergency treatment of smallpox or complications following vaccination. One mode of action for CDV has been demonstrated to be the inhibition of the viral DNA polymerase. Results We have isolated several CDV resistant (CDVR vaccinia viruses through a one step process, two of which have unique single mutations within the DNA polymerase. An additional resistant virus isolate provides evidence of a second site mutation within the genome involved in CDV resistance. The CDVR viruses were 3–7 fold more resistant to the drug than the parental viruses. The virulence of the CDVR viruses was tested in mice inoculated intranasally and all were found to be attenuated. Conclusion Resistance to CDV in vaccinia virus can be conferred individually by at least two different mutations within the DNA polymerase gene. Additional genes may be involved. This one step approach for isolating resistant viruses without serial passage and in the presence of low doses of drug minimizes unintended secondary mutations and is applicable to other potential antiviral agents.

  5. The Disillusion of American Dream in Sister Carrie

    Institute of Scientific and Technical Information of China (English)

    张晴

    2016-01-01

    Dreiser is a generally acknowledged writer as one of American's literary naturalists. In Sister Carrie, the author skillfully used the naturalistic writing style which incisively and vividly showed the society environment at that time. The paper states the process that how the American dream in Sister Carrie disillusioned gradually.

  6. 25 CFR 11.444 - Carrying concealed weapons.

    Science.gov (United States)

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Carrying concealed weapons. 11.444 Section 11.444 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAW AND ORDER COURTS OF INDIAN OFFENSES AND LAW AND ORDER CODE Criminal Offenses § 11.444 Carrying concealed weapons. A person who goes about in...

  7. 46 CFR 185.340 - Vessels carrying vehicles.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Vessels carrying vehicles. 185.340 Section 185.340... TONS) OPERATIONS Miscellaneous Operating Requirements § 185.340 Vessels carrying vehicles. (a) Automobiles or other vehicles must be stowed in such a manner as to permit both passengers and crew to get...

  8. 46 CFR 122.340 - Vessels carrying vehicles.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Vessels carrying vehicles. 122.340 Section 122.340... Miscellaneous Operating Requirements § 122.340 Vessels carrying vehicles. (a) Automobiles or other vehicles must... vehicles freely in the event of fire or other disaster. The decks, where necessary, must be...

  9. Viruses associated with epidemic hemorrhagic fevers of the Philippines and Thailand.

    Science.gov (United States)

    HAMMON, W M; RUDNICK, A; SATHER, G E

    1960-04-15

    Epidemiologic, clinical, and etiologic studies were carried out on a newly recognized, frequently fatal, pediatric disease syndrome which occurred in urban areas infested with Aedes aegypti mosquitoes. Four types of dengue virus (two of which are new), chikungunya virus, and another virus yet to be identified were isolated from the blood of patients. Dengue viruses, types 2 and 3, were isolated from the mosquitoes. Ample serologic confirmation was obtained of concurrent hemorrhagic fever and infection with one or more of these viruses. Thus, it was discovered that viruses of previously recognized types and of closely related new types apparently have etiologic roles in a new and highly dangerous epidemic disease syndrome.

  10. Analysis of Single-Mode Fiber Link Performance for Attenuation in Long-Haul Optical Networks

    Science.gov (United States)

    Kaur, Karamjit; Singh, Hardeep

    2017-03-01

    In the past decades, optical fiber has been widely used in communication system owing to low transmission losses, large information carrying capacity, small size, immunity to electrical interference and increased signal security. Focusing on increasing the network transmission capacity, control on the quality of transmission was the field that withdraws attention of research community. For this reason, fiber losses and their compensation remain the important design issue. In the present work, an effort is put in to design a system capable of doing error analysis of system for power losses taking place in the presence of attenuation effect. Attenuation is one of the important phenomena that determine the maximum possible distance between a transmitter and receiver or quantity and position of amplifiers and repeaters in optical networks. The mathematical model equations are obtained representing variation trends of bit error rate BER and Q-value with varying attenuation, which has been verified by different wavelength sources and network conditions.

  11. Anomalous attenuation of extraordinary waves in ionosphere heating experiments experimental results of 2000-2001

    CERN Document Server

    Zabotin, N A; Kovalenko, E S; Frolov, V L; Komrakov, G P; Mityakov, N A; Sergeev, E N

    2001-01-01

    Multiple scattering from artificial random irregularities HF-induced in the ionosphere F region causes significant attenuation of both ordinary and extraordinary radio waves together with the conventional anomalous absorption of ordinary waves due to their conversion into the plasma waves. To study in detail features of this effect, purposeful measurements of the attenuation of weak probing waves of the extraordinary polarization have been performed at the Sura heating facility. Characteristic scale lengths of the involved irregularities are ~0.1-1 km across the geomagnetic field lines. To determine the spectral characteristics of these irregularities from the extraordinary probing wave attenuation measurements, a simple procedure of the inverse problem solving has been implemented and some conclusions about the artificial irregularity features have been drawn. Theory and details of experiments have been stated earlier. This paper reports results of two experimental campaigns carried out in August 2000 and Ju...

  12. Improvement of quantification in SPECT studies by scatter and attenuation compensation

    Energy Technology Data Exchange (ETDEWEB)

    Younes, R.B.; Mas, J.; Bidet, R.

    1989-07-01

    The filtered backprojection images obtained from classical SPECT studies are not adequate for evaluation of volumes or parameters of clinical interest. Noise, scattering, boundary accuracy and attenuation are the main problems of SPECT quantification. It is the aim of the following study to overcome these difficulties. The first step of all correction algorithm is the contour detection of the attenuation medium. A new procedure, previously described by the authors, accurately and automatically found the boundaries of the surrounding body. The Compton scattering elimination is carried out by a modified version of Jaszczak's method. This alteration is essential to implement the iterative attenuation correction algorithm derived from Chang's method. Results obtained using computer simulation and real phantoms or clinical studies demonstrate the high improvement of contrast and count levels in the corrected slices. The process is fully automatic and the efficiency of the procedures allow fast processing of the daily SPECT examination.

  13. Inactivation of Chikungunya virus by 1,5 iodonapthyl azide

    Directory of Open Access Journals (Sweden)

    Sharma Anuj

    2012-12-01

    Full Text Available Abstract Background Chikungunya virus (CHIKV is an arthropod borne alphavirus of the family Togaviridae. CHIKV is a reemerging virus for which there is no safe prophylactic vaccine. A live attenuated strain of CHIKV, CHIK181/25, was previously demonstrated to be highly immunogenic in humans, however, it showed residual virulence causing transient arthralgia. Findings In this study, we demonstrate the complete inactivation of CHIKV181/25 by 1,5 iodonapthyl azide (INA. No cytopathic effect and virus replication was observed in cells infected with the INA-inactivated CHIKV. However, a reduction in the INA-inactivated CHIK virus-antibody binding capacity was observed by western blot analysis. Conclusion INA completely inactivated CHIKV and can further be explored for developing an inactivated-CHIKV vaccine.

  14. Development of live-attenuated arenavirus vaccines based on codon deoptimization of the viral glycoprotein.

    Science.gov (United States)

    Cheng, Benson Y H; Nogales, Aitor; de la Torre, Juan Carlos; Martínez-Sobrido, Luis

    2017-01-15

    Several arenaviruses, chiefly Lassa (LASV) in West Africa, cause hemorrhagic fever (HF) disease in humans and pose important public health problems in their endemic regions. To date, there are no FDA-approved arenavirus vaccines and current anti-arenaviral therapy is limited to the use of ribavirin that has very limited efficacy. In this work we document that a recombinant prototypic arenavirus lymphocytic choriomeningitis virus (LCMV) with a codon deoptimized (CD) surface glycoprotein (GP), rLCMV/CD, exhibited wild type (WT)-like growth properties in cultured cells despite barely detectable GP expression levels in rLCMV/CD-infected cells. Importantly, rLCMV/CD was highly attenuated in vivo but able to induce complete protection against a subsequent lethal challenge with rLCMV/WT. Our findings support the feasibility of implementing an arenavirus GP CD-based approach for the development of safe and effective live-attenuated vaccines (LAVs) to combat diseases caused by human pathogenic arenaviruses.

  15. Maximum likelihood estimation of the attenuated ultrasound pulse

    DEFF Research Database (Denmark)

    Rasmussen, Klaus Bolding

    1994-01-01

    The attenuated ultrasound pulse is divided into two parts: a stationary basic pulse and a nonstationary attenuation pulse. A standard ARMA model is used for the basic pulse, and a nonstandard ARMA model is derived for the attenuation pulse. The maximum likelihood estimator of the attenuated...

  16. Hybrid approach for attenuation correction in PET/MR scanners

    Energy Technology Data Exchange (ETDEWEB)

    Santos Ribeiro, A., E-mail: afribeiro@fc.ul.pt [Institute of Biophysics and Biomedical Engineering, Faculty of Sciences, University of Lisbon, Lisbon (Portugal); Rota Kops, E.; Herzog, H. [Institute of Neuroscience and Medicine, Forschungszentrum Juelich, Juelich (Germany); Almeida, P. [Institute of Biophysics and Biomedical Engineering, Faculty of Sciences, University of Lisbon, Lisbon (Portugal)

    2014-01-11

    Aim: Attenuation correction (AC) of PET images is still one of the major limitations of hybrid PET/MR scanners. Different methods have been proposed to obtain the AC map from morphological MR images. Although, segmentation methods normally fail to differentiate air and bone regions, while template or atlas methods usually cannot accurately represent regions anatomically different from the template image. In this study a feed forward neural network (FFNN) algorithm is presented which directly outputs the attenuation coefficients by non-linear regression of the images acquired with an ultrashort echo time (UTE) sequence guided by the template-based AC map (TAC-map). Materials and methods: MR as well as CT data were acquired in four subjects. The UTE images and the TAC-map were the inputs of the presented FFNN algorithm for training as well as classification. The resulting attenuation maps were compared with CT-based, PNN-based and TAC maps. All the AC maps were used to reconstruct the PET emission data which were then compared for the different methods. Results: For each subject dice coefficients D were calculated between each method and the respective CT-based AC maps. The resulting Ds show higher values for all FFNN-based tissues comparatively to both TAC-based and PNN-based methods, particularly for bone tissue (D=0.77, D=0.51 and D=0.71, respectively). The AC-corrected PET images with the FFNN-based map show an overall lower relative difference (RD=3.90%) than those AC-corrected with the PNN-based (RD=4.44%) or template-based (RD=4.43%) methods. Conclusion: Our results show that an enhancement of current methods can be performed by combining both information of new MR image sequence techniques and general information provided from template techniques. Nevertheless, the number of tested subjects is statistically low and current analysis for a larger dataset is being carried out.

  17. Novel controlled attenuation parameter for noninvasive assessment of steatosis using Fibroscan(®): validation in chronic hepatitis C.

    Science.gov (United States)

    Sasso, M; Tengher-Barna, I; Ziol, M; Miette, V; Fournier, C; Sandrin, L; Poupon, R; Cardoso, A-C; Marcellin, P; Douvin, C; de Ledinghen, V; Trinchet, J-C; Beaugrand, M

    2012-04-01

    A novel controlled attenuation parameter (CAP) has been developed for Fibroscan(®) to assess liver steatosis, simultaneously with liver stiffness measurement (LSM). We assessed CAP diagnostic accuracy in a large cohort of patients with chronic hepatitis C (CHC) virus. A total of 615 patients with CHC, who underwent both Fibroscan(®) and liver biopsy, were analysed. Fibrosis was graded using METAVIR score. Steatosis was categorized by visual assessment as S(0) : steatosis in Fibroscan(®) , in patients with CHC.

  18. The L, M, and S Segments of Rift Valley Fever Virus MP-12 Vaccine Independently Contribute to a Temperature-Sensitive Phenotype

    Science.gov (United States)

    Nishiyama, Shoko; Lokugamage, Nandadeva

    2016-01-01

    ABSTRACT Rift Valley fever (RVF) is endemic to Africa, and the mosquito-borne disease is characterized by “abortion storms” in ruminants and by hemorrhagic fever, encephalitis, and blindness in humans. Rift Valley fever virus (RVFV; family Bunyaviridae, genus Phlebovirus) has a tripartite negative-stranded RNA genome (L, M, and S segments). A live-attenuated vaccine for RVF, the MP-12 vaccine, is conditionally licensed for veterinary use in the United States. MP-12 is fully attenuated by the combination of the partially attenuated L, M, and S segments. Temperature sensitivity (ts) limits viral replication at a restrictive temperature and may be involved with viral attenuation. In this study, we aimed to characterize the ts mutations for MP-12. The MP-12 vaccine showed restricted replication at 38°C and replication shutoff (100-fold or greater reduction in virus titer compared to that at 37°C) at 39°C in Vero and MRC-5 cells. Using rZH501 reassortants with either the MP-12 L, M, or S segment, we found that all three segments encode a temperature-sensitive phenotype. However, the ts phenotype of the S segment was weaker than that of the M or L segment. We identified Gn-Y259H, Gc-R1182G, L-V172A, and L-M1244I as major ts mutations for MP-12. The ts mutations in the L segment decreased viral RNA synthesis, while those in the M segment delayed progeny production from infected cells. We also found that a lack of NSs and/or 78kD/NSm protein expression minimally affected the ts phenotype. Our study revealed that MP-12 is a unique vaccine carrying ts mutations in the L, M, and S segments. IMPORTANCE Rift Valley fever (RVF) is a mosquito-borne viral disease endemic to Africa, characterized by high rates of abortion in ruminants and severe diseases in humans. Vaccination is important to prevent the spread of disease, and a live-attenuated MP-12 vaccine is currently the only vaccine with a conditional license in the United States. This study determined the temperature

  19. Archaeal viruses-novel, diverse and enigmatic

    DEFF Research Database (Denmark)

    Peng, Xu; Garrett, Roger Antony; She, Qunxin

    2012-01-01

    Recent research has revealed a remarkable diversity of viruses in archaeal-rich environments where spindles, spheres, filaments and rods are common, together with other exceptional morphotypes never recorded previously. Moreover, their double-stranded DNA genomes carry very few genes exhibiting...

  20. Alphavirus mutator variants present host-specific defects and attenuation in mammalian and insect models.

    Directory of Open Access Journals (Sweden)

    Kathryn Rozen-Gagnon

    2014-01-01

    Full Text Available Arboviruses cycle through both vertebrates and invertebrates, which requires them to adapt to disparate hosts while maintaining genetic integrity during genome replication. To study the genetic mechanisms and determinants of these processes, we use chikungunya virus (CHIKV, a re-emerging human pathogen transmitted by the Aedes mosquito. We previously isolated a high fidelity (or antimutator polymerase variant, C483Y, which had decreased fitness in both mammalian and mosquito hosts, suggesting this residue may be a key molecular determinant. To further investigate effects of position 483 on RNA-dependent RNA-polymerase (RdRp fidelity, we substituted every amino acid at this position. We isolated novel mutators with decreased replication fidelity and higher mutation frequencies, allowing us to examine the fitness of error-prone arbovirus variants. Although CHIKV mutators displayed no major replication defects in mammalian cell culture, they had reduced specific infectivity and were attenuated in vivo. Unexpectedly, mutator phenotypes were suppressed in mosquito cells and the variants exhibited significant defects in RNA synthesis. Consequently, these replication defects resulted in strong selection for reversion during infection of mosquitoes. Since residue 483 is conserved among alphaviruses, we examined the analogous mutations in Sindbis virus (SINV, which also reduced polymerase fidelity and generated replication defects in mosquito cells. However, replication defects were mosquito cell-specific and were not observed in Drosophila S2 cells, allowing us to evaluate the potential attenuation of mutators in insect models where pressure for reversion was absent. Indeed, the SINV mutator variant was attenuated in fruit flies. These findings confirm that residue 483 is a determinant regulating alphavirus polymerase fidelity and demonstrate proof of principle that arboviruses can be attenuated in mammalian and insect hosts by reducing fidelity.