Science.gov

Sample records for kilham rat virus

  1. Persistent Seoul virus infection in Lewis rats.

    PubMed

    Compton, S R; Jacoby, R O; Paturzo, F X; Smith, A L

    2004-07-01

    Mechanistic studies of hantavirus persistence in rodent reservoirs have been limited by the lack of a versatile animal model. This report describes findings from experimental infection of inbred Lewis rats with Seoul virus strain 80-39. Rats inoculated with virus intraperitoneally at 6 days of age became persistently infected without clinical signs. Tissues from Seoul virus-inoculated 6-day-old rats were assessed at 6, 9, and 12 weeks post-inoculation for viral RNA by RT-PCR and in situ hybridization (ISH) and for infectious virus by inoculation of Vero E6 cells. Virus was isolated from lung and kidney of infected rats at 6 weeks and viral RNA was detected in lung, kidney, pancreas, salivary gland, brain, spleen, liver and skin at 6, 9 and 12 weeks. Rats inoculated with Seoul virus intraperitoneally at 10 or 21 days of age became infected without clinical signs but had low to undetectable levels of viral RNA in tissues at 6 weeks post-inoculation. ISH identified vascular smooth muscle and endothelial cells as common sites of persistent infection. Cultured rat smooth muscle cells and to a lesser extent cultured endothelial cells also were susceptible to Seoul virus infection. Pancreatic infection resulted in insulitis with associated hyperglycemia. These studies demonstrate that infant Lewis rats are uniformly susceptible to asymptomatic persistent Seoul virus infection. Additionally, they offer opportunities for correlative in vivo and in vitro study of Seoul virus interactions in host cell types that support persistent infection.

  2. Titration of murine leukemia viruses with rat cell line RFL.

    PubMed

    Koga, M

    1977-08-01

    Normal rat embryo cell (RFL) from syncytia after infection with murine leukemia virus. The assay for counting the number of syncytium foci produced in RFL cells is a sensitive method for a direct infectivity assay of murine leukemia virus.

  3. A rat model for hepatitis E virus

    PubMed Central

    Mishra, Niraj; Verbeken, Erik; Ramaekers, Kaat; Dallmeier, Kai

    2016-01-01

    ABSTRACT Hepatitis E virus (HEV) is one of the prime causes of acute viral hepatitis, and chronic hepatitis E is increasingly recognized as an important problem in the transplant setting. Nevertheless, the fundamental understanding of the biology of HEV replication is limited and there are few therapeutic options. The development of such therapies is partially hindered by the lack of a robust and convenient animal model. We propose the infection of athymic nude rats with the rat HEV strain LA-B350 as such a model. A cDNA clone, pLA-B350, was constructed and the infectivity of its capped RNA transcripts was confirmed in vitro and in vivo. Furthermore, a subgenomic replicon, pLA-B350/luc, was constructed and validated for in vitro antiviral studies. Interestingly, rat HEV proved to be less sensitive to the antiviral activity of α-interferon, ribavirin and mycophenolic acid than genotype 3 HEV (a strain that infects humans). As a proof-of-concept, part of the C-terminal polymerase sequence of pLA-B350/luc was swapped with its genotype 3 HEV counterpart: the resulting chimeric replicon replicated with comparable efficiency as the wild-type construct, confirming that LA-B350 strain is amenable to humanization (replacement of certain sequences or motifs by their counterparts from human HEV strains). Finally, ribavirin effectively inhibited LA-B350 replication in athymic nude rats, confirming the suitability of the rat model for antiviral studies. PMID:27483350

  4. Measles virus nucleocapsid protein protects rats from encephalitis.

    PubMed Central

    Bankamp, B; Brinckmann, U G; Reich, A; Niewiesk, S; ter Meulen, V; Liebert, U G

    1991-01-01

    Lewis rats immunized with recombinant vaccinia virus expressing the nucleocapsid (N) protein of measles virus were protected from encephalitis when subsequently challenged by intracerebral infection with neurotropic measles virus. Immunized rats revealed polyvalent antibodies to the N protein of measles virus in the absence of any neutralizing antibodies as well as an N protein-specific proliferative lymphocyte response. Depletion of CD8+ T lymphocytes did not abrogate the protective potential of the N protein-specific cell-mediated immune response in rats, while protection could be adoptively transferred with N protein-specific CD4+ T lymphocytes. These results indicate that a CD4+ cell-mediated immune response specific for the N protein of measles virus is sufficient to control measles virus infections of the central nervous system. Images PMID:1825854

  5. Susceptibility of laboratory rats against genotypes 1, 3, 4, and rat hepatitis E viruses.

    PubMed

    Li, Tian-Cheng; Yoshizaki, Sayaka; Ami, Yasushi; Suzaki, Yuriko; Yasuda, Shumpei P; Yoshimatsu, Kumiko; Arikawa, Jiro; Takeda, Naokazu; Wakita, Takaji

    2013-04-12

    To determine whether or not rats are susceptible to hepatitis E virus (HEV) infection, each of group containing three laboratory rats (Wistar) were experimentally inoculated with genotypes 1, 3, 4 and rat HEV by intravenous injection. Serum and stool samples were collected and used to detect HEV RNA and anti-HEV antibodies by RT-PCR and ELISA, respectively. The virus infection was monitored up to 3 months after inoculation. None of the serum or stool samples collected from the rats inoculated with G1, G3, or G4 HEV indicated positive sign for virus replication. Although no alteration was observed in ALT level, rat HEV RNA was detected in stools from both of the rats inoculated with rat HEV, and both rats were positive for anti-rat HEV IgG and IgM from 3 weeks after inoculation. These results demonstrated that rats are susceptible to rat HEV but not to G1, G3, and G4 HEV. We also confirm that the nude rats were useful for obtaining a large amount of rat HEV and that the rat HEV was transmitted by the fecal-oral route.

  6. Persistent Rat Virus Infection in Smooth Muscle of Euthymic and Athymic Rats

    PubMed Central

    Jacoby, Robert O.; Johnson, Elizabeth A.; Paturzo, Frank X.; Ball-Goodrich, Lisa

    2000-01-01

    Rat virus (RV) infection can cause disease or disrupt responses that rely on cell proliferation. Therefore, persistent infection has the potential to amplify RV interference with research. As a step toward determining underlying mechanisms of persistence, we compared acute and persistent RV infections in infant euthymic and athymic rats inoculated oronasally with the University of Massachusetts strain of RV. Rats were assessed by virus isolation, in situ hybridization, and serology. Selected tissues also were analyzed by Southern blotting or immunohistochemistry. Virus was widely disseminated during acute infection in rats of both phenotypes, whereas vascular smooth muscle cells (SMC) were the primary targets during persistent infection. The prevalence of virus-positive cells remained moderate to high in athymic rats through 8 weeks but decreased in euthymic rats by 2 weeks, coincident with seroconversion and perivascular infiltration of mononuclear cells. Virus-positive pneumocytes and renal tubular epithelial cells also were detected through 8 weeks, implying that kidney and lung excrete virus during persistent infection. Viral mRNA was detected in SMC of both phenotypes through 8 weeks, indicating that persistent infection includes virus replication. However, only half of the SMC containing viral mRNA at 4 weeks stained for proliferating cell nuclear antigen, a protein expressed in cycling cells. The results demonstrate that vasculotropism is a significant feature of persistent infection, that virus replication continues during persistent infection, and that host immunity reduces, but does not eliminate, infection. PMID:11090184

  7. Hepatitis E Virus Genotype 3 in Wild Rats, United States

    PubMed Central

    Volk, Kylie; Van Den Bussche, Ronald A.

    2012-01-01

    The role of rodents in the epidemiology of zoonotic hepatitis E virus (HEV) infection has been a subject of considerable debate. Seroprevalence studies suggest widespread HEV infection in commensal Rattus spp. rats, but experimental transmission has been largely unsuccessful and recovery of zoonotic genotype 3 HEV RNA from wild Rattus spp. rats has never been confirmed. We surveyed R. rattus and R. norvegicus rats from across the United States and several international populations by using a hemi-nested reverse transcription PCR approach. We isolated HEV RNA in liver tissues from 35 of 446 rats examined. All but 1 of these isolates was relegated to the zoonotic HEV genotype 3, and the remaining sequence represented the recently discovered rat genotype from the United States and Germany. HEV-positive rats were detected in urban and remote localities. Genetic analyses suggest all HEV genotype 3 isolates obtained from wild Rattus spp. rats were closely related. PMID:22840202

  8. Hepatitis E virus genotype 3 in wild rats, United States.

    PubMed

    Lack, Justin B; Volk, Kylie; Van Den Bussche, Ronald A

    2012-08-01

    The role of rodents in the epidemiology of zoonotic hepatitis E virus (HEV) infection has been a subject of considerable debate. Seroprevalence studies suggest widespread HEV infection in commensal Rattus spp. rats, but experimental transmission has been largely unsuccessful and recovery of zoonotic genotype 3 HEV RNA from wild Rattus spp. rats has never been confirmed. We surveyed R. rattus and R. norvegicus rats from across the United States and several international populations by using a hemi-nested reverse transcription PCR approach. We isolated HEV RNA in liver tissues from 35 of 446 rats examined. All but 1 of these isolates was relegated to the zoonotic HEV genotype 3, and the remaining sequence represented the recently discovered rat genotype from the United States and Germany. HEV-positive rats were detected in urban and remote localities. Genetic analyses suggest all HEV genotype 3 isolates obtained from wild Rattus spp. rats were closely related. PMID:22840202

  9. The Rat Diabetes Susceptibility Locus Iddm4 And At Least One Additional Gene Are Required For Autoimmune Diabetes Induced By Viral Infection

    PubMed Central

    Blankenhorn, Elizabeth P.; Rodemich, Lucy; Martin-Fernandez, Cristina; Leif, Jean; Greiner, Dale L.; Mordes, John P.

    2008-01-01

    BBDR rats develop autoimmune diabetes mellitus only after challenge with environmental perturbants. These include polyinosinic:polycytidylic acid (poly I:C, a ligand of toll-like receptor 3), agents that deplete regulatory T cell populations (Tregs), and a non-beta-cell-cytopathic parvovirus (Kilham rat virus, KRV). The dominant diabetes susceptibility locus Iddm4 is required for diabetes induced by treatment with poly I:C plus Treg depletion. Iddm4 is penetrant in congenic heterozygote rats on the resistant WF background, and is 79% sensitive and 80% specific as a predictor of induced diabetes. Surprisingly, an analysis of 190 (BBDR × WF)F2 rats treated with KRV after brief exposure to poly I:C revealed that the BBDR origin allele of Iddm4 is necessary but not entirely sufficient for diabetes expression. A genome scan identified a locus on chromosome 17, designated Iddm20, that is also required for susceptibility to diabetes after exposure to KRV and poly I:C (LOD score 3.7). These data suggest that the expression of autoimmune diabetes is a complex process that requires both major histocompatibility complex (MHC) genes that confer susceptibility and additional genes like Iddm4 and Iddm20 that operate only in the context of specific environmental perturbants, amplifying the immune response and the rate of disease progression. PMID:15793267

  10. Replication of clinical measles virus strains in hispid cotton rats.

    PubMed

    Wyde, P R; Moore-Poveda, D K; Daley, N J; Oshitani, H

    1999-05-01

    An alternative model to nonhuman primates to study measles virus (MV) pathogenesis, to evaluate potential MV vaccines, or to screen for potential antivirals effective against this virus is highly desirable. The laboratory-adapted Edmonston strain of MV has been reported to replicate in the lungs of hispid cotton rats following intranasal inoculation, immunosuppress infected animals, and disseminate widely from the lungs, making these animals a candidate model. However, clinical MV strains have generally not been found to grow in these animals, limiting the utility and acceptance of this model. In the present studies we demonstrate reproducible replication of several clinical MV strains in hispid cotton rats. As with the Edmonston strain, leukocytes appear to be the primary target cells of these viruses following intranasal inoculation, and extrapulmonary dissemination is common. It is also demonstrated that prior MV infection or immunization of test animals with MV vaccine prevents pulmonary tract infection. These findings should make the MV-cotton rat model more acceptable.

  11. Cowpox Virus Transmission from Pet Rats to Humans, Germany

    PubMed Central

    Campe, Hartmut; Zimmermann, Pia; Glos, Katharina; Bayer, Margot; Bergemann, Hans; Dreweck, Caroline; Graf, Petra; Weber, Bianca Kim; Meyer, Hermann; Büttner, Mathias; Busch, Ulrich

    2009-01-01

    We describe a cluster of cowpox virus (CPXV) infections in humans that occurred near Munich, Germany, around the beginning of 2009. Previously, only sporadic reports of CPXV infections in humans after direct contact with various animals had been published. This outbreak involved pet rats from the same litter. PMID:19402967

  12. Complete Genome Sequence of a Rat Hepatitis E Virus Strain Isolated in the United States

    PubMed Central

    Debing, Yannick; Emerson, Suzanne U.; Purcell, Robert H.; Dallmeier, Kai

    2014-01-01

    Hepatitis E virus is a common cause of acute hepatitis in humans. Related viruses have been isolated from multiple animal species, including rats, but their impact on human health is unclear. We present the first full-length genome sequence of a rat hepatitis E virus strain isolated in the United States (LA-B350). PMID:25377700

  13. Mouse and Cotton Rat Models of Human Respiratory Syncytial Virus.

    PubMed

    Rudd, Penny A; Chen, Weiqiang; Mahalingam, Suresh

    2016-01-01

    Human respiratory syncytial virus (hRSV) is a common respiratory virus that is usually no cause for alarm. Symptoms of hRSV usually resemble those of the common cold and can go undiagnosed. However, infants as well as the elderly are at risk for developing severe cases, which can lead to high morbidity and mortality rates especially if there are underlying health issues. Despite many years of effort, no vaccine or specific treatments exist and RSV is still the leading cause of infant hospitalizations worldwide. Here, we describe methods to infect two widely used small animal models: laboratory mice and cotton rats. PMID:27464697

  14. Neutralizing antibodies in Borna disease virus-infected rats.

    PubMed Central

    Hatalski, C G; Kliche, S; Stitz, L; Lipkin, W I

    1995-01-01

    Borna disease is a neurologic syndrome caused by infection with a nonsegmented, negative-strand RNA virus, Borna disease virus. Infected animals have antibodies to two soluble viral proteins, p40 and p23, and a membrane-associated viral glycoprotein, gp18. We examined the time course for the development of neutralization activity and the expression of antibodies to individual viral proteins in sera of infected rats. The appearance of neutralizing activity correlated with the development of immunoreactivity to gp18, but not p40 or p23. Monospecific and monoclonal antibodies to native gp18 and recombinant nonglycosylated gp18 were also found to have neutralizing activity and to immunoprecipitate viral particles or subparticles. These findings suggest that gp18 is likely to be present on the surface of the viral particles and is likely to contain epitopes important for virus neutralization. PMID:7815538

  15. Recombinant measles viruses expressing respiratory syncytial virus proteins induced virus-specific CTL responses in cotton rats.

    PubMed

    Yamaji, Yoshiaki; Nakayama, Tetsuo

    2014-07-31

    Respiratory syncytial virus (RSV) is a common cause of serious lower respiratory tract illnesses in infants. Natural infections with RSV provide limited protection against reinfection because of inefficient immunological responses that do not induce long-term memory. RSV natural infection has been shown to induce unbalanced immune response. The effective clearance of RSV is known to require the induction of a balanced Th1/Th2 immune response, which involves the induction of cytotoxic T lymphocytes (CTL). In our previous study, recombinant AIK-C measles vaccine strains MVAIK/RSV/F and MVAIK/RSV/G were developed, which expressed the RSV fusion (F) protein or glycoprotein (G). These recombinant viruses elicited antibody responses against RSV in cotton rats, and no infectious virus was recovered, but small amounts of infiltration of inflammatory cells were observed in the lungs following RSV challenge. In the present study, recombinant AIK-C measles vaccine strains MVAIK/RSV/M2-1 and MVAIK/RSV/NP were developed, expressing RSV M2-1 or Nucleoprotein (NP), respectively. These viruses exhibited temperature-sensitivity (ts), which was derived from AIK-C, and expressed respective RSV antigens. The intramuscular inoculation of cotton rats with the recombinant measles virus led to the induction of CD8(+) IFN-γ(+) cells. No infectious virus was recovered from a lung homogenate following the challenge. A Histological examination of the lungs revealed a significant reduction in inflammatory reactions without alveolar damage. These results support the recombinant measles viruses being effective vaccine candidates against RSV that induce RSV-specific CTL responses with or without the development of an antibody response.

  16. Construction and characterization of an infectious cDNA clone of rat hepatitis E virus.

    PubMed

    Li, Tian-Cheng; Yang, Tingting; Yoshizaki, Sayaka; Ami, Yasushi; Suzaki, Yuriko; Ishii, Koji; Haga, Kei; Nakamura, Tomofumi; Ochiai, Susumu; Takaji, Wakita; Johne, Reimar

    2015-06-01

    Rat hepatitis E virus (HEV) is related to human HEV and has been detected in wild rats worldwide. Here, the complete genome of rat HEV strain R63/DEU/2009 was cloned downstream of the T7 RNA polymerase promoter and capped genomic RNA generated by in vitro transcription was injected into nude rats. Rat HEV RNA could be detected in serum and faeces of rats injected intrahepatically, but not in those injected intravenously. Rat HEV RNA-positive faecal suspension was intravenously inoculated into nude rats and Wistar rats leading to rat HEV RNA detection in serum and faeces of nude rats, and to seroconversion in Wistar rats. In addition, rat HEV was isolated in PLC/PRF/5 cells from the rat HEV RNA-positive faecal suspension of nude rats and then passaged. The cell culture supernatant was infectious for nude rats. Genome analysis identified nine point mutations of the cell-culture-passaged virus in comparison with the originally cloned rat HEV genome. The results indicated that infectious rat HEV could be generated from the cDNA clone. As rats are widely used and well-characterized laboratory animals, studies on genetically engineered rat HEV may provide novel insights into organ tropism, replication and excretion kinetics as well as immunological changes induced by hepeviruses.

  17. Construction and characterization of an infectious cDNA clone of rat hepatitis E virus.

    PubMed

    Li, Tian-Cheng; Yang, Tingting; Yoshizaki, Sayaka; Ami, Yasushi; Suzaki, Yuriko; Ishii, Koji; Haga, Kei; Nakamura, Tomofumi; Ochiai, Susumu; Takaji, Wakita; Johne, Reimar

    2015-06-01

    Rat hepatitis E virus (HEV) is related to human HEV and has been detected in wild rats worldwide. Here, the complete genome of rat HEV strain R63/DEU/2009 was cloned downstream of the T7 RNA polymerase promoter and capped genomic RNA generated by in vitro transcription was injected into nude rats. Rat HEV RNA could be detected in serum and faeces of rats injected intrahepatically, but not in those injected intravenously. Rat HEV RNA-positive faecal suspension was intravenously inoculated into nude rats and Wistar rats leading to rat HEV RNA detection in serum and faeces of nude rats, and to seroconversion in Wistar rats. In addition, rat HEV was isolated in PLC/PRF/5 cells from the rat HEV RNA-positive faecal suspension of nude rats and then passaged. The cell culture supernatant was infectious for nude rats. Genome analysis identified nine point mutations of the cell-culture-passaged virus in comparison with the originally cloned rat HEV genome. The results indicated that infectious rat HEV could be generated from the cDNA clone. As rats are widely used and well-characterized laboratory animals, studies on genetically engineered rat HEV may provide novel insights into organ tropism, replication and excretion kinetics as well as immunological changes induced by hepeviruses. PMID:25634930

  18. High prevalence of rat hepatitis E virus in wild rats in China.

    PubMed

    Li, Wei; Guan, Dawei; Su, Juan; Takeda, Naokazu; Wakita, Takaji; Li, Tian-Cheng; Ke, Chang Wen

    2013-08-30

    Serum samples from a total of 713 wild rats captured in Zhanjiang city in China from December 2011 to September 2012 were investigated for the prevalence of rat hepatitis E virus (HEV) by exploring rat HEV-specific antibodies and RNA. By an ELISA based on recombinant rat HEV-like particles (HEV-LPs), 23.3% (166/713) of the rats were positive for anti-HEV IgG, and 8.3% (59/713) were positive for anti-HEV IgM. The IgG-positive rates in Rattus norvegicus, Bandicota indica, Rattus flavipectus, Rattus rattoides losea, and Rattus rattus hainanus, were 27.8% (64/230), 23.0% (40/174), 19.9% (34/171), 21.5% (26/121), and 11.8% (2/17), while the IgM-positive rates were 8.3% (19/230), 6.9% (12/174), 8.2% (14/171), 10.7% (13/121), and 5.9% (1/17), respectively. The IgG-positive rate of the rats captured in rural areas, 24.1% (84/348), was higher than that in the central area of Zhanjiang city, 15.1% (32/212). The highest IgG-positive rates, as high as 45.3% (39/86), were detected in wild rats trapped in the garbage dump. Twelve of the 59 IgM-positive serum samples were positive for HEV RNA, which was detected in all of the wild rat species except R. rattus hainanus. A phylogenetic analysis of the partial genome of rat HEV ORF1 indicated that all of the 12 HEV strains belong to rat HEV, and no other genotype HEV were detected. The rat HEV from Zhangjiang city could be classified into three separated clusters, suggesting that the infection due to rat HEV with a variety of genome entities occurs extensively among wild rats in China.

  19. Propagation and titration of Alkhumra hemorrhagic fever virus in the brains of newborn Wistar rats.

    PubMed

    Madani, Tariq A; Kao, Moujahed; Abuelzein, El-Tayeb M E; Azhar, Esam I; Al-Bar, Hussein M S; Abu-Araki, Huda; Bokhary, Rana Y; Ksiazek, Thomas G

    2014-04-01

    Alkhumra hemorrhagic fever virus (AHFV) is a novel flavivirus identified first in Saudi Arabia. In this study, successful propagation of AHFV in the brains of newborn Wistar rats is described and the median rat lethal dose (RLD50) is determined. AHFV-RNA-positive human sera diluted 1:10 were injected intracerebrally into 16, ≤24h old rats. Post-inoculation, the rats were observed daily for 30 days. Brains of moribund rats were tested for AHFV-RNA using RT-PCR and cultured in LLC-MK2 cells. The titer of the isolated virus was determined and expressed in median tissue culture infectious dose (TCID50). To determine the RLD50, AHFV brain suspension was 10-fold diluted serially and each dilution was inoculated in the cerebral hemispheres of 10 rats for a total of 90 rats. Three days post-inoculation, the rats developed tremor, irritability, convulsion, opisthotonus, and spastic paresis starting in the hind limbs and ascending to involve the whole body. All infected rats died within 3-7 days with histopathologically confirmed meningoencephalitis. AHFV-RNA was detected in the brains of all infected rats and the virus titer was 10(9.4) RLD50/ml. The virus titer in LLC-MK2 was 10(8.2) TCID50/ml. In conclusion, AHFV was propagated successfully to high titers in the brains of newborn Wistar rats.

  20. Bovine respiratory syncytial virus protects cotton rats against human respiratory syncytial virus infection.

    PubMed

    Piazza, F M; Johnson, S A; Darnell, M E; Porter, D D; Hemming, V G; Prince, G A

    1993-03-01

    Human respiratory syncytial virus (HRSV) is the most frequent cause of severe respiratory infections in infancy. No vaccine against this virus has yet been protective, and antiviral drugs have been of limited utility. Using the cotton rat model of HRSV infection, we examined bovine respiratory syncytial virus (BRSV), a cause of acute respiratory disease in young cattle, as a possible vaccine candidate to protect children against HRSV infection. Cotton rats were primed intranasally with graded doses of BRSV/375 or HRSV/Long or were left unprimed. Three weeks later, they were challenged intranasally with either BRSV/375, HRSV/Long (subgroup A), or HRSV/18537 (subgroup B). At intervals postchallenge, animals were sacrificed for virus titration and histologic evaluation. Serum neutralizing antibody titers were determined at the time of viral challenge. BRSV/375 replicated to low titers in nasal tissues and lungs. Priming with 10(5) PFU of BRSV/375 effected a 500- to 1,000-fold reduction in peak nasal HRSV titer and a greater than 1,000-fold reduction in peak pulmonary HRSV titer upon challenge with HRSV/Long or HRSV/18537. In contrast to priming with HRSV, priming with BRSV did not induce substantial levels of neutralizing antibody against HRSV and was associated with a delayed onset of clearance of HRSV upon challenge. Priming with BRSV/375 caused mild nasal and pulmonary pathology and did not cause exacerbation of disease upon challenge with HRSV/Long. Our findings suggest that BRSV may be a potential vaccine against HRSV and a useful tool for studying the mechanisms of immunity to HRSV.

  1. Measles virus replication in lungs of hispid cotton rats after intranasal inoculation.

    PubMed

    Wyde, P R; Ambrose, M W; Voss, T G; Meyer, H L; Gilbert, B E

    1992-10-01

    Hispid cotton rats were inoculated intranasally with either measles virus (MV) Edmonston, a multipassaged, tissue culture-adapted strain of MV, or with one of three clinical MV isolates that had limited passages (three to five times) in tissue culture cells. MV Edmonston was recovered from the lungs of every (n = 37) hispid cotton rat inoculated with this virus for at least 7 days after virus inoculation. Peak pulmonary titers occurred on Day +4 (3.3-4.4 log10/g lung). Scattered areas of inflammation were observed interstitially in lung sections from infected animals stained with hematoxylin and eosin, and a similar pattern of diffuse fluorescence was seen in cryostat sections stained with an indirect fluorescent antibody procedure specific for virus antigens. Fluorescent antibody and virus isolation studies on lung lavage cells both suggested that lung leukocytes were a primary target of the virus. In contrast to these findings, virus was isolated only sporadically from hispid cotton rats inoculated with any of the clinical measles virus isolates. Despite the restricted growth of MV in these animals, cotton rats may be useful for studying certain aspects of measles virus pathogenesis and for screening potential antiviral compounds in vivo.

  2. Rat hepatitis E virus derived from wild rats (Rattus rattus) propagates efficiently in human hepatoma cell lines.

    PubMed

    Jirintai, Suljid; Tanggis; Mulyanto; Suparyatmo, Joseph Benedictus; Takahashi, Masaharu; Kobayashi, Tominari; Nagashima, Shigeo; Nishizawa, Tsutomu; Okamoto, Hiroaki

    2014-06-24

    Although rat hepatitis E virus (HEV) has been identified in wild rats, no cell culture systems for this virus have been established. A recent report suggesting the presence of antibodies against rat HEV in human sera encouraged us to cultivate rat HEV in human cells. When liver homogenates obtained from wild rats (Rattus rattus) in Indonesia were inoculated onto human hepatocarcinoma cells, the rat HEV replicated efficiently in PLC/PRF/5, HuH-7 and HepG2 cells, irrespective of its genetic group (G1-G3). The rat HEV particles released from cultured cells harbored lipid-associated membranes on their surface that were depleted by treatment with detergent and protease, with the buoyant density in sucrose shifting from 1.15-1.16 g/ml to 1.27-1.28 g/ml. A Northern blotting analysis revealed genomic RNA of 7.0 kb and subgenomic RNA of 2.0 kb in the infected cells. The subgenomic RNA of G1-G3 each possessed the extreme 5'-end sequence of GUAGC (nt 4933-4937), downstream of the highly conserved sequence of GAAUAACA (nt 4916-4923). The establishment of culture systems for rat HEV would allow for extended studies of the mechanisms of viral replication and functional roles of HEV proteins. Further investigation is required to clarify the zoonotic potential of rat HEV.

  3. Molecular and serological evidence for Seoul virus in rats (Rattus norvegicus) in Zhangmu, Tibet, China.

    PubMed

    Hu, Tingsong; Fan, Quanshui; Hu, Xiaobing; Deng, Bo; Chen, Gang; Gu, Liangqi; Li, Ming; Zheng, Ying; Yuan, Guihong; Qiu, Wei; Jiang, Xiaomei; Zhang, Fuqiang

    2015-05-01

    We report the detection of a virus, tentatively identified as Seoul virus (SEOV), from a rat (Rattus norvegicus) collected in the city of Zhangmu, Tibet. SEOV RNA was detected in lung tissue by reverse transcription (RT)-PCR, followed by sequencing. Serum samples collected from Zhangmu were positive for SEOV-specific antibodies (indirect fluorescent antibody test that used SEO antigen). Sequencing and phylogenetic analysis of partial L and S sequences together with serology results suggest that the Zhangmu01 hantavirus is an isolate of SEOV, that hantaviruses circulate in Tibet, and that rats may act as natural reservoirs for the virus.

  4. Distinct transformation phenotypes induced by polyoma virus and simian virus 40 in rat fibroblasts and their control by an early viral gene function.

    PubMed Central

    Perbal, B; Rassoulzadegan, M

    1980-01-01

    Several transformed cell lines established from Fisher rat cells (FR 3T3) infected with wild-type polyoma virus or simian virus 40 or early temperature-sensitive mutants (polyoma tsa and simian virus 40 tsA30) were studied for their transformation phenotypes. The distinct patterns which were obtained for polyoma and simian virus 40 transformants led to the conclusion that these two viruses express different transforming abilities in rat cells. The results obtained with temperature-sensitive mutant-derived transformants indicate that all of the transformation characteristics studied so far may be under the control of a viral function in polyoma tsa-transformed cells. Images PMID:6251242

  5. Replication of parainfluenza (Sendai) virus in isolated rat pulmonary type II alveolar epithelial cells.

    PubMed Central

    Castleman, W. L.; Northrop, P. J.; McAllister, P. K.

    1989-01-01

    The major objectives of this study were to determine whether alveolar type II epithelial cells isolated from rat lung and maintained in tissue culture would support productive replication of parainfluenza type 1 (Sendai) virus and to determine whether isolated type II cells from neonatal (5-day-old) rats that are more susceptible to viral-induced alveolar dysplasia supported viral replication to a greater extent than those from weanling (25-day-old) rats. Isolated and cultured type II cells from neonatal and weanling rats that were inoculated with Sendai virus supported productive replication as indicated by ultrastructural identification of budding virions and viral nucleocapsids in type II cells and by demonstration of rising titers of infectious virus from inoculated type II cell cultures. Alveolar macrophages from neonatal and weanling rats also supported viral replication, although infectious viral titers in macrophage cultures were lower than those from type II cell cultures. Only minor differences were detected between viral titers from neonatal and weanling type II epithelial cell cultures. Higher densities of viral nucleocapsids were observed in neonatal type II cells than in those from weanling rats. The results indicate that isolated type II alveolar epithelial cells support productive replication of parainfluenza virus and that type II cells are probably more efficient in supporting productive viral replication than are alveolar macrophages. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 PMID:2541612

  6. Infection of cultured rat myotubes and neurons from the spinal cord by rabies virus.

    PubMed

    Tsiang, H; de la Porte, S; Ambroise, D J; Derer, M; Koenig, J

    1986-01-01

    Rabies virus multiplication was investigated in cultured primary rat myotubes and neurons. The susceptibility of these two cell types to fixed rabies challenge virus strain (CVS) was monitored by fluorescence and virus titration. Differentiated rat myotubes were susceptible to rabies virus infection, and showed an increasing accumulation of viral material from day one to day four. However, these cells did not release infective viral particles, nor did they accumulate infectious virions in the cytoplasm. In contrast, infected neurons released large amounts of infectious particles. Electron microscopy observation of infected myotubes showed minor alterations and the presence of typical viral inclusions in the cytoplasm without mature virions assembling viral membranes. Competition binding experiments show that alpha-bungarotoxin inhibits rabies virus infection from 10(-5) to 10(-7) M, whereas lower toxin concentrations failed to have any effect. These data do not confirm the hypothesis of a fixed rabies virus amplification step at the site of the viral entry. On the other hand, the high susceptibility of peripheral neurons to rabies virus infection is an argument for the direct uptake of virions by these cells. The restrictive viral multiplication in the myotubes is an alternative explanation for the local persistence of rabies virus at the site of inoculation.

  7. Characterization of murine hepatitis virus (JHM) RNA from rats with experimental encephalomyelitis.

    PubMed

    Jackson, D P; Percy, D H; Morris, V L

    1984-09-01

    When Wistar Furth rats are inoculated intracerebrally with the murine hepatitis virus JHM they often develop a demyelinating disease with resulting hind leg paralysis. Using an RNA transfer procedure and hybridization kinetic analysis, the virus-specific RNA in these rats was characterized. The pattern of JHM-specific RNA varied with individual infections of Wistar Furth rats. However, two species of JHM-specific RNA, the nucleocapsid and a 2.1-2.4 X 10(6)-Da RNA species were generally present. A general decrease in JHM-specific RNA in brains and spinal cord samples taken later than 20 days postinoculation was observed; however, JHM-specific RNA persisted in the spinal cord longer than in the brain of these rats.

  8. The simultaneous occurrence of human norovirus and hepatitis E virus in a Norway rat (Rattus norvegicus).

    PubMed

    Wolf, Sandro; Reetz, Jochen; Johne, Reimar; Heiberg, Ann-Charlotte; Petri, Samuel; Kanig, Hanna; Ulrich, Rainer G

    2013-07-01

    Wild rats can be reservoirs and vectors for several human pathogens. An initial RT-PCR screening of the intestinal contents of Norway rats trapped in the sewer system of Copenhagen, Denmark, for caliciviruses revealed the presence of a human norovirus in one of 11 rodents. Subsequent phylogenetic analysis of the ~4.0-kb 3'-terminus of the norovirus genome resulted in the identification of a recombinant GI.b/GI.6 strain. The simultaneous detection of hepatitis E virus-like particles in the feces of this rat by transmission electron microscopy was confirmed by RT-PCR and sequence determination, resulting in the identification of a novel rat hepatitis E virus. PMID:23443935

  9. KINETIC PROFILE OF INFLUENZA VIRUS INFECTION IN THREE RAT STRAINS

    EPA Science Inventory

    Abstract

    Influenza infection is a respiratory disease of viral origin that can cause major epidemics in man. The influenza virus infects and damages epithelial cells of the respiratory tract and causes pneumonia. Lung lesions of mice infected with influenza virus resembl...

  10. Cotton Rat (Sigmodon hispidus) Signaling Lymphocyte Activation Molecule (CD150) Is an Entry Receptor for Measles Virus

    PubMed Central

    Carsillo, Thomas; Huey, Devra; Levinsky, Amy; Obojes, Karola; Schneider-Schaulies, Jürgen; Niewiesk, Stefan

    2014-01-01

    Cotton rats (Sigmodon hispidus) replicate measles virus (MV) after intranasal infection in the respiratory tract and lymphoid tissue. We have cloned the cotton rat signaling lymphocytic activation molecule (CD150, SLAM) in order to investigate its role as a potential receptor for MV. Cotton rat CD150 displays 58% and 78% amino acid homology with human and mouse CD150, respectively. By staining with a newly generated cotton rat CD150 specific monoclonal antibody expression of CD150 was confirmed in cotton rat lymphoid cells and in tissues with a pattern of expression similar to mouse and humans. Previously, binding of MV hemagglutinin has been shown to be dependent on amino acids 60, 61 and 63 in the V region of CD150. The human molecule contains isoleucine, histidine and valine at these positions and binds to MV-H whereas the mouse molecule contains valine, arginine and leucine and does not function as a receptor for MV. In the cotton rat molecule, amino acids 61 and 63 are identical with the mouse molecule and amino acid 60 with the human molecule. After transfection with cotton rat CD150 HEK 293 T cells became susceptible to infection with single cycle VSV pseudotype virus expressing wild type MV glycoproteins and with a MV wildtype virus. After infection, cells expressing cotton rat CD150 replicated virus to lower levels than cells expressing the human molecule and formed smaller plaques. These data might explain why the cotton rat is a semipermissive model for measles virus infection. PMID:25295727

  11. Frequent detection and characterization of hepatitis E virus variants in wild rats (Rattus rattus) in Indonesia.

    PubMed

    Mulyanto; Depamede, Sulaiman Ngongu; Sriasih, Made; Takahashi, Masaharu; Nagashima, Shigeo; Jirintai, Suljid; Nishizawa, Tsutomu; Okamoto, Hiroaki

    2013-01-01

    One hundred sixteen rats (Rattus rattus) captured in Indonesia from 2011 to 2012 were investigated for the prevalence of hepatitis E virus (HEV)-specific antibodies and HEV RNA. Using an ELISA based on HEV genotype 4 with an ad hoc cutoff value of 0.500, 18.1 % of the rats tested positive for anti-HEV IgG. By nested RT-PCR, 14.7 % of the rats had rat HEV RNA, and none were positive for HEV genotype 1-4. A high HEV prevalence among rats was associated with lower sanitary conditions in areas with a high population density. Sixteen of the 17 HEV isolates obtained from infected rats showed >93.0 % nucleotide sequence identity within the 840-nucleotide ORF1-ORF2 sequence and were most closely related to a Vietnamese strain (85.9-87.9 % identity), while the remaining isolate differed from known rat HEV strains by 18.8-23.3 % and may belong to a novel lineage of rat HEV. These results suggest a wide distribution of rat HEV with divergent genomes. PMID:22983110

  12. Use of cotton rats to evaluate the efficacy of antivirals in treatment of measles virus infections.

    PubMed

    Wyde, P R; Moore-Poveda, D K; De Clercq, E; Neyts, J; Matsuda, A; Minakawa, N; Guzman, E; Gilbert, B E

    2000-05-01

    No practical animal models for the testing of chemotherapeutic or biologic agents identified in cell culture assays as being active against measles virus (MV) are currently available. Cotton rats may serve this purpose. To evaluate this possibility, 5-ethynyl-1-beta-D-ribofuranosylimidazole-4-carboxamide (EICAR) and poly(acrylamidomethyl propanesulfonate) (PAMPS), two compounds that have been reported to inhibit MV in vitro, and ribavirin, an established antiviral drug with MV-inhibitory activity, were evaluated for their antiviral activities against MV and respiratory syncytial virus (RSV) in tissue culture and in hispid cotton rats. A single administration of PAMPS markedly inhibited pulmonary RSV or MV replication (>3 log(10) reduction in pulmonary titer compared to that for controls), but only if this compound was administered intranasally at about the time of virus inoculation. Both EICAR and ribavirin exhibited therapeutic activity against RSV and MV in cotton rats when they were administered parenterally. However, both of these compounds were less effective against MV. On the basis of the pulmonary virus titers on day 4 after virus inoculation, the minimal efficacious dose of EICAR against MV (120 mg/kg of body weight/day when delivered intraperitoneally twice daily) appeared to be three times lower against this virus than that of ribavirin delivered at a similar dose (i.e., 360 mg/kg/day). These findings correlated with those obtained in vitro. The data obtained suggest that cotton rats may indeed be useful for the initial evaluation of the activities of antiviral agents against MV.

  13. Differential expression of immunoregulatory genes in male and female Norway rats following infection with Seoul virus.

    PubMed

    Klein, Sabra L; Cernetich, Amy; Hilmer, Sara; Hoffman, Eric P; Scott, Alan L; Glass, Gregory E

    2004-09-01

    Males of many species are more susceptible than females to infections caused by parasites, bacteria, fungi, and viruses. Following inoculation with Seoul virus, male rats have more virus present in target organs and shed virus longer than females. The goal of this study was to test the hypothesis that variation in the expression of genes associated with immune function mediates sex differences in hantavirus infection. Using DNA microarrays, we examined changes in gene expression in lung tissue during the early (when animals are viremic and shedding virus; Day 15 post-inoculation (p.i.)) and late (animals have low levels of infectious virus, but high antibody titers; Day 40 p.i.) phases of infection in adult male and female rats. After normalizing the gene expression levels from infected animals to the gene expression levels from same-sex uninfected controls, our data revealed that 1,813 genes were differentially expressed between the sexes during infection. The expression of key transcriptional factors (e.g., eIF-2 alpha, NF-kappa B, IRF-1, NF-IL-6, and STAT6) and genes that encode for proinflammatory (e.g., TNF alpha R, IL-1R, and IL-1RAcP), antiviral (e.g., IFN gamma R and Mx proteins), T cell (e.g., CD3 and TCR), and Ig superfamily (e.g., IgM, IgG, and MHC class I and II) proteins was higher in females than males. Conversely, males had higher expression of heat shock protein genes (e.g., hsp70) suggesting that cellular stress is elevated in males. These data provide candidate genes and cellular pathways that may underlie sex differences in responses to Seoul virus and possibly other hemorrhagic fever viruses.

  14. Sex differences in the recognition of and innate antiviral responses to Seoul virus in Norway rats.

    PubMed

    Hannah, Michele F; Bajic, Vladimir B; Klein, Sabra L

    2008-05-01

    Among rodents that carry hantaviruses, more males are infected than females. Male rats also have elevated copies of Seoul virus RNA and reduced transcription of immune-related genes in the lungs than females. To further characterize sex differences in antiviral defenses and whether these differences are mediated by gonadal hormones, we examined viral RNA in the lungs, virus shedding in saliva, and antiviral defenses among male and female rats that were intact, gonadectomized neonatally, or gonadectomized in adulthood. Following inoculation with Seoul virus, high amounts viral RNA persisted longer in lungs from intact males than intact females. Removal of the gonads in males reduced the amount of viral RNA to levels comparable with intact females at 40 days post-inoculation (p.i.). Intact males shed more virus in saliva than intact females 15 days p.i.; removal of the gonads during either the neonatal period or in adulthood increased virus shedding in females and decreased virus shedding in males. Induction of pattern recognition receptors (PRRs; Tlr7 and Rig-I), expression of antiviral genes (Myd88, Visa, Jun, Irf7, Ifnbeta, Ifnar1, Jak2, Stat3, and Mx2), and production of Mx protein was elevated in the lungs of intact females compared with intact males. Gonadectomy had more robust effects on the induction of PRRs than on downstream IFNbeta or Mx2 expression. Putative androgen and estrogen response elements are present in the promoters of several of these antiviral genes, suggesting the propensity for sex steroids to directly affect dimorphic antiviral responses against Seoul virus infection.

  15. Metagenomic identification of novel enteric viruses in urban wild rats and genome characterization of a group A rotavirus.

    PubMed

    Sachsenröder, Jana; Braun, Anne; Machnowska, Patrycja; Ng, Terry Fei Fan; Deng, Xutao; Guenther, Sebastian; Bernstein, Samuel; Ulrich, Rainer G; Delwart, Eric; Johne, Reimar

    2014-12-01

    Rats are known as reservoirs and vectors for several zoonotic pathogens. However, information on the viruses shed by urban wild rats that could pose a zoonotic risk to human health is scare. Here, intestinal contents from 20 wild Norway rats (Rattus norvegicus) collected in the city of Berlin, Germany, were subjected to metagenomic analysis of viral nucleic acids. The determined faecal viromes of rats consisted of a variety of known and unknown viruses, and were highly variable among the individuals. Members of the families Parvoviridae and Picobirnaviridae represented the most abundant species. Novel picornaviruses, bocaviruses, sapoviruses and stool-associated circular ssDNA viruses were identified, which showed only low sequence identity to known representatives of the corresponding taxa. In addition, noroviruses and rotaviruses were detected as potential zoonotic gastroenteritis viruses. However, partial-genome sequence analyses indicated that the norovirus was closely related to the recently identified rat norovirus and the rotavirus B was closely related to the rat rotavirus strain IDIR; both viruses clustered separately from respective human virus strains in phylogenetic trees. In contrast, the rotavirus A sequences showed high identity to human and animal strains. Analysis of the nearly complete genome of this virus revealed the known genotypes G3, P[3] and N2 for three of the genome segments, whereas the remaining eight genome segments represented the novel genotypes I20-R11-C11-M10-A22-T14-E18-H13. Our results indicated a high heterogeneity of enteric viruses present in urban wild rats; their ability to be transmitted to humans remains to be assessed in the future. PMID:25121550

  16. EFFECTS OF ALLERGIC AIRWAYS DISEASE ON INFLUENZA VIRUS INFECTION IN BROWN NORWAY RATS

    EPA Science Inventory

    EFFECTS OF ALLERGIC AIRWAYS DISEASE ON INFLUENZA VIRUS INFECTION IN BROWN NORWAY RATS (P. Singhl, D.W. Winsett2, M.J. Daniels2,
    C.A.J. Dick', K.B. Adlerl and M.I. Gilmour2, INCSU, Raleigh, N.C., 2NHEERL/ORD/ USEPA, RTP, N.C. and 3UNC, Chapel Hill, N.C.)The interaction between ...

  17. Transabdominal lymphography after intraperitoneal injection of Rous virus in newborn rats.

    PubMed

    Forsby, N; Jonsson, K; Olin, T

    1978-01-01

    Newborn rats were inoculated in the peritoneal cavity with Rous sarcoma virus (Schmidt-Ruppin strain). They were studied lymphographically and histologically after various intervals of time. As a result of lesions of the lymph vessels and nodes, the lymphatic drainage of the peritoneal cavity was increasingly impaired. Pleural effusion developed as a result of leakage through the walls of the lymphatics. The passage through the lymph nodes was blocked and large lymph cysts arose in the mediastinum and retroperitoneally.

  18. Coronavirus infection in the laboratory rat: immunization trials using attenuated virus replicated in L-2 cells.

    PubMed

    Percy, D H; Scott, R A

    1991-01-01

    Sixty-nine specific pathogen-free male Wistar rats approximately eight weeks of age were used to evaluate the efficacy of an attentuated strain of sialodacryoadenitis (SDA) virus in providing protection against infection on subsequent challenge with virulent SDA virus. Fifty-four animals were inoculated intranasally with approximately 10(3.5) median cell culture infectious doses of the 25th passage of SDA virus in L-2 cells. Randomly-selected vaccinated animals were killed in order to evaluate the safety and efficacy of attenuated virus by histopathological examination of the salivary glands, lacrimal glands, and lower respiratory tract, and titration of sera for antibody to SDA virus. At three months and six months postvaccination (pv), animals were selected at random and challenged with virulent SDA virus. Seronegative, age-matched animals were also challenged, and served as controls. In animals examined at six to ten days pv, lesions were absent in submandibular and parotid salivary glands and lacrimal glands, but transient lesions were present in major airways of the lower respiratory tract. In a comparison of the incidence and extent of lesions, and antibody titers in challenged vaccinates and seronegative controls, lesions were minimal or absent in vaccinates compared to challenged naive rats, particularly in animals inoculated at three months pv. In addition, antibody titers in challenged vaccinates were much higher than were postinoculation titers in inoculated controls. In a comparison of lesions in salivary and lacrimal glands in vaccinated and control animals challenged at six months pv, there was a significant reduction in the number of animals without lesions in the vaccinated group (p = less than 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)

  19. Five recombinant simian immunodeficiency virus pseudotypes lead to exclusive transduction of retinal pigmented epithelium in rat.

    PubMed

    Duisit, Ghislaine; Conrath, Hervé; Saleun, Sylvie; Folliot, Sebastien; Provost, Nathalie; Cosset, François-Loïc; Sandrin, Virginie; Moullier, Philippe; Rolling, Fabienne

    2002-10-01

    The purpose of our study was to evaluate lentiviral vector-mediated rat retinal transduction using simian immunodeficiency virus (SIV) pseudotyped with envelope proteins from vesicular stomatitis virus G glycoprotein (VSV-G), Mokola virus G protein (MK-G), amphotropic murine leukemia virus envelope (4070A-Env), influenza A virus hemagglutinin (HA), lymphocytic choriomeningitis virus G protein (LCMV-G), and RD114 retrovirus envelope (RD114-Env). The six pseudotyped lentivirus vectors carried CMV-driven green fluorescent protein (GFP) or beta-galactosidase (beta-gal) reporter genes. Intravitreal and subretinal injections of each pseudotyped recombinant SIV were performed in cohorts of Wistar rats. Our results showed that no transgene expression was detected after intravitreal injection of each pseudotyped SIV vector. Also, no transduction could be detected following subretinal injection of RD114 pseudotyped SIV vectors. However, selective transduction of retinal pigment epithelium (RPE) cells was repeatedly obtained after subretinal delivery of VSV-G, MK-G, 4070A-Env, HA, and LCMV-G pseudotyped SIV. GFP expression was maximum as soon as 4 days postadministration for VSV-G, MK-G, 4070A-Env, and HA pseudotypes, with no evidence of pseudotransduction for VSV-G. Maximum transgene expression was observed 3 weeks postinjection for LCMV-6. Importantly, HA and VSV-G pseudotyped SIV lead to such a high level of transgene expression that GFP-related toxicity occurred. Therefore, when a high level of GFP synthesis is achieved, replacement of enhanced GFP (egfp, Aequorea victoria) by a low-toxicity GFP (Renilla reniformis) cDNA is necessary to allow long-term expression.

  20. An in vivo and in vitro study of rabies virus infection of the rat superior cervical ganglia.

    PubMed

    Tsiang, H; Derer, M; Taxi, J

    1983-01-01

    In the attempt to develop a homogeneous neuronal model to study rabies pathogenesis in vivo and in vitro, the superior cervical ganglia (SCG) were chosen because of their unique features. In vivo infection of the SCG was attempted by inoculation of fixed rabies virus into the anterior eye chamber. However, viral by this route as well as intracerebrally failed to infect this neuronal organ in adult rats whereas the infection was poorly efficient in 24 hours newborn rats. Dissociated cell cultures from the rat embryo SCG were infected in vitro and examined for the presence of rabies specific antigen and release of virus particles in the supernatant. Despite the presence of rabies nucleoprotein in the cytoplasm and the presence of typical Negri bodies, neurons from the rat SCG produced few particles as observed by electron microscopy and no increase in virus yields could be detected by titration of viral infectivity during the infectious cycle. Our observations indicate that although rabies virus is neurotropic as shown in previous studies, all neuronal tissues are not equally susceptible to this viral infection. The resistance of the SCG to rabies virus infection in vivo does not seems to be a lack of accessibility of this organ to infection since other authors had shown that it could be infected by herpes virus. Both in vitro and in vivo experiments show that although neurons from the SCG are susceptible to rabies virus infection, infected cells do not produce rabies infectious virions efficiently.

  1. Bioluminescent imaging of vaccinia virus infection in immunocompetent and immunodeficient rats as a model for human smallpox

    PubMed Central

    Liu, Qiang; Fan, Changfa; Zhou, Shuya; Guo, Yanan; Zuo, Qin; Ma, Jian; Liu, Susu; Wu, Xi; Peng, Zexu; Fan, Tao; Guo, Chaoshe; Shen, Yuelei; Huang, Weijin; Li, Baowen; He, Zhengming; Wang, Youchun

    2015-01-01

    Due to the increasing concern of using smallpox virus as biological weapons for terrorist attack, there is renewed interest in studying the pathogenesis of human smallpox and development of new therapies. Animal models are highly demanded for efficacy and safety examination of new vaccines and therapeutic drugs. Here, we demonstrated that both wild type and immunodeficient rats infected with an engineered vaccinia virus carrying Firefly luciferase reporter gene (rTV-Fluc) could recapitulate infectious and clinical features of human smallpox. Vaccinia viral infection in wild type Sprague-Dawley (SD) rats displayed a diffusible pattern in various organs, including liver, head and limbs. The intensity of bioluminescence generated from rTV-Fluc correlated well with viral loads in tissues. Moreover, neutralizing antibodies had a protective effect against virus reinfection. The recombination activating gene 2 (Rag2) knockout rats generated by transcription activator-like effector nucleases (TALENs) technology were further used to examine the infectivity of the rTV-Fluc in immunodeficient populations. Here we demonstrated that Rag2-/- rats were more susceptible to rTV-Fluc than SD rats with a slower virus clearance rate. Therefore, the rTV-Fluc/SD rats and rTV-Fluc/Rag2-/- rats are suitable visualization models, which recapitulate wild type or immunodeficient populations respectively, for testing human smallpox vaccine and antiviral drugs. PMID:26235050

  2. Bioluminescent imaging of vaccinia virus infection in immunocompetent and immunodeficient rats as a model for human smallpox.

    PubMed

    Liu, Qiang; Fan, Changfa; Zhou, Shuya; Guo, Yanan; Zuo, Qin; Ma, Jian; Liu, Susu; Wu, Xi; Peng, Zexu; Fan, Tao; Guo, Chaoshe; Shen, Yuelei; Huang, Weijin; Li, Baowen; He, Zhengming; Wang, Youchun

    2015-01-01

    Due to the increasing concern of using smallpox virus as biological weapons for terrorist attack, there is renewed interest in studying the pathogenesis of human smallpox and development of new therapies. Animal models are highly demanded for efficacy and safety examination of new vaccines and therapeutic drugs. Here, we demonstrated that both wild type and immunodeficient rats infected with an engineered vaccinia virus carrying Firefly luciferase reporter gene (rTV-Fluc) could recapitulate infectious and clinical features of human smallpox. Vaccinia viral infection in wild type Sprague-Dawley (SD) rats displayed a diffusible pattern in various organs, including liver, head and limbs. The intensity of bioluminescence generated from rTV-Fluc correlated well with viral loads in tissues. Moreover, neutralizing antibodies had a protective effect against virus reinfection. The recombination activating gene 2 (Rag2) knockout rats generated by transcription activator-like effector nucleases (TALENs) technology were further used to examine the infectivity of the rTV-Fluc in immunodeficient populations. Here we demonstrated that Rag2-/- rats were more susceptible to rTV-Fluc than SD rats with a slower virus clearance rate. Therefore, the rTV-Fluc/SD rats and rTV-Fluc/Rag2-/- rats are suitable visualization models, which recapitulate wild type or immunodeficient populations respectively, for testing human smallpox vaccine and antiviral drugs. PMID:26235050

  3. Bioluminescent imaging of vaccinia virus infection in immunocompetent and immunodeficient rats as a model for human smallpox.

    PubMed

    Liu, Qiang; Fan, Changfa; Zhou, Shuya; Guo, Yanan; Zuo, Qin; Ma, Jian; Liu, Susu; Wu, Xi; Peng, Zexu; Fan, Tao; Guo, Chaoshe; Shen, Yuelei; Huang, Weijin; Li, Baowen; He, Zhengming; Wang, Youchun

    2015-08-03

    Due to the increasing concern of using smallpox virus as biological weapons for terrorist attack, there is renewed interest in studying the pathogenesis of human smallpox and development of new therapies. Animal models are highly demanded for efficacy and safety examination of new vaccines and therapeutic drugs. Here, we demonstrated that both wild type and immunodeficient rats infected with an engineered vaccinia virus carrying Firefly luciferase reporter gene (rTV-Fluc) could recapitulate infectious and clinical features of human smallpox. Vaccinia viral infection in wild type Sprague-Dawley (SD) rats displayed a diffusible pattern in various organs, including liver, head and limbs. The intensity of bioluminescence generated from rTV-Fluc correlated well with viral loads in tissues. Moreover, neutralizing antibodies had a protective effect against virus reinfection. The recombination activating gene 2 (Rag2) knockout rats generated by transcription activator-like effector nucleases (TALENs) technology were further used to examine the infectivity of the rTV-Fluc in immunodeficient populations. Here we demonstrated that Rag2-/- rats were more susceptible to rTV-Fluc than SD rats with a slower virus clearance rate. Therefore, the rTV-Fluc/SD rats and rTV-Fluc/Rag2-/- rats are suitable visualization models, which recapitulate wild type or immunodeficient populations respectively, for testing human smallpox vaccine and antiviral drugs.

  4. Resistance to Human Respiratory Syncytial Virus (RSV) Infection Induced by Immunization of Cotton Rats with a Recombinant Vaccinia Virus Expressing the RSV G Glycoprotein

    NASA Astrophysics Data System (ADS)

    Elango, Narayanasamy; Prince, Gregory A.; Murphy, Brian R.; Venkatesan, Sundararajan; Chanock, Robert M.; Moss, Bernard

    1986-03-01

    A cDNA copy of the G glycoprotein gene of human respiratory syncytial virus (RSV) was placed under control of a vaccinia virus promoter and inserted into the thymidine kinase locus of the vaccinia virus genome. The recombinant vaccinia virus retained infectivity and expressed a 93-kDa protein that migrated with the authentic RSV G glycoprotein upon polyacrylamide gel electrophoresis. Glycosylation of the expressed protein and transport to the cell surface were demonstrated in the absence of other RSV proteins. Cotton rats that were inoculated intradermally with the infectious recombinant virus produced serum antibody to the G glycoprotein that neutralized RSV in vitro. Furthermore, the vaccinated animals were resistant to lower respiratory tract infection upon intranasal inoculation with RSV and had reduced titers of RSV in the nose.

  5. A cotton rat model of effectors of immunity to respiratory syncytial virus other than serum antibody.

    PubMed

    Piazza, F M; Schmidt, H J; Johnson, S A; Dotson, D L; Darnell, M E; Ottolini, M G; Porter, D D; Prince, G A

    1995-06-01

    A model for studying effectors of immunity to respiratory syncytial virus (RSV) was developed. Paris of inbred cotton rats (Sigmodon hispidus) were joined surgically using the technique of parabiosis. One week later, one animal of each pair was primed intranasally with a small volume of RSV suspension. Fourteen days after priming, both animals of each pair were bled for determination of serum neutralizing antibody titers, and challenged intranasally with a standard dose of RSV suspension. Single, unprimed cotton rats were challenged concomitantly and served as controls. Four days after challenge, all animals were sacrificed for virus titration of nasal tissues and lungs. Parabiosed cotton rats were surgically separated at varying intervals between priming and challenge (days 7, 9, 12, or 14 after priming) or were kept joined until sacrificed (day 18). Significant transfer of nasal and pulmonary immunity from primed to unprimed parabionts began 9 days after priming, gradually increasing through 18 days. Resistance to RSV challenge in spite of low levels of serum neutralizing antibody suggests that non-antibody immunologic mediators were responsible for the transferred immunity. Evidence is presented for three broad categories of RSV immunologic effectors: systemic, local with a transient systemic phase, and local without a systemic phase. These categories are now amenable to further study using the described model.

  6. Species and Interspecies Radioimmunoassays for Rat Type C Virus p30: Interviral Comparisons and Assay of Human Tumor Extracts

    PubMed Central

    Charman, Howard P.; White, Martin H.; Rahman, Rukhsana; Gilden, Raymond V.

    1976-01-01

    The major internal protein, p30, of rat type C virus (RaLV) was purified and utilized to establish intra- and interspecies radioimmunoassays. Three rat viruses were compared in homologous and heterologous intraspecies assays with no evidence of type specificity. The only heterologous viruses to give inhibition in these species assays were the feline (FeLV) and hamster (HaLV) type C viruses; these reactions were incomplete and required high virus concentrations. An interspecies assay using a goat antiserum prepared after sequentially immunizing with FeLV, RD 114, and woolly monkey virus p30's and labeled RaLV p30 was inhibited by all mammalian type C viruses, although preferentially by RaLV, FeLV, and HaLV. Thus, as in a previously reported assay developed with HaLV p30, rat, hamster, and cat p30's seem more closely related to each other than to mouse type C virus p30. High levels of specific antigen were found in all cell lines producing rat virus, whereas embryonic tissues from several rat strains and cell lines considered virus-free based on other tests were negative for p30. Rats bearing tumors containing Moloney murine sarcoma virus (RaLV) did not contain free circulating antibody to RaLV p30. Fifty-one human tumor extracts (including two tumor cell lines) were tested for activity in the RaLV species and 47 in the interspecies assays after Sephadex gel filtration and pooling of material in the 15,000- to 40,000-molecular-weight range. At a sensitivity level of 7 ng/ml (0.7 ng/assay) in the interspecies assay, all human tissues, with one exception, were negative. The one positive result is considered nonspecific based on proteolysis of the labeled antigen. Input tissue protein of the purified tumor extracts averaged 1.9 mg/ml with a range of < 0.025 to 22 mg/ml. Tissues from NIH Swiss mice processed in the same manner were positive in the interspecies assay but negative in the intraspecies RaLV assay. PMID:54444

  7. The anterograde transport of rabies virus in rat sensory dorsal root ganglia neurons.

    PubMed

    Tsiang, H; Lycke, E; Ceccaldi, P E; Ermine, A; Hirardot, X

    1989-08-01

    We have previously described the capacity of neurites extending from cultured rat sensory dorsal root ganglia (DRG) neurons to transport rabies virus through axoplasm in the retrograde direction. Here we report the infection of cultured neurons derived from the DRG and the subsequent anterograde transport of rabies virus from the infected cell somas through the extending neurites to its release into the culture supernatant. Viral transport was monitored by titration of the virus yield in the external compartment. Both early and late transport mechanisms of rabies virions were identified. The first one occurred a few hours post-infection and was undetectable 6 h later, before the initiation of viral replication. The velocity of this first wave of infective virions was in the range of 100 to 400 mm/day. The early viral transport was probably the result of a direct translocation of infective virions from the somatic site of entry to the neuritic extensions and subsequent release into the culture medium without replication in the cellular perikaryon. The second virus transport peak was detected 48 h post-infection. In this case, the virions detected in the neuritic compartment were presumably the progeny of the inoculated virus which had replicated in the perikaryon before the viral transport occurs. Using a four-compartment culture device we were able to demonstrate, simultaneously, retrograde and anterograde transport of the virus. The presence of antirabies serum in contact with the exposed neurites did not inhibit either the retrograde or the anterograde transport mechanisms. The viral release from the neuritic extensions after the fast anterograde transport was evaluated to be in the range of 150 to 300 infectious virions per bundle of neurites per day.

  8. Development of Acquired Immunity following Repeated Respiratory Syncytial Virus Infections in Cotton Rats.

    PubMed

    Yamaji, Yoshiaki; Yasui, Yosuke; Nakayama, Tetsuo

    2016-01-01

    Respiratory syncytial virus (RSV) infections occur every year worldwide. Most infants are infected with RSV by one year of age and are reinfected because immune responses after the first infection are too weak to protect against subsequent infections. In the present study, immune responses against RSV were investigated in order to obtain a better understanding of repetitive RSV infections in cotton rats. No detectable neutralizing antibody (NT) was developed after the first infection, and the second infection was not prevented. The results of histological examinations revealed severe inflammation, viral antigens were detected around bronchial epithelial cells, and infectious viruses were recovered from lung homogenates. Following the second infection neutralizing antibodies were significantly elevated, and CD8+ cells were activated in response to RSV-F253-265. No viral antigens was detected thereafter in lung tissues and infectious viruses were not recovered. Similar results were obtained in the present study using the subgroups A and B. These results support the induction of humoral and cellular immune responses following repetitive infections with RSV; however, these responses were insufficient to eliminate viruses in the first and second infections. PMID:27224021

  9. Neuronal changes induced by Varicella Zoster Virus in a rat model of Postherpetic Neuralgia

    PubMed Central

    Guedon, Jean-Marc G.; Yee, Michael B.; Zhang, Mingdi; Harvey, Stephen A. K.; Goins, William F.; Kinchington, Paul R.

    2015-01-01

    A significant fraction of patients with herpes zoster, caused by varicella zoster virus (VZV), experience chronic pain termed postherpetic neuralgia (PHN). VZV-inoculated rats develop prolonged nocifensive behaviors and serve as a model of PHN. We demonstrate that primary rat cultures show a post-entry block for VZV replication, suggesting the rat is not fully permissive. However, footpads of VZV infected animals show reduced peripheral innervation and innervating dorsal root ganglia (DRG) contained VZV DNA and transcripts of candidate immediate early and early genes. The VZV-infected DRG showed changes in host gene expression patterns, with 84 up-regulated and 116 down-regulated genes seen in gene array studies. qRT-PCR validated the modulation of nociception-associated genes Ntrk2, Trpv1, and Calca (CGRP). The data suggests that VZV inoculation of the rat results in a single round, incomplete infection that is sufficient to induce pain behaviors, and this involves infection of and changes induced in neuronal populations. PMID:25880108

  10. Mapping a Major Gene for Resistance to Rift Valley Fever Virus in Laboratory Rats.

    PubMed

    Busch, Catherine M; Callicott, Ralph J; Peters, Clarence J; Morrill, John C; Womack, James E

    2015-01-01

    The Rift Valley Fever virus (RVFV) presents an epidemic and epizootic threat in sub-Saharan Africa, Egypt, and the Arabian Peninsula, and has furthermore recently gained attention as a potential weapon of bioterrorism due to its ability to infect both livestock and humans. Inbred rat strains show similar characteristic responses to the disease as humans and livestock, making them a suitable model species. Previous studies had indicated differences in susceptibility to RVFV hepatic disease among various rat strains, including a higher susceptibility of Wistar-Furth (WF) compared to a more resistant Lewis (LEW) strain. Further study revealed that this resistance trait exhibits the pattern of a major dominant gene inherited in Mendelian fashion. A genome scan of a congenic WF.LEW strain, created from the susceptible WF and resistant LEW strains and itself resistant to infection with RVFV, revealed 2 potential regions for the location of the gene, 1 on chromosome 3 and the other on chromosome 9. Through backcrossing of WF.LEW rats to WF rats, genotyping offspring using SNPs and microsatellites, and viral challenges of 3 N1 litters, we have mapped the gene to the distal end of chromosome 3. PMID:26546799

  11. Marked genomic heterogeneity of rat hepatitis E virus strains in Indonesia demonstrated on a full-length genome analysis.

    PubMed

    Mulyanto; Suparyatmo, Joseph Benedictus; Andayani, I Gusti Ayu Sri; Khalid; Takahashi, Masaharu; Ohnishi, Hiroshi; Jirintai, Suljid; Nagashima, Shigeo; Nishizawa, Tsutomu; Okamoto, Hiroaki

    2014-01-22

    Rat hepatitis E virus (HEV) strains have recently been isolated in several areas of Germany, Vietnam, the United States, Indonesia and China. However, genetic information regarding these rat HEV strains is limited. A total of 369 wild rats (Rattus rattus) captured in Central Java (Solo) and on Lombok Island, Indonesia were tested for the presence of rat HEV-specific antibodies and RNA. Overall, 137 rats (37.1%) tested positive for rat anti-HEV antibodies, while 97 (26.3%) had rat HEV RNA detectable on reverse transcription-PCR with primers targeting the ORF1-ORF2 junctional region. The 97 HEV strains recovered from these viremic rats were 76.3-100% identical to each other in an 840-nucleotide sequence and 75.4-88.4% identical to the rat HEV strains reported in Germany and Vietnam. Five representative Indonesian strains, one from each of five phylogenetic clusters, whose entire genomic sequence was determined, were segregated into three genetic groups (a German type, Vietnamese type and novel type), which differed from each other by 19.5-23.5 (22.0 ± 1.7)% over the entire genome. These results suggest the presence of at least three genetic groups of rat HEV and indicate the circulation of polyphyletic strains of rat HEV belonging to three distinct genetic groups in Indonesia.

  12. Marked genomic heterogeneity of rat hepatitis E virus strains in Indonesia demonstrated on a full-length genome analysis.

    PubMed

    Mulyanto; Suparyatmo, Joseph Benedictus; Andayani, I Gusti Ayu Sri; Khalid; Takahashi, Masaharu; Ohnishi, Hiroshi; Jirintai, Suljid; Nagashima, Shigeo; Nishizawa, Tsutomu; Okamoto, Hiroaki

    2014-01-22

    Rat hepatitis E virus (HEV) strains have recently been isolated in several areas of Germany, Vietnam, the United States, Indonesia and China. However, genetic information regarding these rat HEV strains is limited. A total of 369 wild rats (Rattus rattus) captured in Central Java (Solo) and on Lombok Island, Indonesia were tested for the presence of rat HEV-specific antibodies and RNA. Overall, 137 rats (37.1%) tested positive for rat anti-HEV antibodies, while 97 (26.3%) had rat HEV RNA detectable on reverse transcription-PCR with primers targeting the ORF1-ORF2 junctional region. The 97 HEV strains recovered from these viremic rats were 76.3-100% identical to each other in an 840-nucleotide sequence and 75.4-88.4% identical to the rat HEV strains reported in Germany and Vietnam. Five representative Indonesian strains, one from each of five phylogenetic clusters, whose entire genomic sequence was determined, were segregated into three genetic groups (a German type, Vietnamese type and novel type), which differed from each other by 19.5-23.5 (22.0 ± 1.7)% over the entire genome. These results suggest the presence of at least three genetic groups of rat HEV and indicate the circulation of polyphyletic strains of rat HEV belonging to three distinct genetic groups in Indonesia. PMID:24231359

  13. Neural-endocrine mechanisms of respiratory syncytial virus-associated asthma in a rat model.

    PubMed

    Li, Q G; Wu, X R; Li, X Z; Yu, J; Xia, Y; Wang, A P; Wang, J

    2012-08-24

    We examined the underlying neural-endocrine mechanisms of asthma associated with respiratory syncytial virus infection. Thirty Sprague-Dawley rats were randomly divided into control group, respiratory syncytial virus (RSV) group, and anti-nerve growth factor (NGF) IgG group. An RSV infection model was established by nasal drip once a week. In the anti-NGF antibody intervention group, each rat was given an intraperitoneal injection of anti-NGF IgG 3 h before RSV infection. Optical microscopy and transmission electron microscopy were used to observe the structural changes in adrenal medulla cells. Changes in adrenaline and norepinephrine in serum were detected by ELISA. NGF expression was assayed by immunohistochemistry. Expression differences in synaptophysin mRNA were detected by RT-PCR. Transmission electron microscopy displayed widened adrenal medulla intercellular spaces, reduced chromaffin particle concentration, and increased mitochondria in the RSV infection group. At the same time, NGF expression was increased in the RSV infection group significantly. In addition, the adrenaline concentration was significantly decreased compared with the control and anti-NGF antibody groups. Synaptophysin mRNA expression was significantly increased in the RSV infection and anti-NGF antibody groups. However, compared with the RSV infection group, synaptophysin mRNA expression was significantly decreased in the anti-NGF antibody group. We conclude that RSV infection could induce adrenal medulla cell differentiation to nerve cells by over-expression of NGF, resulting in the decreased endocrine function found in asthma progression.

  14. Respiratory syncytial virus alters electrophysiologic properties in cotton rat airway epithelium.

    PubMed

    Cloutier, M M; Wong, D; Ogra, P L

    1989-01-01

    The effect of respiratory syncytial virus (RSV) infection on the electrophysiologic properties of the airway epithelium was studied in tracheas obtained from cotton rats, after in vivo exposure to the virus. RSV infection was documented by tissue culture infectivity and immunofluorescent antibody techniques. Light microscopic studies of the tracheas 72 hours after exposure to RSV revealed normal epithelial morphology. RSV infection produced a 28% decrease in short-circuit current (Isc) and an almost 100% increase in tissue resistance. The decrease in Isc was partially attributed to a decrease in Cl secretion, while the increase in tissue resistance was associated with significant restriction to sodium and chloride movement through the paracellular pathway in RSV-infected tracheas. We conclude from these studies that RSV infection in the cotton rat trachea produces significant changes in active and passive ion flows. Alterations in ion transport across the airway epithelium may result in changes in secondary water transport across the airways and may contribute to the pathophysiology of RSV bronchiolitis and other locally invasive mucosal viral infections in children.

  15. Tick-Borne Encephalitis Virus Infects Rat Astrocytes but Does Not Affect Their Viability

    PubMed Central

    Potokar, Maja; Korva, Miša; Jorgačevski, Jernej; Avšič-Županc, Tatjana; Zorec, Robert

    2014-01-01

    Tick-borne encephalitis virus (TBEV) causes one of the most dangerous human neuroinfections in Europe and Asia. To infect neurons it must cross the blood-brain-barrier (BBB), and presumably also cells adjacent to the BBB, such as astrocytes, the most abundant glial cell type. However, the knowledge about the viral infection of glial cells is fragmental. Here we studied whether TBEV infects rat astrocytes. Rats belong to an animal group serving as a TBEV amplifying host. We employed high resolution quantitative fluorescence microscopy to investigate cell entry and cytoplasmic mobility of TBEV particles along with the effect on the cell cytoskeleton and cell survival. We report that infection of astrocytes with TBEV increases with time of exposure to TBEV and that with post-infection time TBEV particles gained higher mobility. After several days of infection actin cytoskeleton was affected, but cell survival was unchanged, indicating that rat astrocytes resist TBEV-mediated cell death, as reported for other mammalian cells. Therefore, astrocytes may present an important pool of dormant TBEV infections and a new target for therapeutic intervention. PMID:24465969

  16. Adeno-associated virus vector serotypes mediate sustained correction of bilirubin UDP glucuronosyltransferase deficiency in rats.

    PubMed

    Seppen, Jurgen; Bakker, Conny; de Jong, Berry; Kunne, Cindy; van den Oever, Karin; Vandenberghe, Kristin; de Waart, Rudi; Twisk, Jaap; Bosma, Piter

    2006-06-01

    Crigler-Najjar (CN) patients have no bilirubin UDP glucuronosyltransferase (UGT1A1) activity and suffer brain damage because of bilirubin toxicity. Vectors based on adeno-associated virus (AAV) serotype 2 transduce liver cells with relatively low efficiency. Recently, AAV serotypes 1, 6, and 8 have been shown to be more efficient for liver cell transduction. We compared AAV serotypes 1, 2, 6, and 8 for correction of UGT1A1 deficiency in the Gunn rat model of CN disease. Adult Gunn rats were injected with CMV-UGT1A1 AAV vectors. Serum bilirubin was decreased over the first year by 64% for AAV1, 16% for AAV2, 25% for AAV6, and 35% for AAV8. Antibodies to UGT1A1 were detected after injection of all AAV serotypes. An AAV1 UGT1A1 vector with the liver-specific albumin promoter corrected serum bilirubin levels but did not induce UGT1A1 antibodies. Two years after injection of AAV vectors all animals had large lipid deposits in the liver. These lipid deposits were not seen in age-matched control animals. AAV1 vectors are promising candidates for CN gene therapy because they can mediate a reduction in serum bilirubin levels in Gunn rats that would be therapeutic in humans. PMID:16581301

  17. Subchronic Immunotoxicity Assessment of Genetically Modified Virus-Resistant Papaya in Rats.

    PubMed

    Lin, Hsin-Tang; Lee, Wei-Cheng; Tsai, Yi-Ting; Wu, Jhaol-Huei; Yen, Gow-Chin; Yeh, Shyi-Dong; Cheng, Ying-Huey; Chang, Shih-Chieh; Liao, Jiunn-Wang

    2016-07-27

    Papaya is an important fruit that provides a variety of vitamins with nutritional value and also holds some pharmacological properties, including immunomodulation. Genetically modified (GM) papaya plants resistant to Papaya ringspot virus (PRSV) infection have been generated by cloning the coat protein gene of the PRSV which can be used as a valuable strategy to fight PRSV infection and to increase papaya production. In order to assess the safety of GM papaya as a food, this subchronic study was conducted to assess the immunomodulatory responses of the GM papaya line 823-2210, when compared with its parent plant of non-GM papaya, Tainung-2 (TN-2), in Sprague-Dawley (SD) rats. Both non-GM and GM 823-2210 papaya fruits at low (1 g/kg bw) and high (2 g/kg bw) dosages were administered via daily oral gavage to male and female rats consecutively for 90 days. Immunophenotyping, mitogen-induced splenic cell proliferation, antigen-specific antibody response, and histopathology of the spleen and thymus were evaluated at the end of the experiment. Results of immunotoxicity assays revealed no consistent difference between rats fed for 90 days with GM 823-2210 papaya fruits, as opposed to those fed non-GM TN-2 papaya fruits, suggesting that with regard to immunomodulatory responses, GM 823-2210 papaya fruits maintain substantial equivalence to fruits of their non-GM TN-2 parent. PMID:27396727

  18. Subchronic Immunotoxicity Assessment of Genetically Modified Virus-Resistant Papaya in Rats.

    PubMed

    Lin, Hsin-Tang; Lee, Wei-Cheng; Tsai, Yi-Ting; Wu, Jhaol-Huei; Yen, Gow-Chin; Yeh, Shyi-Dong; Cheng, Ying-Huey; Chang, Shih-Chieh; Liao, Jiunn-Wang

    2016-07-27

    Papaya is an important fruit that provides a variety of vitamins with nutritional value and also holds some pharmacological properties, including immunomodulation. Genetically modified (GM) papaya plants resistant to Papaya ringspot virus (PRSV) infection have been generated by cloning the coat protein gene of the PRSV which can be used as a valuable strategy to fight PRSV infection and to increase papaya production. In order to assess the safety of GM papaya as a food, this subchronic study was conducted to assess the immunomodulatory responses of the GM papaya line 823-2210, when compared with its parent plant of non-GM papaya, Tainung-2 (TN-2), in Sprague-Dawley (SD) rats. Both non-GM and GM 823-2210 papaya fruits at low (1 g/kg bw) and high (2 g/kg bw) dosages were administered via daily oral gavage to male and female rats consecutively for 90 days. Immunophenotyping, mitogen-induced splenic cell proliferation, antigen-specific antibody response, and histopathology of the spleen and thymus were evaluated at the end of the experiment. Results of immunotoxicity assays revealed no consistent difference between rats fed for 90 days with GM 823-2210 papaya fruits, as opposed to those fed non-GM TN-2 papaya fruits, suggesting that with regard to immunomodulatory responses, GM 823-2210 papaya fruits maintain substantial equivalence to fruits of their non-GM TN-2 parent.

  19. Seoul virus in the Brown Rat ( Rattus norvegicus ) from Ürümqi, Xinjiang, Northwest of China.

    PubMed

    Guo, Gang; Sheng, Jinliang; Wu, Xiran; Wang, Yuanzhi; Guo, Liping; Zhang, Xun; Yao, Hua

    2016-07-01

    Hantavirus infections among human populations are linked to the geographic distribution of the host rodents that carry the viruses. To determine the presence and distribution of hantaviruses in the northern region of Xinjiang Uygur Autonomous Region (XUAR), northwestern China, 844 rodents were captured from five locations in four dissimilar habitats during 2010-14 and examined for Hantavirus infection. Hantavirus nucleic acids were firstly detected in the brown rat ( Rattus norvegicus ) from Ürümqi, China, indicating that the Hantavirus was transmitted into Ürümqi in XUAR and circulated by the brown rat. Our results suggest that the brown rat may act as a natural reservoir for the virus in XUAR.

  20. Seoul virus in the Brown Rat ( Rattus norvegicus ) from Ürümqi, Xinjiang, Northwest of China.

    PubMed

    Guo, Gang; Sheng, Jinliang; Wu, Xiran; Wang, Yuanzhi; Guo, Liping; Zhang, Xun; Yao, Hua

    2016-07-01

    Hantavirus infections among human populations are linked to the geographic distribution of the host rodents that carry the viruses. To determine the presence and distribution of hantaviruses in the northern region of Xinjiang Uygur Autonomous Region (XUAR), northwestern China, 844 rodents were captured from five locations in four dissimilar habitats during 2010-14 and examined for Hantavirus infection. Hantavirus nucleic acids were firstly detected in the brown rat ( Rattus norvegicus ) from Ürümqi, China, indicating that the Hantavirus was transmitted into Ürümqi in XUAR and circulated by the brown rat. Our results suggest that the brown rat may act as a natural reservoir for the virus in XUAR. PMID:27258409

  1. Further assessment of Monkeypox Virus infection in Gambian pouched rats (Cricetomys gambianus) using in vivo bioluminescent imaging

    USGS Publications Warehouse

    Falendysz, Elizabeth; Lopera, Juan G.; Faye Lorenzsonn,; Salzer, Johanna S.; Hutson, Christina L.; Doty, Jeffrey; Gallardo-Romero, Nadia; Carroll, Darin S.; Osorio, Jorge E.; Rocke, Tonie E.

    2015-01-01

    Monkeypox is a zoonosis clinically similar to smallpox in humans. Recent evidence has shown a potential risk of increased incidence in central Africa. Despite attempts to isolate the virus from wild rodents and other small mammals, no reservoir host has been identified. In 2003,Monkeypox virus (MPXV) was accidentally introduced into the U.S. via the pet trade and was associated with the Gambian pouched rat (Cricetomys gambianus). Therefore, we investigated the potential reservoir competence of the Gambian pouched rat for MPXV by utilizing a combination of in vivo and in vitro methods. We inoculated three animals by the intradermal route and three animals by the intranasal route, with one mock-infected control for each route. Bioluminescent imaging (BLI) was used to track replicating virus in infected animals and virological assays (e.g. real time PCR, cell culture) were used to determine viral load in blood, urine, ocular, nasal, oral, and rectal swabs. Intradermal inoculation resulted in clinical signs of monkeypox infection in two of three animals. One severely ill animal was euthanized and the other affected animal recovered. In contrast, intranasal inoculation resulted in subclinical infection in all three animals. All animals, regardless of apparent or inapparent infection, shed virus in oral and nasal secretions. Additionally, BLI identified viral replication in the skin without grossly visible lesions. These results suggest that Gambian pouched rats may play an important role in transmission of the virus to humans, as they are hunted for consumption and it is possible for MPXV-infected pouched rats to shed infectious virus without displaying overt clinical signs.

  2. Further Assessment of Monkeypox Virus Infection in Gambian Pouched Rats (Cricetomys gambianus) Using In Vivo Bioluminescent Imaging

    PubMed Central

    Falendysz, Elizabeth A.; Lopera, Juan G.; Lorenzsonn, Faye; Salzer, Johanna S.; Hutson, Christina L.; Doty, Jeffrey; Gallardo-Romero, Nadia; Carroll, Darin S.; Osorio, Jorge E.; Rocke, Tonie E.

    2015-01-01

    Monkeypox is a zoonosis clinically similar to smallpox in humans. Recent evidence has shown a potential risk of increased incidence in central Africa. Despite attempts to isolate the virus from wild rodents and other small mammals, no reservoir host has been identified. In 2003, Monkeypox virus (MPXV) was accidentally introduced into the U.S. via the pet trade and was associated with the Gambian pouched rat (Cricetomys gambianus). Therefore, we investigated the potential reservoir competence of the Gambian pouched rat for MPXV by utilizing a combination of in vivo and in vitro methods. We inoculated three animals by the intradermal route and three animals by the intranasal route, with one mock-infected control for each route. Bioluminescent imaging (BLI) was used to track replicating virus in infected animals and virological assays (e.g. real time PCR, cell culture) were used to determine viral load in blood, urine, ocular, nasal, oral, and rectal swabs. Intradermal inoculation resulted in clinical signs of monkeypox infection in two of three animals. One severely ill animal was euthanized and the other affected animal recovered. In contrast, intranasal inoculation resulted in subclinical infection in all three animals. All animals, regardless of apparent or inapparent infection, shed virus in oral and nasal secretions. Additionally, BLI identified viral replication in the skin without grossly visible lesions. These results suggest that Gambian pouched rats may play an important role in transmission of the virus to humans, as they are hunted for consumption and it is possible for MPXV-infected pouched rats to shed infectious virus without displaying overt clinical signs. PMID:26517839

  3. Further Assessment of Monkeypox Virus Infection in Gambian Pouched Rats (Cricetomys gambianus) Using In Vivo Bioluminescent Imaging.

    PubMed

    Falendysz, Elizabeth A; Lopera, Juan G; Lorenzsonn, Faye; Salzer, Johanna S; Hutson, Christina L; Doty, Jeffrey; Gallardo-Romero, Nadia; Carroll, Darin S; Osorio, Jorge E; Rocke, Tonie E

    2015-01-01

    Monkeypox is a zoonosis clinically similar to smallpox in humans. Recent evidence has shown a potential risk of increased incidence in central Africa. Despite attempts to isolate the virus from wild rodents and other small mammals, no reservoir host has been identified. In 2003, Monkeypox virus (MPXV) was accidentally introduced into the U.S. via the pet trade and was associated with the Gambian pouched rat (Cricetomys gambianus). Therefore, we investigated the potential reservoir competence of the Gambian pouched rat for MPXV by utilizing a combination of in vivo and in vitro methods. We inoculated three animals by the intradermal route and three animals by the intranasal route, with one mock-infected control for each route. Bioluminescent imaging (BLI) was used to track replicating virus in infected animals and virological assays (e.g. real time PCR, cell culture) were used to determine viral load in blood, urine, ocular, nasal, oral, and rectal swabs. Intradermal inoculation resulted in clinical signs of monkeypox infection in two of three animals. One severely ill animal was euthanized and the other affected animal recovered. In contrast, intranasal inoculation resulted in subclinical infection in all three animals. All animals, regardless of apparent or inapparent infection, shed virus in oral and nasal secretions. Additionally, BLI identified viral replication in the skin without grossly visible lesions. These results suggest that Gambian pouched rats may play an important role in transmission of the virus to humans, as they are hunted for consumption and it is possible for MPXV-infected pouched rats to shed infectious virus without displaying overt clinical signs. PMID:26517839

  4. Hepatitis B virus e antigen induces activation of rat hepatic stellate cells

    SciTech Connect

    Zan, Yanlu; Zhang, Yuxia; Tien, Po

    2013-06-07

    Highlights: •HBeAg expression in HSCs induced production of ECM protein and liver fibrotic markers. •The activation and proliferation of HSCs were mediated by TGF-β. •HBeAg protein purified from cell medium directly activated HSCs. -- Abstract: Chronic hepatitis B virus infection is a major cause of hepatic fibrosis, leading to liver cirrhosis and hepatocellular carcinoma. Hepatitis B virus e antigen (HBeAg) is an accessory protein of HBV, not required for viral replication but important for natural infection in vivo. Hepatic stellate cells (HSCs) are the major producers of excessive extracellular matrix during liver fibrogenesis. Therefore, we examined the influence of HBeAg on HSCs. The rat HSC line HSC-T6 was transfected with HBeAg plasmids, and expression of α-smooth muscle actin, collagen I, transforming growth factor-β1 (TGF-β), and tissue inhibitors of metalloproteinase 1 (TIMP-1) was investigated by quantitative real-time PCR. The proliferation of HSCs was determined by MTS analysis. HBeAg transduction induced up-regulation of these fibrogenic genes and proliferation of HSCs. We found that HBeAg induced TGF-β secretion in HSCs, and the activation of HSCs was prevented by a neutralizing anti-TGF-β antibody. Depletion and addition of HBeAg protein in conditioned medium from HSC-T6 cells transduced with HBeAg indicated that HBeAg directly induced the activation and proliferation of rat primary HSCs. Taken together, HBeAg induces the activation and proliferation of HSCs, mainly mediated by TGF-β, and HBeAg protein purified from cell medium can directly activate HSCs.

  5. Systemic immunoprophylaxis of nasal respiratory syncytial virus infection in cotton rats.

    PubMed

    Sami, I R; Piazza, F M; Johnson, S A; Darnell, M E; Ottolini, M G; Hemming, V G; Prince, G A

    1995-02-01

    The cotton rat model was used to test whether systemically administered immunoglobulin could protect nasal tissues against low challenge doses of respiratory syncytial virus (RSV). Animals were pretreated by intraperitoneal injection of human immunoglobulin with moderate (1:2226) or high (1:15,000) neutralizing antibody titers to RSV (day 0), challenged intranasally with RSV Long at doses ranging from 10(1) to 10(5) pfu (day 1), and sacrificed for virus titration (day 5). Pretreatment with moderate-titer immunoglobulin effected complete or near complete nasal protection against low to moderate (10(1)-10(3) pfu) RSV challenge doses and a significant reduction in nasal RSV titers at high (10(4)-10(5) pfu) challenge doses. Pretreatment with high-titer immunoglobulin effected near complete nasal protection at an RSV challenge dose of 10(3) pfu and highly significant and significant reductions in nasal RSV titers at challenge doses of 10(4) and 10(5) pfu, respectively. Immunoprophylaxis effected complete or near complete pulmonary protection at all RSV challenge doses.

  6. Social status does not predict responses to Seoul virus infection or reproductive success among male Norway rats.

    PubMed

    Hinson, Ella R; Hannah, Michele F; Norris, Douglas E; Glass, Gregory E; Klein, Sabra L

    2006-03-01

    Trade-offs exist among life history strategies that are used to increase survival and reproduction; such that, males that engage in more competitive behaviors may be more susceptible to infection. Hantaviruses are transmitted horizontally between rodents through the passage of virus in saliva during wounding and male rodents are more likely to be infected with hantaviruses than females. To determine whether a trade-off exists between dominance and susceptibility to Seoul virus infection, male Long Evans rats were group housed (3/cage) with a female rat and aggressive and subordinate behaviors were monitored during a 10 day group housing condition. After behavioral testing, males were individually housed, inoculated with Seoul virus, and blood, saliva, and fecal samples were collected. Dominant males initiated more aggressive encounters than subordinate males. Dominant and subordinate males, however, had similar steroid hormone concentrations, anti-Seoul virus IgG responses, and weight gain over the course of infection. A similar proportion of dominant and subordinate males shed virus in saliva and feces during infection. Using microsatellite DNA markers paternity was assigned to pups derived during the group housing period. In contrast to our initial hypothesis, dominant and subordinate males sired a similar percentage of pups. Taken together, host social status may not predict reproductive success or susceptibility to hantaviruses in rodent reservoir populations.

  7. Intranasal nanoemulsion-based inactivated respiratory syncytial virus vaccines protect against viral challenge in cotton rats

    PubMed Central

    O'Konek, Jessica J; Makidon, Paul E; Landers, Jeffrey J; Cao, Zhengyi; Malinczak, Carrie-Anne; Pannu, Jessie; Sun, Jennifer; Bitko, Vira; Ciotti, Susan; Hamouda, Tarek; Wojcinski, Zbigniew W; Lukacs, Nicholas W; Fattom, Ali; Baker, James R

    2015-01-01

    Respiratory Syncytial Virus is a leading cause of bronchiolitis and pneumonia in infants, the elderly and individuals with compromised immune systems. Despite decades of research, there is currently no available vaccine for RSV. Our group has previously demonstrated that intranasal immunization of mice with RSV inactivated by and adjuvanted with W805EC nanoemulsion elicits robust humoral and cellular immune responses, resulting in protection against RSV infection. This protection was achieved without the induction of airway hyper-reactivity or a Th2-skewed immune response. The cotton rat Sigmodon hispidus has been used for years as an excellent small animal model of RSV disease. Thus, we extended these rodent studies to the more permissive cotton rat model. Intranasal immunization of the nanoemulsion-adjuvanted RSV vaccines induced high antibody titers and a robust Th1-skewed cellular response. Importantly, vaccination provided sterilizing cross-protective immunity against a heterologous RSV challenge and did not induce marked or severe histological effects or eosinophilia in the lung after viral challenge. Overall, these data demonstrate that nanoemulsion-formulated whole RSV vaccines are both safe and effective for immunization in multiple animal models. PMID:26307915

  8. Intranasal nanoemulsion-based inactivated respiratory syncytial virus vaccines protect against viral challenge in cotton rats.

    PubMed

    O'Konek, Jessica J; Makidon, Paul E; Landers, Jeffrey J; Cao, Zhengyi; Malinczak, Carrie-Anne; Pannu, Jessie; Sun, Jennifer; Bitko, Vira; Ciotti, Susan; Hamouda, Tarek; Wojcinski, Zbigniew W; Lukacs, Nicholas W; Fattom, Ali; Baker, James R

    2015-01-01

    Respiratory Syncytial Virus is a leading cause of bronchiolitis and pneumonia in infants, the elderly and individuals with compromised immune systems. Despite decades of research, there is currently no available vaccine for RSV. Our group has previously demonstrated that intranasal immunization of mice with RSV inactivated by and adjuvanted with W805EC nanoemulsion elicits robust humoral and cellular immune responses, resulting in protection against RSV infection. This protection was achieved without the induction of airway hyper-reactivity or a Th2-skewed immune response. The cotton rat Sigmodon hispidus has been used for years as an excellent small animal model of RSV disease. Thus, we extended these rodent studies to the more permissive cotton rat model. Intranasal immunization of the nanoemulsion-adjuvanted RSV vaccines induced high antibody titers and a robust Th1-skewed cellular response. Importantly, vaccination provided sterilizing cross-protective immunity against a heterologous RSV challenge and did not induce marked or severe histological effects or eosinophilia in the lung after viral challenge. Overall, these data demonstrate that nanoemulsion-formulated whole RSV vaccines are both safe and effective for immunization in multiple animal models. PMID:26307915

  9. Seoul virus enhances regulatory and reduces proinflammatory responses in male Norway rats.

    PubMed

    Easterbrook, Judith D; Klein, Sabra L

    2008-07-01

    Zoonotic pathogens, including hantaviruses, are maintained in the environment by causing persistent infection in the absence of disease in their reservoir hosts. Spillover of hantaviruses to humans can cause severe disease that is mediated by excessive proinflammatory responses. The mechanisms mediating hantaviral persistence in rodent reservoirs remain largely unknown. Male Norway rats were inoculated with their species-specific hantavirus, Seoul virus (SEOV), and viral RNA, cytokine, and chemokine responses were evaluated in spleen and lung tissue. More viral RNA was detectable in the lungs than spleen, with copies of SEOV peaking 15-30 days post-inoculation (p.i.) and persisting for 60 days p.i. In the lungs, the expression and production of proinflammatory mediators (i.e., IL-1beta, IL-6, TNF-alpha, IFN-gamma, CCL5, CCL2, CX3CL1, CXCL10, VCAM, VEGF, and NOS2) remained at or below baseline throughout SEOV infection; whereas, regulatory factors, including TGF-beta and FoxP3 were elevated. Conversely, in the spleen, proinflammatory responses were induced while regulatory responses remained unchanged during infection. To determine whether reduced proinflammatory responses mediate hantavirus persistence in the lungs, male rats were administered rIL-1beta or vehicle for 30 days during SEOV infection. SEOV persistence and shedding were not affected by IL-1beta treatment. Proinflammatory responses were elevated in rIL-1beta-treated rats, but remained within physiological levels, suggesting that supra-physiological concentrations may be necessary for viral clearance at the cost of causing disease. Elevated regulatory responses may suppress excessively high proinflammatory responses at a site of elevated SEOV replication to contribute to viral persistence and prevent proinflammatory-mediated disease in reservoir hosts.

  10. Laboratory Investigations of African Pouched Rats (Cricetomys gambianus) as a Potential Reservoir Host Species for Monkeypox Virus

    PubMed Central

    Hutson, Christina L.; Nakazawa, Yoshinori J.; Self, Joshua; Olson, Victoria A.; Regnery, Russell L.; Braden, Zachary; Weiss, Sonja; Malekani, Jean; Jackson, Eddie; Tate, Mallory; Karem, Kevin L.; Rocke, Tonie E.; Osorio, Jorge E.; Damon, Inger K.; Carroll, Darin S.

    2015-01-01

    Abstract Monkeypox is a zoonotic disease endemic to central and western Africa, where it is a major public health concern. Although Monkeypox virus (MPXV) and monkeypox disease in humans have been well characterized, little is known about its natural history, or its maintenance in animal populations of sylvatic reservoir(s). In 2003, several species of rodents imported from Ghana were involved in a monkeypox outbreak in the United States with individuals of three African rodent genera (Cricetomys, Graphiurus, Funisciurus) shown to be infected with MPXV. Here, we examine the course of MPXV infection in Cricetomys gambianus (pouched Gambian rats) and this rodent species’ competence as a host for the virus. We obtained ten Gambian rats from an introduced colony in Grassy Key, Florida and infected eight of these via scarification with a challenge dose of 4X104 plaque forming units (pfu) from either of the two primary clades of MPXV: Congo Basin (C-MPXV: n = 4) or West African (W-MPXV: n = 4); an additional 2 animals served as PBS controls. Viral shedding and the effect of infection on activity and physiological aspects of the animals were measured. MPXV challenged animals had significantly higher core body temperatures, reduced activity and increased weight loss than PBS controls. Viable virus was found in samples taken from animals in both experimental groups (C-MPXV and W-MPXV) between 3 and 27 days post infection (p.i.) (up to 1X108 pfu/ml), with viral DNA found until day 56 p.i. The results from this work show that Cricetomys gambianus (and by inference, probably the closely related species, Cricetomys emini) can be infected with MPXV and shed viable virus particles; thus suggesting that these animals may be involved in the maintenance of MPXV in wildlife mammalian populations. More research is needed to elucidate the epidemiology of MPXV and the role of Gambian rats and other species. PMID:26517724

  11. Laboratory Investigations of African Pouched Rats (Cricetomys gambianus) as a Potential Reservoir Host Species for Monkeypox Virus.

    PubMed

    Hutson, Christina L; Nakazawa, Yoshinori J; Self, Joshua; Olson, Victoria A; Regnery, Russell L; Braden, Zachary; Weiss, Sonja; Malekani, Jean; Jackson, Eddie; Tate, Mallory; Karem, Kevin L; Rocke, Tonie E; Osorio, Jorge E; Damon, Inger K; Carroll, Darin S

    2015-01-01

    Monkeypox is a zoonotic disease endemic to central and western Africa, where it is a major public health concern. Although Monkeypox virus (MPXV) and monkeypox disease in humans have been well characterized, little is known about its natural history, or its maintenance in animal populations of sylvatic reservoir(s). In 2003, several species of rodents imported from Ghana were involved in a monkeypox outbreak in the United States with individuals of three African rodent genera (Cricetomys, Graphiurus, Funisciurus) shown to be infected with MPXV. Here, we examine the course of MPXV infection in Cricetomys gambianus (pouched Gambian rats) and this rodent species' competence as a host for the virus. We obtained ten Gambian rats from an introduced colony in Grassy Key, Florida and infected eight of these via scarification with a challenge dose of 4X104 plaque forming units (pfu) from either of the two primary clades of MPXV: Congo Basin (C-MPXV: n = 4) or West African (W-MPXV: n = 4); an additional 2 animals served as PBS controls. Viral shedding and the effect of infection on activity and physiological aspects of the animals were measured. MPXV challenged animals had significantly higher core body temperatures, reduced activity and increased weight loss than PBS controls. Viable virus was found in samples taken from animals in both experimental groups (C-MPXV and W-MPXV) between 3 and 27 days post infection (p.i.) (up to 1X108 pfu/ml), with viral DNA found until day 56 p.i. The results from this work show that Cricetomys gambianus (and by inference, probably the closely related species, Cricetomys emini) can be infected with MPXV and shed viable virus particles; thus suggesting that these animals may be involved in the maintenance of MPXV in wildlife mammalian populations. More research is needed to elucidate the epidemiology of MPXV and the role of Gambian rats and other species. PMID:26517724

  12. Combined virus-like particle and fusion protein-encoding DNA vaccination of cotton rats induces protection against respiratory syncytial virus without causing vaccine-enhanced disease.

    PubMed

    Hwang, Hye Suk; Lee, Young-Tae; Kim, Ki-Hye; Park, Soojin; Kwon, Young-Man; Lee, Youri; Ko, Eun-Ju; Jung, Yu-Jin; Lee, Jong Seok; Kim, Yu-Jin; Lee, Yu-Na; Kim, Min-Chul; Cho, Minkyoung; Kang, Sang-Moo

    2016-07-01

    A safe and effective vaccine against respiratory syncytial virus (RSV) should confer protection without causing vaccine-enhanced disease. Here, using a cotton rat model, we investigated the protective efficacy and safety of an RSV combination vaccine composed of F-encoding plasmid DNA and virus-like particles containing RSV fusion (F) and attachment (G) glycoproteins (FFG-VLP). Cotton rats with FFG-VLP vaccination controlled lung viral replication below the detection limit, and effectively induced neutralizing activity and antibody-secreting cell responses. In comparison with formalin inactivated RSV (FI-RSV) causing severe RSV disease after challenge, FFG-VLP vaccination did not cause weight loss, airway hyper-responsiveness, IL-4 cytokines, histopathology, and infiltrates of proinflammatory cells such as eosinophils. FFG-VLP was even more effective in preventing RSV-induced pulmonary inflammation than live RSV infections. This study provides evidence that FFG-VLP can be developed into a safe and effective RSV vaccine candidate. PMID:27123586

  13. Correlation of cytotoxic activity in lungs to recovery of normal and gamma-irradiated cotton rats from respiratory syncytial virus infection

    SciTech Connect

    Sun, C.S.; Wyde, P.R.; Knight, V.

    1983-10-01

    Cotton rats (Sigmodon hispidus) that were exposed to 300, 600, or 900 rads of gamma irradiation and inoculated intranasally 2 days later with respiratory syncytial virus (RSV) exhibited prolonged virus shedding and delayed humoral and cytotoxic immune responses compared with comparably inoculated nonirradiated control rats. In nonirradiated animals and in animals exposed to 300 and 600 rads, levels of virus declined and then disappeared from the lungs during the period in which cytotoxic activity was maximal in the lungs of these animals. In contrast, in the group of cotton rats exposed to 900 rads of irradiation, local cytotoxic activity remained low throughout the 11-day observation period, and virus was not eliminated from the lungs. Although virus-neutralizing antibodies in serum and lavage fluids from these animals may have been involved, correlation of antibody concentrations with virus clearance from lungs was not as evident. These data suggest that cytotoxic effector cells have a positive role in eliminating RSV from the lungs of unprimed cotton rats.

  14. In Vivo siRNA Delivery Using JC Virus-like Particles Decreases the Expression of RANKL in Rats

    PubMed Central

    Hoffmann, Daniel B; Böker, Kai O; Schneider, Stefan; Eckermann-Felkl, Ellen; Schuder, Angelina; Komrakova, Marina; Sehmisch, Stephan; Gruber, Jens

    2016-01-01

    Bone remodeling requires a precise balance between formation and resorption. This complex process involves numerous factors that orchestrate a multitude of biochemical events. Among these factors are hormones, growth factors, vitamins, cytokines, and, most notably, osteoprotegerin (OPG) and the receptor activator for nuclear factor-kappaB ligand (RANKL). Inflammatory cytokines play a major role in shifting the RANKL/OPG balance toward excessive RANKL, resulting in osteoclastogenesis, which in turn initiates bone resorption, which is frequently associated with osteoporosis. Rebalancing RANKL/OPG levels may be achieved through either upregulation of OPG or through transient silencing of RANKL by means of RNA interference. Here, we describe the utilization of a viral capsid-based delivery system for in vivo and in vitro RNAi using synthetic small interfering RNA (siRNA) molecules in rat osteoblasts. Polyoma JC virus-derived virus-like particles are capable of delivering siRNAs to target RANKL in osteoblast cells both in vitro and in a rat in vivo system. Expression levels were monitored using quantitative real-time polymerase reaction and enzyme-linked immunosorbent assay after single and repeated injections over a 14-day period. Our data indicate that this is an efficient and safe route for in vivo delivery of gene modulatory tools to study important molecular factors in a rat osteoporosis model. PMID:27003757

  15. In Vivo siRNA Delivery Using JC Virus-like Particles Decreases the Expression of RANKL in Rats.

    PubMed

    Hoffmann, Daniel B; Böker, Kai O; Schneider, Stefan; Eckermann-Felkl, Ellen; Schuder, Angelina; Komrakova, Marina; Sehmisch, Stephan; Gruber, Jens

    2016-01-01

    Bone remodeling requires a precise balance between formation and resorption. This complex process involves numerous factors that orchestrate a multitude of biochemical events. Among these factors are hormones, growth factors, vitamins, cytokines, and, most notably, osteoprotegerin (OPG) and the receptor activator for nuclear factor-kappaB ligand (RANKL). Inflammatory cytokines play a major role in shifting the RANKL/OPG balance toward excessive RANKL, resulting in osteoclastogenesis, which in turn initiates bone resorption, which is frequently associated with osteoporosis. Rebalancing RANKL/OPG levels may be achieved through either upregulation of OPG or through transient silencing of RANKL by means of RNA interference. Here, we describe the utilization of a viral capsid-based delivery system for in vivo and in vitro RNAi using synthetic small interfering RNA (siRNA) molecules in rat osteoblasts. Polyoma JC virus-derived virus-like particles are capable of delivering siRNAs to target RANKL in osteoblast cells both in vitro and in a rat in vivo system. Expression levels were monitored using quantitative real-time polymerase reaction and enzyme-linked immunosorbent assay after single and repeated injections over a 14-day period. Our data indicate that this is an efficient and safe route for in vivo delivery of gene modulatory tools to study important molecular factors in a rat osteoporosis model. PMID:27003757

  16. Transcriptome markers of viral persistence in naturally-infected andes virus (bunyaviridae) seropositive long-tailed pygmy rice rats.

    PubMed

    Campbell, Corey L; Torres-Perez, Fernando; Acuna-Retamar, Mariana; Schountz, Tony

    2015-01-01

    Long-tailed pygmy rice rats (Oligoryzomys longicaudatus) are principal reservoir hosts of Andes virus (ANDV) (Bunyaviridae), which causes most hantavirus cardiopulmonary syndrome cases in the Americas. To develop tools for the study of the ANDV-host interactions, we used RNA-Seq to generate a de novo transcriptome assembly. Splenic RNA from five rice rats captured in Chile, three of which were ANDV-infected, was used to generate an assembly of 66,173 annotated transcripts, including noncoding RNAs. Phylogenetic analysis of selected predicted proteins showed similarities to those of the North American deer mouse (Peromyscus maniculatus), the principal reservoir of Sin Nombre virus (SNV). One of the infected rice rats had about 50-fold more viral burden than the others, suggesting acute infection, whereas the remaining two had levels consistent with persistence. Differential expression analysis revealed distinct signatures among the infected rodents. The differences could be due to 1) variations in viral load, 2) dimorphic or reproductive differences in splenic homing of immune cells, or 3) factors of unknown etiology. In the two persistently infected rice rats, suppression of the JAK-STAT pathway at Stat5b and Ccnot1, elevation of Casp1, RIG-I pathway factors Ppp1cc and Mff, and increased FC receptor-like transcripts occurred. Caspase-1 and Stat5b activation pathways have been shown to stimulate T helper follicular cell (TFH) development in other species. These data are also consistent with reports suggestive of TFH stimulation in deer mice experimentally infected with hantaviruses. In the remaining acutely infected rice rat, the apoptotic pathway marker Cox6a1 was elevated, and putative anti-viral factors Abcb1a, Fam46c, Spp1, Rxra, Rxrb, Trmp2 and Trim58 were modulated. Transcripts for preproenkephalin (Prenk) were reduced, which may be predictive of an increased T cell activation threshold. Taken together, this transcriptome dataset will permit rigorous

  17. Transcriptome Markers of Viral Persistence in Naturally-Infected Andes Virus (Bunyaviridae) Seropositive Long-Tailed Pygmy Rice Rats

    PubMed Central

    Campbell, Corey L.; Torres-Perez, Fernando; Acuna-Retamar, Mariana; Schountz, Tony

    2015-01-01

    Long-tailed pygmy rice rats (Oligoryzomys longicaudatus) are principal reservoir hosts of Andes virus (ANDV) (Bunyaviridae), which causes most hantavirus cardiopulmonary syndrome cases in the Americas. To develop tools for the study of the ANDV-host interactions, we used RNA-Seq to generate a de novo transcriptome assembly. Splenic RNA from five rice rats captured in Chile, three of which were ANDV-infected, was used to generate an assembly of 66,173 annotated transcripts, including noncoding RNAs. Phylogenetic analysis of selected predicted proteins showed similarities to those of the North American deer mouse (Peromyscus maniculatus), the principal reservoir of Sin Nombre virus (SNV). One of the infected rice rats had about 50-fold more viral burden than the others, suggesting acute infection, whereas the remaining two had levels consistent with persistence. Differential expression analysis revealed distinct signatures among the infected rodents. The differences could be due to 1) variations in viral load, 2) dimorphic or reproductive differences in splenic homing of immune cells, or 3) factors of unknown etiology. In the two persistently infected rice rats, suppression of the JAK-STAT pathway at Stat5b and Ccnot1, elevation of Casp1, RIG-I pathway factors Ppp1cc and Mff, and increased FC receptor-like transcripts occurred. Caspase-1 and Stat5b activation pathways have been shown to stimulate T helper follicular cell (TFH) development in other species. These data are also consistent with reports suggestive of TFH stimulation in deer mice experimentally infected with hantaviruses. In the remaining acutely infected rice rat, the apoptotic pathway marker Cox6a1 was elevated, and putative anti-viral factors Abcb1a, Fam46c, Spp1, Rxra, Rxrb, Trmp2 and Trim58 were modulated. Transcripts for preproenkephalin (Prenk) were reduced, which may be predictive of an increased T cell activation threshold. Taken together, this transcriptome dataset will permit rigorous

  18. Effect of sialodacryoadenitis virus exposure on acinar epithelial cells from the rat lacrimal gland.

    PubMed

    Wickham, L A; Huang, Z; Lambert, R W; Sullivan, D A

    1997-09-01

    Sialodacryoadenitis virus (SDAV), a RNA coronavirus, induces degenerative, necrotic and atrophic alterations in acinar epithelial cells of the rat lacrimal gland. To begin to explore the underlying mechanism(s) of this viral effect, we sought in the present study to: (1) determine whether SDAV invades and replicates in lacrimal gland acinar cells in vitro and (2) assess whether short-term SDAV challenge interferes with the viability or function of acinar cells in vitro. For comparison we also evaluated the relative infectivity of SDAV in acinar epithelial cells from lacrimal, submandibular and parotid glands, given that salivary tissues are known to be highly susceptible to SDAV infection in vivo. Acinar epithelial cells from lacrimal, submandibular or parotid glands were isolated from male rats, exposed briefly to SDAV or control cell antigen and then cultured for four, eight or twelve days. At experimental termination, SDAV titers in both media and sonicated cell extracts were evaluated by plaque assay titration on mouse L2 cell monolayers. To evaluate functional aspects of lacrimal gland acinar cells, SDAV-infected cells were incubated in the presence or absence of dihydrotestosterone and culture media were analyzed by RIA to measure the extent of the androgen-induced increase in secretory component (SC) production. Our results showed that: (1) SDAV invades and replicates in lacrimal gland acinar cells, Viral challenge resulted in a significant, time-dependent increase in SDAV titers, that were primarily cell-associated and greatly exceeded amounts contained in the original inoculum; (2) SDAV infection did not compromise lacrimal acinar cell viability or prevent the cellular SC response to androgens. Viral presence, though, did often attenuate the magnitude of this hormone action; and (3) SDAV infects salivary acinar cells, but the kinetics and magnitude or viral replication in lacrimal, submandibular and parotid cells showed considerable variations. These

  19. Progress Toward a Human CD4/CCR5 Transgenic Rat Model for De Novo Infection by Human Immunodeficiency Virus Type 1

    PubMed Central

    Keppler, Oliver T.; Welte, Frank J.; Ngo, Tuan A.; Chin, Peggy S.; Patton, Kathryn S.; Tsou, Chia-Lin; Abbey, Nancy W.; Sharkey, Mark E.; Grant, Robert M.; You, Yun; Scarborough, John D.; Ellmeier, Wilfried; Littman, Dan R.; Stevenson, Mario; Charo, Israel F.; Herndier, Brian G.; Speck, Roberto F.; Goldsmith, Mark A.

    2002-01-01

    The development of a permissive small animal model for the study of human immunodeficiency virus type (HIV)-1 pathogenesis and the testing of antiviral strategies has been hampered by the inability of HIV-1 to infect primary rodent cells productively. In this study, we explored transgenic rats expressing the HIV-1 receptor complex as a susceptible host. Rats transgenic for human CD4 (hCD4) and the human chemokine receptor CCR5 (hCCR5) were generated that express the transgenes in CD4+ T lymphocytes, macrophages, and microglia. In ex vivo cultures, CD4+ T lymphocytes, macrophages, and microglia from hCD4/hCCR5 transgenic rats were highly susceptible to infection by HIV-1 R5 viruses leading to expression of abundant levels of early HIV-1 gene products comparable to those found in human reference cultures. Primary rat macrophages and microglia, but not lymphocytes, from double-transgenic rats could be productively infected by various recombinant and primary R5 strains of HIV-1. Moreover, after systemic challenge with HIV-1, lymphatic organs from hCD4/hCCR5 transgenic rats contained episomal 2–long terminal repeat (LTR) circles, integrated provirus, and early viral gene products, demonstrating susceptibility to HIV-1 in vivo. Transgenic rats also displayed a low-level plasma viremia early in infection. Thus, transgenic rats expressing the appropriate human receptor complex are promising candidates for a small animal model of HIV-1 infection. PMID:11901198

  20. Seoul virus-infected rat lung endothelial cells and alveolar macrophages differ in their ability to support virus replication and induce regulatory T cell phenotypes.

    PubMed

    Li, Wei; Klein, Sabra L

    2012-11-01

    Hantaviruses cause a persistent infection in reservoir hosts that is attributed to the upregulation of regulatory responses and downregulation of proinflammatory responses. To determine whether rat alveolar macrophages (AMs) and lung microvascular endothelial cells (LMVECs) support Seoul virus (SEOV) replication and contribute to the induction of an environment that polarizes CD4(+) T cell differentiation toward a regulatory T (Treg) cell phenotype, cultured primary rat AMs and LMVECs were mock infected or infected with SEOV and analyzed for viral replication, cytokine and chemokine responses, and expression of cell surface markers that are related to T cell activation. Allogeneic CD4(+) T cells were cocultured with SEOV-infected or mock-infected AMs or LMVECs and analyzed for helper T cell (i.e., Treg, Th17, Th1, and Th2) marker expression and Treg cell frequency. SEOV RNA and infectious particles in culture media were detected in both cell types, but at higher levels in LMVECs than in AMs postinfection. Expression of Ifnβ, Ccl5, and Cxcl10 and surface major histocompatibility complex class II (MHC-II) and MHC-I was not altered by SEOV infection in either cell type. SEOV infection significantly increased Tgfβ mRNA in AMs and the amount of programmed cell death 1 ligand 1 (PD-L1) in LMVECs. SEOV-infected LMVECs, but not AMs, induced a significant increase in Foxp3 expression and Treg cell frequency in allogeneic CD4(+) T cells, which was virus replication and cell contact dependent. These data suggest that in addition to supporting viral replication, AMs and LMVECs play distinct roles in hantavirus persistence by creating a regulatory environment through increased Tgfβ, PD-L1, and Treg cell activity.

  1. Generation and characterization of a rat monoclonal antibody against the RNA polymerase protein from Dengue Virus-2.

    PubMed

    García-Cordero, J; Carrillo-Halfon, S; León-Juárez, M; Romero-Ramírez, H; Valenzuela-León, P; López-González, M; Santos-Argumedo, L; Gutiérrez-Castañeda, B; González-Y-Merchand, J A; Cedillo-Barrón, L

    2014-01-01

    Dengue virus (DENV) RNA replication requires 2 viral proteins, non-structural protein 3 (NS3) and NS5. NS5 consists of 2 functional domains: a methyltransferase (MTase) domain involved in RNA cap formation and located in the amino terminal region and a RNA-dependent RNA polymerase domain essential for virus replication and located in the carboxyl terminal region. To gain additional insight into the structural interactions between viral proteins and cellular factors involved in DENV RNA replication, we generated a panel of rat monoclonal antibodies (mAbs) against the NS5 MTase domain. Six rat mAbs were selected from 41 clones, of which clone 13G7 was further characterized. The specificity of this antibody for NS5 was demonstrated by western blot of DENV-infected cells, which revealed that this antibody recognizes all 4 DENV serotypes. Furthermore, Western blotting analysis suggested that this antibody recognizes a sequential epitope of the NS5 protein. Positive and specific staining with 13G7 was detected predominantly in nuclei of DENV-infected cells, similarly a pattern was observed in both in human and monkey cells. Furthermore, the NS5 staining co-localized with a Lamin A protein (Pierson index: 0.7). In summary, this monoclonal antibody could be used to identify and evaluate different cellular factors that may interact with NS5 during DENV replication. PMID:24063571

  2. Laboratory investigations of African Pouched Rats (Cricetomys gambianus) as a potential reservoir host species for Monkeypox Virus

    USGS Publications Warehouse

    Hutson, Christina L.; Nakazawa, Yoshinori J.; Self, Joshua; Olson, Victoria A.; Regnery, Russell L.; Braden, Zachary; Weiss, Sonja; Malekani, Jean; Jackson, Eddie; Tate, Mallory; Karem, Kevin L.; Rocke, Tonie E.; Osorio, Jorge E.; Damon, Inger K.; Carroll, Darin S.

    2015-01-01

    Monkeypox is a zoonotic disease endemic to central and western Africa, where it is a major public health concern. Although Monkeypox virus (MPXV) and monkeypox disease in humans have been well characterized, little is known about its natural history, or its maintenance in animal populations of sylvatic reservoir(s). In 2003, several species of rodents imported from Ghana were involved in a monkeypox outbreak in the United States with individuals of three African rodent genera (Cricetomys, Graphiurus, Funisciurus) shown to be infected with MPXV. Here, we examine the course of MPXV infection in Cricetomys gambianus (pouched Gambian rats) and this rodent species’ competence as a host for the virus. We obtained ten Gambian rats from an introduced colony in Grassy Key, Florida and infected eight of these via scarification with a challenge dose of 4X104 plaque forming units (pfu) from either of the two primary clades of MPXV: Congo Basin (C-MPXV: n = 4) or West African (W-MPXV: n = 4); an additional 2 animals served as PBS controls. Viral shedding and the effect of infection on activity and physiological aspects of the animals were measured. MPXV challenged animals had significantly higher core body temperatures, reduced activity and increased weight loss than PBS controls. Viable virus was found in samples taken from animals in both experimental groups (C-MPXV and W-MPXV) between 3 and 27 days post infection (p.i.) (up to 1X108pfu/ml), with viral DNA found until day 56 p.i. The results from this work show that Cricetomys gambianus (and by inference, probably the closely related species, Cricetomys emini) can be infected with MPXV and shed viable virus particles; thus suggesting that these animals may be involved in the maintenance of MPXV in wildlife mammalian populations. More research is needed to elucidate the epidemiology of MPXV and the role of Gambian rats and other species.

  3. Seoul virus suppresses NF-kappaB-mediated inflammatory responses of antigen presenting cells from Norway rats.

    PubMed

    Au, Rebecca Y; Jedlicka, Anne E; Li, Wei; Pekosz, Andrew; Klein, Sabra L

    2010-04-25

    Hantavirus infection reduces antiviral defenses, increases regulatory responses, and causes persistent infection in rodent hosts. To address whether hantaviruses alter the maturation and functional activity of antigen presenting cells (APCs), rat bone marrow-derived dendritic cells (BMDCs) and macrophages (BMDMs) were generated and infected with Seoul virus (SEOV) or stimulated with TLR ligands. SEOV infected both DCs and macrophages, but copies of viral RNA, viral antigen, and infectious virus titers were higher in macrophages. The expression of MHCII and CD80, production of IL-6, IL-10, and TNF-alpha, and expression of Ifnbeta were attenuated in SEOV-infected APCs. Stimulation of APCs with poly I:C prior to SEOV infection increased the expression of activation markers and production of inflammatory cytokines and suppressed SEOV replication. Infection of APCs with SEOV suppressed LPS-induced activation and innate immune responses. Hantaviruses reduce the innate immune response potential of APCs derived from a natural host, which may influence persistence of these zoonotic viruses in the environment.

  4. A mos oncogene-containing retrovirus, myeloproliferative sarcoma virus, transforms rat thyroid epithelial cells and irreversibly blocks their differentiation pattern.

    PubMed Central

    Fusco, A; Portella, G; Di Fiore, P P; Berlingieri, M T; Di Lauro, R; Schneider, A B; Vecchio, G

    1985-01-01

    Differentiated, cloned rat thyroid epithelial cells (424 cells) were infected with a wild-type and a temperature-sensitive strain of the myeloproliferative variant of the Moloney murine sarcoma virus. The thyroid cells were productively infected and transformed by both virus strains and displayed some of the typical properties of malignant cells, such as morphological changes, growth in soft agar, and in vivo tumorigenicity. The acquisition of the transformed phenotype by the virus-infected cells was accompanied by a loss of the typical differentiated features of the thyroid epithelium, such as thyroglobulin (TG) secretion, iodide uptake, and dependence for growth on six factors including thyrotropin, the physiological thyroid stimulator. TG mRNA could not be demonstrated in cells transformed by both viral strains, suggesting a block at the level of the TG gene transcription. While the transformed state of the cell clones infected with the temperature-sensitive strain could be reverted by shifting the cultures to the temperature nonpermissive for transformation (39 degrees C), no reversion of the differentiated functions took place after such a shift, showing that the v-mos oncogene irreversibly shuts off the differentiation of thyroid epithelial cells in vitro. These results demonstrate, for the first time, an oncogenic potential of the v-mos oncogene family towards differentiated epithelial cells in vitro. Images PMID:2993656

  5. Reduced synthesis of pp60src and expression of the transformation-related phenotype in interferon-treated Rous sarcoma virus-transformed rat cells.

    PubMed

    Lin, S L; Garber, E A; Wang, E; Caliguiri, L A; Schellekens, H; Goldberg, A R; Tamm, I

    1983-09-01

    Treatment of Rous sarcoma virus-transformed rat cells with rat interferon-alpha (specific activity, 10(6) U/mg of protein) for 24 h caused a 50% reduction in intracellular pp60src-associated protein kinase activity. Staphylococcus aureus V8 protease digestion of pp60src, derived from 32P-labeled monolayer cultures incubated with or without interferon, revealed no differences either in the phosphopeptide pattern or in the phosphoserine-phosphotyrosine ratio. However, [3H]leucine pulse-labeling experiments showed that the synthesis of pp60src was reduced by 42 to 48%, relative to the level of bulk protein synthesis, in the interferon-treated cultures. Rat interferon-alpha also reduced the growth rate of Rous sarcoma virus-transformed rat cells in a dose-dependent manner over a 72-h period. The decrease in growth rate was accompanied by increases in the thickness and number of actin fibers per cell and by a decline in intracellular tyrosine phosphorylation by pp60src. The results suggest that interferon can inhibit the expression of the transformation-related phenotype by selectively reducing the synthesis of the Rous sarcoma virus transforming gene product. However, the interferon effects on the cytoskeletal organization and proliferation of Rous sarcoma virus-transformed cells may be due at least in part to the predominance of interferon-induced phenotypic changes over those caused by pp60src. PMID:6314124

  6. Pathogenesis of Borna disease in rats: evidence that intra-axonal spread is the major route for virus dissemination and the determinant for disease incubation.

    PubMed

    Carbone, K M; Duchala, C S; Griffin, J W; Kincaid, A L; Narayan, O

    1987-11-01

    Borna disease virus is an uncharacterized agent that causes sporadic but fatal neurological disease in horses and sheep in Europe. Studies of the infection in rats have shown that the agent has a strict tropism for neural tissues, in which it persists indefinitely. Inoculated rats developed encephalitis after an incubation period of 17 to 90 days. This report shows that the incubation period is the time required for transport of the agent in dendritic-axonal processes from the site of inoculation to the hippocampus. The immune responses to the agent had no effect on replication or transport of the virus. The neural conduit to the brain was proven by intranasal inoculation of virus that resulted in rapid transport of the agent via olfactory nerves to the hippocampus and in development of disease in 20 days. Virus inoculation into the feet resulted in spread along nerve fibers from neuron to neuron. There was sequential replication in neurons of the dorsal root ganglia adjacent to the lumbar spinal cord, the gracilis nucleus in the medulla, and pyramidal cells in the cerebral cortex, followed by infection of the hippocampal neurons and onset of disease. This progression required 50 to 60 days. The exclusiveness of the neural conduit was proven by failure to cause infection after injection of the virus intravenously or into the feet of neurectomized rats.

  7. A study of motor activity and catecholamine levels in different brain regions following Japanese encephalitis virus infection in rats.

    PubMed

    Misra, Usha Kant; Kumar, Sandeep; Kalita, Jayantee; Ahmad, Ausaf; Khanna, Vinay Kumar; Khan, Mohammad Yahiya; Palit, Gautam

    2009-10-01

    Japanese encephalitis (JE) is associated with a variety of movement disorders including transient form of pakinsonian features, dystonia and miscellaneous movement disorders. The neurotransmitters have important role in movement disorders. However their role in different brain regions in relation to behavioral activities in animal model of JE is not understood. The present study was aimed to investigate the behavioral parameters, the levels of catecholamine in brain regions--thalamus, midbrain, corpus striatum and frontal cortex on 0, 10 and 20 days post inoculation (dpi) with histopathological observations. Twelve day old Wistar strain rats were inoculated intracerebrally with a dose of 3 x 10(6) pfu of JE virus. Spontaneous locomotor activity (SLA) and grip strength were monitored. The levels of catecholamine were estimated using HPLC-ECD and histopathological changes were observed using haematoxylin and eosine staining. A significant decrease in SLA and grip strength was observed in JEV infected rats as compared to controls on 10 and 20 dpi. The levels of norepinephrine, dopamine, 3,4-dihydroxyphenylacetic acid, homovanillic acid, and serotonin were significantly decreased in all the brain regions studied with respect to controls. We did not find significant recovery in catecholamine levels and locomotor activities up to 20 dpi and any significant correlation between behavioral changes and neurotransmitter levels. However histopathological studies revealed mild reduction in degree of damage on 20 dpi. The present study demonstrates the involvement of different brain regions in altered locomotor activity which may be associated with reduction in catecholamine levels in rat model of JE.

  8. Real-Time qPCR Identifies Suitable Reference Genes for Borna Disease Virus-Infected Rat Cortical Neurons

    PubMed Central

    Zhang, Lujun; Liu, Siwen; Zhang, Liang; You, Hongmin; Huang, Rongzhong; Sun, Lin; He, Peng; Chen, Shigang; Zhang, Hong; Xie, Peng

    2014-01-01

    Quantitative real-time reverse transcription polymerase chain reaction (RT-qPCR) is the most commonly-used technique to identify gene expression profiles. The selection of stably expressed reference genes is a prerequisite to properly evaluating gene expression. Here, the suitability of commonly-used reference genes in normalizing RT-qPCR assays of mRNA expression in cultured rat cortical neurons infected with Borna disease virus (BDV) was assessed. The expressions of eight commonly-used reference genes were comparatively analyzed in BDV-infected rat cortical neurons and non-infected control neurons mainly across 9 and 12 days post-infection. These reference genes were validated by RT-qPCR and separately ranked by four statistical algorithms: geNorm, NormFinder, BestKeeper and the comparative delta-Ct method. Then, the RankAggreg package was used to construct consensus rankings. ARBP was found to be the most stable internal control gene at Day 9, and ACTB at Day 12. As the assessment of the validity of the selected reference genes confirms the suitability of applying a combination of the two most stable references genes, combining the two most stable genes for normalization of RT-qPCR studies in BDV-infected rat cortical neurons is recommended at each time point. This study can contribute to improving BDV research by providing the means by which to obtain more reliable and accurate gene expression measurements. PMID:25431926

  9. Experimental infection of highly and low pathogenic avian influenza viruses to chickens, ducks, tree sparrows, jungle crows, and black rats for the evaluation of their roles in virus transmission.

    PubMed

    Hiono, Takahiro; Okamatsu, Masatoshi; Yamamoto, Naoki; Ogasawara, Kohei; Endo, Mayumi; Kuribayashi, Saya; Shichinohe, Shintaro; Motohashi, Yurie; Chu, Duc-Huy; Suzuki, Mizuho; Ichikawa, Takaya; Nishi, Tatsuya; Abe, Yuri; Matsuno, Keita; Tanaka, Kazuyuki; Tanigawa, Tsutomu; Kida, Hiroshi; Sakoda, Yoshihiro

    2016-01-01

    Highly pathogenic avian influenza viruses (HPAIVs) have spread in both poultry and wild birds. Determining transmission routes of these viruses during an outbreak is essential for the control of avian influenza. It has been widely postulated that migratory ducks play crucial roles in the widespread dissemination of HPAIVs in poultry by carrying viruses along with their migrations; however close contacts between wild migratory ducks and poultry are less likely in modern industrial poultry farming settings. Therefore, we conducted experimental infections of HPAIVs and low pathogenic avian influenza viruses (LPAIVs) to chickens, domestic ducks, tree sparrows, jungle crows, and black rats to evaluate their roles in virus transmission. The results showed that chickens, ducks, sparrows, and crows were highly susceptible to HPAIV infection. Significant titers of virus were recovered from the sparrows and crows infected with HPAIVs, which suggests that they potentially play roles of transmission of HPAIVs to poultry. In contrast, the growth of LPAIVs was limited in each of the animals tested compared with that of HPAIVs. The present results indicate that these common synanthropes play some roles in influenza virus transmission from wild birds to poultry.

  10. Experimental infection of highly and low pathogenic avian influenza viruses to chickens, ducks, tree sparrows, jungle crows, and black rats for the evaluation of their roles in virus transmission.

    PubMed

    Hiono, Takahiro; Okamatsu, Masatoshi; Yamamoto, Naoki; Ogasawara, Kohei; Endo, Mayumi; Kuribayashi, Saya; Shichinohe, Shintaro; Motohashi, Yurie; Chu, Duc-Huy; Suzuki, Mizuho; Ichikawa, Takaya; Nishi, Tatsuya; Abe, Yuri; Matsuno, Keita; Tanaka, Kazuyuki; Tanigawa, Tsutomu; Kida, Hiroshi; Sakoda, Yoshihiro

    2016-01-15

    Highly pathogenic avian influenza viruses (HPAIVs) have spread in both poultry and wild birds. Determining transmission routes of these viruses during an outbreak is essential for the control of avian influenza. It has been widely postulated that migratory ducks play crucial roles in the widespread dissemination of HPAIVs in poultry by carrying viruses along with their migrations; however close contacts between wild migratory ducks and poultry are less likely in modern industrial poultry farming settings. Therefore, we conducted experimental infections of HPAIVs and low pathogenic avian influenza viruses (LPAIVs) to chickens, domestic ducks, tree sparrows, jungle crows, and black rats to evaluate their roles in virus transmission. The results showed that chickens, ducks, sparrows, and crows were highly susceptible to HPAIV infection. Significant titers of virus were recovered from the sparrows and crows infected with HPAIVs, which suggests that they potentially play roles of transmission of HPAIVs to poultry. In contrast, the growth of LPAIVs was limited in each of the animals tested compared with that of HPAIVs. The present results indicate that these common synanthropes play some roles in influenza virus transmission from wild birds to poultry. PMID:26711036

  11. Hepatitis C virus core protein cooperates with ras and transforms primary rat embryo fibroblasts to tumorigenic phenotype.

    PubMed Central

    Ray, R B; Lagging, L M; Meyer, K; Ray, R

    1996-01-01

    We have previously demonstrated that hepatitis C virus (HCV) core protein regulates cellular protooncogenes at the transcriptional level; this observation implicates core protein in the alteration of normal hepatocyte growth. In the present study, the transforming potential of the HCV core gene was investigated by using primary rat embryo fibroblast (REF) cells which were transfected with or without cooperative oncogenes. Integration of the HCV core gene resulted in expression of the viral protein in REF stable transformants. REF cells cotransfected with HCV core and H-ras genes became transformed and exhibited rapid proliferation, anchor-independent growth, and tumor formation in athymic nude mice. Results from these studies suggest that the core protein plays an important role in the regulation of HCV-infected cell growth and in the transformation to tumorigenic phenotype. These observations suggest a possible mechanism for this viral protein in the pathogenesis of hepatocellular carcinoma in HCV-infected humans. PMID:8676467

  12. Recombinant Subgroup B Human Respiratory Syncytial Virus Expressing Enhanced Green Fluorescent Protein Efficiently Replicates in Primary Human Cells and Is Virulent in Cotton Rats

    PubMed Central

    Lemon, Ken; Nguyen, D. Tien; Ludlow, Martin; Rennick, Linda J.; Yüksel, Selma; van Amerongen, Geert; McQuaid, Stephen; Rima, Bert K.; de Swart, Rik L.

    2014-01-01

    ABSTRACT Human respiratory syncytial virus (HRSV) is the most important viral cause of severe respiratory tract disease in infants. Two subgroups (A and B) have been identified, which cocirculate during, or alternate between, yearly epidemics and cause indistinguishable disease. Existing in vitro and in vivo models of HRSV focus almost exclusively on subgroup A viruses. Here, a recombinant (r) subgroup B virus (rHRSVB05) was generated based on a consensus genome sequence obtained directly from an unpassaged clinical specimen from a hospitalized infant. An additional transcription unit containing the gene encoding enhanced green fluorescent protein (EGFP) was introduced between the phosphoprotein and matrix genes (position 5) of the genome to generate rHRSVB05EGFP(5). The recombinant viruses replicated efficiently in both HEp-2 cells and in well-differentiated normal human bronchial cells grown at air-liquid interface. Intranasal infection of cotton rats (Sigmodon hispidus) resulted in high numbers of EGFP+ cells in epithelia of the nasal septum and conchae. When administered in a relatively large inoculum volume, the virus also replicated efficiently in bronchiolar epithelial cells and spread extensively in both the upper and lower respiratory tracts. Virus replication was not observed in ciliated epithelial cells of the trachea. This is the first virulent rHRSV strain with the genetic composition of a currently circulating wild-type virus. In vivo tracking of infected cells by means of EGFP fluorescence in the absence of cytopathic changes increases the sensitivity of virus detection in HRSV pathogenesis studies. IMPORTANCE Virology as a discipline has depended on monitoring cytopathic effects following virus culture in vitro. However, wild-type viruses isolated from patients often do not cause significant changes to infected cells, necessitating blind passage. This can lead to genetic and phenotypic changes and the generation of high-titer, laboratory

  13. Induction of caspase-dependent apoptosis in cultured rat oligodendrocytes by murine coronavirus is mediated during cell entry and does not require virus replication.

    PubMed

    Liu, Yin; Cai, Yingyun; Zhang, Xuming

    2003-11-01

    Murine coronavirus mouse hepatitis virus (MHV) causes demyelination of the central nervous system (CNS) in rats and mice. Apoptotic oligodendrocytes have been detected in the vicinity of the CNS demyelinating lesions in these animals. However, whether MHV can directly induce oligodendrocyte apoptosis has not been documented. Here, we established a rat oligodendrocyte culture that is morphologically and phenotypically indistinguishable from the primary rat oligodendrocytes. Using this culture, we showed that mature rat oligodendrocytes were permissive to MHV infection but did not support productive virus replication. Significantly, oligodendrocytes infected with both live and ultraviolet light-inactivated viruses underwent apoptosis to a similar extent, which was readily detectable at 24 h postinfection as revealed by apoptotic bodies and DNA fragmentation, indicating that MHV-induced apoptosis is mediated during the early stages of the virus life cycle and does not require virus replication. Prior treatment of cells with the lysosomotropic agents NH(4)Cl and chloroquine as well as the vacuolar proton pump-ATPase inhibitor bafilomycin A1, all of which block the acidification of the endosome, prevented oligodendrocytes from succumbing to apoptosis induced by MHV mutant OBLV60, which enters cells via endocytosis, indicating that fusion between the viral envelope and cell membranes triggers the apoptotic cascade. Treatment with the pan-caspase inhibitor Z-VAD-fmk blocked MHV-induced apoptosis, suggesting an involvement of the caspase-dependent pathway. Our results, thus, for the first time provide unequivocal evidence that infection of oligodendrocytes with MHV directly results in apoptosis. This finding provides an explanation for the destruction of oligodendrocytes and the damage of myelin sheath in MHV-infected CNS and suggests that oligodendrocyte apoptosis may be one of the underlying mechanisms for the pathogenesis of MHV-induced demyelinating diseases in animals.

  14. Spinal neurons involved in the control of the seminal vesicles: a transsynaptic labeling study using pseudorabies virus in rats.

    PubMed

    Sun, X Q; Xu, C; Leclerc, P; Benoît, G; Giuliano, F; Droupy, S

    2009-01-23

    The seminal vesicles are male accessory sex glands that mainly contribute the seminal fluid of the ejaculate. Previous studies have suggested that seminal vesicles are supplied by both sympathetic and parasympathetic nerves. However, this conclusion was mainly based on studies in pelvic major ganglions and direct neuroanatomical evidence of spinal neurons innervating the seminal vesicles is still lacking. In order to map the spinal nerve circuit innervating the seminal vesicles, the present study used the pseudorabies virus (PRV) retrograde tracing technique in combination with immunohistochemistry. Three groups of rats were prepared: (1) nerves intact; (2) right hypogastric nerve and bilateral pelvic nerves sectioned; (3) right pelvic and bilateral hypogastric nerves sectioned. For the intact group, 3 to 5 days after injection of PRV into the left seminal vesicle in male rats, immunohistochemistry for PRV was performed to map the control circuit. Double immunofluorescence experiments against PRV and choline acetyltransferase (ChAT) were performed to discriminate preganglionic neurons and interneurons. Double detection of PRV and galanin (GAL) was also performed to identify lumbar spinothalamic (LSt) cells. Three days after virus injection, both sympathetic and parasympathetic preganglionic neurons were retrograde-labeled. Four days after injection of PRV into the seminal vesicles, PRV-infected neurons were found in the dorsal horn, ventral horn, dorsal gray commissure (DGC), medial gray matter and intermediolateral cell column (IML) from T13 to S1. For the group with an intact hypogastric nerve, 4 days after injection of PRV into the seminal vesicles, PRV-infected neurons were mainly located in DGC and IML of spinal lumbar segments (L) 1-L2. However, in the group with an intact pelvic nerve, PRV-infected neurons were mainly located in DGC of L5-S1 spinal segments. At the L3-L4 level, most of the virus-labeled neurons around the central canal expressed

  15. Spinal neurons involved in the control of the seminal vesicles: a transsynaptic labeling study using pseudorabies virus in rats.

    PubMed

    Sun, X Q; Xu, C; Leclerc, P; Benoît, G; Giuliano, F; Droupy, S

    2009-01-23

    The seminal vesicles are male accessory sex glands that mainly contribute the seminal fluid of the ejaculate. Previous studies have suggested that seminal vesicles are supplied by both sympathetic and parasympathetic nerves. However, this conclusion was mainly based on studies in pelvic major ganglions and direct neuroanatomical evidence of spinal neurons innervating the seminal vesicles is still lacking. In order to map the spinal nerve circuit innervating the seminal vesicles, the present study used the pseudorabies virus (PRV) retrograde tracing technique in combination with immunohistochemistry. Three groups of rats were prepared: (1) nerves intact; (2) right hypogastric nerve and bilateral pelvic nerves sectioned; (3) right pelvic and bilateral hypogastric nerves sectioned. For the intact group, 3 to 5 days after injection of PRV into the left seminal vesicle in male rats, immunohistochemistry for PRV was performed to map the control circuit. Double immunofluorescence experiments against PRV and choline acetyltransferase (ChAT) were performed to discriminate preganglionic neurons and interneurons. Double detection of PRV and galanin (GAL) was also performed to identify lumbar spinothalamic (LSt) cells. Three days after virus injection, both sympathetic and parasympathetic preganglionic neurons were retrograde-labeled. Four days after injection of PRV into the seminal vesicles, PRV-infected neurons were found in the dorsal horn, ventral horn, dorsal gray commissure (DGC), medial gray matter and intermediolateral cell column (IML) from T13 to S1. For the group with an intact hypogastric nerve, 4 days after injection of PRV into the seminal vesicles, PRV-infected neurons were mainly located in DGC and IML of spinal lumbar segments (L) 1-L2. However, in the group with an intact pelvic nerve, PRV-infected neurons were mainly located in DGC of L5-S1 spinal segments. At the L3-L4 level, most of the virus-labeled neurons around the central canal expressed

  16. Axonal transport of rabies virus in the central nervous system of the rat.

    PubMed

    Gillet, J P; Derer, P; Tsiang, H

    1986-11-01

    Stereotaxic inoculation of rabies virus into specific nuclei in the central nervous system has been used for the investigation of the central neural transport mechanisms of viral information. The infection was monitored by specific fluorescence and peroxidase studies and the titration of viral infectivity in dissected brain areas. Twenty-four hours after inoculation into the striatum, cortex, or substantia nigra, infected neurons were detected only in cells from areas and nuclei which were related to the site of inoculation. The distribution of infected neurons showed that retrograde axoplasmic flow plays a determining role in the transport of rabies virus 24 hours after delivery of virus to specific target nuclei. Local destruction of neurons by kainic acid at the site of viral inoculation did not prevent the uptake and subsequent retrograde axonal transport of virus. There was an overall correlation between the major neural connections of the inoculated areas (e.g. the striatum) and the infected areas 24 hours later (e.g. the substantia nigra).

  17. Infection by mink cell focus-forming viruses confers interleukin 2 (IL-2) independence to an IL-2-dependent rat T-cell lymphoma line.

    PubMed Central

    Tsichlis, P N; Bear, S E

    1991-01-01

    The development of T-cell lymphomas in rodents infected with type C retroviruses has been linked to the generation of a class of envelope (env) recombinant viruses called mink cell focus-forming viruses (MCF viruses) in the preleukemic thymus. To determine whether infection by MCF viruses altered the growth phenotype of retrovirus-induced T-cell lymphomas, a Moloney murine leukemia virus-induced interleukin-2 (IL-2)-dependent rat T-cell lymphoma line (4437A) was infected with MCF-247, modified MCF-V33 (mMCF-V33), or NZB-xenotropic (NZB-X) virus. The effects of virus infection on the IL-2 dependence of these cells was examined by cultivating them in the absence of IL-2. After IL-2 withdrawal, the uninfected and NZB-X-infected cells went through a crisis period characterized by massive death. All the independently maintained cultures of MCF- and mMCF-V33-infected cells, on the other hand, became IL-2 independent without a crisis. All the polytropic virus-infected IL-2-independent cultures contained a population of cells that was polyclonal with regard to polytropic provirus integration. Over this polyclonal background each culture produced multiple clones of cells that were selected rapidly after IL-2 withdrawal. Furthermore, the resulting MCF- or mMCF-V33-infected IL-2-independent cells retained the expression of IL-2 receptor. These data show that MCF and mMCF-V33 viruses may alter the growth phenotype of a T-cell lymphoma line and suggest that their effect on cell growth may be due to the direct interaction of the MCF envelope glycoprotein with cellular components, perhaps the IL-2 receptor. Images PMID:2052545

  18. The gene therapy of collagen-induced arthritis in rats by intramuscular administration of the plasmid encoding TNF-binding domain of variola virus CrmB protein.

    PubMed

    Shchelkunov, S N; Taranov, O S; Tregubchak, T V; Maksyutov, R A; Silkov, A N; Nesterov, A E; Sennikov, S V

    2016-07-01

    Wistar rats with collagen-induced arthritis were intramuscularly injected with the recombinant plasmid pcDNA/sTNF-BD encoding the sequence of the TNF-binding protein domain of variola virus CrmB protein (VARV sTNF-BD) or the pcDNA3.1 vector. Quantitative analysis showed that the histopathological changes in the hind-limb joints of rats were most severe in the animals injected with pcDNA3.1 and much less severe in the group of rats injected with pcDNA/sTNF-BD, which indicates that gene therapy of rheumatoid arthritis is promising in the case of local administration of plasmids governing the synthesis of VARV immunomodulatory proteins.

  19. The gene therapy of collagen-induced arthritis in rats by intramuscular administration of the plasmid encoding TNF-binding domain of variola virus CrmB protein.

    PubMed

    Shchelkunov, S N; Taranov, O S; Tregubchak, T V; Maksyutov, R A; Silkov, A N; Nesterov, A E; Sennikov, S V

    2016-07-01

    Wistar rats with collagen-induced arthritis were intramuscularly injected with the recombinant plasmid pcDNA/sTNF-BD encoding the sequence of the TNF-binding protein domain of variola virus CrmB protein (VARV sTNF-BD) or the pcDNA3.1 vector. Quantitative analysis showed that the histopathological changes in the hind-limb joints of rats were most severe in the animals injected with pcDNA3.1 and much less severe in the group of rats injected with pcDNA/sTNF-BD, which indicates that gene therapy of rheumatoid arthritis is promising in the case of local administration of plasmids governing the synthesis of VARV immunomodulatory proteins. PMID:27599513

  20. Down-regulation of cytokeratin 14 mRNA in polyoma virus middle T-transformed rat liver epithelial cells.

    PubMed

    Royal, I; Gourdeau, H; Blouin, R; Marceau, N

    1992-09-01

    We have recently shown that rat liver nonparenchymal epithelial cells, such as T51B cells, selectively express cytokeratin (CK) 14 as a partner of CK8 in their intermediate filaments, and we proposed CK14 as a unique cell lineage marker of the liver epithelial cell population (R. Blouin, M-J. Blouin, I. Royal, A. Grenier, A. Loranger, D. R. Roop, and N. Marceau, Differentiation, submitted for publication, 1992). In the present study, T51B-261A (spontaneously transformed) and T51B-261B (aflatoxin B1-treated) clones and clones derived from T51B cells transfected with SV40 large T (LT) and polyoma virus middle T (MT) were used to investigate CK gene expression in nontransformed and transformed liver epithelial cells. T51B-261A, T51B-261B, MT-T51B, and LT/MT-T51B clones all grew in calcium-deficient medium and formed colonies in soft agar, whereas LT-T51B clones did not grow at all in either one of these assays. T51B-261A and T51B-261B clones formed small, slow growing tumors when injected into newborn syngenic rats, whereas the MT-T51B and LT/MT-T51B clones produced rapidly forming, large tumors. There was no effect of cell transformation on CK expression, except in the clones expressing MT, where the CK intermediate filaments were completely lost. Analyses of [35S]methionine incorporation into the Triton-resistant cytoskeleton and of total proteins confirmed that CKs were absent. In contrast, vimentin intermediate filaments remained unaffected in all of the clones.(ABSTRACT TRUNCATED AT 250 WORDS)

  1. Infections by Leptospira interrogans, Seoul virus, and Bartonella spp. among Norway rats (Rattus norvegicus) from the urban slum environment in Brazil.

    PubMed

    Costa, Federico; Porter, Fleur Helena; Rodrigues, Gorete; Farias, Helena; de Faria, Marcus Tucunduva; Wunder, Elsio A; Osikowicz, Lynn M; Kosoy, Michael Y; Reis, Mitermayer Galvão; Ko, Albert I; Childs, James E

    2014-01-01

    Norway rats (Rattus norvegicus) are reservoir hosts for zoonotic pathogens that cause significant morbidity and mortality in humans. Studies evaluating the prevalence of zoonotic pathogens in tropical Norway rat populations are rare, and data on co-infection with multiple pathogens are nonexistent. Herein, we describe the prevalence of leptospiral carriage, Seoul virus (SEOV), and Bartonella spp. infection independently, in addition to the rates of co-infection among urban, slum-dwelling Norway rats in Salvador, Brazil, trapped during the rainy season from June to August of 2010. These data were complemented with previously unpublished Leptospira and SEOV prevalence information collected in 1998. Immunofluorescence staining of kidney impressions was used to identify Leptospira interrogans in 2010, whereas isolation was used in 1998, and western blotting was used to detect SEOV antibodies in 2010, whereas enzyme-linked immunosorbent assay (ELISA) was used in 1998: in 2010, Bartonella spp. were isolated from a subsample of rats. The most common pathogen in both years was Leptospira spp. (83%, n=142 in 1998, 63%, n=84 in 2010). SEOV was detected in 18% of individuals in both 1998 and 2010 (n=78 in 1998; n=73 in 2010), and two species of Bartonella were isolated from 5 of 26 rats (19%) tested in 2010. The prevalence of all agents increased significantly with rat mass/age. Acquisition of Leptospira spp. occurred at a younger mass/age than SEOV and Bartonella spp. infection, suggesting differences in the transmission dynamics of these pathogens. These data indicate that Norway rats in Salvador serve as reservoir hosts for all three of these zoonotic pathogens and that the high prevalence of leptospiral carriage in Salvador rats poses a high degree of risk to human health.

  2. Involvement of extraneural tissues and upregulation of inducible nitric oxide synthase after experimental infection with rabies virus in BALB/c mice and LEW/SsN rats.

    PubMed

    Liao, Pi-Hung; Hsu, Yung-Hsiang; Yang, Hui-Hua; Wang, Ming-Hseng; Chen, Li-Kuang

    2012-09-01

    Rabies virus can cause fatal encephalomyelitis, but the involvement of extraneural organs has not been well characterized. In this study, we investigated the histopathological changes and the distribution of viral antigens in extraneural organs after pathogenic rabies virus infection in mouse and rat models. In histopathological examination, classical viral encephalitis and rabies-specific Negri body were observed in the brain. In addition to the central nervous system (CNS), inflammatory responses were found in other organs, such as the heart, kidney, liver, and lung. Similarly, immunohistochemical staining and reverse transcription-polymerase chain reaction revealed the presence of rabies virus in the CNS and extraneural tissues. Moreover, macrophages, especially in the lung and heart, were involved in the infection. Transcriptional analyses of the expression of inducible nitric oxide synthase (iNOS) demonstrated that rabies virus potentiated the gene expression of iNOS in the brain, lung, and heart. The immunoreactive iNOS-positive macrophages were detected adjacent to the infection. These results suggest that macrophages are involved in the extraneural infection and the expression of iNOS in macrophages contributes to the formation of tissue inflammation. Our study indicates the involvement of extraneural organs following rabies virus infection, which may aggravate the progression of this deadly disease.

  3. [Comparative analysis of the susceptibility and productivity of respiratory tract target cells of mice and rats exposed to inflienza virus in vitro].

    PubMed

    Zhukov, V A; Shishkina, L N; Sergeev, A A; Malkova, E M; Riabchikova, E I; Petrishchenko, V A; Sergeev, A N; Ustiuzhanina, N V; Nesvizhskiĭ, Iu V; Vorob'ev, A A

    2008-01-01

    The levels of susceptibility to influenza virus A/Aichi/2/68 H3N2 and the virus yield were determined using primary cells of the trachea and lungs of CD-1 mice and Wistar rats, and for 3 sets of cells obtained from primary lung cells of the both species by centrifugation in the gradient of density and by sedimentation on a surface. The values of ID50 virus dose for 10(6) cells and virus yield per 1 infected cell determined for primary mice cells were 4.0+/-0.47 and 3.2+/-0.27 IgEID50 (lung cells), 3.8+/-0.17 and 3.3+/-0.20 IgEID50 (tracheal cells), and those determined for primary rat cells were 4.0+/-0.35 and 2.1+/-0.24 IgEID50 (lung cells), 3.7+/-0.27 and 2.2+/-0.46 IgEID50 (tracheal cells). The values of ID50 and yield measured for mixtures of cells obtained from primary lung cells by centrifugation in gradient of density and by sedimentation on a surface differed insignificantly (p = 0.05) from the values of the corresponding parameters measured for lung and tracheal cells for both rats and mice. The analysis of data on the variation of the concentrations of different cell types in the experimental cell mixtures shows that type 1 and 2 alveolocytes possess significantly lower (p = 0.05) susceptibility and productivity vs. ciliated cells of the both species. The investigation was conducted within the frame of the ISTC/DARPA#450p project.

  4. SiRNA Inhibits Replication of Langat Virus, a Member of the Tick-Borne Encephalitis Virus Complex in Organotypic Rat Brain Slices

    PubMed Central

    Maffioli, Carola; Grandgirard, Denis; Leib, Stephen L.; Engler, Olivier

    2012-01-01

    Tick-borne encephalitis virus is the causative agent of tick-borne encephalitis, a potentially fatal neurological infection. Tick-borne encephalitis virus belongs to the family of flaviviruses and is transmitted by infected ticks. Despite the availability of vaccines, approximately 2000–3000 cases of tick-borne encephalitis occur annually in Europe for which no curative therapy is available. The antiviral effects of RNA mediated interference by small interfering RNA (siRNA) was evaluated in cell culture and organotypic hippocampal cultures. Langat virus, a flavivirus highly related to Tick-borne encephalitis virus exhibits low pathogenicity for humans but retains neurovirulence for rodents. Langat virus was used for the establishment of an in vitro model of tick-borne encephalitis. We analyzed the efficacy of 19 siRNA sequences targeting different regions of the Langat genome to inhibit virus replication in the two in vitro systems. The most efficient suppression of virus replication was achieved by siRNA sequences targeting structural genes and the 3′ untranslated region. When siRNA was administered to HeLa cells before the infection with Langat virus, a 96.5% reduction of viral RNA and more than 98% reduction of infectious virus particles was observed on day 6 post infection, while treatment after infection decreased the viral replication by more than 98%. In organotypic hippocampal cultures the replication of Langat virus was reduced by 99.7% by siRNA sequence D3. Organotypic hippocampal cultures represent a suitable in vitro model to investigate neuronal infection mechanisms and treatment strategies in a preserved three-dimensional tissue architecture. Our results demonstrate that siRNA is an efficient approach to limit Langat virus replication in vitro. PMID:22984545

  5. Development of a duplex real-time RT-PCR for the simultaneous detection and differentiation of Theiler's murine encephalomyelitis virus and rat theilovirus.

    PubMed

    Yuan, Wen; Wang, Jing; Xu, Fengjiao; Huang, Bihong; Lian, Yuexiao; Rao, Dan; Yin, Xueqin; Wu, Miaoli; Zhu, Yujun; Zhang, Yu; Huang, Ren; Guo, Pengju

    2016-10-01

    Theiler's murine encephalomyelitis virus (TMEV) and rat theilovirus (RTV), the member of the genus Cardiovirus, are widespread in laboratory mice and rats, and are potential contaminants of biological materials. Cardioviruses infection may cause serious complications in biomedical research. To improve the efficiency of routine screening for Cardioviruses infection, a duplex real-time reverse transcriptase polymerase chain reaction (RT-PCR) assay was developed for simultaneous detection and differentiation of TMEV and RTV. The duplex assay was specific for reference strains of TMEV and RTV, and no cross-reaction was found with seven other rodent viruses. The limits of detection of both TMEV and RTV were 4×10(1) copies RNA/reaction. Reproducibility was estimated using standard dilutions, with coefficients of variation <3.1%. 439 clinical samples were evaluated by both duplex real-time RT-PCR and conventional RT-PCR. For 439 clinical samples,95 samples were positive for TMEV and 72 samples were positive for RTV using duplex real-time RT-PCR approach, whereas only 77 samples were positive for TMEV and 66 samples were positive for RTV when conventional RT-PCR was applied. Mixed infections were found in 20 samples when analyzed by conventional RT-PCR whereas 30 samples were found to be mixed infection when duplex real-time RT-PCR was applied. This duplex assay provides a useful tool for routine health monitoring and screening of contaminated biological materials of these two viruses.

  6. Integration site of polyoma virus DNA in the inducible LPT line of polyoma-transformed rat cells.

    PubMed Central

    Mendelsohn, E; Baran, N; Neer, A; Manor, H

    1982-01-01

    The structure of the polyoma virus (Py) integration site in the inducible LPT line of Py-transformed rat cells was determined by biochemical methods of gene mapping. LPT cell DNA was digested with various restriction enzymes. The digestion products were electrophoresed in agarose gels and transferred onto nitrocellulose sheets by Southern blotting. Fragments containing viral or cell DNA sequences, or both, were identified by hybridization with Py DNA or with a cloned flanking cell DNA probe. Cleavage of LPT DNA with enzymes that restrict the Py genome once generated linear Py DNA molecules and two fragments containing both cell and viral DNA sequences. Cleavage of LPT DNA with enzymes which do not restrict Py DNA generated series of fragments whose lengths were found to differ by increments of a whole Py genome; the smallest fragment in each series was found to be longer than the viral genome. These data indicate that LPT cultures contain Py insertions of various lengths integrated into the same chromosomal site in all the cells. The length heterogeneity of the viral insertions is due to the presence of 0, 1, 2, 3. . . Py genomes arranged in a direct tandem repeat within invariable sequences of viral DNA. Double-digestion experiments were also carried out with the above enzymes and with enzymes that cleave the Py genome at multiple sites. The data obtained in these experiments were used to construct a physical map of the integration site. This map showed that the early region of the virus remained intact even in the smallest insertion (which contains no whole duplicated genomes), whereas the late region was partially duplicated and split during integration. The smallest insertion is colinear with the Py physical map over a region including the entire Py genome and at least a part of the duplicated segment. This structure could give rise to nondefective circular viral DNA molecules by single homologous recombination events. Similar recombination events may occur at

  7. Apoptosis induced by tumor necrosis factor-alpha in rat hepatocyte cell lines expressing hepatitis B virus.

    PubMed Central

    Guilhot, S.; Miller, T.; Cornman, G.; Isom, H. C.

    1996-01-01

    Three well differentiated SV40-immortalized rat hepatocyte cell lines, CWSV1, CWSV2, and CWSV14, and Hepatitis B Virus (HBV)-producing cell lines derived from them were examined for sensitivity to tumor necrosis factor (TNF)-alpha. CWSV1, CWSV2, and CWSV14 cells were co-transfected with a DNA construct containing a dimer of the HBV genome and the neo gene and selected in G418 to generate stable cell lines. Characterization of these cell lines indicated that they contain integrated HBV DNA, contain low molecular weight HBV DNA compatible with the presence of HBV replication intermediates, express HBV transcripts, and produce HBV proteins. The viability of CWSV1, CWSV2, and CWSV2 cells was not significantly altered when they were treated with TNF-alpha at concentrations as high as 20,000 U/ml. The HBV-expressing CWSV1 cell line, SV1di36, and the HBV-expressing CWSV14 cell line, SV14di208, were also not killed when treated with TNF-alpha. However, the HBV-expressing CWSV2 cell line, SV2di366, was extensively killed when treated with TNF-alpha at concentrations ranging from 200 to 20,000 U/ml. Analysis of several different HBV-producing CWSV2 cell lines indicated that TNF-alpha killing depended upon the level of HBV expression. The TNF-alpha-induced cell killing in high HBV-producing CWSV2 cell lines was accompanied by the presence of an oligonucleosomal DNA ladder characteristic of apoptosis. Images Figure 2 Figure 3 Figure 4 Figure 6 Figure 9 Figure 10 Figure 11 PMID:8774135

  8. Prolonged waking reduces human immunodeficiency virus glycoprotein 120- or tumor necrosis factor alpha-induced apoptosis in the cerebral cortex of rats.

    PubMed

    Montes-Rodríguez, Corinne J; Alavez, Silvestre; Elder, John H; Haro, Reyes; Morán, Julio; Prospéro-García, Oscar

    2004-04-29

    The human immunodeficiency virus (HIV) induces neuronal death, presumably by apoptosis. This effect may be triggered by the glycoprotein 120 (HIVgp120) released by HIV when infecting a cell, and mediated by tumor necrosis factor alpha (TNFalpha), a pro-inflammatory cytokine. Both molecules, HIVgp120 and TNFalpha, increase sleep when administered acutely in the brain. On the other hand, sleep deprivation increases the levels of several growth factors. In this context, we challenged rats with HIVgp120 or TNFalpha simultaneously with sleep deprivation. Our results indicate that both HIVgp120 and TNFalpha increase neuronal death in the rat cerebral cortex, but not hippocampus, and that this effect is completely prevented by total deprivation of sleep. These results suggest that acute total deprivation of sleep protects against the HIVgp120 and TNFalpha deleterious effects.

  9. Pulmonary Kirsten Rat Sarcoma Virus Mutation Positive Mucinous Adenocarcinoma Arising in a Congenital Pulmonary Airway Malformation, Mixed Type 1 and 2.

    PubMed

    Singh, Gopal; Coffey, Amy; Neely, Robert; Lambert, Daniel; Sonett, Joshua; Borczuk, Alain C; Gorenstein, Lyall

    2016-10-01

    Congenital pulmonary airway malformation (CPAM) is a developmental abnormality of the lung, which results from an abnormality of branching during fetal development of the lung. We report the case of an 18 year-old woman who developed Kirsten rat sarcoma virus (KRAS) mutation positive mucinous adenocarcinoma of the lung (AC) in association with mixed CPAM type 1 and 2. This case is unique as KRAS mutation positive AC is present in a setting of both CPAM 1 and 2 in the same lesion. PMID:27645976

  10. Generating an in vitro-in vivo correlation for metabolism and liver enrichment of a hepatitis C virus drug, faldaprevir, using a rat hepatocyte model (HepatoPac).

    PubMed

    Ramsden, Diane; Tweedie, Donald J; St George, Roger; Chen, Lin-Zhi; Li, Yongmei

    2014-03-01

    Hepatocytes provide an integrated model to study drug metabolism and disposition. As a result of a loss of polarity or a significant decrease in the expression of enzymes and transporters, suspended and sandwich-cultured hepatocytes have limitations in determining hepatocellular drug concentrations. Underprediction of the extent of glucuronidation is also a concern for these hepatocyte models. Faldaprevir is a hepatitis C virus protease inhibitor in late-stage development that has demonstrated significant liver enrichment in in vivo rat models based on quantitative whole-body autoradiography (QWBA) and liver-to-plasma area under-the-curve ratio. In bile duct cannulated rats, the primary biliary metabolite was a glucuronide. Owing to ethical concerns, it is difficult to assess liver enrichment in humans, and a lack of in vitro and in vivo correlation of glucuronidation has been reported. The current study was conducted to verify whether a hepatocyte model, rat HepatoPac, could overcome some of these limitations and provide validity for follow-up studies with human HepatoPac. With rat HepatoPac, liver enrichment values averaged 34-fold and were consistent with rat QWBA (26.8-fold) and in vivo data (42-fold). In contrast, liver enrichment in suspended hepatocytes was only 2.8-fold. Furthermore, the extent of faldaprevir glucuronidation in HepatoPac studies was in agreement with in vivo results, with glucuronidation as the major pathway (96%). Suspended rat hepatocytes did not generate the glucuronide or two key hydroxylated metabolites that were observed in vivo. Overall, our studies suggest that HepatoPac is a promising in vitro model to predict in vivo liver enrichment and metabolism, especially for glucuronidation, and has demonstrated superiority over suspended hepatocytes. PMID:24366905

  11. Corticosteroids modulate Seoul virus infection, regulatory T-cell responses and matrix metalloprotease 9 expression in male, but not female, Norway rats.

    PubMed

    Easterbrook, Judith D; Klein, Sabra L

    2008-11-01

    Human hantaviral disease is mediated by excessive proinflammatory and CD8+ T-cell responses, which can be alleviated by administration of corticosteroids. In contrast with humans, male rats that are infected with their species-specific hantavirus, Seoul virus (SEOV), have reduced proinflammatory and elevated regulatory T-cell responses in tissues where virus persists. To determine the effects of glucocorticoids on SEOV persistence and immune responses during infection, male and female Norway rats received sham surgeries (sham) or were adrenalectomized (ADX0), in some of which corticosterone was replaced at low (ADX10) or high (ADX80) doses. Rats were inoculated with SEOV and serum corticosterone, SEOV RNA, gene expression and protein production were measured at different time points post-inoculation. We observed that SEOV infection suppressed corticosterone in sham males to concentrations seen in ADX0 males. Furthermore, males with low corticosterone had more SEOV RNA in the lungs than either females or males with high corticosterone concentrations during peak infection. Although high concentrations of corticosterone suppressed the expression of innate antiviral and proinflammatory mediators to a greater extent in females than in males, these immunomodulatory effects did not correlate with SEOV load. Males with low corticosterone concentrations and high viral load had elevated regulatory T-cell responses and expression of matrix metalloprotease (MMP)-9. MMP-9 is a glycogenase that disrupts cellular matrices and may facilitate extravasation of SEOV-infected cells from circulation into lung tissue. Suppression of glucocorticoids may thus contribute to more efficient dissemination of SEOV in male than in female rats.

  12. Induction of Adult T-Cell Leukemia-Like Lymphoproliferative Disease and Its Inhibition by Adoptive Immunotherapy in T-Cell-Deficient Nude Rats Inoculated with Syngeneic Human T-Cell Leukemia Virus Type 1-Immortalized Cells

    PubMed Central

    Ohashi, Takashi; Hanabuchi, Shino; Kato, Hirotomo; Koya, Yoshihiro; Takemura, Fumiyo; Hirokawa, Katsuiku; Yoshiki, Takashi; Tanaka, Yuetsu; Fujii, Masahiro; Kannagi, Mari

    1999-01-01

    Human T-cell leukemia virus type 1 (HTLV-1) has been shown to be the etiologic agent of adult T-cell leukemia (ATL), but the in vivo mechanism by which the virus causes the malignant transformation is largely unknown. In order to investigate the mechanisms of HTLV-1 leukemogenesis, we developed a rat model system in which ATL-like disease was reproducibly observed, following inoculation of various rat HTLV-1-immortalized cell lines. When previously established cell lines, F344-S1 and TARS-1, but not TART-1 or W7TM-1, were inoculated, systemic multiple tumor development was observed in adult nude (nu/nu) rats. FPM1 cells, newly established from a heterozygous (nu/+) rat syngeneic to nu/nu rats, caused transient tumors only at the injection site in adult nu/nu rats, but could progressively grow in newborn nu/nu rats and metastasize in lymph nodes. The derivative cell line (FPM1-V1AX) serially passed through newborn nu/nu rats acquired the potency to grow in adult nu/nu rats. These results indicated that only some with additional changes but not all of the in vitro HTLV-1-immortalized cell lines possessed in vivo tumorigenicity. Using the syngeneic system, we further showed the inhibition of tumor development by transferring splenic T cells from immunized rats, suggesting the involvement of T cells in the regression of tumors. This novel and reproducible nude rat model of human ATL would be useful for investigation of leukemogenesis and antitumor immune responses in HTLV-1 infection. PMID:10364355

  13. Pharmacokinetics, oral bioavailability, and metabolic disposition in rats of (-)-cis-5-fluoro-1-[2-(hydroxymethyl)-1,3-oxathiolan-5-yl] cytosine, a nucleoside analog active against human immunodeficiency virus and hepatitis B virus.

    PubMed Central

    Frick, L W; St John, L; Taylor, L C; Painter, G R; Furman, P A; Liotta, D C; Furfine, E S; Nelson, D J

    1993-01-01

    The pharmacokinetics and metabolism of the potent anti-human immunodeficiency virus and anti-hepatitis B virus compound, (-)-cis-5-fluoro-1-[2-(hydroxymethyl)-1,3-oxathiolan-5-yl] cytosine (FTC), were investigated in male CD rats. Plasma clearance of 10 mg of FTC per kg of body weight was biexponential in rats, with a half-life at alpha phase of 4.7 +/- 1.1 min (mean +/- standard deviation) and a half-life at beta phase of 44 +/- 8.8 min (n = 5). The total body clearance of FTC was 1.8 +/- 0.1 liters/h/kg, and the oral bioavailability was 90% +/- 8%. The volume of distribution at steady state (Vss) was 1.5 +/- 0.1 liters/kg. Increasing the dose to 100 mg/kg slowed clearance to 1.5 +/- 0.2 liters/kg/h, lowered the Vss to 1.2 +/- 0.2 liters/kg, and reduced the oral bioavailability to 65% +/- 15%. FTC in the brains of rats was initially less than 2% of the plasma concentration but increased to 6% by 2 h postdose. Probenecid elevated levels of FTC in plasma as well as in brains but did not alter the brain-to-plasma ratio. The urinary and fecal recoveries of unchanged FTC after a 10-mg/kg intravenous dose were 87% +/- 3% and 5% +/- 1.6%, respectively. After a 10-mg/kg oral dose, respective urinary and fecal recoveries were 70% +/- 2.5% and 25% +/- 1.6%. Two sulfoxides of FTC were observed in the urine, accounting for 0.4% +/- 0.03% and 2.7% +/- 0.2% of the intravenous dose and 0.4% +/- 0.06% and 2.5% +/- 0.3% of the oral dose. Also observed were 5-fluorocytosine, representing 0.4% +/- 0.06% of the intravenous dose and 0.4% +/- 0.07% of the oral dose, and FTC glucuronide, representing 0.7% +/- 0.2% of the oral dose and 0.4% +/- 0.2% of the intravenous dose. Neither deaminated FTC nor 5-fluorouracil was observed in the urine (less than 0.2% of dose). The high oral availability and minimal metabolism of FTC encourage its further preclinical development. PMID:8285607

  14. Recombinant low-seroprevalent adenoviral vectors Ad26 and Ad35 expressing the respiratory syncytial virus (RSV) fusion protein induce protective immunity against RSV infection in cotton rats.

    PubMed

    Widjojoatmodjo, Myra N; Bogaert, Lies; Meek, Bob; Zahn, Roland; Vellinga, Jort; Custers, Jerome; Serroyen, Jan; Radošević, Katarina; Schuitemaker, Hanneke

    2015-10-01

    RSV is an important cause of lower respiratory tract infections in children, the elderly and in those with underlying medical conditions. Although the high disease burden indicates an urgent need for a vaccine against RSV, no licensed RSV vaccine is currently available. We developed an RSV vaccine candidate based on the low-seroprevalent human adenovirus serotypes 26 and 35 (Ad26 and Ad35) encoding the RSV fusion (F) gene. Single immunization of mice with either one of these vectors induced high titers of RSV neutralizing antibodies and high levels of F specific interferon-gamma-producing T cells. A Th1-type immune response was indicated by a high IgG2a/IgG1 ratio of RSV-specific antibodies, strong induction of RSV-specific interferon-gamma and tumor necrosis factor-alpha cytokine producing CD8 Tcells, and low RSV-specific CD4 T-cell induction. Both humoral and cellular responses were increased upon a boost with RSV-F expressing heterologous adenovirus vector (Ad35 boost after Ad26 prime or vice versa). Both single immunization and prime-boost immunization of cotton rats induced high and long-lasting RSV neutralizing antibody titers and protective immunity against lung and nasal RSV A2 virus load up to at least 30 weeks after immunization. Cotton rats were also completely protected against challenge with a RSV B strain (B15/97) after heterologous prime-boost immunization. Lungs from vaccinated animals showed minimal damage or inflammatory infiltrates post-challenge, in contrast to animals vaccinated with formalin-inactivated virus. Our results suggest that recombinant human adenoviral Ad26 and Ad35 vectors encoding the RSV F gene have the potential to provide broad and durable protection against RSV in humans, and appear safe to be investigated in infants.

  15. Ultrastructural Visualization of Individual Tegument Protein Dissociation during Entry of Herpes Simplex Virus 1 into Human and Rat Dorsal Root Ganglion Neurons

    PubMed Central

    Aggarwal, Anupriya; Boadle, Ross A.; Kelly, Barbara J.; Diefenbach, Russell J.; Alam, Waafiqa; Cunningham, Anthony L.

    2012-01-01

    Herpes simplex virus 1 (HSV-1) enters neurons primarily by fusion of the viral envelope with the host cell plasma membrane, leading to the release of the capsid into the cytosol. The capsid travels via microtubule-mediated retrograde transport to the nuclear membrane, where the viral DNA is released for replication in the nucleus. In the present study, the composition and kinetics of incoming HSV-1 capsids during entry and retrograde transport in axons of human fetal and dissociated rat dorsal root ganglia (DRG) neurons were examined by wide-field deconvolution microscopy and transmission immunoelectron microscopy (TIEM). We show that HSV-1 tegument proteins, including VP16, VP22, most pUL37, and some pUL36, dissociated from the incoming virions. The inner tegument proteins, including pUL36 and some pUL37, remained associated with the capsid during virus entry and transit to the nucleus in the neuronal cell body. By TIEM, a progressive loss of tegument proteins, including VP16, VP22, most pUL37, and some pUL36, was observed, with most of the tegument dissociating at the plasma membrane of the axons and the neuronal cell body. Further dissociation occurred within the axons and the cytosol as the capsids moved to the nucleus, resulting in the release of free tegument proteins, especially VP16, VP22, pUL37, and some pUL36, into the cytosol. This study elucidates ultrastructurally the composition of HSV-1 capsids that encounter the microtubules in the core of human axons and the complement of free tegument proteins released into the cytosol during virus entry. PMID:22457528

  16. Ex vivo intracoronary gene transfer of adeno-associated virus 2 leads to superior transduction over serotypes 8 and 9 in rat heart transplants.

    PubMed

    Raissadati, Alireza; Jokinen, Janne J; Syrjälä, Simo O; Keränen, Mikko A I; Krebs, Rainer; Tuuminen, Raimo; Arnaudova, Ralica; Rouvinen, Eeva; Anisimov, Andrey; Soronen, Jarkko; Pajusola, Katri; Alitalo, Kari; Nykänen, Antti I; Lemström, Karl

    2013-11-01

    Heart transplant gene therapy requires vectors with long-lasting gene expression, high cardiotropism, and minimal pathological effects. Here, we examined transduction properties of ex vivo intracoronary delivery of adeno-associated virus (AAV) serotype 2, 8, and 9 in rat syngenic and allogenic heart transplants. Adult Dark Agouti (DA) rat hearts were intracoronarily perfused ex vivo with AAV2, AAV8, or AAV9 encoding firefly luciferase and transplanted heterotopically into the abdomen of syngenic DA or allogenic Wistar-Furth (WF) recipients. Serial in vivo bioluminescent imaging of syngraft and allograft recipients was performed for 6 months and 4 weeks, respectively. Grafts were removed for PCR-, RT-PCR, and luminometer analysis. In vivo bioluminescent imaging of recipients showed that AAV9 induced a prominent and stable luciferase activity in the abdomen, when compared with AAV2 and AAV8. However, ex vivo analyses revealed that intracoronary perfusion with AAV2 resulted in the highest heart transplant transduction levels in syngrafts and allografts. Ex vivo intracoronary delivery of AAV2 resulted in efficient transgene expression in heart transplants, whereas intracoronary AAV9 escapes into adjacent tissues. In terms of cardiac transduction, these results suggest AAV2 as a potential vector for gene therapy in preclinical heart transplants studies, and highlight the importance of delivery route in gene transfer studies.

  17. Recombinant adeno-associated virus serotype 4 mediates unique and exclusive long-term transduction of retinal pigmented epithelium in rat, dog, and nonhuman primate after subretinal delivery.

    PubMed

    Weber, Michel; Rabinowitz, Joseph; Provost, Nathalie; Conrath, Hervé; Folliot, Sébastien; Briot, Delphine; Chérel, Yan; Chenuaud, Pierre; Samulski, Jude; Moullier, Philippe; Rolling, Fabienne

    2003-06-01

    We previously described chimeric recombinant adeno-associated virus (rAAV) vectors 2/4 and 2/5 as the most efficient vectors in rat retina. We now characterize these two vectors carrying the CMV.gfp genome following subretinal injection in the Wistar rat, beagle dog, and cynomolgus macaque. Both serotypes displayed stable GFP expression for the duration of the experiment (6 months) in all three animal models. Similar to the AAV-2 serotype, AAV-2/5 transduced both RPE and photoreceptor cells, with higher level of transduction in photoreceptors, whereas rAAV-2/4 transduction was unambiguously restricted to RPE cells. This unique specificity found conserved among all three species makes AAV-2/4-derived vectors attractive for retinal diseases originating in RPE such as Leber congenital amaurosis (RPE65) or retinitis pigmentosa due to a mutated mertk gene. To provide further important preclinical data, vector shedding was monitored by PCR in various biological fluids for 2 months post-rAAV administration. Following rAAV-2/4 and -5 subretinal delivery in dogs (n = 6) and in nonhuman primates (n = 2), vector genome was found in lacrymal and nasal fluids for up to 3-4 days and in the serum for up to 15-20 days. Overall, these findings will have a practical impact on the development of future gene therapy trials of retinal diseases.

  18. Dual Transneuronal Tracing in the Rat Entorhinal-Hippocampal Circuit by Intracerebral Injection of Recombinant Rabies Virus Vectors

    PubMed Central

    Ohara, Shinya; Inoue, Ken-ichi; Yamada, Masahiro; Yamawaki, Takuma; Koganezawa, Noriko; Tsutsui, Ken-Ichiro; Witter, Menno P.; Iijima, Toshio

    2008-01-01

    Dual transneuronal tracing is a novel viral tracing methodology which employs two recombinant viruses, each expressing a different reporter protein. Peripheral injection of recombinant pseudorabies viruses has been used as a powerful method to define neurons that coordinate outputs to various peripheral targets of motor and autonomic systems. Here, we assessed the feasibility of recombinants of rabies virus (RV) vector for dual transneuronal tracing in the central nervous system. First, we examined whether two different RV-vectors can double label cells in vitro, and showed that efficient double labeling can be realized by infecting targeted cells with the two RV-vectors within a short time interval. The potential of dual transneuronal tracing was then examined in vivo in the entorhinal-hippocampal circuit, using the chain of projections from CA3 pyramidal cells to CA1 pyramidal cells and subsequently to entorhinal cortex. Six days after the injection of two RV-vectors into the left and right entorhinal cortex respectively, double-labeled neurons were observed in CA3 bilaterally. Some double-labeled neurons showed a Golgi-like labeling. Dual transneuronal tracing potentially provides a powerful and sensitive method to study issues such as the amount of convergence and divergence within and between circuits in the central nervous system. Using this sensitive technique, we established that single neurons in CA3 are connected to the entorhinal cortex bilaterally with only one synaptic relay. PMID:19169410

  19. GC–MS-Based Metabonomic Profiling Displayed Differing Effects of Borna Disease Virus Natural Strain Hu-H1 and Laboratory Strain V Infection in Rat Cortical Neurons

    PubMed Central

    Liu, Siwen; Bode, Liv; Zhang, Lujun; He, Peng; Huang, Rongzhong; Sun, Lin; Chen, Shigang; Zhang, Hong; Guo, Yujie; Zhou, Jingjing; Fu, Yuying; Zhu, Dan; Xie, Peng

    2015-01-01

    Borna disease virus (BDV) persists in the central nervous systems of a wide variety of vertebrates and causes behavioral disorders. Previous studies have revealed that metabolic perturbations are associated with BDV infection. However, the pathophysiological effects of different viral strains remain largely unknown. Rat cortical neurons infected with human strain BDV Hu-H1, laboratory BDV Strain V, and non-infected control (CON) cells were cultured in vitro. At day 12 post-infection, a gas chromatography coupled with mass spectrometry (GC–MS) metabonomic approach was used to differentiate the metabonomic profiles of 35 independent intracellular samples from Hu-H1-infected cells (n = 12), Strain V-infected cells (n = 12), and CON cells (n = 11). Partial least squares discriminant analysis (PLS-DA) was performed to demonstrate discrimination between the three groups. Further statistical testing determined which individual metabolites displayed significant differences between groups. PLS-DA demonstrated that the whole metabolic pattern enabled statistical discrimination between groups. We identified 31 differential metabolites in the Hu-H1 and CON groups (21 decreased and 10 increased in Hu-H1 relative to CON), 35 differential metabolites in the Strain V and CON groups (30 decreased and 5 increased in Strain V relative to CON), and 21 differential metabolites in the Hu-H1 and Strain V groups (8 decreased and 13 increased in Hu-H1 relative to Strain V). Comparative metabonomic profiling revealed divergent perturbations in key energy and amino acid metabolites between natural strain Hu-H1 and laboratory Strain V of BDV. The two BDV strains differentially alter metabolic pathways of rat cortical neurons in vitro. Their systematic classification provides a valuable template for improved BDV strain definition in future studies. PMID:26287181

  20. Entacapone, a catechol-O-methyltransferase inhibitor, improves the motor activity and dopamine content of basal ganglia in a rat model of Parkinson's disease induced by Japanese encephalitis virus.

    PubMed

    Hamaue, Naoya; Ogata, Akihiko; Terado, Mutsuko; Tsuchida, Shirou; Yabe, Ichiro; Sasaki, Hidenao; Hirafuji, Masahiko; Togashi, Hiroko; Aoki, Takashi

    2010-01-14

    Levodopa is the main medication used for the treatment of Parkinson's disease. However, dyskinesia and wearing-off appear after the administration of high-dose levodopa for a long period. To combat the dyskinesia and wearing-off, levodopa is used together with a dopamine (DA) receptor agonist, and the amount of levodopa is decreased. We have reported the monoamine oxidase (MAO)-B inhibitor selegiline to be effective for treating motor dysfunction in Parkinson's disease model rats. We analyzed the improvement in motor functions and catecholamine contents in various brain regions induced by a combination of the catechol-O-methyltransferase (COMT) inhibitor entacapone and a levodopa/dopadecarboxylase inhibitor (DDCI) in Japanese encephalitis virus (JEV) induced Parkinson's disease model rats. Entacapone (10 mg/kg) was administered via a single oral administration with levodopa/DDCI (10 mg/kg). The motor functions of the JEV model rats were significantly worsened, compared with those of the healthy control rats. The motor functions in the Parkinson's disease model rats were significantly recovered to the same levels as the healthy control rats by the combined administration of entacapone and levodopa/DDCI. A significant improvement in motor function was not demonstrated in the case of the administration of levodopa/DDCI alone. The striatal DA concentrations in the model rat brains were significantly increased by using levodopa/DDCI together with entacapone. Motor function was recovered by raising the striatum DA density in the model rats. Thus, COMT inhibitors are useful for decreasing the amount of levodopa administered to Parkinson's disease patients.

  1. Simian virus 40 large T antigen contains two independent activities that cooperate with a ras oncogene to transform rat embryo fibroblasts.

    PubMed Central

    Cavender, J F; Conn, A; Epler, M; Lacko, H; Tevethia, M J

    1995-01-01

    The simian virus 40 large T antigen immortalizes growing primary cells in culture. In addition, this viral oncoprotein cooperates with an activated ras protein to produce dense foci on monolayers of rat embryo fibroblasts (REF). The relationship between independent immortalization and cooperative transformation with ras has not been defined. Previously, two regions of T antigen were shown to contain immortalization activities. An N-terminal fragment consisting of amino acids 1 to 147 immortalizes rodent cells (L. Sompayrac and K. J. Danna, Virology 181:412-415, 1991). Loss-of-function analysis indicated that immortalization depended on integrity of the T-antigen segments containing amino acids 351 to 450 and 533 to 626 (T. D. Kierstead and M. J. Tevethia, J. Virol. 67:1817-1829, 1993). The experiments described here were directed toward determining whether these same T-antigen regions were sufficient for cooperation with ras. Initially, constructs that produce T antigens containing amino acids 176 to 708 (T176-708) or 1 to 147 were tested in a ras cooperation assay. Both polypeptides cooperated with ras to produce dense foci on monolayers of primary REF. These results showed that T antigen contains two separate ras cooperation activities. In order to determine the N-terminal limit of the ras cooperation activity contained within the T176-708 polypeptide, a series of constructs designed to produce fusion proteins containing T-antigen segments beginning at residues 251, 301, 337, 351, 371, 401, 451, 501, 551, 601, and 651 was generated. Each of these constructs was tested for the capacity to cooperate with ras to produce dense foci on REF monolayers. The results indicated that a polypeptide containing T-antigen amino acids 251 to 708 (T251-708) was sufficient to cooperate with ras, whereas the more extensively truncated products were not. The abilities of the N-terminally truncated T antigens to bind p53 were examined in p53-deficient cells infected with a

  2. In vivo and in vitro models of demyelinating disease: activation of the adenylate cyclase system influences JHM virus expression in explanted rat oligodendrocytes.

    PubMed Central

    Beushausen, S; Narindrasorasak, S; Sanwal, B D; Dales, S

    1987-01-01

    The specificity of JHM virus (JHMV) tropism for rat oligodendrocytes, as one of the primary host cells in the central nervous system, is maintained after explanation (S. Beushausen and S. Dales, Virology 141:89-101, 1985). The temporal correlation between onset of resistance to JHMV infection in vivo, completion of myelination, and maturation of the central nervous system can be simulated in vitro by inducers of oligodendrocyte differentiation (Beushausen and Dales, Virology, 1985). Stimulation of differentiation through the elevation of intracellular cyclic AMP (cAMP) levels suggests a possible connection between activation of the adenylate cyclase system and coronavirus expression. Chromatographic analysis of cAMP-dependent protein kinase activity in cytosol extracts prepared from astrocytes or oligodendrocytes revealed that both glial cell types were deficient in protein kinase I, indicating that expression of coronavirus in differentiated cells was not contingent upon the presence of protein kinase I. However, treatment with N6,2'-O-dibutyryladenosine-3',5'-cyclic monophosphate (dbcAMP) resulted in a severalfold enhancement of the free regulatory subunit (RI) in oligodendrocytes but not in astrocytes. The RII subunit in both neural cell types was relatively unaffected. Rapid increase in RI due to dbcAMP treatment was correlated with inhibition of JHMV expression. Other differentiation inducers, including 8-Br cAMP and forskolin which, by contrast, caused a decrease in detectable RI, also blocked JHMV expression. This apparent anomaly can be attributed to an increased turnover of RI due to destabilization of the molecule which occurs upon site-specific binding of the cyclic nucleotides. On the basis of these observations, we conclude that the state of oligodendrocyte differentiation manifested with the modulation of RI regulates JHMV expression. The differentiation process did not affect either virus adsorption or sequestration but appeared to inhibit the

  3. Seroprevalence study in forestry workers from eastern Germany using novel genotype 3- and rat hepatitis E virus-specific immunoglobulin G ELISAs.

    PubMed

    Dremsek, Paul; Wenzel, Jürgen J; Johne, Reimar; Ziller, Mario; Hofmann, Jörg; Groschup, Martin H; Werdermann, Sandra; Mohn, Ulrich; Dorn, Silvia; Motz, Manfred; Mertens, Marc; Jilg, Wolfgang; Ulrich, Rainer G

    2012-05-01

    Hepatitis E virus (HEV) is the causative agent of an acute self-limiting hepatitis in humans. In industrialized countries, autochthonous cases are linked to zoonotic transmission from domestic pigs, wild boar and red deer. The main route of human infection presumably is consumption of contaminated meat. Farmers, slaughterers and veterinarians are expected to be risk groups as they work close to potentially infected animals. In this study, we tested four Escherichia coli-expressed segments of the capsid protein (CP) of a German wild boar-derived HEV genotype 3 strain for their diagnostic value in an indirect immunoglobulin G (IgG) ELISA. In an initial validation experiment, a carboxy-terminal CP segment spanning amino acid (aa) residues 326-608 outperformed the other segments harbouring aa residues 112-608, 326-660 and 112-335. Based on this segment, an indirect ELISA for detection of anti-HEV IgG antibodies in human sera was established and validated using a commercial line immunoassay as reference assay. A total of 563 sera from forestry workers of all forestry offices of Brandenburg, eastern Germany and 301 sera of blood donors from eastern Germany were surveyed using these assays. The commercial test revealed seroprevalence rates of 11% for blood donors and 18% for forestry workers. These rates are in line with data obtained by the in-house test (12 and 21%). Hence, the in-house test performed strikingly similar to the commercial test (sensitivity 0.9318, specificity 0.9542). An initial screening of forestry worker and blood donor sera with a corresponding CP segment of the recently discovered Norway rat-associated HEV revealed several strong positive sera exclusively in the forestry worker panel. Future investigations have to prove the performance of this novel IgG ELISA in large-scale seroepidemiological studies. In addition, the observed elevated seroprevalence in a forestry worker group has to be confirmed by studies on groups of forestry workers from other

  4. Borna disease virus infection impacts microRNAs associated with nervous system development, cell differentiation, proliferation and apoptosis in the hippocampi of neonatal rats.

    PubMed

    Zhao, Mingjun; Sun, Lin; Chen, Shigang; Li, Dan; Zhang, Liang; He, Peng; Liu, Xia; Zhang, Lujun; Zhang, Hong; Yang, Deyu; Huang, Rongzhong; Xie, Peng

    2015-09-01

    MicroRNAs (miRNAs) regulate gene expression by inhibiting transcription or translation and are involved in diverse biological processes, including development, cellular differentiation and tumor generation. miRNA microarray technology is a high‑throughput global analysis tool for miRNA expression profiling. Here, the hippocampi of four borna disease virus (BDV)‑infected and four non‑infected control neonatal rats were selected for miRNA microarray and bioinformatic analysis. Reverse transcription quantitative polymerase chain reaction (RT‑qPCR) analysis was subsequently performed to validate the dysregulated miRNAs. Seven miRNAs (miR‑145*, miR‑146a*, miR‑192*, miR‑200b, miR‑223*, miR‑449a and miR‑505), showed increased expression, whereas two miRNAs (miR‑126 and miR‑374) showed decreased expression in the BDV‑infected group. By RT‑qPCR validation, five miRNAs (miR‑126, miR‑200b, miR‑374, miR‑449a and miR‑505) showed significantly decreased expression (P<0.05) in response to BDV infection. Biocarta pathway analysis predicted target genes associated with 'RNA', 'IGF1mTOR', 'EIF2', 'VEGF', 'EIF', 'NTHI', 'extrinsic', 'RB', 'IL1R' and 'IGF1' pathways. Gene Ontology analysis predicted target genes associated with 'peripheral nervous system development', 'regulation of small GTPase-mediated signal transduction', 'regulation of Ras protein signal transduction', 'aerobic respiration', 'membrane fusion', 'positive regulation of cell cycle', 'cellular respiration', 'heterocycle metabolic process', 'protein tetramerization' and 'regulation of Rho protein signal transduction' processes. Among the five dysregulated miRNAs identified by RT‑qPCR, miR‑126, miR‑200b and miR‑449a showed a strong association with nervous system development, cell differentiation, proliferation and apoptosis.

  5. APP processing induced by herpes simplex virus type 1 (HSV-1) yields several APP fragments in human and rat neuronal cells.

    PubMed

    De Chiara, Giovanna; Marcocci, Maria Elena; Civitelli, Livia; Argnani, Rafaela; Piacentini, Roberto; Ripoli, Cristian; Manservigi, Roberto; Grassi, Claudio; Garaci, Enrico; Palamara, Anna Teresa

    2010-11-15

    Lifelong latent infections of the trigeminal ganglion by the neurotropic herpes simplex virus type 1 (HSV-1) are characterized by periodic reactivation. During these episodes, newly produced virions may also reach the central nervous system (CNS), causing productive but generally asymptomatic infections. Epidemiological and experimental findings suggest that HSV-1 might contribute to the pathogenesis of Alzheimer's disease (AD). This multifactorial neurodegenerative disorder is related to an overproduction of amyloid beta (Aβ) and other neurotoxic peptides, which occurs during amyloidogenic endoproteolytic processing of the transmembrane amyloid precursor protein (APP). The aim of our study was to identify the effects of productive HSV-1 infection on APP processing in neuronal cells. We found that infection of SH-SY5Y human neuroblastoma cells and rat cortical neurons is followed by multiple cleavages of APP, which result in the intra- and/or extra-cellular accumulation of various neurotoxic species. These include: i) APP fragments (APP-Fs) of 35 and 45 kDa (APP-F35 and APP-F45) that comprise portions of Aβ; ii) N-terminal APP-Fs that are secreted; iii) intracellular C-terminal APP-Fs; and iv) Aβ(1-40) and Aβ(1-42). Western blot analysis of infected-cell lysates treated with formic acid suggests that APP-F35 may be an Aβ oligomer. The multiple cleavages of APP that occur in infected cells are produced in part by known components of the amyloidogenic APP processing pathway, i.e., host-cell β-secretase, γ-secretase, and caspase-3-like enzymes. These findings demonstrate that HSV-1 infection of neuronal cells can generate multiple APP fragments with well-documented neurotoxic potentials. It is tempting to speculate that intra- and extracellular accumulation of these species in the CNS resulting from repeated HSV-1 reactivation could, in the presence of other risk factors, play a co-factorial role in the development of AD.

  6. Damage and repair in mammalian cells after exposure to non-ionizing radiations. II. Photoreactivation and killing of rat kangaroo cells (Potorous tridactylus) and Herpes simplex virus-1 by exposure to fluorescent "white" light or sunlight.

    PubMed

    Harm, H

    1980-01-01

    Photoreactivation (PR) of ultraviolet (254 nm)-inactivated cornea cells of the potoroo (or rat kangaroo; Potorous tridacylus) has been studied at wavelengths greater than 375 nm from either fluorescent "white" light or sunlight. In both cases the PR kinetics curves pass through maxima, which most likely result from the superposition of concomitant inactivation by the photoreactivating light. The inactivating effect of light was directly demonstrated for non-UV-irradiated cells, permitting correction of the PR curves. Wavelengths greater than 475 nm, and even greater than 560 nm, which do not noticeably damage cells, still photoreactivate, though less effectively than shorter wavelengths. Light treatment of UV-inactivated Herpes simplex Virus-1 (HSV-1) after infection leads to PR effects resembling those observed for cells, while light treatment of unirradiated virus after infection likewise causes inactivation. The "fluence-reduction factor" of PR, which is greater than 3 for the virus, exceeds that for the cells, where it decreases with increasing UV fluence. In vitro tests have indicated that sunlight greater than 375 nm causes photorepairable DNA lesions which are virtually fully repaired by the same light. Thus cell inactivation resulting from these solar wavelengths must be due to non-photorepairable damage.

  7. Integration of the simian virus 40 genome into cellular DNA in temperature-sensitive (N) and temperature-insensitive (A) transformants of 3T3 rat and Chinese hamster lung cells.

    PubMed Central

    Chepelinsky, A B; Seif, R; Martin, R G

    1980-01-01

    We studied the pattern of integration of the simian virus 40 (SV40) genome into the cellular DNA of N-transformants (temperature sensitive) and A-transformants (temperature insensitive) derived from 3T3-Fisher rat and Chinese hamster lung cells. The SV40 DNA was covalently linked to the cellular DNA in both types of transformants. In the rat cells, most N-transformants contained SV40 sequences integrated at a single site; most A-transformants contained SV40 sequences integrated at two to five sites. In the Chinese hamster cells, no significant correlation between the number of integration sites and the phenotype of the transformant was found; one of three integration sites were observed for both the N- and A-transformants. Single copies and tandem repeats of SV40 sequences were observed in A- and N-transformants derived from rat cells. A-transformants arise neither by amplification of the SV40 genome nor by integration at a unique site. Images PMID:6251267

  8. Transformation phenotype of polyoma virus-transformed rat fibroblasts: plasminogen activator production is modulated by the growth state of the cells and regulated by the expression of an early viral gene function.

    PubMed Central

    Perbal, B

    1980-01-01

    The expression of two transformation parameters, namely, ability to grow in agar and plasminogen activator production, was studied in several rat fibroblasts transformed by either wild-type or thermo-sensitive (tsa and ts25) polyoma viruses. The production of plasminogen activator was found to be dependent upon the growth state of the infected cells during a period of several days after infection. The analysis of the transformed phenotype of 25 tsa transformants and of 19 ts25 transformants independently isolated under various growth conditions led to the conclusion that there is no correlation between the regulation processes involved in plasminogen activator production and ability to grow without anchorage. The results obtained also suggested that the production of plasminogen activator is under the control of a functional large T antigen. PMID:6255182

  9. Inventing Viruses.

    PubMed

    Summers, William C

    2014-11-01

    In the nineteenth century, "virus" commonly meant an agent (usually unknown) that caused disease in inoculation experiments. By the 1890s, however, some disease-causing agents were found to pass through filters that retained the common bacteria. Such an agent was called "filterable virus," the best known being the virus that caused tobacco mosaic disease. By the 1920s there were many examples of filterable viruses, but no clear understanding of their nature. However, by the 1930s, the term "filterable virus" was being abandoned in favor of simply "virus," meaning an agent other than bacteria. Visualization of viruses by the electron microscope in the late 1930s finally settled their particulate nature. This article describes the ever-changing concept of "virus" and how virologists talked about viruses. These changes reflected their invention and reinvention of the concept of a virus as it was revised in light of new knowledge, new scientific values and interests, and new hegemonic technologies.

  10. Inventing Viruses.

    PubMed

    Summers, William C

    2014-11-01

    In the nineteenth century, "virus" commonly meant an agent (usually unknown) that caused disease in inoculation experiments. By the 1890s, however, some disease-causing agents were found to pass through filters that retained the common bacteria. Such an agent was called "filterable virus," the best known being the virus that caused tobacco mosaic disease. By the 1920s there were many examples of filterable viruses, but no clear understanding of their nature. However, by the 1930s, the term "filterable virus" was being abandoned in favor of simply "virus," meaning an agent other than bacteria. Visualization of viruses by the electron microscope in the late 1930s finally settled their particulate nature. This article describes the ever-changing concept of "virus" and how virologists talked about viruses. These changes reflected their invention and reinvention of the concept of a virus as it was revised in light of new knowledge, new scientific values and interests, and new hegemonic technologies. PMID:26958713

  11. Virus-mediated shRNA knockdown of prodynorphin in the rat nucleus accumbens attenuates depression-like behavior and cocaine locomotor sensitization.

    PubMed

    Cohen, Ami; Whitfield, Timothy W; Kreifeldt, Max; Koebel, Pascale; Kieffer, Brigitte L; Contet, Candice; George, Olivier; Koob, George F

    2014-01-01

    Dynorphins, endogenous opioid peptides that arise from the precursor protein prodynorphin (Pdyn), are hypothesized to be involved in the regulation of mood states and the neuroplasticity associated with addiction. The current study tested the hypothesis that dynorphin in the nucleus accumbens (NAcc) mediates such effects. More specifically, we examined whether knockdown of Pdyn within the NAcc in rats would alter the expression of depressive-like and anxiety-like behavior, as well as cocaine locomotor sensitization. Wistar rats were injected with adeno-associated viral (AAV) vectors encoding either a Pdyn-specific short hairpin RNA (AAV-shPdyn) or a scrambled shRNA (AAV-shScr) as control. Four weeks later, rats were tested for anxiety-like behavior in the elevated plus maze test and depressive-like behavior in the forced swim test (FST). Finally, rats received one daily injection of saline or cocaine (20 mg/kg, i.p.), followed by assessment of locomotion for 4 consecutive days. Following 3 days of abstinence, the rats completed 2 additional daily cocaine/saline locomotor trials. Pdyn knockdown in the NAcc led to a significant reduction in depressive-like behavior in the FST, but had no effect on anxiety-like behavior in the elevated plus maze. Pdyn knockdown did not alter baseline locomotor behavior, the locomotor response to acute cocaine, or the initial sensitization of the locomotor response to cocaine over the first 4 cocaine treatment days. However, following 3 days abstinence the locomotor response to the cocaine challenge returned to their original levels in the AAV-shPdyn rats while remaining heightened in the AAV-shScr rats. These results suggest that dynorphin in a very specific area of the nucleus accumbens contributes to depressive-like states and may be involved in neuroadaptations in the NAcc that contribute to the development of cocaine addiction as a persistent and lasting condition.

  12. Zika Virus

    MedlinePlus

    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, ...

  13. Zika Virus

    MedlinePlus

    ... Search The CDC Cancel Submit Search The CDC Zika Virus Note: Javascript is disabled or is not supported ... Areas with Zika Countries and territories with active Zika virus transmission... Mosquito Control Prevent mosquito bites, integrated mosquito ...

  14. Chikungunya Virus

    MedlinePlus

    ... traveling to countries with chikungunya virus, use insect repellent, wear long sleeves and pants, and stay in ... Chikungunya Prevention is key! Prevent Infection. Use mosquito repellent. Chikungunya Virus Distribution Chikungunya in the U.S. What's ...

  15. Differential Susceptibility of SD and CD Rats to a Novel Rat Theilovirus

    PubMed Central

    Drake, Michael T; Riley, Lela K; Livingston, Robert S

    2008-01-01

    Antibodies to rat theilovirus (RTV) have been detected in rats for many years because of their serologic crossreactivity with strains of Theiler murine encephalomyelitis virus (TMEV) of mice. Little information exists regarding this pathogen, yet it is among the most common viruses detected in serologic surveys of rats used in research. In the study reported here, a novel isolate of RTV, designated RTV1, was cultured from the feces of infected rats. The RTV1 genome contained 8094 nucleotides and had approximately 95% identity with another rat theilovirus, NSG910, and 73% identity with TMEV strains. In addition, the genome size of RTV1 was similar to those of TMEV strains but larger than that reported for NSG910. Oral inoculation of Sprague–Dawley (SD) and CD male rats (n = 10 each group) with RTV1 revealed that SD rats were more susceptible than CD rats to RTV1 infection. At 14 d postinoculation, 100% of SD rats shed virus in the feces, and 70% were positive for RTV serum antibodies. By 56 d postinoculation 30% of SD rats continued to have detectable virus in the feces, and 90% had seroconverted. In contrast, in inoculated CD rats RTV was detected only in the feces at 14 d postinoculation, at which time 40% of CD rats were fecal positive. By 56 d postinoculation only 20% of CD rats had detectable RTV serum antibodies. Our data provide additional sequence information regarding a rat-specific Cardiovirus and indicate that SD rats are more susceptible than CD rats to RTV1 infection. PMID:19004372

  16. Production of Virus by Mammalian Cells Transformed by Rous Sarcoma and Murine Sarcoma Viruses

    PubMed Central

    Valentine, Artrice F.; Bader, John P.

    1968-01-01

    Cultured cells of mammalian tumors induced by ribonucleic acid (RNA)-containing oncogenic viruses were examined for production of virus. The cell lines were established from tumors induced in rats and hamsters with either Rous sarcoma virus (Schmidt-Ruppin or Bryan strains) or murine sarcoma virus (Moloney strain). When culture fluids from each of the cell lines were examined for transforming activity or production of progeny virus, none of the cell lines was found to be infectious. However, electron microscopic examination of the various cell lines revealed the presence of particles in the rat cells transformed by either Rous sarcoma virus or murine sarcoma virus. These particles, morphologically similar to those associated with murine leukemias, were found both in the extracellular fluid concentrates and in whole-cell preparations. In the latter, they were seen budding from the cell membranes or lying in the intercellular spaces. No viruslike particles were seen in preparations from hamster tumors. Exposure of the rat cells to 3H-uridine resulted in the appearance of labeled particles with densities in sucrose gradients typical of virus (1.16 g/ml.). RNA of high molecular weight was extracted from these particles, and double-labeling experiments showed that this RNA sedimented at the same rate as RNA extracted from Rous sarcoma virus. None of the hamster cell lines gave radioactive peaks in the virus density range, and no extractable high molecular weight RNA was found. These studies suggest that the murine sarcoma virus produces an infection analogous to certain “defective” strains of Rous sarcoma virus, in that particles produced by infected cells have a low efficiency of infection. The control of the host cell over the production and properties of the RNA-containing tumorigenic viruses is discussed. Images PMID:4316021

  17. Mengovirus Replication in Novikoff Rat Hepatoma and Mouse L Cells: Effects on Synthesis of Host-Cell Macromolecules and Virus-specific Synthesis of Ribonucleic Acid

    PubMed Central

    Plagemann, Peter G. W.

    1968-01-01

    Novikoff cells (strain N1S1-67) and L-67 cells, a nutritional mutant of the common strain of mouse L cells which grows in the same medium as N1S1-67 cells, were infected with mengovirus under identical experimental conditions. The synthesis of host-cell ribonucleic acid (RNA) by either type of cell was not affected quantitatively or qualitatively until about 2 hr after infection, when viral RNA synthesis rapidly displaced the synthesis of cellular RNA. The rate of synthesis of protein by both types of cells continued at the same rate as in uninfected cells until about 3 hr after infection, and a disintegration of polyribosomes occurred only towards the end of the replicative cycle, between 5 and 6 hr. The time courses and extent of synthesis of single-stranded and double-stranded viral RNA and of the production of virus were very similar in both types of cells, in spite of the fact that the normal rate of RNA synthesis and the growth rate of uninfected N1S1-67 cells are about three times greater than those of L-67 cells. In both cells, the commencement of viral RNA synthesis coincided with the induction of viral RNA polymerase, as measured in cell-free extracts. Viral RNA polymerase activity disappeared from infected L-67 cells during the period of production of mature virus, but there was a secondary increase in activity in both types of cells coincidental with virus-induced disintegration of the host cells. Infected L-67 cells, however, disintegrated and released progeny virus much more slowly than N1S1-67 cells. The two strains of cells also differed in that replication of the same strain of mengovirus was markedly inhibited by treating N1S1-67 cells with actinomycin D prior to infection; the same treatment did not affect replication in L-67 cells. PMID:4176992

  18. Virus Maturation

    PubMed Central

    Veesler, David; Johnson, John E.

    2013-01-01

    We examined virus maturation of selected non-enveloped and enveloped ssRNA viruses; retroviruses; bacteriophages and herpes virus. Processes associated with maturation in the RNA viruses range from subtle (noda and picornaviruses) to dramatic (tetraviruses and togaviruses). The elaborate assembly and maturation pathway of HIV is discussed in contrast to the less sophisticated but highly efficient processes associated with togaviruses. Bacteriophage assembly and maturation are discussed in general terms with specific examples chosen for emphasis. Finally the herpes viruses are compared with bacteriophages. The data support divergent evolution of noda, picorna and tetraviruses from a common ancestor and divergent evolution of alpha and flaviviruses from a common ancestor. Likewise, bacteriophages and herpes viruses almost certainly share a common ancestor in their evolution. Comparing all the viruses, we conclude that maturation is a convergent process that is required to solve conflicting requirements in biological dynamics and function. PMID:22404678

  19. Adeno-associated virus mediated SOD gene therapy protects the retinal ganglion cells from chronic intraocular pressure elevation induced injury via attenuating oxidative stress and improving mitochondrial dysfunction in a rat model

    PubMed Central

    Jiang, Wenmin; Tang, Luosheng; Zeng, Jun; Chen, Baihua

    2016-01-01

    Purpose: This study aimed to determine whether chronic intraocular pressure (IOP) elevation induces retinal oxidative stress and alters mitochondrial morphology and function of retinal ganglion cells (RGC) and to explore the effects of AAV-SOD2 gene therapy on the RGC survival and mitochondrial dysfunction. Methods: Chronic experimental glaucoma was induced unilaterally in adult male Sprague-Dawley rats by laser burns at trabecular meshwork and episcleral veins 2 times with an interval of one week. One eye of each rat was intravitreally pretreated with recombinant adeno-associated virus expressing SOD2 (AAV-SOD2) or recombinant AAV expressing GFP (AAV-GFP) 21 days before glaucoma induction. RGCs counting, morphometric analysis of retina and optic nerve, and detection of activities of retinal SOD2 and catalase, MDA, mitochondrial morphology, mitochondrial dynamin protein OPA1 and DRP-1 expressions were conducted at 4, 8, 12 and 24 weeks. Results: Severe RGC loss, degeneration of optic nerve, reduced thickness of RGC layer and nerve fiber layer, significant decrease in total SOD and catalase activities, mitochondrial dysfunction and increased MDA were observed at 4, 8, 12 and 24 weeks after glaucoma. Pretreatment with AAV-SOD2 significantly reduced MDA and attenuated the damage to RGCs through a mitochondria-related pathway. Conclusion: AAV mediated pre-treatment with SOD2 is able to attenuate oxidative stress and improve mitochondrial dysfunction of RGC and optic nerve secondary to glaucoma. Thus, SOD2 may be used to prevent the retinal RGCs from glaucoma, which provides a promising strategy for glaucoma therapy. PMID:27158370

  20. Antigen-dependent proliferation and cytokine induction in respiratory syncytial virus-infected cotton rats reflect the presence of effector-memory T cells

    SciTech Connect

    Richter, Bettina W.M.; Onuska, Jaya M.; Niewiesk, Stefan; Prince, Gregory A.; Eichelberger, Maryna C. . E-mail: MarynaE@virionsystems.com

    2005-06-20

    Respiratory syncytial virus (RSV) is a major cause of lower airway disease in infants and children. Immunity to RSV is not long lasting, resulting in re-occurring infections throughout life. Effective long-lived immunity results when central-memory T cells that proliferate vigorously and secrete IL-2 are present. In contrast, effector-memory T cells that mainly produce IFN-{gamma}, facilitate virus clearance but are not long lived. To identify the type of memory response induced after RSV-A (Long) infection, we characterized the kinetics of the antigen-specific immune response and identified the types of cytokines induced. RSV-specific lymphocytic proliferation following primary and secondary infection was similar, and in both cases responses waned within a short period of time. In addition, mRNA for IFN-{gamma} but not IL-2 was induced in RSV-specific CD4{sup +} T cells. This supports the idea that the presence of effector-memory rather than central-memory T cells contributes to the ineffectiveness of the immune response to RSV.

  1. Zika virus.

    PubMed

    2016-02-10

    Essential facts Zika virus disease is caused by a virus that is transmitted by the Aedes mosquito. While it generally causes a mild illness, there is increasing concern that it is harmful in pregnancy and can cause congenital abnormalities in infants born to women infected with the virus. There is no antiviral treatment or vaccine currently available. The best form of prevention is protection against mosquito bites.

  2. Ebola virus.

    PubMed

    Streether, L A

    1999-01-01

    Ebola virus was first identified as a filovirus in 1976, following epidemics of severe haemorrhagic fever in sub-Saharan Africa. Further outbreaks have occurred since, but, despite extensive and continued investigations, the natural reservoir for the virus remains unknown. The mortality rate is high and there is no cure for Ebola virus infection. Molecular technology is proving useful in extending our knowledge of the virus. Identification of the host reservoir, control and prevention of further outbreaks, rapid diagnosis of infection, and vaccine development remain areas of continued interest in the fight against this biosafety level-four pathogen.

  3. Virus Crystallography

    NASA Astrophysics Data System (ADS)

    Fry, Elizabeth; Logan, Derek; Stuart, David

    Crystallography provides a means of visualizing intact virus particles as well as their isolated constituent proteins and enzymes (1-3) at near-atomic resolution, and is thus an extraordinarily powerful tool in the pursuit of a fuller understanding of the functioning of these simple biological systems. We have already expanded our knowledge of virus evolution, assembly, antigenic variation, and host-cell interactions; further studies will no doubt reveal much more. Although the rewards are enormous, an intact virus structure determination is not a trivial undertaking and entails a significant scaling up in terms of time and resources through all stages of data collection and processing compared to a traditional protein crystallographic structure determination. It is the methodology required for such studies that will be the focus of this chapter. The computational requirements were satisfied in the late 1970s, and when combined with the introduction of phase improvement techniques utilizing the virus symmetry (4,5), the application of crystallography to these massive macromolecular assemblies became feasible. This led to the determination of the first virus structure (the small RNA plant virus, tomato bushy stunt virus), by Harrison and coworkers in 1978 (6). The structures of two other plant viruses followed rapidly (7,8). In the 1980s, a major focus of attention was a family of animal RNA viruses; the Picornaviridae.

  4. Live Virus Smallpox Vaccine

    MedlinePlus

    ... Index SMALLPOX FACT SHEET The Live Virus Smallpox Vaccine The vaccinia virus is the "live virus" used ... cannot cause smallpox. What is a "live virus" vaccine? A "live virus" vaccine is a vaccine that ...

  5. New parvovirus in child with unexplained diarrhea, Tunisia.

    PubMed

    Phan, Tung G; Sdiri-Loulizi, Khira; Aouni, Mahjoub; Ambert-Balay, Katia; Pothier, Pierre; Deng, Xutao; Delwart, Eric

    2014-11-01

    A divergent parvovirus genome was the only eukaryotic viral sequence detected in feces of a Tunisian child with unexplained diarrhea. Tusavirus 1 shared 44% and 39% identity with the nonstructural protein 1 and viral protein 1, respectively, of the closest genome, Kilham rat parvovirus, indicating presence of a new human viral species in the Protoparvovirus genus.

  6. New Parvovirus in Child with Unexplained Diarrhea, Tunisia

    PubMed Central

    Phan, Tung G.; Sdiri-Loulizi, Khira; Aouni, Mahjoub; Ambert-Balay, Katia; Pothier, Pierre; Deng, Xutao

    2014-01-01

    A divergent parvovirus genome was the only eukaryotic viral sequence detected in feces of a Tunisian child with unexplained diarrhea. Tusavirus 1 shared 44% and 39% identity with the nonstructural protein 1 and viral protein 1, respectively, of the closest genome, Kilham rat parvovirus, indicating presence of a new human viral species in the Protoparvovirus genus. PMID:25340816

  7. Effects of provirus integration in the Tpl-1/Ets-1 locus in Moloney murine leukemia virus-induced rat T-cell lymphomas: levels of expression, polyadenylation, transcriptional initiation, and differential splicing of the Ets-1 mRNA.

    PubMed Central

    Bellacosa, A; Datta, K; Bear, S E; Patriotis, C; Lazo, P A; Copeland, N G; Jenkins, N A; Tsichlis, P N

    1994-01-01

    The Tpl-1 locus was defined as a genomic DNA region which is targeted by provirus insertion during progression of Moloney murine leukemia virus-induced rat T-cell lymphomas. Using a panel of 156 (Mus musculus x Mus spretus) x Mus musculus interspecific backcross mice, we mapped Tpl-1 to mouse chromosome 9 at a distance of 1.2 +/- 0.9 centimorgans from the Ets-1 proto-oncogene (S.E. Bear, A. Bellacosa, P.A. Lazo, N.A. Jenkins, N.G. Copeland, C. Hanson, G. Levan, and P.N. Tsichlis, Proc. Natl. Acad. Sci. USA 86:7495-7499, 1989). In this report, we present evidence that all the known Tpl-1 provirus insertions occurred immediately 5' of the first exon of Ets-1 (exon A) and that the earlier detected distance between Tpl-1 and Ets-1 was due to the high frequency of meiotic recombination in the region between the site of provirus integration and exon III. Northern (RNA) blot analysis of polyadenylated RNA from normal adult rat tissues and Moloney murine leukemia virus-induced T-cell lymphomas and hybridization to a Tpl-1/Ets-1 probe derived from the 5' end of the gene revealed two lymphoid cell-specific RNA transcripts, of 5.5 and 2.2 kb. Sequence analysis of a near-full-length (4,991-bp) cDNA clone of the 5.5-kb RNA revealed a 441-amino-acid open reading frame encoding a protein identical to the human and mouse Ets-1 proteins with the exception of five and nine species-specific conservative amino acid differences, respectively. The steady-state level of the Tpl-1/Ets-1 RNA and of the Ets-1 protein was modestly elevated in tumors carrying a provirus in the Tpl-1 locus. The relative ratio of the two Ets-1 transcripts, which were shown to arise by differential polyadenylation, was not affected by provirus insertion. Moreover, the major site of transcriptional initiation, which was localized by primer extension 250 bp upstream of the 5' end of the Ets-1 cDNA clone, was shown to be identical in normal cells and tumors carrying a provirus in the Tpl-1 locus. Finally, the

  8. The identification and neurochemical characterization of central neurons that target parasympathetic preganglionic neurons involved in the regulation of choroidal blood flow in the rat eye using pseudorabies virus, immunolabeling and conventional pathway tracing methods

    PubMed Central

    Li, Chunyan; Fitzgerald, Malinda E. C.; Del Mar, Nobel; Cuthbertson-Coates, Sherry; LeDoux, Mark S.; Gong, Suzhen; Ryan, James P.; Reiner, Anton

    2015-01-01

    The choroidal blood vessels of the eye provide the main vascular support to the outer retina. These blood vessels are under parasympathetic vasodilatory control via input from the pterygopalatine ganglion (PPG), which in turn receives its preganglionic input from the superior salivatory nucleus (SSN) of the hindbrain. The present study characterized the central neurons projecting to the SSN neurons innervating choroidal PPG neurons, using pathway tracing and immunolabeling. In the initial set of studies, minute injections of the Bartha strain of the retrograde transneuronal tracer pseudorabies virus (PRV) were made into choroid in rats in which the superior cervical ganglia had been excised (to prevent labeling of sympathetic circuitry). Diverse neuronal populations beyond the choroidal part of ipsilateral SSN showed transneuronal labeling, which notably included the parvocellular part of the paraventricular nucleus of the hypothalamus (PVN), the periaqueductal gray, the raphe magnus (RaM), the B3 region of the pons, A5, the nucleus of the solitary tract (NTS), the rostral ventrolateral medulla (RVLM), and the intermediate reticular nucleus of the medulla. The PRV+ neurons were located in the parts of these cell groups that are responsive to systemic blood pressure signals and involved in systemic blood pressure regulation by the sympathetic nervous system. In a second set of studies using PRV labeling, conventional pathway tracing, and immunolabeling, we found that PVN neurons projecting to SSN tended to be oxytocinergic and glutamatergic, RaM neurons projecting to SSN were serotonergic, and NTS neurons projecting to SSN were glutamatergic. Our results suggest that blood pressure and volume signals that drive sympathetic constriction of the systemic vasculature may also drive parasympathetic vasodilation of the choroidal vasculature, and may thereby contribute to choroidal baroregulation during low blood pressure. PMID:26082687

  9. The identification and neurochemical characterization of central neurons that target parasympathetic preganglionic neurons involved in the regulation of choroidal blood flow in the rat eye using pseudorabies virus, immunolabeling and conventional pathway tracing methods.

    PubMed

    Li, Chunyan; Fitzgerald, Malinda E C; Del Mar, Nobel; Cuthbertson-Coates, Sherry; LeDoux, Mark S; Gong, Suzhen; Ryan, James P; Reiner, Anton

    2015-01-01

    The choroidal blood vessels of the eye provide the main vascular support to the outer retina. These blood vessels are under parasympathetic vasodilatory control via input from the pterygopalatine ganglion (PPG), which in turn receives its preganglionic input from the superior salivatory nucleus (SSN) of the hindbrain. The present study characterized the central neurons projecting to the SSN neurons innervating choroidal PPG neurons, using pathway tracing and immunolabeling. In the initial set of studies, minute injections of the Bartha strain of the retrograde transneuronal tracer pseudorabies virus (PRV) were made into choroid in rats in which the superior cervical ganglia had been excised (to prevent labeling of sympathetic circuitry). Diverse neuronal populations beyond the choroidal part of ipsilateral SSN showed transneuronal labeling, which notably included the parvocellular part of the paraventricular nucleus of the hypothalamus (PVN), the periaqueductal gray, the raphe magnus (RaM), the B3 region of the pons, A5, the nucleus of the solitary tract (NTS), the rostral ventrolateral medulla (RVLM), and the intermediate reticular nucleus of the medulla. The PRV+ neurons were located in the parts of these cell groups that are responsive to systemic blood pressure signals and involved in systemic blood pressure regulation by the sympathetic nervous system. In a second set of studies using PRV labeling, conventional pathway tracing, and immunolabeling, we found that PVN neurons projecting to SSN tended to be oxytocinergic and glutamatergic, RaM neurons projecting to SSN were serotonergic, and NTS neurons projecting to SSN were glutamatergic. Our results suggest that blood pressure and volume signals that drive sympathetic constriction of the systemic vasculature may also drive parasympathetic vasodilation of the choroidal vasculature, and may thereby contribute to choroidal baroregulation during low blood pressure.

  10. Characterization of [(3)H]-LY354740 binding to rat mGlu2 and mGlu3 receptors expressed in CHO cells using semliki forest virus vectors.

    PubMed

    Schweitzer, C; Kratzeisen, C; Adam, G; Lundstrom, K; Malherbe, P; Ohresser, S; Stadler, H; Wichmann, J; Woltering, T; Mutel, V

    2000-07-24

    The binding properties of [(3)H]-LY354740 were characterized on rat metabotropic glutamate receptors mGlu2 and mGlu3 expressed in Chinese hamster ovary (CHO) cells using Semliki Forest virus vectors. The saturation isotherm gave K(D) values of 20+/-5 and 53+/-8 nM and B(max) values of 474+/-161 and 667+/-89 fmol/mg protein for mGlu2 and mGlu3 receptors, respectively. NMDA, CaCl(2), DHPG and kainate were inactive up to 1 mM, whereas LY341495, DCG IV and ibotenate inhibited [(3)H]-LY354740 binding with similar potencies on both receptors. L-CCG I, L-AP4, L-AP5, LY354740 and 1S,3R-ACPD were 2- to 4-fold more potent inhibitors of [(3)H]-LY354740 binding to mGlu2 than mGlu3 receptors. However, MPPG and L-AP3 had a 6-fold and DTT a 28-fold preference for mGlu2 over mGlu3. ZnCl(2), at 10 mM, inhibited more than 70% of [(3)H]-LY354740 binding to mGlu2 receptors. At the same concentration it did not affect significantly [(3)H]-LY354740 binding to mGlu3 receptors. On the contrary, glutamate, quisqualate, EGLU and NAAG showed a 3-, 5-, 7- and 12-fold preference for mGlu3 over mGlu2. Finally, GTPgammaS, which partially inhibited the binding on mGlu2 receptors, was inactive to inhibit [(3)H]-LY354740 binding on mGlu3 receptors. PMID:10884552

  11. Computer viruses

    NASA Technical Reports Server (NTRS)

    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.

  12. Hendra virus.

    PubMed

    Middleton, Deborah

    2014-12-01

    Hendra virus infection of horses occurred sporadically between 1994 and 2010 as a result of spill-over from the viral reservoir in Australian mainland flying-foxes, and occasional onward transmission to people also followed from exposure to affected horses. An unprecedented number of outbreaks were recorded in 2011 leading to heightened community concern. Release of an inactivated subunit vaccine for horses against Hendra virus represents the first commercially available product that is focused on mitigating the impact of a Biosafety Level 4 pathogen. Through preventing the development of acute Hendra virus disease in horses, vaccine use is also expected to reduce the risk of transmission of infection to people.

  13. Hendra virus.

    PubMed

    Middleton, Deborah

    2014-12-01

    Hendra virus infection of horses occurred sporadically between 1994 and 2010 as a result of spill-over from the viral reservoir in Australian mainland flying-foxes, and occasional onward transmission to people also followed from exposure to affected horses. An unprecedented number of outbreaks were recorded in 2011 leading to heightened community concern. Release of an inactivated subunit vaccine for horses against Hendra virus represents the first commercially available product that is focused on mitigating the impact of a Biosafety Level 4 pathogen. Through preventing the development of acute Hendra virus disease in horses, vaccine use is also expected to reduce the risk of transmission of infection to people. PMID:25281398

  14. Zika Virus

    MedlinePlus

    ... be at risk for developing fetal complications. Blood, organ and tissue donor screening tests are also needed to assure the safety of transfusion and transplantation in areas of active mosquito-borne virus transmission. ...

  15. Chikungunya virus

    MedlinePlus

    ... first time in the Americas in the Caribbean Islands. In the Americas, local transmission of the disease ... in Florida, Puerto Rico, and the U.S. Virgin Islands. How Chikungunya can spread Mosquitoes spread the virus ...

  16. Zika Virus.

    PubMed

    Phillips, Jennan A; Neyland, Anavernyel

    2016-08-01

    Zika virus (ZIKV) infections are the latest global public health emergency. Occupational health nurses can protect society by educating workers, women of childbearing age, and others traveling in ZIKV-infected areas about prevention strategies.

  17. Dengue virus.

    PubMed

    Ross, Ted M

    2010-03-01

    Dengue is the most prevalent arthropod-borne virus affecting humans today. The virus group consists of 4 serotypes that manifest with similar symptoms. Dengue causes a spectrum of disease, ranging from a mild febrile illness to a life-threatening dengue hemorrhagic fever. Breeding sites for the mosquitoes that transmit dengue virus have proliferated, partly because of population growth and uncontrolled urbanization in tropical and subtropical countries. Successful vector control programs have also been eliminated, often because of lack of governmental funding. Dengue viruses have evolved rapidly as they have spread worldwide, and genotypes associated with increased virulence have spread across Asia and the Americas. This article describes the virology, epidemiology, clinical manifestations and outcomes, and treatments/vaccines associated with dengue infection.

  18. Zika Virus.

    PubMed

    Phillips, Jennan A; Neyland, Anavernyel

    2016-08-01

    Zika virus (ZIKV) infections are the latest global public health emergency. Occupational health nurses can protect society by educating workers, women of childbearing age, and others traveling in ZIKV-infected areas about prevention strategies. PMID:27411846

  19. Transmission of Guanarito and Pirital Viruses among Wild Rodents, Venezuela

    PubMed Central

    Milazzo, Mary L.; Cajimat, Maria N.B.; Duno, Gloria; Duno, Freddy; Utrera, Antonio

    2011-01-01

    Samples from rodents captured on a farm in Venezuela in February 1997 were tested for arenavirus, antibody against Guanarito virus (GTOV), and antibody against Pirital virus (PIRV). Thirty-one (48.4%) of 64 short-tailed cane mice (Zygodontomys brevicauda) were infected with GTOV, 1 Alston’s cotton rat (Sigmodon alstoni) was infected with GTOV, and 36 (64.3%) of 56 other Alston’s cotton rats were infected with PIRV. The results of analyses of field and laboratory data suggested that horizontal transmission is the dominant mode of GTOV transmission in Z. brevicauda mice and that vertical transmission is an important mode of PIRV transmission in S. alstoni rats. The results also suggested that bodily secretions and excretions from most GTOV-infected short-tailed cane mice and most PIRV-infected Alston’s cotton rats may transmit the viruses to humans. PMID:22172205

  20. Transmission of Avian Influenza A Viruses among Species in an Artificial Barnyard

    PubMed Central

    Achenbach, Jenna E.; Bowen, Richard A.

    2011-01-01

    Waterfowl and shorebirds harbor and shed all hemagglutinin and neuraminidase subtypes of influenza A viruses and interact in nature with a broad range of other avian and mammalian species to which they might transmit such viruses. Estimating the efficiency and importance of such cross-species transmission using epidemiological approaches is difficult. We therefore addressed this question by studying transmission of low pathogenic H5 and H7 viruses from infected ducks to other common animals in a quasi-natural laboratory environment designed to mimic a common barnyard. Mallards (Anas platyrhynchos) recently infected with H5N2 or H7N3 viruses were introduced into a room housing other mallards plus chickens, blackbirds, rats and pigeons, and transmission was assessed by monitoring virus shedding (ducks) or seroconversion (other species) over the following 4 weeks. Additional animals of each species were directly inoculated with virus to characterize the effect of a known exposure. In both barnyard experiments, virus accumulated to high titers in the shared water pool. The H5N2 virus was transmitted from infected ducks to other ducks and chickens in the room either directly or through environmental contamination, but not to rats or blackbirds. Ducks infected with the H7N2 virus transmitted directly or indirectly to all other species present. Chickens and blackbirds directly inoculated with these viruses shed significant amounts of virus and seroconverted; rats and pigeons developed antiviral antibodies, but, except for one pigeon, failed to shed virus. PMID:21483843

  1. Transmission of avian influenza A viruses among species in an artificial barnyard.

    PubMed

    Achenbach, Jenna E; Bowen, Richard A

    2011-03-31

    Waterfowl and shorebirds harbor and shed all hemagglutinin and neuraminidase subtypes of influenza A viruses and interact in nature with a broad range of other avian and mammalian species to which they might transmit such viruses. Estimating the efficiency and importance of such cross-species transmission using epidemiological approaches is difficult. We therefore addressed this question by studying transmission of low pathogenic H5 and H7 viruses from infected ducks to other common animals in a quasi-natural laboratory environment designed to mimic a common barnyard. Mallards (Anas platyrhynchos) recently infected with H5N2 or H7N3 viruses were introduced into a room housing other mallards plus chickens, blackbirds, rats and pigeons, and transmission was assessed by monitoring virus shedding (ducks) or seroconversion (other species) over the following 4 weeks. Additional animals of each species were directly inoculated with virus to characterize the effect of a known exposure. In both barnyard experiments, virus accumulated to high titers in the shared water pool. The H5N2 virus was transmitted from infected ducks to other ducks and chickens in the room either directly or through environmental contamination, but not to rats or blackbirds. Ducks infected with the H7N2 virus transmitted directly or indirectly to all other species present. Chickens and blackbirds directly inoculated with these viruses shed significant amounts of virus and seroconverted; rats and pigeons developed antiviral antibodies, but, except for one pigeon, failed to shed virus.

  2. Transmission of avian influenza A viruses among species in an artificial barnyard.

    PubMed

    Achenbach, Jenna E; Bowen, Richard A

    2011-01-01

    Waterfowl and shorebirds harbor and shed all hemagglutinin and neuraminidase subtypes of influenza A viruses and interact in nature with a broad range of other avian and mammalian species to which they might transmit such viruses. Estimating the efficiency and importance of such cross-species transmission using epidemiological approaches is difficult. We therefore addressed this question by studying transmission of low pathogenic H5 and H7 viruses from infected ducks to other common animals in a quasi-natural laboratory environment designed to mimic a common barnyard. Mallards (Anas platyrhynchos) recently infected with H5N2 or H7N3 viruses were introduced into a room housing other mallards plus chickens, blackbirds, rats and pigeons, and transmission was assessed by monitoring virus shedding (ducks) or seroconversion (other species) over the following 4 weeks. Additional animals of each species were directly inoculated with virus to characterize the effect of a known exposure. In both barnyard experiments, virus accumulated to high titers in the shared water pool. The H5N2 virus was transmitted from infected ducks to other ducks and chickens in the room either directly or through environmental contamination, but not to rats or blackbirds. Ducks infected with the H7N2 virus transmitted directly or indirectly to all other species present. Chickens and blackbirds directly inoculated with these viruses shed significant amounts of virus and seroconverted; rats and pigeons developed antiviral antibodies, but, except for one pigeon, failed to shed virus. PMID:21483843

  3. Computer Viruses. Technology Update.

    ERIC Educational Resources Information Center

    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. VP2 capsid domain of the H-1 parvovirus determines susceptibility of human cancer cells to H-1 viral infection.

    PubMed

    Cho, I-R; Kaowinn, S; Song, J; Kim, S; Koh, S S; Kang, H-Y; Ha, N-C; Lee, K H; Jun, H-S; Chung, Y-H

    2015-05-01

    Although H-1 parvovirus is used as an antitumor agent, not much is known about the relationship between its specific tropism and oncolytic activity. We hypothesize that VP2, a major capsid protein of H-1 virus, determines H-1-specific tropism. To assess this, we constructed chimeric H-1 viruses expressing Kilham rat virus (KRV) capsid proteins, in their complete or partial forms. Chimeric H-1 viruses (CH1, CH2 and CH3) containing the whole KRV VP2 domain could not induce cytolysis in HeLa, A549 and Panc-1 cells. However, the other chimeric H-1 viruses (CH4 and CH5) expressing a partial KRV VP2 domain induced cytolysis. Additionally, the significant cytopathic effect caused by CH4 and CH5 infection in HeLa cells resulted from preferential viral amplification via DNA replication, RNA transcription and protein synthesis. Modeling of VP2 capsid protein showed that two variable regions (VRs) (VR0 and VR2) of H-1 VP2 protein protrude outward, because of the insertion of extra amino-acid residues, as compared with those of KRV VP2 protein. This might explain the precedence of H-1 VP2 protein over KRV in determining oncolytic activity in human cancer cells. Taking these results together, we propose that the VP2 protein of oncolytic H-1 parvovirus determines its specific tropism in human cancer cells.

  5. Parainfluenza Viruses

    PubMed Central

    Henrickson, Kelly J.

    2003-01-01

    Human parainfluenza viruses (HPIV) were first discovered in the late 1950s. Over the last decade, considerable knowledge about their molecular structure and function has been accumulated. This has led to significant changes in both the nomenclature and taxonomic relationships of these viruses. HPIV is genetically and antigenically divided into types 1 to 4. Further major subtypes of HPIV-4 (A and B) and subgroups/genotypes of HPIV-1 and HPIV-3 have been described. HPIV-1 to HPIV-3 are major causes of lower respiratory infections in infants, young children, the immunocompromised, the chronically ill, and the elderly. Each subtype can cause somewhat unique clinical diseases in different hosts. HPIV are enveloped and of medium size (150 to 250 nm), and their RNA genome is in the negative sense. These viruses belong to the Paramyxoviridae family, one of the largest and most rapidly growing groups of viruses causing significant human and veterinary disease. HPIV are closely related to recently discovered megamyxoviruses (Hendra and Nipah viruses) and metapneumovirus. PMID:12692097

  6. Seoul virus and hantavirus disease, Shenyang, People's Republic of China.

    PubMed

    Zhang, Yong-Zhen; Dong, Xue; Li, Xin; Ma, Chao; Xiong, Hai-Ping; Yan, Guang-Jie; Gao, Na; Jiang, Dong-Mei; Li, Ming-Hui; Li, Lu-Ping; Zou, Yang; Plyusnin, Alexander

    2009-02-01

    An outbreak of hemorrhagic fever with renal syndrome (HFRS) occurred among students in Shenyang Pharmaceutical University in 2006. We conducted a study to characterize etiologic agents of the outbreaks and clarify the origin of hantaviruses causing infections in humans and laboratory animals. Immunoglobulin (Ig) M or IgG antibodies against Seoul virus (SEOV) were detected in the serum samples of all 8 patients. IgG antibodies against hantavirus were also identified in laboratory rats, which were used by these students for their scientific research. Phylogenetic analysis showed that partial small segment sequences recovered from humans, laboratory rats, and local wild rats belonged to SEOV. Hantavirus sequences recovered from humans and laboratory rats clustered within 1 of 3 lineages of SEOV circulating among local wild rats in Shenyang. These results suggest that the HFRS outbreak in Shenyang was caused by SEOV that was circulating among local wild rats and had also infected the laboratory rats.

  7. FBJ osteosarcoma virus in tissue culture. III. Isolation and characterization of non-virus-producing FBJ-transformed cells.

    PubMed Central

    Levy, J A; Kazan, P L; Reilly, C A; Finkel, M P

    1978-01-01

    Hamster and rat cell lines have been established that have been transformed by FBJ murine sarcoma virus (FBJ-MuSV) but that do not produce virus. The hamster cell line originated from an osteosarcoma that appeared in a hamster inoculated at birth with an extract of a CFNo1 mouse FBJ-osteosarcoma. The rat cell line was obtained by transferring the FBJ-MuSV genome to normal rat kidney cells in the absence of the FBJ type C virus (FBJ-MuLV), which, usually in high concentration, accompanies the FBJ-MuSV. Both transformed hamster and rat cell lines contain the FBJ-MuSV genome, which can be rescued by ecotropic and xenotropic murine type C viruses. This rescued genome produces characteristic FBJ-MuSV foci in tissue culture and, in appropriate animal hosts, induces osteosarcomas typical of those induced by FBJ-MuSV. FBJ-MuSV was isolated originally from a parosteal osteosarcoma that occurred naturally in a mouse. Since there was no previous history of passage of the agent through any other animal species, these non-virus-producing hamster and rat cells transformed by FBJ-MuSV should be very helpful in molecular studies examining the origin of spontaneous sarcoma genomes in mice. PMID:206718

  8. Hendra virus

    PubMed Central

    Middleton, Deborah

    2014-01-01

    Synopsis Hendra virus infection of horses occurred sporadically between 1994 and 2010 as a result of spill-over from the viral reservoir in Australian mainland flying-foxes, and occasional onward transmission to people also followed from exposure to affected horses. For reasons that are not well understood an unprecedented number of outbreaks were recorded in 2011, including the first recorded field infection of a dog, leading to heightened community concern. Increasingly, pressure mounted to instigate measures for control of flying-fox numbers, and equine health care workers started to leave the industry on account of risk and liability concerns. Release of an inactivated subunit vaccine for horses against Hendra virus represents the first commercially available product that is focused on mitigating the impact of a Biosafety Level 4 pathogen. Through preventing the development of acute Hendra virus disease in horses, vaccine use is also expected to reduce the risk of transmission of infection to people. This approach to emerging infectious disease management focuses on the role of horses as the proximal cause of human Hendra virus disease, and may assist in redirecting community concerns away from the flying-fox reservoirs, keystone species for the ongoing health of Australia’s native forests. PMID:25281398

  9. [Influenza virus].

    PubMed

    Juozapaitis, Mindaugas; Antoniukas, Linas

    2007-01-01

    Every year, especially during the cold season, many people catch an acute respiratory disease, namely flu. It is easy to catch this disease; therefore, it spreads very rapidly and often becomes an epidemic or a global pandemic. Airway inflammation and other body ailments, which form in a very short period, torment the patient several weeks. After that, the symptoms of the disease usually disappear as quickly as they emerged. The great epidemics of flu have rather unique characteristics; therefore, it is possible to identify descriptions of such epidemics in historic sources. Already in the 4th century bc, Hippocrates himself wrote about one of them. It is known now that flu epidemics emerge rather frequently, but there are no regular intervals between those events. The epidemics can differ in their consequences, but usually they cause an increased mortality of elderly people. The great flu epidemics of the last century took millions of human lives. In 1918-19, during "The Spanish" pandemic of flu, there were around 40-50 millions of deaths all over the world; "Pandemic of Asia" in 1957 took up to one million lives, etc. Influenza virus can cause various disorders of the respiratory system: from mild inflammations of upper airways to acute pneumonia that finally results in the patient's death. Scientist Richard E. Shope, who investigated swine flu in 1920, had a suspicion that the cause of this disease might be a virus. Already in 1933, scientists from the National Institute for Medical Research in London - Wilson Smith, Sir Christopher Andrewes, and Sir Patrick Laidlaw - for the first time isolated the virus, which caused human flu. Then scientific community started the exhaustive research of influenza virus, and the great interest in this virus and its unique features is still active even today.

  10. The Geometry of Viruses.

    ERIC Educational Resources Information Center

    Case, Christine L.

    1991-01-01

    Presented is an activity in which students make models of viruses, which allows them to visualize the shape of these microorganisms. Included are some background on viruses, the biology and geometry of viruses, directions for building viruses, a comparison of cells and viruses, and questions for students. (KR)

  11. The cotton rat (Sigmodon hispidus) as an animal model for respiratory tract infections with human pathogens.

    PubMed

    Green, M Gia; Huey, Devra; Niewiesk, Stefan

    2013-05-01

    Respiratory viral infection is a great human health concern, resulting in disease, death and economic losses. Cotton rats (Sigmodon hispidus) have been particularly useful in the study of the pathogenesis of human respiratory virus infections, including the development and testing of antiviral compounds and vaccines. In this article, the authors outline the advantages of the cotton rat compared with the mouse as a model for infection with measles virus, respiratory syncytial virus, influenza virus, human parainfluenza virus and human metapneumovirus. From the literature and their own experience, the authors summarize guidelines for handling, maintaining and breeding cotton rats. In addition, they offer technical tips for carrying out infection experiments and provide information about the large array of immunological assays and reagents available for the study of immune responses (macrophages, dendritic cells, T cells, B cells, antibodies, chemokines and cytokines) in cotton rats.

  12. Plant Virus Metagenomics: Advances in Virus Discovery.

    PubMed

    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.

  13. Zika Virus.

    PubMed

    Musso, Didier; Gubler, Duane J

    2016-07-01

    Zika virus (ZIKV) is an arthropod-borne virus (arbovirus) in the genus Flavivirus and the family Flaviviridae. ZIKV was first isolated from a nonhuman primate in 1947 and from mosquitoes in 1948 in Africa, and ZIKV infections in humans were sporadic for half a century before emerging in the Pacific and the Americas. ZIKV is usually transmitted by the bite of infected mosquitoes. The clinical presentation of Zika fever is nonspecific and can be misdiagnosed as other infectious diseases, especially those due to arboviruses such as dengue and chikungunya. ZIKV infection was associated with only mild illness prior to the large French Polynesian outbreak in 2013 and 2014, when severe neurological complications were reported, and the emergence in Brazil of a dramatic increase in severe congenital malformations (microcephaly) suspected to be associated with ZIKV. Laboratory diagnosis of Zika fever relies on virus isolation or detection of ZIKV-specific RNA. Serological diagnosis is complicated by cross-reactivity among members of the Flavivirus genus. The adaptation of ZIKV to an urban cycle involving humans and domestic mosquito vectors in tropical areas where dengue is endemic suggests that the incidence of ZIKV infections may be underestimated. There is a high potential for ZIKV emergence in urban centers in the tropics that are infested with competent mosquito vectors such as Aedes aegypti and Aedes albopictus.

  14. Zika Virus and Pregnancy

    MedlinePlus

    ... 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 ...

  15. SAMPLING VIRUSES FROM SOIL

    EPA Science Inventory

    This chapter describes in detail methods for detecting viruses of bacteria and humans in soil. Methods also are presented for the assay of these viruses. Reference sources are provided for information on viruses of plants.

  16. Hanta virus (image)

    MedlinePlus

    Hanta virus is a distant cousin of Ebola virus, but is found worldwide. The virus is spread by human contact with rodent waste. Dangerous respiratory illness develops. Effective treatment is not yet ...

  17. Ebola Virus Disease

    MedlinePlus

    ... 2014 Fact sheets Features Commentaries 2014 Multimedia Contacts Ebola virus disease Fact sheet Updated January 2016 Key ... for survivors of Ebola virus disease Symptoms of Ebola virus disease The incubation period, that is, the ...

  18. Computer Viruses: An Overview.

    ERIC Educational Resources Information Center

    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)

  19. Virus Movement Maintains Local Virus Population Diversity

    SciTech Connect

    J. Snyder; B. Wiedenheft; M. Lavin; F. Roberto; J. Spuhler; A. Ortmann; T. Douglas; M. Young

    2007-11-01

    Viruses are the largest reservoir of genetic material on the planet, yet little is known about the population dynamics of any virus within its natural environment. Over a 2-year period, we monitored the diversity of two archaeal viruses found in hot springs within Yellowstone National Park (YNP). Both temporal phylogeny and neutral biodiversity models reveal that virus diversity in these local environments is not being maintained by mutation but rather by high rates of immigration from a globally distributed metacommunity. These results indicate that geographically isolated hot springs are readily able to exchange viruses. The importance of virus movement is supported by the detection of virus particles in air samples collected over YNP hot springs and by their detection in metacommunity sequencing projects conducted in the Sargasso Sea. Rapid rates of virus movement are not expected to be unique to these archaeal viruses but rather a common feature among virus metacommunities. The finding that virus immigration rather than mutation can dominate community structure has significant implications for understanding virus circulation and the role that viruses play in ecology and evolution by providing a reservoir of mobile genetic material.

  20. Low titer lentiviral transgenesis in rodents with simian immundeficiency virus vector.

    PubMed

    Bender, Balázs; Hoffmann, Orsolya Ivett; Negre, Didier; Kvell, Krisztián; Bősze, Zsuzsanna; Hiripi, László

    2013-09-01

    Efficient production of transgenic animals using low-titer lentiviral constructs remains challenging. Here we demonstrate that microinjection of simian immundeficiency virus-derived lentiviral constructs can produce transgenic mice and rats with high efficiency even when using low-titer virus preparations.

  1. Concomitant Human Infections with 2 Cowpox Virus Strains in Related Cases, France, 2011

    PubMed Central

    Ducournau, Corinne; Ferrier-Rembert, Audrey; Ferraris, Olivier; Joffre, Aurélie; Favier, Anne-Laure; Flusin, Olivier; Van Cauteren, Dieter; Kecir, Kaci; Auburtin, Brigitte; Védy, Serge; Bessaud, Maël

    2013-01-01

    We investigated 4 related human cases of cowpox virus infection reported in France during 2011. Three patients were infected by the same strain, probably transmitted by imported pet rats, and the fourth patient was infected by another strain. The 2 strains were genetically related to viruses previously isolated from humans with cowpox infection in Europe. PMID:24274113

  2. Viruses and Virus Diseases of Rubus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rubus species are propagated vegetatively and are subject to infection by viruses during development, propagation and fruit production stages. Reports of initial detection and symptoms of more than 30 viruses, virus-like diseases and phytoplasmas affecting Rubus spp. have been reviewed more than 20 ...

  3. Crystallization of viruses and virus proteins

    NASA Astrophysics Data System (ADS)

    Sehnke, Paul C.; Harrington, Melissa; Hosur, M. V.; Li, Yunge; Usha, R.; Craig Tucker, R.; Bomu, Wu; Stauffacher, Cynthia V.; Johnson, John E.

    1988-07-01

    Methods for crystallizing six isometric plant and insect viruses are presented. Procedures developed for modifying, purifying and crystallizing coat protein subunits isolated from a virus forming asymmetric, spheroidal particles, stabilized almost exclusively by protein-RNA interactions, are also discussed. The tertiary and quaternary structures of small RNA viruses are compared.

  4. The Tobacco Mosaic Virus.

    ERIC Educational Resources Information Center

    Sulzinski, Michael A.

    1992-01-01

    Explains how the tobacco mosaic virus can be used to study virology. Presents facts about the virus, procedures to handle the virus in the laboratory, and four laboratory exercises involving the viruses' survival under inactivating conditions, dilution end point, filterability, and microscopy. (MDH)

  5. Viruses of potato.

    PubMed

    Loebenstein, Gad; Gaba, Victor

    2012-01-01

    Potatoes are an important crop in Mediterranean countries both for local consumption and for export to other countries, mainly during the winter. Many Mediterranean countries import certified seed potato in addition to their own seed production. The local seeds are mainly used for planting in the autumn and winter, while the imported seed are used for early and late spring plantings. Potato virus Y is the most important virus in Mediterranean countries, present mainly in the autumn plantings. The second important virus is Potato leafroll virus, though in recent years its importance seems to be decreasing. Potato virus X, Potato virus A, Potato virus S, Potato virus M, and the viroid, Potato spindle tuber viroid, were also recorded in several Mediterranean countries. For each virus the main strains, transmission, characterization of the virus particle, its genome organization, detection, and control methods including transgenic approaches will be discussed. PMID:22682169

  6. Understanding Ebola Virus Transmission

    PubMed Central

    Judson, Seth; Prescott, Joseph; Munster, Vincent

    2015-01-01

    An unprecedented number of Ebola virus infections among healthcare workers and patients have raised questions about our understanding of Ebola virus transmission. Here, we explore different routes of Ebola virus transmission between people, summarizing the known epidemiological and experimental data. From this data, we expose important gaps in Ebola virus research pertinent to outbreak situations. We further propose experiments and methods of data collection that will enable scientists to fill these voids in our knowledge about the transmission of Ebola virus. PMID:25654239

  7. Ludwik Gross, Sarah Stewart, and the 1950s discoveries of Gross murine leukemia virus and polyoma virus.

    PubMed

    Morgan, Gregory J

    2014-12-01

    The Polish-American scientist Ludwik Gross made two important discoveries in the early 1950s. He showed that two viruses - murine leukemia virus and parotid tumor virus - could cause cancer when they were injected into susceptible animals. At first, Gross's discoveries were greeted with skepticism: it seemed implausible that viruses could cause a disease as complex as cancer. Inspired by Gross's initial experiments, similar results were obtained by Sarah Stewart and Bernice Eddy who later renamed the parotid tumor virus SE polyoma virus after finding it could cause many different types of tumors in mice, hamsters, and rats. Eventually the "SE" was dropped and virologists adopted the name "polyoma virus." After Gross's work was published, additional viruses capable of causing solid tumors or blood-borne tumors in mice were described by Arnold Graffi, Charlotte Friend, John Moloney and others. By 1961, sufficient data had been accumulated for Gross to confidently publish an extensive monograph--Oncogenic Viruses--the first history of tumor virology, which became a standard reference work and marked the emergence of tumor virology as a distinct, legitimate field of study.

  8. Ludwik Gross, Sarah Stewart, and the 1950s discoveries of Gross murine leukemia virus and polyoma virus.

    PubMed

    Morgan, Gregory J

    2014-12-01

    The Polish-American scientist Ludwik Gross made two important discoveries in the early 1950s. He showed that two viruses - murine leukemia virus and parotid tumor virus - could cause cancer when they were injected into susceptible animals. At first, Gross's discoveries were greeted with skepticism: it seemed implausible that viruses could cause a disease as complex as cancer. Inspired by Gross's initial experiments, similar results were obtained by Sarah Stewart and Bernice Eddy who later renamed the parotid tumor virus SE polyoma virus after finding it could cause many different types of tumors in mice, hamsters, and rats. Eventually the "SE" was dropped and virologists adopted the name "polyoma virus." After Gross's work was published, additional viruses capable of causing solid tumors or blood-borne tumors in mice were described by Arnold Graffi, Charlotte Friend, John Moloney and others. By 1961, sufficient data had been accumulated for Gross to confidently publish an extensive monograph--Oncogenic Viruses--the first history of tumor virology, which became a standard reference work and marked the emergence of tumor virology as a distinct, legitimate field of study. PMID:25223721

  9. Evaluation of Measles Vaccine Virus as a Vector to Deliver Respiratory Syncytial Virus Fusion Protein or Epstein-Barr Virus Glycoprotein gp350

    PubMed Central

    Mok, Hoyin; Cheng, Xing; Xu, Qi; Zengel, James R; Parhy, Bandita; Zhao, Jackie; Wang, C. Kathy; Jin, Hong

    2012-01-01

    Live attenuated recombinant measles vaccine virus (MV) Edmonston-Zagreb (EZ) strain was evaluated as a viral vector to express the ectodomains of fusion protein of respiratory syncytial virus (RSV F) or glycoprotein 350 of Epstein-Barr virus (EBV gp350) as candidate vaccines for prophylaxis of RSV and EBV. The glycoprotein gene was inserted at the 1st or the 3rd position of the measles virus genome and the recombinant viruses were generated. Insertion of the foreign gene at the 3rd position had a minimal impact on viral replication in vitro. RSV F or EBV gp350 protein was secreted from infected cells. In cotton rats, EZ-RSV F and EZ-EBV gp350 induced MV- and insert-specific antibody responses. In addition, both vaccines also induced insert specific interferon gamma (IFN-γ) secreting T cell response. EZ-RSV F protected cotton rats from pulmonary replication of RSV A2 challenge infection. In rhesus macaques, although both EZ-RSV F and EZ-EBV gp350 induced MV specific neutralizing antibody responses, only RSV F specific antibody response was detected. Thus, the immunogenicity of the foreign antigens delivered by measles vaccine virus is dependent on the nature of the insert and the animal models used for vaccine evaluation. PMID:22383906

  10. The rabies virus glycoprotein determines the distribution of different rabies virus strains in the brain.

    PubMed

    Yan, Xiuzhen; Mohankumar, Puliyur S; Dietzschold, Bernhard; Schnell, Matthies J; Fu, Zhen F

    2002-08-01

    The contribution of rabies virus (RV) glycoprotein (G) in viral distribution in the brain was examined by immunohistochemistry following stereotaxic inoculation into the rat hippocampus. Viruses used in this study include the highly neuroinvasive challenge virus standard strains (CVS-N2C and CVS-B2C) and the nonneuroinvasive attenuated SN-10 strain, as well as SN-10-derived recombinant viruses expressing the G gene from CVS-N2C (RN2C) or CVS-B2C (RB2C). The distribution of recombinant viruses in the brain was similar to those of the parental viruses from which the G was derived. For example, while CVS-B2C- and RB2C-infected neurons were seen preferentially in the hippocampus, cortex, and hypothalamus, CVS-N2C- and RN2C-infected neurons were preferentially found in the hippocampus, cortex, and thalamus. SN-10 infected efficiently almost all the brain regions. To further study the role of the RV G in virus spreading, we examined the distribution of RV antigen in brains infected with a recombinant RV in which the SN-10 G was replaced with vesicular stomatitis virus (VSV) G (SN-10-VG) was examined. The spreading of SN-10-VG to the cortex and the thalamus was drastically reduced, but the number of infected neurons in hippocampus and hypothalamus, particularly the paraventricular nucleus, was similar to the SN-10 virus. This pattern of spreading resembles that of VSV. Together, our data demonstrate that it is the G protein that determines the distribution pattern of RV in the brain.

  11. Redistribution and modulation of Gross murine leukemia virus antigens induced by specific antibodies.

    PubMed

    Ioachim, H L; Sabbath, M

    1979-01-01

    Gross murine leukemia virus (G-MuLV)-induced rat leukemia cells in tissue culture replicate G-MuLV, express strong virus-associated membrane antigenicity, and are consistently killed by specific antibodies and complement in cytotoxicity tests. To explore the effect of specific antibodies, rat anti-G-MuLV antisera were added to the cultures of leukemia cells for variable periods of time. Redistribution of virus particles as well as of membrane virus antigens in the form of polar patches and caps was observed by electron microscopy, indirect immunofluorescence, and immunoelectron microscopy. Substantial decreases in cytotoxicity indexes accompanied these changes. The antigen modulation induced by anti-G-MuLV antibodies in vitro paralleled similar changes obtained in vivo by transplanttion of leukemia cells in rats with high anti-G-MuLV antibody titers. The importance of antigen modulation in this system resides in its direct relationship with the malignant potential of the leukemia cells.

  12. Virus-Vectored Influenza Virus Vaccines

    PubMed Central

    Tripp, Ralph A.; Tompkins, S. Mark

    2014-01-01

    Despite the availability of an inactivated vaccine that has been licensed for >50 years, the influenza virus continues to cause morbidity and mortality worldwide. Constant evolution of circulating influenza virus strains and the emergence of new strains diminishes the effectiveness of annual vaccines that rely on a match with circulating influenza strains. Thus, there is a continued need for new, efficacious vaccines conferring cross-clade protection to avoid the need for biannual reformulation of seasonal influenza vaccines. Recombinant virus-vectored vaccines are an appealing alternative to classical inactivated vaccines because virus vectors enable native expression of influenza antigens, even from virulent influenza viruses, while expressed in the context of the vector that can improve immunogenicity. In addition, a vectored vaccine often enables delivery of the vaccine to sites of inductive immunity such as the respiratory tract enabling protection from influenza virus infection. Moreover, the ability to readily manipulate virus vectors to produce novel influenza vaccines may provide the quickest path toward a universal vaccine protecting against all influenza viruses. This review will discuss experimental virus-vectored vaccines for use in humans, comparing them to licensed vaccines and the hurdles faced for licensure of these next-generation influenza virus vaccines. PMID:25105278

  13. Viruses infecting reptiles.

    PubMed

    Marschang, Rachel E

    2011-11-01

    A large number of viruses have been described in many different reptiles. These viruses include arboviruses that primarily infect mammals or birds as well as viruses that are specific for reptiles. Interest in arboviruses infecting reptiles has mainly focused on the role reptiles may play in the epidemiology of these viruses, especially over winter. Interest in reptile specific viruses has concentrated on both their importance for reptile medicine as well as virus taxonomy and evolution. The impact of many viral infections on reptile health is not known. Koch's postulates have only been fulfilled for a limited number of reptilian viruses. As diagnostic testing becomes more sensitive, multiple infections with various viruses and other infectious agents are also being detected. In most cases the interactions between these different agents are not known. This review provides an update on viruses described in reptiles, the animal species in which they have been detected, and what is known about their taxonomic positions.

  14. Viruses Infecting Reptiles

    PubMed Central

    Marschang, Rachel E.

    2011-01-01

    A large number of viruses have been described in many different reptiles. These viruses include arboviruses that primarily infect mammals or birds as well as viruses that are specific for reptiles. Interest in arboviruses infecting reptiles has mainly focused on the role reptiles may play in the epidemiology of these viruses, especially over winter. Interest in reptile specific viruses has concentrated on both their importance for reptile medicine as well as virus taxonomy and evolution. The impact of many viral infections on reptile health is not known. Koch’s postulates have only been fulfilled for a limited number of reptilian viruses. As diagnostic testing becomes more sensitive, multiple infections with various viruses and other infectious agents are also being detected. In most cases the interactions between these different agents are not known. This review provides an update on viruses described in reptiles, the animal species in which they have been detected, and what is known about their taxonomic positions. PMID:22163336

  15. Respiratory Viruses and Eosinophils: exploring the connections

    PubMed Central

    Rosenberg, Helene F.; Dyer, Kimberly D.; Domachowske, Joseph B.

    2009-01-01

    In this review, we consider the role played by eosinophilic leukocytes in the pathogenesis and pathophysiology of respiratory virus infection. The vast majority of the available information on this topic focuses on respiratory syncytial virus (RSV; Family Paramyxoviridae, genus Pneumovirus), an important pediatric pathogen that infects infants worldwide. There is no vaccine currently available for RSV. A formalininactivated RSV vaccine used in a trial in the 1960s elicited immunopathology in response to natural RSV infection; this has been modeled experimentally, primarily in inbred mice and cotton rats. Eosinophils are recruited to the lung tissue in response to formalin-inactivated RSV vaccine antigens in humans and in experimental models, but they may or may not be involved in promoting the severe clinical sequelae observed. Pulmonary eosinophilia elicited in response to primary RSV infection has also been explored; this response is particularly evident in the youngest human infants and in neonatal mouse models. Although pulmonary eosinophilia is nearly always perceived in a negative light, the specific role played by virus-elicited eosinophils - negative, positive or neutral bystander - remain unclear. Lastly, we consider the data that focus on the role of eosinophils in promoting virus clearance and antiviral host defense, and conclude with a recent study that explores the role of eosinophils themselves as targets of virus infection. (215 words) PMID:19375458

  16. The antiviral potential of interferon-induced cotton rat Mx proteins against orthomyxovirus (influenza), rhabdovirus, and bunyavirus.

    PubMed

    Stertz, Silke; Dittmann, Jan; Blanco, Jorge C G; Pletneva, Lioubov M; Haller, Otto; Kochs, Georg

    2007-10-01

    Influenza A virus (FLUAV) is an important human pathogen able to cause devastating pandemics. Recently, cotton rats have been proposed as an animal model to study the innate immune response against FLUAV and other human pathogens. The interferon (IFN)-induced Mx GTPases are part of the cell-autonomous innate immune response against viruses. We, therefore, tested the antiviral activity of the two cotton rat Mx proteins that were recently identified. The nuclear cotton rat Mx1 protein was found to be a strong inhibitor of FLUAV, whereas the cytoplasmic cotton rat Mx2 protein was inactive. Cotton rat Mx2, but not cotton rat Mx1, was able to inhibit the rhabdovirus vesicular stomatitis virus (VSV) and the bunyavirus Rift Valley fever virus (RVFV) known to replicate in the cytoplasm of infected cells. Thus, cotton rats possess two Mx proteins that have selective antiviral activity that depends on their intracellular localization. We conclude that the Mx status of cotton rats differs from that of conventional inbred mouse strains, which are known to have defective Mx genes. Therefore, cotton rats are a suitable animal model to study experimental infections with FLUAV and other RNA viruses.

  17. Morphogenesis of Bittner Virus

    PubMed Central

    Gay, Frederick W.; Clarke, John K.; Dermott, Evelyn

    1970-01-01

    The morphogenesis of Bittner virus (mouse mammary tumor virus) was studied in sectioned mammary tumor cells. Internal components of the virus (type A particles) were seen being assembled in virus factories close to the nucleus and were also seen forming at the plasma membrane. The particles in virus factories became enveloped by budding through the membrane of cytoplasmic vacuoles which were derived from dilated endoplasmic reticulum. Complete virus particles were liberated from these vacuoles by cell lysis. Particles budding at the plasma membrane were released into intercellular spaces. Maturation of enveloped virus occurred after release, but mature internal components were rarely seen in the cytoplasm before envelopment. Direct cell-to-cell transfer of virus by pinocytosis of budding particles by an adjacent cell was observed, and unusual forms of budding virus which participated in this process are illustrated and described. There was evidence that some virus particles contained cytoplasmic constituents, including ribosomes. Certain features of the structure of internal components are discussed in relation to a recently proposed model for the internal component of the mouse leukemia virus. Intracisternal virus-like particles were occasionally seen in tumor cells, but there was no evidence that these structures were developmentally related to Bittner virus. Images PMID:4193837

  18. Morphogenesis of Bittner virus.

    PubMed

    Gay, F W; Clarke, J K; Dermott, E

    1970-06-01

    The morphogenesis of Bittner virus (mouse mammary tumor virus) was studied in sectioned mammary tumor cells. Internal components of the virus (type A particles) were seen being assembled in virus factories close to the nucleus and were also seen forming at the plasma membrane. The particles in virus factories became enveloped by budding through the membrane of cytoplasmic vacuoles which were derived from dilated endoplasmic reticulum. Complete virus particles were liberated from these vacuoles by cell lysis. Particles budding at the plasma membrane were released into intercellular spaces. Maturation of enveloped virus occurred after release, but mature internal components were rarely seen in the cytoplasm before envelopment. Direct cell-to-cell transfer of virus by pinocytosis of budding particles by an adjacent cell was observed, and unusual forms of budding virus which participated in this process are illustrated and described. There was evidence that some virus particles contained cytoplasmic constituents, including ribosomes. Certain features of the structure of internal components are discussed in relation to a recently proposed model for the internal component of the mouse leukemia virus. Intracisternal virus-like particles were occasionally seen in tumor cells, but there was no evidence that these structures were developmentally related to Bittner virus. PMID:4193837

  19. A Brain Membrane Protein Similar to the Rat src Gene Product

    NASA Astrophysics Data System (ADS)

    Scheinberg, David A.; Strand, Mette

    1981-01-01

    We report the purification to homogeneity of a 20,000-dalton, transformation-related, rat cell membrane protein. This protein, p20, was originally identified in preparations of a defective woolly monkey leukemia virus pseudotype of Kirsten sarcoma virus. The chromatographically purified p20 was an acidic hydrophobic protein, capable of specifically binding GTP (dissociation constant = 15 μ M). This nucleotide binding property and other previously reported characteristics were similar to properties ascribed to the Harvey sarcoma virus src gene product. p20 also appeared similar to this src gene product when immunoprecipitates of both proteins were directly compared by one- and two-dimensional NaDodSO4 gel electrophoreses. However, the proteins were not identical, because their tryptic maps differed. Using a competition radioimmunoassay, we have measured the concentration of p20 in cells, viruses, and rat tissues: p20 was not encoded by rat sarcoma viruses because it was increased only slightly after Kirsten sarcoma virus transformation of rat cells and was not increased in nonrat cells transformed by the Kirsten or Harvey sarcoma virus. Remarkably, of 10 rat tissues examined, p20 was found predominantly in brain, specifically in the membranes.

  20. Respiratory Syncytial Virus Infections

    MedlinePlus

    Respiratory syncytial virus (RSV) causes mild, cold-like symptoms in adults and older healthy children. It can cause serious problems in ... tests can tell if your child has the virus. There is no specific treatment. You should give ...

  1. Viruses and human cancer

    SciTech Connect

    Gallo, R.C.; Haseltine, W.; Klein, G.; Zur Hausen, H.

    1987-01-01

    This book contains papers on the following topics: Immunology and Epidemiology, Biology and Pathogenesis, Models of Pathogenesis and Treatment, Simian and Bovine Retroviruses, Human Papilloma Viruses, EBV and Herpesvirus, and Hepatitis B Virus.

  2. Densonucleosis virus structural proteins.

    PubMed

    Kelly, D C; Moore, N F; Spilling, C R; Barwise, A H; Walker, I O

    1980-10-01

    The protein coats of two densonucleosis viruses (types 1 and 2) were examined by a variety of biophysical, biochemical, and serological techniques. The viruses were 24 nm in diameter, contained at least four polypeptides, were remarkably stable to extremes of pH and denaturing agents, and were serologically closely related. The two viruses could, however, be distinguished serologically and by differences in migration of their structural polypeptides. For each virus the "top component" (i.e., the protein coat minus DNA, found occurring naturally in infections) appeared to have a composition identical to that of the coat of the virus and was a more stable structure. Electrometric titration curves of the virus particles and top components demonstrated that the DNA phosphate in densonucleosis virus particles was neutralized by cations other than basic amino acid side chains of the protein coat. Circular dichroism studies showed that there was a conformational difference between the protein coats of top components and virus particles.

  3. Viruses and Breast Cancer

    PubMed Central

    Lawson, James S.; Heng, Benjamin

    2010-01-01

    Viruses are the accepted cause of many important cancers including cancers of the cervix and anogenital area, the liver, some lymphomas, head and neck cancers and indirectly human immunodeficiency virus associated cancers. For over 50 years, there have been serious attempts to identify viruses which may have a role in breast cancer. Despite these efforts, the establishment of conclusive evidence for such a role has been elusive. However, the development of extremely sophisticated new experimental techniques has allowed the recent development of evidence that human papilloma virus, Epstein-Barr virus, mouse mammary tumor virus and bovine leukemia virus may each have a role in the causation of human breast cancers. This is potentially good news as effective vaccines are already available to prevent infections from carcinogenic strains of human papilloma virus, which causes cancer of the uterine cervix. PMID:24281093

  4. Zika Virus Fact Sheet

    MedlinePlus

    ... 2014 Fact sheets Features Commentaries 2014 Multimedia Contacts Zika virus Fact sheet Updated 6 September 2016 Key facts ... and last for 2-7 days. Complications of Zika virus disease After a comprehensive review of evidence, there ...

  5. Human Parainfluenza Viruses

    MedlinePlus

    ... HPIVs Are Not the Same as Influenza (Flu) Viruses People usually get HPIV infections more often in ... hands, and touching objects or surfaces with the viruses on them then touching your mouth, nose, or ...

  6. Herpes Simplex Virus (HSV)

    MedlinePlus

    ... rashes clinical tools newsletter | contact Share | Herpes Simplex Virus (HSV) A parent's guide to condition and treatment ... skin or mouth sores with the herpes simplex virus (HSV) is called primary herpes. This may be ...

  7. Tumorigenic DNA viruses

    SciTech Connect

    Klein, G.

    1989-01-01

    The eighth volume of Advances in Viral Oncology focuses on the three major DNA virus groups with a postulated or proven tumorigenic potential: papillomaviruses, animal hepatitis viruses, and the Epstein-Bar virus. In the opening chapters, the contributors analyze the evidence that papillomaviruses and animal hepatitis viruses are involved in tumorigenesis and describe the mechanisms that trigger virus-host cell interactions. A detailed section on the Epstein-Barr virus (EBV) - comprising more than half the book - examines the transcription and mRNA processing patterns of the virus genome; the mechanisms by which EBV infects lymphoid and epithelial cells; the immunological aspects of the virus; the actions of EBV in hosts with Acquired Immune Deficiency Syndrome; and the involvement of EBV in the etiology of Burkitt's lymphoma.

  8. Advances in virus research

    SciTech Connect

    Maramorosch, K. ); Murphy, F.A. ); Shatkin, A.J. )

    1988-01-01

    This book contains eight chapters. Some of the titles are: Initiation of viral DNA replication; Vaccinia: virus, vector, vaccine; The pre-S region of hepadnavirus envelope proteins; and Archaebacterial viruses.

  9. West Nile virus

    MedlinePlus

    ... believe West Nile virus is spread when a mosquito bites an infected bird and then bites a person. ... avoid getting West Nile virus infection after a mosquito bite. People in good health generally do not develop ...

  10. Virus Assembly and Maturation

    NASA Astrophysics Data System (ADS)

    Johnson, John E.

    2004-03-01

    We use two techniques to look at three-dimensional virus structure: electron cryomicroscopy (cryoEM) and X-ray crystallography. Figure 1 is a gallery of virus particles whose structures Timothy Baker, one of my former colleagues at Purdue University, used cryoEM to determine. It illustrates the variety of sizes of icosahedral virus particles. The largest virus particle on this slide is the Herpes simplex virus, around 1200Å in diameter; the smallest we examined was around 250Å in diameter. Viruses bear their genomic information either as positive-sense DNA and RNA, double-strand DNA, double-strand RNA, or negative-strand RNA. Viruses utilize the various structure and function "tactics" seen throughout cell biology to replicate at high levels. Many of the biological principles that we consider general were in fact discovered in the context of viruses ...

  11. Avian influenza virus and Newcastle disease virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza virus (AIV) and Newcastle disease virus (NDV) severely impact poultry egg production. Decreased egg yield and hatchability, as well as misshapen eggs, are often observed during infection with AIV and NDV, even with low-virulence strains or in vaccinated flocks. Data suggest that in...

  12. Computer Virus Protection

    ERIC Educational Resources Information Center

    Rajala, Judith B.

    2004-01-01

    A computer virus is a program--a piece of executable code--that has the unique ability to replicate. Like biological viruses, computer viruses can spread quickly and are often difficult to eradicate. They can attach themselves to just about any type of file, and are spread by replicating and being sent from one individual to another. Simply having…

  13. Avian influenza virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza virus (AIV) is type A influenza, which is adapted to an avian host. Although avian influenza has been isolated from numerous avian species, the primary natural hosts for the virus are dabbling ducks, shorebirds, and gulls. The virus can be found world-wide in these species and in o...

  14. Respiratory Syncytial Virus

    MedlinePlus

    ... Palsy: Shannon's Story" 5 Things to Know About Zika & Pregnancy Respiratory Syncytial Virus KidsHealth > For Parents > Respiratory Syncytial Virus Print A ... often get it when older kids carry the virus home from school and pass it to ... often happen in epidemics that last from late fall through early spring. ...

  15. Zika virus - an overview.

    PubMed

    Zanluca, Camila; Dos Santos, Claudia Nunes Duarte

    2016-05-01

    Zika virus (ZIKV) is currently one of the most important emerging viruses in the world. Recently, it has caused outbreaks and epidemics, and has been associated with severe clinical manifestations and congenital malformations. However to date, little is known about the pathogenicity of the virus and the consequences of ZIKV infection. In this paper, we provide an overview of the current knowledge on ZIKV.

  16. The taxonomy of viruses should include viruses.

    PubMed

    Calisher, Charles H

    2016-05-01

    Having lost sight of its goal, the International Committee on Taxonomy of Viruses has redoubled its efforts. That goal is to arrive at a consensus regarding virus classification, i.e., proper placement of viruses in a hierarchical taxonomic scheme; not an easy task given the wide variety of recognized viruses. Rather than suggesting a continuation of the bureaucratic machinations of the past, this opinion piece is a call for insertion of common sense in sorting out the avalanche of information already, and soon-to-be, accrued data. In this way information about viruses ideally would be taxonomically correct as well as useful to working virologists and journal editors, rather than being lost, minimized, or ignored.

  17. Morphological evidence for natural poxvirus infection in rats

    NASA Technical Reports Server (NTRS)

    Kraft, L. M.; Dantoni Damelio, E.; Damelio, F. E.

    1982-01-01

    Focal inflammatory and desquamating lesions were seen in the nasal mucosa of rats that were flown aboard the Soviet satellite, Cosmos 1129, in 1979 and in the ground based controls. The infection was clinically inapparent. Electron microscopic examination revealed the presence of poxvirus virions in desquamating cells. The specific poxvirus involved could not be identified. The lesions appeared to be similar to those described by others in rats experimentally infected with mousepox (infectious ectromelia) virus by the intranasal route.

  18. Phylogenetic Relationship of Necoclí Virus to Other South American Hantaviruses (Bunyaviridae: Hantavirus).

    PubMed

    Montoya-Ruiz, Carolina; Cajimat, Maria N B; Milazzo, Mary Louise; Diaz, Francisco J; Rodas, Juan David; Valbuena, Gustavo; Fulhorst, Charles F

    2015-07-01

    The results of a previous study suggested that Cherrie's cane rat (Zygodontomys cherriei) is the principal host of Necoclí virus (family Bunyaviridae, genus Hantavirus) in Colombia. Bayesian analyses of complete nucleocapsid protein gene sequences and complete glycoprotein precursor gene sequences in this study confirmed that Necoclí virus is phylogenetically closely related to Maporal virus, which is principally associated with the delicate pygmy rice rat (Oligoryzomys delicatus) in western Venezuela. In pairwise comparisons, nonidentities between the complete amino acid sequence of the nucleocapsid protein of Necoclí virus and the complete amino acid sequences of the nucleocapsid proteins of other hantaviruses were ≥8.7%. Likewise, nonidentities between the complete amino acid sequence of the glycoprotein precursor of Necoclí virus and the complete amino acid sequences of the glycoprotein precursors of other hantaviruses were ≥11.7%. Collectively, the unique association of Necoclí virus with Z. cherriei in Colombia, results of the Bayesian analyses of complete nucleocapsid protein gene sequences and complete glycoprotein precursor gene sequences, and results of the pairwise comparisons of amino acid sequences strongly support the notion that Necoclí virus represents a novel species in the genus Hantavirus. Further work is needed to determine whether Calabazo virus (a hantavirus associated with Z. brevicauda cherriei in Panama) and Necoclí virus are conspecific.

  19. Phylogenetic Relationship of Necoclí Virus to Other South American Hantaviruses (Bunyaviridae: Hantavirus)

    PubMed Central

    Montoya-Ruiz, Carolina; Cajimat, Maria N. B.; Milazzo, Mary Louise; Diaz, Francisco J.; Rodas, Juan David; Valbuena, Gustavo

    2015-01-01

    Abstract The results of a previous study suggested that Cherrie's cane rat (Zygodontomys cherriei) is the principal host of Necoclí virus (family Bunyaviridae, genus Hantavirus) in Colombia. Bayesian analyses of complete nucleocapsid protein gene sequences and complete glycoprotein precursor gene sequences in this study confirmed that Necoclí virus is phylogenetically closely related to Maporal virus, which is principally associated with the delicate pygmy rice rat (Oligoryzomys delicatus) in western Venezuela. In pairwise comparisons, nonidentities between the complete amino acid sequence of the nucleocapsid protein of Necoclí virus and the complete amino acid sequences of the nucleocapsid proteins of other hantaviruses were ≥8.7%. Likewise, nonidentities between the complete amino acid sequence of the glycoprotein precursor of Necoclí virus and the complete amino acid sequences of the glycoprotein precursors of other hantaviruses were ≥11.7%. Collectively, the unique association of Necoclí virus with Z. cherriei in Colombia, results of the Bayesian analyses of complete nucleocapsid protein gene sequences and complete glycoprotein precursor gene sequences, and results of the pairwise comparisons of amino acid sequences strongly support the notion that Necoclí virus represents a novel species in the genus Hantavirus. Further work is needed to determine whether Calabazo virus (a hantavirus associated with Z. brevicauda cherriei in Panama) and Necoclí virus are conspecific. PMID:26186516

  20. Viruses of asparagus.

    PubMed

    Tomassoli, Laura; Tiberini, Antonio; Vetten, Heinrich-Josef

    2012-01-01

    The current knowledge on viruses infecting asparagus (Asparagus officinalis) is reviewed. Over half a century, nine virus species belonging to the genera Ilarvirus, Cucumovirus, Nepovirus, Tobamovirus, Potexvirus, and Potyvirus have been found in this crop. The potyvirus Asparagus virus 1 (AV1) and the ilarvirus Asparagus virus 2 (AV2) are widespread and negatively affect the economic life of asparagus crops reducing yield and increasing the susceptibility to biotic and abiotic stress. The main properties and epidemiology of AV1 and AV2 as well as diagnostic techniques for their detection and identification are described. Minor viruses and control are briefly outlined.

  1. Viruses of asparagus.

    PubMed

    Tomassoli, Laura; Tiberini, Antonio; Vetten, Heinrich-Josef

    2012-01-01

    The current knowledge on viruses infecting asparagus (Asparagus officinalis) is reviewed. Over half a century, nine virus species belonging to the genera Ilarvirus, Cucumovirus, Nepovirus, Tobamovirus, Potexvirus, and Potyvirus have been found in this crop. The potyvirus Asparagus virus 1 (AV1) and the ilarvirus Asparagus virus 2 (AV2) are widespread and negatively affect the economic life of asparagus crops reducing yield and increasing the susceptibility to biotic and abiotic stress. The main properties and epidemiology of AV1 and AV2 as well as diagnostic techniques for their detection and identification are described. Minor viruses and control are briefly outlined. PMID:22682173

  2. Serodiagnosis for Tumor Viruses

    PubMed Central

    Morrison, Brian J.; Labo, Nazzarena; Miley, Wendell J.; Whitby, Denise

    2015-01-01

    The known human tumor viruses include the DNA viruses Epstein-Barr virus, Kaposi sarcoma herpesvirus, Merkel cell polyomavirus, human papillomavirus, and hepatitis B virus. RNA tumor viruses include Human T-cell lymphotrophic virus type-1 and hepatitis C virus. The serological identification of antigens/antibodies in plasma serum is a rapidly progressing field with utility for both scientists and clinicians. Serology is useful for conducting seroepidemiology studies and to inform on the pathogenesis and host immune response to a particular viral agent. Clinically, serology is useful for diagnosing current or past infection and for aiding in clinical management decisions. Serology is useful for screening blood donations for infectious agents and for monitoring the outcome of vaccination against these viruses. Serodiagnosis of human tumor viruses has improved in recent years with increased specificity and sensitivity of the assays, as well as reductions in cost and the ability to assess multiple antibody/antigens in single assays. Serodiagnosis of tumor viruses plays an important role in our understanding of the prevalence and transmission of these viruses and ultimately in the ability to develop treatments/preventions for these globally important diseases. PMID:25843726

  3. Discovering novel zoonotic viruses.

    PubMed

    Wang, Lin-Fa

    2011-07-01

    From the emergence of Hendra virus and Menangle virus in Australia to the global pandemics of severe acute respiratory syndrome and influenza viruses (both H5N1 and H1N1), there has been a surge of zoonotic virus outbreaks in the last two decades. Although the drivers for virus emergence remain poorly understood, the rate of discovery of new viruses is accelerating. This is due to a combination of true emergence of new pathogens and the advance of new technologies making rapid detection and characterisation possible. While molecular approaches will continue to lead the way in virus discovery, other technological platforms are required to increase the chance of success. The lessons learnt in the last 20 years confirm that the One Health approach, involving inclusive collaborations between physicians, veterinarians and other health and environmental professionals, will be the key to combating future zoonotic disease outbreaks.

  4. Rat coronaviruses infect rat alveolar type I epithelial cells and induce expression of CXC chemokines

    PubMed Central

    Miura, Tanya A.; Wang, Jieru; Holmes, Kathryn V.; Mason, Robert J.

    2007-01-01

    We analyzed the ability of two rat coronavirus (RCoV) strains, sialodacryoadenitis virus (SDAV) and Parker’s RCoV (RCoV-P), to infect rat alveolar type I cells and induce chemokine expression. Primary rat alveolar type II cells were transdifferentiated into the type I cell phenotype. Type I cells were productively infected with SDAV and RCoV-P, and both live virus and UV-inactivated virus induced mRNA and protein expression of three CXC chemokines: CINC-2, CINC-3, and LIX, which are neutrophil chemoattractants. Dual immunolabeling of type I cells for viral antigen and CXC chemokines showed that chemokines were expressed primarily by uninfected cells. Virus-induced chemokine expression was reduced by the IL-1 receptor antagonist, suggesting that IL-1 produced by infected cells induces uninfected cells to express chemokines. Primary cultures of alveolar epithelial cells are an important model for the early events in viral infection that lead to pulmonary inflammation. PMID:17804032

  5. Virus-Associated Lymphomagenesis

    PubMed Central

    Tarantul, V. Z.

    2006-01-01

    At least 2 billion people are affected by viral infections worldwide. The infections induce a lot of various human diseases and are one of the main causes of human mortality. In particular, they can lead to development of various human cancers. Up to 15-20% of human cancer incidence can be attributed to viruses. Although viral infections are very common in the general population, only few of them result in clinically relevant lesions. Certain associations between virus infections and malignancy are strong and irrefutable, the others are still speculative. The criteria most often used for determining the causality are the consistence of the association, either epidemiologic or at the molecular level, and oncogenicity of viruses or particular viral genes in animal models or cell cultures. Due to some ambiguity of such a determination, it is instructive to consider by specific cases what evidence is generally accepted as sufficient to establish a causal relation between virus and cancer. Lymphomas are one of the best studied cancer types closely associated with a small but definite range of viruses. Numerous data show a close interrelation between lymphomagenesis and infection by such viruses as Kaposi’s sarcoma herpesvirus (KSHV), Epstein-Barr virus (EBV), hepatitis C virus (HCV), human T-cell leukemia virus (HTLV), and human immunodeficiency virus (HIV). For instance, experiments on monkeys artificially infected with viruses and data on anti-cancer effect of specific antiviral preparations strongly suggest the involvement of viruses in lymphoma development. The present review is devoted to the association of different viruses with human lymphomas and to viral genes potentially involved in the neoplastic process. The recognition of virus involvement in lymphomagenesis may facilitate new strategies for cancer therapy, diagnosis and screening and can lead to a reduction in the number of individuals at risk of disease. PMID:23674972

  6. Venezuelan equine encephalitis virus, southern Mexico.

    PubMed

    Estrada-Franco, José G; Navarro-Lopez, Roberto; Freier, Jerome E; Cordova, Dionicio; Clements, Tamara; Moncayo, Abelardo; Kang, Wenli; Gomez-Hernandez, Carlos; Rodriguez-Dominguez, Gabriela; Ludwig, George V; Weaver, Scott C

    2004-12-01

    Equine epizootics of Venezuelan equine encephalitis (VEE) occurred in the southern Mexican states of Chiapas in 1993 and Oaxaca in 1996. To assess the impact of continuing circulation of VEE virus (VEEV) on human and animal populations, serologic and viral isolation studies were conducted in 2000 to 2001 in Chiapas State. Human serosurveys and risk analyses indicated that long-term endemic transmission of VEEV occurred among villages with seroprevalence levels of 18% to 75% and that medical personnel had a high risk for VEEV exposure. Seroprevalence in wild animals suggested cotton rats as possible reservoir hosts in the region. Virus isolations from sentinel animals and genetic characterizations of these strains indicated continuing circulation of a subtype IE genotype, which was isolated from equines during the recent VEE outbreaks. These data indicate long-term enzootic and endemic VEEV circulation in the region and continued risk for disease in equines and humans. PMID:15663847

  7. New Hosts of The Lassa Virus.

    PubMed

    Olayemi, Ayodeji; Cadar, Daniel; Magassouba, N'Faly; Obadare, Adeoba; Kourouma, Fode; Oyeyiola, Akinlabi; Fasogbon, Samuel; Igbokwe, Joseph; Rieger, Toni; Bockholt, Sabrina; Jérôme, Hanna; Schmidt-Chanasit, Jonas; Garigliany, Mutien; Lorenzen, Stephan; Igbahenah, Felix; Fichet, Jean-Nicolas; Ortsega, Daniel; Omilabu, Sunday; Günther, Stephan; Fichet-Calvet, Elisabeth

    2016-01-01

    Lassa virus (LASV) causes a deadly haemorrhagic fever in humans, killing several thousand people in West Africa annually. For 40 years, the Natal multimammate rat, Mastomys natalensis, has been assumed to be the sole host of LASV. We found evidence that LASV is also hosted by other rodent species: the African wood mouse Hylomyscus pamfi in Nigeria, and the Guinea multimammate mouse Mastomys erythroleucus in both Nigeria and Guinea. Virus strains from these animals were isolated in the BSL-4 laboratory and fully sequenced. Phylogenetic analyses of viral genes coding for glycoprotein, nucleoprotein, polymerase and matrix protein show that Lassa strains detected in M. erythroleucus belong to lineages III and IV. The strain from H. pamfi clusters close to lineage I (for S gene) and between II &III (for L gene). Discovery of new rodent hosts has implications for LASV evolution and its spread into new areas within West Africa. PMID:27140942

  8. New Hosts of The Lassa Virus

    PubMed Central

    Olayemi, Ayodeji; Cadar, Daniel; Magassouba, N’Faly; Obadare, Adeoba; Kourouma, Fode; Oyeyiola, Akinlabi; Fasogbon, Samuel; Igbokwe, Joseph; Rieger, Toni; Bockholt, Sabrina; Jérôme, Hanna; Schmidt-Chanasit, Jonas; Garigliany, Mutien; Lorenzen, Stephan; Igbahenah, Felix; Fichet, Jean-Nicolas; Ortsega, Daniel; Omilabu, Sunday; Günther, Stephan; Fichet-Calvet, Elisabeth

    2016-01-01

    Lassa virus (LASV) causes a deadly haemorrhagic fever in humans, killing several thousand people in West Africa annually. For 40 years, the Natal multimammate rat, Mastomys natalensis, has been assumed to be the sole host of LASV. We found evidence that LASV is also hosted by other rodent species: the African wood mouse Hylomyscus pamfi in Nigeria, and the Guinea multimammate mouse Mastomys erythroleucus in both Nigeria and Guinea. Virus strains from these animals were isolated in the BSL-4 laboratory and fully sequenced. Phylogenetic analyses of viral genes coding for glycoprotein, nucleoprotein, polymerase and matrix protein show that Lassa strains detected in M. erythroleucus belong to lineages III and IV. The strain from H. pamfi clusters close to lineage I (for S gene) and between II & III (for L gene). Discovery of new rodent hosts has implications for LASV evolution and its spread into new areas within West Africa. PMID:27140942

  9. Genetic labeling of both the axons of transduced, glutamatergic neurons in rat postrhinal cortex and their postsynaptic neurons in other neocortical areas by herpes simplex virus vectors that coexpress an axon-targeted β-galactosidase and wheat germ agglutinin from a vesicular glutamate transporter-1 promoter.

    PubMed

    Zhang, Guo-rong; Cao, Haiyan; Li, Xu; Zhao, Hua; Geller, Alfred I

    2010-11-18

    Neuronal circuits comprise the foundation for neuronal physiology and synaptic plasticity, and thus for consequent behaviors and learning, but our knowledge of neocortical circuits is incomplete. Mapping neocortical circuits is a challenging problem because these circuits contain large numbers of neurons, a high density of synapses, and numerous classes and subclasses of neurons that form many different types of synapses. Expression of specific genetic tracers in small numbers of specific subclasses of neocortical neurons has the potential to map neocortical circuits. Suitable genetic tracers have been established in neurons in subcortical areas, but application to neocortical circuits has been limited. Enabling this approach, Herpes Simplex Virus (HSV-1) plasmid (amplicon) vectors can transduce small numbers of neurons in a specific neocortical area. Further, expression of a particular genetic tracer can be restricted to specific subclasses of neurons; in particular, the vesicular glutamate transporter-1 (VGLUT1) promoter supports expression in VGLUT1-containing glutamatergic neurons in rat postrhinal (POR) cortex. Here, we show that expression of an axon-targeted β-galactosidase (β-gal) from such vectors supports mapping specific commissural and associative projections of the transduced neurons in POR cortex. Further, coexpression of wheat germ agglutinin (WGA) and an axon-targeted β-gal supports mapping both specific projections of the transduced neurons and identifying specific postsynaptic neurons for the transduced neurons. The neocortical circuit mapping capabilities developed here may support mapping specific neocortical circuits that have critical roles in cognitive learning.

  10. Genome-wide comparison of cowpox viruses reveals a new clade related to Variola virus.

    PubMed

    Dabrowski, Piotr Wojtek; Radonić, Aleksandar; Kurth, Andreas; Nitsche, Andreas

    2013-01-01

    Zoonotic infections caused by several orthopoxviruses (OPV) like monkeypox virus or vaccinia virus have a significant impact on human health. In Europe, the number of diagnosed infections with cowpox viruses (CPXV) is increasing in animals as well as in humans. CPXV used to be enzootic in cattle; however, such infections were not being diagnosed over the last decades. Instead, individual cases of cowpox are being found in cats or exotic zoo animals that transmit the infection to humans. Both animals and humans reveal local exanthema on arms and legs or on the face. Although cowpox is generally regarded as a self-limiting disease, immunosuppressed patients can develop a lethal systemic disease resembling smallpox. To date, only limited information on the complex and, compared to other OPV, sparsely conserved CPXV genomes is available. Since CPXV displays the widest host range of all OPV known, it seems important to comprehend the genetic repertoire of CPXV which in turn may help elucidate specific mechanisms of CPXV pathogenesis and origin. Therefore, 22 genomes of independent CPXV strains from clinical cases, involving ten humans, four rats, two cats, two jaguarundis, one beaver, one elephant, one marah and one mongoose, were sequenced by using massive parallel pyrosequencing. The extensive phylogenetic analysis showed that the CPXV strains sequenced clearly cluster into several distinct clades, some of which are closely related to Vaccinia viruses while others represent different clades in a CPXV cluster. Particularly one CPXV clade is more closely related to Camelpox virus, Taterapox virus and Variola virus than to any other known OPV. These results support and extend recent data from other groups who postulate that CPXV does not form a monophyletic clade and should be divided into multiple lineages.

  11. Genome-wide comparison of cowpox viruses reveals a new clade related to Variola virus.

    PubMed

    Dabrowski, Piotr Wojtek; Radonić, Aleksandar; Kurth, Andreas; Nitsche, Andreas

    2013-01-01

    Zoonotic infections caused by several orthopoxviruses (OPV) like monkeypox virus or vaccinia virus have a significant impact on human health. In Europe, the number of diagnosed infections with cowpox viruses (CPXV) is increasing in animals as well as in humans. CPXV used to be enzootic in cattle; however, such infections were not being diagnosed over the last decades. Instead, individual cases of cowpox are being found in cats or exotic zoo animals that transmit the infection to humans. Both animals and humans reveal local exanthema on arms and legs or on the face. Although cowpox is generally regarded as a self-limiting disease, immunosuppressed patients can develop a lethal systemic disease resembling smallpox. To date, only limited information on the complex and, compared to other OPV, sparsely conserved CPXV genomes is available. Since CPXV displays the widest host range of all OPV known, it seems important to comprehend the genetic repertoire of CPXV which in turn may help elucidate specific mechanisms of CPXV pathogenesis and origin. Therefore, 22 genomes of independent CPXV strains from clinical cases, involving ten humans, four rats, two cats, two jaguarundis, one beaver, one elephant, one marah and one mongoose, were sequenced by using massive parallel pyrosequencing. The extensive phylogenetic analysis showed that the CPXV strains sequenced clearly cluster into several distinct clades, some of which are closely related to Vaccinia viruses while others represent different clades in a CPXV cluster. Particularly one CPXV clade is more closely related to Camelpox virus, Taterapox virus and Variola virus than to any other known OPV. These results support and extend recent data from other groups who postulate that CPXV does not form a monophyletic clade and should be divided into multiple lineages. PMID:24312452

  12. [The great virus comeback].

    PubMed

    Forterre, Patrick

    2013-01-01

    Viruses have been considered for a long time as by-products of biological evolution. This view is changing now as a result of several recent discoveries. Viral ecologists have shown that viral particles are the most abundant biological entities on our planet, whereas metagenomic analyses have revealed an unexpected abundance and diversity of viral genes in the biosphere. Comparative genomics have highlighted the uniqueness of viral sequences, in contradiction with the traditional view of viruses as pickpockets of cellular genes. On the contrary, cellular genomes, especially eukaryotic ones, turned out to be full of genes derived from viruses or related elements (plasmids, transposons, retroelements and so on). The discovery of unusual viruses infecting archaea has shown that the viral world is much more diverse than previously thought, ruining the traditional dichotomy between bacteriophages and viruses. Finally, the discovery of giant viruses has blurred the traditional image of viruses as small entities. Furthermore, essential clues on virus history have been obtained in the last ten years. In particular, structural analyses of capsid proteins have uncovered deeply rooted homologies between viruses infecting different cellular domains, suggesting that viruses originated before the last universal common ancestor (LUCA). These studies have shown that several lineages of viruses originated independently, i.e., viruses are polyphyletic. From the time of LUCA, viruses have coevolved with their hosts, and viral lineages can be viewed as lianas wrapping around the trunk, branches and leaves of the tree of life. Although viruses are very diverse, with genomes encoding from one to more than one thousand proteins, they can all be simply defined as organisms producing virions. Virions themselves can be defined as infectious particles made of at least one protein associated with the viral nucleic acid, endowed with the capability to protect the viral genome and ensure its

  13. Polarized entry and release in epithelial cells of Black Creek Canal virus, a New World hantavirus.

    PubMed

    Ravkov, E V; Nichol, S T; Compans, R W

    1997-02-01

    Black Creek Canal (BCC) virus is a newly identified hantavirus from Florida which is carried by the cotton rat (Sigmodon hispidus) and is associated with hantavirus pulmonary syndrome (HPS). We have investigated the interaction of BCC virus with polarized epithelial cells to examine whether entry and release of this virus occur at specific plasma membrane domains. The polarized Vero C1008 monkey kidney cell line was grown on permeable filters and infected with BCC virus either through the apical or basolateral surface. As shown by indirect immunofluorescence and radioimmunoprecipitation analysis, cells infected through the apical surface demonstrated a high level of susceptibility to BCC virus infection. In contrast, Vero C1008 cells infected basolaterally exhibited a barely detectable level of BCC virus-synthesized proteins. Titration of virus from apical and basolateral media of infected cells has demonstrated that virus titers released from the apical surface are about 1,200-fold greater than the titer of virus released into the basolateral media. The site of BCC virus release from polarized cells is, therefore, different from that previously described for release of other members of the family Bunyaviridae and may reflect one of the determinants of hantavirus pathogenesis. In addition, we have shown that BCC viral glycoproteins are expressed at the plasma membrane on the apical surface of polarized cells. Electron microscopy studies of the infected cells revealed evidence of BCC virus budding at the plasma membrane. This strongly indicates that, in contrast to most other members of the Bunyaviridae, BCC virus is assembled at the plasma membrane. Since the same site of virus assembly was recently described for Sin Nombre virus, it is likely that all of the new American hantaviruses associated with HPS utilize this same type of virus maturation.

  14. Viruses of botrytis.

    PubMed

    Pearson, Michael N; Bailey, Andrew M

    2013-01-01

    Botrytis cinerea (gray mold) is one of the most widespread and destructive fungal diseases of horticultural crops. Propagation and dispersal is usually by asexual conidia but the sexual stage (Botryotinia fuckeliana (de Bary) Whetzel) also occurs in nature. DsRNAs, indicative of virus infection, are common in B. cinerea, but only four viruses (Botrytis virus F (BVF), Botrytis virus X (BVX), Botrytis cinerea mitovirus 1 (BcMV1), and Botrytis porri RNA virus) have been sequenced. BVF and BVX are unusual mycoviruses being ssRNA flexous rods and have been designated the type species of the genera Mycoflexivirus and Botrexvirus (family Betaflexivirdae), respectively. The reported effects of viruses on Botrytis range from negligible to severe, with Botrytis cinerea mitovirus 1 causing hypovirulence. Little is currently known about the effects of viruses on Botrytis metabolism but recent complete sequencing of the B. cinerea genome now provides an opportunity to investigate the host-pathogen interactions at the molecular level. There is interest in the possible use of mycoviruses as biological controls for Botrytis because of the common problem of fungicide resistance. Unfortunately, hyphal anastomosis is the only known mechanism of horizontal virus transmission and the large number of vegetative incompatibility groups in Botrytis is a potential constraint on the spread of an introduced virus. Although some Botrytis viruses, such as BVF and BVX, are known to have international distribution, there is a distinct lack of epidemiological data and the means of spread are unknown.

  15. RNA Viruses Infecting Pest Insects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    RNA viruses are viruses whose genetic material is ribonucleic acid (RNA). RNA viruses may be double or single-stranded based on the type of RNA they contain. Single-stranded RNA viruses can be further grouped into negative sense or positive-sense viruses according to the polarity of their RNA. Fur...

  16. Postmortem stability of Ebola virus.

    PubMed

    Prescott, Joseph; Bushmaker, Trenton; Fischer, Robert; Miazgowicz, Kerri; Judson, Seth; Munster, Vincent J

    2015-05-01

    The ongoing Ebola virus outbreak in West Africa has highlighted questions regarding stability of the virus and detection of RNA from corpses. We used Ebola virus-infected macaques to model humans who died of Ebola virus disease. Viable virus was isolated <7 days posteuthanasia; viral RNA was detectable for 10 weeks.

  17. Helminth parasites in black rats (Rattus rattus) and brown rats (Rattus norvegicus) from different environments in the Netherlands

    PubMed Central

    Franssen, Frits; Swart, Arno; van Knapen, Frans; van der Giessen, Joke

    2016-01-01

    Background Rattus norvegicus (brown rat) and Rattus rattus (black rat) are known carriers of bacteria, viruses, and parasites of zoonotic and veterinary importance. Moreover, rats may play a role in the transmission of muscle larvae of the zoonotic nematode Trichinella spiralis to farm animals. We aimed to study the intestinal and intramuscular helminths in wild rats from three different environments to assess the relevance of rats as carrier of zoonotic parasites for public health. Materials and methods Wild brown rats (117 individuals) and black rats (44 individuals) were captured at farms, in suburban and in rural environments in the Netherlands. Intestinal helminths were isolated and identified morphologically. Artificial digestion was used to isolate muscle larvae. Results and discussion Morphological analysis of rat intestinal contents yielded six nematode species (Syphacia muris, Heterakis spumosa, Aonchotheca murissylvatici, Trichuris muris, Nippostrongylus brasiliensis, and Strongyloides sp.), three cestode species (Hymenolepis diminuta, H. nana and Hymenolepis (=Rodentolepis) fraterna), and four trematode species (Plagiorchis muris, Plagiorchis proximus, Echinostoma chloropodis, and Notocotylus imbricatus). Black rats at farms displayed the lowest intestinal helminth species variation (six species) and carried overall on average 0.93 species simultaneously. In comparison, brown rats at farms carried seven helminth species and 1.91 species simultaneously. Brown rats from suburban environments displayed the highest species variation (11 species) at 1.82 simultaneous helminth species. Absence of trematodes from rats at farms may suggest limited exchange of rats between farms and surrounding wet rural environments. We report four species of veterinary (Syphacia muris) or zoonotic relevance (Hymenolepis diminuta, Hymenolepis nana and Plagiorchis muris). We did not find Trichinella muscle larvae, consistent with long-term prevalence in Dutch wild rats. PMID

  18. Water system virus detection

    NASA Technical Reports Server (NTRS)

    Fraser, A. S.; Wells, A. F.; Tenoso, H. J. (Inventor)

    1978-01-01

    The performance of a waste water reclamation system is monitored by introducing a non-pathogenic marker virus, bacteriophage F2, into the waste-water prior to treatment and, thereafter, testing the reclaimed water for the presence of the marker virus. A test sample is first concentrated by absorbing any marker virus onto a cellulose acetate filter in the presence of a trivalent cation at low pH and then flushing the filter with a limited quantity of a glycine buffer solution to desorb any marker virus present on the filter. Photo-optical detection of indirect passive immune agglutination by polystyrene beads indicates the performance of the water reclamation system in removing the marker virus. A closed system provides for concentrating any marker virus, initiating and monitoring the passive immune agglutination reaction, and then flushing the system to prepare for another sample.

  19. Constructing computer virus phylogenies

    SciTech Connect

    Goldberg, L.A.; Goldberg, P.W.; Phillips, C.A.; Sorkin, G.B.

    1996-03-01

    There has been much recent algorithmic work on the problem of reconstructing the evolutionary history of biological species. Computer virus specialists are interested in finding the evolutionary history of computer viruses--a virus is often written using code fragments from one or more other viruses, which are its immediate ancestors. A phylogeny for a collection of computer viruses is a directed acyclic graph whose nodes are the viruses and whose edges map ancestors to descendants and satisfy the property that each code fragment is ``invented`` only once. To provide a simple explanation for the data, we consider the problem of constructing such a phylogeny with a minimal number of edges. In general, this optimization problem cannot be solved in quasi-polynomial time unless NQP=QP; we present positive and negative results for associated approximated problems. When tree solutions exist, they can be constructed and randomly sampled in polynomial time.

  20. Viruses within animal genomes.

    PubMed

    De Brognier, A; Willems, L

    2016-04-01

    Viruses and their hosts can co-evolve to reach a fragile equilibrium that allows the survival of both. An excess of pathogenicity in the absence of a reservoir would be detrimental to virus survival. A significant proportion of all animal genomes has been shaped by the insertion of viruses that subsequently became 'fossilised'. Most endogenous viruses have lost the capacity to replicate via an infectious cycle and now replicate passively. The insertion of endogenous viruses has contributed to the evolution of animal genomes, for example in the reproductive biology of mammals. However, spontaneous viral integration still occasionally occurs in a number of virus-host systems. This constitutes a potential risk to host survival but also provides an opportunity for diversification and evolution.

  1. Viruses of lower vertebrates.

    PubMed

    Essbauer, S; Ahne, W

    2001-08-01

    Viruses of lower vertebrates recently became a field of interest to the public due to increasing epizootics and economic losses of poikilothermic animals. These were reported worldwide from both wildlife and collections of aquatic poikilothermic animals. Several RNA and DNA viruses infecting fish, amphibians and reptiles have been studied intensively during the last 20 years. Many of these viruses induce diseases resulting in important economic losses of lower vertebrates, especially in fish aquaculture. In addition, some of the DNA viruses seem to be emerging pathogens involved in the worldwide decline in wildlife. Irido-, herpes- and polyomavirus infections may be involved in the reduction in the numbers of endangered amphibian and reptile species. In this context the knowledge of several important RNA viruses such as orthomyxo-, paramyxo-, rhabdo-, retro-, corona-, calici-, toga-, picorna-, noda-, reo- and birnaviruses, and DNA viruses such as parvo-, irido-, herpes-, adeno-, polyoma- and poxviruses, is described in this review. PMID:11550762

  2. Viruses in Antarctic lakes

    NASA Technical Reports Server (NTRS)

    Kepner, R. L. Jr; Wharton, R. A. Jr; Suttle, C. A.; Wharton RA, J. r. (Principal Investigator)

    1998-01-01

    Water samples collected from four perennially ice-covered Antarctic lakes during the austral summer of 1996-1997 contained high densities of extracellular viruses. Many of these viruses were found to be morphologically similar to double-stranded DNA viruses that are known to infect algae and protozoa. These constitute the first observations of viruses in perennially ice-covered polar lakes. The abundance of planktonic viruses and data suggesting substantial production potential (relative to bacteria] secondary and photosynthetic primary production) indicate that viral lysis may be a major factor in the regulation of microbial populations in these extreme environments. Furthermore, we suggest that Antarctic lakes may be a reservoir of previously undescribed viruses that possess novel biological and biochemical characteristics.

  3. The human oncogenic viruses

    SciTech Connect

    Luderer, A.A.; Weetall, H.H

    1986-01-01

    This book contains eight selections. The titles are: Cytogenetics of the Leukemias and Lymphomas; Cytogenetics of Solid Tumors: Renal Cell Carcinoma, Malignant Melanoma, Retinoblastoma, and Wilms' Tumor; Elucidation of a Normal Function for a Human Proto-Oncogene; Detection of HSV-2 Genes and Gene Products in Cervical Neoplasia; Papillomaviruses in Anogennital Neoplasms; Human Epstein-Barr Virus and Cancer; Hepatitis B Virus and Hepatocellular Carcinoma; and Kaposi's Sarcoma: Acquired Immunodeficiency Syndrome (AIDS) and Associated Viruses.

  4. Water system virus detection

    NASA Technical Reports Server (NTRS)

    Fraser, A. S.; Wells, A. F.; Tenoso, H. J.

    1975-01-01

    A monitoring system developed to test the capability of a water recovery system to reject the passage of viruses into the recovered water is described. A nonpathogenic marker virus, bacteriophage F2, is fed into the process stream before the recovery unit and the reclaimed water is assayed for its presence. Detection of the marker virus consists of two major components, concentration and isolation of the marker virus, and detection of the marker virus. The concentration system involves adsorption of virus to cellulose acetate filters in the presence of trivalent cations and low pH with subsequent desorption of the virus using volumes of high pH buffer. The detection of the virus is performed by a passive immune agglutination test utilizing specially prepared polystyrene particles. An engineering preliminary design was performed as a parallel effort to the laboratory development of the marker virus test system. Engineering schematics and drawings of a fully functional laboratory prototype capable of zero-G operation are presented. The instrument consists of reagent pump/metering system, reagent storage containers, a filter concentrator, an incubation/detector system, and an electronic readout and control system.

  5. [Zika virus epidemic].

    PubMed

    Kronborg, Gitte; Fomsgaard, Anders

    2016-03-21

    Zika virus is endemic in several parts of the world. February 1, 2016 Zika virus was declared a public health emergency by the WHO. This declaration is mainly due to a convincing association between Zika virus infection during pregnancy and birth defects, like microcephaly, among some of the newborns. Imported cases of Zika virus infection to North America, Europe and Denmark have been described. The infection in itself is mild and self-limiting. The available diagnostic methods are under development, validation and evaluation. In Denmark, some promising diagnostics are available at Statens Serum Institut.

  6. Inactivated ORF virus shows antifibrotic activity and inhibits human hepatitis B virus (HBV) and hepatitis C virus (HCV) replication in preclinical models.

    PubMed

    Paulsen, Daniela; Urban, Andreas; Knorr, Andreas; Hirth-Dietrich, Claudia; Siegling, Angela; Volk, Hans-Dieter; Mercer, Andrew A; Limmer, Andreas; Schumak, Beatrix; Knolle, Percy; Ruebsamen-Schaeff, Helga; Weber, Olaf

    2013-01-01

    Inactivated orf virus (iORFV), strain D1701, is a potent immune modulator in various animal species. We recently demonstrated that iORFV induces strong antiviral activity in animal models of acute and chronic viral infections. In addition, we found D1701-mediated antifibrotic effects in different rat models of liver fibrosis. In the present study, we compare iORFV derived from two different strains of ORFV, D1701 and NZ2, respectively, with respect to their antifibrotic potential as well as their potential to induce an antiviral response controlling infections with the hepatotropic pathogens hepatitis C virus (HCV) and hepatitis B virus (HBV). Both strains of ORFV showed anti-viral activity against HCV in vitro and against HBV in a transgenic mouse model without signs of necro-inflammation in vivo. Our experiments suggest that the absence of liver damage is potentially mediated by iORFV-induced downregulation of antigen cross-presentation in liver sinus endothelial cells. Furthermore, both strains showed significant anti-fibrotic activity in rat models of liver fibrosis. iORFV strain NZ2 appeared more potent compared to strain D1701 with respect to both its antiviral and antifibrotic activity on the basis of dosages estimated by titration of active virus. These results show a potential therapeutic approach against two important human liver pathogens HBV and HCV that independently addresses concomitant liver fibrosis. Further studies are required to characterize the details of the mechanisms involved in this novel therapeutic principle.

  7. Characterization of acute rat parvovirus infection by in situ hybridization.

    PubMed

    Gaertner, D J; Jacoby, R O; Johnson, E A; Paturzo, F X; Smith, A L; Brandsma, J L

    1993-04-01

    In situ hybridization and virus titration were used to characterize early stages of rat virus (RV) infection of rat pups after oronasal inoculation. Results suggest that virus enters through the lung and that early viremia leads rapidly to pantropic infection. Cells derived from all three germ layers were infected with RV, but those of endodermal and mesodermal origin were the predominant targets. Infection of vascular endothelium was widespread and was associated with hemorrhage and infarction in the brain. Convalescence from acute infection was accompanied by mononuclear cell infiltrates at sites containing RV DNA. Viral DNA was also detected in endothelium, fibroblasts and smooth muscle myofibers four weeks after inoculation. Further examination of these cells as potential sites of persistent infection is warranted.

  8. Seoul virus infection in a Wisconsin patient with recent travel to China, March 2009: first documented case in the Midwestern United States.

    PubMed

    Nielsen, Carrie F; Sethi, Vishal; Petroll, Andrew E; Kazmierczak, James; Erickson, Bobbie R; Nichol, Stuart T; Rollin, Pierre E; Davis, Jeffrey P

    2010-12-01

    Diagnosis of Seoul virus-associated hemorrhagic fever with renal syndrome (HFRS) cases among United States residents is rare. We describe confirmation of a Seoul virus infection in a 36-year-old scientist who worked with laboratory rats in Milwaukee, Wisconsin, but most likely acquired the infection during a trip to Shenyang, China.

  9. Equine Arteritis Virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    03. Nidovirales : 03.004. Arteriviridae : 03.004.0. {03.004.0. unknown} : 03.004.0.01. Arterivirus : 03.004.0.01.001. Equine arteritis virus will be published online. The article details the phenotypic and genotypic makeup of equine arteritis virus (EAV), and summarizes its biological properties....

  10. Virus separation using membranes.

    PubMed

    Grein, Tanja A; Michalsky, Ronald; Czermak, Peter

    2014-01-01

    Industrial manufacturing of cell culture-derived viruses or virus-like particles for gene therapy or vaccine production are complex multistep processes. In addition to the bioreactor, such processes require a multitude of downstream unit operations for product separation, concentration, or purification. Similarly, before a biopharmaceutical product can enter the market, removal or inactivation of potential viral contamination has to be demonstrated. Given the complexity of biological solutions and the high standards on composition and purity of biopharmaceuticals, downstream processing is the bottleneck in many biotechnological production trains. Membrane-based filtration can be an economically attractive and efficient technology for virus separation. Viral clearance, for instance, of up to seven orders of magnitude has been reported for state of the art polymeric membranes under best conditions.This chapter summarizes the fundamentals of virus ultrafiltration, diafiltration, or purification with adsorptive membranes. In lieu of an impractical universally applicable protocol for virus filtration, application of these principles is demonstrated with two examples. The chapter provides detailed methods for production, concentration, purification, and removal of a rod-shaped baculovirus (Autographa californica M nucleopolyhedrovirus, about 40 × 300 nm in size, a potential vector for gene therapy, and an industrially important protein expression system) or a spherical parvovirus (minute virus of mice, 22-26 nm in size, a model virus for virus clearance validation studies).

  11. Papaya Ringspot Virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The term papaya ringspot virus (PRSV) was coined by Jensen in 1949, to describe a papaya disease in Hawaii. Later work showed that diseases such as papaya mosaic and watermelon mosaic virus-1 were caused by PRSV. The primary host range of PRSV is papaya and cucurbits, with Chenopium amaranticolor ...

  12. Positive reinforcement for viruses

    PubMed Central

    Vigant, Frederic; Jung, Michael; Lee, Benhur

    2010-01-01

    Summary Virus-cell membrane fusion requires a critical transition from positive to negative membrane curvature. St. Vincent et al., in PNAS (St Vincent, et al., 2010), designed a class of antivirals that targets this transition. These Rigid Amphipathic Fusion Inhibitors are active against an array of enveloped viruses. PMID:21035726

  13. Positive reinforcement for viruses.

    PubMed

    Vigant, Frederic; Jung, Michael; Lee, Benhur

    2010-10-29

    Virus-cell membrane fusion requires a critical transition from positive to negative membrane curvature. St. Vincent et al. (2010), in PNAS, designed a class of antivirals that targets this transition. These rigid amphipathic fusion inhibitors are active against an array of enveloped viruses.

  14. Rift Valley Fever Virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rift Valley fever virus (RVFV) is a mosquito-transmitted virus or arbovirus that is endemic in sub-Saharan Africa. In the last decade, Rift Valley fever (RVF) outbreaks have resulted in loss of human and animal life, as well as had significant economic impact. The disease in livestock is primarily a...

  15. Papaya ringspot virus (Potyviridae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Papaya ringspot virus, a member of the family Potyviridae, is single stranded RNA plant virus with a monocistronic genome of about 10,326 nucleotides that is expressed via a large polyprotein subsequently cleaved into functional proteins. It causes severe damage on cucurbit crops such as squash and...

  16. Zika Virus Disease.

    PubMed

    Slenczka, Werner

    2016-06-01

    The history of Zika virus disease serves as a paradigm of a typical emerging viral infection. Zika virus disease, a mosquito-borne flavivirus, was first isolated in 1947 in the Zika forest of Uganda. The same virus was also isolated from jungle-dwelling mosquitoes (Aedes [Stegomyia] africanus). In many areas of Africa and South Asia human infections with Zika virus were detected by both serology and virus isolation. About 80% of infections are asymptomatic, and in 20% a mostly mild disease with fever, rash, arthralgia, and conjunctivitis may occur. Fetal infections with malformations were not recorded in Africa or Asia. Zika virus was imported to northern Brazil possibly during the world soccer championship that was hosted by Brazil in June through July 2014. A cluster of severe fetal malformations with microcephaly and ocular defects was noted in 2015 in the northeast of Brazil, and intrauterine infections with Zika virus were confirmed. The dramatic change in Zika virus pathogenicity upon its introduction to Brazil has remained an enigma.

  17. Zika Virus and Pregnancy.

    PubMed

    Stagg, Denise; Hurst, Helen M

    2016-01-01

    Recent outbreaks of Zika virus and reports linking infection in pregnant women with microcephaly in newborns have caused concern worldwide. Information has been evolving rapidly. Nurses and other clinicians, especially those who work with women of childbearing age, play a pivotal role in disseminating accurate information and identifying potential cases of Zika virus infection.

  18. Zika Virus and Pregnancy.

    PubMed

    Stagg, Denise; Hurst, Helen M

    2016-01-01

    Recent outbreaks of Zika virus and reports linking infection in pregnant women with microcephaly in newborns have caused concern worldwide. Information has been evolving rapidly. Nurses and other clinicians, especially those who work with women of childbearing age, play a pivotal role in disseminating accurate information and identifying potential cases of Zika virus infection. PMID:27287356

  19. Zika Virus Disease.

    PubMed

    Slenczka, Werner

    2016-06-01

    The history of Zika virus disease serves as a paradigm of a typical emerging viral infection. Zika virus disease, a mosquito-borne flavivirus, was first isolated in 1947 in the Zika forest of Uganda. The same virus was also isolated from jungle-dwelling mosquitoes (Aedes [Stegomyia] africanus). In many areas of Africa and South Asia human infections with Zika virus were detected by both serology and virus isolation. About 80% of infections are asymptomatic, and in 20% a mostly mild disease with fever, rash, arthralgia, and conjunctivitis may occur. Fetal infections with malformations were not recorded in Africa or Asia. Zika virus was imported to northern Brazil possibly during the world soccer championship that was hosted by Brazil in June through July 2014. A cluster of severe fetal malformations with microcephaly and ocular defects was noted in 2015 in the northeast of Brazil, and intrauterine infections with Zika virus were confirmed. The dramatic change in Zika virus pathogenicity upon its introduction to Brazil has remained an enigma. PMID:27337468

  20. Rats! Oh No, Not Rats!

    ERIC Educational Resources Information Center

    Strong, Gary E.

    1987-01-01

    Examples of problems encountered in a new library building--including rats and humidity--and a description of the library's collections provide a framework for this presentation of the California State Library's emergency management planning. Current preservation efforts are documented and the library's disaster and security plans are described.…

  1. Transgenic hepatocarcinogenesis in the rat.

    PubMed Central

    Hully, J. R.; Su, Y.; Lohse, J. K.; Griep, A. E.; Sattler, C. A.; Haas, M. J.; Dragan, Y.; Peterson, J.; Neveu, M.; Pitot, H. C.

    1994-01-01

    Although transgenic hepatocarcinogenesis has been accomplished in the mouse with a number of genetic constructs targeting the oncogene to expression primarily in the liver, no example of this process has yet been developed in the rat. Because our understanding of the multistage nature of hepatocarcinogenesis is most advanced in the rat, we have developed a strain of transgenic rats carrying the promoter-enhancer sequences of the mouse albumin gene linked 5' to the simian virus-40 T antigen gene. A line of transgenic rats bearing this transgene has been developed from a single founder female. Five to six copies of the transgene, possibly in tandem, occur within the genome of the transgenic animals, which are maintained by heterozygous matings. Livers of transgenic animals are histologically normal after weaning; at 2 months of age, small foci of vacuolated cells appear in this organ. By 4 months of age, all animals exhibit focal lesions and nodules consisting primarily of small basophilic cells, many of which exhibit considerable cytoplasmic vacuolization. Mating of animals each bearing the transgene results in rats with a demyelinating condition that develops acutely in pregnant females and more chronically in males. Ultrastructural studies of these cells indicate that the vacuoles contain substantial amounts of glycogen, with the cells resembling hepatoblasts. Malignant neoplasms with both a glandular and a hepatoblastoma/hepatocellular carcinoma pattern arise from the nodules. Enzyme and immunohistochemical studies of all lesions reveal many similarities in gene expression to comparable lesions in rats subjected to chemically induced hepatocarcinogenesis, with certain exceptions. The placental form of glutathione-S-transferase is absent from all lesions in the transgenic animal, as is the expression of connexin 32. A significant number of lesions express serum albumin, and many, but not all, exhibit the T antigen. Lesions expressing the T antigen also contain

  2. Influenza A virus reassortment.

    PubMed

    Steel, John; Lowen, Anice C

    2014-01-01

    Reassortment is the process by which influenza viruses swap gene segments. This genetic exchange is possible due to the segmented nature of the viral genome and occurs when two differing influenza viruses co-infect a cell. The viral diversity generated through reassortment is vast and plays an important role in the evolution of influenza viruses. Herein we review recent insights into the contribution of reassortment to the natural history and epidemiology of influenza A viruses, gained through population scale phylogenic analyses. We describe methods currently used to study reassortment in the laboratory, and we summarize recent progress made using these experimental approaches to further our understanding of influenza virus reassortment and the contexts in which it occurs.

  3. Respiratory viruses and children.

    PubMed

    Heikkinen, Terho

    2016-07-01

    Respiratory viruses place a great disease burden especially on the youngest children in terms of high rates of infection, bacterial complications and hospitalizations. In developing countries, some viral infections are even associated with substantial mortality in children. The interaction between viruses and bacteria is probably much more common and clinically significant than previously understood. Respiratory viruses frequently initiate the cascade of events that ultimately leads to bacterial infection. Effective antiviral agents can substantially shorten the duration of the viral illness and prevent the development of bacterial complications. Viral vaccines have the potential to not only prevent the viral infection but also decrease the incidence of bacterial complications. At present, antivirals and vaccines are only available against influenza viruses, but new vaccines and antivirals against other viruses, especially for RSV, are being developed. PMID:27177731

  4. Respiratory viruses and children.

    PubMed

    Heikkinen, Terho

    2016-07-01

    Respiratory viruses place a great disease burden especially on the youngest children in terms of high rates of infection, bacterial complications and hospitalizations. In developing countries, some viral infections are even associated with substantial mortality in children. The interaction between viruses and bacteria is probably much more common and clinically significant than previously understood. Respiratory viruses frequently initiate the cascade of events that ultimately leads to bacterial infection. Effective antiviral agents can substantially shorten the duration of the viral illness and prevent the development of bacterial complications. Viral vaccines have the potential to not only prevent the viral infection but also decrease the incidence of bacterial complications. At present, antivirals and vaccines are only available against influenza viruses, but new vaccines and antivirals against other viruses, especially for RSV, are being developed.

  5. Akabane virus infection.

    PubMed

    Kirkland, P D

    2015-08-01

    Akabane virus is a Culicoides-borne orthobunyavirus that is teratogenic to the fetus of cattle and small ruminant species. Depending upon the stage of gestation atwhich infection occurs, and the length of gestation of the mammalian host, a range of congenital defects may be observed. The developing central nervous system is usually the most severely affected, with hydranencephaly and arthrogryposis most frequently observed. Less commonly, some strains of Akabane virus can cause encephalitis in the neonate or, rarely, adult cattle. Akabane viruses are known to be widespread in temperate and tropical regions of Australia, Southeast Asia, the Middle East and some African countries. Disease is infrequently observed in regions where this virus is endemic and the presence of the virus remains unrecognised in the absence of serological surveillance. In some Asian countries, vaccines are used to minimise the occurrence of disease. PMID:26601444

  6. Infectious Viral Quantification of Chikungunya Virus-Virus Plaque Assay.

    PubMed

    Kaur, Parveen; Lee, Regina Ching Hua; Chu, Justin Jang Hann

    2016-01-01

    The plaque assay is an essential method for quantification of infectious virus titer. Cells infected with virus particles are overlaid with a viscous substrate. A suitable incubation period results in the formation of plaques, which can be fixed and stained for visualization. Here, we describe a method for measuring Chikungunya virus (CHIKV) titers via virus plaque assays.

  7. Virus discovery and recent insights into virus diversity in arthropods.

    PubMed

    Junglen, Sandra; Drosten, Christian

    2013-08-01

    Recent studies on virus discovery have focused mainly on mammalian and avian viruses. Arbovirology with its long tradition of ecologically oriented investigation is now catching up, with important novel insights into the diversity of arthropod-associated viruses. Recent discoveries include taxonomically outlying viruses within the families Flaviviridae, Togaviridae, and Bunyaviridae, and even novel virus families within the order Nidovirales. However, the current focusing of studies on blood-feeding arthropods has restricted the range of arthropod hosts analyzed for viruses so far. Future investigations should include species from other arthropod taxa than Ixodita, Culicidae and Phlebotominae in order to shed light on the true diversity of arthropod viruses.

  8. Tumor necrosis factor amplifies measles virus-mediated Ia induction on astrocytes.

    PubMed Central

    Massa, P T; Schimpl, A; Wecker, E; ter Meulen, V

    1987-01-01

    We describe the induction of Ia on cultured astrocytes by measles virus and the amplification of this induction by tumor necrosis factor (TNF). Measles virus induces Ia on rat astrocytes by direct interaction with these cells. TNF does not induce significant levels of Ia at any dose from 1 to 10,000 units/ml. As little as 10 units of TNF per ml, however, amplifies Ia-inducing signals generated by measles virus in astrocytes. In contrast, TNF and measles virus induce class I major histocompatibility complex (MHC) antigens, when applied individually, and TNF amplification of measles virus class I MHC induction is not apparent. The induction of either Ia or class I MHC antigens on rat astrocytes by measles virus does not depend on glial-derived soluble factors generated during infection. Since brain cells are normally lacking MHC antigens upon which T cells depend for interaction with antigen presenting cells, these data indicate that the ability of measles virus to directly stimulate MHC antigen expression and the ability of TNF to amplify Ia expression locally in the brain may be important in initiating cell-mediated immune response to viral infection. PMID:3118363

  9. Realms of the Viruses Online

    ERIC Educational Resources Information Center

    Liu, Dennis

    2007-01-01

    Viruses have evolved strategies for infecting all taxa, but most viruses are highly specific about their cellular host. In humans, viruses cause diverse diseases, from chronic but benign warts, to acute and deadly hemorrhagic fever. Viruses have entertaining names like Zucchini Yellow Mosaic, Semliki Forest, Coxsackie, and the original terminator,…

  10. Tembusu Virus in Ducks, China

    PubMed Central

    Cao, Zhenzhen; Zhang, Cun; Liu, Yuehuan; Ye, Weicheng; Han, Jingwen; Ma, Guoming; Zhang, Dongdong; Xu, Feng; Gao, Xuhui; Tang, Yi; Shi, Shaohua; Wan, Chunhe; Zhang, Chen; He, Bin; Yang, Mengjie; Lu, Xinhao; Huang, Yu; Diao, Youxiang; Ma, Xuejun

    2011-01-01

    In China in 2010, a disease outbreak in egg-laying ducks was associated with a flavivirus. The virus was isolated and partially sequenced. The isolate exhibited 87%–91% identity with strains of Tembusu virus, a mosquito-borne flavivirus of the Ntaya virus group. These findings demonstrate emergence of Tembusu virus in ducks. PMID:22000358

  11. Postmortem Stability of Ebola Virus

    PubMed Central

    Prescott, Joseph; Bushmaker, Trenton; Fischer, Robert; Miazgowicz, Kerri; Judson, Seth

    2015-01-01

    The ongoing Ebola virus outbreak in West Africa has highlighted questions regarding stability of the virus and detection of RNA from corpses. We used Ebola virus–infected macaques to model humans who died of Ebola virus disease. Viable virus was isolated <7 days posteuthanasia; viral RNA was detectable for 10 weeks. PMID:25897646

  12. Virus-PEDOT Biocomposite Films

    PubMed Central

    Donavan, Keith C.; Arter, Jessica A.

    2012-01-01

    Virus-poly(3,4-ethylenedioxythiophene) (virus-PEDOT) biocomposite films are prepared by electropolymerizing 3,4-ethylenedioxythiophene (EDOT) in aqueous electrolytes containing 12 mM LiClO4 and the bacteriophage M13. The concentration of virus in these solutions, [virus]soln, is varied from 3 nM to 15 nM. A quartz crystal microbalance is used to directly measure the total mass of the biocomposite film during its electrodeposition. In combination with a measurement of the electrodeposition charge, the mass of the virus incorporated into the film is calculated. These data show that concentration of the M13 within the electropolymerized film, [virus]film, increases linearly with [virus]soln. The incorporation of virus particles into the PEDOT film from solution is efficient, resulting in a concentration ratio: [virus]film:[virus]soln ≈450. Virus incorporation into the PEDOT causes roughening of the film topography that is observed using scanning electron microscopy and atomic force microscopy (AFM). The electrical conductivity of the virus-PEDOT film, measured perpendicular to the plane of the film using conductive tip AFM, decreases linearly with virus loading, from 270 μS/cm for pure PE-DOT films to 50 μS/cm for films containing 100 μM virus. The presence on the virus surface of displayed affinity peptides did not significantly influence the efficiency of incorporation into virus-PEDOT biocomposite films. PMID:22856875

  13. A Virus in Turbo Pascal.

    ERIC Educational Resources Information Center

    Teleky, Heidi Ann; And Others

    1993-01-01

    Addresses why the authors feel it is not inappropriate to teach about viruses in the how-to, hands-on fashion. Identifies the special features of Turbo Pascal that have to be used for the creation of an effective virus. Defines virus, derives its structure, and from this structure is derived the implemented virus. (PR)

  14. Computer Viruses: Pathology and Detection.

    ERIC Educational Resources Information Center

    Maxwell, John R.; Lamon, William E.

    1992-01-01

    Explains how computer viruses were originally created, how a computer can become infected by a virus, how viruses operate, symptoms that indicate a computer is infected, how to detect and remove viruses, and how to prevent a reinfection. A sidebar lists eight antivirus resources. (four references) (LRW)

  15. Chimpanzee/human mAbs to vaccinia virus B5 protein neutralize vaccinia and smallpox viruses and protect mice against vaccinia virus.

    PubMed

    Chen, Zhaochun; Earl, Patricia; Americo, Jeffrey; Damon, Inger; Smith, Scott K; Zhou, Yi-Hua; Yu, Fujuan; Sebrell, Andrew; Emerson, Suzanne; Cohen, Gary; Eisenberg, Roselyn J; Svitel, Juraj; Schuck, Peter; Satterfield, William; Moss, Bernard; Purcell, Robert

    2006-02-01

    Chimpanzee Fabs against the B5 envelope glycoprotein of vaccinia virus were isolated and converted into complete mAbs with human gamma 1 heavy chain constant regions. The two mAbs (8AH8AL and 8AH7AL) displayed high binding affinities to B5 (Kd of 0.2 and 0.7 nM). The mAb 8AH8AL inhibited the spread of vaccinia virus as well as variola virus (the causative agent of smallpox) in vitro, protected mice from subsequent intranasal challenge with virulent vaccinia virus, protected mice when administered 2 days after challenge, and provided significantly greater protection than that afforded by a previously isolated rat anti-B5 mAb (19C2) or by vaccinia immune globulin. The mAb bound to a conformational epitope between amino acids 20 and 130 of B5. These chimpanzee/human anti-B5 mAbs may be useful in the prevention and treatment of vaccinia virus-induced complications of vaccination against smallpox and may also be effective in the immunoprophylaxis and immunotherapy of smallpox.

  16. Dual Role of Herpes Simplex Virus 1 pUS9 in Virus Anterograde Axonal Transport and Final Assembly in Growth Cones in Distal Axons

    PubMed Central

    Boadle, Ross A.

    2015-01-01

    ABSTRACT The herpes simplex virus type 1 (HSV-1) envelope protein pUS9 plays an important role in virus anterograde axonal transport and spread from neuronal axons. In this study, we used both confocal microscopy and transmission electron microscopy (TEM) to examine the role of pUS9 in the anterograde transport and assembly of HSV-1 in the distal axon of human and rat dorsal root ganglion (DRG) neurons using US9 deletion (US9−), repair (US9R), and wild-type (strain F, 17, and KOS) viruses. Using confocal microscopy and single and trichamber culture systems, we observed a reduction but not complete block in the anterograde axonal transport of capsids to distal axons as well as a marked (∼90%) reduction in virus spread from axons to Vero cells with the US9 deletion viruses. Axonal transport of glycoproteins (gC, gD, and gE) was unaffected. Using TEM, there was a marked reduction or absence of enveloped capsids, in varicosities and growth cones, in KOS strain and US9 deletion viruses, respectively. Capsids (40 to 75%) in varicosities and growth cones infected with strain 17, F, and US9 repair viruses were fully enveloped compared to less than 5% of capsids found in distal axons infected with the KOS strain virus (which also lacks pUS9) and still lower (<2%) with the US9 deletion viruses. Hence, there was a secondary defect in virus assembly in distal axons in the absence of pUS9 despite the presence of key envelope proteins. Overall, our study supports a dual role for pUS9, first in anterograde axonal transport and second in virus assembly in growth cones in distal axons. IMPORTANCE HSV-1 has evolved mechanisms for its efficient transport along sensory axons and subsequent spread from axons to epithelial cells after reactivation. In this study, we show that deletion of the envelope protein pUS9 leads to defects in virus transport along axons (partial defect) and in virus assembly and egress from growth cones (marked defect). Virus assembly and exit in the neuronal

  17. Viruses of Chelonia.

    PubMed

    Ahne, W

    1993-02-01

    Viruses occurring in turtles and tortoises are hetergeneous but according to ecologic characteristics and pathogenic properties they can be divided in two major groups: 1. Arboviruses (toga-, flavi-, rhabdo- and bunyaviruses) transmitted by arthropods cause severe diseases in homoiothermic vertebrates. The viruses are of great epidemiological interest in human and veterinary medicine. Chelonia and other reptiles infected by bites of vectors e.g. Aedes, Anopheles, Culex develop cyclic viremia without injury. The ectothermic animals maintain inapparent arbovirus infections during hibernation and they play role as reservoirs for these viruses. 2. Viruses of Chelonia origin (papova-, herpes-, irido- and paramyxoviruses) associated with diseases of infected turtles and tortoises have been described frequently during the last 20 years. Several viruses or virus-like particles could be demonstrated in affected reptiles mainly by electron microscopy. Especially herpesviruses seem to attack Chelonia and epizootics due to infections with these viruses were reported in several reptiles in collections. However, the etiological role of the agents detected is not well documented yet. PMID:8456570

  18. Ocular Tropism of Respiratory Viruses

    PubMed Central

    Rota, Paul A.; Tumpey, Terrence M.

    2013-01-01

    SUMMARY Respiratory viruses (including adenovirus, influenza virus, respiratory syncytial virus, coronavirus, and rhinovirus) cause a broad spectrum of disease in humans, ranging from mild influenza-like symptoms to acute respiratory failure. While species D adenoviruses and subtype H7 influenza viruses are known to possess an ocular tropism, documented human ocular disease has been reported following infection with all principal respiratory viruses. In this review, we describe the anatomical proximity and cellular receptor distribution between ocular and respiratory tissues. All major respiratory viruses and their association with human ocular disease are discussed. Research utilizing in vitro and in vivo models to study the ability of respiratory viruses to use the eye as a portal of entry as well as a primary site of virus replication is highlighted. Identification of shared receptor-binding preferences, host responses, and laboratory modeling protocols among these viruses provides a needed bridge between clinical and laboratory studies of virus tropism. PMID:23471620

  19. Rats, cities, people, and pathogens: a systematic review and narrative synthesis of literature regarding the ecology of rat-associated zoonoses in urban centers.

    PubMed

    Himsworth, Chelsea G; Parsons, Kirbee L; Jardine, Claire; Patrick, David M

    2013-06-01

    Urban Norway and black rats (Rattus norvegicus and Rattus rattus) are the source of a number of pathogens responsible for significant human morbidity and mortality in cities around the world. These pathogens include zoonotic bacteria (Leptospira interrogans, Yersina pestis, Rickettsia typhi, Bartonella spp., Streptobacillus moniliformis), viruses (Seoul hantavirus), and parasites (Angiostrongylus cantonensis). A more complete understanding of the ecology of these pathogens in people and rats is critical for determining the public health risks associated with urban rats and for developing strategies to monitor and mitigate those risks. Although the ecology of rat-associated zoonoses is complex, due to the multiple ways in which rats, people, pathogens, vectors, and the environment may interact, common determinants of human disease can still be identified. This review summarizes the ecology of zoonoses associated with urban rats with a view to identifying similarities, critical differences, and avenues for further study.

  20. THE PROTECTIVE ACTION OF TRYPAN RED AGAINST INFECTION BY A NEUROTROPIC VIRUS

    PubMed Central

    Wood, Harland G.; Rusoff, Irving I.

    1945-01-01

    Trypan red, when injected intraperitoneally into mice, has been found greatly to lower the incidence of the infection of mice inoculated intraperitoneally with the neurotropic MM virus. The protective action of the dye is overcome if the virus is inoculated in too high concentration. The lowered incidence of infection was observed in mice inoculated with virus for as long as 29 days after the last dye injection. Of a number of dyes tested, trypan red, brilliant vital red, and Congo red were found effective. In cotton rats inoculated intraperitoneally with MM virus, trypan red was likewise found to lower the incidence of infection. With monkeys and a typical poliomyelitis virus no protection was observed against the virus inoculated intraperitoneally. The latter experiment is considered to have been inadequate for a critical test of the effect of trypan red on poliomyelitis infection. When either the MM virus or Lansing virus were inoculated intracerebrally into mice, the effect of the dye on incidence of infection was small. In the case of the Lansing virus the difference was statistically significant, however. The possible relation of alteration in the permeability of the barrier between the blood and the central nervous system as a cause of the effect of trypan red is discussed. PMID:19871501

  1. Genome of horsepox virus.

    PubMed

    Tulman, E R; Delhon, G; Afonso, C L; Lu, Z; Zsak, L; Sandybaev, N T; Kerembekova, U Z; Zaitsev, V L; Kutish, G F; Rock, D L

    2006-09-01

    Here we present the genomic sequence of horsepox virus (HSPV) isolate MNR-76, an orthopoxvirus (OPV) isolated in 1976 from diseased Mongolian horses. The 212-kbp genome contained 7.5-kbp inverted terminal repeats and lacked extensive terminal tandem repetition. HSPV contained 236 open reading frames (ORFs) with similarity to those in other OPVs, with those in the central 100-kbp region most conserved relative to other OPVs. Phylogenetic analysis of the conserved region indicated that HSPV is closely related to sequenced isolates of vaccinia virus (VACV) and rabbitpox virus, clearly grouping together these VACV-like viruses. Fifty-four HSPV ORFs likely represented fragments of 25 orthologous OPV genes, including in the central region the only known fragmented form of an OPV ribonucleotide reductase large subunit gene. In terminal genomic regions, HSPV lacked full-length homologues of genes variably fragmented in other VACV-like viruses but was unique in fragmentation of the homologue of VACV strain Copenhagen B6R, a gene intact in other known VACV-like viruses. Notably, HSPV contained in terminal genomic regions 17 kbp of OPV-like sequence absent in known VACV-like viruses, including fragments of genes intact in other OPVs and approximately 1.4 kb of sequence present only in cowpox virus (CPXV). HSPV also contained seven full-length genes fragmented or missing in other VACV-like viruses, including intact homologues of the CPXV strain GRI-90 D2L/I4R CrmB and D13L CD30-like tumor necrosis factor receptors, D3L/I3R and C1L ankyrin repeat proteins, B19R kelch-like protein, D7L BTB/POZ domain protein, and B22R variola virus B22R-like protein. These results indicated that HSPV contains unique genomic features likely contributing to a unique virulence/host range phenotype. They also indicated that while closely related to known VACV-like viruses, HSPV contains additional, potentially ancestral sequences absent in other VACV-like viruses.

  2. Viruses in reptiles

    PubMed Central

    2011-01-01

    The etiology of reptilian viral diseases can be attributed to a wide range of viruses occurring across different genera and families. Thirty to forty years ago, studies of viruses in reptiles focused mainly on the zoonotic potential of arboviruses in reptiles and much effort went into surveys and challenge trials of a range of reptiles with eastern and western equine encephalitis as well as Japanese encephalitis viruses. In the past decade, outbreaks of infection with West Nile virus in human populations and in farmed alligators in the USA has seen the research emphasis placed on the issue of reptiles, particularly crocodiles and alligators, being susceptible to, and reservoirs for, this serious zoonotic disease. Although there are many recognised reptilian viruses, the evidence for those being primary pathogens is relatively limited. Transmission studies establishing pathogenicity and cofactors are likewise scarce, possibly due to the relatively low commercial importance of reptiles, difficulties with the availability of animals and permits for statistically sound experiments, difficulties with housing of reptiles in an experimental setting or the inability to propagate some viruses in cell culture to sufficient titres for transmission studies. Viruses as causes of direct loss of threatened species, such as the chelonid fibropapilloma associated herpesvirus and ranaviruses in farmed and wild tortoises and turtles, have re-focused attention back to the characterisation of the viruses as well as diagnosis and pathogenesis in the host itself. 1. Introduction 2. Methods for working with reptilian viruses 3. Reptilian viruses described by virus families 3.1. Herpesviridae 3.2. Iridoviridae 3.2.1 Ranavirus 3.2.2 Erythrocytic virus 3.2.3 Iridovirus 3.3. Poxviridae 3.4. Adenoviridae 3.5. Papillomaviridae 3.6. Parvoviridae 3.7. Reoviridae 3.8. Retroviridae and inclusion body disease of Boid snakes 3.9. Arboviruses 3.9.1. Flaviviridae 3.9.2. Togaviridae 3.10. Caliciviridae

  3. [Ebola virus disease].

    PubMed

    Nazimek, Katarzyna; Bociaga-Jasik, Monika; Bryniarski, Krzysztof; Gałas, Aleksander; Garlicki, Aleksander; Gawda, Anna; Gawlik, Grzegorz; Gil, Krzysztof; Kosz-Vnenchak, Magdalena; Mrozek-Budzyn, Dorota; Olszanecki, Rafał; Piatek, Anna; Zawilińska, Barbara; Marcinkiewicz, Janusz

    2014-01-01

    Ebola is one of the most virulent zoonotic RNA viruses causing in humans haemorrhagic fever with fatality ratio reaching 90%. During the outbreak of 2014 the number of deaths exceeded 8.000. The "imported" cases reported in Western Europe and USA highlighted the extreme risk of Ebola virus spreading outside the African countries. Thus, haemorrhagic fever outbreak is an international epidemiological problem, also due to the lack of approved prevention and therapeutic strategies. The editorial review article briefly summarizes current knowledge on Ebola virus disease epidemiology, etiology, pathogenesis, clinical presentation, diagnosis as well as possible prevention and treatment.

  4. Antibodies to Tacaribe Serocomplex Viruses (Family Arenaviridae, Genus Arenavirus) in Cricetid Rodents from New Mexico, Texas, and Mexico

    PubMed Central

    Milazzo, Mary L.; Barragán-Gomez, Artemio; Hanson, John Delton; Estrada-Franco, Jose G.; Arellano, Elizabeth; González-Cózatl, Francisco X.; Fernández-Salas, Ildefonso; Ramirez-Aguilar, Francisco; Rogers, Duke S.; Bradley, Robert D.

    2010-01-01

    Abstract Blood samples from 4893 cricetid rodents were tested for antibody (immunoglobulin G) to Whitewater Arroyo virus and Amaparí virus to extend our knowledge of the natural host range and geographical distribution of Tacaribe serocomplex viruses in North America. Antibodies to arenaviruses were found in northern pygmy mice (Baiomys taylori), woodrats (Neotoma spp.), northern grasshopper mice (Onychomys leucogaster), oryzomys (Oryzomys spp.), deermice (Megadontomys nelsoni and Peromyscus spp.), harvest mice (Reithrodontomys spp.), and cotton rats (Sigmodon spp.) captured in New Mexico, Texas, or Mexico. Comparison of endpoint antibody titers to Whitewater Arroyo virus and Amaparí virus in individual blood samples indicated that the Tacaribe complex viruses enzootic in Texas and Mexico are antigenically diverse. PMID:20795917

  5. Hepatitis B virus (image)

    MedlinePlus

    Hepatitis B is also known as serum hepatitis and is spread through blood and sexual contact. It is ... population. This photograph is an electronmicroscopic image of hepatitis B virus particles. (Image courtesy of the Centers for ...

  6. [Zika, a neurotropic virus?].

    PubMed

    Del Carpio-Orantes, Luis

    2016-01-01

    In this paper, the neurotropism potential Zika virus is discussed, by comparison with viruses both RNA and DNA are neurotropic known, also it is said that compared with the new viruses that have affected the Americas, as the chikungunya, Zika has shown great affinity by brain tissue, manifested by a high incidence of acute neurological conditions, such as Guillain-Barré syndrome, among others, as well as the reported incidence of microcephaly that is abnormally high compared with the previous incidence, which, in a stillborn subject necropsied significant alterations demonstrated in brain tissue, identifying viral material and live virus in the fetoplacental complex, and demonstrating the impact both white matter and gray matter as well as basal ganglia, corpus callosum, ventricles and spinal cord, which could explain the microcephaly that concerns him. Although not a direct cause-effect relationship is demonstrated, however current evidence supports that relationship, hoping to be supported scientifically.

  7. The dengue viruses.

    PubMed Central

    Henchal, E A; Putnak, J R

    1990-01-01

    Dengue, a major public health problem throughout subtropical and tropical regions, is an acute infectious disease characterized by biphasic fever, headache, pain in various parts of the body, prostration, rash, lymphadenopathy, and leukopenia. In more severe or complicated dengue, patients present with a severe febrile illness characterized by abnormalities of hemostasis and increased vascular permeability, which in some instances results in a hypovolemic shock. Four distinct serotypes of the dengue virus (dengue-1, dengue-2, dengue-3, and dengue-4) exist, with numerous virus strains found worldwide. Molecular cloning methods have led to a greater understanding of the structure of the RNA genome and definition of virus-specific structural and nonstructural proteins. Progress towards producing safe, effective dengue virus vaccines, a goal for over 45 years, has been made. Images PMID:2224837

  8. VIRUS instrument enclosures

    NASA Astrophysics Data System (ADS)

    Prochaska, T.; Allen, R.; Mondrik, N.; Rheault, J. P.; Sauseda, M.; Boster, E.; James, M.; Rodriguez-Patino, M.; Torres, G.; Ham, J.; Cook, E.; Baker, D.; DePoy, Darren L.; Marshall, Jennifer L.; Hill, G. J.; Perry, D.; Savage, R. D.; Good, J. M.; Vattiat, Brian L.

    2014-08-01

    The Visible Integral-Field Replicable Unit Spectrograph (VIRUS) instrument will be installed at the Hobby-Eberly Telescope† in the near future. The instrument will be housed in two enclosures that are mounted adjacent to the telescope, via the VIRUS Support Structure (VSS). We have designed the enclosures to support and protect the instrument, to enable servicing of the instrument, and to cool the instrument appropriately while not adversely affecting the dome environment. The system uses simple HVAC air handling techniques in conjunction with thermoelectric and standard glycol heat exchangers to provide efficient heat removal. The enclosures also provide power and data transfer to and from each VIRUS unit, liquid nitrogen cooling to the detectors, and environmental monitoring of the instrument and dome environments. In this paper, we describe the design and fabrication of the VIRUS enclosures and their subsystems.

  9. Respiratory syncytial virus (RSV)

    MedlinePlus

    ... RSV often spreads quickly in crowded households and day care centers. The virus can live for a half ... The following increase the risk for RSV: Attending day care Being near tobacco smoke Having school-aged brothers ...

  10. West Nile Virus

    MedlinePlus

    ... to human beings through their bites. Credit: CDC Biology, Genetics, & Clinical Research NIAID conducts and funds basic and clinical research on WNV biology and viral structure, ways the virus causes human ...

  11. What's West Nile Virus?

    MedlinePlus

    ... is caused by a bite from an infected mosquito that's already carrying the virus, but it's important ... the risk of being bitten by an infected mosquito is greatest from July to early September. But ...

  12. Avoiding Computer Viruses.

    ERIC Educational Resources Information Center

    Rowe, Joyce; And Others

    1989-01-01

    The threat of computer sabotage is a real concern to business teachers and others responsible for academic computer facilities. Teachers can minimize the possibility. Eight suggestions for avoiding computer viruses are given. (JOW)

  13. West Nile Virus

    MedlinePlus

    ... appeared in the United States in 1999. Infected mosquitoes spread the virus that causes it. People who ... barrels Stay indoors between dusk and dawn, when mosquitoes are most active Use screens on windows to ...

  14. The dengue viruses.

    PubMed

    Henchal, E A; Putnak, J R

    1990-10-01

    Dengue, a major public health problem throughout subtropical and tropical regions, is an acute infectious disease characterized by biphasic fever, headache, pain in various parts of the body, prostration, rash, lymphadenopathy, and leukopenia. In more severe or complicated dengue, patients present with a severe febrile illness characterized by abnormalities of hemostasis and increased vascular permeability, which in some instances results in a hypovolemic shock. Four distinct serotypes of the dengue virus (dengue-1, dengue-2, dengue-3, and dengue-4) exist, with numerous virus strains found worldwide. Molecular cloning methods have led to a greater understanding of the structure of the RNA genome and definition of virus-specific structural and nonstructural proteins. Progress towards producing safe, effective dengue virus vaccines, a goal for over 45 years, has been made. PMID:2224837

  15. Viruses and Multiple Sclerosis

    PubMed Central

    Virtanen, Jussi Oskari; Jacobson, Steve

    2016-01-01

    Multiple sclerosis (MS) is a heterogeneous disease that develops as an interplay between the immune system and environmental stimuli in genetically susceptible individuals. There is increasing evidence that viruses may play a role in MS pathogenesis acting as these environmental triggers. However, it is not known if any single virus is causal, or rather several viruses can act as triggers in disease development. Here, we review the association of different viruses to MS with an emphasis on two herpesviruses, Epstein-Barr virus (EBV) and human herpesvirus 6 (HHV-6). These two agents have generated the most impact during recent years as possible co-factors in MS disease development. The strongest argument for association of EBV with MS comes from the link between symptomatic infectious mononucleosis and MS and from seroepidemiological studies. In contrast to EBV, HHV-6 has been found significantly more often in MS plaques than in MS normal appearing white matter or non-MS brains and HHV-6 re-activation has been reported during MS clinical relapses. In this review we also suggest new strategies, including the development of new infectious animal models of MS and antiviral MS clinical trials, to elucidate roles of different viruses in the pathogenesis of this disease. Furthermore, we introduce the idea of using unbiased sequence-independent pathogen discovery methodologies, such as next generation sequencing, to study MS brain tissue or body fluids for detection of known viral sequences or potential novel viral agents. PMID:22583435

  16. Human Influenza Virus Infections.

    PubMed

    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. PMID:27486731

  17. Virus templated metallic nanoparticles

    NASA Astrophysics Data System (ADS)

    Aljabali, Alaa A. A.; Barclay, J. Elaine; Lomonossoff, George P.; Evans, David J.

    2010-12-01

    Plant viruses are considered as nanobuilding blocks that can be used as synthons or templates for novel materials. Cowpea mosaic virus (CPMV) particles have been shown to template the fabrication of metallic nanoparticles by an electroless deposition metallization process. Palladium ions were electrostatically bound to the virus capsid and, when reduced, acted as nucleation sites for the subsequent metal deposition from solution. The method, although simple, produced highly monodisperse metallic nanoparticles with a diameter of ca. <=35 nm. CPMV-templated particles were prepared with cobalt, nickel, iron, platinum, cobalt-platinum and nickel-iron.Plant viruses are considered as nanobuilding blocks that can be used as synthons or templates for novel materials. Cowpea mosaic virus (CPMV) particles have been shown to template the fabrication of metallic nanoparticles by an electroless deposition metallization process. Palladium ions were electrostatically bound to the virus capsid and, when reduced, acted as nucleation sites for the subsequent metal deposition from solution. The method, although simple, produced highly monodisperse metallic nanoparticles with a diameter of ca. <=35 nm. CPMV-templated particles were prepared with cobalt, nickel, iron, platinum, cobalt-platinum and nickel-iron. Electronic supplementary information (ESI) available: Additional experimental detail, agarose gel electrophoresis results, energy dispersive X-ray spectra, ζ-potential measurements, dynamic light scattering data, nanoparticle tracking analysis and an atomic force microscopy image of Ni-CPMV. See DOI: 10.1039/c0nr00525h

  18. Human Influenza Virus Infections.

    PubMed

    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.

  19. Transmission of influenza A viruses.

    PubMed

    Neumann, Gabriele; Kawaoka, Yoshihiro

    2015-05-01

    Influenza A viruses cause respiratory infections that range from asymptomatic to deadly in humans. Widespread outbreaks (pandemics) are attributable to 'novel' viruses that possess a viral hemagglutinin (HA) gene to which humans lack immunity. After a pandemic, these novel viruses form stable virus lineages in humans and circulate until they are replaced by other novel viruses. The factors and mechanisms that facilitate virus transmission among hosts and the establishment of novel lineages are not completely understood, but the HA and basic polymerase 2 (PB2) proteins are thought to play essential roles in these processes by enabling avian influenza viruses to infect mammals and replicate efficiently in their new host. Here, we summarize our current knowledge of the contributions of HA, PB2, and other viral components to virus transmission and the formation of new virus lineages. PMID:25812763

  20. Transmission of Influenza A Viruses

    PubMed Central

    Neumann, Gabriele; Kawaoka, Yoshihiro

    2015-01-01

    Influenza A viruses cause respiratory infections that range from asymptomatic to deadly in humans. Widespread outbreaks (pandemics) are attributable to ‘novel’ viruses that possess a viral hemagglutinin (HA) gene to which humans lack immunity. After a pandemic, these novel viruses form stable virus lineages in humans and circulate until they are replaced by other novel viruses. The factors and mechanisms that facilitate virus transmission among hosts and the establishment of novel lineages are not completely understood, but the HA and basic polymerase 2 (PB2) proteins are thought to play essential roles in these processes by enabling avian influenza viruses to infect mammals and replicate efficiently in their new host. Here, we summarize our current knowledge of the contributions of HA, PB2, and other viral components to virus transmission and the formation of new virus lineages. PMID:25812763

  1. Smaller Fleas: Viruses of Microorganisms

    PubMed Central

    Hyman, Paul; Abedon, Stephen T.

    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 Bacteria (bacteriophages), the viruses of domain Archaea (archaeal viruses), the viruses of protists, the viruses of microscopic fungi such as yeasts (mycoviruses), and even the viruses of other viruses (satellite viruses). In this paper we provide an introduction to the concept of viruses of microorganisms, a.k.a., viruses of microbes. We provide broad discussion particularly of VoM diversity. VoM diversity currently spans, in total, at least three-dozen virus families. This is roughly ten families per category—bacterial, archaeal, fungal, and protist—with some virus families infecting more than one of these microorganism major taxa. Such estimations, however, will vary with further discovery and taxon assignment and also are dependent upon what forms of life one includes among microorganisms. PMID:24278736

  2. Smaller fleas: viruses of microorganisms.

    PubMed

    Hyman, Paul; Abedon, Stephen T

    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 Bacteria (bacteriophages), the viruses of domain Archaea (archaeal viruses), the viruses of protists, the viruses of microscopic fungi such as yeasts (mycoviruses), and even the viruses of other viruses (satellite viruses). In this paper we provide an introduction to the concept of viruses of microorganisms, a.k.a., viruses of microbes. We provide broad discussion particularly of VoM diversity. VoM diversity currently spans, in total, at least three-dozen virus families. This is roughly ten families per category-bacterial, archaeal, fungal, and protist-with some virus families infecting more than one of these microorganism major taxa. Such estimations, however, will vary with further discovery and taxon assignment and also are dependent upon what forms of life one includes among microorganisms.

  3. In vitro infectivity assay for mouse mammary tumor virus.

    PubMed

    Vacquier, J P; Cardiff, R D

    1979-08-01

    Studies of mouse mammary tumor virus (MMTV) have been impeded by the lack of an in vitro infectivity assay. We have developed a rapid, quantitative in vitro assay for MMTV infectivity based on the detection of positively staining foci by immunoperoxidase. This assay and a 50% end-point titration of MMTV infectivity gave identical virus titers. Infection of a rat hepatoma cell line, a feline kidney cell line, and a normal murine mammary gland cell line by virus from the mouse mammary tumor GR3A cell line was linear with respect to virus concentration. The infectious titers obtained in both homologous and heterologous cell lines were not significantly different, demonstrating a lack of host range specificity. Virus infectivity was inactivated by heating at 55 degrees C and by ultraviolet irradiation. Rabbit anti-MMTV serum neutralized the infectivity with a 50% neutralization end point of 1:5000. Applications of this assay to the study of the immunological, biological, and biochemical characteristics of MMTV are discussed.

  4. Changes in mumps virus neurovirulence phenotype associated with quasispecies heterogeneity

    SciTech Connect

    Sauder, Christian J. . E-mail: rubins@cber.fda.gov

    2006-06-20

    Mumps virus is a highly neurotropic virus with evidence of central nervous system invasion (CNS) in approximately half of all cases of infection. In countries where live attenuated mumps virus vaccines were introduced, the number of mumps cases declined dramatically; however, recently, the safety of some vaccine strains has been questioned. For example, one of the most widely used vaccines, the Urabe AM9 strain, was causally associated with meningitis, leading to the withdrawal of this product from the market in several countries. This highlights the need for a better understanding of the attenuation process and the identification of markers of attenuation. To this end, we further attenuated the Urabe AM9 strain by serial passage in cell culture and compared the complete nucleotide sequences of the parental and passaged viruses. Interestingly, despite a dramatic decrease in virus virulence (as assayed in rats), the only genomic changes were in the form of changes in the level of genetic heterogeneity at specific genome sites, i.e., either selection of one nucleotide variant at positions where the starting material exhibited nucleotide heterogeneity or the evolution of an additional nucleotide to create a heterogenic site. This finding suggests that changes in the level of genetic heterogeneity at specific genome sites can have profound neurovirulence phenotypic consequences and, therefore, caution should be exercised when evaluating genetic markers of virulence or attenuation based only on a consensus sequence.

  5. Virus-like particle-based countermeasures against Rift Valley fever virus.

    PubMed

    Koukuntla, R; Mandell, R B; Flick, R

    2012-09-01

    Rift Valley fever virus (RVFV) is an arbovirus that causes significant morbidity and mortality in both humans and livestock. With increased world travel and the threat of bioterrorism, there is a real risk of RVFV spreading to naïve geographical areas (Trans. R. Soc. Trop. Med. Hyg., 73, 1979, 618; MMWR Morb. Mortal. Wkly Rep., 49, 2000, 905). The introduction of RVFV would cause critical public health, agricultural and economic damage. Despite the clear need for an efficacious vaccine, there are no United States (US) Food and Drug Administration or US Department of Agriculture approved vaccines against RVFV. To address this need, a virus-like particle (VLP)-based vaccine candidate was developed. First, a non-replicating chimeric RVF VLP vaccine candidate was generated that protected mice and rats against a lethal RVFV challenge. This was followed by the development and optimization of conditions for production of RVF VLPs in insect and mammalian cells. Immunological studies demonstrated that VLP-based vaccine candidates elicit both humoral and cellular immune responses. Subsequent challenge studies using a lethal wild-type RVFV strain under high-containment conditions showed that RVF VLP vaccine candidates can completely protect mice and rats. PMID:22958258

  6. [Zika virus infection during pregnancy].

    PubMed

    Picone, O; Vauloup-Fellous, C; D'Ortenzio, E; Huissoud, C; Carles, G; Benachi, A; Faye, A; Luton, D; Paty, M-C; Ayoubi, J-M; Yazdanpanah, Y; Mandelbrot, L; Matheron, S

    2016-05-01

    A Zika virus epidemic is currently ongoing in the Americas. This virus is linked to congenital infections with potential severe neurodevelopmental dysfunction. However, incidence of fetal infection and whether this virus is responsible of other fetal complications are still unknown. National and international public health authorities recommend caution and several prevention measures. Declaration of Zika virus infection is now mandatory in France. Given the available knowledge on Zika virus, we suggest here a review of the current recommendations for management of pregnancy in case of suspicious or infection by Zika virus in a pregnant woman. PMID:27079865

  7. [Zika virus infection during pregnancy].

    PubMed

    Picone, O; Vauloup-Fellous, C; D'Ortenzio, E; Huissoud, C; Carles, G; Benachi, A; Faye, A; Luton, D; Paty, M-C; Ayoubi, J-M; Yazdanpanah, Y; Mandelbrot, L; Matheron, S

    2016-05-01

    A Zika virus epidemic is currently ongoing in the Americas. This virus is linked to congenital infections with potential severe neurodevelopmental dysfunction. However, incidence of fetal infection and whether this virus is responsible of other fetal complications are still unknown. National and international public health authorities recommend caution and several prevention measures. Declaration of Zika virus infection is now mandatory in France. Given the available knowledge on Zika virus, we suggest here a review of the current recommendations for management of pregnancy in case of suspicious or infection by Zika virus in a pregnant woman.

  8. Interactions between endogenous baboon type-C virus and oncogenic viruses. I. Syncytium induction and development of infectivity assay.

    PubMed

    Ahmed, M; Korol, W; Larson, D L; Harewood, K R; Mayyasi, S A

    1975-11-15

    Cells releasing the endogenous baboon virus (BV) can interact with human KC cells containing the Rous sarcoma virus (RSV) genome, resulting in cell fusion and syncytium formation. This interaction has been utilized in the development of a sensitive infectivity assay for BV. The titration pattern is of a one-hit type, demonstrating a linear relationship between virus concentration and number of syncytial plaques obtained in the KC co-cultivation assay. Endpoint titration comparisons indicate that the KC test is as sensitive as the immunofluorescence or the RNA-directed DNA-polymerase assays. Attempts to develop an XC test for BV failed, indicating that while BV can interact with the RSV genome it will do so in the human KC cells and not in the rat XC cells. Syncytia are also induced when KC cells are directly exposed to cell-free BV; however, a linear dose relationship is not obtained. When syncytium-positive KC cultures are passaged, the syncytia disappear and a chronic BV infection is established. These KC-BV cells then lose the ability to interact with either the endogenous cat RD-114 virus or the Mason-Pfizer virus which are known to form syncytia with KC cells.

  9. Characterization of a novel rat cytomegalovirus (RCMV) infecting placenta-uterus of Rattus rattus diardii.

    PubMed

    Loh, H S; Mohd-Azmi, M L; Lai, K Y; Sheikh-Omar, A R; Zamri-Saad, M

    2003-12-01

    A new rat cytomegalovirus (RCMV) isolated from the placenta/uterus of a house rat (Rattus rattus diardii) was found to productively infect rat embryo fibroblast (REF) cells. The virus produced typical herpesvirus-like cytopathic effects characterized by a lytic infection. The well-known herpesvirus morphology was confirmed by electron microscopy. Its slow growth in cell culture indicated that the virus is belonging to subfamily Betaherpesvirinae. Electron microscopy techniques and immunohistochemistry confirmed the presence of herpesviral inclusion bodies and virus related particles in the cytoplasm and nucleus of infected cells. Hyperimmune serum against the Maastricht strain of RCMV revealed the virus identity in neutralization test, immunoperoxidase and immunofluorescence techniques. Despite typical characteristics of CMV, the viral genome is significantly different from that of Maastricht, English, UPM/Sg and UPM/Kn strains. The dissimilarities, which have not been reported before, had been confirmed by mean of restriction endonuclease analysis. The new RCMV strain, a virus that infects placenta and uterus of rats, has been named as ALL-03.

  10. Rift Valley fever virus: a seroepidemiologic study of small terrestrial vertebrates in South Africa.

    PubMed

    Pretorius, A; Oelofsen, M J; Smith, M S; van der Ryst, E

    1997-12-01

    Epizootics of Rift Valley fever (RVF) are often associated with periods of heavy rainfall, which are favorable for mosquito vectors. However, in seasons with normal or low rainfall, enzootic circulation occurs, suggesting the existence of a natural host that can act as a cryptic carrier during interepizootic periods. To confirm the role of heavy rainfall in epizootic circulation, and to identify a possible natural host of RVF virus, serum samples from small terrestrial mammals in the Free State and Northern Cape regions of South Africa were collected before and after the 1988 floods. These areas are known to support epizootic circulation of RVF virus. The samples were tested for the presence of RVF virus-specific IgG using an ELISA and positive sera were confirmed by a neutralization test. Forty-seven (15%) of 312 Aethomys namaquensis (Namaqua rock rat) had antibodies to RVF virus. Of these positive sera, nine (6%) of 141 were collected before the floods of 1988 and 38 (22%) of 171 were collected afterwards (P = 0.001). Naive A. namaquensis were inoculated with RVF virus and developed a viremia, but no clinical symptoms, suggesting that they can act as temporary asymptomatic carriers of the virus. These results suggest a role for A. namaquensis as a cryptic carrier for RVF virus during interepizootic periods and support the results of other studies suggesting an amplifying role for heavy rainfall in the circulation of RVF virus. PMID:9430529

  11. The haemagglutinin protein is an important determinant of measles virus tropism for dendritic cells in vitro.

    PubMed

    Ohgimoto, S; Ohgimoto, K; Niewiesk, S; Klagge, I M; Pfeuffer, J; Johnston, I C; Schneider-Schaulies, J; Weidmann, A; ter Meulen, V; Schneider-Schaulies, S

    2001-08-01

    Recombinant measles viruses (MV) in which the authentic glycoprotein genes encoding the fusion and the haemagglutinin (H) proteins of the Edmonston (ED) vaccine strains were swapped singly or doubly for the corresponding genes of a lymphotropic MV wild-type virus (strain WTF) were used previously to investigate MV tropism in cell lines in tissue culture. When these recombinants and their parental strains, the molecular ED-based clone (ED-tag) and WTF, were used to infect cotton rats, only viruses expressing the MV WTF H protein replicated in secondary lymphatic tissues and caused significant immunosuppression. In vitro, viruses containing the ED H protein revealed a tropism for human peripheral blood lymphocytes as documented by enhanced binding and virus production, whereas those containing the WTF H protein replicated well in monocyte-derived dendritic cells (Mo-DC). This did not correlate with more efficient binding of these viruses to DC, but with an enhancement of uptake, virus spread, accumulation of viral antigens and virus production. Thus, replacement of the ED H protein with WTF H protein was sufficient to confer the DC tropism of WTF to ED-tag in vitro. This study suggests that the MV H protein plays an important role in determining cell tropism to immune cells and this may play an important role in the induction of immunosuppression in vivo. PMID:11457989

  12. Recombinant Vaccinia Virus: Immunization against Multiple Pathogens

    NASA Astrophysics Data System (ADS)

    Perkus, Marion E.; Piccini, Antonia; Lipinskas, Bernard R.; Paoletti, Enzo

    1985-09-01

    The coding sequences for the hepatitis B virus surface antigen, the herpes simplex virus glycoprotein D, and the influenza virus hemagglutinin were inserted into a single vaccinia virus genome. Rabbits inoculated intravenously or intradermally with this polyvalent vaccinia virus recombinant produced antibodies reactive to all three authentic foreign antigens. In addition, the feasibility of multiple rounds of vaccination with recombinant vaccinia virus was demonstrated.

  13. Two African viruses serologically and morphologically related to rabies virus.

    PubMed

    Shope, R E; Murphy, F A; Harrison, A K; Causey, O R; Kemp, G E; Simpson, D I; Moore, D L

    1970-11-01

    Lagos bat virus and an isolate from shrews (IbAn 27377), both from Nigeria, were found to be bullet-shaped and to mature intracytoplasmically in association with a distinct matrix. They were related to, but readily distinguishable from, rabies virus and each other by complement fixation and neutralization tests. The three viruses, including rabies, form a subgrouping within the rhabdoviruses. PMID:5530013

  14. [Viruses and civilization].

    PubMed

    Chastel, C

    1999-01-01

    A few million years ago, when primates moved from the east African forest to the savannah, they were already infected with endogenous viruses and occultly transmitted them to the prime Homo species. However it was much later with the building of the first large cities in Mesopotamia that interhuman viral transmission began in earnest. Spreading was further enhanced with the organization of the Egyptian, Greek, Roman, and Arab empires around the Mediterranean. Discovery of the New World in 1492 led to an unprecedented clash of civilizations and the destruction of pre-Columbian Indian civilizations. It also led to a rapid spread of viruses across the Atlantic Ocean with the emergence of yellow fever and appearance of smallpox and measles throughout the world. However the greatest opportunities for worldwide viral development have been created by our present, modern civilization. This fact is illustrated by epidemic outbreaks of human immunodeficiency virus, Venezuela hemorrhagic fever, Rift valley fever virus, and monkey pox virus. Close analysis underscores the major role of human intervention in producing these events.

  15. Viruses and Multiple Sclerosis

    PubMed Central

    Owens, Gregory P.; Gilden, Don; Burgoon, Mark P.; Yu, Xiaoli; Bennett, Jeffrey L.

    2012-01-01

    Multiple sclerosis (MS) is a chronic demyelinating disorder of unknown etiology, possibly caused by a virus or virus-triggered immunopathology. The virus might reactivate after years of latency and lyse oligodendrocytes, as in progressive multifocal leukoencephalopathy, or initiate immunopathological demyelination, as in animals infected with Theiler’s murine encephalomyelitis virus or coronaviruses. The argument for a viral cause of MS is supported by epidemiological analyses and studies of MS in identical twins, indicating that disease is acquired. However, the most important evidence is the presence of bands of oligoclonal IgG (OCBs) in MS brain and CSF that persist throughout the lifetime of the patient. OCBs are found almost exclusively in infectious CNS disorders, and antigenic targets of OCBs represent the agent that causes disease. Here, the authors review past attempts to identify an infectious agent in MS brain cells and discuss the promise of using recombinant antibodies generated from clonally expanded plasma cells in brain and CSF to identify disease-relevant antigens. They show how this strategy has been used successfully to analyze antigen specificity in subacute sclerosing panencephalitis, a chronic encephalitis caused by measles virus, and in neuromyelitis optica, a chronic autoimmune demyelinating disease produced by antibodies directed against the aquaporin-4 water channel. PMID:22130640

  16. Viruses and multiple sclerosis.

    PubMed

    Owens, Gregory P; Gilden, Don; Burgoon, Mark P; Yu, Xiaoli; Bennett, Jeffrey L

    2011-12-01

    Multiple sclerosis (MS) is a chronic demyelinating disorder of unknown etiology, possibly caused by a virus or virus-triggered immunopathology. The virus might reactivate after years of latency and lyse oligodendrocytes, as in progressive multifocal leukoencephalopathy, or initiate immunopathological demyelination, as in animals infected with Theiler's murine encephalomyelitis virus or coronaviruses. The argument for a viral cause of MS is supported by epidemiological analyses and studies of MS in identical twins, indicating that disease is acquired. However, the most important evidence is the presence of bands of oligoclonal IgG (OCBs) in MS brain and CSF that persist throughout the lifetime of the patient. OCBs are found almost exclusively in infectious CNS disorders, and antigenic targets of OCBs represent the agent that causes disease. Here, the authors review past attempts to identify an infectious agent in MS brain cells and discuss the promise of using recombinant antibodies generated from clonally expanded plasma cells in brain and CSF to identify disease-relevant antigens. They show how this strategy has been used successfully to analyze antigen specificity in subacute sclerosing panencephalitis, a chronic encephalitis caused by measles virus, and in neuromyelitis optica, a chronic autoimmune demyelinating disease produced by antibodies directed against the aquaporin-4 water channel. PMID:22130640

  17. Attenuation of Vaccinia Virus.

    PubMed

    Yakubitskiy, S N; Kolosova, I V; Maksyutov, R A; Shchelkunov, S N

    2015-01-01

    Since 1980, in the post-smallpox vaccination era the human population has become increasingly susceptible compared to a generation ago to not only the variola (smallpox) virus, but also other zoonotic orthopoxviruses. The need for safer vaccines against orthopoxviruses is even greater now. The Lister vaccine strain (LIVP) of vaccinia virus was used as a parental virus for generating a recombinant 1421ABJCN clone defective in five virulence genes encoding hemagglutinin (A56R), the IFN-γ-binding protein (B8R), thymidine kinase (J2R), the complement-binding protein (C3L), and the Bcl-2-like inhibitor of apoptosis (N1L). We found that disruption of these loci does not affect replication in mammalian cell cultures. The isogenic recombinant strain 1421ABJCN exhibits a reduced inflammatory response and attenuated neurovirulence relative to LIVP. Virus titers of 1421ABJCN were 3 lg lower versus the parent VACV LIVP when administered by the intracerebral route in new-born mice. In a subcutaneous mouse model, 1421ABJCN displayed levels of VACV-neutralizing antibodies comparable to those of LIVP and conferred protective immunity against lethal challenge by the ectromelia virus. The VACV mutant holds promise as a safe live vaccine strain for preventing smallpox and other orthopoxvirus infections. PMID:26798498

  18. [Markers of hepatitis virus].

    PubMed

    Suzuki, Fumitaka

    2008-11-01

    Hepatitis B virus (HBV) and hepatitis C virus (HCV) are the major viruses known to cause viral hepatitis. Serological markers are commonly used as diagnostic and/or prognostic indicators of acute or chronic HBV or HCV infection. The ability to detect HBV DNA in serum has been reported to have prognostic value for the outcome of chronic HBV infection. A rapid and sustained drop in HBV DNA or HCV RNA levels in patients under therapy has been shown to be a predictive factor for a favourable treatment outcome. Various techniques for detecting HBV DNA or HCV RNA have already been described; however, there are various problems with the sensitivity or detection range of those methods. New virus measuring methods have recently been reported and used. The Cobas Taq Man HCV Test is a new method to detect HBV DNA and HCV RNA with higher sensitivity and a broader range of quantitation than conventional methods. Some reports have shown that these methods improve therapy monitoring and the management of HBV or HCV infection. Moreover, hepatitis E virus (HEV) infection has been reported in Japan. The clinical features and viral markers of HEV have also been described. PMID:19086457

  19. Special Issue: Honey Bee Viruses.

    PubMed

    Gisder, Sebastian; Genersch, Elke

    2015-10-01

    Pollination of flowering plants is an important ecosystem service provided by wild insect pollinators and managed honey bees. Hence, losses and declines of pollinating insect species threaten human food security and are of major concern not only for apiculture or agriculture but for human society in general. Honey bee colony losses and bumblebee declines have attracted intensive research interest over the last decade and although the problem is far from being solved we now know that viruses are among the key players of many of these bee losses and bumblebee declines. With this special issue on bee viruses we, therefore, aimed to collect high quality original papers reflecting the current state of bee virus research. To this end, we focused on newly discovered viruses (Lake Sinai viruses, bee macula-like virus), or a so far neglected virus species (Apis mellifera filamentous virus), and cutting edge technologies (mass spectrometry, RNAi approach) applied in the field.

  20. Chlorella viruses isolated in China

    SciTech Connect

    Zhang, Y.; Burbank, D.E.; Van Etten, J.L. )

    1988-09-01

    Plaque-forming viruses of the unicellular, eukaryotic, exsymbiotic, Chlorella-like green algae strain NC64A, which are common in the United States, were also present in fresh water collected in the People's Republic of China. Seven of the Chinese viruses were examined in detail and compared with the Chlorella viruses previously isolated in the United States. Like the American viruses, the Chinese viruses were large polyhedra and sensitive to chloroform. They contained numerous structural proteins and large double-stranded DNA genomes of at least 300 kilobase pairs. Each of the DNAs from the Chinese viruses contained 5-methyldeoxycytosine, which varied from 12.6 to 46.7% of the deoxycytosine, and N{sup 6}-methyldeoxyadenosine, which varied from 2.2 to 28.3% of the deoxyadenosine. Four of the Chinese virus DNAs hybridized extensively with {sup 32}P-labeled DNA from the American virus PBCV-1, and three hybridized poorly.

  1. Special Issue: Honey Bee Viruses

    PubMed Central

    Gisder, Sebastian; Genersch, Elke

    2015-01-01

    Pollination of flowering plants is an important ecosystem service provided by wild insect pollinators and managed honey bees. Hence, losses and declines of pollinating insect species threaten human food security and are of major concern not only for apiculture or agriculture but for human society in general. Honey bee colony losses and bumblebee declines have attracted intensive research interest over the last decade and although the problem is far from being solved we now know that viruses are among the key players of many of these bee losses and bumblebee declines. With this special issue on bee viruses we, therefore, aimed to collect high quality original papers reflecting the current state of bee virus research. To this end, we focused on newly discovered viruses (Lake Sinai viruses, bee macula-like virus), or a so far neglected virus species (Apis mellifera filamentous virus), and cutting edge technologies (mass spectrometry, RNAi approach) applied in the field. PMID:26702462

  2. Testing for Human Immunodeficiency Virus

    MedlinePlus

    ... incisions made in the mother’s abdomen and uterus. Human Immunodeficiency Virus (HIV): A virus that attacks certain cells of the body’s immune system and causes acquired immunodeficiency syndrome (AIDS). Immune System: ...

  3. Emerging issues in virus taxonomy.

    PubMed

    van Regenmortel, Marc H V; Mahy, Brian W J

    2004-01-01

    Viruses occupy a unique position in biology. Although they possess some of the properties of living systems such as having a genome, they are actually nonliving infectious entities and should not be considered microorganisms. A clear distinction should be drawn between the terms virus, virion, and virus species. Species is the most fundamental taxonomic category used in all biological classification. In 1991, the International Committee on Taxonomy of Viruses (ICTV) decided that the category of virus species should be used in virus classification together with the categories of genus and family. More than 50 ICTV study groups were given the task of demarcating the 1,550 viral species that were recognized in the 7th ICTV report, which was published in 2000. We briefly describe the changes in virus classification that were introduced in that report. We also discuss recent proposals to introduce a nonlatinized binomial nomenclature for virus species. PMID:15078590

  4. Special Issue: Honey Bee Viruses.

    PubMed

    Gisder, Sebastian; Genersch, Elke

    2015-10-01

    Pollination of flowering plants is an important ecosystem service provided by wild insect pollinators and managed honey bees. Hence, losses and declines of pollinating insect species threaten human food security and are of major concern not only for apiculture or agriculture but for human society in general. Honey bee colony losses and bumblebee declines have attracted intensive research interest over the last decade and although the problem is far from being solved we now know that viruses are among the key players of many of these bee losses and bumblebee declines. With this special issue on bee viruses we, therefore, aimed to collect high quality original papers reflecting the current state of bee virus research. To this end, we focused on newly discovered viruses (Lake Sinai viruses, bee macula-like virus), or a so far neglected virus species (Apis mellifera filamentous virus), and cutting edge technologies (mass spectrometry, RNAi approach) applied in the field. PMID:26702462

  5. Ebola (Ebola Virus Disease): Prevention

    MedlinePlus

    ... Search The CDC Cancel Submit Search The CDC Ebola (Ebola Virus Disease) Note: Javascript is disabled or is ... message, please visit this page: About CDC.gov . Ebola (Ebola Virus Disease) About Ebola Questions & Answers 2014 ...

  6. Ebola (Ebola Virus Disease): Transmission

    MedlinePlus

    ... Search The CDC Cancel Submit Search The CDC Ebola (Ebola Virus Disease) Note: Javascript is disabled or is ... message, please visit this page: About CDC.gov . Ebola (Ebola Virus Disease) About Ebola Questions & Answers 2014 ...

  7. Ebola (Ebola Virus Disease): Treatment

    MedlinePlus

    ... Search The CDC Cancel Submit Search The CDC Ebola (Ebola Virus Disease) Note: Javascript is disabled or is ... message, please visit this page: About CDC.gov . Ebola (Ebola Virus Disease) About Ebola Questions & Answers 2014 ...

  8. Ebola (Ebola Virus Disease): Diagnosis

    MedlinePlus

    ... Search The CDC Cancel Submit Search The CDC Ebola (Ebola Virus Disease) Note: Javascript is disabled or is ... message, please visit this page: About CDC.gov . Ebola (Ebola Virus Disease) About Ebola Questions & Answers 2014 ...

  9. Production of virus resistant plants

    DOEpatents

    Dougherty, W.G.; Lindbo, J.A.

    1996-12-10

    A method of suppressing virus gene expression in plants using untranslatable plus sense RNA is disclosed. The method is useful for the production of plants that are resistant to virus infection. 9 figs.

  10. Zika Virus Infection and Microcephaly.

    PubMed

    Millichap, J Gordon

    2016-01-01

    A Task Force established by the Brazil Ministry of Health investigated the possible association of microcephaly with Zika virus infection during pregnancy and a registry for microcephaly cases among women suspected to have had Zika virus infection during pregnancy.

  11. Chlorella viruses isolated in China.

    PubMed Central

    Zhang, Y P; Burbank, D E; Van Etten, J L

    1988-01-01

    Plaque-forming viruses of the unicellular, eucaryotic, exsymbiotic, Chlorella-like green algae strain NC64A, which are common in the United States, were also present in fresh water collected in the People's Republic of China. Seven of the Chinese viruses were examined in detail and compared with the Chlorella viruses previously isolated in the United States. Like the American viruses, the Chinese viruses were large polyhedra and sensitive to chloroform. They contained numerous structural proteins and large double-stranded DNA genomes of at least 300 kilobase pairs. Each of the DNAs from the Chinese viruses contained 5-methyldeoxycytosine, which varied from 12.6 to 46.7% of the deoxycytosine, and N6-methyldeoxyadenosine, which varied from 2.2 to 28.3% of the deoxyadenosine. Four of the Chinese virus DNAs hybridized extensively with DNA from the American virus PBCV-1, and three hybridized poorly. Images PMID:2847652

  12. 9 CFR 113.215 - Bovine Virus Diarrhea Vaccine, Killed Virus.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Bovine Virus Diarrhea Vaccine, Killed... REQUIREMENTS Killed Virus Vaccines § 113.215 Bovine Virus Diarrhea Vaccine, Killed Virus. Bovine Virus Diarrhea Vaccine, Killed Virus, shall be prepared from virus-bearing cell culture fluids. Only Master Seed...

  13. 9 CFR 113.215 - Bovine Virus Diarrhea Vaccine, Killed Virus.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Bovine Virus Diarrhea Vaccine, Killed... REQUIREMENTS Killed Virus Vaccines § 113.215 Bovine Virus Diarrhea Vaccine, Killed Virus. Bovine Virus Diarrhea Vaccine, Killed Virus, shall be prepared from virus-bearing cell culture fluids. Only Master Seed...

  14. 9 CFR 113.215 - Bovine Virus Diarrhea Vaccine, Killed Virus.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Bovine Virus Diarrhea Vaccine, Killed... REQUIREMENTS Killed Virus Vaccines § 113.215 Bovine Virus Diarrhea Vaccine, Killed Virus. Bovine Virus Diarrhea Vaccine, Killed Virus, shall be prepared from virus-bearing cell culture fluids. Only Master Seed...

  15. 9 CFR 113.215 - Bovine Virus Diarrhea Vaccine, Killed Virus.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Bovine Virus Diarrhea Vaccine, Killed... REQUIREMENTS Killed Virus Vaccines § 113.215 Bovine Virus Diarrhea Vaccine, Killed Virus. Bovine Virus Diarrhea Vaccine, Killed Virus, shall be prepared from virus-bearing cell culture fluids. Only Master Seed...

  16. Encephalomyocarditis virus infection in an Italian zoo

    PubMed Central

    2010-01-01

    A fatal Encephalomyocarditis virus (EMCV) infection epidemic involving fifteen primates occurred between October 2006 and February 2007 at the Natura Viva Zoo. This large open-field zoo park located near Lake Garda in Northern Italy hosts one thousand animals belonging to one hundred and fifty different species, including various lemur species. This lemur collection is the most relevant and rich in Italy. A second outbreak between September and November 2008 involved three lemurs. In all cases, the clinical signs were sudden deaths generally without any evident symptoms or only with mild unspecific clinical signs. Gross pathologic changes were characterized by myocarditis (diffuse or focal pallor of the myocardium), pulmonary congestion, emphysema, oedema and thoracic fluid. The EMCV was isolated and recognized as the causative agent of both outbreaks. The first outbreak in particular was associated with a rodent plague, confirming that rats are an important risk factor for the occurrence of the EMCV infection. PMID:20298561

  17. Encephalomyocarditis virus infection in an Italian zoo.

    PubMed

    Canelli, Elena; Luppi, Andrea; Lavazza, Antonio; Lelli, Davide; Sozzi, Enrica; Martin, Ana M Moreno; Gelmetti, Daniela; Pascotto, Ernesto; Sandri, Camillo; Magnone, William; Cordioli, Paolo

    2010-01-01

    A fatal Encephalomyocarditis virus (EMCV) infection epidemic involving fifteen primates occurred between October 2006 and February 2007 at the Natura Viva Zoo. This large open-field zoo park located near Lake Garda in Northern Italy hosts one thousand animals belonging to one hundred and fifty different species, including various lemur species. This lemur collection is the most relevant and rich in Italy. A second outbreak between September and November 2008 involved three lemurs. In all cases, the clinical signs were sudden deaths generally without any evident symptoms or only with mild unspecific clinical signs. Gross pathologic changes were characterized by myocarditis (diffuse or focal pallor of the myocardium), pulmonary congestion, emphysema, oedema and thoracic fluid. The EMCV was isolated and recognized as the causative agent of both outbreaks. The first outbreak in particular was associated with a rodent plague, confirming that rats are an important risk factor for the occurrence of the EMCV infection.

  18. RNA-Seq reveals virus-virus and virus-plant interactions in nature.

    PubMed

    Kamitani, Mari; Nagano, Atsushi J; Honjo, Mie N; Kudoh, Hiroshi

    2016-11-01

    As research on plant viruses has focused mainly on crop diseases, little is known about these viruses in natural environments. To understand the ecology of viruses in natural systems, comprehensive information on virus-virus and virus-host interactions is required. We applied RNA-Seq to plants from a natural population of Arabidopsis halleri subsp. gemmifera to simultaneously determine the presence/absence of all sequence-reported viruses, identify novel viruses and quantify the host transcriptome. By introducing the criteria of read number and genome coverage, we detected infections by Turnip mosaic virus (TuMV), Cucumber mosaic virus and Brassica yellows virus Active TuMV replication was observed by ultramicroscopy. De novo assembly further identified a novel partitivirus, Arabidopsis halleri partitivirus 1 Interestingly, virus reads reached a maximum level that was equivalent to that of the host's total mRNA, although asymptomatic infection was common. AhgAGO2, a key gene in host defence systems, was upregulated in TuMV-infected plants. Multiple infection was frequent in TuMV-infected leaves, suggesting that TuMV facilitates multiple infection, probably by suppressing host RNA silencing. Revealing hidden plant-virus interactions in nature can enhance our understanding of biological interactions and may have agricultural applications. PMID:27549115

  19. Dominant inhibitory Ras delays Sindbis virus-induced apoptosis in neuronal cells.

    PubMed Central

    Joe, A K; Ferrari, G; Jiang, H H; Liang, X H; Levine, B

    1996-01-01

    Mature neurons are more resistant than dividing cells or differentiating neurons to Sindbis virus-induced apoptotic death. Therefore, we hypothesized that mitogenic signal transduction pathways may influence susceptibility to Sindbis virus-induced apoptosis. Since Ras, a 21-kDa GTP-binding protein, plays an important role in cellular proliferation and neuronal differentiation, we investigated the effect of an inducible dominant inhibitory Ras on Sindbis virus-induced death of a rat pheochromocytoma cell line, PC12 cells. Dexamethasone induction of dominant inhibitory Ras (Ha Ras(Asn17)) expression in transfected PC12 cell lines (MMTV-M17-21 and GSrasDN6 cells) resulted in a marked delay in Sindbis virus-induced apoptosis, compared with infected, uninduced cells. The delay in death after Sindbis virus infection in induced versus uninduced PC12 cells was not associated with differences in viral titers or viral infectivity. No delay in Sindbis virus-induced apoptosis was observed in Ha Ras(Asn17)-transfected PC12 cells if dexamethasone induction was initiated less than 12 h before Sindbis virus infection or in wild-type PC12 cells infected with a chimeric Sindbis virus construct that expresses Ha Ras(Asn17). The delay in Sindbis virus-induced apoptosis in induced Ha Ras(Asn17)-transfected PC12 cells was associated with a decrease in cellular DNA synthesis as measured by 5'-bromo-2'-deoxyuridine incorporation. Thus, in PC12 cells, inducible dominant inhibitory Ras inhibits cellular proliferation and delays Sindbis virus-induced apoptosis. These findings suggest that a Ras-dependent signaling pathway is a determinant of neuronal susceptibility to Sindbis virus-induced apoptosis. PMID:8892895

  20. The cotton rat (Sigmodon hispidus) is a permissive small animal model of human metapneumovirus infection, pathogenesis, and protective immunity.

    PubMed

    Williams, John V; Tollefson, Sharon J; Johnson, Joyce E; Crowe, James E

    2005-09-01

    Human metapneumovirus (hMPV) is a newly described paramyxovirus that is an important cause of acute respiratory tract disease. We undertook to develop a small animal model of hMPV infection, pathogenesis, and protection. Hamsters, guinea pigs, cotton rats, and nine inbred strains of mice were inoculated intranasally with hMPV. The animals were sacrificed, and nasal and lung tissue virus yields were determined by plaque titration. None of the animals exhibited respiratory symptoms. The quantity of virus present in the nasal tissue ranged from 4.6 x 10(2) PFU/gram tissue (C3H mice) to greater than 10(5) PFU/gram (hamster). The amount of virus in the lungs was considerably less than in nasal tissue in each species tested, ranging from undetectable (<5 PFU/g; guinea pigs) to 1.8 x 10(5) PFU/gram (cotton rat). The peak virus titer in cotton rat lungs occurred on day 4 postinfection. hMPV-infected cotton rat lungs examined on day 4 postinfection exhibited histopathological changes consisting of peribronchial inflammatory infiltrates. Immunohistochemical staining detected virus only at the luminal surfaces of respiratory epithelial cells throughout the respiratory tract. hMPV-infected cotton rats mounted virus-neutralizing antibody responses and were partially protected against virus shedding and lung pathology on subsequent rechallenge with hMPV. Viral antigen was undetectable in the lungs on challenge of previously infected animals. This study demonstrates that the cotton rat is a permissive small animal model of hMPV infection that exhibits lung histopathology associated with infection and that primary infection protected animals against subsequent infection. This model will allow further in vivo studies of hMPV pathogenesis and evaluation of vaccine candidates.

  1. Deformed wing virus.

    PubMed

    de Miranda, Joachim R; Genersch, Elke

    2010-01-01

    Deformed wing virus (DWV; Iflaviridae) is one of many viruses infecting honeybees and one of the most heavily investigated due to its close association with honeybee colony collapse induced by Varroadestructor. In the absence of V.destructor DWV infection does not result in visible symptoms or any apparent negative impact on host fitness. However, for reasons that are still not fully understood, the transmission of DWV by V.destructor to the developing pupae causes clinical symptoms, including pupal death and adult bees emerging with deformed wings, a bloated, shortened abdomen and discolouration. These bees are not viable and die soon after emergence. In this review we will summarize the historical and recent data on DWV and its relatives, covering the genetics, pathobiology, and transmission of this important viral honeybee pathogen, and discuss these within the wider theoretical concepts relating to the genetic variability and population structure of RNA viruses, the evolution of virulence and the development of disease symptoms.

  2. Oncolytic viruses: finally delivering

    PubMed Central

    Seymour, Leonard W; Fisher, Kerry D

    2016-01-01

    Oncolytic viruses can be found at the confluence of virology, genetic engineering and pharmacology where versatile platforms for molecularly targeted anticancer agents can be designed and optimised. Oncolytic viruses offer several important advantages over traditional approaches, including the following. (1) Amplification of the active agent (infectious virus particles) within the tumour. This avoids unnecessary exposure to normal tissues experienced during delivery of traditional stoichiometric chemotherapy and maximises the therapeutic index. (2) The active cell-killing mechanisms, often independent of programmed death mechanisms, should decrease the emergence of acquired drug resistance. (3) Lytic death of cancer cells provides a pro-inflammatory microenvironment and the potential for induction of an anticancer vaccine response. (4) Tumour-selective expression and secretion of encoded anticancer biologics, providing a new realm of potent and cost-effective-targeted therapeutics. PMID:26766734

  3. Viruses and Asthma

    PubMed Central

    Dulek, Daniel E.; Peebles, R. Stokes

    2011-01-01

    Background Viral respiratory infection has long been known to influence the occurrence of asthma exacerbations. Over the last twenty years much effort has been put into clarifying the role that viral respiratory infections play in the eventual development of asthma. Scope of Review In this review we give a general background of the role of viruses in the processes of asthma exacerbation and asthma induction. We review recent additions to the literature in the last three years with particular focus on clinical and epidemiologic investigations of influenza, rhinovirus, bocavirus, respiratory syncytial virus, and metapneumovirus. Major Conclusions The development of asthma emerges from a complex interaction of genetic predisposition and environmental factors with viral infection likely playing a significant role in the effect of environment on asthma inception. General Significance Further understanding of the role that viruses play in asthma exacerbation and inception will contribute to decreased asthma morbidity in the future. PMID:21291960

  4. Complement-dependent cytotoxicity in rats bearing human adenovirus type 12-induced primary retinoblastoma-like tumor in the eye.

    PubMed

    Nishida, T; Mukai, N; Solish, S P

    1981-01-01

    Using an animal model of retinoblastoma in inbred rats and cultured human adenovirus type 12-induced retinoblastoma-like tumor cells (RAO 188), complement-dependent cytotoxicity was determined by measuring release of 3H-uridine labelled RNA. Sera from rats in which tumors did not grow after adenovirus type 12 inoculation had higher cytotoxicity against RAO 188 cells than sera from rats bearing primary adenovirus type 12-induced retinoblastoma-like tumor. These results showed that the rat which could raise antibodies against adenovirus type 12-induced retinoblastoma-like tumor cells did not allow the tumor growth in the eye after virus inoculation.

  5. Hendra virus and Nipah virus animal vaccines.

    PubMed

    Broder, Christopher C; Weir, Dawn L; Reid, Peter A

    2016-06-24

    Hendra virus (HeV) and Nipah virus (NiV) are zoonotic viruses that emerged in the mid to late 1990s causing disease outbreaks in livestock and people. HeV appeared in Queensland, Australia in 1994 causing a severe respiratory disease in horses along with a human case fatality. NiV emerged a few years later in Malaysia and Singapore in 1998-1999 causing a large outbreak of encephalitis with high mortality in people and also respiratory disease in pigs which served as amplifying hosts. The key pathological elements of HeV and NiV infection in several species of mammals, and also in people, are a severe systemic and often fatal neurologic and/or respiratory disease. In people, both HeV and NiV are also capable of causing relapsed encephalitis following recovery from an acute infection. The known reservoir hosts of HeV and NiV are several species of pteropid fruit bats. Spillovers of HeV into horses continue to occur in Australia and NiV has caused outbreaks in people in Bangladesh and India nearly annually since 2001, making HeV and NiV important transboundary biological threats. NiV in particular possesses several features that underscore its potential as a pandemic threat, including its ability to infect humans directly from natural reservoirs or indirectly from other susceptible animals, along with a capacity of limited human-to-human transmission. Several HeV and NiV animal challenge models have been developed which have facilitated an understanding of pathogenesis and allowed for the successful development of both active and passive immunization countermeasures.

  6. Hendra virus and Nipah virus animal vaccines.

    PubMed

    Broder, Christopher C; Weir, Dawn L; Reid, Peter A

    2016-06-24

    Hendra virus (HeV) and Nipah virus (NiV) are zoonotic viruses that emerged in the mid to late 1990s causing disease outbreaks in livestock and people. HeV appeared in Queensland, Australia in 1994 causing a severe respiratory disease in horses along with a human case fatality. NiV emerged a few years later in Malaysia and Singapore in 1998-1999 causing a large outbreak of encephalitis with high mortality in people and also respiratory disease in pigs which served as amplifying hosts. The key pathological elements of HeV and NiV infection in several species of mammals, and also in people, are a severe systemic and often fatal neurologic and/or respiratory disease. In people, both HeV and NiV are also capable of causing relapsed encephalitis following recovery from an acute infection. The known reservoir hosts of HeV and NiV are several species of pteropid fruit bats. Spillovers of HeV into horses continue to occur in Australia and NiV has caused outbreaks in people in Bangladesh and India nearly annually since 2001, making HeV and NiV important transboundary biological threats. NiV in particular possesses several features that underscore its potential as a pandemic threat, including its ability to infect humans directly from natural reservoirs or indirectly from other susceptible animals, along with a capacity of limited human-to-human transmission. Several HeV and NiV animal challenge models have been developed which have facilitated an understanding of pathogenesis and allowed for the successful development of both active and passive immunization countermeasures. PMID:27154393

  7. Protecting Your Computer from Viruses

    ERIC Educational Resources Information Center

    Descy, Don E.

    2006-01-01

    A computer virus is defined as a software program capable of reproducing itself and usually capable of causing great harm to files or other programs on the same computer. The existence of computer viruses--or the necessity of avoiding viruses--is part of using a computer. With the advent of the Internet, the door was opened wide for these…

  8. Avian influenza virus RNA extraction

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The efficient extraction and purification of viral RNA is critical for down-stream molecular applications whether it is the sensitive and specific detection of virus in clinical samples, virus gene cloning and expression, or quantification of avian influenza (AI) virus by molecular methods from expe...

  9. Ipomoviruses: Squash vein yellowing virus, Cucumber vein yellowing virus, Cassava brown streak virus, and Ugandan cassava brown streak virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ipomoviruses including Squash vein yellowing virus, Cucumber vein yellowing virus and Cassava brown streak virus are currently causing significant economic impact on crop production in several regions of the world. Only recently have results of detailed characterization of their whitefly transmissi...

  10. Computer Bytes, Viruses and Vaccines.

    ERIC Educational Resources Information Center

    Palmore, Teddy B.

    1989-01-01

    Presents a history of computer viruses, explains various types of viruses and how they affect software or computer operating systems, and describes examples of specific viruses. Available vaccines are explained, and precautions for protecting programs and disks are given. (nine references) (LRW)

  11. An introduction to computer viruses

    SciTech Connect

    Brown, D.R.

    1992-03-01

    This report on computer viruses is based upon a thesis written for the Master of Science degree in Computer Science from the University of Tennessee in December 1989 by David R. Brown. This thesis is entitled An Analysis of Computer Virus Construction, Proliferation, and Control and is available through the University of Tennessee Library. This paper contains an overview of the computer virus arena that can help the reader to evaluate the threat that computer viruses pose. The extent of this threat can only be determined by evaluating many different factors. These factors include the relative ease with which a computer virus can be written, the motivation involved in writing a computer virus, the damage and overhead incurred by infected systems, and the legal implications of computer viruses, among others. Based upon the research, the development of a computer virus seems to require more persistence than technical expertise. This is a frightening proclamation to the computing community. The education of computer professionals to the dangers that viruses pose to the welfare of the computing industry as a whole is stressed as a means of inhibiting the current proliferation of computer virus programs. Recommendations are made to assist computer users in preventing infection by computer viruses. These recommendations support solid general computer security practices as a means of combating computer viruses.

  12. Detection of Zoonotic Pathogens and Characterization of Novel Viruses Carried by Commensal Rattus norvegicus in New York City

    PubMed Central

    Bhat, Meera; Firth, Matthew A.; Williams, Simon H.; Frye, Matthew J.; Simmonds, Peter; Conte, Juliette M.; Ng, James; Garcia, Joel; Bhuva, Nishit P.; Lee, Bohyun; Che, Xiaoyu; Quan, Phenix-Lan; Lipkin, W. Ian

    2014-01-01

    ABSTRACT Norway rats (Rattus norvegicus) are globally distributed and concentrate in urban environments, where they live and feed in closer proximity to human populations than most other mammals. Despite the potential role of rats as reservoirs of zoonotic diseases, the microbial diversity present in urban rat populations remains unexplored. In this study, we used targeted molecular assays to detect known bacterial, viral, and protozoan human pathogens and unbiased high-throughput sequencing to identify novel viruses related to agents of human disease in commensal Norway rats in New York City. We found that these rats are infected with bacterial pathogens known to cause acute or mild gastroenteritis in people, including atypical enteropathogenic Escherichia coli, Clostridium difficile, and Salmonella enterica, as well as infectious agents that have been associated with undifferentiated febrile illnesses, including Bartonella spp., Streptobacillus moniliformis, Leptospira interrogans, and Seoul hantavirus. We also identified a wide range of known and novel viruses from groups that contain important human pathogens, including sapoviruses, cardioviruses, kobuviruses, parechoviruses, rotaviruses, and hepaciviruses. The two novel hepaciviruses discovered in this study replicate in the liver of Norway rats and may have utility in establishing a small animal model of human hepatitis C virus infection. The results of this study demonstrate the diversity of microbes carried by commensal rodent species and highlight the need for improved pathogen surveillance and disease monitoring in urban environments. PMID:25316698

  13. Ecology of prokaryotic viruses.

    PubMed

    Weinbauer, Markus G

    2004-05-01

    The finding that total viral abundance is higher than total prokaryotic abundance and that a significant fraction of the prokaryotic community is infected with phages in aquatic systems has stimulated research on the ecology of prokaryotic viruses and their role in ecosystems. This review treats the ecology of prokaryotic viruses ('phages') in marine, freshwater and soil systems from a 'virus point of view'. The abundance of viruses varies strongly in different environments and is related to bacterial abundance or activity suggesting that the majority of the viruses found in the environment are typically phages. Data on phage diversity are sparse but indicate that phages are extremely diverse in natural systems. Lytic phages are predators of prokaryotes, whereas lysogenic and chronic infections represent a parasitic interaction. Some forms of lysogeny might be described best as mutualism. The little existing ecological data on phage populations indicate a large variety of environmental niches and survival strategies. The host cell is the main resource for phages and the resource quality, i.e., the metabolic state of the host cell, is a critical factor in all steps of the phage life cycle. Virus-induced mortality of prokaryotes varies strongly on a temporal and spatial scale and shows that phages can be important predators of bacterioplankton. This mortality and the release of cell lysis products into the environment can strongly influence microbial food web processes and biogeochemical cycles. Phages can also affect host diversity, e.g., by 'killing the winner' and keeping in check competitively dominant species or populations. Moreover, they mediate gene transfer between prokaryotes, but this remains largely unknown in the environment. Genomics or proteomics are providing us now with powerful tools in phage ecology, but final testing will have to be performed in the environment. PMID:15109783

  14. Ecology of prokaryotic viruses.

    PubMed

    Weinbauer, Markus G

    2004-05-01

    The finding that total viral abundance is higher than total prokaryotic abundance and that a significant fraction of the prokaryotic community is infected with phages in aquatic systems has stimulated research on the ecology of prokaryotic viruses and their role in ecosystems. This review treats the ecology of prokaryotic viruses ('phages') in marine, freshwater and soil systems from a 'virus point of view'. The abundance of viruses varies strongly in different environments and is related to bacterial abundance or activity suggesting that the majority of the viruses found in the environment are typically phages. Data on phage diversity are sparse but indicate that phages are extremely diverse in natural systems. Lytic phages are predators of prokaryotes, whereas lysogenic and chronic infections represent a parasitic interaction. Some forms of lysogeny might be described best as mutualism. The little existing ecological data on phage populations indicate a large variety of environmental niches and survival strategies. The host cell is the main resource for phages and the resource quality, i.e., the metabolic state of the host cell, is a critical factor in all steps of the phage life cycle. Virus-induced mortality of prokaryotes varies strongly on a temporal and spatial scale and shows that phages can be important predators of bacterioplankton. This mortality and the release of cell lysis products into the environment can strongly influence microbial food web processes and biogeochemical cycles. Phages can also affect host diversity, e.g., by 'killing the winner' and keeping in check competitively dominant species or populations. Moreover, they mediate gene transfer between prokaryotes, but this remains largely unknown in the environment. Genomics or proteomics are providing us now with powerful tools in phage ecology, but final testing will have to be performed in the environment.

  15. Bagaza virus and Israel turkey meningoencephalomyelitis virus are a single virus species.

    PubMed

    Fernández-Pinero, Jovita; Davidson, Irit; Elizalde, Maia; Perk, Shimon; Khinich, Yevgeny; Jiménez-Clavero, Miguel Angel

    2014-04-01

    Bagaza virus (BAGV) and Israel turkey meningoencephalomyelitis virus (ITV) are classified in the genus Flavivirus of the family Flaviviridae. Serologically, they are closely related, belonging to the Ntaya serocomplex. Nucleotide sequences available to date consist of several complete sequences of BAGV isolates, but only partial sequences of ITV isolates. Sequence comparisons of partial envelope (E) and NS5 regions reveal a close genetic relationship between these viruses. Despite this, BAGV and ITV are considered as separate virus species in the database of the International Committee on Taxonomy of Viruses. In this work, complete nucleotide sequences for five ITV isolates are provided, thereby permitting a phylogenetic comparison with other complete sequences of flaviviruses in the Ntaya serogroup. We conclude that BAGV and ITV are the same virus species and propose that both viruses be designated by a new unified name: Avian meningoencephalomyelitis virus.

  16. [ZIKA--VIRUS INFECTION].

    PubMed

    Velev, V

    2016-01-01

    This review summarizes the knowledge of the scientific community for Zika-virus infection. It became popular because of severe congenital damage causes of CNS in newborns whose mothers are infected during pregnancy, as well as the risk of pandemic distribution. Discusses the peculiarities of the biology and ecology of vectors--blood-sucking mosquitoes Aedes; stages in the spread of infection and practical problems which caused during pregnancy. Attention is paid to the recommendations that allow leading national and international medical organizations to deal with the threat Zika-virus infection. PMID:27509655

  17. Zika virus: Indian perspectives.

    PubMed

    Mourya, Devendra T; Shil, Pratip; Sapkal, Gajanan N; Yadav, Pragya D

    2016-05-01

    The emergence of Zika virus (ZiV), a mosquito borne Flavivirus like dengue (DEN) and chikungunya (CHIK), in Brazil in 2014 and its spread to various countries have led to a global health emergency. Aedes aegypti is the major vector for ZiV. Fast dissemination of this virus in different geographical areas posses a major threat especially to regions where the population lacks herd immunity against the ZiV and there is abundance of Aedes mosquitoes. In this review, we focus on current global scenario, epidemiology, biology, diagnostic challenges and remedial measures for ZiVconsidering the Indian perspective.

  18. Zika Virus Outside Africa

    PubMed Central

    2009-01-01

    Zika virus (ZIKV) is a flavivirus related to yellow fever, dengue, West Nile, and Japanese encephalitis viruses. In 2007 ZIKV caused an outbreak of relatively mild disease characterized by rash, arthralgia, and conjunctivitis on Yap Island in the southwestern Pacific Ocean. This was the first time that ZIKV was detected outside of Africa and Asia. The history, transmission dynamics, virology, and clinical manifestations of ZIKV disease are discussed, along with the possibility for diagnostic confusion between ZIKV illness and dengue.The emergence of ZIKV outside of its previously known geographic range should prompt awareness of the potential for ZIKV to spread to other Pacific islands and the Americas. PMID:19788800

  19. Genome packaging in viruses.

    PubMed

    Sun, Siyang; Rao, Venigalla B; Rossmann, Michael G

    2010-02-01

    Genome packaging is a fundamental process in a viral life cycle. Many viruses assemble preformed capsids into which the genomic material is subsequently packaged. These viruses use a packaging motor protein that is driven by the hydrolysis of ATP to condense the nucleic acids into a confined space. How these motor proteins package viral genomes had been poorly understood until recently, when a few X-ray crystal structures and cryo-electron microscopy (cryo-EM) structures became available. Here we discuss various aspects of genome packaging and compare the mechanisms proposed for packaging motors on the basis of structural information. PMID:20060706

  20. [ZIKA--VIRUS INFECTION].

    PubMed

    Velev, V

    2016-01-01

    This review summarizes the knowledge of the scientific community for Zika-virus infection. It became popular because of severe congenital damage causes of CNS in newborns whose mothers are infected during pregnancy, as well as the risk of pandemic distribution. Discusses the peculiarities of the biology and ecology of vectors--blood-sucking mosquitoes Aedes; stages in the spread of infection and practical problems which caused during pregnancy. Attention is paid to the recommendations that allow leading national and international medical organizations to deal with the threat Zika-virus infection.

  1. Virus diseases of fish

    USGS Publications Warehouse

    Watson, Stanley W.

    1954-01-01

    The degenerative or non-neoplastic diseases of possible virus origin give the fish-culturist the most concern because of the severe mortalities resulting from infection. Epizootics of this nature have been reported in carp (Cyprinus carpio) and rainbow trout (Salmo gairdneri) in Europe, in acara (Geophagus brasiliensis) in South America, in kokanee, (Oncorhynchus nerka kennerlyi) and in sockeye salmon (Oncorhynchus nerka nerka) in the State of Washington. It has been demonstrated that each epizootic was caused by an infectious filterable agent, probably a virus.

  2. Schmallenberg virus infection.

    PubMed

    Wernike, K; Elbers, A; Beer, M

    2015-08-01

    Since Schmallenberg virus, an orthobunyavirus of the Simbu serogroup, was identified near the German-Dutch border for the first time in late 2011 it has spread extremely quickly and caused a large epidemic in European livestock. The virus, which is transmitted by Culicoides biting midges, infects domestic and wild ruminants. Adult animals show only mild clinical symptoms or none at all, whereas an infection during a critical period of gestation can lead to abortion, stillbirth or the birth of severely malformed offspring. The impact of the disease is usually greater in sheep than in cattle. Vaccination could be an important aspect of disease control. PMID:26601441

  3. Zika virus outside Africa.

    PubMed

    Hayes, Edward B

    2009-09-01

    Zika virus (ZIKV) is a flavivirus related to yellow fever, dengue, West Nile, and Japanese encephalitis viruses. In 2007 ZIKV caused an outbreak of relatively mild disease characterized by rash, arthralgia, and conjunctivitis on Yap Island in the southwestern Pacific Ocean. This was the first time that ZIKV was detected outside of Africa and Asia. The history, transmission dynamics, virology, and clinical manifestations of ZIKV disease are discussed, along with the possibility for diagnostic confusion between ZIKV illness and dengue.The emergence of ZIKV outside of its previously known geographic range should prompt awareness of the potential for ZIKV to spread to other Pacific islands and the Americas.

  4. Viruses and viral proteins

    PubMed Central

    Verdaguer, Nuria; Ferrero, Diego; Murthy, Mathur R. N.

    2014-01-01

    For more than 30 years X-ray crystallography has been by far the most powerful approach for determining the structures of viruses and viral proteins at atomic resolution. The information provided by these structures, which covers many important aspects of the viral life cycle such as cell-receptor recognition, viral entry, nucleic acid transfer and genome replication, has extensively enriched our vision of the virus world. Many of the structures available correspond to potential targets for antiviral drugs against important human pathogens. This article provides an overview of the current knowledge of different structural aspects of the above-mentioned processes. PMID:25485129

  5. Zika virus: Indian perspectives

    PubMed Central

    Mourya, Devendra T.; Shil, Pratip; Sapkal, Gajanan N.; Yadav, Pragya D.

    2016-01-01

    The emergence of Zika virus (ZiV), a mosquito borne Flavivirus like dengue (DEN) and chikungunya (CHIK), in Brazil in 2014 and its spread to various countries have led to a global health emergency. Aedes aegypti is the major vector for ZiV. Fast dissemination of this virus in different geographical areas posses a major threat especially to regions where the population lacks herd immunity against the ZiV and there is abundance of Aedes mosquitoes. In this review, we focus on current global scenario, epidemiology, biology, diagnostic challenges and remedial measures for ZiVconsidering the Indian perspective. PMID:27487998

  6. Human Immunodeficiency Virus Prevention.

    PubMed

    Davis, Teaniese Latham; DiClemente, Ralph

    2016-04-01

    Human immunodeficiency virus (HIV) is the virus that causes AIDS. Surveillance data from 2012 indicate an estimated 1.2 million people aged 13 years and older were living with HIV infection in the United States, and 12.8% do not know their status. There are approximately 50,000 new HIV infections annually. With no available cure for HIV, primary prevention to reduce incident cases of HIV is essential. Strategies to prevent HIV transmission include reducing sexual risk behavior and needle sharing. The Centers for Disease Control and Prevention has multiple resources available for primary and secondary prevention to reduce disease transmission and severity. PMID:26980130

  7. Zika virus: Indian perspectives.

    PubMed

    Mourya, Devendra T; Shil, Pratip; Sapkal, Gajanan N; Yadav, Pragya D

    2016-05-01

    The emergence of Zika virus (ZiV), a mosquito borne Flavivirus like dengue (DEN) and chikungunya (CHIK), in Brazil in 2014 and its spread to various countries have led to a global health emergency. Aedes aegypti is the major vector for ZiV. Fast dissemination of this virus in different geographical areas posses a major threat especially to regions where the population lacks herd immunity against the ZiV and there is abundance of Aedes mosquitoes. In this review, we focus on current global scenario, epidemiology, biology, diagnostic challenges and remedial measures for ZiVconsidering the Indian perspective. PMID:27487998

  8. Research on computer virus database management system

    NASA Astrophysics Data System (ADS)

    Qi, Guoquan

    2011-12-01

    The growing proliferation of computer viruses becomes the lethal threat and research focus of the security of network information. While new virus is emerging, the number of viruses is growing, virus classification increasing complex. Virus naming because of agencies' capture time differences can not be unified. Although each agency has its own virus database, the communication between each other lacks, or virus information is incomplete, or a small number of sample information. This paper introduces the current construction status of the virus database at home and abroad, analyzes how to standardize and complete description of virus characteristics, and then gives the information integrity, storage security and manageable computer virus database design scheme.

  9. Epidemiology of hemorrhagic fever viruses.

    PubMed

    LeDuc, J W

    1989-01-01

    Twelve distinct viruses associated with hemorrhagic fever in humans are classified among four families: Arenaviridae, which includes Lassa, Junin, and Machupo viruses; Bunyaviridae, which includes Rift Valley fever, Crimean-Congo hemorrhagic fever, and Hantaan viruses; Filoviridae, which includes Marburg and Ebola viruses; and Flaviviridae, which includes yellow fever, dengue, Kyasanur Forest disease, and Omsk viruses. Most hemorrhagic fever viruses are zoonoses, with the possible exception of the four dengue viruses, which may continually circulate among humans. Hemorrhagic fever viruses are found in both temperate and tropical habitats and generally infect both sexes and all ages, although the age and sex of those infected are frequently influenced by the possibility of occupational exposure. Transmission to humans is frequently by bite of an infected tick or mosquito or via aerosol from infected rodent hosts. Aerosol and nosocomial transmission are especially important with Lassa, Junin, Machupo, Crimean-Congo hemorrhagic fever, Marburg, and Ebola viruses. Seasonality of hemorrhagic fever among humans is influenced for the most part by the dynamics of infected arthropod or vertebrate hosts. Mammals, especially rodents, appear to be important natural hosts for many hemorrhagic fever viruses. The transmission cycle for each hemorrhagic fever virus is distinct and is dependent upon the characteristics of the primary vector species and the possibility for its contact with humans.

  10. Turnip Yellow Mosaic Virus

    NASA Technical Reports Server (NTRS)

    2000-01-01

    The bumpy exterior of the turnip yellow mosaic virus (TYMV) protein coat, or capsid, was defined in detail by Dr. Alexander McPherson of the University of California, Irvin using proteins crystallized in space for analysis on Earth. TYMV is an icosahedral virus constructed from 180 copies of the same protein arranged into 12 clusters of five proteins (pentamers), and 20 clusters of six proteins (hexamers). The final TYMV structure led to the unexpected hypothesis that the virus releases its RNA by essentially chemical-mechanical means. Most viruses have fairly flat coats, but in TYNV, the fold in each protein, called the jellyroll, is clustered at the points where the protein pentamers and hexamers join. The jellyrolls are almost standing on end, producing a bumpy surface with knobs at all of the pentamers and hexamers. At the inside surface of the pentamers is a void that is not present at the hexamers. The coating had been seen in early stuties of TYMV, but McPherson's atomic structure shows much more detail. The inside surface is strikingly, and unexpectedly, different than the outside. While the pentamers contain a central void on the inside, the hexameric units contain peptides linked to each other, forming a ring or, more accurately, rings to fill the void. Credit: Dr. Alexander McPherson, University of California, Irvine

  11. From Shakespeare to Viruses

    ScienceCinema

    Sung-Hou Kim

    2010-01-08

    Berkeley Lab scientists have created a unique new tool for analyzing and comparing long sets of data, be it the genomes of mammals or viruses, or the works of Shakespeare. The results of the Shakespeare analysis surprised scholars with their accuracy

  12. Viruses of haloarchaea.

    PubMed

    Luk, Alison W S; Williams, Timothy J; Erdmann, Susanne; Papke, R Thane; Cavicchioli, Ricardo

    2014-01-01

    In hypersaline environments, haloarchaea (halophilic members of the Archaea) are the dominant organisms, and the viruses that infect them, haloarchaeoviruses are at least ten times more abundant. Since their discovery in 1974, described haloarchaeoviruses include head-tailed, pleomorphic, spherical and spindle-shaped morphologies, representing Myoviridae, Siphoviridae, Podoviridae, Pleolipoviridae, Sphaerolipoviridae and Fuselloviridae families. This review overviews current knowledge of haloarchaeoviruses, providing information about classification, morphotypes, macromolecules, life cycles, genetic manipulation and gene regulation, and host-virus responses. In so doing, the review incorporates knowledge from laboratory studies of isolated viruses, field-based studies of environmental samples, and both genomic and metagenomic analyses of haloarchaeoviruses. What emerges is that some haloarchaeoviruses possess unique morphological and life cycle properties, while others share features with other viruses (e.g., bacteriophages). Their interactions with hosts influence community structure and evolution of populations that exist in hypersaline environments as diverse as seawater evaporation ponds, to hot desert or Antarctic lakes. The discoveries of their wide-ranging and important roles in the ecology and evolution of hypersaline communities serves as a strong motivator for future investigations of both laboratory-model and environmental systems. PMID:25402735

  13. From Shakespeare to Viruses

    SciTech Connect

    Sung-Hou Kim

    2009-02-09

    Berkeley Lab scientists have created a unique new tool for analyzing and comparing long sets of data, be it the genomes of mammals or viruses, or the works of Shakespeare. The results of the Shakespeare analysis surprised scholars with their accuracy

  14. From Shakespeare to Viruses

    ScienceCinema

    Kim, Sung-Hou

    2013-05-29

    Berkeley Lab scientists have created a unique new tool for analyzing and comparing long sets of data, be it the genomes of mammals or viruses, or the works of Shakespeare. The results of the Shakespeare analysis surprised scholars with their accuracy.

  15. Human Viruses and Cancer

    PubMed Central

    Morales-Sánchez, Abigail; Fuentes-Pananá, Ezequiel M.

    2014-01-01

    The first human tumor virus was discovered in the middle of the last century by Anthony Epstein, Bert Achong and Yvonne Barr in African pediatric patients with Burkitt’s lymphoma. To date, seven viruses -EBV, KSHV, high-risk HPV, MCPV, HBV, HCV and HTLV1- have been consistently linked to different types of human cancer, and infections are estimated to account for up to 20% of all cancer cases worldwide. Viral oncogenic mechanisms generally include: generation of genomic instability, increase in the rate of cell proliferation, resistance to apoptosis, alterations in DNA repair mechanisms and cell polarity changes, which often coexist with evasion mechanisms of the antiviral immune response. Viral agents also indirectly contribute to the development of cancer mainly through immunosuppression or chronic inflammation, but also through chronic antigenic stimulation. There is also evidence that viruses can modulate the malignant properties of an established tumor. In the present work, causation criteria for viruses and cancer will be described, as well as the viral agents that comply with these criteria in human tumors, their epidemiological and biological characteristics, the molecular mechanisms by which they induce cellular transformation and their associated cancers. PMID:25341666

  16. From Shakespeare to Viruses

    SciTech Connect

    Kim, Sung-Hou

    2009-01-01

    Berkeley Lab scientists have created a unique new tool for analyzing and comparing long sets of data, be it the genomes of mammals or viruses, or the works of Shakespeare. The results of the Shakespeare analysis surprised scholars with their accuracy.

  17. Cold Facts about Viruses.

    ERIC Educational Resources Information Center

    Pea, Celeste; Sterling, Donna R.

    2002-01-01

    Provides ways for students to demonstrate their understanding of scientific concepts and skills. Describes a mini-unit around the cold in which students can relate humans to viruses. Includes activities and a modified simulation that provides questions to guide students. Discusses ways that allows students to apply prior knowledge, take ownership…

  18. Viruses of Haloarchaea

    PubMed Central

    Luk, Alison W. S.; Williams, Timothy J.; Erdmann, Susanne; Papke, R. Thane; Cavicchioli, Ricardo

    2014-01-01

    In hypersaline environments, haloarchaea (halophilic members of the Archaea) are the dominant organisms, and the viruses that infect them, haloarchaeoviruses are at least ten times more abundant. Since their discovery in 1974, described haloarchaeoviruses include head-tailed, pleomorphic, spherical and spindle-shaped morphologies, representing Myoviridae, Siphoviridae, Podoviridae, Pleolipoviridae, Sphaerolipoviridae and Fuselloviridae families. This review overviews current knowledge of haloarchaeoviruses, providing information about classification, morphotypes, macromolecules, life cycles, genetic manipulation and gene regulation, and host-virus responses. In so doing, the review incorporates knowledge from laboratory studies of isolated viruses, field-based studies of environmental samples, and both genomic and metagenomic analyses of haloarchaeoviruses. What emerges is that some haloarchaeoviruses possess unique morphological and life cycle properties, while others share features with other viruses (e.g., bacteriophages). Their interactions with hosts influence community structure and evolution of populations that exist in hypersaline environments as diverse as seawater evaporation ponds, to hot desert or Antarctic lakes. The discoveries of their wide-ranging and important roles in the ecology and evolution of hypersaline communities serves as a strong motivator for future investigations of both laboratory-model and environmental systems. PMID:25402735

  19. Satellite RNAs and Satellite Viruses.

    PubMed

    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.

  20. Bat flight and zoonotic viruses

    USGS Publications Warehouse

    O'Shea, Thomas; Cryan, Paul M.; Cunningham, Andrew A.; Fooks, Anthony R.; Hayman, David T.S.; Luis, Angela D.; Peel, Alison J.; Plowright, Raina K.; Wood, James L.N.

    2014-01-01

    Bats are sources of high viral diversity and high-profile zoonotic viruses worldwide. Although apparently not pathogenic in their reservoir hosts, some viruses from bats severely affect other mammals, including humans. Examples include severe acute respiratory syndrome coronaviruses, Ebola and Marburg viruses, and Nipah and Hendra viruses. Factors underlying high viral diversity in bats are the subject of speculation. We hypothesize that flight, a factor common to all bats but to no other mammals, provides an intensive selective force for coexistence with viral parasites through a daily cycle that elevates metabolism and body temperature analogous to the febrile response in other mammals. On an evolutionary scale, this host–virus interaction might have resulted in the large diversity of zoonotic viruses in bats, possibly through bat viruses adapting to be more tolerant of the fever response and less virulent to their natural hosts.

  1. Bat flight and zoonotic viruses.

    PubMed

    O'Shea, Thomas J; Cryan, Paul M; Cunningham, Andrew A; Fooks, Anthony R; Hayman, David T S; Luis, Angela D; Peel, Alison J; Plowright, Raina K; Wood, James L N

    2014-05-01

    Bats are sources of high viral diversity and high-profile zoonotic viruses worldwide. Although apparently not pathogenic in their reservoir hosts, some viruses from bats severely affect other mammals, including humans. Examples include severe acute respiratory syndrome coronaviruses, Ebola and Marburg viruses, and Nipah and Hendra viruses. Factors underlying high viral diversity in bats are the subject of speculation. We hypothesize that flight, a factor common to all bats but to no other mammals, provides an intensive selective force for coexistence with viral parasites through a daily cycle that elevates metabolism and body temperature analogous to the febrile response in other mammals. On an evolutionary scale, this host-virus interaction might have resulted in the large diversity of zoonotic viruses in bats, possibly through bat viruses adapting to be more tolerant of the fever response and less virulent to their natural hosts.

  2. Rat Bite Fever

    MedlinePlus

    ... Issues Listen Español Text Size Email Print Share Rat Bite Fever Page Content Article Body Rat-bite fever is a disease that occurs in humans who have been bitten by an infected rat or, in some cases, squirrels, mice, cats, and ...

  3. An efficient deletion mutant packaging system for defective herpes simplex virus vectors: Potential applications to human gene therapy and neuronal physiology

    SciTech Connect

    Geller, A.I.; Keyomarsi, K.; Bryan, J.; Pardee, A.B. )

    1990-11-01

    The authors have previously described a defective herpes simplex virus (HSV-1) vector system that permits that introduction of virtually any gene into nonmitotic cells. pHSVlac, the prototype vector, stably expresses Escherichia coli {beta}-galactosidase from a constitutive promoter in many human cell lines, in cultured rat neurons from throughout the nervous system, and in cells in the adult rat brain. HSV-1 vectors expressing other genes may prove useful for studying neuronal physiology or performing human gene therapy for neurological diseases, such as Parkinson disease or brain tumors. A HSV-1 temperature-sensitive (ts) mutant, ts K, has been used as helper virus; ts mutants revert to wild type. In contrast, HSV-1 deletion mutants essentially cannot revert to wild type; therefore, use of a deletion mutant as helper virus might permit human gene therapy with HSV-1 vectors. They now report an efficient packaging system for HSV-1 VECTORS USING A DELETION MUTANT, d30EBA, as helper virus; virus is grown on the complementing cell line M64A. pHSVlac virus prepared using the deletion mutant packaging system stably expresses {beta}-galactosidase in cultured rat sympathetic neurons and glia. Both D30EBA and ts K contain a mutation in the IE3 gene of HSV-1 strain 17 and have the same phenotype; therefore, changing the helper virus from ts K to D30EBA does not alter the host range or other properties of the HSV-1 vector system.

  4. Membrane-bound complement regulatory activity is decreased on vaccinia virus-infected cells.

    PubMed Central

    Baranyi, L; Okada, N; Baranji, K; Takizawa, H; Okada, H

    1994-01-01

    Decay accelerating factor (DAF), membrane cofactor protein (MCP), complement receptor 1 and mouse Crry are cell surface-bound complement regulatory proteins capable of inhibiting C3 convertase activity on cell membranes, and therefore provide a substantial protection from attack by homologous complement activated either by the classical or by the alternative pathway. Decrease in complement regulatory activity might lead to spontaneous complement deposition and subsequent cell injury. MoAb 5I2 can inhibit the complement regulatory activity of molecules on rat cells, resulting in deposition of homologous complement. The antigen recognized by 5I2 MoAb in rats is homologous to mouse Crry. Fifteen to 20 h after infection with vaccinia virus, in vitro cultured KDH-8 rat hepatoma cells show a strong decrease in expression of Crry-like antigen, and proved to be sensitive to complement deposition when 1:5 diluted normal rat serum was added to the culture medium as a source of complement. Addition of complement to the cultured KDH-8 cells infected with a very low dose of vaccinia virus (1 plaque-forming unit (PFU)/1000 cells) substantially reduced spreading of virus infection in the cell culture, while inactivation of complement by heat or zymosan treatment abrogated the protective effect. PMID:7923872

  5. A vaccinia virus renaissance

    PubMed Central

    Verardi, Paulo H.; Titong, Allison; Hagen, Caitlin J.

    2012-01-01

    In 1796, Edward Jenner introduced the concept of vaccination with cowpox virus, an Orthopoxvirus within the family Poxviridae that elicits cross protective immunity against related orthopoxviruses, including smallpox virus (variola virus). Over time, vaccinia virus (VACV) replaced cowpox virus as the smallpox vaccine, and vaccination efforts eventually led to the successful global eradication of smallpox in 1979. VACV has many characteristics that make it an excellent vaccine and that were crucial for the successful eradication of smallpox, including (1) its exceptional thermal stability (a very important but uncommon characteristic in live vaccines), (2) its ability to elicit strong humoral and cell-mediated immune responses, (3) the fact that it is easy to propagate, and (4) that it is not oncogenic, given that VACV replication occurs exclusively within the host cell cytoplasm and there is no evidence that the viral genome integrates into the host genome. Since the eradication of smallpox, VACV has experienced a renaissance of interest as a viral vector for the development of recombinant vaccines, immunotherapies, and oncolytic therapies, as well as the development of next-generation smallpox vaccines. This revival is mainly due to the successful use and extensive characterization of VACV as a vaccine during the smallpox eradication campaign, along with the ability to genetically manipulate its large dsDNA genome while retaining infectivity and immunogenicity, its wide mammalian host range, and its natural tropism for tumor cells that allows its use as an oncolytic vector. This review provides an overview of new uses of VACV that are currently being explored for the development of vaccines, immunotherapeutics, and oncolytic virotherapies. PMID:22777090

  6. Molecular epidemiology of respiratory viruses in virus-induced asthma

    PubMed Central

    Ishioka, Taisei; Noda, Masahiro; Kozawa, Kunihisa; Kimura, Hirokazu

    2013-01-01

    Acute respiratory illness (ARI) due to various viruses is not only the most common cause of upper respiratory infection in humans but is also a major cause of morbidity and mortality, leading to diseases such as bronchiolitis and pneumonia. Previous studies have shown that respiratory syncytial virus (RSV), human rhinovirus (HRV), human metapneumovirus (HMPV), human parainfluenza virus (HPIV), and human enterovirus infections may be associated with virus-induced asthma. For example, it has been suggested that HRV infection is detected in the acute exacerbation of asthma and infection is prolonged. Thus it is believed that the main etiological cause of asthma is ARI viruses. Furthermore, the number of asthma patients in most industrial countries has greatly increased, resulting in a morbidity rate of around 10-15% of the population. However, the relationships between viral infections, host immune response, and host factors in the pathophysiology of asthma remain unclear. To gain a better understanding of the epidemiology of virus-induced asthma, it is important to assess both the characteristics of the viruses and the host defense mechanisms. Molecular epidemiology enables us to understand the pathogenesis of microorganisms by identifying specific pathways, molecules, and genes that influence the risk of developing a disease. However, the epidemiology of various respiratory viruses associated with virus-induced asthma is not fully understood. Therefore, in this article, we review molecular epidemiological studies of RSV, HRV, HPIV, and HMPV infection associated with virus-induced asthma. PMID:24062735

  7. Regulatory T cells enhance persistence of the zoonotic pathogen Seoul virus in its reservoir host.

    PubMed

    Easterbrook, Judith D; Zink, M Christine; Klein, Sabra L

    2007-09-25

    Hantaviruses are zoonotic pathogens that maintain a persistent infection in their reservoir hosts, yet the mechanisms mediating persistence remain unknown. Regulatory T cell responses cause persistent infection by suppressing proinflammatory and effector T cell activity; hantaviruses may exploit these responses to cause persistence. To test this hypothesis, male Norway rats were inoculated with Seoul virus and regulatory T cells were monitored during infection. Increased numbers of CD4(+)CD25(+)Forkhead box P3(+) T cells and expression of Forkhead box P3 and TGF-beta were observed in the lungs of male rats during persistent Seoul virus infection. To determine whether regulatory T cells modulate Seoul virus persistence, regulatory T cells were inactivated in male rats by using an anti-rat CD25 monoclonal antibody (NDS-63). Inactivation of regulatory T cells reduced the amount of Seoul virus RNA present in the lungs and the proportion of animals shedding viral RNA in saliva. Because regulatory T cells suppress proinflammatory-induced pathogenesis, pathologic observations in the lungs were evaluated during infection. Subclinical acute multifocal areas of hemorrhage and edema were noted in the lungs during infection; inactivation of regulatory T cells reduced the amount of pathologic foci. Expression of TNF was suppressed during the persistent phase of infection; inactivation of regulatory T cells eliminated the suppression of TNF. Taken together, these data suggest that regulatory T cells mediate Seoul virus persistence, possibly through elevated transcription and synthesis of TGF-beta and suppression of TNF. These data provide evidence of regulatory T cell involvement in the persistence of a zoonotic pathogen in its natural reservoir host.

  8. Animal models of human respiratory syncytial virus disease

    PubMed Central

    Domachowske, Joseph B.; Rosenberg, Helene F.

    2011-01-01

    Infection with the human pneumovirus pathogen, respiratory syncytial virus (hRSV), causes a wide spectrum of respiratory disease, notably among infants and the elderly. Laboratory animal studies permit detailed experimental modeling of hRSV disease and are therefore indispensable in the search for novel therapies and preventative strategies. Present animal models include several target species for hRSV, including chimpanzees, cattle, sheep, cotton rats, and mice, as well as alternative animal pneumovirus models, such as bovine RSV and pneumonia virus of mice. These diverse animal models reproduce different features of hRSV disease, and their utilization should therefore be based on the scientific hypothesis under investigation. The purpose of this review is to summarize the strengths and limitations of each of these animal models. Our intent is to provide a resource for investigators and an impetus for future research. PMID:21571908

  9. Fatal Cowpox Virus Infection in an Aborted Foal.

    PubMed

    Franke, Annika; Kershaw, Olivia; Jenckel, Maria; König, Lydia; Beer, Martin; Hoffmann, Bernd; Hoffmann, Donata

    2016-06-01

    The article describes the isolation of a cowpox virus (CPXV) isolate originating from a horse. The skin of a foal, aborted in the third trimester, displayed numerous cutaneous papules. The histological examination showed A-type inclusion bodies within the lesion, typical for CPXV infections. This suspicion was confirmed by real-time PCR where various organs were analyzed. From skin samples, virus isolation was successfully performed. Afterwards, the whole genome of this new isolate "CPXV Amadeus" was sequenced by next-generation technology. Phylogenetic analysis clearly showed that "CPXV Amadeus" belongs to the "CPXV-like 1" clade. To our opinion, the study provides important additional information on rare accidental CPXV infections. From the natural hosts, the voles, species such as rats, cats, or different zoo animals are occasionally infected, but until now only two horse cases are described. In addition, there are new insights toward congenital CPXV infections. PMID:27159333

  10. Recovery of infectious virus from full-length cowpox virus (CPXV) DNA cloned as a bacterial artificial chromosome (BAC).

    PubMed

    Roth, Swaantje J; Höper, Dirk; Beer, Martin; Feineis, Silke; Tischer, B Karsten; Osterrieder, Nikolaus

    2011-01-01

    Transmission from pet rats and cats to humans as well as severe infection in felids and other animal species have recently drawn increasing attention to cowpox virus (CPXV). We report the cloning of the entire genome of cowpox virus strain Brighton Red (BR) as a bacterial artificial chromosome (BAC) in Escherichia coli and the recovery of infectious virus from cloned DNA. Generation of a full-length CPXV DNA clone was achieved by first introducing a mini-F vector, which allows maintenance of large circular DNA in E. coli, into the thymidine kinase locus of CPXV by homologous recombination. Circular replication intermediates were then electroporated into E. coli DH10B cells. Upon successful establishment of the infectious BR clone, we modified the full-length clone such that recombination-mediated excision of bacterial sequences can occur upon transfection in eukaryotic cells. This self-excision of the bacterial replicon is made possible by a sequence duplication within mini-F sequences and allows recovery of recombinant virus progeny without remaining marker or vector sequences. The in vitro growth properties of viruses derived from both BAC clones were determined and found to be virtually indistinguishable from those of parental, wild-type BR. Finally, the complete genomic sequence of the infectious clone was determined and the cloned viral genome was shown to be identical to that of the parental virus. In summary, the generated infectious clone will greatly facilitate studies on individual genes and pathogenesis of CPXV. Moreover, the vector potential of CPXV can now be more systematically explored using this newly generated tool. PMID:21314965

  11. Different patterns of neuronal infection after intracerebral injection of two strains of pseudorabies virus.

    PubMed

    Card, J P; Levitt, P; Enquist, L W

    1998-05-01

    Pseudorabies virus (PRV), a swine neurotropic alphaherpesvirus, is known to invade the central nervous system (CNS) of a variety of animal species through peripherally projecting axons, replicate in the parent neurons, and then pass transsynaptically to infect other neurons of a circuit. Studies of the human pathogen herpes simplex virus type 1 have reported differences in the direction of transport of two strains of this virus after direct injection into the primate motor cortex. In the present study we examined the direction of transport of virulent and attenuated strains of PRV, utilizing injections into the rat prefrontal cortex to evaluate specific movement of virus through CNS circuitry. The data demonstrate strain-dependent patterns of infection consistent with bidirectional (anterograde and retrograde) transport of virulent virus and unidirectional (retrograde) transport of attenuated PRV from the site of injection. The distribution of infected neurons and the extent of transsynaptic passage also suggest that a release defect in the attenuated strain reduces the apparent rate of viral transport through neuronal circuitry. Finally, injection of different concentrations of virus influenced the onset of replication within a neural circuit. Taken together, these data suggest that viral envelope glycoproteins and virus concentration at the site of injection are important determinants of the rate and direction of viral transport through a multisynaptic circuit in the CNS.

  12. Zoonotic viruses associated with illegally imported wildlife products

    USGS Publications Warehouse

    Smith, Kristine M.; Anthony, Simon J.; Switzer, William M.; Epstein, Jonathan H.; Seimon, Tracie; Jia, Hongwei; Sanchez, Maria D.; Huynh, Thanh Thao; Galland, G. Gale; Shapiro, Sheryl E.; Sleeman, Jonathan M.; McAloose, Denise; Stuchin, Margot; Amato, George; Kolokotronis, Sergios-Orestis; Lipkin, W. Ian; Karesh, William B.; Daszak, Peter; Marano, Nina

    2012-01-01

    The global trade in wildlife has historically contributed to the emergence and spread of infectious diseases. The United States is the world's largest importer of wildlife and wildlife products, yet minimal pathogen surveillance has precluded assessment of the health risks posed by this practice. This report details the findings of a pilot project to establish surveillance methodology for zoonotic agents in confiscated wildlife products. Initial findings from samples collected at several international airports identified parts originating from nonhuman primate (NHP) and rodent species, including baboon, chimpanzee, mangabey, guenon, green monkey, cane rat and rat. Pathogen screening identified retroviruses (simian foamy virus) and/or herpesviruses (cytomegalovirus and lymphocryptovirus) in the NHP samples. These results are the first demonstration that illegal bushmeat importation into the United States could act as a conduit for pathogen spread, and suggest that implementation of disease surveillance of the wildlife trade will help facilitate prevention of disease emergence.

  13. Zoonotic Viruses Associated with Illegally Imported Wildlife Products

    PubMed Central

    Switzer, William M.; Epstein, Jonathan H.; Seimon, Tracie; Jia, Hongwei; Sanchez, Maria D.; Huynh, Thanh Thao; Galland, G. Gale; Shapiro, Sheryl E.; Sleeman, Jonathan M.; McAloose, Denise; Stuchin, Margot; Amato, George; Kolokotronis, Sergios-Orestis; Lipkin, W. Ian; Karesh, William B.; Daszak, Peter; Marano, Nina

    2012-01-01

    The global trade in wildlife has historically contributed to the emergence and spread of infectious diseases. The United States is the world's largest importer of wildlife and wildlife products, yet minimal pathogen surveillance has precluded assessment of the health risks posed by this practice. This report details the findings of a pilot project to establish surveillance methodology for zoonotic agents in confiscated wildlife products. Initial findings from samples collected at several international airports identified parts originating from nonhuman primate (NHP) and rodent species, including baboon, chimpanzee, mangabey, guenon, green monkey, cane rat and rat. Pathogen screening identified retroviruses (simian foamy virus) and/or herpesviruses (cytomegalovirus and lymphocryptovirus) in the NHP samples. These results are the first demonstration that illegal bushmeat importation into the United States could act as a conduit for pathogen spread, and suggest that implementation of disease surveillance of the wildlife trade will help facilitate prevention of disease emergence. PMID:22253731

  14. Zoonotic viruses associated with illegally imported wildlife products.

    PubMed

    Smith, Kristine M; Anthony, Simon J; Switzer, William M; Epstein, Jonathan H; Seimon, Tracie; Jia, Hongwei; Sanchez, Maria D; Huynh, Thanh Thao; Galland, G Gale; Shapiro, Sheryl E; Sleeman, Jonathan M; McAloose, Denise; Stuchin, Margot; Amato, George; Kolokotronis, Sergios-Orestis; Lipkin, W Ian; Karesh, William B; Daszak, Peter; Marano, Nina

    2012-01-01

    The global trade in wildlife has historically contributed to the emergence and spread of infectious diseases. The United States is the world's largest importer of wildlife and wildlife products, yet minimal pathogen surveillance has precluded assessment of the health risks posed by this practice. This report details the findings of a pilot project to establish surveillance methodology for zoonotic agents in confiscated wildlife products. Initial findings from samples collected at several international airports identified parts originating from nonhuman primate (NHP) and rodent species, including baboon, chimpanzee, mangabey, guenon, green monkey, cane rat and rat. Pathogen screening identified retroviruses (simian foamy virus) and/or herpesviruses (cytomegalovirus and lymphocryptovirus) in the NHP samples. These results are the first demonstration that illegal bushmeat importation into the United States could act as a conduit for pathogen spread, and suggest that implementation of disease surveillance of the wildlife trade will help facilitate prevention of disease emergence.

  15. Pygmy Rice Rat as Potential Host of Castelo dos Sonhos Hantavirus

    PubMed Central

    Travassos da Rosa, Elizabeth S.; Medeiros, Daniele B. A.; Nunes, Márcio R.T.; Simith, Darlene B.; Pereira, Armando de Souza; Elkhoury, Mauro R.; Lavocat, Marília; Marques, Aparecido A.R.; Via, Alba Valéria; D’Andrea, Paulo; Bonvicino, Cibele R.; Lemos, Elba Regina S.

    2011-01-01

    To study the dynamics of wild rodent populations and identify potential hosts for hantavirus, we conducted an eco-epidemiologic study in Campo Novo do Parecis, Mato Grosso State, Brazil. We detected and genetically characterized Castelo dos Sonhos virus found in a species of pygmy rice rat (Oligoryzomys utiaritensis). PMID:21801642

  16. A Transgenic Rat for Specifically Inhibiting Adult Neurogenesis123

    PubMed Central

    Grigereit, Laura; Pickel, James

    2016-01-01

    Abstract The growth of research on adult neurogenesis and the development of new models and tools have greatly advanced our understanding of the function of newborn neurons in recent years. However, there are still significant limitations in the ability to identify the functions of adult neurogenesis in available models. Here we report a transgenic rat (TK rat) that expresses herpes simplex virus thymidine kinase in GFAP+ cells. Upon treating TK rats with the antiviral drug valganciclovir, granule cell neurogenesis can be completely inhibited in adulthood, in both the hippocampus and olfactory bulb. Interestingly, neurogenesis in the glomerular and external plexiform layers of the olfactory bulb was only partially inhibited, suggesting that some adult-born neurons in these regions derive from a distinct precursor population that does not express GFAP. Within the hippocampus, blockade of neurogenesis was rapid and nearly complete within 1 week of starting treatment. Preliminary behavioral analyses indicate that general anxiety levels and patterns of exploration are generally unaffected in neurogenesis-deficient rats. However, neurogenesis-deficient TK rats showed reduced sucrose preference, suggesting deficits in reward-related behaviors. We expect that TK rats will facilitate structural, physiological, and behavioral studies that complement those possible in existing models, broadly enhancing understanding of the function of adult neurogenesis. PMID:27257630

  17. Neuroteratogenic Viruses and Lessons for Zika Virus Models.

    PubMed

    Kim, Kenneth; Shresta, Sujan

    2016-08-01

    The Centers for Disease Control and Prevention has confirmed that Zika virus (ZIKV) causes congenital microcephaly. ZIKV now joins five other neuroteratogenic (NT) viruses in humans and ZIKV research is in its infancy. In addition, there is only one other NT human arbovirus (Venezuelan equine encephalitis virus), which is also poorly understood. But further insight into ZIKV can be found by evaluating arboviruses in domestic animals, of which there are at least seven NT viruses, three of which have been well studied. Here we review two key anatomical structures involved in modeling transplacental NT virus transmission: the placenta and the fetal blood-brain barrier. We then survey major research findings regarding transmission of NT viruses for guidance in establishing a mouse model of Zika disease that is crucial for a better understanding of ZIKV transmission and pathogenesis. PMID:27387029

  18. Neuroteratogenic Viruses and Lessons for Zika Virus Models.

    PubMed

    Kim, Kenneth; Shresta, Sujan

    2016-08-01

    The Centers for Disease Control and Prevention has confirmed that Zika virus (ZIKV) causes congenital microcephaly. ZIKV now joins five other neuroteratogenic (NT) viruses in humans and ZIKV research is in its infancy. In addition, there is only one other NT human arbovirus (Venezuelan equine encephalitis virus), which is also poorly understood. But further insight into ZIKV can be found by evaluating arboviruses in domestic animals, of which there are at least seven NT viruses, three of which have been well studied. Here we review two key anatomical structures involved in modeling transplacental NT virus transmission: the placenta and the fetal blood-brain barrier. We then survey major research findings regarding transmission of NT viruses for guidance in establishing a mouse model of Zika disease that is crucial for a better understanding of ZIKV transmission and pathogenesis.

  19. Single Virus Genomics: A New Tool for Virus Discovery

    PubMed Central

    Allen, Lisa Zeigler; Ishoey, Thomas; Novotny, Mark A.; McLean, Jeffrey S.; Lasken, Roger S.; Williamson, Shannon J.

    2011-01-01

    Whole genome amplification and sequencing of single microbial cells has significantly influenced genomics and microbial ecology by facilitating direct recovery of reference genome data. However, viral genomics continues to suffer due to difficulties related to the isolation and characterization of uncultivated viruses. We report here on a new approach called ‘Single Virus Genomics’, which enabled the isolation and complete genome sequencing of the first single virus particle. A mixed assemblage comprised of two known viruses; E. coli bacteriophages lambda and T4, were sorted using flow cytometric methods and subsequently immobilized in an agarose matrix. Genome amplification was then achieved in situ via multiple displacement amplification (MDA). The complete lambda phage genome was recovered with an average depth of coverage of approximately 437X. The isolation and genome sequencing of uncultivated viruses using Single Virus Genomics approaches will enable researchers to address questions about viral diversity, evolution, adaptation and ecology that were previously unattainable. PMID:21436882

  20. Continuous exposure to infectious pancreatic necrosis virus during early life stages of rainbow trout, Oncorhynchus mykiss(Walbaum)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rainbow trout (Oncorhynchus mykiss, Walbaum) were exposed continuously to infectious pancreatic necrosis virus (IPNV) at 0, 10, 1,000, or 100,000 pfu/L of water to estimate the effects of chronic IPNV exposure on early life stages. Fish density averaged 35 fish/L or 140 fish/L, with a tank flow rat...

  1. Beyond knockout rats

    PubMed Central

    Huang, Guanyi; Tong, Chang; Kumbhani, Dhruv S; Ashton, Charles; Yan, Hexin

    2011-01-01

    The ability to “knockout” specific genes in mice via embryonic stem (ES) cell-based gene-targeting technology has significantly enriched our understanding of gene function in normal and disease phenotypes. Improvements on this original strategy have been developed to enable the manipulation of genomes in a more sophisticated fashion with unprecedented precision. The rat is the model of choice in many areas of scientific investigation despite the lack of rat genetic toolboxes. Most recent advances of zinc finger nucleases (ZFNs) and rat ES cells are diminishing the gap between rat and mouse with respect to reverse genetic approaches. Importantly, the establishment of rat ES cell-based gene targeting technology, in combination with the unique advantages of using rats, provides new, exciting opportunities to create animal models that mimic human diseases more faithfully. We hereby report our recent results concerning finer genetic modifications in the rat, and propose their potential applications in addressing biological questions. PMID:21383544

  2. Detection of sweet potato viruses in Yunnan and genetic diversity analysis of the common viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two hundred seventy-nine samples with virus-like symptoms collected from 16 regions in Yunnan Province were tested by RT-PCR/PCR using virus-specific primers for 8 sweet potato viruses. Six viruses, Sweet potato chlorotic fleck virus (SPCFV), Sweet Potato feathery mottle virus (SPFMV), Sweet potato ...

  3. Discrete virus infection model of hepatitis B virus.

    PubMed

    Zhang, Pengfei; Min, Lequan; Pian, Jianwei

    2015-01-01

    In 1996 Nowak and his colleagues proposed a differential equation virus infection model, which has been widely applied in the study for the dynamics of hepatitis B virus (HBV) infection. Biological dynamics may be described more practically by discrete events rather than continuous ones. Using discrete systems to describe biological dynamics should be reasonable. Based on one revised Nowak et al's virus infection model, this study introduces a discrete virus infection model (DVIM). Two equilibriums of this model, E1 and E2, represents infection free and infection persistent, respectively. Similar to the case of the basic virus infection model, this study deduces a basic virus reproductive number R0 independing on the number of total cells of an infected target organ. A proposed theorem proves that if the basic virus reproductive number R0<1 then the virus free equilibrium E1 is locally stable. The DVIM is more reasonable than an abstract discrete susceptible-infected-recovered model (SIRS) whose basic virus reproductive number R0 is relevant to the number of total cells of the infected target organ. As an application, this study models the clinic HBV DNA data of a patient who was accepted via anti-HBV infection therapy with drug lamivudine. The results show that the numerical simulation is good in agreement with the clinic data.

  4. Effects of long-term administration of cancer-promoting substances on oral subepithelial mast cells in the rat.

    PubMed

    Sand, L; Hilliges, M; Larsson, P A; Wallstrom, M; Hirsch, J M

    2002-01-01

    The role of oral subepithelial mast cells in the defence against tumours is a matter of controversy. The effect of established and suggested carcinogens, such as the carcinogen 4-nitroquinoline-N-oxide (4-NQO) and Herpes simplex virus type 1 (HSV-1), in combination with oral snuff on lower lip subepithelial mast cells (MC) was studied in rats. The rats were exposed to prolonged use of oral snuff. The test substances were administered in a surgically created canal in the lower lip of the rats. There were 15 rats in each test group and 10 rats in the control group. The amount of countable subepithelial mast cells decreased significantly when the rat oral mucosa was exposed to the oral carcinogen 4-NQO but the effect of oral snuff and HSV-1 infection was weak. Our findings suggest that mast cells play a role in immunological cell defence against chemical carcinogens. Further studies are needed to clarify the mechanisms. PMID:12529973

  5. Hetdex: Virus Instrument

    NASA Astrophysics Data System (ADS)

    Lee, Hanshin; Hill, G. J.; DePoy, D. L.; Tuttle, S.; Marshall, J. L.; Vattiat, B. L.; Prochaska, T.; Chonis, T. S.; Allen, R.; HETDEX Collaboration

    2012-01-01

    The Visible Integral-field-unit Replicable Unit Spectrograph (VIRUS) instrument is made up of 150+ individually compact and identical spectrographs, each fed by a fiber integral-field unit. The instrument provides integral field spectroscopy at wavelengths between 350nm and 550nm of over 33,600 spatial elements per observation, each 1.8 sq. arcsec on the sky, at R 700. The instrument will be fed by a new wide-field corrector (WFC) of the Hobby-Eberly Telescope (HET) with increased science field of view as large as 22arcmin diameter and telescope aperture of 10m. This will enable the HETDEX, a large area blind survey of Lyman-alpha emitting galaxies at redshift z < 3.5. The status of VIRUS instrument construction is summarized.

  6. Mechanisms of Virus Assembly

    PubMed Central

    Perlmutter, Jason D.; Hagan, Michael F.

    2015-01-01

    Viruses are nanoscale entities containing a nucleic acid genome encased in a protein shell called a capsid, and in some cases surrounded by a lipid bilayer membrane. This review summarizes the physics that govern the processes by which capsids assembles within their host cells and in vitro. We describe the thermodynamics and kinetics for assembly of protein subunits into icosahedral capsid shells, and how these are modified in cases where the capsid assembles around a nucleic acid or on a lipid bilayer. We present experimental and theoretical techniques that have been used to characterize capsid assembly, and we highlight aspects of virus assembly which are likely to receive significant attention in the near future. PMID:25532951

  7. The encephalomyocarditis virus

    PubMed Central

    Carocci, Margot; Bakkali-Kassimi, Labib

    2012-01-01

    The encephalomyocarditis virus (EMCV) is a small non-enveloped single-strand RNA virus, the causative agent of not only myocarditis and encephalitis, but also neurological diseases, reproductive disorders and diabetes in many mammalian species. EMCV pathogenesis appears to be viral strain- and host-specific, and a better understanding of EMCV virulence factors is increasingly required. Indeed, EMCV is often used as a model for diabetes and viral myocarditis, and is also widely used in immunology as a double-stranded RNA stimulus in the study of Toll-like as well as cytosolic receptors. However, EMCV virulence and properties have often been neglected. Moreover, EMCV is able to infect humans albeit with a low morbidity. Progress on xenografts, such as pig heart transplantation in humans, has raised safety concerns that need to be explored. In this review we will highlight the biology of EMCV and all known and potential virulence factors. PMID:22722247

  8. Cytomegalovirus: the stealth virus.

    PubMed

    Robinson, Sharon

    2016-05-01

    Cytomegalovirus (CMV) is an infection, part of the herpes family of viruses which, if contracted during pregnancy, cancause devastating effects on the newborn baby. This article is written by the trustee of a volunteer-based charity, mostly run by mothers of CMV children, who are striving to raise awareness of this infection, which is more common than Down's syndrome, listeria and toxoplasmosis, and is theprimary preventable cause of childhood hearing loss.

  9. VIRUS instrument collimator assembly

    NASA Astrophysics Data System (ADS)

    Marshall, Jennifer L.; DePoy, Darren L.; Prochaska, Travis; Allen, Richard D.; Williams, Patrick; Rheault, Jean-Philippe; Li, Ting; Nagasawa, Daniel Q.; Akers, Christopher; Baker, David; Boster, Emily; Campbell, Caitlin; Cook, Erika; Elder, Alison; Gary, Alex; Glover, Joseph; James, Michael; Martin, Emily; Meador, Will; Mondrik, Nicholas; Rodriguez-Patino, Marisela; Villanueva, Steven; Hill, Gary J.; Tuttle, Sarah; Vattiat, Brian; Lee, Hanshin; Chonis, Taylor S.; Dalton, Gavin B.; Tacon, Mike

    2014-07-01

    The Visual Integral-Field Replicable Unit Spectrograph (VIRUS) instrument is a baseline array 150 identical fiber fed optical spectrographs designed to support observations for the Hobby-Eberly Telescope Dark Energy Experiment (HETDEX). The collimator subassemblies of the instrument have been assembled in a production line and are now complete. Here we review the design choices and assembly practices used to produce a suite of identical low-cost spectrographs in a timely fashion using primarily unskilled labor.

  10. Hepatitis C Virus.

    PubMed

    Kim, Arthur

    2016-09-01

    This issue provides a clinical overview of hepatitis C virus, focusing on transmission, prevention, screening, diagnosis, evaluation, and treatment. The content of In the Clinic is drawn from the clinical information and education resources of the American College of Physicians (ACP), including MKSAP (Medical Knowledge and Self-Assessment Program). Annals of Internal Medicine editors develop In the Clinic in collaboration with the ACP's Medical Education and Publishing divisions and with the assistance of additional science writers and physician writers. PMID:27595226

  11. Physical Studies on Pox Viruses

    PubMed Central

    McCrea, J. F.; Preiss, John W.; O'Loughlin, Jean

    1960-01-01

    Vaccinia virus was irradiated in vacuo with low-voltage electrons of restricted ranges. It was found that the pock-forming ability of the virus was not decreased after bombardment with electrons penetrating 100 A beneath the virus surface. There was very slight reduction in titer with large doses of electrons penetrating 330 A, but a sudden marked drop in infectivity occurred after exposure to electrons penetrating 500 to 700 A. Electrons of higher energies, including those capable of penetrating the virus particle completely, did not produce significant further fall in infectivity titer. It is concluded that a highly radiation-sensitive unit essential for pock formation is situated 500 to 700 A beneath the surface of the virus particle, possibly in the form of a shell. The relation of this finding to the known structure of the virus and to other radiation data on the dimensions of the infectious unit is discussed. PMID:13773839

  12. Proteorhodopsin genes in giant viruses.

    PubMed

    Yutin, Natalya; Koonin, Eugene V

    2012-01-01

    Viruses with large genomes encode numerous proteins that do not directly participate in virus biogenesis but rather modify key functional systems of infected cells. We report that a distinct group of giant viruses infecting unicellular eukaryotes that includes Organic Lake Phycodnaviruses and Phaeocystis globosa virus encode predicted proteorhodopsins that have not been previously detected in viruses. Search of metagenomic sequence data shows that putative viral proteorhodopsins are extremely abundant in marine environments. Phylogenetic analysis suggests that giant viruses acquired proteorhodopsins via horizontal gene transfer from proteorhodopsin-encoding protists although the actual donor(s) could not be presently identified. The pattern of conservation of the predicted functionally important amino acid residues suggests that viral proteorhodopsin homologs function as sensory rhodopsins. We hypothesize that viral rhodopsins modulate light-dependent signaling, in particular phototaxis, in infected protists.

  13. Principles of Virus Structural Organization

    PubMed Central

    Prasad, B.V. Venkataram; Schmid, Michael F

    2013-01-01

    Viruses, the molecular nanomachines infecting hosts ranging from prokaryotes to eukaryotes, come in different sizes, shapes and symmetries. Questions such as what principles govern their structural organization, what factors guide their assembly, how these viruses integrate multifarious functions into one unique structure have enamored researchers for years. In the last five decades, following Caspar and Klug's elegant conceptualization of how viruses are constructed, high resolution structural studies using X-ray crystallography and more recently cryo-EM techniques have provided a wealth of information on structures of variety of viruses. These studies have significantly furthered our understanding of the principles that underlie structural organization in viruses. Such an understanding has practical impact in providing a rational basis for the design and development of antiviral strategies. In this chapter, we review principles underlying capsid formation in a variety of viruses, emphasizing the recent developments along with some historical perspective. PMID:22297509

  14. Ebola Virus Disease

    PubMed Central

    Kourtis, Athena P.; Appelgren, Kristie; Chevalier, Michelle S.; McElroy, Anita

    2015-01-01

    Ebola virus is one of the most deadly pathogens known to infect humans. The current Ebola outbreak in West Africa is unprecedented in magnitude and duration and, as of November 30, 2014, shows no signs of abating. For the first time, cases of Ebola virus disease have been diagnosed in the US, originating from patients who traveled during the incubation period. The outbreak has generated worldwide concern. It is clear that U.S. physicians need to be aware of this disease, know when to consider Ebola and how to care for the patient as well as protect themselves. Children comprise a small percentage of all cases globally, likely because of their lower risk of exposure given social and cultural practices. Limited evidence is available on pediatric disease course and prognosis. In this article, we present an overview of the pathogen, its epidemiology and transmission, clinical and laboratory manifestations, treatment and infection control procedures, with an emphasis on what is known about Ebola virus disease in the pediatric population. PMID:25831417

  15. Detection of dengue virus.

    PubMed

    Tripathi, Nagesh K; Shrivastava, Ambuj; Dash, Paban K; Jana, Asha M

    2011-01-01

    Global incidence of dengue has increased considerably over the past decade. Dengue fever (DF) is a self-limiting disease; however, dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS) are fatal. Since there is no therapy and vaccine against dengue, timely diagnosis is therefore necessary for patient management. Laboratory diagnosis is carried out by virus isolation, demonstration of viral antigen, presence of viral nucleic acid, and antibodies. Further, recombinant dengue envelope protein can be used to detect specific antibodies, both IgG and IgM against all four serotypes of virus using an E. coli vector. The purified protein can then be used for detection of dengue specific IgG or IgM antibodies in patient serum with higher sensitivity and specificity, than that of traditional assays. Molecular detection can be accomplished by a one-step, single-tube, rapid, multiplex, RT-PCR for serotype determination. Despite many advantages of the modern techniques, isolation of virus is still considered as "gold-standard" in dengue diagnosis.

  16. Parainfluenza Virus Infection.

    PubMed

    Branche, Angela R; Falsey, Ann R

    2016-08-01

    Human parainfluenza viruses (HPIVs) are single-stranded, enveloped RNA viruses of the Paramyoviridaie family. There are four serotypes which cause respiratory illnesses in children and adults. HPIVs bind and replicate in the ciliated epithelial cells of the upper and lower respiratory tract and the extent of the infection correlates with the location involved. Seasonal HPIV epidemics result in a significant burden of disease in children and account for 40% of pediatric hospitalizations for lower respiratory tract illnesses (LRTIs) and 75% of croup cases. Parainfluenza viruses are associated with a wide spectrum of illnesses which include otitis media, pharyngitis, conjunctivitis, croup, tracheobronchitis, and pneumonia. Uncommon respiratory manifestations include apnea, bradycardia, parotitis, and respiratory distress syndrome and rarely disseminated infection. Immunity resulting from disease in childhood is incomplete and reinfection with HPIV accounts for 15% of respiratory illnesses in adults. Severe disease and fatal pneumonia may occur in elderly and immunocompromised adults. HPIV pneumonia in recipients of hematopoietic stem cell transplant (HSCT) is associated with 50% acute mortality and 75% mortality at 6 months. Though sensitive molecular diagnostics are available to rapidly diagnose HPIV infection, effective antiviral therapies are not available. Currently, treatment for HPIV infection is supportive with the exception of croup where the use of corticosteroids has been found to be beneficial. Several novel drugs including DAS181 appear promising in efforts to treat severe disease in immunocompromised patients, and vaccines to decrease the burden of disease in young children are in development. PMID:27486735

  17. Detection of mouse hepatitis virus infection by assay of anti-liver autoantibodies.

    PubMed

    Mathieu, Patricia A; Gómez, Karina A; Coutelier, Jean-Paul; Retegui, Lilia A

    2002-12-01

    The observation that mice infected with mouse hepatitis virus (MHV) develop autoantibodies directed mainly to liver fumarylacetoacetate hydrolase (FAH) enabled the development of an ELISA applicable to the detection of MHV-infection. The method, based on the titration of antibodies to semipurified FAH from rat liver, is easy, economical, and does not require the isolation of viral proteins from large MHV stocks. Furthermore, since sera from mice immunized with a purified fraction of the rat liver enzyme do react with its homologous protein, this antiserum can be used as a positive control avoiding the manipulation of samples from MHV-infected animals.

  18. Respiratory syncytial virus fusion inhibitors. Part 4: optimization for oral bioavailability.

    PubMed

    Yu, Kuo-Long; Sin, Ny; Civiello, Rita L; Wang, X Alan; Combrink, Keith D; Gulgeze, H Belgin; Venables, Brian L; Wright, J J Kim; Dalterio, Richard A; Zadjura, Lisa; Marino, Anthony; Dando, Sandra; D'Arienzo, Celia; Kadow, Kathleen F; Cianci, Christopher W; Li, Zhufang; Clarke, Junius; Genovesi, Eugene V; Medina, Ivette; Lamb, Lucinda; Colonno, Richard J; Yang, Zheng; Krystal, Mark; Meanwell, Nicholas A

    2007-02-15

    A series of benzimidazole-based inhibitors of respiratory syncytial virus (RSV) fusion were optimized for antiviral potency, membrane permeability and metabolic stability in human liver microsomes. 1-Cyclopropyl-1,3-dihydro-3-[[1-(4-hydroxybutyl)-1H-benzimidazol-2-yl]methyl]-2H-imidazo[4,5-c]pyridin-2-one (6m, BMS-433771) was identified as a potent RSV inhibitor demonstrating good bioavailability in the mouse, rat, dog and cynomolgus monkey that demonstrated antiviral activity in the BALB/c and cotton rat models of infection following oral administration.

  19. Photoreactivation of a Cytoplasmic Virus

    PubMed Central

    Pfefferkorn, E. R.; Boyle, Mary K.

    1972-01-01

    Ultraviolet light-inactivated frog virus 3 is efficiently photoreactivated by chick embryo cells. A cellular enzyme is presumably responsible for this repair of viral deoxyribonucleic acid, for the phenomenon is insensitive to an inhibitor of protein synthesis and is not seen in mammalian cells that are known to lack photoreactivating enzyme. Since frog virus 3 is a cytoplasmic virus, functionally significant amounts of photoreactivating enzyme are probably present in the cytoplasm of chick embryo cells. PMID:5062749

  20. [Hemorrhagic fever viruses in Madagascar].

    PubMed

    Fontenille, D; Mathiot, C; Coulanges, P

    1988-01-01

    The authors remind, what are the viral haemorrhagic fevers, and explain the situation in Madagascar. The viruses of Crimée-Congo haemorrhagic fever, Rift valley fever and haemorrhagic fever with renal syndrome are present in Madagascar. There is no real proof about the presence of Dengue viruses. The yellow fever viruses have never been stown off. It seems that there was not diagnosed outbreak of haemorrhagic fever, since the beginning of our century.

  1. Viruses manipulate the marine environment.

    PubMed

    Rohwer, Forest; Thurber, Rebecca Vega

    2009-05-14

    Marine viruses affect Bacteria, Archaea and eukaryotic organisms and are major components of the marine food web. Most studies have focused on their role as predators and parasites, but many of the interactions between marine viruses and their hosts are much more complicated. A series of recent studies has shown that viruses have the ability to manipulate the life histories and evolution of their hosts in remarkable ways, challenging our understanding of this almost invisible world.

  2. Introducing Virological Concepts Using an Insect Virus.

    ERIC Educational Resources Information Center

    Sheppard, Roger F.

    1980-01-01

    A technique is presented which utilizes wax moth larvae in a laboratory investigation of an insect virus. Describes how an insect virus can be used to introduce undergraduate biology students to laboratory work on viruses and several virological concepts. (SA)

  3. Selecting Viruses for the Seasonal Influenza Vaccine

    MedlinePlus

    ... which viruses are selected for use in vaccine production? The influenza viruses in the seasonal flu vaccine ... to get a good vaccine virus for vaccine production? There are a number of factors that can ...

  4. Variant (Swine Origin) Influenza Viruses in Humans

    MedlinePlus

    ... What's this? Submit Button Past Newsletters Variant Influenza Viruses: Background and CDC Risk Assessment and Reporting Language: ... Background CDC Assessment Reporting Background On Variant Influenza Viruses Swine flu viruses do not normally infect humans. ...

  5. Dengue Virus May Bolster Zika's Attack

    MedlinePlus

    ... dengue fever virus may increase the severity of Zika virus, a new study says. Early stage laboratory findings ... Services, or federal policy. More Health News on: Zika Virus Recent Health News Related MedlinePlus Health Topics Dengue ...

  6. Human Immunodeficiency Virus (HIV) Primary Infection

    MedlinePlus

    ... rashes clinical tools newsletter | contact Share | Human Immunodeficiency Virus (HIV) Primary Infection Information for adults A A ... weeks following exposure to HIV (the human immunodeficiency virus). Chronic infection with this virus can cause AIDS ( ...

  7. Emergence of influenza A viruses.

    PubMed Central

    Webby, R J; Webster, R G

    2001-01-01

    Pandemic influenza in humans is a zoonotic disease caused by the transfer of influenza A viruses or virus gene segments from animal reservoirs. Influenza A viruses have been isolated from avian and mammalian hosts, although the primary reservoirs are the aquatic bird populations of the world. In the aquatic birds, influenza is asymptomatic, and the viruses are in evolutionary stasis. The aquatic bird viruses do not replicate well in humans, and these viruses need to reassort or adapt in an intermediate host before they emerge in human populations. Pigs can serve as a host for avian and human viruses and are logical candidates for the role of intermediate host. The transmission of avian H5N1 and H9N2 viruses directly to humans during the late 1990s showed that land-based poultry also can serve between aquatic birds and humans as intermediate hosts of influenza viruses. That these transmission events took place in Hong Kong and China adds further support to the hypothesis that Asia is an epicentre for influenza and stresses the importance of surveillance of pigs and live-bird markets in this area. PMID:11779380

  8. Nuclear entry of DNA viruses

    PubMed Central

    Fay, Nikta; Panté, Nelly

    2015-01-01

    DNA viruses undertake their replication within the cell nucleus, and therefore they must first deliver their genome into the nucleus of their host cells. Thus, trafficking across the nuclear envelope is at the basis of DNA virus infections. Nuclear transport of molecules with diameters up to 39 nm is a tightly regulated process that occurs through the nuclear pore complex (NPC). Due to the enormous diversity of virus size and structure, each virus has developed its own strategy for entering the nucleus of their host cells, with no two strategies alike. For example, baculoviruses target their DNA-containing capsid to the NPC and subsequently enter the nucleus intact, while the hepatitis B virus capsid crosses the NPC but disassembles at the nuclear side of the NPC. For other viruses such as herpes simplex virus and adenovirus, although both dock at the NPC, they have each developed a distinct mechanism for the subsequent delivery of their genome into the nucleus. Remarkably, other DNA viruses, such as parvoviruses and human papillomaviruses, access the nucleus through an NPC-independent mechanism. This review discusses our current understanding of the mechanisms used by DNA viruses to deliver their genome into the nucleus, and further presents the experimental evidence for such mechanisms. PMID:26029198

  9. Review: influenza virus in pigs.

    PubMed

    Crisci, Elisa; Mussá, Tufária; Fraile, Lorenzo; Montoya, Maria

    2013-10-01

    Influenza virus disease still remains one of the major threats to human health, involving a wide range of animal species and pigs play an important role in influenza ecology. Pigs were labeled as "mixing vessels" since they are susceptible to infection with avian, human and swine influenza viruses and genetic reassortment between these viruses can occur. After the H1N1 influenza pandemic of 2009 with a swine origin virus, the most recent research in "influenzology" is directed at improving knowledge of porcine influenza virus infection. This tendency is probably due to the fact that domestic pigs are closely related to humans and represent an excellent animal model to study various microbial infectious diseases. In spite of the role of the pig in influenza virus ecology, swine immune responses against influenza viruses are not fully understood. Considering these premises, the aim of this review is to focus on the in vitro studies performed with porcine cells and influenza virus and on the immune responses of pigs against human, avian and swine influenza viruses in vivo. The increased acceptance of pigs as suitable and valuable models in the scientific community may stimulate the development of new tools to assess porcine immune responses, paving the way for their consideration as the future "gold standard" large-animal model in immunology.

  10. RECOVIR Software for Identifying Viruses

    NASA Technical Reports Server (NTRS)

    Chakravarty, Sugoto; Fox, George E.; Zhu, Dianhui

    2013-01-01

    Most single-stranded RNA (ssRNA) viruses mutate rapidly to generate a large number of strains with highly divergent capsid sequences. Determining the capsid residues or nucleotides that uniquely characterize these strains is critical in understanding the strain diversity of these viruses. RECOVIR (an acronym for "recognize viruses") software predicts the strains of some ssRNA viruses from their limited sequence data. Novel phylogenetic-tree-based databases of protein or nucleic acid residues that uniquely characterize these virus strains are created. Strains of input virus sequences (partial or complete) are predicted through residue-wise comparisons with the databases. RECOVIR uses unique characterizing residues to identify automatically strains of partial or complete capsid sequences of picorna and caliciviruses, two of the most highly diverse ssRNA virus families. Partition-wise comparisons of the database residues with the corresponding residues of more than 300 complete and partial sequences of these viruses resulted in correct strain identification for all of these sequences. This study shows the feasibility of creating databases of hitherto unknown residues uniquely characterizing the capsid sequences of two of the most highly divergent ssRNA virus families. These databases enable automated strain identification from partial or complete capsid sequences of these human and animal pathogens.

  11. Semliki Forest virus and Sindbis virus, but not vaccinia virus, require glycolysis for optimal replication.

    PubMed

    Findlay, James S; Ulaeto, David

    2015-09-01

    Viruses are obligate intracellular pathogens which rely on the cell's machinery to produce the energy and macromolecules required for replication. Infection is associated with a modified metabolic profile and one pathway which can be modified is glycolysis. In this study, we investigated if the glycolysis pathway is required for alphavirus replication. Pre-treatment of Vero cells with three different glycolysis inhibitors (2-deoxyglucose, lonidamine and oxamate) resulted in a significant reduction (but not abrogation) of Semliki Forest virus and Sindbis virus replication, but not of the unrelated virus, vaccinia virus. Reduced virus yield was not associated with any significant cytotoxic effect and delayed treatment up to 3 h post-infection still resulted in a significant reduction. This suggested that glycolysis is required for optimal replication of alphaviruses by supporting post-entry life cycle steps.

  12. Structure of Flexible Filamentous Plant Viruses

    SciTech Connect

    Kendall, Amy; McDonald, Michele; Bian, Wen; Bowles, Timothy; Baumgarten, Sarah C.; Shi, Jian; Stewart, Phoebe L.; Bullitt, Esther; Gore, David; Irving, Thomas C.; Havens, Wendy M.; Ghabrial, Said A.; Wall, Joseph S.; Stubbs, Gerald

    2008-10-23

    Flexible filamentous viruses make up a large fraction of the known plant viruses, but in comparison with those of other viruses, very little is known about their structures. We have used fiber diffraction, cryo-electron microscopy, and scanning transmission electron microscopy to determine the symmetry of a potyvirus, soybean mosaic virus; to confirm the symmetry of a potexvirus, potato virus X; and to determine the low-resolution structures of both viruses. We conclude that these viruses and, by implication, most or all flexible filamentous plant viruses share a common coat protein fold and helical symmetry, with slightly less than 9 subunits per helical turn.

  13. Computer virus information update CIAC-2301

    SciTech Connect

    Orvis, W.J.

    1994-01-15

    While CIAC periodically issues bulletins about specific computer viruses, these bulletins do not cover all the computer viruses that affect desktop computers. The purpose of this document is to identify most of the known viruses for the MS-DOS and Macintosh platforms and give an overview of the effects of each virus. The authors also include information on some windows, Atari, and Amiga viruses. This document is revised periodically as new virus information becomes available. This document replaces all earlier versions of the CIAC Computer virus Information Update. The date on the front cover indicates date on which the information in this document was extracted from CIAC`s Virus database.

  14. Zika virus: epidemiology, clinical features and host-virus interactions.

    PubMed

    Hamel, Rodolphe; Liégeois, Florian; Wichit, Sineewanlaya; Pompon, Julien; Diop, Fodé; Talignani, Loïc; Thomas, Frédéric; Desprès, Philippe; Yssel, Hans; Missé, Dorothée

    2016-01-01

    Very recently, Zika virus (ZIKV) has gained a medical importance following the large-scale epidemics in South Pacific and Latin America. This paper reviews information on the epidemiology and clinical features of Zika disease with a particular emphasis on the host-virus interactions that contribute to the pathogenicity of ZIKV in humans.

  15. Anjozorobe hantavirus, a new genetic variant of Thailand virus detected in rodents from Madagascar.

    PubMed

    Reynes, Jean-Marc; Razafindralambo, Nadia Kaloina; Lacoste, Vincent; Olive, Marie-Marie; Barivelo, Tony Andrianaivo; Soarimalala, Voahangy; Heraud, Jean-Michel; Lavergne, Anne

    2014-03-01

    Until now, there was only serological evidence that hantaviruses were circulating in rodents and infecting humans from Madagascar. To assess the presence of a hantavirus on the island, between October, 2008, and March, 2010, we sampled 585 rodents belonging to seven species in the Anjozorobe-Angavo forest corridor, 70 km north from the capital city Antananarivo. A hantavirus was detected from organs of the ubiquist roof rat (Rattus rattus) and of the endemic Major's tufted-tailed rat (Eliurus majori). Amazingly, sequence analysis of the S (small), M (medium), and L (large) coding DNA sequence of this virus showed that the Anjozorobe strain (proposed name) was a new genetic variant of Thailand virus (THAIV) that comprises other variants found in Southeast Asia. Because THAIV is suspected of causing hemorrhagic fever with renal syndrome in humans, ongoing studies are addressing the risk of infection by this new variant in the Malagasy population.

  16. Anjozorobe Hantavirus, a New Genetic Variant of Thailand Virus Detected in Rodents from Madagascar

    PubMed Central

    Razafindralambo, Nadia Kaloina; Lacoste, Vincent; Olive, Marie-Marie; Barivelo, Tony Andrianaivo; Soarimalala, Voahangy; Heraud, Jean-Michel; Lavergne, Anne

    2014-01-01

    Abstract Until now, there was only serological evidence that hantaviruses were circulating in rodents and infecting humans from Madagascar. To assess the presence of a hantavirus on the island, between October, 2008, and March, 2010, we sampled 585 rodents belonging to seven species in the Anjozorobe-Angavo forest corridor, 70 km north from the capital city Antananarivo. A hantavirus was detected from organs of the ubiquist roof rat (Rattus rattus) and of the endemic Major's tufted-tailed rat (Eliurus majori). Amazingly, sequence analysis of the S (small), M (medium), and L (large) coding DNA sequence of this virus showed that the Anjozorobe strain (proposed name) was a new genetic variant of Thailand virus (THAIV) that comprises other variants found in Southeast Asia. Because THAIV is suspected of causing hemorrhagic fever with renal syndrome in humans, ongoing studies are addressing the risk of infection by this new variant in the Malagasy population. PMID:24575755

  17. Uukuniemi Virus as a Tick-Borne Virus Model

    PubMed Central

    Mazelier, Magalie; Rouxel, Ronan Nicolas; Zumstein, Michael; Mancini, Roberta; Bell-Sakyi, Lesley

    2016-01-01

    ABSTRACT In the last decade, novel tick-borne pathogenic phleboviruses in the family Bunyaviridae, all closely related to Uukuniemi virus (UUKV), have emerged on different continents. To reproduce the tick-mammal switch in vitro, we first established a reverse genetics system to rescue UUKV with a genome close to that of the authentic virus isolated from the Ixodes ricinus tick reservoir. The IRE/CTVM19 and IRE/CTVM20 cell lines, both derived from I. ricinus, were susceptible to the virus rescued from plasmid DNAs and supported production of the virus over many weeks, indicating that infection was persistent. The glycoprotein GC was mainly highly mannosylated on tick cell-derived viral progeny. The second envelope viral protein, GN, carried mostly N-glycans not recognized by the classical glycosidases peptide-N-glycosidase F (PNGase F) and endoglycosidase H (Endo H). Treatment with β-mercaptoethanol did not impact the apparent molecular weight of GN. On viruses originating from mammalian BHK-21 cells, GN glycosylations were exclusively sensitive to PNGase F, and the electrophoretic mobility of the protein was substantially slower after the reduction of disulfide bonds. Furthermore, the amount of viral nucleoprotein per focus forming unit differed markedly whether viruses were produced in tick or BHK-21 cells, suggesting a higher infectivity for tick cell-derived viruses. Together, our results indicate that UUKV particles derived from vector tick cells have glycosylation and structural specificities that may influence the initial infection in mammalian hosts. This study also highlights the importance of working with viruses originating from arthropod vector cells in investigations of the cell biology of arbovirus transmission and entry into mammalian hosts. IMPORTANCE Tick-borne phleboviruses represent a growing threat to humans globally. Although ticks are important vectors of infectious emerging diseases, previous studies have mainly involved virus stocks

  18. Identification of a sarcoma virus-coded phosphoprotein in nonproducer cells transformed by Kirsten or Harvey murine sarcoma virus.

    PubMed

    Shih, T Y; Weeks, M O; Young, H A; Scholnick, E M

    1979-07-15

    A similar protein of 21,000 MW (p21) coded for by Harvey or Kirsten murine sarcoma virus has been identified in nonproducer cells transformed by these two viruses. Antisera prepared from rats bearing tumors induced by syngeneic transplantation of NRK cells transformed by Harvey murine sarcoma virus (Ha-MuSV) specifically precipitated the Ha-MuSV p21 from a nonproducer Balb/c mouse cell and a nonproducer dog cell transformed by Ha-MuSV. The same antisera also precipitated a similar protein, Ki-MuSV p21, from a nonproducer mink cell transformed by Kirsten murine sarcoma virus (Ki-MuSV). Both the p21 of Ha-MuSV and of Ki-MuSV are phosphoproteins. Previous studies have reported a virus-specific p21 polypeptide from translation of Ha-MuSV RNA in cell-free protein synthesis systems (W. P. Parks and E. M. Scolnick, 1977, J. Virol. 22, 711-719; T. Y. Shih, D. R. Williams, M. O. Weeks, J. M. Maryak, W. C. Vass, and E. M. Scolnick, 1978, J. Virol 27, 45-55). This p21 protein was specifically precipitated by the same anti-tumor sera. Similarly, a p21 polypeptide translated from Ki-MuSV RNA was also specifically precipitated by the antitumor sera. Therefore, it is concluded that the p21 of Ha-MuSV and Ki-MuSV are homologous proteins coded for bv homologous sequences found in the recombinant genomes of Ha-MuSV and Ki-MuSV.

  19. Detection of zoonotic pathogens and characterization of novel viruses carried by commensal Rattus norvegicus in New York City.

    PubMed

    Firth, Cadhla; Bhat, Meera; Firth, Matthew A; Williams, Simon H; Frye, Matthew J; Simmonds, Peter; Conte, Juliette M; Ng, James; Garcia, Joel; Bhuva, Nishit P; Lee, Bohyun; Che, Xiaoyu; Quan, Phenix-Lan; Lipkin, W Ian

    2014-10-14

    Norway rats (Rattus norvegicus) are globally distributed and concentrate in urban environments, where they live and feed in closer proximity to human populations than most other mammals. Despite the potential role of rats as reservoirs of zoonotic diseases, the microbial diversity present in urban rat populations remains unexplored. In this study, we used targeted molecular assays to detect known bacterial, viral, and protozoan human pathogens and unbiased high-throughput sequencing to identify novel viruses related to agents of human disease in commensal Norway rats in New York City. We found that these rats are infected with bacterial pathogens known to cause acute or mild gastroenteritis in people, including atypical enteropathogenic Escherichia coli, Clostridium difficile, and Salmonella enterica, as well as infectious agents that have been associated with undifferentiated febrile illnesses, including Bartonella spp., Streptobacillus moniliformis, Leptospira interrogans, and Seoul hantavirus. We also identified a wide range of known and novel viruses from groups that contain important human pathogens, including sapoviruses, cardioviruses, kobuviruses, parechoviruses, rotaviruses, and hepaciviruses. The two novel hepaciviruses discovered in this study replicate in the liver of Norway rats and may have utility in establishing a small animal model of human hepatitis C virus infection. The results of this study demonstrate the diversity of microbes carried by commensal rodent species and highlight the need for improved pathogen surveillance and disease monitoring in urban environments. Importance: The observation that most emerging infectious diseases of humans originate in animal reservoirs has led to wide-scale microbial surveillance and discovery programs in wildlife, particularly in the developing world. Strikingly, less attention has been focused on commensal animals like rats, despite their abundance in urban centers and close proximity to human populations

  20. [Titration of antibodies to lymphocytic choriomeningitis virus by the method of indirect immunofluorescence].

    PubMed

    Sheĭnbergas, M M; Vorob'eva, Z N

    1975-01-01

    Antibody to lymphocytic choriomeningitis virus was determined by the indirect immunofluorescence test in immune sera of guinea pigs and immune ascitic fluids of rats and mice. Among 135 patients with aseptic meningitis serum antibody was found in 11 patients in titers of 1 : 64 to 1 : 128 and in the cerebro-spinal fluid of these patients in considerably lower titers. By the indirect immunofluorescence test antibody in maximum titers was found early after the appearance of meningeal symptoms.

  1. A bead-based multiplex assay for the detection of DNA viruses infecting laboratory rodents.

    PubMed

    Höfler, Daniela; Nicklas, Werner; Mauter, Petra; Pawlita, Michael; Schmitt, Markus

    2014-01-01

    The Federation of European Laboratory Animal Science Association (FELASA) recommends screening of laboratory rodents and biological materials for a broad variety of bacterial agents, viruses, and parasites. Methods commonly used to date for pathogen detection are neither cost-effective nor time- and animal-efficient or uniform. However, an infection even if silent alters experimental results through changing the animals' physiology and increases inter-individual variability. As a consequence higher numbers of animals and experiments are needed for valid and significant results. We developed a novel high-throughput multiplex assay, called rodent DNA virus finder (rDVF) for the simultaneous identification of 24 DNA viruses infecting mice and rats. We detected all 24 DNA viruses with high specificity and reproducibility. Detection limits for the different DNA viruses varied between 10 and 1000 copies per PCR. The validation of rDVF was done with DNA isolated from homogenised organs amplified by pathogen specific primers in one multiplex PCR. The biotinylated amplicons were detected via hybridisation to specific oligonucleotide probes coupled to spectrally distinct sets of fluorescent Luminex beads. In conclusion, rDVF may have the potential to replace conventional testing and may simplify and improve routine detection of DNA viruses infecting rodents.

  2. Relationship between RNA polymerase II and efficiency of vaccinia virus replication.

    PubMed Central

    Wilton, S; Dales, S

    1989-01-01

    It is clear from previous studies that host transcriptase or RNA polymerase II (pol II) has a role in poxvirus replication. To elucidate the participation of this enzyme further, in this study we examined several parameters related to pol II during the cycle of vaccinia virus infection in L-strain fibroblasts, HeLa cells, and L6H9 rat myoblasts. Nucleocytoplasmic transposition of pol II into virus factories and virions was assessed by immunofluorescence and immunoblotting by using anti-pol II immunoglobulin G. RNA polymerase activities were compared in nuclear extracts containing crude enzyme preparations. Rates of translation into cellular or viral polypeptides were ascertained by labeling with [35S]methionine. In L and HeLa cells, which produced vaccinia virus more abundantly, the rates of RNA polymerase and translation in controls and following infection were higher than in myoblasts. The data on synthesis and virus formation could be correlated with observations on transmigration of pol II, which was more efficient and complete in L and HeLa cells. The stimulus for pol II to leave the nucleus required the expression of both early and late viral functions. On the basis of current and past information, we suggest that mobilization of pol II depends on the efficiency of vaccina virus replication and furthermore that control over vaccinia virus production by the host is related to the content or availability (or both) of pol II in different cell types. Images PMID:2648021

  3. Recombinant measles virus incorporating heterologous viral membrane proteins for use as vaccines.

    PubMed

    Swett-Tapia, Cindy; Bogaert, Lies; de Jong, Pascal; van Hoek, Vladimir; Schouten, Theo; Damen, Irma; Spek, Dirk; Wanningen, Patrick; Radošević, Katarina; Widjojoatmodjo, Myra N; Zahn, Roland; Custers, Jerome; Roy, Soumitra

    2016-09-01

    Recombinant measles virus (rMV) vectors expressing heterologous viral membrane protein antigens are potentially useful as vaccines. Genes encoding the mumps virus haemagglutinin-neuraminidase (MuV-HN), the influenza virus haemagglutinin (Flu-HA) or the respiratory syncytial virus fusion (RSV-F) proteins were inserted into the genome of a live attenuated vaccine strain of measles virus. Additionally, in this case rMV with the MuV-HN or the influenza HA inserts, chimeric constructs were created that harboured the measles virus native haemagglutinin or fusion protein cytoplasmic domains. In all three cases, sucrose-gradient purified preparations of rMV were found to have incorporated the heterologous viral membrane protein on the viral membrane. The possible utility of rMV expressing RSV-F (rMV.RSV-F) as a vaccine was tested in a cotton rat challenge model. Vaccination with rMV.RSV-F efficiently induced neutralizing antibodies against RSV and protected animals from infection with RSV in the lungs. PMID:27311834

  4. Relationship between RNA polymerase II and efficiency of vaccinia virus replication

    SciTech Connect

    Wilton, S.; Dales, S.

    1989-04-01

    It is clear from previous studies that host transcriptase or RNA polymerase II (pol II) has a role in poxvirus replication. To elucidate the participation of this enzyme further, in this study the authors examined several parameters related to pol II during the cycle of vaccinia virus infection in L-strain fibroblasts, HeLa cells, and L/sub 6/H/sub 9/ rat myoblasts. Nucleocytoplasmic transposition of pol II into virus factories and virions was assessed by immunofluorescence and immunoblotting by using anti-pol II immunoglobulin G. RNA polymerase activities were compared in nuclear extracts containing cured enzyme preparations. Rates of translation into cellular or viral polypeptides were ascertained by labeling with (/sup 35/S)methionine. In L and HeLa cells, which produced vaccinia virus more abundantly, the rate of RNA polymerase and translation in controls and following infection were higher than in myoblasts. The data on synthesis and virus formation could be correlated with observations on transmigration of pol II, which was more efficient and complete in L and HeLa cells. The stimulus for pol II to leave the nucleus required the expression of both early and late viral functions. On the basis of current and past information, the authors suggest that mobilization of pol II depends on the efficiency of vaccinia virus replication and furthermore that control over vaccinia virus production by the host is related to the content or availability (or both) of pol II in different cell types.

  5. Virioplankton: Viruses in Aquatic Ecosystems†

    PubMed Central

    Wommack, K. Eric; Colwell, Rita R.

    2000-01-01

    The discovery that viruses may be the most abundant organisms in natural waters, surpassing the number of bacteria by an order of magnitude, has inspired a resurgence of interest in viruses in the aquatic environment. Surprisingly little was known of the interaction of viruses and their hosts in nature. In the decade since the reports of extraordinarily large virus populations were published, enumeration of viruses in aquatic environments has demonstrated that the virioplankton are dynamic components of the plankton, changing dramatically in number with geographical location and season. The evidence to date suggests that virioplankton communities are composed principally of bacteriophages and, to a lesser extent, eukaryotic algal viruses. The influence of viral infection and lysis on bacterial and phytoplankton host communities was measurable after new methods were developed and prior knowledge of bacteriophage biology was incorporated into concepts of parasite and host community interactions. The new methods have yielded data showing that viral infection can have a significant impact on bacteria and unicellular algae populations and supporting the hypothesis that viruses play a significant role in microbial food webs. Besides predation limiting bacteria and phytoplankton populations, the specific nature of virus-host interaction raises the intriguing possibility that viral infection influences the structure and diversity of aquatic microbial communities. Novel applications of molecular genetic techniques have provided good evidence that viral infection can significantly influence the composition and diversity of aquatic microbial communities. PMID:10704475

  6. Emerging tomato viruses in Florida

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Tomato spotted wilt virus (TSWV) causes crop losses worldwide. This tospovirus is well-known for disease epidemics in vegetable, ornamental and peanut crops in the southeastern U.S. Two other tospoviruses have recently emerged in south Florida. Groundnut ringspot virus (GRSV) was first detected in ...

  7. Tobacco ringspot virus in Rubus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Tobacco ringspot virus (TRSV) has a broad host range among woody and perennial plants and has been reported from blackberry but not from red or black raspberry. The virus has been detected in blackberry in the southeastern United States with a single report from blackberry in British Columbia, Cana...

  8. TOTAL CULTURABLE VIRUS QUANTAL ASSAY

    EPA Science Inventory

    This chapter describes a quantal method for assaying culturable human enteric viruses from water matrices. The assay differs from the plaque assay described in Chapter 10 (December 1987 Revision) in that it is based upon the direct microscopic viewing of cells for virus-induced ...

  9. Defining life: the virus viewpoint.

    PubMed

    Forterre, Patrick

    2010-04-01

    Are viruses alive? Until very recently, answering this question was often negative and viruses were not considered in discussions on the origin and definition of life. This situation is rapidly changing, following several discoveries that have modified our vision of viruses. It has been recognized that viruses have played (and still play) a major innovative role in the evolution of cellular organisms. New definitions of viruses have been proposed and their position in the universal tree of life is actively discussed. Viruses are no more confused with their virions, but can be viewed as complex living entities that transform the infected cell into a novel organism-the virus-producing virions. I suggest here to define life (an historical process) as the mode of existence of ribosome encoding organisms (cells) and capsid encoding organisms (viruses) and their ancestors. I propose to define an organism as an ensemble of integrated organs (molecular or cellular) producing individuals evolving through natural selection. The origin of life on our planet would correspond to the establishment of the first organism corresponding to this definition.

  10. Ebola Virus-Related Encephalitis.

    PubMed

    de Greslan, Thierry; Billhot, Magali; Rousseau, Claire; Mac Nab, Christine; Karkowski, Ludovic; Cournac, Jean-Marie; Bordes, Julien; Gagnon, Nicolas; Dubrous, Philippe; Duron, Sandrine; Moroge, Sophie; Quentin, Benoit; Koulibaly, Fassou; Bompaire, Flavie; Renard, Jean-Luc; Cellarier, Gilles

    2016-10-15

    Ebola patients frequently exhibit behavioral modifications with ideation slowing and aggressiveness, sometimes contrasting with mild severity of Ebola disease. We performed lumbar punctures in 3 patients with this presentation and found Ebola virus in all cerebrospinal fluid samples. This discovery helps to discuss the concept of a specific Ebola virus encephalitis. PMID:27418576

  11. Swine Influenza Virus: Emerging Understandings

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Introduction: In March-April 2009, a novel pandemic H1N1 emerged in the human population in North America [1]. The gene constellation of the emerging virus was demonstrated to be a combination of genes from swine influenza A viruses (SIV) of North American and Eurasian lineages that had never before...

  12. Paper Models Illustrating Virus Symmetry.

    ERIC Educational Resources Information Center

    McCarthy, D. A.

    1990-01-01

    Instructions are given for constructing two models, one to illustrate the general principles of symmetry in T=1, T=3, and T=4 viruses, and the other to illustrate the disposition of protein subunits in the T=3 plant viruses and the picornaviruses. (Author/CW)

  13. Oncolytic virus therapy for cancer.

    PubMed

    Goldufsky, Joe; Sivendran, Shanthi; Harcharik, Sara; Pan, Michael; Bernardo, Sebastian; Stern, Richard H; Friedlander, Philip; Ruby, Carl E; Saenger, Yvonne; Kaufman, Howard L

    2013-01-01

    The use of oncolytic viruses to treat cancer is based on the selection of tropic tumor viruses or the generation of replication selective vectors that can either directly kill infected tumor cells or increase their susceptibility to cell death and apoptosis through additional exposure to radiation or chemotherapy. In addition, viral vectors can be modified to promote more potent tumor cell death, improve the toxicity profile, and/or generate host antitumor immunity. A variety of viruses have been developed as oncolytic therapeutics, including adenovirus, vaccinia virus, herpesvirus, coxsackie A virus, Newcastle disease virus, and reovirus. The clinical development of oncolytic viral therapy has accelerated in the last few years, with several vectors entering clinical trials for a variety of cancers. In this review, current strategies to optimize the therapeutic effectiveness and safety of the major oncolytic viruses are discussed, and a summary of current clinical trials is provided. Further investigation is needed to characterize better the clinical impact of oncolytic viruses, but there are increasing data demonstrating the potential promise of this approach for the treatment of human and animal cancers.

  14. Oncolytic virus therapy for cancer

    PubMed Central

    Goldufsky, Joe; Sivendran, Shanthi; Harcharik, Sara; Pan, Michael; Bernardo, Sebastian; Stern, Richard H; Friedlander, Philip; Ruby, Carl E; Saenger, Yvonne; Kaufman, Howard L

    2013-01-01

    The use of oncolytic viruses to treat cancer is based on the selection of tropic tumor viruses or the generation of replication selective vectors that can either directly kill infected tumor cells or increase their susceptibility to cell death and apoptosis through additional exposure to radiation or chemotherapy. In addition, viral vectors can be modified to promote more potent tumor cell death, improve the toxicity profile, and/or generate host antitumor immunity. A variety of viruses have been developed as oncolytic therapeutics, including adenovirus, vaccinia virus, herpesvirus, coxsackie A virus, Newcastle disease virus, and reovirus. The clinical development of oncolytic viral therapy has accelerated in the last few years, with several vectors entering clinical trials for a variety of cancers. In this review, current strategies to optimize the therapeutic effectiveness and safety of the major oncolytic viruses are discussed, and a summary of current clinical trials is provided. Further investigation is needed to characterize better the clinical impact of oncolytic viruses, but there are increasing data demonstrating the potential promise of this approach for the treatment of human and animal cancers. PMID:27512656

  15. Group 2 vaccinia virus, Brazil.

    PubMed

    Assis, Felipe Lopes; Borges, Iara Apolinario; Ferreira, Paulo César Peregrino; Bonjardim, Cláudio Antônio; Trindade, Giliane de Souza; Lobato, Zélia Inês Portela; Guedes, Maria Isabel Maldonado; Mesquita, Vaz; Kroon, Erna Geessien; Abrahão, Jônatas Santos

    2012-12-01

    In 2011, vaccinia virus caused an outbreak of bovine vaccinia, affecting dairy cattle and dairy workers in Brazil. Genetic and phenotypic analyses identified this isolate as distinct from others recently identified, thereby reinforcing the hypothesis that different vaccinia virus strains co-circulate in Brazil.

  16. West Nile virus vaccine.

    PubMed

    Monath, T P; Arroyo, J; Miller, C; Guirakhoo, F

    2001-05-01

    Within the past 5 years, West Nile encephalitis has emerged as an important disease of humans and horses in Europe. In 1999, the disease appeared for the first time in the northeastern United States. West Nile virus (a mosquito-borne flavivirus) has flourished in the North American ecosystem and is expected to expand its geographic range. In this review, the rationale for a human and veterinary vaccine is presented and a novel approach for rapid development of a molecularly-defined, live, attenuated vaccine is described. The technology (ChimeriVax) is applicable to the development of vaccines against all flaviviruses, and products against Japanese encephalitis (a close relative of West Nile) and dengue are in or are nearing clinical trials, respectively. ChimeriVax vaccines utilize the safe and effective vaccine against the prototype flavivirus -yellow fever 17D- as a live vector. Infectious clone technology is used to replace the genes encoding the pre-membrane (prM) and envelope (E) protein of yellow fever 17D vaccine with the corresponding genes of the target virus (e.g., West Nile). The resulting chimeric virus contains the antigens responsible for protection against West Nile but retains the replication efficiency of yellow fever 17D. The ChimeriVax technology is well-suited to the rapid development of a West Nile vaccine, and clinical trials could begin as early as mid-2002. Other approaches to vaccine development are briefly reviewed. The aim of this brief review is to describe the features of West Nile encephalitis, a newly introduced infectious disease affecting humans, horses and wildlife in the United States; the rationale for rapid development of vaccines; and approaches to the development of vaccines against the disease.

  17. Role of CD4 epitopes outside the gp120-binding site during entry of human immunodeficiency virus type 1.

    PubMed Central

    Simon, J H; Stumbles, P; Signoret, N; Somoza, C; Puklavec, M; Sattentau, Q J; Barclay, A N; James, W

    1997-01-01

    CD4 is the primary receptor for human immunodeficiency virus (HIV). The binding site for the surface glycoprotein of HIV type 1 (HIV-1), gp120, has been mapped to the C'-C" region of domain 1 of CD4. Previously, we have shown that a mutant of rat CD4, in which this region was exchanged for that of human CD4, is able to mediate infection of human cells by HIV-1, suggesting that essential interactions between HIV and CD4 are confined to this region. Our observations appeared to conflict with mutagenesis and antibody studies which implicate regions of CD4 outside the gp120-binding site in postbinding events during viral entry. In order to resolve this issue, we have utilized a panel of anti-rat CD4 monoclonal antibodies in conjunction with the rat-human chimeric CD4 to distinguish sequence-specific from steric effects. We find that several antibodies to rat CD4 inhibit HIV infection in cells expressing the chimeric CD4 and that this is probably due to steric hinderance. In addition, we demonstrate that replacement of the rat CDR3-like region with its human homolog does not increase the affinity of the rat-human chimeric CD4 for gp120 or affect the exposure of gp41 following binding to CD4, providing further evidence that this region does not play a crucial role during entry of virus. PMID:8995673

  18. New aspects of influenza viruses.

    PubMed Central

    Shaw, M W; Arden, N H; Maassab, H F

    1992-01-01

    Influenza virus infections continue to cause substantial morbidity and mortality with a worldwide social and economic impact. The past five years have seen dramatic advances in our understanding of viral replication, evolution, and antigenic variation. Genetic analyses have clarified relationships between human and animal influenza virus strains, demonstrating the potential for the appearance of new pandemic reassortants as hemagglutinin and neuraminidase genes are exchanged in an intermediate host. Clinical trials of candidate live attenuated influenza virus vaccines have shown the cold-adapted reassortants to be a promising alternative to the currently available inactivated virus preparations. Modern molecular techniques have allowed serious consideration of new approaches to the development of antiviral agents and vaccines as the functions of the viral genes and proteins are further elucidated. The development of techniques whereby the genes of influenza viruses can be specifically altered to investigate those functions will undoubtedly accelerate the pace at which our knowledge expands. PMID:1310439

  19. Nonlytic spread of naked viruses.

    PubMed

    Bird, Sara W; Kirkegaard, Karla

    2015-01-01

    How do viruses spread from cell to cell? Enveloped viruses acquire their surrounding membranes by budding: either through the plasma membrane or an internal membrane of infected cells. Thus, a newly budded enveloped virus finds itself either in the extracellular milieu or in a lumenal compartment from which it can exit the cell by conventional secretion. On the other hand, naked viruses such as poliovirus, nodavirus, adenovirus, and SV40 lack an external membrane. They are simply protein-nucleic acid complexes within the cytoplasm or nucleus of the infected cell, and thus would seem to have no other exit route than cell lysis. We have presented the first documentation of nonlytic spread of a naked virus, and showed the interconnections between this event and the process or components of the autophagy pathway. PMID:25680079

  20. Nonlytic spread of naked viruses

    PubMed Central

    Bird, Sara W; Kirkegaard, Karla

    2015-01-01

    How do viruses spread from cell to cell? Enveloped viruses acquire their surrounding membranes by budding: either through the plasma membrane or an internal membrane of infected cells. Thus, a newly budded enveloped virus finds itself either in the extracellular milieu or in a lumenal compartment from which it can exit the cell by conventional secretion. On the other hand, naked viruses such as poliovirus, nodavirus, adenovirus, and SV40 lack an external membrane. They are simply protein-nucleic acid complexes within the cytoplasm or nucleus of the infected cell, and thus would seem to have no other exit route than cell lysis. We have presented the first documentation of nonlytic spread of a naked virus, and showed the interconnections between this event and the process or components of the autophagy pathway. PMID:25680079

  1. Movement of Viruses between Biomes

    PubMed Central

    Sano, Emiko; Carlson, Suzanne; Wegley, Linda; Rohwer, Forest

    2004-01-01

    Viruses are abundant in all known ecosystems. In the present study, we tested the possibility that viruses from one biome can successfully propagate in another. Viral concentrates were prepared from different near-shore marine sites, lake water, marine sediments, and soil. The concentrates were added to microcosms containing dissolved organic matter as a food source (after filtration to allow 100-kDa particles to pass through) and a 3% (vol/vol) microbial inoculum from a marine water sample (after filtration through a 0.45-μm-pore-size filter). Virus-like particle abundances were then monitored using direct counting. Viral populations from lake water, marine sediments, and soil were able to replicate when they were incubated with the marine microbes, showing that viruses can move between different ecosystems and propagate. These results imply that viruses can laterally transfer DNA between microbes in different biomes. PMID:15466522

  2. The ecology of Ebola virus.

    PubMed

    Groseth, Allison; Feldmann, Heinz; Strong, James E

    2007-09-01

    Since Ebola virus was first identified more than 30 years ago, tremendous progress has been made in understanding the molecular biology and pathogenesis of this virus. However, the means by which Ebola virus is maintained and transmitted in nature remains unclear despite dedicated efforts to answer these questions. Recent work has provided new evidence that fruit bats might have a role as a reservoir species, but it is not clear whether other species are also involved or how transmission to humans or apes takes place. Two opposing hypotheses for Ebola emergence have surfaced; one of long-term local persistence in a cryptic and infrequently contacted reservoir, versus another of a more recent introduction of the virus and directional spread through susceptible populations. Nevertheless, with the increasing frequency of human filovirus outbreaks and the tremendous impact of infection on the already threatened great ape populations, there is an urgent need to better understand the ecology of Ebola virus in nature. PMID:17698361

  3. Biosensing with Virus Electrode Hybrids

    PubMed Central

    Mohan, Kritika; Penner, Reginald M.; Weiss, Gregory A.

    2015-01-01

    Virus electrodes address two major challenges associated with biosensing. First, the surface of the viruses can be readily tailored for specific, high affinity binding to targeted biomarkers. Second, the viruses are entrapped in a conducting polymer for electrical resistance-based, quantitative measurement of biomarker concentration. To further enhance device sensitivity, two different ligands can be attached to the virus surface, and increase the apparent affinity for the biomarker. In the example presented here, the two ligands bind to the analyte in a bidentate binding mode with chelate-based avidity effect, and result in an 100 pM experimentally observed limit of detection for the cancer biomarker prostate-specific membrane antigen. The approach does not require enzymatic amplification, and allows reagent-free, real-time measurements. This article presents general protocols for the development of such biosensors with modified viruses for the enhanced detection of arbitrary target proteins. PMID:26344233

  4. [Classification of viruses by computer].

    PubMed

    Ageeva, O N; Andzhaparidze, O G; Kibardin, V M; Nazarova, G M; Pleteneva, E A

    1982-01-01

    The study used the information mass containing information on 83 viruses characterized by 41 markers. The suitability of one of the variants of cluster analysis for virus classification was demonstrated. It was established that certain stages of automatic allotment of viruses into groups by the degree of similarity of their properties end the formation of groups which consist of viruses sufficiently close to each other by their properties and are sufficiently isolated. Comparison of these groups with the classification proposed by the ICVT established their correspondence to individual families. Analysis of the obtained classification system permits sufficiently grounded conclusions to be drawn with regard to the classification position of certain viruses, the classification of which has not yet been completed by the ICVT.

  5. Marine Viruses: Truth or Dare

    NASA Astrophysics Data System (ADS)

    Breitbart, Mya

    2012-01-01

    Over the past two decades, marine virology has progressed from a curiosity to an intensely studied topic of critical importance to oceanography. At concentrations of approximately 10 million viruses per milliliter of surface seawater, viruses are the most abundant biological entities in the oceans. The majority of these viruses are phages (viruses that infect bacteria). Through lysing their bacterial hosts, marine phages control bacterial abundance, affect community composition, and impact global biogeochemical cycles. In addition, phages influence their hosts through selection for resistance, horizontal gene transfer, and manipulation of bacterial metabolism. Recent work has also demonstrated that marine phages are extremely diverse and can carry a variety of auxiliary metabolic genes encoding critical ecological functions. This review is structured as a scientific "truth or dare," revealing several well-established "truths" about marine viruses and presenting a few "dares" for the research community to undertake in future studies.

  6. Virus assembly, allostery, and antivirals

    PubMed Central

    Zlotnick, Adam; Mukhopadhyay, Suchetana

    2010-01-01

    Assembly of virus capsids and surface proteins must be regulated to ensure that the resulting complex is an infectious virion. Here we examine assembly of virus capsids, focusing on hepatitis B virus and bacteriophage MS2, and formation of glycoproteins in the alphaviruses. These systems are structurally and biochemically well-characterized and are simplest-case paradigms of self-assembly. Published data suggest that capsid and glycoprotein assembly is subject to allosteric regulation, that is, regulation at the level of conformational change. The hypothesis that allostery is a common theme in viruses suggests that deregulation of capsid and glycoprotein assembly by small molecule effectors will be an attractive antiviral strategy, as has been demonstrated with hepatitis B virus. PMID:21163649

  7. Endotoxin-induced mortality in rats is reduced by nitrones

    SciTech Connect

    Hamburger, S.A.; McCay, P.B. )

    1989-12-01

    The goal of these investigations was to determine if nitrone spin-trapping agents can alter mortality associated with endotoxemia in the rat. Reactive free radicals attack nitrone spin-trapping agents forming relatively reactive, persistent free radical spin adducts. We administered 85 mM (10 ml/kg) of alpha-phenyl N-tert-butyl nitrone (PBN), alpha-4-pyridyl-N-oxide N-tert-butyl nitrone (4-POBN), 5,5-dimethyl-1-pyrroline-N-oxide (DMPO), or vehicle (saline i.p.) 30 min before endotoxin (25 mg/kg i.p.) or vehicle to Sprague-Dawley (SD) or Holtzman virus-free (HVF) rats (n = 10-17/group). All vehicle-treated rats receiving endotoxin were dead by 1 day. At 7 days, 83% of PBN-treated SD, 42% of PBN- or POBN-treated HVF, and 25% of DMPO-treated HVF rats were alive. The difference in survival of PBN-treated animals between strains may reflect the higher susceptibility of HVF rats to endotoxin. The observed reduction in mortality may be related to the well-established capacity of spin-trapping agents to capture reactive free radicals that may be generated in target tissues in response to endotoxin, and that would otherwise react with cell components and produce tissue injury.

  8. Structure, origin, and transforming activity of feline leukemia virus-myc recombinant provirus FTT.

    PubMed Central

    Doggett, D L; Drake, A L; Hirsch, V; Rowe, M E; Stallard, V; Mullins, J I

    1989-01-01

    A myc-containing recombinant feline leukemia provirus, designated FTT, was molecularly cloned from the cat T-cell lymphoma line F422. Its transforming activity, as well as the nucleotide sequence of the 3' 2.7 kilobases of FTT, including v-myc, was determined. The predicted v-myc protein differs from feline c-myc by three amino acid changes and is truncated by two amino acids at the carboxyl terminus. Comparison with feline leukemia virus (FeLV), feline c-myc, and other FeLV proviruses indicates that recombination junctions involved in the generation of FeLV-onc viruses occur at preferred locations within the virus. They usually follow or occur within the sequence ACCCC at 5' junctions and may result from homologous recombination between sequences of marked purine-pyrimidine strand bias, especially at 3' junctions. Some recombination sites also resemble recombinase recognition sequences utilized in immunoglobulin and T-cell receptor variable-region joining. Transfection of primary rat embryo fibroblasts and subsequent in vivo analysis revealed that morphologic and tumorigenic transformation require cotransfection of FTT with human EJ-ras DNA; neither gene alone is sufficient. FTT v-myc is expressed in these transformed rat cells as a 3.0-kilobase subgenomic RNA; however, in contrast to the depressed level of c-myc expression in v-myc-involved feline tumors, steady-state levels of rat c-myc RNA and protein are apparently unaltered. Images PMID:2539507

  9. The Acute bee paralysis virus-Kashmir bee virus-Israeli acute paralysis virus complex.

    PubMed

    de Miranda, Joachim R; Cordoni, Guido; Budge, Giles

    2010-01-01

    Acute bee paralysis virus (ABPV), Kashmir bee virus (KBV) and Israeli acute paralysis virus (IAPV) are part of a complex of closely related viruses from the Family Dicistroviridae. These viruses have a widespread prevalence in honey bee (Apis mellifera) colonies and a predominantly sub-clinical etiology that contrasts sharply with the extremely virulent pathology encountered at elevated titres, either artificially induced or encountered naturally. These viruses are frequently implicated in honey bee colony losses, especially when the colonies are infested with the parasitic mite Varroa destructor. Here we review the historical and recent literature of this virus complex, covering history and origins; the geographic, host and tissue distribution; pathology and transmission; genetics and variation; diagnostics, and discuss these within the context of the molecular and biological similarities and differences between the viruses. We also briefly discuss three recent developments relating specifically to IAPV, concerning its association with Colony Collapse Disorder, treatment of IAPV infection with siRNA and possible honey bee resistance to IAPV.

  10. Hepatitis E Virus Infection

    PubMed Central

    Dalton, Harry R.; Abravanel, Florence; Izopet, Jacques

    2014-01-01

    SUMMARY Hepatitis E virus (HEV) infection is a worldwide disease. An improved understanding of the natural history of HEV infection has been achieved within the last decade. Several reservoirs and transmission modes have been identified. Hepatitis E is an underdiagnosed disease, in part due to the use of serological assays with low sensitivity. However, diagnostic tools, including nucleic acid-based tests, have been improved. The epidemiology and clinical features of hepatitis E differ between developing and developed countries. HEV infection is usually an acute self-limiting disease, but in developed countries it causes chronic infection with rapidly progressive cirrhosis in organ transplant recipients, patients with hematological malignancy requiring chemotherapy, and individuals with HIV. HEV also causes extrahepatic manifestations, including a number of neurological syndromes and renal injury. Acute infection usually requires no treatment, but chronic infection should be treated by reducing immunosuppression in transplant patients and/or the use of antiviral therapy. In this comprehensive review, we summarize the current knowledge about the virus itself, as well as the epidemiology, diagnostics, natural history, and management of HEV infection in developing and developed countries. PMID:24396139

  11. Chikungunya virus infection.

    PubMed

    Sam, I-C; AbuBakar, S

    2006-06-01

    Chikungunya virus (CHIKV) is a mosquito-borne alphavirus which causes epidemic fever, rash and polyarthralgia in Africa and Asia. Two outbreaks have been reported in Malaysia, in Klang, Selangor (1998) and Bagan Panchor, Perak (2006). It is not known if the outbreaks were caused by the recent introduction of CHIKV, or if the virus was already circulating in Malaysia. Seroprevalence studies from the 1960s suggested previous disease activity in certain parts of the country. In Asia, CHIKV is thought to be transmitted by the same mosquitoes as dengue, Aedes aegypti and Ae. albopictus. Due to similarities in clinical presentation with dengue, limited awareness, and a lack of laboratory diagnostic capability, CHIKV is probably often underdiagnosed or misdiagnosed as dengue. Treatment is supportive. The prognosis is generally good, although some patients experience chronic arthritis. With no vaccine or antiviral available, prevention and control depends on surveillance, early identification of outbreaks, and vector control. CHIKV should be borne in mind in sporadic cases, and in patients epidemiologically linked to ongoing local or international outbreaks or endemic areas.

  12. Dengue virus vaccine development.

    PubMed

    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.

  13. Hepatitis E virus infection.

    PubMed

    Kamar, Nassim; Dalton, Harry R; Abravanel, Florence; Izopet, Jacques

    2014-01-01

    Hepatitis E virus (HEV) infection is a worldwide disease. An improved understanding of the natural history of HEV infection has been achieved within the last decade. Several reservoirs and transmission modes have been identified. Hepatitis E is an underdiagnosed disease, in part due to the use of serological assays with low sensitivity. However, diagnostic tools, including nucleic acid-based tests, have been improved. The epidemiology and clinical features of hepatitis E differ between developing and developed countries. HEV infection is usually an acute self-limiting disease, but in developed countries it causes chronic infection with rapidly progressive cirrhosis in organ transplant recipients, patients with hematological malignancy requiring chemotherapy, and individuals with HIV. HEV also causes extrahepatic manifestations, including a number of neurological syndromes and renal injury. Acute infection usually requires no treatment, but chronic infection should be treated by reducing immunosuppression in transplant patients and/or the use of antiviral therapy. In this comprehensive review, we summarize the current knowledge about the virus itself, as well as the epidemiology, diagnostics, natural history, and management of HEV infection in developing and developed countries. PMID:24396139

  14. Inhibition of human immunodeficiency virus type 1 replication by SDZ NIM 811, a nonimmunosuppressive cyclosporine analog.

    PubMed Central

    Rosenwirth, B; Billich, A; Datema, R; Donatsch, P; Hammerschmid, F; Harrison, R; Hiestand, P; Jaksche, H; Mayer, P; Peichl, P

    1994-01-01

    (Me-Ile-4)cyclosporin (SDZ NIM 811) is a 4-substituted cyclosporin which is devoid of immunosuppressive activity but retains full capacity for binding to cyclophilin and exhibits potent anti-human immunodeficiency virus type 1 (HIV-1) activity. SDZ NIM 811 selectively inhibits HIV-1 replication in T4 lymphocyte cell lines, in a monocytic cell line, and in HeLa T4 cells. Furthermore, its antiviral activity against laboratory strains and against clinical isolates from geographically distinct regions in primary T4 lymphocytes and in primary monocytes (50% inhibitory concentration = 0.011 to 0.057 micrograms/ml) was demonstrated. SDZ NIM 811 does not inhibit proviral gene expression or virus-specific enzyme functions, either free or bound to cyclophilin. The compound does not influence CD4 expression or inhibit fusion between virus-infected and uninfected cells. SDZ NIM 811 was, however, found to block formation of infectious particles from chronically infected cells. Oral administration to mice, rats, dogs, and monkeys resulted in levels in blood considerably exceeding the drug concentration, which completely blocked virus replication in primary cells. SDZ NIM 811 caused changes of toxicity parameters in rats to a smaller degree than cyclosporine (formerly cyclosporin A). Thus, the potent and selective anti-HIV-1 activity of SDZ NIM 811 and its favorable pharmacokinetic behavior together with its lower nephrotoxicity than that of cyclosporine make this compound a promising candidate for development as an anti-HIV drug. PMID:7527198

  15. Comparison of Immunohistochemistry and Virus Isolation for Diagnosis of West Nile Virus

    PubMed Central

    Ellis, Angela E.; Mead, Daniel G.; Allison, Andrew B.; Gibbs, Samantha E. J.; Gottdenker, Nicole L.; Stallknecht, David E.; Howerth, Elizabeth W.

    2005-01-01

    Immunohistochemistry and virus isolation were performed on 1,057 birds. Immunohistochemistry, virus isolation, or both found 325 birds to be West Nile virus positive. Of these, 271 were positive by both methods. These results indicate that virus isolation and immunohistochemistry are approximately equal in their ability to detect West Nile virus. PMID:15956415

  16. Genome Sequence of Bivens Arm Virus, a Tibrovirus Belonging to the Species Tibrogargan virus (Mononegavirales: Rhabdoviridae)

    PubMed Central

    Hensley, Lisa E.

    2015-01-01

    The new rhabdoviral genus Tibrovirus currently has two members, Coastal Plains virus and Tibrogargan virus. Here, we report the coding-complete genome sequence of a putative member of this genus, Bivens Arm virus. A genomic comparison reveals Bivens Arm virus to be closely related to, but distinct from, Tibrogargan virus. PMID:25792044

  17. A single vertebrate DNA virus protein disarms invertebrate immunity to RNA virus infection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Virus-host interactions drive a remarkable diversity of immune responses and countermeasures. While investigating virus-invertebrate host interactions we found that two RNA viruses with broad host ranges, vesicular stomatitis virus (VSV) and Sindbis virus (SINV), were unable to infect certain Lepido...

  18. Infectious vaccinia virus recombinants that express hepatitis B virus surface antigen

    NASA Astrophysics Data System (ADS)

    Smith, Geoffrey L.; Mackett, Michael; Moss, Bernard

    1983-04-01

    Potential live vaccines against hepatitis B virus have been produced. The coding sequence for hepatitis B virus surface antigen (HBsAg) has been inserted into the vaccinia virus genome under control of vaccinia virus early promoters. Cells infected with these vaccinia virus recombinants synthesize and excrete HBsAg and vaccinated rabbits rapidly produce antibodies to HBsAg.

  19. Influenza: a virus of our times

    PubMed Central

    McCaughey, Conall

    2010-01-01

    Viruses are successful and omnipresent. Influenza A is a particularly important virus of humans. The article reviews the 2009 emergence of the pandemic influenza A virus, focusing on the potential origin of the virus and the distinctive clinical and epidemiological impact of the 2009 pandemic. PMID:21116418

  20. Safe Computing: An Overview of Viruses.

    ERIC Educational Resources Information Center

    Wodarz, Nan

    2001-01-01

    A computer virus is a program that replicates itself, in conjunction with an additional program that can harm a computer system. Common viruses include boot-sector, macro, companion, overwriting, and multipartite. Viruses can be fast, slow, stealthy, and polymorphic. Anti-virus products are described. (MLH)

  1. Antiviral responses of human Leydig cells to mumps virus infection or poly I:C stimulation

    PubMed Central

    Le Tortorec, A.; Denis, H.; Satie, A-P.; Patard, J-J.; Ruffault, A.; Jégou, B.; Dejucq-Rainsford, N.

    2008-01-01

    BACKGROUND The immuno-privileged status of the testis is essential to the maintenance of its functions, and innate immunity is likely to play a key role in limiting harmful viral infections, as demonstrated in the rat. In men mumps virus infects Leydig cells and has deleterious effects on testosterone production and spermatogenesis. The aim of this study was to test whether mumps virus infection of isolated human Leydig cells was associated with an inhibition of their innate antiviral defences. METHODS Leydig cell production of mRNA and protein for interferons (IFNs) and of three antiviral proteins—2′5′ oligoadenylate synthetase (2′5′OAS), double-stranded RNA-activated protein kinase (PKR) and MxA—was investigated, in the absence or presence of mumps virus or viral stimuli including poly I:C, a mimetic of RNA viruses replication product. RESULTS Stimulated or not, human Leydig cells appeared unable to produce routinely detectable IFNs α, β and γ. Although the level of PKR remained unchanged after stimulation, the expression of 2′5′OAS and MxA was enhanced following either mumps virus or poly I:C exposure (P < 0.05 versus control). CONCLUSIONS Overall, our results demonstrate that mumps virus replication in human Leydig cells is not associated with a specific inhibition of IFNs or 2′5′OAS, MxA and PKR production and that these cells display relatively weak endogenous antiviral abilities, as opposed to their rat counterparts. PMID:18567898

  2. The IFITMs Inhibit Zika Virus Replication.

    PubMed

    Savidis, George; Perreira, Jill M; Portmann, Jocelyn M; Meraner, Paul; Guo, Zhiru; Green, Sharone; Brass, Abraham L

    2016-06-14

    Zika virus has emerged as a severe health threat with a rapidly expanding range. The IFITM family of restriction factors inhibits the replication of a broad range of viruses, including the closely related flaviruses West Nile virus and dengue virus. Here, we show that IFITM1 and IFITM3 inhibit Zika virus infection early in the viral life cycle. Moreover, IFITM3 can prevent Zika-virus-induced cell death. These results suggest that strategies to boost the actions and/or levels of the IFITMs might be useful for inhibiting a broad range of emerging viruses.

  3. Animal models on HTLV-1 and related viruses: what did we learn?

    PubMed Central

    Hajj, Hiba El; Nasr, Rihab; Kfoury, Youmna; Dassouki, Zeina; Nasser, Roudaina; Kchour, Ghada; Hermine, Olivier; de Thé, Hugues; Bazarbachi, Ali

    2012-01-01

    Retroviruses are associated with a wide variety of diseases, including immunological, neurological disorders, and different forms of cancer. Among retroviruses, Oncovirinae regroup according to their genetic structure and sequence, several related viruses such as human T-cell lymphotropic viruses types 1 and 2 (HTLV-1 and HTLV-2), simian T cell lymphotropic viruses types 1 and 2 (STLV-1 and STLV-2), and bovine leukemia virus (BLV). As in many diseases, animal models provide a useful tool for the studies of pathogenesis, treatment, and prevention. In the current review, an overview on different animal models used in the study of these viruses will be provided. A specific attention will be given to the HTLV-1 virus which is the causative agent of adult T-cell leukemia/lymphoma (ATL) but also of a number of inflammatory diseases regrouping the HTLV-associated myelopathy/tropical spastic paraparesis (HAM/TSP), infective dermatitis and some lung inflammatory diseases. Among these models, rabbits, monkeys but also rats provide an excellent in vivo tool for early HTLV-1 viral infection and transmission as well as the induced host immune response against the virus. But ideally, mice remain the most efficient method of studying human afflictions. Genetically altered mice including both transgenic and knockout mice, offer important models to test the role of specific viral and host genes in the development of HTLV-1-associated leukemia. The development of different strains of immunodeficient mice strains (SCID, NOD, and NOG SCID mice) provide a useful and rapid tool of humanized and xenografted mice models, to test new drugs and targeted therapy against HTLV-1-associated leukemia, to identify leukemia stem cells candidates but also to study the innate immunity mediated by the virus. All together, these animal models have revolutionized the biology of retroviruses, their manipulation of host genes and more importantly the potential ways to either prevent their infection or to

  4. Chemical inactivation of recombinant vaccinia viruses and the effects on antigenicity and immunogenicity of recombinant simian immunodeficiency virus envelope glycoproteins.

    PubMed

    Hulskotte, E G; Dings, M E; Norley, S G; Osterhaus, A D

    1997-12-01

    The efficiency of paraformaldehyde (PFA) and binary ethylenimine (BEI) in inactivating recombinant vaccinia virus (rVV), present in baby hamster kidney cells expressing simian immunodeficiency virus envelope glycoproteins (SIV-Env), was measured in a series of inactivation studies. Both compounds were shown to be effective in reducing rVV titres. The use of standard 3-day titration assays proved to be inadequate to measure PFA inactivation, since upon prolonged incubation, residual rVV infectivity was detected in cultures negative at 3 days. Different procedures using PFA or BEI were selected to assess their influence on the antigenicity and immunogenicity or rVV expressed SIV-Env. Antigenicity, as defined by the ability to react with a panel of monoclonal antibodies recognizing major antigenic sites, and immunogenicity, as defined by the ability to induce SIV envelope specific and virus neutralizing serum antibodies in rats, proved to be preserved after either inactivation procedure. These data show that both protocols using PFA or BEI can be used successfully as part of the procedures to remove residual rVV infectivity.

  5. Defining Life: The Virus Viewpoint

    NASA Astrophysics Data System (ADS)

    Forterre, Patrick

    2010-04-01

    Are viruses alive? Until very recently, answering this question was often negative and viruses were not considered in discussions on the origin and definition of life. This situation is rapidly changing, following several discoveries that have modified our vision of viruses. It has been recognized that viruses have played (and still play) a major innovative role in the evolution of cellular organisms. New definitions of viruses have been proposed and their position in the universal tree of life is actively discussed. Viruses are no more confused with their virions, but can be viewed as complex living entities that transform the infected cell into a novel organism—the virus—producing virions. I suggest here to define life (an historical process) as the mode of existence of ribosome encoding organisms (cells) and capsid encoding organisms (viruses) and their ancestors. I propose to define an organism as an ensemble of integrated organs (molecular or cellular) producing individuals evolving through natural selection. The origin of life on our planet would correspond to the establishment of the first organism corresponding to this definition.

  6. Viruses and interactomes in translation.

    PubMed

    Meyniel-Schicklin, Laurène; de Chassey, Benoît; André, Patrice; Lotteau, Vincent

    2012-07-01

    A decade of high-throughput screenings for intraviral and virus-host protein-protein interactions led to the accumulation of data and to the development of theories on laws governing interactome organization for many viruses. We present here a computational analysis of intraviral protein networks (EBV, FLUAV, HCV, HSV-1, KSHV, SARS-CoV, VACV, and VZV) and virus-host protein networks (DENV, EBV, FLUAV, HCV, and VACV) from up-to-date interaction data, using various mathematical approaches. If intraviral networks seem to behave similarly, they are clearly different from the human interactome. Viral proteins target highly central human proteins, which are precisely the Achilles' heel of the human interactome. The intrinsic structural disorder is a distinctive feature of viral hubs in virus-host interactomes. Overlaps between virus-host data sets identify a core of human proteins involved in the cellular response to viral infection and in the viral capacity to hijack the cell machinery for viral replication. Host proteins that are strongly targeted by a virus seem to be particularly attractive for other viruses. Such protein-protein interaction networks and their analysis represent a powerful resource from a therapeutic perspective.

  7. Virus infection and knee injury.

    PubMed Central

    Driscoll, P; Venner, R; Clements, G B

    1987-01-01

    Serological evidence of virus infection was sought in 31 consecutive patients presenting with knee swelling and compared with age/sex-matched controls. In a normal age/sex-matched control group, 42% of patients had evidence of recent or past infection with Coxsackie B virus, emphasising the care required in the evaluation of the significance of Coxsackie B neutralization titres in individual patients. Of 12 patients presenting with knee swelling and a history of a twisting injury, eight had serological evidence of recent or past infection with Coxsackie B virus, and one had evidence of a current adenovirus infection. PMID:2825728

  8. Marburg Virus Reverse Genetics Systems

    PubMed Central

    Schmidt, Kristina Maria; Mühlberger, Elke

    2016-01-01

    The highly pathogenic Marburg virus (MARV) is a member of the Filoviridae family and belongs to the group of nonsegmented negative-strand RNA viruses. Reverse genetics systems established for MARV have been used to study various aspects of the viral replication cycle, analyze host responses, image viral infection, and screen for antivirals. This article provides an overview of the currently established MARV reverse genetic systems based on minigenomes, infectious virus-like particles and full-length clones, and the research that has been conducted using these systems. PMID:27338448

  9. Xenotropic Murine Leukemia Virus-related Virus (XMRV) Backgrounder

    Cancer.gov

    Researchers have not found evidence that XMRV causes any diseases in humans or in animals. The presence of an infectious agent, such as a virus, in diseased tissue does not mean that the agent causes the disease.

  10. Capillary electrophoresis of viruses, subviral particles and virus complexes.

    PubMed

    Kremser, Leopold; Bilek, Gerhard; Blaas, Dieter; Kenndler, Ernst

    2007-07-01

    CZE and CIEF were so far applied to the analysis of tobacco mosaic virus, Semliki forest virus, human rhinovirus, adenovirus, norovirus and the bacteriophages T5 and MS2. The concentration of viral or subviral particles, of capsid proteins and viral genomes were determined, their electrophoretic mobilities and pI values were measured and bioaffinity reactions between viruses and antibodies, antibody fragments and receptor fragments were assessed. The role of detergents added to the BGE to obtain reproducible electrophoretic conditions was elucidated. The analytes were detected via their UV-absorbance or via fluorescence after derivatization of the viral capsid, the nucleic acid, or both. A new dimension to the detection is added by the possibility of making use of the viral infectivity. At least in theory, this allows for the unequivocal identification of a single infectious virus particle after collection at the capillary outlet. This review summarizes the 25 papers so far published on this topic.

  11. Virus isolation for diagnosing dengue virus infections in returning travelers.

    PubMed

    Teichmann, D; Göbels, K; Niedrig, M; Sim-Brandenburg, J-W; Làge-Stehr, J; Grobusch, M P

    2003-11-01

    Dengue fever is recognized as one of the most frequent imported acute febrile illnesses affecting European tourists returning from the tropics. In order to assess the value of virus isolation for the diagnosis of dengue fever, 70 cases of dengue fever confirmed in German travelers during the period 1993-2001 were analyzed retrospectively. In 26 patients who had developed acute febrile illness within 2 weeks following their return from a trip to a dengue-endemic area, 9 of 13 attempts to isolate the virus were successful in sera drawn 1-5 days and 2 of 13 sera drawn 6-10 days after the onset of illness. DEN-1 was the most frequent serotype isolated. If performed early, virus isolation is a reliable tool for detecting dengue virus in returning travelers.

  12. Antiviral Drugs for Viruses Other Than Human Immunodeficiency Virus

    PubMed Central

    Razonable, Raymund R.

    2011-01-01

    Most viral diseases, with the exception of those caused by human immunodeficiency virus, are self-limited illnesses that do not require specific antiviral therapy. The currently available antiviral drugs target 3 main groups of viruses: herpes, hepatitis, and influenza viruses. With the exception of the antisense molecule fomivirsen, all antiherpes drugs inhibit viral replication by serving as competitive substrates for viral DNA polymerase. Drugs for the treatment of influenza inhibit the ion channel M2 protein or the enzyme neuraminidase. Combination therapy with Interferon-α and ribavirin remains the backbone treatment for chronic hepatitis C; the addition of serine protease inhibitors improves the treatment outcome of patients infected with hepatitis C virus genotype 1. Chronic hepatitis B can be treated with interferon or a combination of nucleos(t)ide analogues. Notably, almost all the nucleos(t) ide analogues for the treatment of chronic hepatitis B possess anti–human immunodeficiency virus properties, and they inhibit replication of hepatitis B virus by serving as competitive substrates for its DNA polymerase. Some antiviral drugs possess multiple potential clinical applications, such as ribavirin for the treatment of chronic hepatitis C and respiratory syncytial virus and cidofovir for the treatment of cytomegalovirus and other DNA viruses. Drug resistance is an emerging threat to the clinical utility of antiviral drugs. The major mechanisms for drug resistance are mutations in the viral DNA polymerase gene or in genes that encode for the viral kinases required for the activation of certain drugs such as acyclovir and ganciclovir. Widespread antiviral resistance has limited the clinical utility of M2 inhibitors for the prevention and treatment of influenza infections. This article provides an overview of clinically available antiviral drugs for the primary care physician, with a special focus on pharmacology, clinical uses, and adverse effects. PMID

  13. Cucumber mosaic virus, a model for RNA virus evolution.

    PubMed

    Roossinck, M J

    2001-03-01

    Summary Taxonomic relationships: Cucumber mosaic virus (CMV) is the type member of the Cucumovirus genus, in the family Bromoviridae. Additional members of the genus are Peanut stunt virus (PSV) and Tomato aspermy virus (TAV). The RNAs 3 of all members of the genus can be exchanged and still yield a viable virus, while the RNAs 1 and 2 can only be exchanged within a species. Physical properties: The virus particles are about 29 nm in diameter, and are composed of 180 subunits (T = 3 icosahedral symmetry). The particles sediment with an s value of approximately 98. The virions contain 18% RNA, and are highly labile, relying on RNA-protein interactions for their integrity. The three genomic RNAs, designated RNA 1 (3.3 kb in length), RNA 2 (3.0 kb) and RNA 3 (2.2 kb) are packaged in individual particles; a subgenomic RNA, RNA 4 (1.0 kb), is packaged with the genomic RNA 3, making all the particles roughly equivalent in composition. In some strains an additional subgenomic RNA, RNA 4A is also encapsidated at low levels. The genomic RNAs are single stranded, plus sense RNAs with 5' cap structures, and 3' conserved regions that can be folded into tRNA-like structures. Satellite RNAs: CMV can harbour molecular parasites known as satellite RNAs (satRNAs) that can dramatically alter the symptom phenotype induced by the virus. The CMV satRNAs do not encode any proteins but rely on the RNA for their biological activity. Hosts: CMV infects over 1000 species of hosts, including members of 85 plant families, making it the broadest host range virus known. The virus is transmitted from host to host by aphid vectors, in a nonpersistent manner. Useful web sites: http://mmtsb.scripps.edu/viper/1f15.html (structure); http://www.ncbi.nlm.nih.gov/ICTVdb/ICTVdB/10040001.htm (general information).

  14. Characterization of Sepik and Entebbe bat viruses closely related to yellow fever virus.

    PubMed

    Kuno, Goro; Chang, Gwong-Jen J

    2006-12-01

    Yellow fever virus has a special place in medical history as the first animal virus isolated and as the prototype virus in the genus Flavivirus, which contains many serious human pathogens. Only recently, its closely related viruses within the group were identified phylogenetically. In this study, we obtained complete or near complete genome sequences of two viruses most closely related to yellow fever virus: Sepik virus of Papua New Guinea and Entebbe bat virus of Africa. Based on full-genomic characterization and genomic traits among related viruses, we identified Sepik virus to be most closely related to yellow fever virus and analyzed the pattern of repeat and conserved sequence motifs in the 3'-noncoding region among the members of yellow fever virus cluster. We also discuss the geographic dispersal as a part of ecological traits of this lineage of flaviviruses.

  15. Zika virus infections.

    PubMed

    de Laval, F; Leparc-Goffart, I; Meynard, J-B; Daubigny, H; Simon, F; Briolant, S

    2016-05-01

    Since its discovery in 1947 in Uganda, the Zika virus (ZIKV) remained in the shadows emerging in 2007 in Micronesia, where hundreds of dengue-like syndromes were reported. Then, in 2013-2014, it was rife in French Polynesia, where the first neurological effects were observed. More recently, its arrival in Brazil was accompanied by an unusually high number of children with microcephaly born to mothers infected with ZIKV during the first trimester of pregnancy. In 2016, the World Health Organization declared ZIKV infection to be a public health emergency and now talks about a ZIKV pandemic. This review aims to summarize the current knowledge about ZIKV infection, successively addressing its transmission, epidemiology, clinical aspects, diagnosis, treatment, and prevention before discussing some perspectives. PMID:27412976

  16. West Nile virus meningoencephalitis

    PubMed Central

    DeBiasi, Roberta L.; Tyler, Kenneth L.

    2013-01-01

    SUMMARY Since its first appearance in the US in 1999, West Nile virus (WNV) has emerged as the most common cause of epidemic meningoencephalitis in North America. In the 6 years following the 1999 outbreak, the geographic range and burden of the disease in birds, mosquitoes and humans has greatly expanded to include the 48 contiguous US and 7 Canadian provinces, as well as Mexico, the Caribbean islands and Colombia. WNV has shown an increasing propensity for neuroinvasive disease over the past decade, with varied presentations including meningitis, encephalitis and acute flaccid paralysis. Although neuroinvasive disease occurs in less than 1% of infected individuals, it is associated with high mortality. From 1999–2005, more than 8,000 cases of neuroinvasive WNV disease were reported in the US, resulting in over 780 deaths. In this review, we discuss epidemiology, risk factors, clinical features, diagnosis and prognosis of WNV meningoencephalitis, along with potential treatments. PMID:16932563

  17. Junin virus structural proteins.

    PubMed Central

    De Martínez Segovia, Z M; De Mitri, M I

    1977-01-01

    Polyacrylamide gel electrophoresis of purified Junin virus revealed six distinct structural polypeptides, two major and four minor ones. Four of these polypeptides appeared to be covalently linked with carbohydrate. The molecular weights of the six proteins, estimated by coelectrophoresis with marker proteins, ranged from 25,000 to 91,000. One of the two major components (number 3) was identified as a nucleoprotein and had a molecular weight of 64,000. It was the most prominent protein and was nonglycosylated. The other major protein (number 5), with a molecular weight of 38,000, was a glucoprotein and a component of the viral envelope. The location on the virion of three additional glycopeptides with molecular weights of 91,000, 72,000, and 52,000, together with a protein with a molecular weight of 25,000, was not well defined. PMID:189088

  18. Zika virus infections.

    PubMed

    de Laval, F; Leparc-Goffart, I; Meynard, J-B; Daubigny, H; Simon, F; Briolant, S

    2016-05-01

    Since its discovery in 1947 in Uganda, the Zika virus (ZIKV) remained in the shadows emerging in 2007 in Micronesia, where hundreds of dengue-like syndromes were reported. Then, in 2013-2014, it was rife in French Polynesia, where the first neurological effects were observed. More recently, its arrival in Brazil was accompanied by an unusually high number of children with microcephaly born to mothers infected with ZIKV during the first trimester of pregnancy. In 2016, the World Health Organization declared ZIKV infection to be a public health emergency and now talks about a ZIKV pandemic. This review aims to summarize the current knowledge about ZIKV infection, successively addressing its transmission, epidemiology, clinical aspects, diagnosis, treatment, and prevention before discussing some perspectives.

  19. Varicella-zoster virus.

    PubMed Central

    Arvin, A M

    1996-01-01

    Varicella-zoster virus (VZV) is a ubiquitous human alphaherpesvirus that causes varicella (chicken pox) and herpes zoster (shingles). Varicella is a common childhood illness, characterized by fever, viremia, and scattered vesicular lesions of the skin. As is characteristic of the alphaherpesviruses, VZV establishes latency in cells of the dorsal root ganglia. Herpes zoster, caused by VZV reactivation, is a localized, painful, vesicular rash involving one or adjacent dermatomes. The incidence of herpes zoster increases with age or immunosuppression. The VZV virion consists of a nucleocapsid surrounding a core that contains the linear, double-stranded DNA genome; a protein tegument separates the capsid from the lipid envelope, which incorporates the major viral glycoproteins. VZV is found in a worldwide geographic distribution but is more prevalent in temperate climates. Primary VZV infection elicits immunoglobulin G (IgG), IgM, and IgA antibodies, which bind to many classes of viral proteins. Virus-specific cellular immunity is critical for controlling viral replication in healthy and immunocompromised patients with primary or recurrent VZV infections. Rapid laboratory confirmation of the diagnosis of varicella or herpes zoster, which can be accomplished by detecting viral proteins or DNA, is important to determine the need for antiviral therapy. Acyclovir is licensed for treatment of varicella and herpes zoster, and acyclovir, valacyclovir, and famciclovir are approved for herpes zoster. Passive antibody prophylaxis with varicella-zoster immune globulin is indicated for susceptible high-risk patients exposed to varicella. A live attenuated varicella vaccine (Oka/Merck strain) is now recommended for routine childhood immunization. PMID:8809466

  20. Novel vaccines against influenza viruses

    PubMed Central

    Kang, Sang-Moo; Song, Jae-Min; Compans, Richard W.

    2011-01-01

    Killed and live attenuated influenza virus vaccines are effective in preventing and curbing the spread of influenza epidemics when the strains present in the vaccines are closely matched with the predicted epidemic strains. These vaccines are primarily targeted to induce immunity to the variable major target antigen, hemagglutinin (HA) of influenza virus. However, current vaccines are not effective in preventing the emergence of new pandemic or highly virulent viruses. New approaches are being investigated to develop universal influenza virus vaccines as well as to apply more effective vaccine delivery methods. Conserved vaccine targets including the influenza M2 ion channel protein and HA stalk domains are being developed using recombinant technologies to improve the level of cross protection. In addition, recent studies provide evidence that vaccine supplements can provide avenues to further improve current vaccination. PMID:21968298