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Sample records for enhances virus infectivity

  1. Enhanced infectivity of bluetongue virus in cell culture by centrifugation.

    OpenAIRE

    Sundin, D R; Mecham, J O

    1989-01-01

    The effects of centrifugation of the infection of cell culture with bluetongue virus (BTV) were investigated. Baby hamster kidney cells were infected with BTV with or without centrifugation. Viral antigen was detected by immunofluorescence at 24 h in both centrifuged and noncentrifuged cultures. However, after 24 h of infection, the production of PFU in centrifuged cell cultures was 10- to 20-fold greater than that seen in cultures not centrifuged. In addition, centrifugation enhanced the dir...

  2. Evolutionary enhancement of Zika virus infectivity in Aedes aegypti mosquitoes.

    Science.gov (United States)

    Liu, Yang; Liu, Jianying; Du, Senyan; Shan, Chao; Nie, Kaixiao; Zhang, Rudian; Li, Xiao-Feng; Zhang, Renli; Wang, Tao; Qin, Cheng-Feng; Wang, Penghua; Shi, Pei-Yong; Cheng, Gong

    2017-05-25

    Zika virus (ZIKV) remained obscure until the recent explosive outbreaks in French Polynesia (2013-2014) and South America (2015-2016). Phylogenetic studies have shown that ZIKV has evolved into African and Asian lineages. The Asian lineage of ZIKV was responsible for the recent epidemics in the Americas. However, the underlying mechanisms through which ZIKV rapidly and explosively spread from Asia to the Americas are unclear. Non-structural protein 1 (NS1) facilitates flavivirus acquisition by mosquitoes from an infected mammalian host and subsequently enhances viral prevalence in mosquitoes. Here we show that NS1 antigenaemia determines ZIKV infectivity in its mosquito vector Aedes aegypti, which acquires ZIKV via a blood meal. Clinical isolates from the most recent outbreak in the Americas were much more infectious in mosquitoes than the FSS13025 strain, which was isolated in Cambodia in 2010. Further analyses showed that these epidemic strains have higher NS1 antigenaemia than the FSS13025 strain because of an alanine-to-valine amino acid substitution at residue 188 in NS1. ZIKV infectivity was enhanced by this amino acid substitution in the ZIKV FSS13025 strain in mosquitoes that acquired ZIKV from a viraemic C57BL/6 mouse deficient in type I and II interferon (IFN) receptors (AG6 mouse). Our results reveal that ZIKV evolved to acquire a spontaneous mutation in its NS1 protein, resulting in increased NS1 antigenaemia. Enhancement of NS1 antigenaemia in infected hosts promotes ZIKV infectivity and prevalence in mosquitoes, which could have facilitated transmission during recent ZIKV epidemics.

  3. Enhancement of Ebola Virus Infection via Ficolin-1 Interaction with the Mucin Domain of GP Glycoprotein.

    Science.gov (United States)

    Favier, Anne-Laure; Gout, Evelyne; Reynard, Olivier; Ferraris, Olivier; Kleman, Jean-Philippe; Volchkov, Viktor; Peyrefitte, Christophe; Thielens, Nicole M

    2016-06-01

    Ebola virus infection requires the surface viral glycoprotein to initiate entry into the target cells. The trimeric glycoprotein is a highly glycosylated viral protein which has been shown to interact with host C-type lectin receptors and the soluble complement recognition protein mannose-binding lectin, thereby enhancing viral infection. Similarly to mannose-binding lectin, ficolins are soluble effectors of the innate immune system that recognize particular glycans at the pathogen surface. In this study, we demonstrate that ficolin-1 interacts with the Zaire Ebola virus (EBOV) glycoprotein, and we characterized this interaction by surface plasmon resonance spectroscopy. Ficolin-1 was shown to bind to the viral glycoprotein with a high affinity. This interaction was mediated by the fibrinogen-like recognition domain of ficolin-1 and the mucin-like domain of the viral glycoprotein. Using a ficolin-1 control mutant devoid of sialic acid-binding capacity, we identified sialylated moieties of the mucin domain to be potential ligands on the glycoprotein. In cell culture, using both pseudotyped viruses and EBOV, ficolin-1 was shown to enhance EBOV infection independently of the serum complement. We also observed that ficolin-1 enhanced EBOV infection on human monocyte-derived macrophages, described to be major viral target cells,. Competition experiments suggested that although ficolin-1 and mannose-binding lectin recognized different carbohydrate moieties on the EBOV glycoprotein, the observed enhancement of the infection likely depended on a common cellular receptor/partner. In conclusion, ficolin-1 could provide an alternative receptor-mediated mechanism for enhancing EBOV infection, thereby contributing to viral subversion of the host innate immune system. A specific interaction involving ficolin-1 (M-ficolin), a soluble effector of the innate immune response, and the glycoprotein (GP) of EBOV was identified. Ficolin-1 enhanced virus infection instead of tipping the

  4. Antibody-dependent enhancement of dengue virus infection is inhibited by SA-17, a doxorubicin derivative

    NARCIS (Netherlands)

    Ayala Nunez, Vanesa; Jarupathirun, Patsaporn; Kaptein, Suzanne; Neyts, Johan; Smit, Jolanda

    2013-01-01

    Antibody-dependent enhancement (ADE) is thought to play a critical role in the exacerbation of dengue virus (DENV)-induced disease during a heterologous re-infection. Despite ADE's clinical impact, only a few antiviral compounds have been assessed for their anti-ADE activity. We reported earlier

  5. Nef enhances HIV-1 infectivity via association with the virus assembly complex

    International Nuclear Information System (INIS)

    Qi Mingli; Aiken, Christopher

    2008-01-01

    The HIV-1 accessory protein Nef enhances virus infectivity by facilitating an early post-entry step of infection. Nef acts in the virus producer cell, leading to a beneficial modification to HIV-1 particles. Nef itself is incorporated into HIV-1 particles, where it is cleaved by the viral protease during virion maturation. To probe the role of virion-associated Nef in HIV-1 infection, we generated a fusion protein consisting of the host protein cyclophilin A (CypA) linked to the amino terminus of Nef. The resulting CypA-Nef protein enhanced the infectivity of Nef-defective HIV-1 particles and was specifically incorporated into the virions via association with Gag during particle assembly. Pharmacologic or genetic inhibition of CypA-Nef binding to Gag prevented incorporation of CypA-Nef into virions and inhibited infectivity enhancement. Our results indicate that infectivity enhancement by Nef requires its association with a component of the assembling HIV-1 particle

  6. Flavone Enhances Dengue Virus Type-2 (NGC Strain Infectivity and Replication in Vero Cells

    Directory of Open Access Journals (Sweden)

    Keivan Zandi

    2012-02-01

    Full Text Available This study investigates the effects of 2-phenyl-1-benzopyran-4-one (flavone on DENV-2 infectivity in Vero cells. Virus adsorption and attachment and intracellular virus replication were investigated using a foci forming unit assay (FFUA and quantitative RT-PCR, respectively. Addition of flavone (100 μg/mL significantly increased the number of DENV-2 foci by 35.66% ± 1.52 and 49.66% ± 2.51 when added during and after virus adsorption to the Vero cells, respectively. The average foci size after 4 days of infection increased by 33% ± 2.11 and 89% ± 2.13. The DENV-2 specific RNA copy number in the flavone-treated infected cells increased by 6.41- and 23.1-fold when compared to the mock-treated infected cells. Flavone (100 μg/mL did not promote or inhibit Vero cell proliferation. The CC50 value of flavone against Vero cells was 446 µg/mL. These results suggest that flavone might enhance dengue virus replication by acting antagonistically towards flavonoids known to inhibit dengue virus replication.

  7. Pim kinases are upregulated during Epstein-Barr virus infection and enhance EBNA2 activity

    International Nuclear Information System (INIS)

    Rainio, Eeva-Marja; Ahlfors, Helena; Carter, Kara L.; Ruuska, Marja; Matikainen, Sampsa; Kieff, Elliott; Koskinen, Paeivi J.

    2005-01-01

    Latent Epstein-Barr virus (EBV) infection is strongly associated with B-cell proliferative diseases such as Burkitt's lymphoma. Here we show that the oncogenic serine/threonine kinases Pim-1 and Pim-2 enhance the activity of the viral transcriptional activator EBNA2. During EBV infection of primary B-lymphocytes, the mRNA expression levels of pim genes, especially of pim-2, are upregulated and remain elevated in latently infected B-cell lines. Thus, EBV-induced upregulation of Pim kinases and Pim-stimulated EBNA2 transcriptional activity may contribute to the ability of EBV to immortalize B-cells and predispose them to malignant growth

  8. Chemical modifications of antisense morpholino oligomers enhance their efficacy against Ebola virus infection.

    Science.gov (United States)

    Swenson, Dana L; Warfield, Kelly L; Warren, Travis K; Lovejoy, Candace; Hassinger, Jed N; Ruthel, Gordon; Blouch, Robert E; Moulton, Hong M; Weller, Dwight D; Iversen, Patrick L; Bavari, Sina

    2009-05-01

    Phosphorodiamidate morpholino oligomers (PMOs) are uncharged nucleic acid-like molecules designed to inactivate the expression of specific genes via the antisense-based steric hindrance of mRNA translation. PMOs have been successful at knocking out viral gene expression and replication in the case of acute viral infections in animal models and have been well tolerated in human clinical trials. We propose that antisense PMOs represent a promising class of therapeutic agents that may be useful for combating filoviral infections. We have previously shown that mice treated with a PMO whose sequence is complementary to a region spanning the start codon of VP24 mRNA were protected against lethal Ebola virus challenge. In the present study, we report on the abilities of two additional VP24-specific PMOs to reduce the cell-free translation of a VP24 reporter, to inhibit the in vitro replication of Ebola virus, and to protect mice against lethal challenge when the PMOs are delivered prior to infection. Additionally, structure-activity relationship evaluations were conducted to assess the enhancement of antiviral efficacy associated with PMO chemical modifications that included conjugation with peptides of various lengths and compositions, positioning of conjugated peptides to either the 5' or the 3' terminus, and the conferring of charge modifications by the addition of piperazine moieties. Conjugation with arginine-rich peptides greatly enhanced the antiviral efficacy of VP24-specific PMOs in infected cells and mice during lethal Ebola virus challenge.

  9. Dengue virus infection-enhancing antibody activities against Indonesian strains in inhabitants of central Thailand.

    Science.gov (United States)

    Yamanaka, Atsushi; Oddgun, Duangjai; Chantawat, Nantarat; Okabayashi, Tamaki; Ramasoota, Pongrama; Churrotin, Siti; Kotaki, Tomohiro; Kameoka, Masanori; Soegijanto, Soegeng; Konishi, Eiji

    2016-04-01

    Dengue virus (DENV) infection-enhancing antibodies are a hypothetic factor to increase the dengue disease severity. In this study, we investigated the enhancing antibodies against Indonesian strains of DENV-1-4 in 50 healthy inhabitants of central Thailand (Bangkok and Uthai Thani). Indonesia and Thailand have seen the highest dengue incidence in Southeast Asia. The infection history of each subject was estimated by comparing his/her neutralizing antibody titers against prototype DENV-1-4 strains. To resolve the difficulty in obtaining foreign live viruses for use as assay antigens, we used a recombinant system to prepare single-round infectious dengue viral particles based on viral sequence information. Irrespective of the previously infecting serotype(s), most serum samples showed significantly higher enhancement titers against Indonesian DENV-2 strains than against Thai DENV-2 strains, whereas the opposite effect was observed for the DENV-3 strains. Equivalent enhancing activities were observed against both DENV-1 and DENV-4. These results suggest that the genotype has an impact on enhancing antibody activities against DENV-2 and DENV-3, because the predominant circulating genotypes of each serotype differ between Indonesia and Thailand. Copyright © 2015 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  10. Molecular determinants of dengue virus 2 envelope protein important for virus entry in FcγRIIA-mediated antibody-dependent enhancement of infection

    International Nuclear Information System (INIS)

    Chotiwan, Nunya; Roehrig, John T.; Schlesinger, Jacob J.; Blair, Carol D.; Huang, Claire Y.-H.

    2014-01-01

    Antibody-dependent enhancement (ADE) of infection may cause severe illness in patients suffering a secondary infection by a heterologous dengue virus (DENV) serotype. During ADE of infection, cross-reactive non- or poorly-neutralizing antibodies form infectious virus-Ab complexes with the newly infecting serotype and enhance virus infection by binding to the Fcγ receptors (FcγR) on FcγR-bearing cells. In this study, we determined that molecular determinants of DENV2 envelope protein critical for virus entry during non-ADE infection are also required for ADE infection mediated by FcγRIIA, and binding of virus-Ab complexes with FcγRIIA alone is not sufficient for ADE of infection. The FcγRIIA mainly plays an auxiliary role in concentrating the virus–Ab complex to the cell surface, and other primary cellular receptors are required for virus entry. Understanding the viral entry pathway in ADE of DENV infection will greatly facilitate rational designs of anti-viral therapeutics against severe dengue disease associated with ADE. - Highlights: • KKK305/307/310 in DENV2 E-DIII is critical for virus attachment in ADE and non-ADE infection. • Binding of DENV2–Ab complex with FcγRII alone is not sufficient for virus entry in ADE infection. • Other primary receptors were required for DENV2 internalization during FcγRII–mediated ADE. • G104 and L135 of DENV2 E are critical for virus-mediated membrane fusion. • DENV2 virus-mediated membrane fusion is required for both ADE and non-ADE infection

  11. Molecular determinants of dengue virus 2 envelope protein important for virus entry in FcγRIIA-mediated antibody-dependent enhancement of infection

    Energy Technology Data Exchange (ETDEWEB)

    Chotiwan, Nunya; Roehrig, John T. [Arboviral Diseases Branch, Division of Vector-Borne Disease, Centers for Disease Control and Prevention, Fort Collins, CO 80521 (United States); Schlesinger, Jacob J. [Department of Medicine, University of Rochester, Rochester, NY 14642 (United States); Blair, Carol D. [Arthropod-borne and Infectious Diseases Laboratory, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO 80523 (United States); Huang, Claire Y.-H., E-mail: yxh0@cdc.gov [Arboviral Diseases Branch, Division of Vector-Borne Disease, Centers for Disease Control and Prevention, Fort Collins, CO 80521 (United States)

    2014-05-15

    Antibody-dependent enhancement (ADE) of infection may cause severe illness in patients suffering a secondary infection by a heterologous dengue virus (DENV) serotype. During ADE of infection, cross-reactive non- or poorly-neutralizing antibodies form infectious virus-Ab complexes with the newly infecting serotype and enhance virus infection by binding to the Fcγ receptors (FcγR) on FcγR-bearing cells. In this study, we determined that molecular determinants of DENV2 envelope protein critical for virus entry during non-ADE infection are also required for ADE infection mediated by FcγRIIA, and binding of virus-Ab complexes with FcγRIIA alone is not sufficient for ADE of infection. The FcγRIIA mainly plays an auxiliary role in concentrating the virus–Ab complex to the cell surface, and other primary cellular receptors are required for virus entry. Understanding the viral entry pathway in ADE of DENV infection will greatly facilitate rational designs of anti-viral therapeutics against severe dengue disease associated with ADE. - Highlights: • KKK305/307/310 in DENV2 E-DIII is critical for virus attachment in ADE and non-ADE infection. • Binding of DENV2–Ab complex with FcγRII alone is not sufficient for virus entry in ADE infection. • Other primary receptors were required for DENV2 internalization during FcγRII–mediated ADE. • G104 and L135 of DENV2 E are critical for virus-mediated membrane fusion. • DENV2 virus-mediated membrane fusion is required for both ADE and non-ADE infection.

  12. Cordycepin enhances Epstein-Barr virus lytic infection and Epstein-Barr virus-positive tumor treatment efficacy by doxorubicin.

    Science.gov (United States)

    Du, Yinping; Yu, Jieshi; Du, Li; Tang, Jun; Feng, Wen-Hai

    2016-07-01

    The consistent latent presence of Epstein-Barr virus (EBV) in tumor cells offers potential for virus-targeted therapies. The switch from the latent form of EBV to the lytic form in tumor cells can lead to tumor cell lysis. In this study, we report that a natural small molecule compound, cordycepin, can induce lytic EBV infection in tumor cells. Subsequently, we demonstrate that cordycepin can enhance EBV reactivating capacity and EBV-positive tumor cell killing ability of low dose doxorubicin. The combination of cordycepin and doxorubicin phosphorylates CCAAT/enhancer binding protein β (C/EBPβ) through protein kinase C (PKC)-p38 mitogen activated protein kinases (p38 MAPK) signaling pathway, and C/EBPβ is required for the activation of lytic EBV infection. Most importantly, an in vivo experiment demonstrates that the combination of cordycepin and doxorubicin is more effective in inhibiting tumor growth in SCID mice than is doxorubicin alone. Our findings establish that cordycepin can enhance the efficacy of conventional chemotherapy for treatment of EBV-positive tumors. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  13. Wolbachia enhances West Nile virus (WNV infection in the mosquito Culex tarsalis.

    Directory of Open Access Journals (Sweden)

    Brittany L Dodson

    2014-07-01

    Full Text Available Novel strategies are required to control mosquitoes and the pathogens they transmit. One attractive approach involves maternally inherited endosymbiotic Wolbachia bacteria. After artificial infection with Wolbachia, many mosquitoes become refractory to infection and transmission of diverse pathogens. We evaluated the effects of Wolbachia (wAlbB strain on infection, dissemination and transmission of West Nile virus (WNV in the naturally uninfected mosquito Culex tarsalis, which is an important WNV vector in North America. After inoculation into adult female mosquitoes, Wolbachia reached high titers and disseminated widely to numerous tissues including the head, thoracic flight muscles, fat body and ovarian follicles. Contrary to other systems, Wolbachia did not inhibit WNV in this mosquito. Rather, WNV infection rate was significantly higher in Wolbachia-infected mosquitoes compared to controls. Quantitative PCR of selected innate immune genes indicated that REL1 (the activator of the antiviral Toll immune pathway was down regulated in Wolbachia-infected relative to control mosquitoes. This is the first observation of Wolbachia-induced enhancement of a human pathogen in mosquitoes, suggesting that caution should be applied before releasing Wolbachia-infected insects as part of a vector-borne disease control program.

  14. Modulation of Dengue/Zika Virus Pathogenicity by Antibody-Dependent Enhancement and Strategies to Protect Against Enhancement in Zika Virus Infection

    Directory of Open Access Journals (Sweden)

    Rekha Khandia

    2018-04-01

    Full Text Available Antibody-dependent enhancement (ADE is a phenomenon in which preexisting poorly neutralizing antibodies leads to enhanced infection. It is a serious concern with mosquito-borne flaviviruses such as Dengue virus (DENV and Zika virus (ZIKV. In vitro experimental evidences have indicated the preventive, as well as a pathogenicity-enhancing role, of preexisting DENV antibodies in ZIKV infections. ADE has been confirmed in DENV but not ZIKV infections. Principally, the Fc region of the anti-DENV antibody binds with the fragment crystallizable gamma receptor (FcγR, and subsequent C1q interactions and immune effector functions are responsible for the ADE. In contrast to normal DENV infections, with ADE in DENV infections, inhibition of STAT1 phosphorylation and a reduction in IRF-1 gene expression, NOS2 levels, and RIG-1 and MDA-5 expression levels occurs. FcγRIIA is the most permissive FcγR for DENV-ADE, and under hypoxic conditions, hypoxia-inducible factor-1 alpha transcriptionally enhances expression levels of FcγRIIA, which further enhances ADE. To produce therapeutic antibodies with broad reactivity to different DENV serotypes, as well as to ZIKV, bispecific antibodies, Fc region mutants, modified Fc regions, and anti-idiotypic antibodies may be engineered. An in-depth understanding of the immunological and molecular mechanisms of DENV-ADE of ZIKV pathogenicity will be useful for the design of common and safe therapeutics and prophylactics against both viral pathogens. The present review discusses the role of DENV antibodies in modulating DENV/ZIKV pathogenicity/infection and strategies to counter ADE to protect against Zika infection.

  15. Defining New Therapeutics Using a More Immunocompetent Mouse Model of Antibody-Enhanced Dengue Virus Infection.

    Science.gov (United States)

    Pinto, Amelia K; Brien, James D; Lam, Chia-Ying Kao; Johnson, Syd; Chiang, Cindy; Hiscott, John; Sarathy, Vanessa V; Barrett, Alan D; Shresta, Sujan; Diamond, Michael S

    2015-09-15

    With over 3.5 billion people at risk and approximately 390 million human infections per year, dengue virus (DENV) disease strains health care resources worldwide. Previously, we and others established models for DENV pathogenesis in mice that completely lack subunits of the receptors (Ifnar and Ifngr) for type I and type II interferon (IFN) signaling; however, the utility of these models is limited by the pleotropic effect of these cytokines on innate and adaptive immune system development and function. Here, we demonstrate that the specific deletion of Ifnar expression on subsets of murine myeloid cells (LysM Cre(+) Ifnar(flox/flox) [denoted as Ifnar(f/f) herein]) resulted in enhanced DENV replication in vivo. The administration of subneutralizing amounts of cross-reactive anti-DENV monoclonal antibodies to LysM Cre(+) Ifnar(f/f) mice prior to infection with DENV serotype 2 or 3 resulted in antibody-dependent enhancement (ADE) of infection with many of the characteristics associated with severe DENV disease in humans, including plasma leakage, hypercytokinemia, liver injury, hemoconcentration, and thrombocytopenia. Notably, the pathogenesis of severe DENV-2 or DENV-3 infection in LysM Cre(+) Ifnar(f/f) mice was blocked by pre- or postexposure administration of a bispecific dual-affinity retargeting molecule (DART) or an optimized RIG-I receptor agonist that stimulates innate immune responses. Our findings establish a more immunocompetent animal model of ADE of infection with multiple DENV serotypes in which disease is inhibited by treatment with broad-spectrum antibody derivatives or innate immune stimulatory agents. Although dengue virus (DENV) infects hundreds of millions of people annually and results in morbidity and mortality on a global scale, there are no approved antiviral treatments or vaccines. Part of the difficulty in evaluating therapeutic candidates is the lack of small animal models that are permissive to DENV and recapitulate the clinical features

  16. Streptococcus pneumoniae enhances human respiratory syncytial virus infection in vitro and in vivo

    NARCIS (Netherlands)

    D.T. Nguyen (Tien); R.P.L. Louwen (Rogier); Elberse, K. (Karin); G. van Amerongen (Geert); S. Yüksel (Selma); A. Luijendijk (Ad); A.D.M.E. Osterhaus (Albert); W.P. Duprex (William Paul); R.L. de Swart (Rik)

    2015-01-01

    textabstractHuman respiratory syncytial virus (HRSV) and Streptococcus pneumoniae are important causative agents of respiratory tract infections. Both pathogens are associated with seasonal disease outbreaks in the pediatric population, and can often be detected simultaneously in infants

  17. Molecular mechanisms of dengue virus infection : cell tropism, antibody-dependent enhancement, and cytokines

    NARCIS (Netherlands)

    Flipse, Jacobus

    2015-01-01

    Dengue is the most prevalent mosquito-borne viral disease in humans. Although most infections occur in the (sub)tropical areas, recent outbreaks in Italy and Madeira indicate that the virus is spreading into Europe. Despite its relevance, no vaccine or medications are available against this virus.

  18. Viruses infecting reptiles.

    Science.gov (United States)

    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.

  19. Viruses Infecting Reptiles

    Directory of Open Access Journals (Sweden)

    Rachel E. Marschang

    2011-11-01

    Full Text Available 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.

  20. Respiratory syncytial virus infection enhances Pseudomonas aeruginosa biofilm growth through dysregulation of nutritional immunity.

    Science.gov (United States)

    Hendricks, Matthew R; Lashua, Lauren P; Fischer, Douglas K; Flitter, Becca A; Eichinger, Katherine M; Durbin, Joan E; Sarkar, Saumendra N; Coyne, Carolyn B; Empey, Kerry M; Bomberger, Jennifer M

    2016-02-09

    Clinical observations link respiratory virus infection and Pseudomonas aeruginosa colonization in chronic lung disease, including cystic fibrosis (CF) and chronic obstructive pulmonary disease. The development of P. aeruginosa into highly antibiotic-resistant biofilm communities promotes airway colonization and accounts for disease progression in patients. Although clinical studies show a strong correlation between CF patients' acquisition of chronic P. aeruginosa infections and respiratory virus infection, little is known about the mechanism by which chronic P. aeruginosa infections are initiated in the host. Using a coculture model to study the formation of bacterial biofilm formation associated with the airway epithelium, we show that respiratory viral infections and the induction of antiviral interferons promote robust secondary P. aeruginosa biofilm formation. We report that the induction of antiviral IFN signaling in response to respiratory syncytial virus (RSV) infection induces bacterial biofilm formation through a mechanism of dysregulated iron homeostasis of the airway epithelium. Moreover, increased apical release of the host iron-binding protein transferrin during RSV infection promotes P. aeruginosa biofilm development in vitro and in vivo. Thus, nutritional immunity pathways that are disrupted during respiratory viral infection create an environment that favors secondary bacterial infection and may provide previously unidentified targets to combat bacterial biofilm formation.

  1. Neuraminidase treatment of respiratory syncytial virus-infected cells or virions, but not target cells, enhances cell-cell fusion and infection

    International Nuclear Information System (INIS)

    Barretto, Naina; Hallak, Louay K.; Peeples, Mark E.

    2003-01-01

    Respiratory syncytial virus (RSV) infection of HeLa cells induces fusion, but transient expression of the three viral glycoproteins induces fusion poorly, if at all. We found that neuraminidase treatment of RSV-infected cells to remove sialic acid (SA) increases fusion dramatically and that the same treatment of transiently transfected cells expressing the three viral glycoproteins, or even cells expressing the fusion (F) protein alone, results in easily detectable fusion. Neuraminidase treatment of the effector cells, expressing the viral glycoproteins, enhanced fusion while treatment of the target cells did not. Likewise, infectivity was increased by treating virions with neuraminidase, but not by treating target cells. Reduction of charge repulsion by removal of the negatively charged SA is unlikely to explain this effect, since removal of negative charges from either membrane would reduce charge repulsion. Infection with neuraminidase-treated virus remained heparan-sulfate-dependent, indicating that a novel attachment mechanism is not revealed by SA removal. Interestingly, neuraminidase enhancement of RSV infectivity was less pronounced in a virus expressing both the G and the F glycoproteins, compared to virus expressing only the F glycoprotein, possibly suggesting that the G protein sterically hinders access of the neuraminidase to its fusion-enhancing target

  2. Ultraviolet enhanced reactivation of a human virus: effect of delayed infection

    International Nuclear Information System (INIS)

    Bockstahler, L.E.; Lytle, C.D.; Stafford, J.E.; Haynes, K.F.

    1976-01-01

    The ability of UV-irradiated herpes simplex virus to form plaques was examined in monolayers of CV-1 monkey kidney cells preexposed to UV radiation at different intervals before virus assay. From analysis of UV reactivation (Weigle reactivation) curves it was found that as the interval between cell UV irradiation (0-20 J/m 2 ) and initiation of the virus assay was increased over a period of five days, (1) the capacity of the cells to support unirradiated virus plaque formation, which was decreased immediately following UV exposure of the monolayers, increased and returned to approximately normal levels within five days, and (2) at five days an exponential increase was observed in the relative plaque formation of irradiated virus as a function of UV dose to the monolayers. For high UV fluence (20 J/m 2 ) to the cells, the relative plaque formation by the UV-irradiated virus at five days was about 10-fold higher than that obtained from assay on unirradiated cells. This enhancement in plaque formation is interpreted as a delayed expression of Weigle reactivation. The amount of enhancement resulting from this delayed reactivation was several fold greater than that produced by the Weigle reactivation which occurred when irradiated herpes virus was assayed immediately following cell irradiation

  3. Vaccination with experimental feline immunodeficiency virus vaccines, based on autologous infected cells, elicits enhancement of homologous challenge infection

    NARCIS (Netherlands)

    J.A. Karlas (Jos); C.H.J. Siebelink (Kees); M.A. Peer; W. Huisman (Willem); A.M. Cuisinier; G.F. Rimmelzwaan (Guus); A.D.M.E. Osterhaus (Albert)

    1999-01-01

    textabstractCats were vaccinated with fixed autologous feline immunodeficiency virus (FIV)-infected cells in order to present viral proteins to the immune system of individual cats in an MHC-matched fashion. Upon vaccination, a humoral response against Gag was induced. Furthermore,

  4. Lectin-dependent enhancement of Ebola virus infection via soluble and transmembrane C-type lectin receptors.

    Directory of Open Access Journals (Sweden)

    Matthew Brudner

    Full Text Available Mannose-binding lectin (MBL is a key soluble effector of the innate immune system that recognizes pathogen-specific surface glycans. Surprisingly, low-producing MBL genetic variants that may predispose children and immunocompromised individuals to infectious diseases are more common than would be expected in human populations. Since certain immune defense molecules, such as immunoglobulins, can be exploited by invasive pathogens, we hypothesized that MBL might also enhance infections in some circumstances. Consequently, the low and intermediate MBL levels commonly found in human populations might be the result of balancing selection. Using model infection systems with pseudotyped and authentic glycosylated viruses, we demonstrated that MBL indeed enhances infection of Ebola, Hendra, Nipah and West Nile viruses in low complement conditions. Mechanistic studies with Ebola virus (EBOV glycoprotein pseudotyped lentiviruses confirmed that MBL binds to N-linked glycan epitopes on viral surfaces in a specific manner via the MBL carbohydrate recognition domain, which is necessary for enhanced infection. MBL mediates lipid-raft-dependent macropinocytosis of EBOV via a pathway that appears to require less actin or early endosomal processing compared with the filovirus canonical endocytic pathway. Using a validated RNA interference screen, we identified C1QBP (gC1qR as a candidate surface receptor that mediates MBL-dependent enhancement of EBOV infection. We also identified dectin-2 (CLEC6A as a potentially novel candidate attachment factor for EBOV. Our findings support the concept of an innate immune haplotype that represents critical interactions between MBL and complement component C4 genes and that may modify susceptibility or resistance to certain glycosylated pathogens. Therefore, higher levels of native or exogenous MBL could be deleterious in the setting of relative hypocomplementemia which can occur genetically or because of immunodepletion

  5. Lectin-dependent enhancement of Ebola virus infection via soluble and transmembrane C-type lectin receptors.

    Science.gov (United States)

    Brudner, Matthew; Karpel, Marshall; Lear, Calli; Chen, Li; Yantosca, L Michael; Scully, Corinne; Sarraju, Ashish; Sokolovska, Anna; Zariffard, M Reza; Eisen, Damon P; Mungall, Bruce A; Kotton, Darrell N; Omari, Amel; Huang, I-Chueh; Farzan, Michael; Takahashi, Kazue; Stuart, Lynda; Stahl, Gregory L; Ezekowitz, Alan B; Spear, Gregory T; Olinger, Gene G; Schmidt, Emmett V; Michelow, Ian C

    2013-01-01

    Mannose-binding lectin (MBL) is a key soluble effector of the innate immune system that recognizes pathogen-specific surface glycans. Surprisingly, low-producing MBL genetic variants that may predispose children and immunocompromised individuals to infectious diseases are more common than would be expected in human populations. Since certain immune defense molecules, such as immunoglobulins, can be exploited by invasive pathogens, we hypothesized that MBL might also enhance infections in some circumstances. Consequently, the low and intermediate MBL levels commonly found in human populations might be the result of balancing selection. Using model infection systems with pseudotyped and authentic glycosylated viruses, we demonstrated that MBL indeed enhances infection of Ebola, Hendra, Nipah and West Nile viruses in low complement conditions. Mechanistic studies with Ebola virus (EBOV) glycoprotein pseudotyped lentiviruses confirmed that MBL binds to N-linked glycan epitopes on viral surfaces in a specific manner via the MBL carbohydrate recognition domain, which is necessary for enhanced infection. MBL mediates lipid-raft-dependent macropinocytosis of EBOV via a pathway that appears to require less actin or early endosomal processing compared with the filovirus canonical endocytic pathway. Using a validated RNA interference screen, we identified C1QBP (gC1qR) as a candidate surface receptor that mediates MBL-dependent enhancement of EBOV infection. We also identified dectin-2 (CLEC6A) as a potentially novel candidate attachment factor for EBOV. Our findings support the concept of an innate immune haplotype that represents critical interactions between MBL and complement component C4 genes and that may modify susceptibility or resistance to certain glycosylated pathogens. Therefore, higher levels of native or exogenous MBL could be deleterious in the setting of relative hypocomplementemia which can occur genetically or because of immunodepletion during active

  6. Oral intake of Lactobacillus rhamnosus M21 enhances the survival rate of mice lethally infected with influenza virus.

    Science.gov (United States)

    Song, Jeong Ah; Kim, Hee Joo; Hong, Seong Keun; Lee, Dong Hoon; Lee, Sang Won; Song, Chang Seon; Kim, Ki Taek; Choi, In Soo; Lee, Joong Bok; Park, Seung Yong

    2016-02-01

    Influenza viruses cause acute respiratory disease. Because of the high genetic variability of viruses, effective vaccines and antiviral agents are limited. Considering the fact that the site of influenza virus entry is the mucosa of the upper respiratory tract, probiotics that can enhance mucosal immunity as well as systemic immunity could be an important source of treatment against influenza infection. Mice were fed with Lactobacillus rhamnosus M21 or skim milk and were challenged with influenza virus. The resulting survival rate, lung inflammation, and changes in the cytokine and secretory immunoglobulin A (sIgA) levels were examined. Because of infection (influenza virus), all the mice in the control group and 60% of the mice in the L. rhamnosus M21 group died; however, the remaining 40% of the mice fed with L. rhamnosus M21 survived the infection. Pneumonia was severe in the control group but moderate in the group treated with L. rhamnosus M21. Although there were no significant changes in the proinflammatory cytokines in the lung lysates of mice collected from both groups, levels of interferon-γ and interleukin-2, which are representative cytokines of type I helper T cells, were significantly increased in the L. rhamnosus M21-treated group. An increase in sIgA as well as the diminution of inflammatory cells in bronchoalveolar lavage fluid was also observed in the L. rhamnosus M21-treated group. These results demonstrate that orally administered L. rhamnosus M21 activates humoral as well as cellular immune responses, conferring increased resistance to the host against influenza virus infection. Copyright © 2014. Published by Elsevier B.V.

  7. Blocking of PDL-1 interaction enhances primary and secondary CD8 T cell response to herpes simplex virus-1 infection.

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    Rudragouda Channappanavar

    Full Text Available The blocking of programmed death ligand-1 (PDL-1 has been shown to enhance virus-specific CD8 T cell function during chronic viral infections. Though, how PDL-1 blocking at the time of priming affects the quality of CD8 T cell response to acute infections is not well understood and remains controversial. This report demonstrates that the magnitude of the primary and secondary CD8 T cell responses to herpes simplex virus-1 (HSV-1 infection is subject to control by PDL-1. Our results showed that after footpad HSV-1 infection, PD-1 expression increases on immunodominant SSIEFARL peptide specific CD8 T cells. Additionally, post-infection, the level of PDL-1 expression also increases on CD11c+ dendritic cells. Intraperitoneal administration of anti-PDL-1 monoclonal antibody given one day prior to and three days after cutaneous HSV-1 infection, resulted in a marked increase in effector and memory CD8 T cell response to SSIEFARL peptide. This was shown by measuring the quantity and quality of SSIEFARL-specific CD8 T cells by making use of ex-vivo assays that determine antigen specific CD8 T cell function, such as intracellular cytokine assay, degranulation assay to measure cytotoxicity and viral clearance. Our results are discussed in terms of the beneficial effects of blocking PDL-1 interactions, while giving prophylactic vaccines, to generate a more effective CD8 T cell response to viral infection.

  8. Herpes simplex virus downregulation of secretory leukocyte protease inhibitor enhances human papillomavirus type 16 infection.

    Science.gov (United States)

    Skeate, Joseph G; Porras, Tania B; Woodham, Andrew W; Jang, Julie K; Taylor, Julia R; Brand, Heike E; Kelly, Thomas J; Jung, Jae U; Da Silva, Diane M; Yuan, Weiming; Kast, W Martin

    2016-02-01

    Herpes simplex virus (HSV) was originally implicated in the aetiology of cervical cancer, and although high-risk human papillomavirus (HPV) is now the accepted causative agent, the epidemiological link between HSV and HPV-associated cancers persists. The annexin A2 heterotetramer (A2t) has been shown to mediate infectious HPV type 16 (HPV16) uptake by human keratinocytes, and secretory leukocyte protease inhibitor (SLPI), an endogenous A2t ligand, inhibits HPV16 uptake and infection. Interestingly, HSV infection induces a sustained downregulation of SLPI in epithelial cells, which we hypothesized promotes HPV16 infection through A2t. Here, we show that in vitro infection of human keratinocytes with HSV-1 or HSV-2, but not with an HSV-1 ICP4 deletion mutant that does not downregulate SLPI, leads to a >70% reduction of SLPI mRNA and a >60% decrease in secreted SLPI protein. Consequently, we observed a significant increase in the uptake of HPV16 virus-like particles and gene transduction by HPV16 pseudovirions (two- and 2.5-fold, respectively) in HSV-1- and HSV-2-infected human keratinocyte cell cultures compared with uninfected cells, whereas exogenously added SLPI reversed this effect. Using a SiMPull (single-molecule pulldown) assay, we demonstrated that endogenously secreted SLPI interacts with A2t on epithelial cells in an autocrine/paracrine manner. These results suggested that ongoing HSV infection and resultant downregulation of local levels of SLPI may impart a greater susceptibility for keratinocytes to HPV16 infection through the host cell receptor A2t, providing a mechanism that may, in part, provide an explanation for the aetiological link between HSV and HPV-associated cancers.

  9. Knockdown of autophagy enhances innate immune response in hepatitis C virus infected hepatocytes

    Science.gov (United States)

    Shrivastava, Shubham; Raychoudhuri, Amit; Steele, Robert; Ray, Ranjit; Ray, Ratna B.

    2010-01-01

    The role of autophagy in disease pathogenesis following viral infection is beginning to be elucidated. We have previously reported that hepatitis C virus (HCV) infection in hepatocytes induces autophagy. However, the biological significance of HCV induced autophagy has not been clarified. Autophagy has recently been identified as a novel component of innate immune system against viral infection. In the present study, we have shown that knockdown of autophagy related protein Beclin1 or ATG7 in immortalized human hepatocytes (IHH) inhibited HCV growth. Beclin1 or ATG7 knockdown IHH when infected with HCV exhibited an increased expression of IFN-β, OAS-1, IFN-α and IFI27 mRNAs of the interferon signaling pathways as compared to infection of control IHH. Subsequent study demonstrated that HCV infection in autophagy impaired IHH displayed caspase activation, PARP cleavage and apoptotic cell death. Conclusion The disruption of autophagy machinery in HCV infected hepatocytes activated IFN signaling pathway, and induced apoptosis. Together, these results suggest that HCV induced autophagy impairs innate immune response. PMID:21274862

  10. Curing of foot-and-mouth disease virus from persistently infected cells by ribavirin involves enhanced mutagenesis

    International Nuclear Information System (INIS)

    Airaksinen, Antero; Pariente, Nonia; Menendez-Arias, Luis; Domingo, Esteban

    2003-01-01

    BHK-21 cells persistently infected with foot-and-mouth disease virus (FMDV) can be cured of virus by treatment with the antiviral nucleoside analogue ribavirin. To study whether the process involved an increase in the number of mutations in the mutant spectrum of the viral population, viral genomes were cloned from persistently infected cells treated or untreated with ribavirin. An increase of up to 10-fold in mutation frequencies associated with ribavirin treatment was observed in the viral genomes from the treated cultures as compared with parallel, untreated cultures. To address the possible mechanisms of enhanced mutagenesis, we investigated the mutagenic effects of ribavirin together with guanosine, and mycophenolic acid in the presence or absence of guanosine. Changes in the intracellular nucleotide concentrations were determined for all treatments. The results suggest that the increased mutation frequencies were not dependent on nucleotide pool imbalances or due to selection of preexisting genomes but they were produced by a mutagenic action of ribavirin

  11. Enhanced mutagenesis of UV-irradiated simian virus 40 occurs in mitomycin C-treated host cells only at a low multiplicity of infection

    International Nuclear Information System (INIS)

    Sarasin, A.; Benoit, A.

    1986-01-01

    Treatment of monkey kidney cells with mitomycin C (MMC) 24 h prior to infection with UV-irradiated simian virus 40 (SV40) enhanced both virus survival and virus mutagenesis. The use of SV40 as a biological probe has been taken as an easy method to analyse SOS response of mammalian cells to the stress caused by DNA damage or inhibition of DNA replication. The mutation assay we used was based on the reversion from a temperature-sensitive phenotype (tsA58 mutant) to a wild-type phenotype. The optimal conditions for producing enhanced survival and mutagenesis in the virus progeny were determined with regard to the multiplicity of infection (MOI). Results showed that the level of enhanced mutagenesis observed for UV-irradiated virus grown in MMC-treated cells was an inverse function of the MOI, while enhanced survival was observed at nearly the same level regardless of the MOI. For the unirradiated virus, almost no increase in the mutation of virus progeny issued from MMC-treated cells was observed, while a small amount of enhanced virus survival was obtained. These results show that enhanced virus mutagenesis and enhanced virus survival can be dissociated under some experimental conditions. Enhanced virus mutagenesis, analogous to the error-prone replication of phages in SOS-induced bacteria, was observed, at least for SV40, only when DNA of both virus and host cells was damaged and when infection occurred with a small number of viral particles. We therefore hypothesize that an error-prone replication mode of UV-damaged templates is observed in induced monkey kidney cells

  12. Zika virus infection.

    Science.gov (United States)

    Pougnet, Laurence; Thill, Chloé; Pougnet, Richard; Auvinet, Henri; Giacardi, Christophe; Drouillard, Isabelle

    2016-12-01

    A 21-year old woman from New-Caledonia had 40 ̊C fever with vomiting, arthralgia, myalgia, and measles-like rash. Etiological analyses showed primary infection with Zika virus. Because of severe clinical presentation, she was hospitalized in the intensive care unit of the Brest military Hospital. Zika virus is mainly transmitted by Aedes mosquitoes. If they settle in Metropolitan France, Zika virus might also spread there.

  13. [ZIKA--VIRUS INFECTION].

    Science.gov (United States)

    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.

  14. Viruses infecting marine molluscs.

    Science.gov (United States)

    Arzul, Isabelle; Corbeil, Serge; Morga, Benjamin; Renault, Tristan

    2017-07-01

    Although a wide range of viruses have been reported in marine molluscs, most of these reports rely on ultrastructural examination and few of these viruses have been fully characterized. The lack of marine mollusc cell lines restricts virus isolation capacities and subsequent characterization works. Our current knowledge is mostly restricted to viruses affecting farmed species such as oysters Crassostrea gigas, abalone Haliotis diversicolor supertexta or the scallop Chlamys farreri. Molecular approaches which are needed to identify virus affiliation have been carried out for a small number of viruses, most of them belonging to the Herpesviridae and birnaviridae families. These last years, the use of New Generation Sequencing approach has allowed increasing the number of sequenced viral genomes and has improved our capacity to investigate the diversity of viruses infecting marine molluscs. This new information has in turn allowed designing more efficient diagnostic tools. Moreover, the development of experimental infection protocols has answered some questions regarding the pathogenesis of these viruses and their interactions with their hosts. Control and management of viral diseases in molluscs mostly involve active surveillance, implementation of effective bio security measures and development of breeding programs. However factors triggering pathogen development and the life cycle and status of the viruses outside their mollusc hosts still need further investigations. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Enhancement of Herpes Simplex Virus (HSV Infection by Seminal Plasma and Semen Amyloids Implicates a New Target for the Prevention of HSV Infection

    Directory of Open Access Journals (Sweden)

    Lilith Torres

    2015-04-01

    Full Text Available Human herpesviruses cause different infectious diseases, resulting in world-wide health problems. Sexual transmission is a major route for the spread of both herpes simplex virus-1 (HSV-1 and -2. Semen plays an important role in carrying the viral particle that invades the vaginal or rectal mucosa and, thereby, initiates viral replication. Previously, we demonstrated that the amyloid fibrils semenogelin (SEM and semen-derived enhancer of viral infection (SEVI, and seminal plasma (SP augment cytomegalovirus infection (Tang et al., J. Virol 2013. Whether SEM or SEVI amyloids or SP could also enhance other herpesvirus infections has not been examined. In this study, we found that the two amyloids as well as SP strongly enhance both HSV-1 and -2 infections in cell culture. Along with SP, SEM and SEVI amyloids enhanced viral entry and increased infection rates by more than 10-fold, as assessed by flow cytometry assay and fluorescence microscopy. Viral replication was increased by about 50- to 100-fold. Moreover, viral growth curve assays showed that SEM and SEVI amyloids, as well as SP, sped up the kinetics of HSV replication such that the virus reached its replicative peak more quickly. The interactions of SEM, SEVI, and SP with HSVs are direct. Furthermore, we discovered that the enhancing effects of SP, SEM, and SEVI can be significantly reduced by heparin, a sulfated polysaccharide with an anionic charge. It is probable that heparin abrogates said enhancing effects by interfering with the interaction of the viral particle and the amyloids, which interaction results in the binding of the viral particles and both SEM and SEVI.

  16. Anti-Idiotypic Antibodies Specific to prM Monoantibody Prevent Antibody Dependent Enhancement of Dengue Virus Infection

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    Miao Wang

    2017-05-01

    Full Text Available Dengue virus (DENV co-circulates as four serotypes (DENV1-4. Primary infection only leads to self-limited dengue fever. But secondary infection with another serotype carries a higher risk of increased disease severity, causing life-threatening dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS. Serotype cross-reactive antibodies facilitate DENV infection in Fc-receptor-bearing cells by promoting virus entry via Fcγ receptors (FcγR, a process known as antibody dependent enhancement (ADE. Most studies suggested that enhancing antibodies were mainly specific to the structural premembrane protein (prM of DENV. However, there is still no effective drugs or vaccines to prevent ADE. In this study, we firstly confirmed that both DENV-2 infected human sera (anti-DENV-2 and DENV-2 prM monoclonal antibody (prM mAb could significantly enhance DENV-1 infection in K562 cells. Then we developed anti-idiotypic antibodies (prM-AIDs specific to prM mAb by immunizing of Balb/c mice. Results showed that these polyclonal antibodies can dramatically reduce ADE phenomenon of DENV-1 infection in K562 cells. To further confirm the anti-ADE effect of prM-AIDs in vivo, interferon-α and γ receptor-deficient mice (AG6 were used as the mouse model for DENV infection. We found that administration of DENV-2 prM mAb indeed caused a higher DENV-1 titer as well as interleukin-10 (IL-10 and alaninea minotransferase (ALT in mice infected with DENV-1, similar to clinical ADE symptoms. But when we supplemented prM-AIDs to DENV-1 challenged AG6 mice, the viral titer, IL-10 and ALT were obviously decreased to the negative control level. Of note, the number of platelets in peripheral blood of prM-AIDs group were significantly increased at day 3 post infection with DENV-1 compared that of prM-mAb group. These results confirmed that our prM-AIDs could prevent ADE not only in vitro but also in vivo, suggested that anti-idiotypic antibodies might be a new choice to be considered to

  17. Anti-Idiotypic Antibodies Specific to prM Monoantibody Prevent Antibody Dependent Enhancement of Dengue Virus Infection.

    Science.gov (United States)

    Wang, Miao; Yang, Fan; Huang, Dana; Huang, Yalan; Zhang, Xiaomin; Wang, Chao; Zhang, Shaohua; Zhang, Renli

    2017-01-01

    Dengue virus (DENV) co-circulates as four serotypes (DENV1-4). Primary infection only leads to self-limited dengue fever. But secondary infection with another serotype carries a higher risk of increased disease severity, causing life-threatening dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS). Serotype cross-reactive antibodies facilitate DENV infection in Fc-receptor-bearing cells by promoting virus entry via Fcγ receptors (FcγR), a process known as antibody dependent enhancement (ADE). Most studies suggested that enhancing antibodies were mainly specific to the structural premembrane protein (prM) of DENV. However, there is still no effective drugs or vaccines to prevent ADE. In this study, we firstly confirmed that both DENV-2 infected human sera (anti-DENV-2) and DENV-2 prM monoclonal antibody (prM mAb) could significantly enhance DENV-1 infection in K562 cells. Then we developed anti-idiotypic antibodies (prM-AIDs) specific to prM mAb by immunizing of Balb/c mice. Results showed that these polyclonal antibodies can dramatically reduce ADE phenomenon of DENV-1 infection in K562 cells. To further confirm the anti-ADE effect of prM-AIDs in vivo , interferon-α and γ receptor-deficient mice (AG6) were used as the mouse model for DENV infection. We found that administration of DENV-2 prM mAb indeed caused a higher DENV-1 titer as well as interleukin-10 (IL-10) and alaninea minotransferase (ALT) in mice infected with DENV-1, similar to clinical ADE symptoms. But when we supplemented prM-AIDs to DENV-1 challenged AG6 mice, the viral titer, IL-10 and ALT were obviously decreased to the negative control level. Of note, the number of platelets in peripheral blood of prM-AIDs group were significantly increased at day 3 post infection with DENV-1 compared that of prM-mAb group. These results confirmed that our prM-AIDs could prevent ADE not only in vitro but also in vivo , suggested that anti-idiotypic antibodies might be a new choice to be considered to treat

  18. Respiratory syncytial virus infections enhance cigarette smoke induced COPD in mice.

    Directory of Open Access Journals (Sweden)

    Robert F Foronjy

    Full Text Available Respiratory syncytial viral (RSV infections are a frequent cause of chronic obstructive pulmonary disease (COPD exacerbations, which are a major factor in disease progression and mortality. RSV is able to evade antiviral defenses to persist in the lungs of COPD patients. Though RSV infection has been identified in COPD, its contribution to cigarette smoke-induced airway inflammation and lung tissue destruction has not been established. Here we examine the long-term effects of cigarette smoke exposure, in combination with monthly RSV infections, on pulmonary inflammation, protease production and remodeling in mice. RSV exposures enhanced the influx of macrophages, neutrophils and lymphocytes to the airways of cigarette smoke exposed C57BL/6J mice. This infiltration of cells was most pronounced around the vasculature and bronchial airways. By itself, RSV caused significant airspace enlargement and fibrosis in mice and these effects were accentuated with concomitant smoke exposure. Combined stimulation with both smoke and RSV synergistically induced cytokine (IL-1α, IL-17, IFN-γ, KC, IL-13, CXCL9, RANTES, MIF and GM-CSF and protease (MMP-2, -8, -12, -13, -16 and cathepsins E, S, W and Z expression. In addition, RSV exposure caused marked apoptosis within the airways of infected mice, which was augmented by cigarette smoke exposure. RSV and smoke exposure also reduced protein phosphatase 2A (PP2A and protein tyrosine phosphates (PTP1B expression and activity. This is significant as these phosphatases counter smoke-induced inflammation and protease expression. Together, these findings show for the first time that recurrent RSV infection markedly enhances inflammation, apoptosis and tissue destruction in smoke-exposed mice. Indeed, these results indicate that preventing RSV transmission and infection has the potential to significantly impact on COPD severity and progression.

  19. Neonatal herpes simplex virus infections.

    Science.gov (United States)

    Pinninti, Swetha G; Kimberlin, David W

    2018-04-01

    Neonatal herpes simplex virus (HSV) is an uncommon but devastating infection in the newborn, associated with significant morbidity and mortality. The use of PCR for identification of infected infants and acyclovir for treatment has significantly improved the prognosis for affected infants. The subsequent use of suppressive therapy with oral acyclovir following completion of parenteral treatment of acute disease has further enhanced the long-term prognosis for these infants. This review article will discuss the epidemiology, risk factors and routes of acquisition, clinical presentation, and evaluation of an infant suspected to have the infection, and treatment of proven neonatal HSV disease. Copyright © 2018 Elsevier Inc. All rights reserved.

  20. Israeli Acute Paralysis Virus Infection Leads to an Enhanced RNA Interference Response and Not Its Suppression in the Bumblebee Bombus terrestris

    Directory of Open Access Journals (Sweden)

    Kaat Cappelle

    2016-12-01

    Full Text Available RNA interference (RNAi is the primary antiviral defense system in insects and its importance for pollinator health is indisputable. In this work, we examined the effect of Israeli acute paralysis virus (IAPV infection on the RNAi process in the bumblebee, Bombus terrestris, and whether the presence of possible functional viral suppressors could alter the potency of the host’s immune response. For this, a two-fold approach was used. Through a functional RNAi assay, we observed an enhancement of the RNAi system after IAPV infection instead of its suppression, despite only minimal upregulation of the genes involved in RNAi. Besides, the presence of the proposed suppressor 1A and the predicted OrfX protein in IAPV could not be confirmed using high definition mass spectrometry. In parallel, when bumblebees were infected with cricket paralysis virus (CrPV, known to encode a suppressor of RNAi, no increase in RNAi efficiency was seen. For both viruses, pre-infection with the one virus lead to a decreased replication of the other virus, indicating a major effect of competition. These results are compelling in the context of Dicistroviridae in multi-virus/multi-host networks as the effect of a viral infection on the RNAi machinery may influence subsequent virus infections.

  1. [Nosocomial virus infections].

    Science.gov (United States)

    Eggers, H J

    1986-12-01

    Enveloped viruses, e.g. influenza- or varicella viruses may cause highly contagious airborne infections. Their spread is difficult to control, also in hospitals. In the case of influenza and varicella immune prophylaxis and chemotherapy/chemoprophylaxis are possible. This is of particular significance, since varicella and zoster are of increasing importance for immunocompromized patients. Diarrhea is caused to a large extent by viruses. Rotavirus infections play an important role in infancy, and are frequently acquired in the hospital. In a study on infectious gastroenteritis of infants in a hospital we were able to show that 30 percent of all rotavirus infections were of nosocomial origin. Admission of a rotavirus-excreting patient (or personnel) may start a long chain of rotavirus infections on pediatric wards. Even careful hygienic measures in the hospital can hardly prevent the spread of enterovirus infections. Such infections may be severe and lethal for newborns, as shown by us in a study on an outbreak of echovirus 11 disease on a maternity ward. We have recently obtained data on the "stickiness" of enteroviruses on human skin. This could explain essential features of the spread of enteroviruses in the population.

  2. Upon Infection the Cellular WD Repeat-containing Protein 5 (WDR5) Localizes to Cytoplasmic Inclusion Bodies and Enhances Measles Virus Replication.

    Science.gov (United States)

    Ma, Dzwokai; George, Cyril X; Nomburg, Jason; Pfaller, Christian K; Cattaneo, Roberto; Samuel, Charles E

    2017-12-13

    Replication of negative-strand RNA viruses occurs in association with discrete cytoplasmic foci called inclusion bodies. Whereas inclusion bodies represent a prominent subcellular structure induced by viral infection, our knowledge of the cellular protein components involved in inclusion body formation and function is limited. Using measles virus-infected HeLa cells, we found that the WD repeat-containing protein 5 (WDR5), a subunit of histone H3 lysine 4 methyltransferases, was selectively recruited to virus-induced inclusion bodies. Furthermore, WDR5 was found in complexes containing viral proteins associated with RNA replication. WDR5 was not detected with mitochondria, stress granules, or other known secretory or endocytic compartments of infected cells. WDR5 deficiency decreased both viral protein production and infectious virus yields. Interferon production was modestly increased in WDR5 deficient cells. Thus, our study identifies WDR5 as a novel viral inclusion body-associated cellular protein and suggests a role for WDR5 in promoting viral replication. IMPORTANCE Measles virus is a human pathogen that remains a global concern with more than 100,000 measles-related deaths annually despite the availability of an effective vaccine. As measles continues to cause significant morbidity and mortality, understanding the virus-host interactions at the molecular level that affect virus replication efficiency is important for development and optimization of treatment procedures. Measles virus is an RNA virus that encodes six genes and replicates in the cytoplasm of infected cells in discrete cytoplasmic replication bodies, though little is known of the biochemical nature of these structures. Here we show that the cellular protein WDR5 is enriched in the cytoplasmic viral replication factories and enhances virus growth. WDR5-containing protein complex includes viral proteins responsible for viral RNA replication. Thus, we have identified WDR5 as a host factor that

  3. [Zika virus infection during pregnancy].

    Science.gov (United States)

    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. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  4. Fcγ-receptor IIa-mediated Src Signaling Pathway Is Essential for the Antibody-Dependent Enhancement of Ebola Virus Infection.

    Directory of Open Access Journals (Sweden)

    Wakako Furuyama

    2016-12-01

    Full Text Available Antibody-dependent enhancement (ADE of Ebola virus (EBOV infection has been demonstrated in vitro, raising concerns about the detrimental potential of some anti-EBOV antibodies. ADE has been described for many viruses and mostly depends on the cross-linking of virus-antibody complexes to cell surface Fc receptors, leading to enhanced infection. However, little is known about the molecular mechanisms underlying this phenomenon. Here we show that Fcγ-receptor IIa (FcγRIIa-mediated intracellular signaling through Src family protein tyrosine kinases (PTKs is required for ADE of EBOV infection. We found that deletion of the FcγRIIa cytoplasmic tail abolished EBOV ADE due to decreased virus uptake into cellular endosomes. Furthermore, EBOV ADE, but not non-ADE infection, was significantly reduced by inhibition of the Src family protein PTK pathway, which was also found to be important to promote phagocytosis/macropinocytosis for viral uptake into endosomes. We further confirmed a significant increase of the Src phosphorylation mediated by ADE. These data suggest that antibody-EBOV complexes bound to the cell surface FcγRIIa activate the Src signaling pathway that leads to enhanced viral entry into cells, providing a novel perspective for the general understanding of ADE of virus infection.

  5. Medroxyprogesterone acetate and levonorgestrel increase genital mucosal permeability and enhance susceptibility to genital herpes simplex virus type 2 infection.

    Science.gov (United States)

    Quispe Calla, N E; Vicetti Miguel, R D; Boyaka, P N; Hall-Stoodley, L; Kaur, B; Trout, W; Pavelko, S D; Cherpes, T L

    2016-11-01

    Depot-medroxyprogesterone acetate (DMPA) is a hormonal contraceptive especially popular in areas with high prevalence of HIV and other sexually transmitted infections (STI). Although observational studies identify DMPA as an important STI risk factor, mechanisms underlying this connection are undefined. Levonorgestrel (LNG) is another progestin used for hormonal contraception, but its effect on STI susceptibility is much less explored. Using a mouse model of genital herpes simplex virus type 2 (HSV-2) infection, we herein found that DMPA and LNG similarly reduced genital expression of the desmosomal cadherin desmoglein-1α (DSG1α), enhanced access of inflammatory cells to genital tissue by increasing mucosal epithelial permeability, and increased susceptibility to viral infection. Additional studies with uninfected mice revealed that DMPA-mediated increases in mucosal permeability promoted tissue inflammation by facilitating endogenous vaginal microbiota invasion. Conversely, concomitant treatment of mice with DMPA and intravaginal estrogen restored mucosal barrier function and prevented HSV-2 infection. Evaluating ectocervical biopsy tissue from women before and 1 month after initiating DMPA remarkably revealed that inflammation and barrier protection were altered by treatment identically to changes seen in progestin-treated mice. Together, our work reveals DMPA and LNG diminish the genital mucosal barrier; a first-line defense against all STI, but may offer foundation for new contraceptive strategies less compromising of barrier protection.

  6. Enhancement of feline immunodeficiency virus infection after immunization with envelope glycoprotein subunit vaccines.

    NARCIS (Netherlands)

    C.H.J. Siebelink (Kees); E.J. Tijhaar (Edwin); R.C. Huisman (Robin); W. Huisman (Willem); A. de Ronde; I.H. Darby; M.J. Francis; G.F. Rimmelzwaan (Guus); A.D.M.E. Osterhaus (Albert)

    1995-01-01

    textabstractCats were immunized three times with different recombinant feline immunodeficiency virus (FIV) candidate vaccines. Recombinant vaccinia virus (rVV)-expressed envelope glycoprotein with (vGR657) or without (vGR657 x 15) the cleavage site and an FIV envelope bacterial fusion protein

  7. Evaluation of synthetic infection-enhancing lipopeptides as adjuvants for a live-attenuated canine distemper virus vaccine administered intra-nasally to ferrets.

    Science.gov (United States)

    Nguyen, D Tien; Ludlow, Martin; van Amerongen, Geert; de Vries, Rory D; Yüksel, Selma; Verburgh, R Joyce; Osterhaus, Albert D M E; Duprex, W Paul; de Swart, Rik L

    2012-07-20

    Inactivated paramyxovirus vaccines have been associated with hypersensitivity responses upon challenge infection. For measles and canine distemper virus (CDV) safe and effective live-attenuated virus vaccines are available, but for human respiratory syncytial virus and human metapneumovirus development of such vaccines has proven difficult. We recently identified three synthetic bacterial lipopeptides that enhance paramyxovirus infections in vitro, and hypothesized these could be used as adjuvants to promote immune responses induced by live-attenuated paramyxovirus vaccines. Here, we tested this hypothesis using a CDV vaccination and challenge model in ferrets. Three groups of six animals were intra-nasally vaccinated with recombinant (r) CDV(5804P)L(CCEGFPC) in the presence or absence of the infection-enhancing lipopeptides Pam3CSK4 or PHCSK4. The recombinant CDV vaccine virus had previously been described to be over-attenuated in ferrets. A group of six animals was mock-vaccinated as control. Six weeks after vaccination all animals were challenged with a lethal dose of rCDV strain Snyder-Hill expressing the red fluorescent protein dTomato. Unexpectedly, intra-nasal vaccination of ferrets with rCDV(5804P)L(CCEGFPC) in the absence of lipopeptides resulted in good immune responses and protection against lethal challenge infection. However, in animals vaccinated with lipopeptide-adjuvanted virus significantly higher vaccine virus loads were detected in nasopharyngeal lavages and peripheral blood mononuclear cells. In addition, these animals developed significantly higher CDV neutralizing antibody titers compared to animals vaccinated with non-adjuvanted vaccine. This study demonstrates that the synthetic cationic lipopeptides Pam3CSK4 and PHCSK4 not only enhance paramyxovirus infection in vitro, but also in vivo. Given the observed enhancement of immunogenicity their potential as adjuvants for other live-attenuated paramyxovirus vaccines should be considered

  8. Enhanced lysis of herpes simplex virus type 1-infected mouse cell lines by NC and NK effectors

    Energy Technology Data Exchange (ETDEWEB)

    Colmenares, C.; Lopez, C.

    1986-05-01

    Spontaneously cytotoxic murine lymphocytes lysed certain cell types infected by herpes simplex virus type 1 (HSV-1) better than uninfected cells. Although HSV-1 adsorbed to the surface of all the target cells, those in which the virus replicated more efficiently were lysed to a greater extent. As targets, the authors used cell lines that, when uninfected, were spontaneously lysed by NK cells (YAC-1) or by NC cells (WEHI-164). They also used a fibroblastoid cell line (M50) and a monocytic tumor line (PU51R), which were not spontaneously killed. NK cells lysed HSV-1-infected YAC cells better than uninfected cells, and an NC-like activity selectively lysed HSV-1-infected WEHI cells. These findings were consistent with the results of experiments performed to define the role of interferon in induction of virus-augmented cytolysis. Increased lysis of YAC-HSV and PU51R-HSV was entirely due to interferon activation and was completely abolished by performing the /sup 51/Cr-release assay in the presence of anti-interferon serum. The data show that HSV-1 infection of NK/NC targets induces increased cytotoxity, but the effector cell responsible for lysis is determined by the uninfected target, or by an interaction between the virus and target cell, rather than by a viral determinant alone.

  9. Enhanced resistance to herpes simplex virus type 1 infection in transgenic mice expressing a soluble form of herpesvirus entry mediator

    International Nuclear Information System (INIS)

    Ono, Etsuro; Yoshino, Saori; Amagai, Keiko; Taharaguchi, Satoshi; Kimura, Chiemi; Morimoto, Junko; Inobe, Manabu; Uenishi, Tomoko; Uede, Toshimitsu

    2004-01-01

    Herpesvirus entry mediator (HVEM) is a member of the tumor necrosis factor (TNF) receptor family used as a cellular receptor by virion glycoprotein D (gD) of herpes simplex virus (HSV). Both human and mouse forms of HVEM can mediate entry of HSV-1 but have no entry activity for pseudorabies virus (PRV). To assess the antiviral potential of HVEM in vivo, three transgenic mouse lines expressing a soluble form of HVEM (HVEMIg) consisting of an extracellular domain of murine HVEM and the Fc portion of human IgG1 were generated. All of the transgenic mouse lines showed marked resistance to HSV-1 infection when the mice were challenged intraperitoneally with HSV-1, but not to PRV infection. The present results demonstrate that HVEMIg is able to exert a significant antiviral effect against HSV-1 infection in vivo

  10. Susceptibility to viral infection is enhanced by stable expression of 3A or 3AB proteins from foot-and-mouth disease virus

    International Nuclear Information System (INIS)

    Rosas, Maria F.; Vieira, Yuri A.; Postigo, Raul; Martin-Acebes, Miguel A.; Armas-Portela, Rosario; Martinez-Salas, Encarnacion; Sobrino, Francisco

    2008-01-01

    The foot-and-mouth disease virus (FMDV) 3A protein is involved in virulence and host range. A distinguishing feature of FMDV 3B among picornaviruses is that three non-identical copies are encoded in the viral RNA and required for optimal replication in cell culture. Here, we have studied the involvement of the 3AB region on viral infection using constitutive and transient expression systems. BHK-21 stably transformed clones expressed low levels of FMDV 3A or 3A(B) proteins in the cell cytoplasm. Transformed cells stably expressing these proteins did not exhibit inner cellular rearrangements detectable by electron microscope analysis. Upon FMDV infection, clones expressing either 3A alone or 3A(B) proteins showed a significant increase in the percentage of infected cells, the number of plaque forming units and the virus yield. The 3A-enhancing effect was specific for FMDV as no increase in viral multiplication was observed in transformed clones infected with another picornavirus, encephalomyocarditis virus, or the negative-strand RNA virus vesicular stomatitis virus. A potential role of 3A protein in viral RNA translation was discarded by the lack of effect on FMDV IRES-dependent translation. Increased viral susceptibility was not caused by a released factor; neither the supernatant of transformed clones nor the addition of purified 3A protein to the infection medium was responsible for this effect. Unlike stable expression, high levels of 3A or 3A(B) protein transient expression led to unspecific inhibition of viral infection. Therefore, the effect observed on viral yield, which inversely correlated with the intracellular levels of 3A protein, suggests a transacting role operating on the FMDV multiplication cycle

  11. Regulation of tumour related genes by dynamic epigenetic alteration at enhancer regions in gastric epithelial cells infected by Epstein-Barr virus.

    Science.gov (United States)

    Okabe, Atsushi; Funata, Sayaka; Matsusaka, Keisuke; Namba, Hiroe; Fukuyo, Masaki; Rahmutulla, Bahityar; Oshima, Motohiko; Iwama, Atsushi; Fukayama, Masashi; Kaneda, Atsushi

    2017-08-11

    Epstein-Barr virus (EBV) infection is associated with tumours such as Burkitt lymphoma, nasopharyngeal carcinoma, and gastric cancer. We previously showed that EBV(+) gastric cancer presents an extremely high-methylation epigenotype and this aberrant DNA methylation causes silencing of multiple tumour suppressor genes. However, the mechanisms that drive EBV infection-mediated tumorigenesis, including other epigenomic alteration, remain unclear. We analysed epigenetic alterations induced by EBV infection especially at enhancer regions, to elucidate their contribution to tumorigenesis. We performed ChIP sequencing on H3K4me3, H3K4me1, H3K27ac, H3K27me3, and H3K9me3 in gastric epithelial cells infected or not with EBV. We showed that repressive marks were redistributed after EBV infection, resulting in aberrant enhancer activation and repression. Enhancer dysfunction led to the activation of pathways related to cancer hallmarks (e.g., resisting cell death, disrupting cellular energetics, inducing invasion, evading growth suppressors, sustaining proliferative signalling, angiogenesis, and tumour-promoting inflammation) and inactivation of tumour suppressive pathways. Deregulation of cancer-related genes in EBV-infected gastric epithelial cells was also observed in clinical EBV(+) gastric cancer specimens. Our analysis showed that epigenetic alteration associated with EBV-infection may contribute to tumorigenesis through enhancer activation and repression.

  12. Enhancing virus-specific immunity in vivo by combining therapeutic vaccination and PD-L1 blockade in chronic hepadnaviral infection.

    Directory of Open Access Journals (Sweden)

    Jia Liu

    2014-01-01

    Full Text Available Hepatitis B virus (HBV persistence is facilitated by exhaustion of CD8 T cells that express the inhibitory receptor programmed cell death-1 (PD-1. Improvement of the HBV-specific T cell function has been obtained in vitro by inhibiting the PD-1/PD-ligand 1 (PD-L1 interaction. In this study, we examined whether in vivo blockade of the PD-1 pathway enhances virus-specific T cell immunity and leads to the resolution of chronic hepadnaviral infection in the woodchuck model. The woodchuck PD-1 was first cloned, characterized, and its expression patterns on T cells from woodchucks with acute or chronic woodchuck hepatitis virus (WHV infection were investigated. Woodchucks chronically infected with WHV received a combination therapy with nucleoside analogue entecavir (ETV, therapeutic DNA vaccination and woodchuck PD-L1 antibody treatment. The gain of T cell function and the suppression of WHV replication by this therapy were evaluated. We could show that PD-1 expression on CD8 T cells was correlated with WHV viral loads during WHV infection. ETV treatment significantly decreased PD-1 expression on CD8 T cells in chronic carriers. In vivo blockade of PD-1/PD-L1 pathway on CD8 T cells, in combination with ETV treatment and DNA vaccination, potently enhanced the function of virus-specific T cells. Moreover, the combination therapy potently suppressed WHV replication, leading to sustained immunological control of viral infection, anti-WHs antibody development and complete viral clearance in some woodchucks. Our results provide a new approach to improve T cell function in chronic hepatitis B infection, which may be used to design new immunotherapeutic strategies in patients.

  13. Persistent Transmissible Gastroenteritis Virus Infection Enhances Enterotoxigenic Escherichia coli K88 Adhesion by Promoting Epithelial-Mesenchymal Transition in Intestinal Epithelial Cells.

    Science.gov (United States)

    Xia, Lu; Dai, Lei; Yu, Qinghua; Yang, Qian

    2017-11-01

    Transmissible gastroenteritis virus (TGEV) is a coronavirus characterized by diarrhea and high morbidity rates, and the mortality rate is 100% in piglets less than 2 weeks old. Pigs infected with TGEV often suffer secondary infection by other pathogens, which aggravates the severity of diarrhea, but the mechanisms remain unknown. Here, we hypothesized that persistent TGEV infection stimulates the epithelial-mesenchymal transition (EMT), and thus enterotoxigenic Escherichia coli (ETEC) can more easily adhere to generating cells. Intestinal epithelial cells are the primary targets of TGEV and ETEC infections. We found that TGEV can persistently infect porcine intestinal columnar epithelial cells (IPEC-J2) and cause EMT, consistent with multiple changes in key cell characteristics. Infected cells display fibroblast-like shapes; exhibit increases in levels of mesenchymal markers with a corresponding loss of epithelial markers; have enhanced expression levels of interleukin-1β (IL-1β), IL-6, IL-8, transforming growth factor β (TGF-β), and tumor necrosis factor alpha (TNF-α) mRNAs; and demonstrate increases in migratory and invasive behaviors. Additional experiments showed that the activation of the phosphatidylinositol 3-kinase (PI3K)/Akt and extracellular signal-regulated kinase (ERK) signaling pathways via TGF-β is critical for the TGEV-mediated EMT process. Cellular uptake is also modified in cells that have undergone EMT. TGEV-infected cells have higher levels of integrin α5 and fibronectin and exhibit enhanced ETEC K88 adhesion. Reversal of EMT reduces ETEC K88 adhesion and inhibits the expression of integrin α5 and fibronectin. Overall, these results suggest that TGEV infection induces EMT in IPEC-J2 cells, increasing the adhesion of ETEC K88 in the intestine and facilitating dual infection. IMPORTANCE Transmissible gastroenteritis virus (TGEV) causes pig diarrhea and is often followed by secondary infection by other pathogens. In this study, we showed

  14. O-GlcNAc modification of the coat protein of the potyvirus Plum pox virus enhances viral infection.

    Science.gov (United States)

    Pérez, José de Jesús; Udeshi, Namrata D; Shabanowitz, Jeffrey; Ciordia, Sergio; Juárez, Silvia; Scott, Cheryl L; Olszewski, Neil E; Hunt, Donald F; García, Juan Antonio

    2013-08-01

    O-GlcNAcylation is a dynamic protein modification which has been studied mainly in metazoans. We reported previously that an Arabidopsis thaliana O-GlcNAc transferase modifies at least two threonine residues of the Plum pox virus (PPV) capsid protein (CP). Now, six additional residues were shown to be involved in O-GlcNAc modification of PPV CP. CP O-GlcNAcylation was abolished in the PPV CP7-T/A mutant, in which seven threonines were mutated. PPV CP7-T/A infected Nicotiana clevelandii, Nicotiana benthamiana, and Prunus persica without noticeable defects. However, defects in infection of A. thaliana were readily apparent. In mixed infections of wild-type arabidopsis, the CP7-T/A mutant was outcompeted by wild-type virus. These results indicate that CP O-GlcNAcylation has a major role in the infection process. O-GlcNAc modification may have a role in virion assembly and/or stability as the CP of PPV CP7-T/A was more sensitive to protease digestion than that of the wild-type virus. Copyright © 2013 Elsevier Inc. All rights reserved.

  15. Human immunodeficiency virus infection and the liver.

    Science.gov (United States)

    Crane, Megan; Iser, David; Lewin, Sharon R

    2012-03-27

    Liver disease in human immunodeficiency virus (HIV)-infected individuals encompasses the spectrum from abnormal liver function tests, liver decompensation, with and without evidence of cirrhosis on biopsy, to non-alcoholic liver disease and its more severe form, non-alcoholic steatohepatitis and hepatocellular cancer. HIV can infect multiple cells in the liver, leading to enhanced intrahepatic apoptosis, activation and fibrosis. HIV can also alter gastro-intestinal tract permeability, leading to increased levels of circulating lipopolysaccharide that may have an impact on liver function. This review focuses on recent changes in the epidemiology, pathogenesis and clinical presentation of liver disease in HIV-infected patients, in the absence of co-infection with hepatitis B virus or hepatitis C virus, with a specific focus on issues relevant to low and middle income countries.

  16. Enhancing the sensitivity of Dengue virus serotype detection by RT-PCR among infected children in India.

    Science.gov (United States)

    Ahamed, Syed Fazil; Vivek, Rosario; Kotabagi, Shalini; Nayak, Kaustuv; Chandele, Anmol; Kaja, Murali-Krishna; Shet, Anita

    2017-06-01

    Dengue surveillance relies on reverse transcription-polymerase chain reaction (RT-PCR), for confirmation of dengue virus (DENV) serotypes. We compared efficacies of published and modified primer sets targeting envelope (Env) and capsid-premembrane (C-prM) genes for detection of circulating DENV serotypes in southern India. Acute samples from children with clinically-diagnosed dengue were used for RT-PCR testing. All samples were also subjected to dengue serology (NS1 antigen and anti-dengue-IgM/IgG rapid immunochromatographic assay). Nested RT-PCR was performed on viral RNA using three methods targeting 654bp C-prM, 511bp C-prM and 641bp Env regions, respectively. RT-PCR-positive samples were validated by population sequencing. Among 171 children with suspected dengue, 121 were dengue serology-positive and 50 were dengue serology-negative. Among 121 serology-positives, RT-PCR detected 91 (75.2%) by CprM654, 72 (59.5%) by CprM511, and 74 (61.1%) by Env641. Among 50 serology-negatives, 10 (20.0%) were detected by CprM654, 12 (24.0%) by CprM511, and 11 (22.0%) by Env641. Overall detection rate using three methods sequentially was 82.6% (100/121) among serology-positive and 40.0% (20/50) among serology-negative samples; 6.6% (8/120) had co-infection with multiple DENV serotypes. We conclude that detection of acute dengue was enhanced by a modified RT-PCR method targeting the 654bp C-prM region, and further improved by using all three methods sequentially. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. ICAM-1-based rabies virus vaccine shows increased infection and activation of primary murine B cells in vitro and enhanced antibody titers in-vivo.

    Directory of Open Access Journals (Sweden)

    James E Norton

    Full Text Available We have previously shown that live-attenuated rabies virus (RABV-based vaccines infect and directly activate murine and human primary B cells in-vitro, which we propose can be exploited to help develop a single-dose RABV-based vaccine. Here we report on a novel approach to utilize the binding of Intracellular Adhesion Molecule-1 (ICAM-1 to its binding partner, Lymphocyte Function-associated Antigen-1 (LFA-1, on B cells to enhance B cell activation and RABV-specific antibody responses. We used a reverse genetics approach to clone, recover, and characterize a live-attenuated recombinant RABV-based vaccine expressing the murine Icam1 gene (rRABV-mICAM-1. We show that the murine ICAM-1 gene product is incorporated into virus particles, potentially exposing ICAM-1 to extracellular binding partners. While rRABV-mICAM-1 showed 10-100-fold decrease in viral titers on baby hamster kidney cells compared to the parental virus (rRABV, rRABV-mICAM-1 infected and activated primary murine B cells in-vitro more efficiently than rRABV, as indicated by significant upregulation of CD69, CD40, and MHCII on the surface of infected B cells. ICAM-1 expression on the virus surface was responsible for enhanced B cell infection since pre-treating rRABV-mICAM-1 with a neutralizing anti-ICAM-1 antibody reduced B cell infection to levels observed with rRABV alone. Furthermore, 100-fold less rRABV-mICAM-1 was needed to induce antibody titers in immunized mice equivalent to antibody titers observed in rRABV-immunized mice. Of note, only 10(3 focus forming units (ffu/mouse of rRABV-mICAM-1 was needed to induce significant anti-RABV antibody titers as early as five days post-immunization. As both speed and potency of antibody responses are important in controlling human RABV infection in a post-exposure setting, these data show that expression of Icam1 from the RABV genome, which is then incorporated into the virus particle, is a promising strategy for the development of a

  18. Autophagic machinery activated by dengue virus enhances virus replication

    International Nuclear Information System (INIS)

    Lee, Y.-R.; Lei, H.-Y.; Liu, M.-T.; Wang, J.-R.; Chen, S.-H.; Jiang-Shieh, Y.-F.; Lin, Y.-S.; Yeh, T.-M.; Liu, C.-C.; Liu, H.-S.

    2008-01-01

    Autophagy is a cellular response against stresses which include the infection of viruses and bacteria. We unravel that Dengue virus-2 (DV2) can trigger autophagic process in various infected cell lines demonstrated by GFP-LC3 dot formation and increased LC3-II formation. Autophagosome formation was also observed under the transmission electron microscope. DV2-induced autophagy further enhances the titers of extracellular and intracellular viruses indicating that autophagy can promote viral replication in the infected cells. Moreover, our data show that ATG5 protein is required to execute DV2-induced autophagy. All together, we are the first to demonstrate that DV can activate autophagic machinery that is favorable for viral replication

  19. Protective Effect of Panax notoginseng Root Water Extract against Influenza A Virus Infection by Enhancing Antiviral Interferon-Mediated Immune Responses and Natural Killer Cell Activity

    Directory of Open Access Journals (Sweden)

    Jang-Gi Choi

    2017-11-01

    Full Text Available Influenza is an acute respiratory illness caused by the influenza A virus, which causes economic losses and social disruption mainly by increasing hospitalization and mortality rates among the elderly and people with chronic diseases. Influenza vaccines are the most effective means of preventing seasonal influenza, but can be completely ineffective if there is an antigenic mismatch between the seasonal vaccine virus and the virus circulating in the community. In addition, influenza viruses resistant to antiviral drugs are emerging worldwide. Thus, there is an urgent need to develop new vaccines and antiviral drugs against these viruses. In this study, we conducted in vitro and in vivo analyses of the antiviral effect of Panax notoginseng root (PNR, which is used as an herbal medicine and nutritional supplement in Korea and China. We confirmed that PNR significantly prevented influenza virus infection in a concentration-dependent manner in mouse macrophages. In addition, PNR pretreatment inhibited viral protein (PB1, PB2, HA, NA, M1, PA, M2, and NP and viral mRNA (NS1, HA, PB2, PA, NP, M1, and M2 expression. PNR pretreatment also increased the secretion of pro-inflammatory cytokines [tumor necrosis factor alpha and interleukin 6] and interferon (IFN-beta and the phosphorylation of type-I IFN-related proteins (TANK-binding kinase 1, STAT1, and IRF3 in vitro. In mice exposed to the influenza A H1N1 virus, PNR treatment decreased mortality by 90% and prevented weight loss (by approximately 10% compared with the findings in untreated animals. In addition, splenocytes from PNR-administered mice displayed significantly enhanced natural killer (NK cell activity against YAC-1 cells. Taking these findings together, PNR stimulates an antiviral response in murine macrophages and mice that protects against viral infection, which may be attributable to its ability to stimulate NK cell activity. Further investigations are needed to reveal the molecular

  20. Recombinant Vaccinia Viruses Coding Transgenes of Apoptosis-Inducing Proteins Enhance Apoptosis But Not Immunogenicity of Infected Tumor Cells

    Science.gov (United States)

    Tkachenko, Anastasiya; Richter, Vladimir

    2017-01-01

    Genetic modifications of the oncolytic vaccinia virus (VV) improve selective tumor cell infection and death, as well as activation of antitumor immunity. We have engineered a double recombinant VV, coding human GM-CSF, and apoptosis-inducing protein apoptin (VV-GMCSF-Apo) for comparing with the earlier constructed double recombinant VV-GMCSF-Lact, coding another apoptosis-inducing protein, lactaptin, which activated different cell death pathways than apoptin. We showed that both these recombinant VVs more considerably activated a set of critical apoptosis markers in infected cells than the recombinant VV coding GM-CSF alone (VV-GMCSF-dGF): these were phosphatidylserine externalization, caspase-3 and caspase-7 activation, DNA fragmentation, and upregulation of proapoptotic protein BAX. However, only VV-GMCSF-Lact efficiently decreased the mitochondrial membrane potential of infected cancer cells. Investigating immunogenic cell death markers in cancer cells infected with recombinant VVs, we demonstrated that all tested recombinant VVs were efficient in calreticulin and HSP70 externalization, decrease of cellular HMGB1, and ATP secretion. The comparison of antitumor activity against advanced MDA-MB-231 tumor revealed that both recombinants VV-GMCSF-Lact and VV-GMCSF-Apo efficiently delay tumor growth. Our results demonstrate that the composition of GM-CSF and apoptosis-inducing proteins in the VV genome is very efficient tool for specific killing of cancer cells and for activation of antitumor immunity. PMID:28951871

  1. Rice Dwarf Virus P2 Protein Hijacks Auxin Signaling by Directly Targeting the Rice OsIAA10 Protein, Enhancing Viral Infection and Disease Development.

    Directory of Open Access Journals (Sweden)

    Lian Jin

    2016-09-01

    Full Text Available The phytohormone auxin plays critical roles in regulating myriads of plant growth and developmental processes. Microbe infection can disturb auxin signaling resulting in defects in these processes, but the underlying mechanisms are poorly understood. Auxin signaling begins with perception of auxin by a transient co-receptor complex consisting of an F-box transport inhibitor response 1/auxin signaling F-box (TIR1/AFB protein and an auxin/indole-3-acetic acid (Aux/IAA protein. Auxin binding to the co-receptor triggers ubiquitination and 26S proteasome degradation of the Aux/IAA proteins, leading to subsequent events, including expression of auxin-responsive genes. Here we report that Rice dwarf virus (RDV, a devastating pathogen of rice, causes disease symptoms including dwarfing, increased tiller number and short crown roots in infected rice as a result of reduced sensitivity to auxin signaling. The RDV capsid protein P2 binds OsIAA10, blocking the interaction between OsIAA10 and OsTIR1 and inhibiting 26S proteasome-mediated OsIAA10 degradation. Transgenic rice plants overexpressing wild-type or a dominant-negative (degradation-resistant mutant of OsIAA10 phenocopy RDV symptoms are more susceptible to RDV infection; however, knockdown of OsIAA10 enhances the resistance of rice to RDV infection. Our findings reveal a previously unknown mechanism of viral protein reprogramming of a key step in auxin signaling initiation that enhances viral infection and pathogenesis.

  2. Heat shock and herpes virus: enhanced reactivation without untargeted mutagenesis

    International Nuclear Information System (INIS)

    Lytle, C.D.; Carney, P.G.

    1988-01-01

    Enhanced reactivation of Ultraviolet-irradiated virus has been reported to occur in heat-shocked host cells. Since enhanced virus reactivation is often accompanied by untargeted mutagenesis, we investigated whether such mutagenesis would occur for herpes simplex virus (HSV) in CV-1 monkey kidney cells subjected to heat shock. In addition to expressing enhanced reactivation, the treated cells were transiently more susceptible to infection by unirradiated HSV. No mutagenesis of unirradiated HSV was found whether infection occurred at the time of increased susceptibility to infection or during expression of enhanced viral reactivation

  3. Radiation enhanced reactivation of nuclear replicating mammalian viruses

    International Nuclear Information System (INIS)

    Bockstahler, L.E.; Lytle, C.D.

    1977-01-01

    When CV-1 monkey kidney cells were UV-irradiated (0 to 18 J/m 2 ) or X-irradiated (0 to 10 krads) before infection with UV-irradiated simian adenovirus 7 (SA7) or simian virus 40 (SV40), increases in the infectivity of these nuclear replicating viruses as measured by plaque formation were observed. These radiation enhanced reactivations, UV enhanced reactivation (UVER) and X-ray enhanced reactivation (X-ray ER), occurred both when virus infection immediately followed irradiation of the cells (except for X-ray ER with SA7) and when virus infection was delayed until 3 to 5 days after cell irradiation. While there was little difference in the levels of reactivation of UV-irradiated SV40 between immediate and delayed infection, delayed infection resulted in higher levels of reactivation of SA7. X-ray enhanced reactivation of UV-irradiated Herpes simplex virus persisted for several days but did not increase. Thus, X-ray enhanced and UV enhanced reactivations of these mammalian viruses were relatively long-lived effects. Essentially no UVER or X-ray ER was found in CV-1 cells for either immediate or delayed infection with UV-irradiated vaccinia virus or poliovirus, both of which replicate in the cell cytoplasm. These results suggest UVER and X-ray ER in mammalian cells may be restricted to viruses which are replicated in the cell nucleus. (author)

  4. Oral administration of Lactobacillus plantarum strain AYA enhances IgA secretion and provides survival protection against influenza virus infection in mice.

    Directory of Open Access Journals (Sweden)

    Yosuke Kikuchi

    Full Text Available The mucosal immune system provides the first line of defense against inhaled and ingested pathogenic microbacteria and viruses. This defense system, to a large extent, is mediated by the actions of secretory IgA. In this study, we screened 140 strains of lactic acid bacteria for induction of IgA production by murine Peyer's patch cells. We selected one strain and named it Lactobacillus plantarum AYA. We found that L. plantarum AYA-induced production of IL-6 in Peyer's patch dendritic cells, with this production promoting IgA(+ B cells to differentiate into IgA-secreting plasma cells. We also observed that oral administration of L. plantarum AYA in mice caused an increase in IgA production in the small intestine and lung. This production of IgA correlated strongly with protective ability, with the treated mice surviving longer than the control mice after lethal influenza virus infection. Our data therefore reveals a novel immunoregulatory role of the L. plantarum AYA strain which enhances mucosal IgA production and provides protection against respiratory influenza virus infection.

  5. Autophagy in Measles Virus Infection

    Directory of Open Access Journals (Sweden)

    Aurore Rozières

    2017-11-01

    Full Text Available Autophagy is a biological process that helps cells to recycle obsolete cellular components and which greatly contributes to maintaining cellular integrity in response to environmental stress factors. Autophagy is also among the first lines of cellular defense against invading microorganisms, including viruses. The autophagic destruction of invading pathogens, a process referred to as xenophagy, involves cytosolic autophagy receptors, such as p62/SQSTM1 (Sequestosome 1 or NDP52/CALCOCO2 (Nuclear Dot 52 KDa Protein/Calcium Binding And Coiled-Coil Domain 2, which bind to microbial components and target them towards growing autophagosomes for degradation. However, most, if not all, infectious viruses have evolved molecular tricks to escape from xenophagy. Many viruses even use autophagy, part of the autophagy pathway or some autophagy-associated proteins, to improve their infectious potential. In this regard, the measles virus, responsible for epidemic measles, has a unique interface with autophagy as the virus can induce multiple rounds of autophagy in the course of infection. These successive waves of autophagy result from distinct molecular pathways and seem associated with anti- and/or pro-measles virus consequences. In this review, we describe what the autophagy–measles virus interplay has taught us about both the biology of the virus and the mechanistic orchestration of autophagy.

  6. DAMPs and influenza virus infection in ageing.

    Science.gov (United States)

    Samy, Ramar Perumal; Lim, Lina H K

    2015-11-01

    Influenza A virus (IAV) is a serious global health problem worldwide due to frequent and severe outbreaks. IAV causes significant morbidity and mortality in the elderly population, due to the ineffectiveness of the vaccine and the alteration of T cell immunity with ageing. The cellular and molecular link between ageing and virus infection is unclear and it is possible that damage associated molecular patterns (DAMPs) may play a role in the raised severity and susceptibility of virus infections in the elderly. DAMPs which are released from damaged cells following activation, injury or cell death can activate the immune response through the stimulation of the inflammasome through several types of receptors found on the plasma membrane, inside endosomes after endocytosis as well as in the cytosol. In this review, the detriment in the immune system during ageing and the links between influenza virus infection and ageing will be discussed. In addition, the role of DAMPs such as HMGB1 and S100/Annexin in ageing, and the enhanced morbidity and mortality to severe influenza infection in ageing will be highlighted. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Genital herpes simplex virus infections.

    Science.gov (United States)

    Rosenthal, M S

    1979-09-01

    In recent years, a great increase in interest in genital herpes has been stimulated partly by the rising prevalence of this disease and partly by observations suggesting that genital herpes is a cause of cervical cancer. The clinical pictures produced by genital herpes simplex virus infections are similar in men and women. In contrast to recurrent attacks, initial episodes of infection are generally more extensive, last longer, and are more often associated with regional lymphadenopathy and systemic symptoms. Genital herpes in pregnancy may pose a serious threat to the newborn infant. Although the data suggesting genital herpes simplex virus infection is a cause of cervical cancer are quite extensive, the evidence is largely circumstantial. In spite of these more serious aspects of genital herpes simplex virus infection, episodes of genital herpes are almost always self-limited and benign. Frequent recurrences pose the major therapeutic and management problem. At present, there is no satisfactory treatment for recurrent genital herpes simplex virus in fection. Many of the suggested therapies, although some sound very promising, are potentially dangerous and should be used only under carefully controlled conditions.

  8. Chikungunya VIrUS infection

    African Journals Online (AJOL)

    A retrospective study of 107 cases of serologically proven chikungunya (CHIK) virus infection was undertaken. All respondents 'had contracted the. 'disease at least 3 years previously; 87,9% had fully .recovered, 3,7% experienced only occasional stiff- ness or mild discomfort, 2,8% had persistent resi- dual joint stiffness but ...

  9. Neonatal Herpes Simplex Virus Infection.

    Science.gov (United States)

    James, Scott H; Kimberlin, David W

    2015-09-01

    Herpes simplex virus (HSV) 1 and HSV-2 infections are highly prevalent worldwide and are characterized by establishing lifelong infection with periods of latency interspersed with periodic episodes of reactivation. Acquisition of HSV by an infant during the peripartum or postpartum period results in neonatal HSV disease, a rare but significant infection that can be associated with severe morbidity and mortality, especially if there is dissemination or central nervous system involvement. Diagnostic and therapeutic advances have led to improvements in mortality and, to a lesser extent, neurodevelopmental outcomes, but room exists for further improvement. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. Therapeutic efficacy of antibodies lacking Fcγ receptor binding against lethal dengue virus infection is due to neutralizing potency and blocking of enhancing antibodies [corrected].

    Directory of Open Access Journals (Sweden)

    Katherine L Williams

    2013-02-01

    Full Text Available Dengue hemorrhagic fever and dengue shock syndrome (DHF/DSS are life-threatening complications following infection with one of the four serotypes of dengue virus (DENV. At present, no vaccine or antiviral therapies are available against dengue. Here, we characterized a panel of eight human or mouse-human chimeric monoclonal antibodies (MAbs and their modified variants lacking effector function and dissected the mechanism by which some protect against antibody-enhanced lethal DENV infection. We found that neutralizing modified MAbs that recognize the fusion loop or the A strand epitopes on domains II and III of the envelope protein, respectively, act therapeutically by competing with and/or displacing enhancing antibodies. By analyzing these relationships, we developed a novel in vitro suppression-of-enhancement assay that predicts the ability of modified MAbs to act therapeutically against antibody-enhanced disease in vivo. These studies provide new insight into the biology of DENV pathogenesis and the requirements for antibodies to treat lethal DENV disease.

  11. Sulfated polysaccharide, curdlan sulfate, efficiently prevents entry/fusion and restricts antibody-dependent enhancement of dengue virus infection in vitro: a possible candidate for clinical application.

    Directory of Open Access Journals (Sweden)

    Koji Ichiyama

    Full Text Available Curdlan sulfate (CRDS, a sulfated 1→3-β-D glucan, previously shown to be a potent HIV entry inhibitor, is characterized in this study as a potent inhibitor of the Dengue virus (DENV. CRDS was identified by in silico blind docking studies to exhibit binding potential to the envelope (E protein of the DENV. CRDS was shown to inhibit the DENV replication very efficiently in different cells in vitro. Minimal effective concentration of CRDS was as low as 0.1 µg/mL in LLC-MK2 cells, and toxicity was observed only at concentrations over 10 mg/mL. CRDS can also inhibit DENV-1, 3, and 4 efficiently. CRDS did not inhibit the replication of DENV subgenomic replicon. Time of addition experiments demonstrated that the compound not only inhibited viral infection at the host cell binding step, but also at an early post-attachment step of entry (membrane fusion. The direct binding of CRDS to DENV was suggested by an evident reduction in the viral titers after interaction of the virus with CRDS following an ultrafiltration device separation, as well as after virus adsorption to an alkyl CRDS-coated membrane filter. The electron microscopic features also showed that CRDS interacted directly with the viral envelope, and caused changes to the viral surface. CRDS also potently inhibited DENV infection in DC-SIGN expressing cells as well as the antibody-dependent enhancement of DENV-2 infection. Based on these data, a probable binding model of CRDS to DENV E protein was constructed by a flexible receptor and ligand docking study. The binding site of CRDS was predicted to be at the interface between domains II and III of E protein dimer, which is unique to this compound, and is apparently different from the β-OG binding site. Since CRDS has already been tested in humans without serious side effects, its clinical application can be considered.

  12. Tetraspanin Assemblies in Virus Infection

    Directory of Open Access Journals (Sweden)

    Luise Florin

    2018-05-01

    Full Text Available Tetraspanins (Tspans are a family of four-span transmembrane proteins, known as plasma membrane “master organizers.” They form Tspan-enriched microdomains (TEMs or TERMs through lateral association with one another and other membrane proteins. If multiple microdomains associate with each other, larger platforms can form. For infection, viruses interact with multiple cell surface components, including receptors, activating proteases, and signaling molecules. It appears that Tspans, such as CD151, CD82, CD81, CD63, CD9, Tspan9, and Tspan7, coordinate these associations by concentrating the interacting partners into Tspan platforms. In addition to mediating viral attachment and entry, these platforms may also be involved in intracellular trafficking of internalized viruses and assist in defining virus assembly and exit sites. In conclusion, Tspans play a role in viral infection at different stages of the virus replication cycle. The present review highlights recently published data on this topic, with a focus on events at the plasma membrane. In light of these findings, we propose a model for how Tspan interactions may organize cofactors for viral infection into distinct molecular platforms.

  13. Methamphetamine abuse affects gene expression in brain-derived microglia of SIV-infected macaques to enhance inflammation and promote virus targets

    KAUST Repository

    Najera, Julia A.

    2016-04-23

    Background Methamphetamine (Meth) abuse is a major health problem linked to the aggravation of HIV- associated complications, especially within the Central Nervous System (CNS). Within the CNS, Meth has the ability to modify the activity/function of innate immune cells and increase brain viral loads. Here, we examined changes in the gene expression profile of neuron-free microglial cell preparations isolated from the brain of macaques infected with the Simian Immunodeficiency Virus (SIV), a model of neuroAIDS, and exposed to Meth. We aimed to identify molecular patterns triggered by Meth that could explain the detection of higher brain viral loads and the development of a pro-inflammatory CNS environment in the brain of infected drug abusers. Results We found that Meth alone has a strong effect on the transcription of genes associated with immune pathways, particularly inflammation and chemotaxis. Systems analysis led to a strong correlation between Meth exposure and enhancement of molecules associated with chemokines and chemokine receptors, especially CXCR4 and CCR5, which function as co-receptors for viral entry. The increase in CCR5 expression was confirmed in the brain in correlation with increased brain viral load. Conclusions Meth enhances the availability of CCR5-expressing cells for SIV in the brain, in correlation with increased viral load. This suggests that Meth is an important factor in the susceptibility to the infection and to the aggravated CNS inflammatory pathology associated with SIV in macaques and HIV in humans.

  14. Supplementary Material for: Methamphetamine abuse affects gene expression in brain-derived microglia of SIV-infected macaques to enhance inflammation and promote virus targets

    KAUST Repository

    Najera, Julia

    2016-01-01

    Abstract Background Methamphetamine (Meth) abuse is a major health problem linked to the aggravation of HIV- associated complications, especially within the Central Nervous System (CNS). Within the CNS, Meth has the ability to modify the activity/function of innate immune cells and increase brain viral loads. Here, we examined changes in the gene expression profile of neuron-free microglial cell preparations isolated from the brain of macaques infected with the Simian Immunodeficiency Virus (SIV), a model of neuroAIDS, and exposed to Meth. We aimed to identify molecular patterns triggered by Meth that could explain the detection of higher brain viral loads and the development of a pro-inflammatory CNS environment in the brain of infected drug abusers. Results We found that Meth alone has a strong effect on the transcription of genes associated with immune pathways, particularly inflammation and chemotaxis. Systems analysis led to a strong correlation between Meth exposure and enhancement of molecules associated with chemokines and chemokine receptors, especially CXCR4 and CCR5, which function as co-receptors for viral entry. The increase in CCR5 expression was confirmed in the brain in correlation with increased brain viral load. Conclusions Meth enhances the availability of CCR5-expressing cells for SIV in the brain, in correlation with increased viral load. This suggests that Meth is an important factor in the susceptibility to the infection and to the aggravated CNS inflammatory pathology associated with SIV in macaques and HIV in humans.

  15. Virus Diseases Infecting Almond Germplasm in Lebanon

    OpenAIRE

    Adeeb Saad; Yusuf Abou-Jawdah; Zahi Kanaan-Atallah

    2000-01-01

    Cultivated and wild almond species were surveyed for virus diseases. Four viruses infected cultivated almonds (Prunus dulcis): Prunus necrotic ringspot virus (PNRSV), Prune dwarf virus (PDV), Apple chlorotic leaf spot virus (ACLSV) and Apple mosaic virus (ApMV). Only ACLSV and ApMV were detected on wild almonds, (Prunus orientalis and P. korschinskii). The occurence of PNRSV or PDV on seeds used for the production of rootstocks, on seedlings in nurseries, and on mother plants reve...

  16. Getah Virus Infection among Racehorses, Japan, 2014

    Science.gov (United States)

    Bannai, Hiroshi; Tsujimura, Koji; Kobayashi, Minoru; Kikuchi, Takuya; Yamanaka, Takashi; Kondo, Takashi

    2015-01-01

    An outbreak of Getah virus infection occurred among racehorses in Japan during September and October 2014. Of 49 febrile horses tested by reverse transcription PCR, 25 were positive for Getah virus. Viruses detected in 2014 were phylogenetically different from the virus isolated in Japan in 1978. PMID:25898181

  17. Roles for Endothelial Cells in Dengue Virus Infection

    Directory of Open Access Journals (Sweden)

    Nadine A. Dalrymple

    2012-01-01

    Full Text Available Dengue viruses cause two severe diseases that alter vascular fluid barrier functions, dengue hemorrhagic fever (DHF and dengue shock syndrome (DSS. The endothelium is the primary fluid barrier of the vasculature and ultimately the effects of dengue virus infection that cause capillary leakage impact endothelial cell (EC barrier functions. The ability of dengue virus to infect the endothelium provides a direct means for dengue to alter capillary permeability, permit virus replication, and induce responses that recruit immune cells to the endothelium. Recent studies focused on dengue virus infection of primary ECs have demonstrated that ECs are efficiently infected, rapidly produce viral progeny, and elicit immune enhancing cytokine responses that may contribute to pathogenesis. Furthermore, infected ECs have also been implicated in enhancing viremia and immunopathogenesis within murine dengue disease models. Thus dengue-infected ECs have the potential to directly contribute to immune enhancement, capillary permeability, viremia, and immune targeting of the endothelium. These effects implicate responses of the infected endothelium in dengue pathogenesis and rationalize therapeutic targeting of the endothelium and EC responses as a means of reducing the severity of dengue virus disease.

  18. Nervous System Injury and Neuroimaging of Zika Virus Infection

    Science.gov (United States)

    Wu, Shanshan; Zeng, Yu; Lerner, Alexander; Gao, Bo; Law, Meng

    2018-01-01

    In 2016, World Health Organization announced Zika virus infection and its neurological sequalae are a public health emergency of global scope. Preliminary studies have confirmed a relationship between Zika virus infection and certain neurological disorders, including microcephaly and Guillain–Barre syndrome (GBS). The neuroimaging features of microcephaly secondary to Zika virus infection include calcifications at the junction of gray–white matter and subcortical white matter with associated cortical abnormalities, diminution of white matter, large ventricles with or without hydrocephalus, cortical malformations, hypoplasia of cerebellum and brainstem, and enlargement of cerebellomedullary cistern. Contrast enhancement of the cauda equine nerve roots is the typical neuroimaging finding of GBS associated with Zika virus. This review describes the nervous system disorders and associated imaging findings seen in Zika virus infection, with the aim to improve the understanding of this disease. Imaging plays a key role on accurate diagnosis and prognostic evaluation of this disease. PMID:29740383

  19. Hepatic disorder in Zika virus infection

    Institute of Scientific and Technical Information of China (English)

    Viroj Wiwanitkit

    2016-01-01

    Zika virus infection is the present global problem. This arbovirus infection can cause acute ilness and affect fetus in utero. However, there can be other additional clinical manifestation including to the hepatic disorder. In this short commentary article, the author brielfy discusses on the liver problem due to Zika virus infection.

  20. Virus-host interaction in feline immunodeficiency virus (FIV) infection.

    Science.gov (United States)

    Taniwaki, Sueli Akemi; Figueiredo, Andreza Soriano; Araujo, João Pessoa

    2013-12-01

    Feline immunodeficiency virus (FIV) infection has been the focus of several studies because this virus exhibits genetic and pathogenic characteristics that are similar to those of the human immunodeficiency virus (HIV). FIV causes acquired immunodeficiency syndrome (AIDS) in cats, nevertheless, a large fraction of infected cats remain asymptomatic throughout life despite of persistent chronic infection. This slow disease progression may be due to the presence of factors that are involved in the natural resistance to infection and the immune response that is mounted by the animals, as well as due to the adaptation of the virus to the host. Therefore, the study of virus-host interaction is essential to the understanding of the different patterns of disease course and the virus persistence in the host, and to help with the development of effective vaccines and perhaps the cure of FIV and HIV infections. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. VSVΔG/EBOV GP-induced innate protection enhances natural killer cell activity to increase survival in a lethal mouse adapted Ebola virus infection.

    Science.gov (United States)

    Williams, Kinola J N; Qiu, Xiangguo; Fernando, Lisa; Jones, Steven M; Alimonti, Judie B

    2015-02-01

    Members of the species Zaire ebolavirus cause severe hemorrhagic fever with up to a 90% mortality rate in humans. The VSVΔG/EBOV GP vaccine has provided 100% protection in the mouse, guinea pig, and nonhuman primate (NHP) models, and has also been utilized as a post-exposure therapeutic to protect mice, guinea pigs, and NHPs from a lethal challenge of Ebola virus (EBOV). EBOV infection causes rapid mortality in human and animal models, with death occurring as early as 6 days after infection, suggesting a vital role for the innate immune system to control the infection before cells of the adaptive immune system can assume control. Natural killer (NK) cells are the predominant cell of the innate immune response, which has been shown to expand with VSVΔG/EBOV GP treatment. In the current study, an in vivo mouse model of the VSVΔG/EBOV GP post-exposure treatment was used for a mouse adapted (MA)-EBOV infection, to determine the putative VSVΔG/EBOV GP-induced protective mechanism of NK cells. NK depletion studies demonstrated that mice with NK cells survive longer in a MA-EBOV infection, which is further enhanced with VSVΔG/EBOV GP treatment. NK cell mediated cytotoxicity and IFN-γ secretion was significantly higher with VSVΔG/EBOV GP treatment. Cell mediated cytotoxicity assays and perforin knockout mice experiments suggest that there are perforin-dependent and -independent mechanisms involved. Together, these data suggest that NK cells play an important role in VSVΔG/EBOV GP-induced protection of EBOV by increasing NK cytotoxicity, and IFN-γ secretion.

  2. [Zika virus infection in pregnancy].

    Science.gov (United States)

    Varjasi, Gabriella; Póka, Róbert

    2017-04-01

    The Zika virus is a flavivirus spread by mosquitoes. Its primary vectors are the Aedes aegypti and the Aedes albopictus. Before 2007 it sporadically caused benign morbidity. Since 2015, it started spreading "explosively" in America, especially in Brazil. In August 2016 they reported cases from New York and Poland, too. Most of the infections don't produce any symptoms, but can cause grave complications. The most important lesion is microcephalia that forms in fetuses. Microcephalia's most serious consequence is mental retardation, which puts great burden on both the family and the society. The viral infection increases the incidence of Guillain-Barré syndrome. This is an acute autoimmune disease which causes demyelination and, in the worst cases, it can also be fatal. Yet we do not possess adequate and specific vaccination nor antiviral therapy, although, since July 2016, the effectiveness of a DNA based vaccine is being tested on humans. More than half of the world's population lives in areas contaminated by infected mosquitoes so there is a great need for the development of an effective method against the vector mosquitoes. Sadly, even the vector control strategies aren't effective enough to push back the epidemic. Pregnant or fertile women must take the highest precautions against mosquito bites, especially if they travel to regions ravaged by the epidemic. The safest solution would be to postpone both the trip and the childbearing. In Europe, the vectors aren't spread enough to cause major threat, except maybe the warmer regions bordered by the Mediterranean Sea. However, it is possible that in the near future other viruses spread by Aedes mosquitoes could appear. Naturally, the travellers and immigrants, who came from endemic regions can also contribute to the spread of the epidemic. Thanks to the changes in global weather, there were reported findings of mosquitoes of the Aedes albopictus species in Hungary, which are slowly invading the continent, although

  3. Proteomic analysis reveals the enhancement of human serum apolipoprotein A-1(APO A-1) in individuals infected with multiple dengue virus serotypes.

    Science.gov (United States)

    Manchala, Nageswar Reddy; Dungdung, Ranjeet; Pilankatta, Rajendra

    2017-10-01

    Human serum protein profiling of the individual infected with multiple dengue virus serotypes for identifying the potential biomarkers and to investigate the cause for the severity of dengue virus infection. Dengue virus NS1-positive serum samples were pooled into two groups (S2 and S3) based on the molecular serotyping and number of heterotypic infections. The pooled serum samples were subjected to two-dimensional gel electrophoresis (2DGE) to identify the differentially expressed proteins. The peptide masses of upregulated protein were detected by matrix-assisted laser desorption-ionisation time-of-flight MALDI-TOF mass spectrometry and analysed by MASCOT search engine. The results were compared with the control group (S1). The commonly upregulated protein was validated by quantitative ELISA and compared with control as well as single serotypic infected samples. Based on 2DGE, total thirteen proteins were differentially upregulated in S2 and S3 groups as compared to control. Some of the upregulated proteins were involved in mediating the complement activation of immune response. The apolipoprotein A-1 (APO A-1) was upregulated in S2 and S3 groups. Upon validation, APO A-1 levels were increased in line with the number of heterotypic infection of dengue viruses. Heterotypic infection of dengue viruses upregulate the serum proteins involved in the complement pathway in the early phase of infection. There was a significant increase in the level of APO A-1 in three different serotypic infections of dengue virus as compared to control. Further, the role of APO-A1 can be explored in elucidating the mechanism of dengue pathogenesis. © 2017 John Wiley & Sons Ltd.

  4. Human immunodeficiency virus (HIV) infection in tuberculosis ...

    African Journals Online (AJOL)

    Human immunodeficiency virus (HIV) infection in tuberculosis patients in Addis ... METHODS: A cross-sectional survey whereby blood sample was collected ... of co-infection appeared to have increased compared to previous studies, 6.6%, ...

  5. Influenza Virus Infection in Nonhuman Primates

    Science.gov (United States)

    Karlsson, Erik A.; Engel, Gregory A.; Feeroz, M.M.; San, Sorn; Rompis, Aida; Lee, Benjamin P. Y.-H.; Shaw, Eric; Oh, Gunwha; Schillaci, Michael A.; Grant, Richard; Heidrich, John; Schultz-Cherry, Stacey

    2012-01-01

    To determine whether nonhuman primates are infected with influenza viruses in nature, we conducted serologic and swab studies among macaques from several parts of the world. Our detection of influenza virus and antibodies to influenza virus raises questions about the role of nonhuman primates in the ecology of influenza. PMID:23017256

  6. Cross-protection or enhanced symptom display in greenhouse tomato co-infected with different Pepino mosaic virus isolates

    NARCIS (Netherlands)

    Hanssen, I.M.; Gutiérrez-Aguirre, I.; Paeleman, A.; Goen, K.; Wittemans, L.; Lievens, B.; Vanachter, A.C.R.C.; Ravnikar, M.; Thomma, B.P.H.J.

    2010-01-01

    The potential of three mild Pepino mosaic virus (PepMV) isolates, belonging to the CH2, EU and LP genotypes, to protect a tomato (Solanum lycopersicum) crop against an aggressive challenge isolate of the CH2 genotype was assessed in greenhouse trials and PepMV symptoms were rated at regular time

  7. Medicinal herbs for hepatitis C virus infection

    DEFF Research Database (Denmark)

    Liu, Jianping; Manheimer, Eric; Tsutani, Kiichiro

    2003-01-01

    The aim of this study was to assess beneficial and harmful effects of medicinal herbs for hepatitis C virus (HCV) infection.......The aim of this study was to assess beneficial and harmful effects of medicinal herbs for hepatitis C virus (HCV) infection....

  8. Persistent hepatitis virus infection and immune homeostasis

    OpenAIRE

    ZHOU Yun

    2014-01-01

    Homeostasis between the host and viruses is naturally maintained. On the one hand, the immune system activates the immune response to kill or eliminate viruses; on the other hand, the immune system controls the immune response to maintain immune homeostasis. The cause of persistent infections with hepatitis viruses such as HBV and HCV is that viral molecules damage the immune system of the host and their variants escape immune clearance. Long-term coexistence of the host and viruses is the pr...

  9. Chikungunya virus infection in travellers to Australia.

    Science.gov (United States)

    Johnson, Douglas F; Druce, Julian D; Chapman, Scott; Swaminathan, Ashwin; Wolf, Josh; Richards, Jack S; Korman, Tony; Birch, Chris; Richards, Michael J

    2008-01-07

    We report eight recent cases of Chikungunya virus infection in travellers to Australia. Patients presented with fevers, rigors, headaches, arthralgia, and rash. The current Indian Ocean epidemic and Italian outbreak have featured prominently on Internet infectious disease bulletins, and Chikungunya virus infection had been anticipated in travellers from the outbreak areas. Diagnosis was by a generic alphavirus reverse transcriptase polymerase chain reaction with confirmatory sequencing. Prompt diagnosis of Chikungunya virus infections is of public health significance as the mosquito vectors for transmission exist in Australia. There is potential for this infection to spread in the largely naïve Australian population.

  10. [Zika virus infection: A review].

    Science.gov (United States)

    Guillier, A; Amazan, E; Aoun, A; Baubion, E; Derancourt, C

    Zika Virus (ZIKV), originally identified in 1947, is a re-emerging Flavivirus transmitted mainly through bites by Aedes mosquitos. Until the recent outbreaks in the Pacific islands and Central and South America, it was known to cause benign disease, in most cases asymptomatic or with mild and nonspecific symptoms (fever, rash, conjunctivitis, arthralgia, etc.). The unprecedented current epidemic has highlighted new modes of transmission (through blood, perinatally and sexually) as well as serious neurological complications such as congenital defects in the fetuses of infected mothers and Guillain-Barre syndrome in adults. This situation, coupled with the threat of worldwide spread, prompted the WHO to declare the ZIKV a public health emergency of international concern in February 2016. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  11. EPIDEMIOLOGY OF THE HERPES SIMPLEX VIRUS INFECTION

    Directory of Open Access Journals (Sweden)

    Ljiljana Kostadinović

    2002-07-01

    Full Text Available Over 150 sorts of viruses are capable of causing diseases of the respiratory ways. The virus infections have become the cost to be paid for urbanization and industrialization. The acute virus infections jeopardize mankind by their complications with numerous consequences. They open up the way to super infections, they provoke endogenous infections and lead to insufficiency of the vital organs. The viruses penetrate the organism mainly through the respiratory ways, digestive and urinary-sexual organs and skin. Some viruses immediately at the place of their entrance into the organism find receptive cells in which they can multiply (herpes virus and etc.. Some viruses must get through the blood, through the lymph or the nerve fibers to the target organs that they have affinity for.The changes that primarily occur in the mouth with manifest lymphadenopathy of the surrounding area emerge with respect to the type of the acute infection dis-ease.The human herpes viruses are responsible for a great number of diseases in people; that is why it can be said that the infections they induce are a very frequent cause of people's diseases in the world. Man is natural and the only host for the types I and II of the herpes simplex virus (HSV; that is why the infected person is regarded as the source of infection. The infection transmission can be by direct contact or over the contaminated secretions during the sexual intercourse. The age and the socioeconomic status (living conditions, level of medical culture, habits, etc. affect to agreat extent epidemiology of the HSV infection. The HSV distribution in the region of Niš in the five-year period (from 1987 to 1992 was the highest in the early and late summer (June and September.

  12. Methamphetamine abuse affects gene expression in brain-derived microglia of SIV-infected macaques to enhance inflammation and promote virus targets

    KAUST Repository

    Najera, Julia A.; Bustamante, Eduardo A.; Bortell, Nikki; Morsey, Brenda; Fox, Howard S.; Ravasi, Timothy; Marcondes, Maria Cecilia Garibaldi

    2016-01-01

    /function of innate immune cells and increase brain viral loads. Here, we examined changes in the gene expression profile of neuron-free microglial cell preparations isolated from the brain of macaques infected with the Simian Immunodeficiency Virus (SIV), a model

  13. Supplementary Material for: Methamphetamine abuse affects gene expression in brain-derived microglia of SIV-infected macaques to enhance inflammation and promote virus targets

    KAUST Repository

    Najera, Julia; Bustamante, Eduardo; Bortell, Nikki; Morsey, Brenda; Fox, Howard; Ravasi, Timothy; Marcondes, Maria

    2016-01-01

    /function of innate immune cells and increase brain viral loads. Here, we examined changes in the gene expression profile of neuron-free microglial cell preparations isolated from the brain of macaques infected with the Simian Immunodeficiency Virus (SIV), a model

  14. Bovine herpes virus infections in cattle.

    Science.gov (United States)

    Nandi, S; Kumar, Manoj; Manohar, M; Chauhan, R S

    2009-06-01

    Bovine herpes virus 1 (BHV-1) is primarily associated with clinical syndromes such as rhinotracheitis, pustular vulvovaginitis and balanoposthitis, abortion, infertility, conjunctivitis and encephalitis in bovine species. The main sources of infection are the nasal exudates and the respiratory droplets, genital secretions, semen, fetal fluids and tissues. The BHV-1 virus can become latent following a primary infection with a field isolate or vaccination with an attenuated strain. The viral genomic DNA has been demonstrated in the sensory ganglia of the trigeminal nerve in infectious bovine rhinotracheitis (IBR) and in sacral spinal ganglia in pustular vulvovaginitis and balanoposthitis cases. BHV-1 infections can be diagnosed by detection of virus or virus components and antibody by serological tests or by detection of genomic DNA by polymerase chain reaction (PCR), nucleic acid hybridization and sequencing. Inactivated vaccines and modified live virus vaccines are used for prevention of BHV-1 infections in cattle; subunit vaccines and marker vaccines are under investigation.

  15. Human Immunodeficiency Virus and Hepatitis C Virus Co-infection ...

    African Journals Online (AJOL)

    Human Immunodeficiency Virus and Hepatitis C Virus Co-infection in Cameroon: Investigation of the Genetic Diversity and Virulent ... AFRICAN JOURNALS ONLINE (AJOL) · Journals · Advanced Search · USING AJOL · RESOURCES ... DNA sequencing, and bioinformatics tools for sequence management and analysis.

  16. Human immunodeficiency virus and hepatitus B virus co-infection ...

    African Journals Online (AJOL)

    Human immunodeficiency virus and hepatitus B virus co-infection amog patients in Kano Nigeria. EE Nwokedi, MA Emokpae, AI Dutse. Abstract. No Abstract. Nigerian Journal of Medicine Vol. 15(3) July-September 2006: 227-229. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD ...

  17. Honey Bee Infecting Lake Sinai Viruses.

    Science.gov (United States)

    Daughenbaugh, Katie F; Martin, Madison; Brutscher, Laura M; Cavigli, Ian; Garcia, Emma; Lavin, Matt; Flenniken, Michelle L

    2015-06-23

    Honey bees are critical pollinators of important agricultural crops. Recently, high annual losses of honey bee colonies have prompted further investigation of honey bee infecting viruses. To better characterize the recently discovered and very prevalent Lake Sinai virus (LSV) group, we sequenced currently circulating LSVs, performed phylogenetic analysis, and obtained images of LSV2. Sequence analysis resulted in extension of the LSV1 and LSV2 genomes, the first detection of LSV4 in the US, and the discovery of LSV6 and LSV7. We detected LSV1 and LSV2 in the Varroa destructor mite, and determined that a large proportion of LSV2 is found in the honey bee gut, suggesting that vector-mediated, food-associated, and/or fecal-oral routes may be important for LSV dissemination. Pathogen-specific quantitative PCR data, obtained from samples collected during a small-scale monitoring project, revealed that LSV2, LSV1, Black queen cell virus (BQCV), and Nosema ceranae were more abundant in weak colonies than strong colonies within this sample cohort. Together, these results enhance our current understanding of LSVs and illustrate the importance of future studies aimed at investigating the role of LSVs and other pathogens on honey bee health at both the individual and colony levels.

  18. Honey Bee Infecting Lake Sinai Viruses

    Directory of Open Access Journals (Sweden)

    Katie F. Daughenbaugh

    2015-06-01

    Full Text Available Honey bees are critical pollinators of important agricultural crops. Recently, high annual losses of honey bee colonies have prompted further investigation of honey bee infecting viruses. To better characterize the recently discovered and very prevalent Lake Sinai virus (LSV group, we sequenced currently circulating LSVs, performed phylogenetic analysis, and obtained images of LSV2. Sequence analysis resulted in extension of the LSV1 and LSV2 genomes, the first detection of LSV4 in the US, and the discovery of LSV6 and LSV7. We detected LSV1 and LSV2 in the Varroa destructor mite, and determined that a large proportion of LSV2 is found in the honey bee gut, suggesting that vector-mediated, food-associated, and/or fecal-oral routes may be important for LSV dissemination. Pathogen-specific quantitative PCR data, obtained from samples collected during a small-scale monitoring project, revealed that LSV2, LSV1, Black queen cell virus (BQCV, and Nosema ceranae were more abundant in weak colonies than strong colonies within this sample cohort. Together, these results enhance our current understanding of LSVs and illustrate the importance of future studies aimed at investigating the role of LSVs and other pathogens on honey bee health at both the individual and colony levels.

  19. Hendra Virus Infection in Dog, Australia, 2013

    OpenAIRE

    Kirkland, Peter D.; Gabor, Melinda; Poe, Ian; Neale, Kristie; Chaffey, Kim; Finlaison, Deborah S.; Gu, Xingnian; Hick, Paul M.; Read, Andrew J.; Wright, Therese; Middleton, Deborah

    2015-01-01

    Hendra virus occasionally causes severe disease in horses and humans. In Australia in 2013, infection was detected in a dog that had been in contact with an infected horse. Abnormalities and viral RNA were found in the dog?s kidney, brain, lymph nodes, spleen, and liver. Dogs should be kept away from infected horses.

  20. Zika Virus: Mechanisms of Infection During Pregnancy.

    Science.gov (United States)

    King, Nicholas J C; Teixeira, Mauro M; Mahalingam, Suresh

    2017-09-01

    Immune status changes during pregnancy, with pro-inflammatory and anti-inflammatory contexts at different stages, making pregnant women potentially more susceptible to various infections. Infection by Zika virus during pregnancy can cause developmental damage to the fetus, and the altered immune response during pregnancy could contribute to disease during Zika infection. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Zika Virus Infection: Current Concerns and Perspectives.

    Science.gov (United States)

    Maharajan, Mari Kannan; Ranjan, Aruna; Chu, Jian Feng; Foo, Wei Lim; Chai, Zhi Xin; Lau, Eileen YinYien; Ye, Heuy Mien; Theam, Xi Jin; Lok, Yen Ling

    2016-12-01

    The Zika virus outbreaks highlight the growing importance need for a reliable, specific and rapid diagnostic device to detect Zika virus, as it is often recognized as a mild disease without being identified. Many Zika virus infection cases have been misdiagnosed or underreported because of the non-specific clinical presentation. The aim of this review was to provide a critical and comprehensive overview of the published peer-reviewed evidence related to clinical presentations, various diagnostic methods and modes of transmission of Zika virus infection, as well as potential therapeutic targets to combat microcephaly. Zika virus is mainly transmitted through bites from Aedes aegypti mosquito. It can also be transmitted through blood, perinatally and sexually. Pregnant women are advised to postpone or avoid travelling to areas where active Zika virus transmission is reported, as this infection is directly linked to foetal microcephaly. Due to the high prevalence of Guillain-Barre syndrome and microcephaly in the endemic area, it is vital to confirm the diagnosis of Zika virus. Zika virus infection had been declared as a public health emergency and of international concern by the World Health Organisation. Governments and agencies should play an important role in terms of investing time and resources to fundamentally understand this infection so that a vaccine can be developed besides raising awareness.

  2. TIM-1 Promotes Hepatitis C Virus Cell Attachment and Infection.

    Science.gov (United States)

    Wang, Jing; Qiao, Luhua; Hou, Zhouhua; Luo, Guangxiang

    2017-01-15

    Human TIM and TAM family proteins were recently found to serve as phosphatidylserine (PS) receptors which promote infections by many different viruses, including dengue virus, West Nile virus, Ebola virus, Marburg virus, and Zika virus. In the present study, we provide substantial evidence demonstrating that TIM-1 is important for efficient infection by hepatitis C virus (HCV). The knockdown of TIM-1 expression significantly reduced HCV infection but not HCV RNA replication. Likewise, TIM-1 knockout in Huh-7.5 cells remarkably lowered HCV cell attachment and subsequent HCV infection. More significantly, the impairment of HCV infection in the TIM-1 knockout cells could be restored completely by ectopic expression of TIM-1 but not TIM-3 or TIM-4. Additionally, HCV infection and cell attachment were inhibited by PS but not by phosphatidylcholine (PC), demonstrating that TIM-1-mediated enhancement of HCV infection is PS dependent. The exposure of PS on the HCV envelope was confirmed by immunoprecipitation of HCV particles with a PS-specific monoclonal antibody. Collectively, these findings demonstrate that TIM-1 promotes HCV infection by serving as an attachment receptor for binding to PS exposed on the HCV envelope. TIM family proteins were recently found to enhance infections by many different viruses, including several members of the Flaviviridae family. However, their importance in HCV infection has not previously been examined experimentally. The TIM family proteins include three members in humans: TIM-1, TIM-3, and TIM-4. The findings derived from our studies demonstrate that TIM-1, but not TIM-3 or TIM-4, promotes HCV infection by functioning as an HCV attachment factor. Knockout of the TIM-1 gene resulted in a remarkable reduction of HCV cell attachment and infection. PS-containing liposomes blocked HCV cell attachment and subsequent HCV infection. HCV particles could also be precipitated with a PS-specific monoclonal antibody. These findings suggest that TIM-1

  3. Prior Exposure to Zika Virus Significantly Enhances Peak Dengue-2 Viremia in Rhesus Macaques

    OpenAIRE

    George, Jeffy; Valiant, William G.; Mattapallil, Mary J.; Walker, Michelle; Huang, Yan-Jang S.; Vanlandingham, Dana L.; Misamore, John; Greenhouse, Jack; Weiss, Deborah E.; Verthelyi, Daniela; Higgs, Stephen; Andersen, Hanne; Lewis, Mark G.; Mattapallil, Joseph J.

    2017-01-01

    Structural and functional homologies between the Zika and Dengue viruses? envelope proteins raise the possibility that cross-reactive antibodies induced following Zika virus infection might enhance subsequent Dengue infection. Using the rhesus macaque model we show that prior infection with Zika virus leads to a significant enhancement of Dengue-2 viremia that is accompanied by neutropenia, lympocytosis, hyperglycemia, and higher reticulocyte counts, along with the activation of pro-inflammat...

  4. Interferon-γ Inhibits Ebola Virus Infection.

    Directory of Open Access Journals (Sweden)

    Bethany A Rhein

    Full Text Available Ebola virus outbreaks, such as the 2014 Makona epidemic in West Africa, are episodic and deadly. Filovirus antivirals are currently not clinically available. Our findings suggest interferon gamma, an FDA-approved drug, may serve as a novel and effective prophylactic or treatment option. Using mouse-adapted Ebola virus, we found that murine interferon gamma administered 24 hours before or after infection robustly protects lethally-challenged mice and reduces morbidity and serum viral titers. Furthermore, we demonstrated that interferon gamma profoundly inhibits Ebola virus infection of macrophages, an early cellular target of infection. As early as six hours following in vitro infection, Ebola virus RNA levels in interferon gamma-treated macrophages were lower than in infected, untreated cells. Addition of the protein synthesis inhibitor, cycloheximide, to interferon gamma-treated macrophages did not further reduce viral RNA levels, suggesting that interferon gamma blocks life cycle events that require protein synthesis such as virus replication. Microarray studies with interferon gamma-treated human macrophages identified more than 160 interferon-stimulated genes. Ectopic expression of a select group of these genes inhibited Ebola virus infection. These studies provide new potential avenues for antiviral targeting as these genes that have not previously appreciated to inhibit negative strand RNA viruses and specifically Ebola virus infection. As treatment of interferon gamma robustly protects mice from lethal Ebola virus infection, we propose that interferon gamma should be further evaluated for its efficacy as a prophylactic and/or therapeutic strategy against filoviruses. Use of this FDA-approved drug could rapidly be deployed during future outbreaks.

  5. Interferon-γ Inhibits Ebola Virus Infection.

    Science.gov (United States)

    Rhein, Bethany A; Powers, Linda S; Rogers, Kai; Anantpadma, Manu; Singh, Brajesh K; Sakurai, Yasuteru; Bair, Thomas; Miller-Hunt, Catherine; Sinn, Patrick; Davey, Robert A; Monick, Martha M; Maury, Wendy

    2015-01-01

    Ebola virus outbreaks, such as the 2014 Makona epidemic in West Africa, are episodic and deadly. Filovirus antivirals are currently not clinically available. Our findings suggest interferon gamma, an FDA-approved drug, may serve as a novel and effective prophylactic or treatment option. Using mouse-adapted Ebola virus, we found that murine interferon gamma administered 24 hours before or after infection robustly protects lethally-challenged mice and reduces morbidity and serum viral titers. Furthermore, we demonstrated that interferon gamma profoundly inhibits Ebola virus infection of macrophages, an early cellular target of infection. As early as six hours following in vitro infection, Ebola virus RNA levels in interferon gamma-treated macrophages were lower than in infected, untreated cells. Addition of the protein synthesis inhibitor, cycloheximide, to interferon gamma-treated macrophages did not further reduce viral RNA levels, suggesting that interferon gamma blocks life cycle events that require protein synthesis such as virus replication. Microarray studies with interferon gamma-treated human macrophages identified more than 160 interferon-stimulated genes. Ectopic expression of a select group of these genes inhibited Ebola virus infection. These studies provide new potential avenues for antiviral targeting as these genes that have not previously appreciated to inhibit negative strand RNA viruses and specifically Ebola virus infection. As treatment of interferon gamma robustly protects mice from lethal Ebola virus infection, we propose that interferon gamma should be further evaluated for its efficacy as a prophylactic and/or therapeutic strategy against filoviruses. Use of this FDA-approved drug could rapidly be deployed during future outbreaks.

  6. Ebola Virus Infection Modelling and Identifiability Problems

    Directory of Open Access Journals (Sweden)

    Van-Kinh eNguyen

    2015-04-01

    Full Text Available The recent outbreaks of Ebola virus (EBOV infections have underlined the impact of the virus as a major threat for human health. Due to the high biosafety classification of EBOV (level 4, basic research is very limited. Therefore, the development of new avenues of thinking to advance quantitative comprehension of the virus and its interaction with the host cells is urgently neededto tackle this lethal disease. Mathematical modelling of the EBOV dynamics can be instrumental to interpret Ebola infection kinetics on quantitative grounds. To the best of our knowledge, a mathematical modelling approach to unravel the interaction between EBOV and the host cells isstill missing. In this paper, a mathematical model based on differential equations is used to represent the basic interactions between EBOV and wild-type Vero cells in vitro. Parameter sets that represent infectivity of pathogens are estimated for EBOV infection and compared with influenza virus infection kinetics. The average infecting time of wild-type Vero cells in EBOV is slower than in influenza infection. Simulation results suggest that the slow infecting time of EBOV could be compensated by its efficient replication. This study reveals several identifiability problems and what kind of experiments are necessary to advance the quantification of EBOV infection. A first mathematical approach of EBOV dynamics and the estimation of standard parametersin viral infections kinetics is the key contribution of this work, paving the way for future modelling work on EBOV infection.

  7. Saffold virus infection associated with human myocarditis

    DEFF Research Database (Denmark)

    Nielsen, Trine Skov; Nielsen, Alex Yde; Banner, Jytte

    2016-01-01

    BACKGROUND: Saffold virus was described in 2007 as one of the first human viruses within the genus cardioviruses. Cardioviruses may cause severe infections of the myocardium in animals, and several studies have associated saffold virus with human disease. As a result, saffold virus has been...... isolated from different anatomical compartments, including the myocardium, but, until now, it has not been possible to demonstrate the accompanying histopathological signs of inflammation. OBJECTIVES: The aim of the study was to examine if saffold virus is capable of causing invasive infection in the human...... myocardium. STUDY DESIGN: Using real-time PCR, we retrospectively examined formalin-fixed paraffin embedded cardiac tissue specimens from 150 deceased individuals diagnosed with myocarditis at autopsy. The results were compared with histological findings. RESULTS AND CONCLUSIONS: Saffold virus was detected...

  8. Spinoculation Enhances HBV Infection in NTCP-Reconstituted Hepatocytes

    Science.gov (United States)

    Yan, Ran; Zhang, Yongmei; Cai, Dawei; Liu, Yuanjie; Cuconati, Andrea; Guo, Haitao

    2015-01-01

    Hepatitis B virus (HBV) infection and its sequelae remain a major public health burden, but both HBV basic research and the development of antiviral therapeutics have been hindered by the lack of an efficient in vitro infection system. Recently, sodium taurocholate cotransporting polypeptide (NTCP) has been identified as the HBV receptor. We herein report that we established a NTCP-complemented HepG2 cell line (HepG2-NTCP12) that supports HBV infection, albeit at a low infectivity level following the reported infection procedures. In our attempts to optimize the infection conditions, we found that the centrifugation of HepG2-NTCP12 cells during HBV inoculation (termed “spinoculation”) significantly enhanced the virus infectivity. Moreover, the infection level gradually increased with accelerated speed of spinoculation up to 1,000g tested. However, the enhancement of HBV infection was not significantly dependent upon the duration of centrifugation. Furthermore, covalently closed circular (ccc) DNA was detected in infected cells under optimized infection condition by conventional Southern blot, suggesting a successful establishment of HBV infection after spinoculation. Finally, the parental HepG2 cells remained uninfected under HBV spinoculation, and HBV entry inhibitors targeting NTCP blocked HBV infection when cells were spinoculated, suggesting the authentic virus entry mechanism is unaltered under centrifugal inoculation. Our data suggest that spinoculation could serve as a standard protocol for enhancing the efficiency of HBV infection in vitro. PMID:26070202

  9. Avian Influenza A Virus Infections in Humans

    Science.gov (United States)

    ... people has ranged from mild to severe. Avian Influenza Transmission Avian Influenza Transmission Infographic [555 KB, 2 pages] Spanish [ ... important for public health. Signs and Symptoms of Avian Influenza A Virus Infections in Humans The reported signs ...

  10. Functional RNA during Zika virus infection

    NARCIS (Netherlands)

    Göertz, Giel P.; Abbo, Sandra R.; Fros, Jelke J.; Pijlman, Gorben P.

    2017-01-01

    Zika virus (ZIKV; family Flaviviridae; genus Flavivirus) is a pathogenic mosquito-borne RNA virus that currently threatens human health in the Americas, large parts of Asia and occasionally elsewhere in the world. ZIKV infection is often asymptomatic but can cause severe symptoms including

  11. Life-Threatening Sochi Virus Infections, Russia

    Science.gov (United States)

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

    2015-01-01

    Sochi virus was recently identified as a new hantavirus genotype carried by the Black Sea field mouse, Apodemus ponticus. We evaluated 62 patients in Russia with Sochi virus infection. Most clinical cases were severe, and the case-fatality rate was as high as 14.5%. PMID:26584463

  12. Chikungunya Virus Infection of Aedes Mosquitoes.

    Science.gov (United States)

    Wong, Hui Vern; Chan, Yoke Fun; Sam, I-Ching; Sulaiman, Wan Yusof Wan; Vythilingam, Indra

    2016-01-01

    In vivo infection of mosquitoes is an important method to study and characterize arthropod-borne viruses. Chikungunya virus (CHIKV) is a mosquito-borne alphavirus that is transmitted primarily by Aedes mosquitoes. In this chapter, we describe a protocol for infection of CHIKV in two species of Aedes mosquitoes, Aedes aegypti and Aedes albopictus, together with the isolation of CHIKV in different parts of the infected mosquito such as midgut, legs, wings, salivary gland, head, and saliva. This allows the study of viral infection, replication and dissemination within the mosquito vector.

  13. Hepatitis C virus infection in the human immunodeficiency virus infected patient

    DEFF Research Database (Denmark)

    Clausen, Louise Nygaard; Lundbo, Lene Fogt; Benfield, Thomas

    2014-01-01

    Human immunodeficiency virus (HIV) and hepatitis C virus (HCV) share the same transmission routes; therefore, coinfection is frequent. An estimated 5-10 million individuals alone in the western world are infected with both viruses. The majority of people acquire HCV by injection drug use and...

  14. Inhibition of enveloped viruses infectivity by curcumin.

    Directory of Open Access Journals (Sweden)

    Tzu-Yen Chen

    Full Text Available Curcumin, a natural compound and ingredient in curry, has antiinflammatory, antioxidant, and anticarcinogenic properties. Previously, we reported that curcumin abrogated influenza virus infectivity by inhibiting hemagglutination (HA activity. This study demonstrates a novel mechanism by which curcumin inhibits the infectivity of enveloped viruses. In all analyzed enveloped viruses, including the influenza virus, curcumin inhibited plaque formation. In contrast, the nonenveloped enterovirus 71 remained unaffected by curcumin treatment. We evaluated the effects of curcumin on the membrane structure using fluorescent dye (sulforhodamine B; SRB-containing liposomes that mimic the viral envelope. Curcumin treatment induced the leakage of SRB from these liposomes and the addition of the influenza virus reduced the leakage, indicating that curcumin disrupts the integrity of the membranes of viral envelopes and of liposomes. When testing liposomes of various diameters, we detected higher levels of SRB leakage from the smaller-sized liposomes than from the larger liposomes. Interestingly, the curcumin concentration required to reduce plaque formation was lower for the influenza virus (approximately 100 nm in diameter than for the pseudorabies virus (approximately 180 nm and the vaccinia virus (roughly 335 × 200 × 200 nm. These data provide insights on the molecular antiviral mechanisms of curcumin and its potential use as an antiviral agent for enveloped viruses.

  15. Inhibition of Enveloped Viruses Infectivity by Curcumin

    Science.gov (United States)

    Wen, Hsiao-Wei; Ou, Jun-Lin; Chiou, Shyan-Song; Chen, Jo-Mei; Wong, Min-Liang; Hsu, Wei-Li

    2013-01-01

    Curcumin, a natural compound and ingredient in curry, has antiinflammatory, antioxidant, and anticarcinogenic properties. Previously, we reported that curcumin abrogated influenza virus infectivity by inhibiting hemagglutination (HA) activity. This study demonstrates a novel mechanism by which curcumin inhibits the infectivity of enveloped viruses. In all analyzed enveloped viruses, including the influenza virus, curcumin inhibited plaque formation. In contrast, the nonenveloped enterovirus 71 remained unaffected by curcumin treatment. We evaluated the effects of curcumin on the membrane structure using fluorescent dye (sulforhodamine B; SRB)-containing liposomes that mimic the viral envelope. Curcumin treatment induced the leakage of SRB from these liposomes and the addition of the influenza virus reduced the leakage, indicating that curcumin disrupts the integrity of the membranes of viral envelopes and of liposomes. When testing liposomes of various diameters, we detected higher levels of SRB leakage from the smaller-sized liposomes than from the larger liposomes. Interestingly, the curcumin concentration required to reduce plaque formation was lower for the influenza virus (approximately 100 nm in diameter) than for the pseudorabies virus (approximately 180 nm) and the vaccinia virus (roughly 335 × 200 × 200 nm). These data provide insights on the molecular antiviral mechanisms of curcumin and its potential use as an antiviral agent for enveloped viruses. PMID:23658730

  16. Hepatitis C Virus Infection in Nigerians | Ejiofor | Nigerian Medical ...

    African Journals Online (AJOL)

    Background: Hepatitis C virus is a chronic life long infection in the majority of patients who are infected with the virus. Not much is known and written/published about this virus in Nigeria. Objective: To asses the status of hepatitis C virus infection in Nigeria. Materials and method: Sources of information were mainly from ...

  17. Role of natural killer cells in innate protection against lethal ebola virus infection.

    Science.gov (United States)

    Warfield, Kelly L; Perkins, Jeremy G; Swenson, Dana L; Deal, Emily M; Bosio, Catharine M; Aman, M Javad; Yokoyama, Wayne M; Young, Howard A; Bavari, Sina

    2004-07-19

    Ebola virus is a highly lethal human pathogen and is rapidly driving many wild primate populations toward extinction. Several lines of evidence suggest that innate, nonspecific host factors are potentially critical for survival after Ebola virus infection. Here, we show that nonreplicating Ebola virus-like particles (VLPs), containing the glycoprotein (GP) and matrix protein virus protein (VP)40, administered 1-3 d before Ebola virus infection rapidly induced protective immunity. VLP injection enhanced the numbers of natural killer (NK) cells in lymphoid tissues. In contrast to live Ebola virus, VLP treatment of NK cells enhanced cytokine secretion and cytolytic activity against NK-sensitive targets. Unlike wild-type mice, treatment of NK-deficient or -depleted mice with VLPs had no protective effect against Ebola virus infection and NK cells treated with VLPs protected against Ebola virus infection when adoptively transferred to naive mice. The mechanism of NK cell-mediated protection clearly depended on perforin, but not interferon-gamma secretion. Particles containing only VP40 were sufficient to induce NK cell responses and provide protection from infection in the absence of the viral GP. These findings revealed a decisive role for NK cells during lethal Ebola virus infection. This work should open new doors for better understanding of Ebola virus pathogenesis and direct the development of immunotherapeutics, which target the innate immune system, for treatment of Ebola virus infection.

  18. Cowpea viruses: Effect of single and mixed infections on symptomatology and virus concentration

    Directory of Open Access Journals (Sweden)

    Nsa Imade Y

    2007-09-01

    Full Text Available Abstract Natural multiple viral infections of cultivated cowpeas have been reported in Nigeria. In this study, three Nigerian commercial cowpea cultivars ("Olo 11", "Oloyin" and "White" and two lines from the IITA (IT86D- 719 and TVU 76 were mechanically inoculated with Cowpea aphid-borne mosaic virus (CABMV, Bean southern mosaic virus (SBMV and Cowpea mottle virus (CMeV singly, as well as in all possible combinations at 10, 20 and 30 days after planting (DAP. Samples of leaves or stems were collected at 10, 20 and 30 days after inoculation (DAI and analyzed for relative virus concentration by Enzyme-Linked Immunosrbent Assay. All the cultivars and lines {CVS/L} were susceptible to the viruses but the commercial CVS showed more severe symptoms and had relatively higher viral concentration. In single virus infections, CABMV which induced the most severe symptoms had absorbance values (at 405 nm of 0.11 to 0.46 while SBMV and CMeV which induced moderate symptoms had virus titre of 0.74 to 1.99 and 0.11 to 0.90 respectively. Plants inoculated 10 DAP had significantly higher virus concentration than those inoculated 30 DAP. In mixed infections involving CABMV (10 DAP apical necrosis and death were observed in commercial cultivars "Olo 11" and "White". Enhancement of CMeV titers were observed in plants infected with CMeV + CABMV. Multiple viral infections of cowpeas may result in complete yield loss, hence, the availability of seeds of cultivars with a high level of multiple virus resistance is recommended as a means of control.

  19. Early infections by myxoma virus of young rabbits (Oryctolagus cuniculus) protected by maternal antibodies activate their immune system and enhance herd immunity in wild populations.

    Science.gov (United States)

    Marchandeau, Stéphane; Pontier, Dominique; Guitton, Jean-Sébastien; Letty, Jérôme; Fouchet, David; Aubineau, Jacky; Berger, Francis; Léonard, Yves; Roobrouck, Alain; Gelfi, Jacqueline; Peralta, Brigitte; Bertagnoli, Stéphane

    2014-03-04

    The role of maternal antibodies is to protect newborns against acute early infection by pathogens. This can be achieved either by preventing any infection or by allowing attenuated infections associated with activation of the immune system, the two strategies being based on different cost/benefit ratios. We carried out an epidemiological survey of myxomatosis, which is a highly lethal infectious disease, in two distant wild populations of rabbits to describe the epidemiological pattern of the disease. Detection of specific IgM and IgG enabled us to describe the pattern of immunity. We show that maternal immunity attenuates early infection of juveniles and enables activation of their immune system. This mechanism associated with steady circulation of the myxoma virus in both populations, which induces frequent reinfections of immune rabbits, leads to the maintenance of high immunity levels within populations. Thus, myxomatosis has a low impact, with most infections being asymptomatic. This work shows that infection of young rabbits protected by maternal antibodies induces attenuated disease and activates their immune system. This may play a major role in reducing the impact of a highly lethal disease when ecological conditions enable permanent circulation of the pathogen.

  20. Pneumothorax in human immunodeficiency virus infection

    Directory of Open Access Journals (Sweden)

    Sibes Kumar Das

    2015-01-01

    Full Text Available Pneumothorax occurs more frequently in people with Human immunodeficiency virus infection in comparison with the general population. In most cases it is secondary the underlying pulmonary disorder, especially pulmonary infections. Though Pneumocystis jiroveci pneumonia is most common pulmonary infection associated with pneumothorax, other infections, non-infective etiology and iatrogenic causes are also encountered. Pneumothorax in these patients are associated with persistent bronchopleural fistula, prolonged hospital stay, poor success with intercostal tube drain, frequent requirement of surgical intervention and increased mortality. Optimal therapeutic approach in these patients is still not well-defined.

  1. Infection of phytoplankton by aerosolized marine viruses

    Science.gov (United States)

    Sharoni, Shlomit; Trainic, Miri; Schatz, Daniella; Lehahn, Yoav; Flores, Michel J.; Bidle, Kay D.; Ben-Dor, Shifra; Rudich, Yinon; Vardi, Assaf

    2015-01-01

    Marine viruses constitute a major ecological and evolutionary driving force in the marine ecosystems. However, their dispersal mechanisms remain underexplored. Here we follow the dynamics of Emiliania huxleyi viruses (EhV) that infect the ubiquitous, bloom-forming phytoplankton E. huxleyi and show that EhV are emitted to the atmosphere as primary marine aerosols. Using a laboratory-based setup, we showed that the dynamic of EhV aerial emission is strongly coupled to the host–virus dynamic in the culture media. In addition, we recovered EhV DNA from atmospheric samples collected over an E. huxleyi bloom in the North Atlantic, providing evidence for aerosolization of marine viruses in their natural environment. Decay rate analysis in the laboratory revealed that aerosolized viruses can remain infective under meteorological conditions prevailing during E. huxleyi blooms in the ocean, allowing potential dispersal and infectivity over hundreds of kilometers. Based on the combined laboratory and in situ findings, we propose that atmospheric transport of EhV is an effective transmission mechanism for spreading viral infection over large areas in the ocean. This transmission mechanism may also have an important ecological impact on the large-scale host–virus “arms race” during bloom succession and consequently the turnover of carbon in the ocean. PMID:25964340

  2. [Epidemiologic aspects of human immunodeficiency virus and hepatitis virus infections].

    Science.gov (United States)

    Diarra, M; Konate, A; Minta, D; Sounko, A; Dembele, M; Toure, C S; Kalle, A; Traore, H H; Maiga, M Y

    2006-01-01

    In order to determinate the prevalence of hepatitis B virus and hepatitis C virus among patients infected by the HIV, We realized a transverse survey case--control in hepato-gastro-enterological ward and serology unity of National Institute of Research in Public health (INRSP). Our sample was constituted with 100 patients HIV positive compared to 100 controls HIV negative. The viral markers research has been made by methods immuno-enzymatiqueses of ELISA 3rd generation. Tests permitted to get the following results: Hepatitis B surface antigen (HBs Ag) was positive among 21% with patients HIV positive versus 23% among control (p = 0,732); Antibody to hepatitis C virus (anti-HCV ab) was present among 23% with patients HIV positive versus 0% among control (p <0,05). Female was predominant among co-infections patient, but without statistic link (p = 0,9 and p = 0,45); The co-infection HBV- HCV was significatively linked to age beyond 40 years (p = 0,0005). Co-infections with HIV infection and hepatitis virus are not rare and deserve to be investigated.

  3. Aedes aegypti D7 Saliva Protein Inhibits Dengue Virus Infection.

    Directory of Open Access Journals (Sweden)

    Michael J Conway

    2016-09-01

    Full Text Available Aedes aegypti is the primary vector of several medically relevant arboviruses including dengue virus (DENV types 1-4. Ae. aegypti transmits DENV by inoculating virus-infected saliva into host skin during probing and feeding. Ae. aegypti saliva contains over one hundred unique proteins and these proteins have diverse functions, including facilitating blood feeding. Previously, we showed that Ae. aegypti salivary gland extracts (SGEs enhanced dissemination of DENV to draining lymph nodes. In contrast, HPLC-fractionation revealed that some SGE components inhibited infection. Here, we show that D7 proteins are enriched in HPLC fractions that are inhibitory to DENV infection, and that recombinant D7 protein can inhibit DENV infection in vitro and in vivo. Further, binding assays indicate that D7 protein can directly interact with DENV virions and recombinant DENV envelope protein. These data reveal a novel role for D7 proteins, which inhibits arbovirus transmission to vertebrates through a direct interaction with virions.

  4. Hepatitis C virus infection in HIV-infected patients.

    Science.gov (United States)

    Sulkowski, Mark S

    2007-10-01

    The hepatitis C virus (HCV) is a spherical enveloped RNA virus of the Flaviviridae family, classified within the Hepacivirus genus. Since its discovery in 1989, HCV has been recognized as a major cause of chronic hepatitis and hepatic fibrosis that progresses in some patients to cirrhosis and hepatocellular carcinoma. In the United States, approximately 4 million people have been infected with HCV, and 10,000 HCVrelated deaths occur each year. Due to shared routes of transmission, HCV and HIV co-infection are common, affecting approximately one third of all HIV-infected persons in the United States. In addition, HIV co-infection is associated with higher HCV RNA viral load and a more rapid progression of HCV-related liver disease, leading to an increased risk of cirrhosis. HCV infection may also impact the course and management of HIV disease, particularly by increasing the risk of antiretroviral drug-induced hepatotoxicity. Thus, chronic HCV infection acts as an opportunistic disease in HIV-infected persons because the incidence of infection is increased and the natural history of HCV infection is accelerated in co-infected persons. Strategies to prevent primary HCV infection and to modify the progression of HCV-related liver disease are urgently needed among HIV/HCV co-infected individuals.

  5. Infection of neuroblastoma cells by rabies virus is modulated by the virus titer.

    Science.gov (United States)

    Fuoco, Natalia Langenfeld; Dos Ramos Silva, Sandriana; Fernandes, Elaine Raniero; Luiz, Fernanda Guedes; Ribeiro, Orlando Garcia; Katz, Iana Suly Santos

    2018-01-01

    Rabies is a lethal viral infection that can affect almost all mammals, including humans. To better understand the replication of Rabies lyssavirus, we investigated if the viral load in brains naturally infected with rabies influences viral internalization and viral growth kinetics in neuroblastoma cells, and if the viral load affects mortality in mice after intradermal infection. We noted that high initial viral loads in brains (group II) were unfavourable for increasing viral titers during serial passages in neuroblastoma cells when compared to low initial viral loads in brains (group I). In addition, group I strains showed higher viral growth and enhanced internalization efficiency in neuroblastoma cells than group II strains. However, we observed that the dominant virus subpopulation in group II promoted efficient viral infection in the central nervous system in the new host, providing a selective advantage to the virus. Our data indicate that rabies infection in animal models depends on not only the virus strain but also the amount of virus. This study may serve as a basis for understanding the biologic proprieties of Rabies lyssavirus strains with respect to the effects on viral replication and the impact on pathogenesis, improving virus yields for use in vaccine development. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. [Contemporary threat of influenza virus infection].

    Science.gov (United States)

    Płusa, Tadeusz

    2010-01-01

    Swine-origine H1N1 influenza virus (S-OIV) caused a great mobilization of health medical service over the world. Now it is well known that a vaccine against novel virus is expected as a key point in that battle. In the situation when recommended treatment with neuraminidase inhibitors is not sufficient to control influenza A/H1N1 viral infection the quick and precisely diagnostic procedures should be applied to save and protect our patients.

  7. Inhibition of Neurogenesis by Zika virus Infection.

    Science.gov (United States)

    Ahmad, Fahim; Siddiqui, Amna; Kamal, Mohammad A; Sohrab, Sayed S

    2018-02-01

    The association between Zika virus infection and neurological disorder has raised urgent global alarm. The ongoing epidemic has triggered quick responses in the scientific community. The first case of Zika virus was reported in 2015 from Brazil and now has spread over 30 countries. Nearly four hundred cases of travel-associated Zika virus infection have also been reported in the United States. Zika virus is primarily transmitted by mosquito belongs to the genus Aedes that are widely distributed throughout the world including the Southern United States. Additionally, the virus can also be transmitted from males to females by sexual contact. The epidemiological investigations during the current outbreak found a causal link between infection in pregnant women and development of microcephaly in their unborn babies. This finding is a cause for grave concern since microcephaly is a serious neural developmental disorder that can lead to significant post-natal developmental abnormalities and disabilities. Recently, published data indicate that Zika virus infection affects the growth of fetal neural progenitor cells and cerebral neurons that results in malformation of cerebral cortex leading to microcephaly. Recently, it has been reported that Zika virus infection deregulates the signaling pathway of neuronal cell and inhibit the neurogenesis resulting into dementia. In this review we have discussed about the information about cellular and molecular mechanisms in neurodegeneration of human neuronal cells and inhibit the neurogenesis. Additionally, this information will be very helpful further not only in neuro-scientific research but also designing and development of management strategies for microcephaly and other mosquito borne disease. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  8. Hepatitis C virus infection in nephrology patients.

    Science.gov (United States)

    Rostaing, Lionel; Izopet, Jacques; Kamar, Nassim

    2013-10-01

    Hepatitis C virus (HCV) infection leads to chronic liver disease, but also to extra-hepatic manifestations. Directory of Open Access Journals (DOAJ), Google Scholar, Pubmed (NLM), LISTA (EBSCO) and Web of Science have been searched. Herein, we provide an overview of renal diseases related to HCV and their therapies, as well as the treatment options available for HCV (+)/RNA (+) dialysis patients. We will not mention, however, HCV infection-related complications in the post-kidney transplantation setting. Extra-hepatic manifestations of HCV infection include mixed cryoglobulinemia, lymphoproliferative disorders, and renal disease. HCV infection has been reported in association with distinct histological patterns of glomerulonephritis in native kidneys.

  9. Dendritic cells during Epstein Barr virus infection

    Directory of Open Access Journals (Sweden)

    Christian eMunz

    2014-06-01

    Full Text Available Epstein Barr virus (EBV causes persistent infection in more than 90% of the human adult population and is associated with 2% of all tumors in humans. This -herpesvirus infects primarily human B and epithelial cells, but has been reported to be sensed by dendritic cells (DCs during primary infection. These activated DCs are thought to contribute to innate restriction of EBV infection and initiate EBV specific adaptive immune responses via cross-priming. The respective evidence and their potential importance for EBV specific vaccine development will be discussed in this review.

  10. Zika virus infection confers protection against West Nile virus challenge in mice.

    Science.gov (United States)

    Vázquez-Calvo, Ángela; Blázquez, Ana-Belén; Escribano-Romero, Estela; Merino-Ramos, Teresa; Saiz, Juan-Carlos; Martín-Acebes, Miguel A; Jiménez de Oya, Nereida

    2017-09-20

    Flaviviruses are RNA viruses that constitute a worrisome threat to global human and animal health. Zika virus (ZIKV), which was initially reported to cause a mild disease, recently spread in the Americas, infecting millions of people. During this recent epidemic, ZIKV infection has been linked to serious neurological diseases and birth defects, specifically Guillain-Barrè syndrome (GBS) and microcephaly. Because information about ZIKV immunity remains scarce, we assessed the humoral response of immunocompetent mice to infection with three viral strains of diverse geographical origin (Africa, Asia and America). No infected animals showed any sign of disease or died after infection. However, specific neutralizing antibodies were elicited in all infected mice. Considering the rapid expansion of ZIKV throughout the American continent and its co-circulation with other medically relevant flaviviruses, such as West Nile virus (WNV), the induction of protective immunity between ZIKV and WNV was analyzed. Remarkably, protection after challenge with WNV was observed in mice previously infected with ZIKV, as survival rates were significantly higher than in control mice. Moreover, previous ZIKV infection enhanced the humoral immune response against WNV. These findings may be relevant in geographical areas where both ZIKV and WNV co-circulate, as well as for the future development of broad-spectrum flavivirus vaccines.

  11. The impact of hepatitis A virus infection on hepatitis C virus infection: a competitive exclusion hypothesis.

    Science.gov (United States)

    Amaku, Marcos; Coutinho, Francisco Antonio Bezerra; Chaib, Eleazar; Massad, Eduardo

    2013-01-01

    We address the observation that, in some cases, patients infected with the hepatitis C virus (HCV) are cleared of HCV when super-infected with the hepatitis A virus (HAV). We hypothesise that this phenomenon can be explained by the competitive exclusion principle, including the action of the immune system, and show that the inclusion of the immune system explains both the elimination of one virus and the co-existence of both infections for a certain range of parameters. We discuss the potential clinical implications of our findings.

  12. Infection of potato mesophyll protoplasts with five plant viruses.

    Science.gov (United States)

    Barker, H; Harrison, B D

    1982-12-01

    Methods are described for preparing potato mesophyll protoplasts that are suitable for infection with inocula of virus nucleoprotein or RNA. The protoplasts could be infected with four sap-transmissible viruses (tobacco mosaic, tobacco rattle, tobacco ringspot and tomato black ring viruses) and with potato leafroll virus, which is not saptransmissible. No differences were observed in ability to infect protoplasts with potato leafroll virus strains differing either in virulence in intact plants or in aphid transmissibility.

  13. Hepatitis C virus infection and risk of coronary artery disease

    DEFF Research Database (Denmark)

    Roed, Torsten; Lebech, Anne-Mette; Kjaer, Andreas

    2012-01-01

    Several chronic infections have been associated with cardiovascular diseases, including Chlamydia pneumoniae, human immunodeficiency virus and viral hepatitis. This review evaluates the literature on the association between chronic hepatitis C virus (HCV) infection and the risk of coronary artery...

  14. Activity of andrographolide against chikungunya virus infection.

    Science.gov (United States)

    Wintachai, Phitchayapak; Kaur, Parveen; Lee, Regina Ching Hua; Ramphan, Suwipa; Kuadkitkan, Atichat; Wikan, Nitwara; Ubol, Sukathida; Roytrakul, Sittiruk; Chu, Justin Jang Hann; Smith, Duncan R

    2015-09-18

    Chikungunya virus (CHIKV) is a re-emerging mosquito-borne alphavirus that has recently engendered large epidemics around the world. There is no specific antiviral for treatment of patients infected with CHIKV, and development of compounds with significant anti-CHIKV activity that can be further developed to a practical therapy is urgently required. Andrographolide is derived from Andrographis paniculata, a herb traditionally used to treat a number of conditions including infections. This study sought to determine the potential of andrographolide as an inhibitor of CHIKV infection. Andrographolide showed good inhibition of CHIKV infection and reduced virus production by approximately 3log10 with a 50% effective concentration (EC50) of 77 μM without cytotoxicity. Time-of-addition and RNA transfection studies showed that andrographolide affected CHIKV replication and the activity of andrographolide was shown to be cell type independent. This study suggests that andrographolide has the potential to be developed further as an anti-CHIKV therapeutic agent.

  15. Activity of andrographolide against chikungunya virus infection

    OpenAIRE

    Phitchayapak Wintachai; Parveen Kaur; Regina Ching Hua Lee; Suwipa Ramphan; Atichat Kuadkitkan; Nitwara Wikan; Sukathida Ubol; Sittiruk Roytrakul; Justin Jang Hann Chu; Duncan R. Smith

    2015-01-01

    Chikungunya virus (CHIKV) is a re-emerging mosquito-borne alphavirus that has recently engendered large epidemics around the world. There is no specific antiviral for treatment of patients infected with CHIKV, and development of compounds with significant anti-CHIKV activity that can be further developed to a practical therapy is urgently required. Andrographolide is derived from Andrographis paniculata, a herb traditionally used to treat a number of conditions including infections. This stud...

  16. Zika virus infection of Hofbauer cells.

    Science.gov (United States)

    Simoni, Michael K; Jurado, Kellie Ann; Abrahams, Vikki M; Fikrig, Erol; Guller, Seth

    2017-02-01

    Recent studies have linked antenatal infection with Zika virus (ZIKV) with major adverse fetal and neonatal outcomes, including microcephaly. There is a growing consensus for the existence of a congenital Zika syndrome (CZS). Previous studies have indicated that non-placental macrophages play a key role in the replication of dengue virus (DENV), a closely related flavivirus. As the placenta provides the conduit for vertical transmission of certain viruses, and placental Hofbauer cells (HBCs) are fetal-placental macrophages located adjacent to fetal capillaries, it is not surprising that several recent studies have examined infection of HBCs by ZIKV. In this review, we describe congenital abnormalities associated with ZIKV infection, the role of HBCs in the placental response to infection, and evidence for the susceptibility of HBCs to ZIKV infection. We conclude that HBCs may contribute to the spread of ZIKV in placenta and promote vertical transmission of ZIKV, ultimately compromising fetal and neonatal development and function. Current evidence strongly suggests that further studies are warranted to dissect the specific molecular mechanism through which ZIKV infects HBCs and its potential impact on the development of CZS. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  17. Protective Effect of Dietary Xylitol on Influenza A Virus Infection

    Science.gov (United States)

    Yin, Sun Young; Kim, Hyoung Jin; Kim, Hong-Jin

    2014-01-01

    Xylitol has been used as a substitute for sugar to prevent cavity-causing bacteria, and most studies have focused on its benefits in dental care. Meanwhile, the constituents of red ginseng (RG) are known to be effective in ameliorating the symptoms of influenza virus infection when they are administered orally for 14 days. In this study, we investigated the effect of dietary xylitol on influenza A virus infection (H1N1). We designed regimens containing various fractions of RG (RGs: whole extract, water soluble fraction, saponin and polysaccharide) and xylitol, and combination of xylitol with the RG fractions. Mice received the various combinations orally for 5 days prior to lethal influenza A virus infection. Almost all the mice died post challenge when xylitol or RGs were administered separately. Survival was markedly enhanced when xylitol was administered along with RGs, pointing to a synergistic effect. The effect of xylitol plus RG fractions increased with increasing dose of xylitol. Moreover, dietary xylitol along with the RG water soluble fraction significantly reduced lung virus titers after infection. Therefore, we suggest that dietary xylitol is effective in ameliorating influenza-induced symptoms when it is administered with RG fractions, and this protective effect of xylitol should be considered in relation to other diseases. PMID:24392148

  18. Protective effect of dietary xylitol on influenza A virus infection.

    Directory of Open Access Journals (Sweden)

    Sun Young Yin

    Full Text Available Xylitol has been used as a substitute for sugar to prevent cavity-causing bacteria, and most studies have focused on its benefits in dental care. Meanwhile, the constituents of red ginseng (RG are known to be effective in ameliorating the symptoms of influenza virus infection when they are administered orally for 14 days. In this study, we investigated the effect of dietary xylitol on influenza A virus infection (H1N1. We designed regimens containing various fractions of RG (RGs: whole extract, water soluble fraction, saponin and polysaccharide and xylitol, and combination of xylitol with the RG fractions. Mice received the various combinations orally for 5 days prior to lethal influenza A virus infection. Almost all the mice died post challenge when xylitol or RGs were administered separately. Survival was markedly enhanced when xylitol was administered along with RGs, pointing to a synergistic effect. The effect of xylitol plus RG fractions increased with increasing dose of xylitol. Moreover, dietary xylitol along with the RG water soluble fraction significantly reduced lung virus titers after infection. Therefore, we suggest that dietary xylitol is effective in ameliorating influenza-induced symptoms when it is administered with RG fractions, and this protective effect of xylitol should be considered in relation to other diseases.

  19. Hepatitis C Virus Infection In Nigerianswith Diabetesmellitus ...

    African Journals Online (AJOL)

    Background/Aims: Studies from mainly Caucasian populations have shown epidemiological evidence of an association between diabetes mellitus and Hepatitis C virus (HCV) infection. The aim of this study was to determine whether any such association exists in a black African population with diabetes mellitus. Method: ...

  20. Immunodomination during peripheral vaccinia virus infection.

    Directory of Open Access Journals (Sweden)

    Leon C W Lin

    Full Text Available Immunodominance is a fundamental property of CD8(+ T cell responses to viruses and vaccines. It had been observed that route of administration alters immunodominance after vaccinia virus (VACV infection, but only a few epitopes were examined and no mechanism was provided. We re-visited this issue, examining a panel of 15 VACV epitopes and four routes, namely intradermal (i.d., subcutaneous (s.c., intraperitoneal (i.p. and intravenous (i.v. injection. We found that immunodominance is sharpened following peripheral routes of infection (i.d. and s.c. compared with those that allow systemic virus dissemination (i.p. and i.v.. This increased immunodominance was demonstrated with native epitopes of VACV and with herpes simplex virus glycoprotein B when expressed from VACV. Responses to some subdominant epitopes were altered by as much as fourfold. Tracking of virus, examination of priming sites, and experiments restricting virus spread showed that priming of CD8(+ T cells in the spleen was necessary, but not sufficient to broaden responses. Further, we directly demonstrated that immunodomination occurs more readily when priming is mainly in lymph nodes. Finally, we were able to reduce immunodominance after i.d., but not i.p. infection, using a VACV expressing the costimulators CD80 (B7-1 and CD86 (B7-2, which is notable because VACV-based vaccines incorporating these molecules are in clinical trials. Taken together, our data indicate that resources for CD8(+ T cell priming are limiting in local draining lymph nodes, leading to greater immunodomination. Further, we provide evidence that costimulation can be a limiting factor that contributes to immunodomination. These results shed light on a possible mechanism of immunodomination and highlight the need to consider multiple epitopes across the spectrum of immunogenicities in studies aimed at understanding CD8(+ T cell immunity to viruses.

  1. A novel Cre recombinase imaging system for tracking lymphotropic virus infection in vivo.

    Directory of Open Access Journals (Sweden)

    Bernadette M Dutia

    2009-08-01

    Full Text Available Detection, isolation, and identification of individual virus infected cells during long term infection are critical to advance our understanding of mechanisms of pathogenesis for latent/persistent viruses. However, current approaches to study these viruses in vivo have been hampered by low sensitivity and effects of cell-type on expression of viral encoded reporter genes. We have designed a novel Cre recombinase (Cre-based murine system to overcome these problems, and thereby enable tracking and isolation of individual in vivo infected cells.Murine gammaherpesvirus 68 (MHV-68 was used as a prototypic persistent model virus. A Cre expressing recombinant virus was constructed and characterised. The virus is attenuated both in lytic virus replication, producing ten-fold lower lung virus titres than wild type virus, and in the establishment of latency. However, despite this limitation, when the sEGFP7 mouse line containing a Cre-activated enhanced green fluorescent protein (EGFP was infected with the Cre expressing virus, sites of latent and persistent virus infection could be identified within B cells and macrophages of the lymphoid system on the basis of EGFP expression. Importantly, the use of the sEGFP7 mouse line which expresses high levels of EGFP allowed individual virus positive cells to be purified by FACSorting. Virus gene expression could be detected in these cells. Low numbers of EGFP positive cells could also be detected in the bone marrow.The use of this novel Cre-based virus/mouse system allowed identification of individual latently infected cells in vivo and may be useful for the study and long-term monitoring of other latent/persistent virus infections.

  2. Cells in Dengue Virus Infection In Vivo

    Directory of Open Access Journals (Sweden)

    Sansanee Noisakran

    2010-01-01

    Full Text Available Dengue has been recognized as one of the most important vector-borne emerging infectious diseases globally. Though dengue normally causes a self-limiting infection, some patients may develop a life-threatening illness, dengue hemorrhagic fever (DHF/dengue shock syndrome (DSS. The reason why DHF/DSS occurs in certain individuals is unclear. Studies in the endemic regions suggest that the preexisting antibodies are a risk factor for DHF/DSS. Viremia and thrombocytopenia are the key clinical features of dengue virus infection in patients. The amounts of virus circulating in patients are highly correlated with severe dengue disease, DHF/DSS. Also, the disturbance, mainly a transient depression, of hematological cells is a critical clinical finding in acute dengue patients. However, the cells responsible for the dengue viremia are unresolved in spite of the intensive efforts been made. Dengue virus appears to replicate and proliferate in many adapted cell lines, but these in vitro properties are extremely difficult to be reproduced in primary cells or in vivo. This paper summarizes reports on the permissive cells in vitro and in vivo and suggests a hematological cell lineage for dengue virus infection in vivo, with the hope that a new focus will shed light on further understanding of the complexities of dengue disease.

  3. Animal model for hepatitis C virus infection.

    Science.gov (United States)

    Tsukiyama-Kohara, Kyoko; Kohara, Michinori

    2015-01-01

    Hepatitis C virus (HCV) infects more than 170 million people in the world and chronic HCV infection develops into cirrhosis and hepatocellular carcinoma (HCC). Recently, the effective compounds have been approved for HCV treatment, the protease inhibitor and polymerase inhibitor (direct acting antivirals; DAA). DAA-based therapy enabled to cure from HCV infection. However, development of new drug and vaccine is still required because of the generation of HCV escape mutants from DAA, development of HCC after treatment of DAA, and the high cost of DAA. In order to develop new anti-HCV drug and vaccine, animal infection model of HCV is essential. In this manuscript, we would like to introduce the history and the current status of the development of HCV animal infection model.

  4. Interferon production and immune response induction in pathogenic rabies virus-infected mice

    Energy Technology Data Exchange (ETDEWEB)

    Marcovistz, R; Leal, E C; De Souza Matos, D C [Departamento de Immunologia, Instituto Oswaldo Cruz, Caixa Postal 926, 21045 Rio de Janeiro (Brazil); Tsiang, H [Service Rage, Istitut Pasteur, Paris (France)

    1994-08-01

    Pathogenic parental rabies virus strain CVS (challenge virus standard) and its apathogenic variant RV194-2 were shown to differ in their ability to induce interferon (IFN) and immune response of the host. After intracerebral inoculation. IFN and antibody production was higher in the RV194-2 virus-infected mice than in the CVS infection. The enhancement of 2-5A synthetase activity, an IFN-mediated enzyme marker, showed biochemical evidence that IFN is active in both apathogenic and pathogenic infections. On the other hand, spontaneous proliferation in vitro of thymocytes and splenocytes from CVS virus-infected mice was strongly inhibited in contrast to the RV194-2 infection. In the CVS infection, the thymocyte proliferation However, in the RV194-2 infection, the thymocyte proliferation was higher than of the splenocytes. These results suggest a better performance of T-cell response to the RV194-2 infection. This fact can be critical for an enhancement of antibody production in the apathogenic infection and subsequent virus clearance from the brain of RV194-2 virus-infected mice. (author) 1 fig., 3 tabs., 32 refs.

  5. Toll-Like Receptor 2 Ligation Enhances HIV-1 Replication in Activated CCR6+ CD4+ T Cells by Increasing Virus Entry and Establishing a More Permissive Environment to Infection.

    Science.gov (United States)

    Bolduc, Jean-François; Ouellet, Michel; Hany, Laurent; Tremblay, Michel J

    2017-02-15

    In this study, we investigated the effect of Toll-like receptor 2 (TLR2) ligation on the permissiveness of activated CD4 + T cells to HIV-1 infection by focusing our experiments on the relative susceptibility of cell subsets based on their expression of CCR6. Purified primary human CD4 + T cells were first subjected to a CD3/CD28 costimulation before treatment with the TLR2 agonist Pam3CSK4. Finally, cells were inoculated with R5-tropic HIV-1 particles that permit us to study the effect of TLR2 triggering on virus production at both population and single-cell levels. We report here that HIV-1 replication is augmented in CD3/CD28-costimulated CCR6 + CD4 + T cells upon engagement of the cell surface TLR2. Additional studies indicate that a higher virus entry and polymerization of the cortical actin are seen in this cell subset following TLR2 stimulation. A TLR2-mediated increase in the level of phosphorylated NF-κB p65 subunit was also detected in CD3/CD28-costimulated CCR6 + CD4 + T cells. We propose that, upon antigenic presentation, an engagement of TLR2 acts specifically on CCR6 + CD4 + T cells by promoting virus entry in an intracellular milieu more favorable for productive HIV-1 infection. Following primary infection, HIV-1 induces an immunological and structural disruption of the gut mucosa, leading to bacterial translocation and release of microbial components in the bloodstream. These pathogen-derived constituents include several agonists of Toll-like receptors that may affect gut-homing CD4 + T cells, such as those expressing the chemokine receptor CCR6, which are highly permissive to HIV-1 infection. We demonstrate that TLR2 ligation in CD3/CD28-costimulated CCR6 + CD4 + T cells leads to enhanced virus production. Our results highlight the potential impact of bacterial translocation on the overall permissiveness of CCR6 + CD4 + T cells to productive HIV-1 infection. Copyright © 2017 American Society for Microbiology.

  6. Respiratory syncytial virus infection in sheep bronchial explants is associated with enhanced ETB receptor-mediate contractile functional and autoradiographic studies

    International Nuclear Information System (INIS)

    Fernandes, L.B.; D'Aprile, A.C.; Betts, R.J.; Goldie, R.G.

    2001-01-01

    Full text: Respiratory syncytial virus (RSV) is an important precipitant of asthma in children. The impact of RSV infection on endothelin (ET) receptor density and function in airways is unknown. In the present study, sheep bronchial rings were maintained as explants in culture for up to 48 h. During this time, both the structural integrity of the epithelium and carbachol responsiveness were preserved. Bronchial rings in culture were exposed to non-infected culture medium or to RSV (1/50 TCID 50 ) for 0, 24 and 48 h which caused marked damage to and loss of the epithelium. RSV infection did not significantly alter responsiveness to ET-1 at either 24 (Control EC 40 = 102 nM, 95% confidence limits, 76-138 nM vs RSV EC 40 = 66 nM, 95% confidence limits, 48-91 nM, n=5-6, P>0.05) or 48 h (Control EC 40 35 nM, 95% confidence limits, 19-66 nM vs RSV EC 40 = 55 nM, 95% confidence limits, 32-93 nM, n=8, P>0.05). As seen previously (Goldie et al., 1994), sarafotoxin S6c (StxS6c, ET B -selective) did not cause contraction in non-infected sheep bronchial explants. In contrast, StxS6c (300 nM) increased tone by 8±3% carbachol Emax (n=6-8) in explants exposed to RSV for 24 or 48 h. Light microscopic autoradiography was used to determine the relative distribution of ET A and ET B receptors using [ 125 I]-ET-1, BQ-123 (ET A -selective) and StxS6c. Sheep airway smooth muscle contains a homogeneous population of ET A receptors (Goldie et al., 1994). Since StxS6c caused significant contraction in RSV-infected bronchial explants, it was surprising that autoradiographic techniques failed to detect airway smooth muscle ET B receptors in these preparations. It is likely that ET B receptors fell below the level of detection of autoradiography. The significant StxS6c-induced contraction of sheep bronchi suggests the novel expression of ET B receptors triggered by RSV which might be relevant to RSV-associated asthma. Copyright (2001) Australasian Society of Clinical and Experimental

  7. Schmallenberg virus experimental infection of sheep

    DEFF Research Database (Denmark)

    Wernike, Kerstin; Hoffmann, Bernd; Bréard, Emmanuel

    2013-01-01

    production and diarrhoea for a few days. However, the knowledge about clinical signs and pathogenesis in adult sheep is limited.In the present study, adult sheep of European domestic breeds were inoculated with SBV either as cell culture grown virus or as virus with no history of passage in cell cultures...... 3–5 days by real-time RT-PCR. In total, 13 out of 30 inoculated sheep became RNAemic, with the highest viral load in animals inoculated with virus from low cell culture passaged or the animal passaged material. Contact animals remained negative throughout the study. One RNAemic sheep showed...... results in subclinical infection, transient RNAemia and a specific antibody response. Maintenance of viral RNA in the lymphoreticular system is observed for an extended period....

  8. Human papilloma virus infection and psoriasis: Did human papilloma virus infection trigger psoriasis?

    Science.gov (United States)

    Jain, Sonia P; Gulhane, Sachin; Pandey, Neha; Bisne, Esha

    2015-01-01

    Psoriasis is an autoimmune chronic inflammatory skin disease known to be triggered by streptococcal and HIV infections. However, human papilloma virus infection (HPV) as a triggering factor for the development of psoriasis has not been reported yet. We, hereby report a case of plaque type with inverse psoriasis which probably could have been triggered by genital warts (HPV infection) and discuss the possible pathomechanisms for their coexistence and its management.

  9. Multiple roles of the coagulation protease cascade during virus infection.

    Science.gov (United States)

    Antoniak, Silvio; Mackman, Nigel

    2014-04-24

    The coagulation cascade is activated during viral infections. This response may be part of the host defense system to limit spread of the pathogen. However, excessive activation of the coagulation cascade can be deleterious. In fact, inhibition of the tissue factor/factor VIIa complex reduced mortality in a monkey model of Ebola hemorrhagic fever. Other studies showed that incorporation of tissue factor into the envelope of herpes simplex virus increases infection of endothelial cells and mice. Furthermore, binding of factor X to adenovirus serotype 5 enhances infection of hepatocytes but also increases the activation of the innate immune response to the virus. Coagulation proteases activate protease-activated receptors (PARs). Interestingly, we and others found that PAR1 and PAR2 modulate the immune response to viral infection. For instance, PAR1 positively regulates TLR3-dependent expression of the antiviral protein interferon β, whereas PAR2 negatively regulates expression during coxsackievirus group B infection. These studies indicate that the coagulation cascade plays multiple roles during viral infections.

  10. Immune barriers of Ebola virus infection.

    Science.gov (United States)

    McElroy, Anita K; Mühlberger, Elke; Muñoz-Fontela, César

    2018-02-01

    Since its initial emergence in 1976 in northern Democratic Republic of Congo (DRC), Ebola virus (EBOV) has been a global health concern due to its virulence in humans, the mystery surrounding the identity of its host reservoir and the unpredictable nature of Ebola virus disease (EVD) outbreaks. Early after the first clinical descriptions of a disease resembling a 'septic-shock-like syndrome', with coagulation abnormalities and multi-system organ failure, researchers began to evaluate the role of the host immune response in EVD pathophysiology. In this review, we summarize how data gathered during the last 40 years in the laboratory as well as in the field have provided insight into EBOV immunity. From molecular mechanisms involved in EBOV recognition in infected cells, to antigen processing and adaptive immune responses, we discuss current knowledge on the main immune barriers of infection as well as outstanding research questions. Copyright © 2018 Elsevier B.V. All rights reserved.

  11. Pharmacological intervention for dengue virus infection.

    Science.gov (United States)

    Lai, Jenn-Haung; Lin, Yi-Ling; Hsieh, Shie-Liang

    2017-04-01

    Dengue virus (DENV) infection has a considerable health impact in tropical and subtropical countries worldwide. Escalation of infection rates greatly increases morbidity and mortality, most commonly from deaths due to dengue hemorrhagic fever and dengue shock syndrome. Although the development of an effective, long-lasting vaccine has been a major aim for control and prevention of DENV infection, the currently licensed vaccine has limitations and is less than satisfactory. Thus, there remains an important need to identify effective and tolerable medications for treatment of DENV-infected patients both in the early phase, to prevent progression to fatal outcomes, and to minimize deaths after patients develop severe complications. This review will address several specific points, including (1) approaches to identify anti-DENV medications, (2) recent advances in the development of potential compounds targeting DENV infection, (3) experience with clinical trials of regimens for DENV infection, (4) some available medications of potential for clinical trials against DENV infection, (5) reasons for unsuccessful outcomes and challenges of anti-DENV treatments, and (6) directions for developing or selecting better anti-DENV strategies. This review provides useful guidance for clinicians selecting drugs for DENV-infected patients with severe manifestations or potential fatal disease progression, and for basic researchers seeking to develop effective anti-DENV regimens. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Clinical and biological differences between recurrent herpes simplex virus and varicella-zoster virus infections

    International Nuclear Information System (INIS)

    Straus, S.E.

    1989-01-01

    The major features that distinguish recurrent herpes simplex virus infections from zoster are illustrated in this article by two case histories. The clinical and epidemiologic features that characterize recurrent herpes simplex virus and varicella-zoster virus infections are reviewed. It is noted that herpesvirus infections are more common and severe in patients with cellular immune deficiency. Each virus evokes both humoral and cellular immune response in the course of primary infection. DNA hybridization studies with RNA probes labelled with sulfur-35 indicate that herpes simplex viruses persist within neurons, and that varicella-zoster virus is found in the satellite cells that encircle the neurons

  13. Mechanisms of Zika Virus Infection and Neuropathogenesis.

    Science.gov (United States)

    Olagnier, David; Muscolini, Michela; Coyne, Carolyn B; Diamond, Michael S; Hiscott, John

    2016-08-01

    A spotlight has been focused on the mosquito-borne Zika virus (ZIKV) because of its epidemic outbreak in Brazil and Latin America, as well as the severe neurological manifestations of microcephaly and Guillain-Barré syndrome associated with infection. In this review, we discuss the recent literature on ZIKV-host interactions, including new mechanistic insight concerning the basis of ZIKV-induced neuropathogenesis.

  14. Visualization of the African swine fever virus infection in living cells by incorporation into the virus particle of green fluorescent protein-p54 membrane protein chimera

    International Nuclear Information System (INIS)

    Hernaez, Bruno; Escribano, Jose M.; Alonso, Covadonga

    2006-01-01

    Many stages of African swine fever virus infection have not yet been studied in detail. To track the behavior of African swine fever virus (ASFV) in the infected cells in real time, we produced an infectious recombinant ASFV (B54GFP-2) that expresses and incorporates into the virus particle a chimera of the p54 envelope protein fused to the enhanced green fluorescent protein (EGFP). The incorporation of the fusion protein into the virus particle was confirmed immunologically and it was determined that p54-EGFP was fully functional by confirmation that the recombinant virus made normal-sized plaques and presented similar growth curves to the wild-type virus. The tagged virus was visualized as individual fluorescent particles during the first stages of infection and allowed to visualize the infection progression in living cells through the viral life cycle by confocal microscopy. In this work, diverse potential applications of B54GFP-2 to study different aspects of ASFV infection are shown. By using this recombinant virus it was possible to determine the trajectory and speed of intracellular virus movement. Additionally, we have been able to visualize for first time the ASFV factory formation dynamics and the cytophatic effect of the virus in live infected cells. Finally, we have analyzed virus progression along the infection cycle and infected cell death as time-lapse animations

  15. Outbreaks of Tilapia Lake Virus Infection, Thailand, 2015-2016.

    Science.gov (United States)

    Surachetpong, Win; Janetanakit, Taveesak; Nonthabenjawan, Nutthawan; Tattiyapong, Puntanat; Sirikanchana, Kwanrawee; Amonsin, Alongkorn

    2017-06-01

    During 2015-2016, several outbreaks of tilapia lake virus infection occurred among tilapia in Thailand. Phylogenetic analysis showed that the virus from Thailand grouped with a tilapia virus (family Orthomyxoviridae) from Israel. This emerging virus is a threat to tilapia aquaculture in Asia and worldwide.

  16. Outbreaks of Tilapia Lake Virus Infection, Thailand, 2015?2016

    OpenAIRE

    Surachetpong, Win; Janetanakit, Taveesak; Nonthabenjawan, Nutthawan; Tattiyapong, Puntanat; Sirikanchana, Kwanrawee; Amonsin, Alongkorn

    2017-01-01

    During 2015?2016, several outbreaks of tilapia lake virus infection occurred among tilapia in Thailand. Phylogenetic analysis showed that the virus from Thailand grouped with a tilapia virus (family Orthomyxoviridae) from Israel. This emerging virus is a threat to tilapia aquaculture in Asia and worldwide.

  17. Photodynamic treatment of Herpes simplex virus infection in vitro

    International Nuclear Information System (INIS)

    Lytle, C.D.; Hester, L.D.

    1976-01-01

    The effects of photodynamic action on in vitro herpes simplex virus infections of CV-1 monkey kidney fibroblasts or human skin fibroblasts were determined using proflavine sulfate and white fluorescent lamps. Photodynamic treatment of confluent cell monolayers prior to virus infection inactivated cell capacity, i.e. the capacity of the treated cells to support subsequent virus growth as measured by plaque formation. The capacity of human cells was more sensitive to inactivation than the capacity of monkey cells when 6 μM proflavine was used. Treated cell monolayers recovered the capacity to support virus plaque formation when virus infection was delayed four days after the treatment. Experiments in which the photodynamically treated monolayers were infected with UV-irradiated virus demonstrated that this treatment induced Weigle reactivation in both types of cells. This reactivation occurred for virus infection just after treatment or 4 days later. A Luria-Latarjet-type experiment was also performed in which cultures infected with unirradiated virus were photodynamically treated at different times after the start of infection. The results showed that for the first several hours of the virus infection the infected cultures were more sensitive to inactivation by photodynamic treatment than cell capacity. By the end of the eclipse period the infected cultures were less sensitive to inactivation than cell capacity. Results from extracellular inactivation of virus growth in monkey cells at 6 μM proflavine indicated that at physiological pH the virus has a sensitivity to photodynamic inactivation similar to that for inactivation of cell capacity. The combined data indicated that photodynamic treatment of the cell before or after virus infection could prevent virus growth. Thus, photodynamic inactivation of infected and uninfected cells may be as important as inactivation of virus particles when considering possible mechanisms in clinical photodynamic therapy for herpes

  18. TIM-family proteins promote infection of multiple enveloped viruses through virion-associated phosphatidylserine.

    Directory of Open Access Journals (Sweden)

    Stephanie Jemielity

    2013-03-01

    Full Text Available Human T-cell Immunoglobulin and Mucin-domain containing proteins (TIM1, 3, and 4 specifically bind phosphatidylserine (PS. TIM1 has been proposed to serve as a cellular receptor for hepatitis A virus and Ebola virus and as an entry factor for dengue virus. Here we show that TIM1 promotes infection of retroviruses and virus-like particles (VLPs pseudotyped with a range of viral entry proteins, in particular those from the filovirus, flavivirus, New World arenavirus and alphavirus families. TIM1 also robustly enhanced the infection of replication-competent viruses from the same families, including dengue, Tacaribe, Sindbis and Ross River viruses. All interactions between TIM1 and pseudoviruses or VLPs were PS-mediated, as demonstrated with liposome blocking and TIM1 mutagenesis experiments. In addition, other PS-binding proteins, such as Axl and TIM4, promoted infection similarly to TIM1. Finally, the blocking of PS receptors on macrophages inhibited the entry of Ebola VLPs, suggesting that PS receptors can contribute to infection in physiologically relevant cells. Notably, infection mediated by the entry proteins of Lassa fever virus, influenza A virus and SARS coronavirus was largely unaffected by TIM1 expression. Taken together our data show that TIM1 and related PS-binding proteins promote infection of diverse families of enveloped viruses, and may therefore be useful targets for broad-spectrum antiviral therapies.

  19. Hepatitis A virus infection - shifting epidemiology

    International Nuclear Information System (INIS)

    Tariq, W.Z.; Hussain, A.B.; Hussain, T.; Anwar, M.; Ghani, E.; Asad-Ullah

    2006-01-01

    Objective of the Study: To determine the age distribution in HAV infection and seasonal variations in the prevalence of acute viral hepatitis caused by hepatitis A virus. Study Design: A descriptive study. Place and Duration: The study was carried out on the patients reporting at Virology Department, Armed Forces Institute of Pathology (AFIP), Rawalpindi, for determination of hepatitis A virus (HAV) IgM antibody, from July 2003 to June 2004. Patients and Methods: Altogether 626 patients with clinical suspicion of hepatitis A virus infection were referred to AFIP Rawalpindi for this test. Blood samples were collected and sera were separated and transferred to plastic aliquots that were stored at -20 deg. C in a retrievable fashion until utilized in testing. The testing for ant-HAY IgM was carried out with the help of a commercial Enzyme Linked Immunosorbent Assay (ELISA) using reagent kits of Dias Orin (Germany) for HAV IgM antibodies. Results: The HAV IgM positive rate was 40.57% (252/626). Those tested included the sporadic cases as well as the patients from outbreak in two schools of Nowshera cantonment. The age of patients testing positive for HAV IgM, ranged from 03 to 27 years. There was a statistically significant seasonal difference in rate of positivity in different months of the calendar year. An outbreak of HAV infection was seen in the children of two neighboring schools of a cantonment, in which 44 children in different classes developed clinical jaundice. Conclusion: HAV infection occurs in a significant proportion of young people with a clinical suspicion of HAV infection. There is a changing trend of developing hepatitis a in the age beyond 18 years and in outbreaks, which was not there in our patients previously due to universal immunity found against HAV by the age of 18. It was because of chances of consumption of polluted food. (author)

  20. Laboratory Diagnosis of Zika Virus Infection.

    Science.gov (United States)

    Landry, Marie Louise; St George, Kirsten

    2017-01-01

    -The rapid and accurate diagnosis of Zika virus infection is an international priority. -To review current recommendations, methods, limitations, and priorities for Zika virus testing. -Sources include published literature, public health recommendations, laboratory procedures, and testing experience. -Until recently, the laboratory diagnosis of Zika infection was confined to public health or research laboratories that prepared their own reagents, and test capacity has been limited. Furthermore, Zika cross-reacts serologically with other flaviviruses, such as dengue, West Nile, and yellow fever. Current or past infection, or even vaccination with another flavivirus, will often cause false-positive or uninterpretable Zika serology results. Detection of viral RNA during acute infection using nucleic acid amplification tests provides more specific results, and a number of commercial nucleic acid amplification tests have received emergency use authorization. In addition to serum, testing of whole blood and urine is recommended because of the higher vial loads and longer duration of shedding. However, nucleic acid amplification testing has limited utility because many patients are asymptomatic or present for testing after the brief period of Zika shedding has passed. Thus, the greatest need and most difficult challenge is development of accurate antibody tests for the diagnosis of recent Zika infection. Research is urgently needed to identify Zika virus epitopes that do not cross-react with other flavivirus antigens. New information is emerging at a rapid pace and, with ongoing public-private and international collaborations and government support, it is hoped that rapid progress will be made in developing robust and widely applicable diagnostic tools.

  1. MAIT cells are activated in acute Dengue virus infection and after in vitro Zika virus infection.

    Directory of Open Access Journals (Sweden)

    Dominic Paquin-Proulx

    2018-01-01

    Full Text Available Dengue virus (DENV and Zika virus (ZIKV are members of the Flaviviridae and are predominantly transmitted via mosquito bites. Both viruses are responsible for a growing number of infections in tropical and subtropical regions. DENV infection can cause lethargy with severe morbidity and dengue shock syndrome leading to death in some cases. ZIKV is now linked with Guillain-Barré syndrome and fetal malformations including microcephaly and developmental disorders (congenital Zika syndrome. The protective and pathogenic roles played by the immune response in these infections is unknown. Mucosal-associated invariant T (MAIT cells are a population of innate T cells with potent anti-bacterial activity. MAIT cells have also been postulated to play a role in the immune response to viral infections. In this study, we evaluated MAIT cell frequency, phenotype, and function in samples from subjects with acute and convalescent DENV infection. We found that in acute DENV infection, MAIT cells had elevated co-expression of the activation markers CD38 and HLA-DR and had a poor IFNγ response following bacterial stimulation. Furthermore, we found that MAIT cells can produce IFNγ in response to in vitro infection with ZIKV. This MAIT cell response was independent of MR1, but dependent on IL-12 and IL-18. Our results suggest that MAIT cells may play an important role in the immune response to Flavivirus infections.

  2. Hepatitis E Virus (HEV) Infection in Ireland

    LENUS (Irish Health Repository)

    Hickey, C

    2016-09-01

    Hepatitis E virus (HEV) is a single stranded RNA virus causing infection worldwide. In developing countries HEV genotypes 1 and 2 spread faeco-orally via water. Recently, infections with HEV have been detected in Europe and North America in patients with no travel history. These are food-borne HEV genotypes 3 and 4, a pig-associated zoonosis. Most infections are asymptomatic but morbidity and chronic infection may occur with prior liver disease or immunosuppression. International seroprevalence rates vary and with improved diagnostics have increased. To determine the current prevalence in this region we studied anonymised serum samples submitted in 2015 for routine testing. We detected anti-HEV IgG in 16\\/198 (8%) individuals, highest rate in 40-59 year olds (43.8%). This is higher than reported for the same region in 1995 (0.4%) using a previous generation assay. This study provides evidence of HEV circulation in Ireland and reinforces the need for ongoing surveillance.

  3. Viral protein synthesis in cowpea mosaic virus infected protoplasts

    International Nuclear Information System (INIS)

    Rottier, P.

    1980-01-01

    Some aspects of cowpea mosaic virus (CPMV) multiplication in cowpea mesophyll protoplasts were studied. The detection and characterization of proteins whose synthesis is induced or is stimulated upon virus infection was performed with the aid of radioactive labelling. (Auth.)

  4. Stability of RNA silencing-based traits after virus infection

    DEFF Research Database (Denmark)

    Jørgensen, Bodil; Albrechtsen, Merete

    2007-01-01

    with constructs based on virus coat protein (CP) genes or other viral genes has been successfully used to engineer PTGS-mediated virus resistance into a large number of crop plants and some transgenic lines have been commercially exploited. However the discovery that plant viruses encode suppressors of gene...... silencing has raised concerns that virus infection of crop plants might reverse the new silencing-based traits. Most studies of virus suppression of silencing have used model systems based on silencing of reporter genes. A few studies have analysed the effects of virus infections on plants with genetically...... engineered virus resistance based on either a simple sense or an inverted repeat construct. We decided to use genetically engineered virus resistance in potato as a model system for further studies of the effect of virus infection on genetically engineered traits. We present for the first time a comparison...

  5. Mechanisms of immune evasion in Epstein-Barr virus infection

    NARCIS (Netherlands)

    Gram., A.M.

    2016-01-01

    The human herpesvirus Epstein-Barr virus (EBV) is a large DNA virus that infects over 90% of the adult world population. EBV is the causative agent of infectious mononucleosis and EBV infection is associated with various malignancies. EBV establishes lifelong infections in immunocompetent hosts. To

  6. Clinical studies on hepatitis B, C, and E virus infection

    NARCIS (Netherlands)

    Willemse, S.B.

    2017-01-01

    Chronic viral hepatitis is a major cause of liver-related morbidity and mortality. This thesis describes clinical aspects of hepatitis B, C, and E virus infection. Part I focuses on hepatitis B virus (HBV) infection. This part describes immune responses of patients with acute HBV-infection,

  7. Post-infection immunodeficiency virus control by neutralizing antibodies.

    Directory of Open Access Journals (Sweden)

    Hiroyuki Yamamoto

    Full Text Available BACKGROUND: Unlike most acute viral infections controlled with the appearance of virus-specific neutralizing antibodies (NAbs, primary HIV infections are not met with such potent and early antibody responses. This brings into question if or how the presence of potent antibodies can contribute to primary HIV control, but protective efficacies of antiviral antibodies in primary HIV infections have remained elusive; and, it has been speculated that even NAb induction could have only a limited suppressive effect on primary HIV replication once infection is established. Here, in an attempt to answer this question, we examined the effect of passive NAb immunization post-infection on primary viral replication in a macaque AIDS model. METHODS AND FINDINGS: The inoculums for passive immunization with simian immunodeficiency virus mac239 (SIVmac239-specific neutralizing activity were prepared by purifying polyclonal immunoglobulin G from pooled plasma of six SIVmac239-infected rhesus macaques with NAb induction in the chronic phase. Passive immunization of rhesus macaques with the NAbs at day 7 after SIVmac239 challenge resulted in significant reduction of set-point plasma viral loads and preservation of central memory CD4 T lymphocyte counts, despite the limited detection period of the administered NAb responses. Peripheral lymph node dendritic cell (DC-associated viral RNA loads showed a remarkable peak with the NAb administration, and DCs stimulated in vitro with NAb-preincubated SIV activated virus-specific CD4 T lymphocytes in an Fc-dependent manner, implying antibody-mediated virion uptake by DCs and enhanced T cell priming. CONCLUSIONS: Our results present evidence indicating that potent antibody induction post-infection can result in primary immunodeficiency virus control and suggest direct and indirect contribution of its absence to initial control failure in HIV infections. Although difficulty in achieving requisite neutralizing titers for

  8. La Crosse virus infection alters blood feeding behavior in Aedes triseriatus and Aedes albopictus (Diptera: Culicidae).

    Science.gov (United States)

    Jackson, Bryan T; Brewster, Carlyle C; Paulson, Sally L

    2012-11-01

    The effects of La Crosse virus (LACV) infection on blood feeding behavior in Aedes triseriatus (Say) and Aedes albopictus (Skuse) were investigated in the laboratory by measuring the size of the bloodmeal imbibed and the extent of refeeding by virus-infected and uninfected mosquitoes. LACV-infected Ae. triseriatus and Ae. albopictus took significantly less blood compared with uninfected mosquitoes. Twice as many virus-infected Ae. triseriatus mosquitoes refed compared with uninfected individuals (18 vs. 9%; P < 0.05); however, virus infection had no significant effect on the refeeding rate of Ae. albopictus. Reduction in bloodmeal size followed by an increased avidity for refeeding may lead to enhanced horizontal transmission of the LACV by its principal vector, Ae. triseriatus.

  9. Ebola virus (EBOV) infection: Therapeutic strategies.

    Science.gov (United States)

    De Clercq, Erik

    2015-01-01

    Within less than a year after its epidemic started (in December 2013) in Guinea, Ebola virus (EBOV), a member of the filoviridae, has spread over a number of West-African countries (Guinea, Sierra Leone and Liberia) and gained allures that have been unprecedented except by human immunodeficiency virus (HIV). Although EBOV is highly contagious and transmitted by direct contact with body fluids, it could be counteracted by the adequate chemoprophylactic and -therapeutic interventions: vaccines, antibodies, siRNAs (small interfering RNAs), interferons and chemical substances, i.e. neplanocin A derivatives (i.e. 3-deazaneplanocin A), BCX4430, favipiravir (T-705), endoplasmic reticulum (ER) α-glucosidase inhibitors and a variety of compounds that have been found to inhibit EBOV infection blocking viral entry or by a mode of action that still has to be resolved. Much has to be learned from the mechanism of action of the compounds active against VSV (vesicular stomatitis virus), a virus belonging to the rhabdoviridae, that in its mode of replication could be exemplary for the replication of filoviridae. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Comparison of association of diabetes mellitus in hepatitis C virus infection and hepatitis B virus infection

    International Nuclear Information System (INIS)

    Khan, I.A.; Bukhari, M.H.; Khokhar, M.S.

    2013-01-01

    Background: While patients with liver disease are known to have a higher prevalence of glucose intolerance, preliminary studies suggest that hepatitis C virus (HCV) infection may be an additional risk factor for the development of diabetes mellitus (DM). Objective: The presented study was aimed to study and determine a relationship between the relative proportions of Diabetes Mellitus in patients suffering from HCV infection. Study Design: This cross sectional study. Study Settings: Patients were registered from outdoor as well as indoor departments of different teaching hospitals (Services hospital Lahore and medical departments in Jinnah hospital, Mayo hospital, Sir Ganga Ram hospital) in Lahore, Pakistan. Methods: This cross sectional study was comprised of age and sex matched 258 patients of viral hepatitis B infection and viral hepatitis C infection, conducted at Hepatitis Clinic Services Hospital, affiliated with Post Graduate Medical Institute, Lahore. Diagnosis of HBV was made with evidence of hepatitis B surface antigen, HCV infection was diagnosed if patient was sero positive for anti HCV (ELISA methods) and HCV - RNA (By PCR). Diabetes Mellitus was diagnosed after fulfilling the American Diabetic Association Criteria, from November, 2000 to September, 2002. Results: A total of 318 patients were registered, out of which 258 cases fulfilled the inclusion criteria, 164 hepatitis C infected and 94 hepatitis B infected cases, 16.46% hepatitis C infected cases were diagnosed as diabetics while 4.25% hepatitis B infected cases were diagnosed as diabetics. Conclusion: This study concludes that there is high Association and relationship of Diabetes Mellitus with Hepatitis C virus infection as compared with Hepatitis B virus infection. (author)

  11. Zika virus infection: a public health emergency!

    OpenAIRE

    Qureshi, Muhammad Salman Haider; Qureshi, Bakhtawar Wajeeha; Khan, Ramsha

    2017-01-01

    Zika virus belongs to the family of Flaviviridae. The Flaviviridae family also includes other human pathogens like West Nile virus (WNV), Yellow fever virus (YFV), mosquito transmitted Dengue virus (DENV), Tick borne encephalitic virus (TBEV) and Japanese encephalitis virus (JEV). Zika virus is a mosquito-borne disease and is transmitted by Aedes aegypti mosquito.

  12. Chronic Active Epstein–Barr Virus Infection

    Directory of Open Access Journals (Sweden)

    Li Jun

    2012-06-01

    Full Text Available Chronic active Epstein-Barr virus (CAEBV infection is a systemic Epstein-Barr virus (EBV positive lymphoprolifetative disease characterized by fever, lymphadenopathy, splenomegaly, unusual pattern of anti- EBV antibodies, and/or increased EBV genomes in affected tissues. Most cases are from Asia. So far, there is hardly any adult case reported from mainland of China. We herein presented a 33-year-old man with fever, facial erythema and rash, lymphadenopathy, lower limbs weakness, splenomegaly and liver lesion. EBV VCA, EA and EBNA were all positive. EBV DNA could be found in serum and PBMC. In situ hybridization of EBV encoded RNA in skin and liver biopsy was positive. Viral load in serum decreased under interferon alpha therapy. To our knowledge, it’s the first adult case reported from mainland of China.

  13. Congenital Zika Virus Infection: Beyond Neonatal Microcephaly.

    Science.gov (United States)

    Melo, Adriana Suely de Oliveira; Aguiar, Renato Santana; Amorim, Melania Maria Ramos; Arruda, Monica B; Melo, Fabiana de Oliveira; Ribeiro, Suelem Taís Clementino; Batista, Alba Gean Medeiros; Ferreira, Thales; Dos Santos, Mayra Pereira; Sampaio, Virgínia Vilar; Moura, Sarah Rogéria Martins; Rabello, Luciana Portela; Gonzaga, Clarissa Emanuelle; Malinger, Gustavo; Ximenes, Renato; de Oliveira-Szejnfeld, Patricia Soares; Tovar-Moll, Fernanda; Chimelli, Leila; Silveira, Paola Paz; Delvechio, Rodrigo; Higa, Luiza; Campanati, Loraine; Nogueira, Rita M R; Filippis, Ana Maria Bispo; Szejnfeld, Jacob; Voloch, Carolina Moreira; Ferreira, Orlando C; Brindeiro, Rodrigo M; Tanuri, Amilcar

    2016-12-01

    Recent studies have reported an increase in the number of fetuses and neonates with microcephaly whose mothers were infected with the Zika virus (ZIKV) during pregnancy. To our knowledge, most reports to date have focused on select aspects of the maternal or fetal infection and fetal effects. To describe the prenatal evolution and perinatal outcomes of 11 neonates who had developmental abnormalities and neurological damage associated with ZIKV infection in Brazil. We observed 11 infants with congenital ZIKV infection from gestation to 6 months in the state of Paraíba, Brazil. Ten of 11 women included in this study presented with symptoms of ZIKV infection during the first half of pregnancy, and all 11 had laboratory evidence of the infection in several tissues by serology or polymerase chain reaction. Brain damage was confirmed through intrauterine ultrasonography and was complemented by magnetic resonance imaging. Histopathological analysis was performed on the placenta and brain tissue from infants who died. The ZIKV genome was investigated in several tissues and sequenced for further phylogenetic analysis. Description of the major lesions caused by ZIKV congenital infection. Of the 11 infants, 7 (63.6%) were female, and the median (SD) maternal age at delivery was 25 (6) years. Three of 11 neonates died, giving a perinatal mortality rate of 27.3%. The median (SD) cephalic perimeter at birth was 31 (3) cm, a value lower than the limit to consider a microcephaly case. In all patients, neurological impairments were identified, including microcephaly, a reduction in cerebral volume, ventriculomegaly, cerebellar hypoplasia, lissencephaly with hydrocephalus, and fetal akinesia deformation sequence (ie, arthrogryposis). Results of limited testing for other causes of microcephaly, such as genetic disorders and viral and bacterial infections, were negative, and the ZIKV genome was found in both maternal and neonatal tissues (eg, amniotic fluid, cord blood, placenta, and

  14. Photodynamic inactivation of rubella virus enhances recombination with a latent virus of a baby hamster kidney cell line BHK21

    International Nuclear Information System (INIS)

    Yamamoto, Nobuto; Urade, Masahiro

    1989-01-01

    Rubella virus is very sensitive to photodynamic action. When tested with 1.2 x 10 -5 M toluidine blue and 8 W fluorescent lamp at a fluence of 11 W/m 2 , inactivation kinetics showed a linear single hit curve with a k value of 1.48 min -1 . Photodynamic inactivation of rubella virus greatly enhanced recombination with a latent virus (R-virus) of baby hamster kidney BHK21 cells. In contrast, no hybrids were detected in lysates of the cells infected with either UV-treated or untreated rubella virus. Therefore, hybrid viruses were readily detected only in lysates of BHK21 cells infected with photodynamically treated rubella virus. Photodynamic damage of rubella virus genomes generated a new hybrid type (hybrid type 3) in addition to a previously described type 2 hybrid (formerly designated as HPV-RV variant). Although both of these hybrid types carry the CF antigens of rubella virus, plaque forming ability of type 3 hybrid is neutralized neither by anti-rubella serum nor by anti-latent virus serum while type 2 hybrid is neutralized by anti-latent virus serum. (author)

  15. Additive interactions of unrelated viruses in mixed infections of cowpea.

    Directory of Open Access Journals (Sweden)

    Imade Yolanda Nsa

    2015-10-01

    Full Text Available This study was carried out to determine the effects of single infections and co-infections of three unrelated viruses on three cowpea cultivars (one commercial cowpea cultivar White and 2 IITA lines; IT81D-985 and TVu76. The plants were inoculated with Cowpea aphid-borne mosaic virus (CABMV, genus Potyvirus, Cowpea mottle virus (CMeV, genus Carmovirus and Southern bean mosaic virus (SBMV, genus Sobemovirus singly and in mixture (double and triple at 10, 20 and 30 days after planting (DAP. The treated plants were assessed for susceptibility to the viruses, growth and yield. In all cases of infection, early inoculation resulted in higher disease severity compared with late infection. The virus treated cowpea plants were relatively shorter than buffer inoculated control plants except the IT81D-985 plants that were taller and produced more foliage. Single infections by CABMV, CMeV and SBMV led to a complete loss of seeds in the three cowpea cultivars at 10DAP; only cultivar White produced some seeds at 30DAP. Double and triple virus infections led to a total loss of seeds in all three cowpea cultivars. None of the virus infected IITA lines produced any seeds except IT81D-985 plants co-infected with CABMV and SBMV at 30DAP with a reduction of 80%. Overall, the commercial cultivar White was the least susceptible to the virus treatments and produced the most yield (flowers, pods and seeds. CABMV was the most aggressive of these viruses and early single inoculations with this virus resulted in the premature death of some of the seedlings. The presence of the Potyvirus, CABMV in the double virus infections did not appear to increase disease severity or yield loss. There was no strong evidence for synergistic interactions between the viruses in the double virus mixtures.

  16. Lack of Durable Cross-Neutralizing Antibodies Against Zika Virus from Dengue Virus Infection.

    Science.gov (United States)

    Collins, Matthew H; McGowan, Eileen; Jadi, Ramesh; Young, Ellen; Lopez, Cesar A; Baric, Ralph S; Lazear, Helen M; de Silva, Aravinda M

    2017-05-01

    Cross-reactive antibodies elicited by dengue virus (DENV) infection might affect Zika virus infection and confound serologic tests. Recent data demonstrate neutralization of Zika virus by monoclonal antibodies or human serum collected early after DENV infection. Whether this finding is true in late DENV convalescence (>6 months after infection) is unknown. We studied late convalescent serum samples from persons with prior DENV or Zika virus exposure. Despite extensive cross-reactivity in IgG binding, Zika virus neutralization was not observed among primary DENV infections. We observed low-frequency (23%) Zika virus cross-neutralization in repeat DENV infections. DENV-immune persons who had Zika virus as a secondary infection had distinct populations of antibodies that neutralized DENVs and Zika virus, as shown by DENV-reactive antibody depletion experiments. These data suggest that most DENV infections do not induce durable, high-level Zika virus cross-neutralizing antibodies. Zika virus-specific antibody populations develop after Zika virus infection irrespective of prior DENV immunity.

  17. Autophagic flux without a block differentiates varicella-zoster virus infection from herpes simplex virus infection.

    Science.gov (United States)

    Buckingham, Erin M; Carpenter, John E; Jackson, Wallen; Zerboni, Leigh; Arvin, Ann M; Grose, Charles

    2015-01-06

    Autophagy is a process by which misfolded and damaged proteins are sequestered into autophagosomes, before degradation in and recycling from lysosomes. We have extensively studied the role of autophagy in varicella-zoster virus (VZV) infection, and have observed that vesicular cells are filled with >100 autophagosomes that are easily detectable after immunolabeling for the LC3 protein. To confirm our hypothesis that increased autophagosome formation was not secondary to a block, we examined all conditions of VZV infection as well as carrying out two assessments of autophagic flux. We first investigated autophagy in human skin xenografts in the severe combined immunodeficiency (SCID) mouse model of VZV pathogenesis, and observed that autophagosomes were abundant in infected human skin tissues. We next investigated autophagy following infection with sonically prepared cell-free virus in cultured cells. Under these conditions, autophagy was detected in a majority of infected cells, but was much less than that seen after an infected-cell inoculum. In other words, inoculation with lower-titered cell-free virus did not reflect the level of stress to the VZV-infected cell that was seen after inoculation of human skin in the SCID mouse model or monolayers with higher-titered infected cells. Finally, we investigated VZV-induced autophagic flux by two different methods (radiolabeling proteins and a dual-colored LC3 plasmid); both showed no evidence of a block in autophagy. Overall, therefore, autophagy within a VZV-infected cell was remarkably different from autophagy within an HSV-infected cell, whose genome contains two modifiers of autophagy, ICP34.5 and US11, not present in VZV.

  18. Plant RNA binding proteins for control of RNA virus infection

    Directory of Open Access Journals (Sweden)

    Sung Un eHuh

    2013-12-01

    Full Text Available Plant RNA viruses have effective strategies to infect host plants through either direct or indirect interactions with various host proteins, thus suppressing the host immune system. When plant RNA viruses enter host cells exposed RNAs of viruses are recognized by the host immune system through processes such as siRNA-dependent silencing. Interestingly, some host RNA binding proteins have been involved in the inhibition of RNA virus replication, movement, and translation through RNA-specific binding. Host plants intensively use RNA binding proteins for defense against viral infections in nature. In this mini review, we will summarize the function of some host RNA binding proteins which act in a sequence-specific binding manner to the infecting virus RNA. It is important to understand how plants effectively suppresses RNA virus infections via RNA binding proteins, and this defense system can be potentially developed as a synthetic virus defense strategy for use in crop engineering.

  19. Neurological complications of Zika virus infection.

    Science.gov (United States)

    Carod-Artal, Francisco Javier

    2018-04-26

    Zika virus (ZIKV) disease is a vector-borne infectious disease transmitted by Aedes mosquitoes. Recently, ZIKV has caused outbreaks in most American countries. Areas covered: Publications about neurological complications of ZIKV infection retrieved from pubmed searchers were reviewed, and reference lists and relevant articles from review articles were also examined. Vertical/intrauterine transmission leads to congenital infection and causes microcephaly and congenital ZIKV syndrome. ZIKV preferentially infects human neural progenitor cells and triggers cell apoptosis. ZIKV RNA has been identified in foetal brain tissue and brains of microcephalic infants who died; amniotic fluid and placentas of pregnant mothers; and umbilical cord, cerebro-spinal fluid and meninges of newborns. The increase in the number of Guillain-Barre syndrome (GBS) cases during the ZIKV outbreak in the Americas provides epidemiological evidence for the link between ZIKV infection and GBS. Less frequently reported ZIKV neurological complications include encephalitis/meningoencephalitis, acute disseminated encephalomyelitis, myelitis, cerebrovascular complications (ischemic infarction; vasculopathy), seizures and encephalopathy, sensory polyneuropathy and sensory neuronopathy. Analysis of GBS incidence could serve as an epidemiological 'marker' or sentinel for ZIKV disease and other neurological complications associated to ZIKV. Expert commentary: An expanding spectrum of neurological complications associated with ZIKV infection is being recognised.

  20. The CD8 T Cell Response to Respiratory Virus Infections.

    Science.gov (United States)

    Schmidt, Megan E; Varga, Steven M

    2018-01-01

    Humans are highly susceptible to infection with respiratory viruses including respiratory syncytial virus (RSV), influenza virus, human metapneumovirus, rhinovirus, coronavirus, and parainfluenza virus. While some viruses simply cause symptoms of the common cold, many respiratory viruses induce severe bronchiolitis, pneumonia, and even death following infection. Despite the immense clinical burden, the majority of the most common pulmonary viruses lack long-lasting efficacious vaccines. Nearly all current vaccination strategies are designed to elicit broadly neutralizing antibodies, which prevent severe disease following a subsequent infection. However, the mucosal antibody response to many respiratory viruses is not long-lasting and declines with age. CD8 T cells are critical for mediating clearance following many acute viral infections in the lung. In addition, memory CD8 T cells are capable of providing protection against secondary infections. Therefore, the combined induction of virus-specific CD8 T cells and antibodies may provide optimal protective immunity. Herein, we review the current literature on CD8 T cell responses induced by respiratory virus infections. Additionally, we explore how this knowledge could be utilized in the development of future vaccines against respiratory viruses, with a special emphasis on RSV vaccination.

  1. Zika virus infections in pregnancy: epidemics and case management

    Directory of Open Access Journals (Sweden)

    Fatih sahiner

    2016-03-01

    Full Text Available Zika virus is an RNA virus belonging to the Flaviviridae family, and is primarily transmitted by Aedes mosquitoes. Only a small number of cases had been described until 2007 when the first major Zika virus outbreak occurred on Yap Island, Micronesia. Approximately 80% of people infected with Zika virus do not exhibit any symptoms. Symptomatic infections are generally moderate and characterized by acute onset of fever, maculopapular rash, arthralgia, or conjunctivitis. The virus has recently attracted a broad interest due to the emerging cases of microcephaly that are possibly associated with mothers infected by the Zika virus during pregnancy, and the regional increases in the incidence of Guillain-Barre syndrome during the epidemic periods. Although the relationship between Zika virus infection and these abnormalities is not obviously understood yet, Zika virus testing is recommended for infants with microcephaly or intracranial calcifications whose mothers were potentially infected with the Zika virus during pregnancy. Every day, new reports are being published about the outbreaks associated with this virus; nevertheless, no new cases of this virus have been reported in Turkey. Despite this, we cannot currently exclude the possibility of the encounter with the virus because of the presence of Aedes mosquitoes, which are responsible for the spread of the virus, are prevalent in Turkey, and an increasing number of travel-related cases are being reported from different countries. In the light of the current knowledge on this virus, this review aims to discuss the course of Zika virus infections in detail, especially congenital infection, and presenting current information about the case management and preventive measures. [Cukurova Med J 2016; 41(1.000: 143-151

  2. Norepinephrine and Epinephrine Enhanced the Infectivity of Enterovirus 71.

    Directory of Open Access Journals (Sweden)

    Yu-Ting Liao

    Full Text Available Enterovirus 71 (EV71 infections may be associated with neurological complications, including brainstem encephalitis (BE. Severe EV71 BE may be complicated with autonomic nervous system (ANS dysregulation and/or pulmonary edema (PE. ANS dysregulation is related to the overactivation of the sympathetic nervous system, which results from catecholamine release.The aims of this study were to explore the effects of catecholamines on severe EV71 infection and to investigate the changes in the percentages of EV71-infected cells, virus titer, and cytokine production on the involvement of catecholamines.Plasma levels of norepinephrine (NE and epinephrine (EP in EV71-infected patients were measured using an enzyme-linked immunoassay. The expression of adrenergic receptors (ADRs on RD, A549, SK-N-SH, THP-1, Jurkat and human peripheral blood mononuclear cells (hPBMCs were detected using flow cytometry. The percentages of EV71-infected cells, virus titer, and cytokine production were investigated after treatment with NE and EP.The plasma levels of NE and EP were significantly higher in EV71-infected patients with ANS dysregulation and PE than in controls. Both α1A- and β2-ADRs were expressed on A549, RD, SK-N-SH, HL-60, THP-1, Jurkat cells and hPBMCs. NE treatment elevated the percentages of EV71-infected cells to 62.9% and 22.7% in THP-1 and Jurkat cells, respectively. Via treatment with EP, the percentages of EV71-infected cells were increased to 64.6% and 26.9% in THP-1 and Jurkat cells. The percentage of EV71-infected cells increased upon NE or EP treatment while the α- and β-blockers reduced the percentages of EV71-infected cells with NE or EP treatment. At least two-fold increase in virus titer was observed in EV71-infected A549, SK-N-SH and hPBMCs after treatment with NE or EP. IL-6 production was enhanced in EV71-infected hPBMCs at a concentration of 102 pg/mL NE.The plasma levels of NE and EP elevated in EV71-infected patients with ANS

  3. Norepinephrine and Epinephrine Enhanced the Infectivity of Enterovirus 71.

    Science.gov (United States)

    Liao, Yu-Ting; Wang, Shih-Min; Wang, Jen-Ren; Yu, Chun-Keung; Liu, Ching-Chuan

    2015-01-01

    Enterovirus 71 (EV71) infections may be associated with neurological complications, including brainstem encephalitis (BE). Severe EV71 BE may be complicated with autonomic nervous system (ANS) dysregulation and/or pulmonary edema (PE). ANS dysregulation is related to the overactivation of the sympathetic nervous system, which results from catecholamine release. The aims of this study were to explore the effects of catecholamines on severe EV71 infection and to investigate the changes in the percentages of EV71-infected cells, virus titer, and cytokine production on the involvement of catecholamines. Plasma levels of norepinephrine (NE) and epinephrine (EP) in EV71-infected patients were measured using an enzyme-linked immunoassay. The expression of adrenergic receptors (ADRs) on RD, A549, SK-N-SH, THP-1, Jurkat and human peripheral blood mononuclear cells (hPBMCs) were detected using flow cytometry. The percentages of EV71-infected cells, virus titer, and cytokine production were investigated after treatment with NE and EP. The plasma levels of NE and EP were significantly higher in EV71-infected patients with ANS dysregulation and PE than in controls. Both α1A- and β2-ADRs were expressed on A549, RD, SK-N-SH, HL-60, THP-1, Jurkat cells and hPBMCs. NE treatment elevated the percentages of EV71-infected cells to 62.9% and 22.7% in THP-1 and Jurkat cells, respectively. Via treatment with EP, the percentages of EV71-infected cells were increased to 64.6% and 26.9% in THP-1 and Jurkat cells. The percentage of EV71-infected cells increased upon NE or EP treatment while the α- and β-blockers reduced the percentages of EV71-infected cells with NE or EP treatment. At least two-fold increase in virus titer was observed in EV71-infected A549, SK-N-SH and hPBMCs after treatment with NE or EP. IL-6 production was enhanced in EV71-infected hPBMCs at a concentration of 102 pg/mL NE. The plasma levels of NE and EP elevated in EV71-infected patients with ANS dysregulation and

  4. Hepatitis B virus infection in Indonesia.

    Science.gov (United States)

    Yano, Yoshihiko; Utsumi, Takako; Lusida, Maria Inge; Hayashi, Yoshitake

    2015-10-14

    Approximately 240 million people are chronically infected with hepatitis B virus (HBV), 75% of whom reside in Asia. Approximately 600000 of infected patients die each year due to HBV-related diseases or hepatocellular carcinoma (HCC). The endemicity of hepatitis surface antigen in Indonesia is intermediate to high with a geographical difference. The risk of HBV infection is high in hemodialysis (HD) patients, men having sex with men, and health care workers. Occult HBV infection has been detected in various groups such as blood donors, HD patients, and HIV-infected individuals and children. The most common HBV subgenotype in Indonesia is B3 followed by C1. Various novel subgenotypes of HBV have been identified throughout Indonesia, with the novel HBV subgenotypes C6-C16 and D6 being successfully isolated. Although a number of HBV subgenotypes have been discovered in Indonesia, genotype-related pathogenicity has not yet been elucidated in detail. Therefore, genotype-related differences in the prognosis of liver disease and their effects on treatments need to be determined. A previous study conducted in Indonesia revealed that hepatic steatosis was associated with disease progression. Pre-S2 mutations and mutations at C1638T and T1753V in HBV/B3 have been associated with advanced liver diseases including HCC. However, drug resistance to lamivudine, which is prominent in Indonesia, remains obscure. Although the number of studies on HBV in Indonesia has been increasing, adequate databases on HBV infection are limited. We herein provided an overview of the epidemiology and clinical characteristics of HBV infection in Indonesia.

  5. Polysulfonate suramin inhibits Zika virus infection.

    Science.gov (United States)

    Tan, Chee Wah; Sam, I-Ching; Chong, Wei Lim; Lee, Vannajan Sanghiran; Chan, Yoke Fun

    2017-07-01

    Zika virus (ZIKV) is an arthropod-borne flavivirus that causes newborn microcephaly and Guillian-Barré syndrome in adults. No therapeutics are available to treat ZIKV infection or other flaviviruses. In this study, we explored the inhibitory effect of glycosaminoglycans and analogues against ZIKV infection. Highly sulfated heparin, dextran sulfate and suramin significantly inhibited ZIKV infection in Vero cells. De-sulfated heparin analogues lose inhibitory effect, implying that sulfonate groups are critical for viral inhibition. Suramin, an FDA-approved anti-parasitic drug, inhibits ZIKV infection with 3-5 log 10  PFU viral reduction with IC 50 value of ∼2.5-5 μg/ml (1.93 μM-3.85 μM). A time-of-drug-addition study revealed that suramin remains potent even when administrated at 1-24 hpi. Suramin inhibits ZIKV infection by preventing viral adsorption, entry and replication. Molecular dynamics simulation revealed stronger interaction of suramin with ZIKV NS3 helicase than with the envelope protein. Suramin warrants further investigation as a potential antiviral candidate for ZIKV infection. Heparan sulfate (HS) is a cellular attachment receptor for multiple flaviviruses. However, no direct ZIKV-heparin interaction was observed in heparin-binding analysis, and downregulate or removal of cellular HS with sodium chlorate or heparinase I/III did not inhibit ZIKV infection. This indicates that cell surface HS is not utilized by ZIKV as an attachment receptor. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Perinatal Chicken Pox (Varicella Zoster Virus Infection

    Directory of Open Access Journals (Sweden)

    Ali Annagur

    2013-04-01

    Full Text Available Chickenpox is due to infection with the varicella zoster virus (VZV, a human alphaherpervirus found worldwide. Classically, the cinical disease is a febrile illness with a pruritic vesicular rash. Maternal chickenpox between 5 days before delivery to 2 days after delivery (perinatal varicella can cause severe and even fatal illness in the newborn. A 7-day old girl baby presented on day 4 of postnatal with the complaints of widespread vesicular rash and non-suckling. Mother of the baby also had a similar eruption four day prior to delivery, which was clinically characteristic of varicella. Considering history and clinical presentation, a diagnosis of perinatal chickenpox was considered and the baby was treated with acyclovir which she responded and recovered. Herein, the clinical feasures and treatment of chickenpox infection in the perinatal period have been emphasized with this case report. [Cukurova Med J 2013; 38(2.000: 311-314

  7. Encephalomyocarditis virus infection in an Italian zoo

    Directory of Open Access Journals (Sweden)

    Pascotto Ernesto

    2010-03-01

    Full Text Available Abstract 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.

  8. Hepatitis C virus infection protein network.

    Science.gov (United States)

    de Chassey, B; Navratil, V; Tafforeau, L; Hiet, M S; Aublin-Gex, A; Agaugué, S; Meiffren, G; Pradezynski, F; Faria, B F; Chantier, T; Le Breton, M; Pellet, J; Davoust, N; Mangeot, P E; Chaboud, A; Penin, F; Jacob, Y; Vidalain, P O; Vidal, M; André, P; Rabourdin-Combe, C; Lotteau, V

    2008-01-01

    A proteome-wide mapping of interactions between hepatitis C virus (HCV) and human proteins was performed to provide a comprehensive view of the cellular infection. A total of 314 protein-protein interactions between HCV and human proteins was identified by yeast two-hybrid and 170 by literature mining. Integration of this data set into a reconstructed human interactome showed that cellular proteins interacting with HCV are enriched in highly central and interconnected proteins. A global analysis on the basis of functional annotation highlighted the enrichment of cellular pathways targeted by HCV. A network of proteins associated with frequent clinical disorders of chronically infected patients was constructed by connecting the insulin, Jak/STAT and TGFbeta pathways with cellular proteins targeted by HCV. CORE protein appeared as a major perturbator of this network. Focal adhesion was identified as a new function affected by HCV, mainly by NS3 and NS5A proteins.

  9. Disruption of Microtubules Post-Virus Entry Enhances Adeno-Associated Virus Vector Transduction

    Science.gov (United States)

    Xiao, Ping-Jie; Mitchell, Angela M.; Huang, Lu; Li, Chengwen; Samulski, R. Jude

    2016-01-01

    Perinuclear retention of viral particles is a poorly understood phenomenon observed during many virus infections. In this study, we investigated whether perinuclear accumulation acts as a barrier to limit recombinant adeno-associated virus (rAAV) transduction. After nocodazole treatment to disrupt microtubules at microtubule-organization center (MT-MTOC) after virus entry, we observed higher rAAV transduction. To elucidate the role of MT-MTOC in rAAV infection and study its underlying mechanisms, we demonstrated that rAAV's perinuclear localization was retained by MT-MTOC with fluorescent analysis, and enhanced rAAV transduction from MT-MTOC disruption was dependent on the rAAV capsid's nuclear import signals. Interestingly, after knocking down RhoA or inhibiting its downstream effectors (ROCK and Actin), MT-MTOC disruption failed to increase rAAV transduction or nuclear entry. These data suggest that enhancement of rAAV transduction is the result of increased trafficking to the nucleus via the RhoA-ROCK-Actin pathway. Ten-fold higher rAAV transduction was also observed by disrupting MT-MTOC in brain, liver, and tumor in vivo. In summary, this study indicates that virus perinuclear accumulation at MT-MTOC is a barrier-limiting parameter for effective rAAV transduction and defines a novel defense mechanism by which host cells restrain viral invasion. PMID:26942476

  10. Hepatitis C virus infection in the human immunodeficiency virus infected patient.

    Science.gov (United States)

    Clausen, Louise Nygaard; Lundbo, Lene Fogt; Benfield, Thomas

    2014-09-14

    Human immunodeficiency virus (HIV) and hepatitis C virus (HCV) share the same transmission routes; therefore, coinfection is frequent. An estimated 5-10 million individuals alone in the western world are infected with both viruses. The majority of people acquire HCV by injection drug use and, to a lesser extent, through blood transfusion and blood products. Recently, there has been an increase in HCV infections among men who have sex with men. In the context of effective antiretroviral treatment, liver-related deaths are now more common than Acquired Immune Deficiency Syndrome-related deaths among HIV-HCV coinfected individuals. Morbidity and mortality rates from chronic HCV infection will increase because the infection incidence peaked in the mid-1980s and because liver disease progresses slowly and is clinically silent to cirrhosis and end-stage-liver disease over a 15-20 year time period for 15%-20% of chronically infected individuals. HCV treatment has rapidly changed with the development of new direct-acting antiviral agents; therefore, cure rates have greatly improved because the new treatment regimens target different parts of the HCV life cycle. In this review, we focus on the epidemiology, diagnosis and the natural course of HCV as well as current and future strategies for HCV therapy in the context of HIV-HCV coinfection in the western world.

  11. Interaction of CtBP with adenovirus E1A suppresses immortalization of primary epithelial cells and enhances virus replication during productive infection

    Energy Technology Data Exchange (ETDEWEB)

    Subramanian, T.; Zhao, Ling-jun; Chinnadurai, G., E-mail: chinnag@slu.edu

    2013-09-01

    Adenovirus E1A induces cell proliferation, oncogenic transformation and promotes viral replication through interaction with p300/CBP, TRRAP/p400 multi-protein complex and the retinoblastoma (pRb) family proteins through distinct domains in the E1A N-terminal region. The C-terminal region of E1A suppresses E1A/Ras co-transformation and interacts with FOXK1/K2, DYRK1A/1B/HAN11 and CtBP1/2 (CtBP) protein complexes. To specifically dissect the role of CtBP interaction with E1A, we engineered a mutation (DL→AS) within the CtBP-binding motif, PLDLS, and investigated the effect of the mutation on immortalization and Ras cooperative transformation of primary cells and viral replication. Our results suggest that CtBP–E1A interaction suppresses immortalization and Ras co-operative transformation of primary rodent epithelial cells without significantly influencing the tumorigenic activities of transformed cells in immunodeficient and immunocompetent animals. During productive infection, CtBP–E1A interaction enhances viral replication in human cells. Between the two CtBP family proteins, CtBP2 appears to restrict viral replication more than CtBP1 in human cells. - Highlights: • Adenovirus E1A C-terminal region suppresses E1A/Ras co-transformation. • This E1A region binds with FOXK, DYRK1/HAN11 and CtBP cellular protein complexes. • We found that E1A–CtBP interaction suppresses immortalization and transformation. • The interaction enhances viral replication in human cells.

  12. Oral manifestations of hepatitis C virus infection

    Science.gov (United States)

    Carrozzo, Marco; Scally, Kara

    2014-01-01

    Extrahepatic manifestations (EHMs) of hepatitis C virus (HCV) infection can affect a variety of organ systems with significant morbidity and mortality. Some of the most frequently reported EHM of HCV infection, involve the oral region predominantly or exclusively. Oral lichen planus (OLP) is a chronic inflammatory condition that is potentially malignant and represents cell-mediated reaction to a variety of extrinsic antigens, altered self-antigens, or super antigens. Robust epidemiological evidence support the link between OLP and HCV. As the virus may replicate in the oral mucosa and attract HCV-specific T lymphocytes, HCV may be implicated in OLP pathogenesis. Sjögren syndrome (SjS) is an autoimmune exocrinopathy, characterized by dryness of the mouth and eyes and a multitude of other systemic signs and symptoms. SjS patients have also an increased risk of non-Hodgkin lymphoma. Patients with chronic hepatitis C do frequently have histological signs of Sjögren-like sialadenitis with mild or even absent clinical symptoms. However, it is still unclear if HCV may cause a disease mimicking SjS or it is directly responsible for the development of SjS in a specific subset of patients. Oral squamous cell carcinoma is the most common oral malignant tumour and at least in some part of the world could be linked to HCV. PMID:24976694

  13. Interaction of CtBP with adenovirus E1A suppresses immortalization of primary epithelial cells and enhances virus replication during productive infection.

    Science.gov (United States)

    Subramanian, T; Zhao, Ling-Jun; Chinnadurai, G

    2013-09-01

    Adenovirus E1A induces cell proliferation, oncogenic transformation and promotes viral replication through interaction with p300/CBP, TRRAP/p400 multi-protein complex and the retinoblastoma (pRb) family proteins through distinct domains in the E1A N-terminal region. The C-terminal region of E1A suppresses E1A/Ras co-transformation and interacts with FOXK1/K2, DYRK1A/1B/HAN11 and CtBP1/2 (CtBP) protein complexes. To specifically dissect the role of CtBP interaction with E1A, we engineered a mutation (DL→AS) within the CtBP-binding motif, PLDLS, and investigated the effect of the mutation on immortalization and Ras cooperative transformation of primary cells and viral replication. Our results suggest that CtBP-E1A interaction suppresses immortalization and Ras co-operative transformation of primary rodent epithelial cells without significantly influencing the tumorigenic activities of transformed cells in immunodeficient and immunocompetent animals. During productive infection, CtBP-E1A interaction enhances viral replication in human cells. Between the two CtBP family proteins, CtBP2 appears to restrict viral replication more than CtBP1 in human cells. Copyright © 2013 Elsevier Inc. All rights reserved.

  14. Transmission potential of Zika virus infection in the South Pacific

    Directory of Open Access Journals (Sweden)

    Hiroshi Nishiura

    2016-04-01

    Conclusions: The transmissibility of Zika virus infection appears to be comparable to those of dengue and chikungunya viruses. Considering that Aedes species are a shared vector, this finding indicates that Zika virus replication within the vector is perhaps comparable to dengue and chikungunya.

  15. Immune Activation in the Pathogenesis of Dengue Virus Infection

    NARCIS (Netherlands)

    C.A.M. van de Weg (Cornelia A.M.)

    2014-01-01

    markdownabstract__Abstract__ Dengue virus (DENV) is a positive-stranded RNA virus and belongs to the Flaviviridae family. The virus is transmitted by the bite of an infected Aedes-mosquito and circulates in tropical and subtropical areas around the world. The incidence of dengue has risen

  16. First Imported Case of Zika Virus Infection into Korea.

    Science.gov (United States)

    Jang, Hee-Chang; Park, Wan Beom; Kim, Uh Jin; Chun, June Young; Choi, Su-Jin; Choe, Pyoeng Gyun; Jung, Sook-In; Jee, Youngmee; Kim, Nam-Joong; Choi, Eun Hwa; Oh, Myoung-Don

    2016-07-01

    Since Zika virus has been spreading rapidly in the Americas from 2015, the outbreak of Zika virus infection becomes a global health emergency because it can cause neurological complications and adverse fetal outcome including microcephaly. Here, we report clinical manifestations and virus isolation findings from a case of Zika virus infection imported from Brazil. The patient, 43-year-old Korean man, developed fever, myalgia, eyeball pain, and maculopapular rash, but not neurological manifestations. Zika virus was isolated from his semen, and reverse-transcriptase PCR was positive for the virus in the blood, urine, and saliva on the 7th day of the illness but was negative on the 21st day. He recovered spontaneously without any neurological complications. He is the first case of Zika virus infection in Korea imported from Brazil.

  17. Negative-strand RNA viruses: The plant-infecting counterparts

    NARCIS (Netherlands)

    Kormelink, R.J.M.; Garcia, M.L.; Goodin, M.; Sasaya, T.; Haenni, A.L.

    2011-01-01

    While a large number of negative-strand (-)RNA viruses infect animals and humans, a relative small number have plants as their primary host. Some of these have been classified within families together with animal/human infecting viruses due to similarities in particle morphology and genome

  18. Zika virus infection acquired during brief travel to Indonesia.

    Science.gov (United States)

    Kwong, Jason C; Druce, Julian D; Leder, Karin

    2013-09-01

    Zika virus infection closely resembles dengue fever. It is possible that many cases are misdiagnosed or missed. We report a case of Zika virus infection in an Australian traveler who returned from Indonesia with fever and rash. Further case identification is required to determine the evolving epidemiology of this disease.

  19. Diagnosis and Management of Paediatric Hepatitis C Virus Infection ...

    African Journals Online (AJOL)

    Background: HepatitisC virus is a chronic life-long infection in themajority of patientswho are infected with the virus.Without accurate diagnosis and follow up, these children cannot be offered optimal care, and are at risk of presenting in adult life with significant liver pathology and long-term sequelae. Objective: To explore ...

  20. Hepatitis B Virus infection in Nigeria – a review | Emechebe ...

    African Journals Online (AJOL)

    ... virus in the general population also play role in Nigeria. Conclusion: Reduction in the of hepatitis B virus infection could be achieved by public enlightenment campaign, mass immunization of the children and adults at risk while antiviral drugs and immunostimulatory therapy should be provided for those already infected.

  1. Transfusion associated hepatitis B virus infection among sickle cell ...

    African Journals Online (AJOL)

    Background: Transfusion of blood products is a recognised way of transmitting infections particularly viruses. The extent to which blood transfusion contributes to hepatitis B virus (HBV) infections in transfused patients with sickle cell anaemia (SCA) has been found to be 20% in Lagos, Nigeria. Mamman in Zaria however ...

  2. Postmortem Findings for 7 Neonates with Congenital Zika Virus Infection.

    Science.gov (United States)

    Sousa, Anastácio Q; Cavalcante, Diane I M; Franco, Luciano M; Araújo, Fernanda M C; Sousa, Emília T; Valença-Junior, José Telmo; Rolim, Dionne B; Melo, Maria E L; Sindeaux, Pedro D T; Araújo, Marialva T F; Pearson, Richard D; Wilson, Mary E; Pompeu, Margarida M L

    2017-07-01

    Postmortem examination of 7 neonates with congenital Zika virus infection in Brazil revealed microcephaly, ventriculomegaly, dystrophic calcifications, and severe cortical neuronal depletion in all and arthrogryposis in 6. Other findings were leptomeningeal and brain parenchymal inflammation and pulmonary hypoplasia and lymphocytic infiltration in liver and lungs. Findings confirmed virus neurotropism and multiple organ infection.

  3. An autochthonous sexually transmitted Zika virus infection in Italy 2016.

    Science.gov (United States)

    Grossi, Paolo Antonio; Percivalle, Elena; Campanini, Giulia; Sarasini, Antonella; Premoli, Marta; Zavattoni, Maurizio; Girello, Alessia; Dalla Gasperina, Daniela; Balsamo, Maria Luisa; Baldanti, Fausto; Rovida, Francesca

    2018-01-01

    We describe two cases of Zika virus infection involving an Italian patient returning from the Dominican Republic and his wife, who remained in Italy and had not travelled to Zika virus endemic areas in the previous months. The infection was transmitted through unprotected sexual intercourse after the man's return to Italy.

  4. Phyllanthus species for chronic hepatitis B virus infection

    DEFF Research Database (Denmark)

    Yun, Xia; Luo, Hui; Liu, Jian Ping

    2011-01-01

    Phyllanthus species for patients with chronic hepatitis B virus (HBV) infection have been assessed in clinical trials, but no consensus regarding their usefulness exists.......Phyllanthus species for patients with chronic hepatitis B virus (HBV) infection have been assessed in clinical trials, but no consensus regarding their usefulness exists....

  5. Co-infections with Chikungunya and Dengue Viruses, Guatemala, 2015.

    Science.gov (United States)

    Edwards, Thomas; Signor, Leticia Del Carmen Castillo; Williams, Christopher; Donis, Evelin; Cuevas, Luis E; Adams, Emily R

    2016-11-01

    We screened serum samples referred to the national reference laboratory in Guatemala that were positive for chikungunya or dengue viruses in June 2015. Co-infection with both viruses was detected by reverse transcription PCR in 46 (32%) of 144 samples. Specimens should be tested for both arboviruses to detect co-infections.

  6. Susceptibility of different leukocyte cell types to Vaccinia virus infection

    Directory of Open Access Journals (Sweden)

    Sánchez-Puig Juana M

    2004-11-01

    Full Text Available Abstract Background Vaccinia virus, the prototype member of the family Poxviridae, was used extensively in the past as the Smallpox vaccine, and is currently considered as a candidate vector for new recombinant vaccines. Vaccinia virus has a wide host range, and is known to infect cultures of a variety of cell lines of mammalian origin. However, little is known about the virus tropism in human leukocyte populations. We report here that various cell types within leukocyte populations have widely different susceptibility to infection with vaccinia virus. Results We have investigated the ability of vaccinia virus to infect human PBLs by using virus recombinants expressing green fluorescent protein (GFP, and monoclonal antibodies specific for PBL subpopulations. Flow cytometry allowed the identification of infected cells within the PBL mixture 1–5 hours after infection. Antibody labeling revealed that different cell populations had very different infection rates. Monocytes showed the highest percentage of infected cells, followed by B lymphocytes and NK cells. In contrast to those cell types, the rate of infection of T lymphocytes was low. Comparison of vaccinia virus strains WR and MVA showed that both strains infected efficiently the monocyte population, although producing different expression levels. Our results suggest that MVA was less efficient than WR in infecting NK cells and B lymphocytes. Overall, both WR and MVA consistently showed a strong preference for the infection of non-T cells. Conclusions When infecting fresh human PBL preparations, vaccinia virus showed a strong bias towards the infection of monocytes, followed by B lymphocytes and NK cells. In contrast, very poor infection of T lymphocytes was detected. These finding may have important implications both in our understanding of poxvirus pathogenesis and in the development of improved smallpox vaccines.

  7. Dendritic cells in dengue virus infection: Targets of virus replication and mediators of immunity

    Directory of Open Access Journals (Sweden)

    Michael A. Schmid

    2014-12-01

    Full Text Available Dendritic cells (DCs are sentinels of the immune system and detect pathogens at sites of entry, such as the skin. In addition to the ability of DCs to control infections directly via their innate immune functions, DCs help to prime adaptive B and T cell responses via antigen presentation in lymphoid tissues. Infected Aedes aegypti or Ae. albopictus mosquitoes transmit the four dengue virus (DENV serotypes to humans while probing for small blood vessels in the skin. DENV causes the most prevalent arthropod-borne viral disease in humans, yet no vaccine or specific therapeutic is currently approved. Although primary DENV infection confers life-long protective immunity against re-infection with the same DENV serotype, secondary infection with a different DENV serotype can lead to increased disease severity via cross-reactive T cells or enhancing antibodies. This review summarizes recent findings in humans and animal models about DENV infection of DCs, monocytes and macrophages. We discuss the dual role of DCs as both targets of DENV replication and mediators of innate and adaptive immunity, and summarize immune evasion strategies whereby DENV impairs the function of infected DCs. We suggest that DCs play a key role in priming DENV-specific neutralizing or potentially harmful memory B and T cell responses, and that future DC-directed therapies may help induce protective memory responses and reduce dengue pathogenesis.

  8. Immunomodulatory Activity of Red Ginseng against Influenza A Virus Infection

    Directory of Open Access Journals (Sweden)

    Jong Seok Lee

    2014-01-01

    Full Text Available Ginseng herbal medicine has been known to have beneficial effects on improving human health. We investigated whether red ginseng extract (RGE has preventive effects on influenza A virus infection in vivo and in vitro. RGE was found to improve survival of human lung epithelial cells upon influenza virus infection. Also, RGE treatment reduced the expression of pro-inflammatory genes (IL-6, IL-8 probably in part through interference with the formation of reactive oxygen species by influenza A virus infection. Long-term oral administration of mice with RGE showed multiple immunomodulatory effects such as stimulating antiviral cytokine IFN-γ production after influenza A virus infection. In addition, RGE administration in mice inhibited the infiltration of inflammatory cells into the bronchial lumens. Therefore, RGE might have the potential beneficial effects on preventing influenza A virus infections via its multiple immunomodulatory functions.

  9. Effect of low-pathogenicity influenza virus H3N8 infection on Mycoplasma gallisepticum infection of chickens.

    Science.gov (United States)

    Stipkovits, Laszlo; Egyed, Laszlo; Palfi, Vilmos; Beres, Andrea; Pitlik, Ervin; Somogyi, Maria; Szathmary, Susan; Denes, Bela

    2012-01-01

    Mycoplasma infection is still very common in chicken and turkey flocks. Several low-pathogenicity avian influenza (LPAI) viruses are circulating in wild birds that can be easily transmitted to poultry flocks. However, the effect of LPAI on mycoplasma infection is not well understood. The aim of the present study was to investigate the infection of LPAI virus H3N8 (A/mallard/Hungary/19616/07) in chickens challenged with Mycoplasma gallisepticum. Two groups of chickens were aerosol challenged with M. gallisepticum. Later one of these groups and one mycoplasma-free group were aerosol challenged with the LPAI H3N8 virus. The birds were observed for clinical signs for 8 days, then euthanized, and examined for the presence of M. gallisepticum in the trachea, lung, air sac, liver, spleen, kidney and heart, and for developing anti-mycoplasma and anti-viral antibodies. The LPAI H3N8 virus did not cause any clinical signs but M. gallisepticum infection caused clinical signs, reduction of body weight gain and colonization of the inner organs. These parameters were more severe in the birds co-infected with M. gallisepticum and LPAI H3N8 virus than in the group challenged with M. gallisepticum alone. In addition, in the birds infected with both M. gallisepticum and LPAI H3N8 virus, the anti-mycoplasma antibody response was reduced significantly when compared with the group challenged with M. gallisepticum alone. Co-infection with LPAI H3N8 virus thus enhanced pathogenesis of M. gallisepticum infection significantly.

  10. A role for airway remodeling during respiratory syncytial virus infection

    Directory of Open Access Journals (Sweden)

    Dimina Dawn M

    2005-10-01

    Full Text Available Abstract Background Severe respiratory syncytial virus infection (RSV during infancy has been shown to be a major risk factor for the development of subsequent wheeze. However, the reasons for this link remain unclear. The objective of this research was to determine the consequences of early exposure to RSV and allergen in the development of subsequent airway hyperreactivity (AHR using a developmental time point in the mouse that parallels that of the human neonate. Methods Weanling mice were sensitized and challenged with ovalbumin (Ova and/or infected with RSV. Eight days after the last allergen challenge, various pathophysiological endpoints were examined. Results AHR in response to methacholine was enhanced only in weanling mice exposed to Ova and subsequently infected with RSV. The increase in AHR appeared to be unrelated to pulmonary RSV titer. Total bronchoalveolar lavage cellularity in these mice increased approximately two-fold relative to Ova alone and was attributable to increases in eosinophil and lymphocyte numbers. Enhanced pulmonary pathologies including persistent mucus production and subepithelial fibrosis were observed. Interestingly, these data correlated with transient increases in TNF-α, IFN-γ, IL-5, and IL-2. Conclusion The observed changes in pulmonary structure may provide an explanation for epidemiological data suggesting that early exposure to allergens and RSV have long-term physiological consequences. Furthermore, the data presented here highlight the importance of preventative strategies against RSV infection of atopic individuals during neonatal development.

  11. The Laboratory Diagnosis of Herpes Simplex Virus Infections

    Directory of Open Access Journals (Sweden)

    Ameeta Singh

    2005-01-01

    Full Text Available Herpes simplex virus (HSV types 1 and 2 cause genital herpes infections and are the most common cause of genital ulcer disease in industrialized nations. Although these infections are very common, the majority of them remain underdiagnosed because they are asymptomatic or unrecognized. A clinical diagnosis of genital herpes should always be confirmed by laboratory testing; this can be accomplished through the use of direct tests for viral isolation, the detection of antigen or, more recently, the detection of HSV DNA using molecular diagnostic techniques. Testing for serotypes is recommended because of the different prognostic and counselling implications. Type-specific HSV serology is becoming more readily available and will enhance the ability to make the diagnosis and guide clinical management in select patients.

  12. Is ultraviolet enhanced reactivation of mammalian virus mutagenic

    International Nuclear Information System (INIS)

    Bockstahler, L.E.; Hellman, K.B.; Cantwell, J.M.; Strickland, A.

    1981-01-01

    Ultraviolet enhanced reactivation consists of an increase in the survival of certain uv-irradiated mammalian viruses when assayed for infectivity in uv-irradiated host mammalian cells, as compared with unirradiated cells. In this report ultraviolet enhanced reactivation is described, and a review is presented of investigations from this and other laboratories to establish whether or not this process is mutagenic. The answer to this question may help establish if error-prone DNA repair is induced in irradiated mammalian cells. We approached the mutagenesis question by examining the phenotypic reversion of a uv-irradiated temperature sensitive mutant of Herpes simplex virus to wild type growth in uv-irradiated monkey kidney cells. Apparent reversion was observed in both irradiated and unirradiated cells. No correlation could be found between the extent of reversion and uv exposure to the cells. The conclusions from studies reported by other investigators using various mammalian virus mutagenesis systems are conflicting. It was generally agreed that viral mutagenesis occurs when irradiated virus is passaged through either irradiated or unexposed cells. However, in some studies it was found that the frequency of mutagenesis in irradiated cells was greater than that in unirradiated cells, while in other studies increased mutagenesis in irradiated cells was not observed

  13. Plant RNA Regulatory Network and RNA Granules in Virus Infection

    Directory of Open Access Journals (Sweden)

    Kristiina Mäkinen

    2017-12-01

    Full Text Available Regulation of post-transcriptional gene expression on mRNA level in eukaryotic cells includes translocation, translation, translational repression, storage, mRNA decay, RNA silencing, and nonsense-mediated decay. These processes are associated with various RNA-binding proteins and cytoplasmic ribonucleoprotein complexes many of which are conserved across eukaryotes. Microscopically visible aggregations formed by ribonucleoprotein complexes are termed RNA granules. Stress granules where the translationally inactive mRNAs are stored and processing bodies where mRNA decay may occur present the most studied RNA granule types. Diverse RNP-granules are increasingly being assigned important roles in viral infections. Although the majority of the molecular level studies on the role of RNA granules in viral translation and replication have been conducted in mammalian systems, some studies link also plant virus infection to RNA granules. An increasing body of evidence indicates that plant viruses require components of stress granules and processing bodies for their replication and translation, but how extensively the cellular mRNA regulatory network is utilized by plant viruses has remained largely enigmatic. Antiviral RNA silencing, which is an important regulator of viral RNA stability and expression in plants, is commonly counteracted by viral suppressors of RNA silencing. Some of the RNA silencing suppressors localize to cellular RNA granules and have been proposed to carry out their suppression functions there. Moreover, plant nucleotide-binding leucine-rich repeat protein-mediated virus resistance has been linked to enhanced processing body formation and translational repression of viral RNA. Many interesting questions relate to how the pathways of antiviral RNA silencing leading to viral RNA degradation and/or repression of translation, suppression of RNA silencing and viral RNA translation converge in plants and how different RNA granules and

  14. Plant RNA Regulatory Network and RNA Granules in Virus Infection.

    Science.gov (United States)

    Mäkinen, Kristiina; Lõhmus, Andres; Pollari, Maija

    2017-01-01

    Regulation of post-transcriptional gene expression on mRNA level in eukaryotic cells includes translocation, translation, translational repression, storage, mRNA decay, RNA silencing, and nonsense-mediated decay. These processes are associated with various RNA-binding proteins and cytoplasmic ribonucleoprotein complexes many of which are conserved across eukaryotes. Microscopically visible aggregations formed by ribonucleoprotein complexes are termed RNA granules. Stress granules where the translationally inactive mRNAs are stored and processing bodies where mRNA decay may occur present the most studied RNA granule types. Diverse RNP-granules are increasingly being assigned important roles in viral infections. Although the majority of the molecular level studies on the role of RNA granules in viral translation and replication have been conducted in mammalian systems, some studies link also plant virus infection to RNA granules. An increasing body of evidence indicates that plant viruses require components of stress granules and processing bodies for their replication and translation, but how extensively the cellular mRNA regulatory network is utilized by plant viruses has remained largely enigmatic. Antiviral RNA silencing, which is an important regulator of viral RNA stability and expression in plants, is commonly counteracted by viral suppressors of RNA silencing. Some of the RNA silencing suppressors localize to cellular RNA granules and have been proposed to carry out their suppression functions there. Moreover, plant nucleotide-binding leucine-rich repeat protein-mediated virus resistance has been linked to enhanced processing body formation and translational repression of viral RNA. Many interesting questions relate to how the pathways of antiviral RNA silencing leading to viral RNA degradation and/or repression of translation, suppression of RNA silencing and viral RNA translation converge in plants and how different RNA granules and their individual

  15. Prevalence of occult hepatitis C virus infection in the Iranian patients with human immunodeficiency virus infection.

    Science.gov (United States)

    Bokharaei-Salim, Farah; Keyvani, Hossein; Esghaei, Maryam; Zare-Karizi, Shohreh; Dermenaki-Farahani, Sahar-Sadat; Hesami-Zadeh, Khashayar; Fakhim, Shahin

    2016-11-01

    Occult hepatitis C virus (HCV) infection is a new form of chronic HCV infection described by the presence of the genomic HCV-RNA in liver biopsy and/or peripheral blood mononuclear cell (PBMC) samples, and undetectable levels or absence of HCV-RNA and in the absence or presence of anti HCV antibodies in the plasma specimens. The aim of the present study was to evaluate the occurrence of occult HCV infection (OCI) among Iranian subjects infected with human immunodeficiency virus (HIV) using RT-nested PCR. From March 2014 until April 2015, 109 Iranian patients with established HIV infection were enrolled in this cross-sectional study. After extraction of viral RNA from the plasma and PBMC samples, HCV-RNA status was examined by RT-nested PCR using primers from the 5'-NTR. HCV genotyping was conducted using RFLP analysis. For the confirmation of HCV genotyping by RFLP method, the PCR products were sequenced. Of the 109 patients, 50 were positive for antibodies against HCV. The HCV-RNA was detected in PBMC specimens in 6 (10.2%) out of the total 59 patients negative for anti-HCV Abs and undetectable plasma HCV-RNA and also from 4 (8.0%) out of the total 50 patients positive for anti-HCV Abs and undetectable plasma HCV-RNA. HCV genotyping analysis showed that 6 (60.0%) patients were infected with HCV subtype 3a, 3 (30.0%) were infected with HCV subtype 1a and 1 (10.0%) patient was infected with HCV subtype 1b. This study revealed the incidence of OCI (9.2%) in HIV-infected Iranian patients. Hence, designing prospective studies focusing on the detection of OCI in these patients would provide more information. J. Med. Virol. 88:1960-1966, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  16. Hepatitis B virus infection in children.

    LENUS (Irish Health Repository)

    O'Gorman, C S

    2012-02-01

    Recent increases in Hepatitis B virus (HBV) infection prompted us to characterize HBV-infected children in Ireland and to audit management, by reviewing prospectively gathered data. Of 46 children (29 [63%] male), median age at presentation was 8.1 years (range 0.6-17.6), monitoring duration was 22.5 months (range 1-101), 23\\/46 (50%) were European (including 9 [19.6%] Irish), 15 (32.6%) African and 9 (19.6%) Asian. Acquisition was vertical (25\\/46 [54.3%]), horizontal (5\\/46 [10.9%]), unknown (16\\/46 [34.8%]). HBV-DNA was >100,000,000 cpm in 20\\/32 (62.5%) with chronic infection. Hepatitis B e antigen (HBeAg) was detected in 32\\/44 (72.7%). We estimate that universal neonatal vaccination (UNV-HBV) could have prevented 22% of cases, and could limit further horizontal HBV spread. This supports the recent introduction of UNV-HBV.

  17. Microbiological diagnosis of human papilloma virus infection.

    Science.gov (United States)

    Mateos-Lindemann, Maria Luisa; Pérez-Castro, Sonia; Rodríguez-Iglesias, Manuel; Pérez-Gracia, Maria Teresa

    2017-11-01

    Infection with human papillomavirus (HPV) is the leading cause of sexually transmitted infection worldwide. This virus generally causes benign lesions, such as genital warts, but persistent infection may lead to cervical cancer, anal cancer, vaginal cancer, and oropharyngeal cancer, although less frequently. Cervical cancer is a severe disease with a high mortality in some countries. Screening with cytology has been very successful in the last few years, but nowadays there are numerous studies that confirm that cytology should be replaced with the detection of HPV as a first line test in population based screening. There are several commercially available FDA approved tests for screening of cervical cancer. A new strategy, based on individual detection of the high risk genotypes HPV16 and HPV18, present in 70% of cervical cancer biopsies, has been proposed by some experts, and is going to be implemented in most countries in the future. Copyright © 2016 Elsevier España, S.L.U. and Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

  18. Epidemiological studies on viral infections and co-infections : Human immunodeficiency virus, hepatitis C virus and human papillomavirus

    NARCIS (Netherlands)

    van Santen, D.K.

    2018-01-01

    The research described in this thesis aimed to increase our understanding of the incidence, disease progression and treatment of human immunodeficiency virus (HIV), hepatitis C virus (HCV), and human papillomavirus (HPV) infections and co-infections in key populations. Chapter 1 contains an overview

  19. Enhanced Ex Vivo Stimulation of Mycobacterium tuberculosis-Specific T Cells in Human Immunodeficiency Virus-Infected Persons via Antigen Delivery by the Bordetella pertusis Adenylate Cyclase Vector

    Czech Academy of Sciences Publication Activity Database

    Connell, T. G.; Shey, M. S.; Seldon, R.; Rangaka, M. X.; van Cutsem, G.; Šimšová, Marcela; Marčeková, Zuzana; Šebo, Peter; Curtis, N.; Diwakar, L.; Meintjes, G. A.; Leclerc, C.; Wilkinson, R. J.; Wilkinson, K. A.

    2007-01-01

    Roč. 14, č. 7 (2007), s. 847-854 ISSN 1556-6811 R&D Projects: GA MŠk 2B06161 Institutional research plan: CEZ:AV0Z50200510 Keywords : mycobacterium tuberculosis * bordetella pertusis * human immunodeficiency virus Subject RIV: EE - Microbiology, Virology Impact factor: 1.995, year: 2007

  20. Sofosbuvir treatment and hepatitis C virus infection

    Science.gov (United States)

    Nakamura, Masato; Kanda, Tatsuo; Haga, Yuki; Sasaki, Reina; Wu, Shuang; Nakamoto, Shingo; Yasui, Shin; Arai, Makoto; Imazeki, Fumio; Yokosuka, Osamu

    2016-01-01

    Hepatitis C virus (HCV) infection is a serious problem worldwide. The use of interferon-based therapy has made HCV eradication challenging. The recent appearance of direct-acting antiviral agents (DAAs) has changed HCV therapy. Combining the use of DAAs with peginterferon and ribavirin has improved treatment efficacy. Furthermore, the combination of different orally administered DAAs has enabled interferon-free therapy with much higher efficacy and safety. In particular, sofosbuvir, a nucleotide-based NS5B inhibitor, prevents HCV RNA synthesis by acting as a “chain terminator”. Treatment with sofosbuvir has attained an extremely high rate of sustained virologic response. The current review summarizes the efficacy and safety of sofosbuvir therapy. PMID:26839641

  1. Zika Virus Infects, Activates, and Crosses Brain Microvascular Endothelial Cells, without Barrier Disruption

    Science.gov (United States)

    Papa, Michelle P.; Meuren, Lana M.; Coelho, Sharton V. A.; Lucas, Carolina G. de Oliveira; Mustafá, Yasmin M.; Lemos Matassoli, Flavio; Silveira, Paola P.; Frost, Paula S.; Pezzuto, Paula; Ribeiro, Milene R.; Tanuri, Amilcar; Nogueira, Mauricio L.; Campanati, Loraine; Bozza, Marcelo T.; Paula Neto, Heitor A.; Pimentel-Coelho, Pedro M.; Figueiredo, Claudia P.; de Aguiar, Renato S.; de Arruda, Luciana B.

    2017-01-01

    Zika virus (ZIKV) has been associated to central nervous system (CNS) harm, and virus was detected in the brain and cerebrospinal fluids of microcephaly and meningoencephalitis cases. However, the mechanism by which the virus reaches the CNS is unclear. Here, we addressed the effects of ZIKV replication in human brain microvascular endothelial cells (HBMECs), as an in vitro model of blood brain barrier (BBB), and evaluated virus extravasation and BBB integrity in an in vivo mouse experimental model. HBMECs were productively infected by African and Brazilian ZIKV strains (ZIKVMR766 and ZIKVPE243), which induce increased production of type I and type III IFN, inflammatory cytokines and chemokines. Infection with ZIKVMR766 promoted earlier cellular death, in comparison to ZIKVPE243, but infection with either strain did not result in enhanced endothelial permeability. Despite the maintenance of endothelial integrity, infectious virus particles crossed the monolayer by endocytosis/exocytosis-dependent replication pathway or by transcytosis. Remarkably, both viruses' strains infected IFNAR deficient mice, with high viral load being detected in the brains, without BBB disruption, which was only detected at later time points after infection. These data suggest that ZIKV infects and activates endothelial cells, and might reach the CNS through basolateral release, transcytosis or transinfection processes. These findings further improve the current knowledge regarding ZIKV dissemination pathways. PMID:29312238

  2. Temporal Analysis of Andes Virus and Sin Nombre Virus Infections of Syrian Hamsters

    Science.gov (United States)

    2007-05-01

    Microbiology . All Rights Reserved. Temporal Analysis of Andes Virus and Sin Nombre Virus Infections of Syrian Hamsters Victoria Wahl-Jensen,1 Jennifer...Ye, C., J. Prescott , R. Nofchissey, D. Goade, and B. Hjelle. 2004. Neutralizing antibodies and Sin Nombre virus RNA after recovery from hantavirus

  3. «I Am Legend»: comparison of the fictional virus infection and Rabies virus

    Directory of Open Access Journals (Sweden)

    José Francisco CAMACHO AGUILERA

    2016-04-01

    Full Text Available Using the movie I am legend (2007 by, the rabies virus infection is reviewed in this article, given its strong resemblance to the fictional disease created in this film caused by the virus Krippin. A review of history, virus characteristics, viral transmission, clinical manifestations, diagnostics, mortality, treatment and prevention, are presented and are contrasted with the film.

  4. West Nile virus meningitis in a patient with human immunodeficiency virus type 1 infection

    Directory of Open Access Journals (Sweden)

    D. Pilalas

    2017-09-01

    Full Text Available The emergence of West Nile virus lineage 2 in central Macedonia, Greece, in 2010 resulted in large outbreaks for 5 consecutive years. We report a case of viral meningitis in an individual infected with human immunodeficiency virus type 1, which preceded the recognition of the outbreak and was confirmed retrospectively as West Nile virus neuroinvasive disease.

  5. Doubled dosage of sofosbuviris expected for inhibiting Zika virus infection

    Institute of Scientific and Technical Information of China (English)

    Somsri Wiwanitkit; Viroj Wiwanitkit

    2017-01-01

    Sofosbuvir is a new antiviral drug that has been recommended for management of hepatitis C virus (HCV) for a few years. New researches support that sofosbuvir might be useful for the management of Zika virus infection. Based on the pharmacological activity, inhibiting the HCV RNA-dependent RNA polymerase (RdRp or NS5 protein), sofosbuvir is proposed for its effectiveness against Zika virus infection. Here, the authors used a mathematical modelling theoretical approach to predict the expected dosage of sofosbuvir for inhibiting Zika virus infection. Based on the modeling study, if sofosbuvir is assigned for management of Zika virus infection, doubled dosage of the present dosage for hepatitis C management is recommended.

  6. Newcastle disease virus triggers autophagy in U251 glioma cells to enhance virus replication.

    Science.gov (United States)

    Meng, Chunchun; Zhou, Zhizhi; Jiang, Ke; Yu, Shengqing; Jia, Lijun; Wu, Yantao; Liu, Yanqing; Meng, Songshu; Ding, Chan

    2012-06-01

    Newcastle disease virus (NDV) can replicate in tumor cells and induce apoptosis in late stages of infection. However, the interaction between NDV and cells in early stages of infection is not well understood. Here, we report that, shortly after infection, NDV triggers the formation of autophagosomes in U251 glioma cells, as demonstrated by an increased number of double-membrane vesicles, GFP-microtubule-associated protein 1 light chain 3 (GFP-LC3) a dot formations, and elevated production of LC3II. Moreover, modulation of NDV-induced autophagy by rapamycin, chloroquine or small interfering RNAs targeting the genes critical for autophagosome formation (Atg5 and Beclin-1) affects virus production, indicating that autophagy may be utilized by NDV to facilitate its own production. Furthermore, the class III phosphatidylinositol 3-kinase (PI3K)/Beclin-1 pathway plays a role in NDV-induced autophagy and virus production. Collectively, our data provide a unique example of a paramyxovirus that uses autophagy to enhance its production.

  7. Infection of endothelial cells by common human viruses.

    Science.gov (United States)

    Friedman, H M

    1989-01-01

    Common human viruses were evaluated for their ability to replicate in the endothelial cells of human umbilical vein and bovine thoracic aorta in vitro. Infection occurred with most viruses. The susceptibilities of endothelial cells derived from bovine aorta, pulmonary artery, and vena cava were compared. Among the viruses studied, no differences were noted in the ability to grow in endothelial cells from these three large vessels. One virus, herpes simplex virus type 1, was evaluated for its ability to produce persistent infection of endothelial cells. Infection developed and persisted for up to 3 months. After the first week, productive infection was found in less than 1% of cells. Nevertheless, the infection markedly affected the growth and morphology of the endothelial monolayer. Infection with any of several different viruses was noted to alter endothelial cell functions, including adherence of granulocytes, production of colony-stimulating factor, and synthesis of matrix protein. In addition, herpes simplex virus type 1 induced receptors for the Fc portion of IgG and for complement component C3b. These findings indicate that common human viruses can profoundly affect the biology of the endothelium.

  8. A novel single virus infection system reveals that influenza virus preferentially infects cells in g1 phase.

    Directory of Open Access Journals (Sweden)

    Ryuta Ueda

    Full Text Available BACKGROUND: Influenza virus attaches to sialic acid residues on the surface of host cells via the hemagglutinin (HA, a glycoprotein expressed on the viral envelope, and enters into the cytoplasm by receptor-mediated endocytosis. The viral genome is released and transported in to the nucleus, where transcription and replication take place. However, cellular factors affecting the influenza virus infection such as the cell cycle remain uncharacterized. METHODS/RESULTS: To resolve the influence of cell cycle on influenza virus infection, we performed a single-virus infection analysis using optical tweezers. Using this newly developed single-virus infection system, the fluorescence-labeled influenza virus was trapped on a microchip using a laser (1064 nm at 0.6 W, transported, and released onto individual H292 human lung epithelial cells. Interestingly, the influenza virus attached selectively to cells in the G1-phase. To clarify the molecular differences between cells in G1- and S/G2/M-phase, we performed several physical and chemical assays. Results indicated that: 1 the membranes of cells in G1-phase contained greater amounts of sialic acids (glycoproteins than the membranes of cells in S/G2/M-phase; 2 the membrane stiffness of cells in S/G2/M-phase is more rigid than those in G1-phase by measurement using optical tweezers; and 3 S/G2/M-phase cells contained higher content of Gb3, Gb4 and GlcCer than G1-phase cells by an assay for lipid composition. CONCLUSIONS: A novel single-virus infection system was developed to characterize the difference in influenza virus susceptibility between G1- and S/G2/M-phase cells. Differences in virus binding specificity were associated with alterations in the lipid composition, sialic acid content, and membrane stiffness. This single-virus infection system will be useful for studying the infection mechanisms of other viruses.

  9. Human Immunodeficiency Virus Infection in Pregnancy

    Directory of Open Access Journals (Sweden)

    Yasemin Arikan

    1998-01-01

    Full Text Available The incidence and prevalence of human immunodeficiency virus (HIV infection in women of child-bearing age continue to increase both internationally and in Canada. The care of HIV-infected pregnant women is complex, and multiple issues must be addressed, including the current and future health of the woman, minimization of the risk of maternal-infant HIV transmission, and maintenance of the well-being of the fetus and neonate. Vertical transmission of HIV can occur in utero, intrapartum and postpartum, but current evidence suggests that the majority of transmission occurs toward end of term, or during labour and delivery. Several maternal and obstetrical factors influence transmission rates, which can be reduced by optimal medical and obstetrical care. Zidovudine therapy has been demonstrated to reduce maternal-infant transmission significantly, but several issues, including the short and long term safety of antiretrovirals and the optimal use of combination antiretroviral therapy in pregnancy, remain to be defined. It is essential that health care workers providing care to these women fully understand the natural history of HIV disease in pregnancy, the factors that affect vertical transmission and the management issues during pregnancy. Close collaboration among a multidisciplinary team of knowledgeable health professionals and, most importantly, the woman herself can improve both maternal and infant outcomes.

  10. Reference gene selection for quantitative real-time PCR analysis in virus infected cells: SARS corona virus, Yellow fever virus, Human Herpesvirus-6, Camelpox virus and Cytomegalovirus infections

    Directory of Open Access Journals (Sweden)

    Müller Marcel A

    2005-02-01

    Full Text Available Abstract Ten potential reference genes were compared for their use in experiments investigating cellular mRNA expression of virus infected cells. Human cell lines were infected with Cytomegalovirus, Human Herpesvirus-6, Camelpox virus, SARS coronavirus or Yellow fever virus. The expression levels of these genes and the viral replication were determined by real-time PCR. Genes were ranked by the BestKeeper tool, the GeNorm tool and by criteria we reported previously. Ranking lists of the genes tested were tool dependent. However, over all, β-actin is an unsuitable as reference gene, whereas TATA-Box binding protein and peptidyl-prolyl-isomerase A are stable reference genes for expression studies in virus infected cells.

  11. Human immunodeficiency virus infection presenting as a fatal case ...

    African Journals Online (AJOL)

    MJP

    2015-06-25

    Jun 25, 2015 ... original work is properly cited. Human immunodeficiency virus infection presenting as a fatal ... of neurological symptoms by an infection (upper respiratory tract infection or diarrhea), in a smaller proportion of .... cerebrospinal fluid findings of albumino-cytology dissociation.[6]. However, albumino-cytology.

  12. Hepatitis C virus infection in Saudi Arabian recipients of renal ...

    African Journals Online (AJOL)

    Background: Studies of recipients most of whom had been infected prior to transplantation, had yielded conflicting conclusions in regard to the clinical impact of hepatitis C virus [HCV] infection. We determined the frequency of new. HCV infection and assessed its effect on patient and graft survival and occurrence of chronic ...

  13. Prevalence of Hepatitis B virus infection amongst parturients in the ...

    African Journals Online (AJOL)

    Background: Hepatitis B virus (HBV) infection is endemic in Nigeria and indeed the whole of Sub-Saharan Africa. The Society of Gastroenterology and Hepatology in Nigeria (SOGHIN) recommends HBV screening for all Nigerians to pave way for early detection and treatment of the infection in those who are infected and ...

  14. Zika virus infection – a new epidemic threat

    Directory of Open Access Journals (Sweden)

    Dominika Pomorska

    2016-06-01

    Full Text Available Zika virus, like dengue and yellow fever viruses, is an RNA virus of the Flaviviridae family. The virus is transmitted by Aedes mosquitoes. On February 1, 2016, the World Health Organization declared Zika virus a Public Health Emergency of International Concern, similarly as in the case of Ebola virus in 2014 and bird flu virus in 2009. Although the Zika virus commonly causes a mild flu-like illness, it can cause congenital infections in the foetus. Based on the recommendations of the International Health Regulations Emergency Committee, the World Health Organization confirmed the possible relationship between the increase in the incidence of Zika virus infections and an increased number of infants with microcephaly. The incidence of microcephaly in Brazil in 2015 was 10–20 times higher than in previous years. A total of 691 cases of travel-related Zika infections have been reported in the United States of America, including 206 pregnant women – with 11 cases of sexually transmitted infection; Guillain–Barré syndrome complication was identified in 2 cases. There is an emphasis on measures to prevent mosquito bites and eliminate mosquito breeding sites in the countries affected by the epidemic. Due to both, Zika virus isolation from sperm and the growing number of sexually transmitted infections, measures to prevent sexual transmission of Zika virus have also been taken. There is an ongoing research to develop vaccine against the Zika virus, however, the estimated time of vaccine development is several years.

  15. Prenatal brain MRI of fetuses with Zika virus infection

    Energy Technology Data Exchange (ETDEWEB)

    Guillemette-Artur, Prisca [Centre Hospitalier de Polynesie Francaise, Service de Radiologie, Pirae, Tahiti (Country Unknown); Besnard, Marianne [Centre Hospitalier de Polynesie Francaise, Service de Reanimation Neo-natale, Pirae, Tahiti (Country Unknown); Eyrolle-Guignot, Dominique [Centre Hospitalier de Polynesie Francaise, Service d' Obstetrique, Pirae, Tahiti (Country Unknown); Jouannic, Jean-Marie [Universite Pierre et Marie Curie, Service de Medecine Foetale, Hopital d' Enfants Armand-Trousseau, Paris (France); Garel, Catherine [Hopital d' Enfants Armand-Trousseau, Department of Radiology, Paris (France)

    2016-06-15

    An outbreak of Zika virus was observed in French Polynesia in 2013-2014. Maternal Zika virus infection has been associated with fetal microcephaly and severe cerebral damage. To analyze the MRI cerebral findings in fetuses with intrauterine Zika virus infection. We retrospectively analyzed prospectively collected data. Inclusion criteria comprised cases with (1) estimated conception date between June 2013 and May 2014, (2) available US and MRI scans revealing severe fetal brain lesions and (3) positive polymerase chain reaction for Zika virus in the amniotic fluid. We recorded pregnancy history of Zika virus infection and analyzed US and MRI scans. Three out of 12 cases of severe cerebral lesions fulfilled all inclusion criteria. History of maternal Zika virus infection had been documented in two cases. Calcifications and ventriculomegaly were present at US in all cases. MRI showed micrencephaly (n = 3), low cerebellar biometry (n = 2), occipital subependymal pseudocysts (n = 2), polymicrogyria with laminar necrosis and opercular dysplasia (n = 3), absent (n = 1) or hypoplastic (n = 1) corpus callosum and hypoplastic brainstem (n = 1). Severe cerebral damage was observed in our series, with indirect findings suggesting that the germinal matrix is the principal target for Zika virus. The lesions are very similar to severe forms of congenital cytomegalovirus and lymphocytic choriomeningitis virus infections. (orig.)

  16. Prenatal brain MRI of fetuses with Zika virus infection.

    Science.gov (United States)

    Guillemette-Artur, Prisca; Besnard, Marianne; Eyrolle-Guignot, Dominique; Jouannic, Jean-Marie; Garel, Catherine

    2016-06-01

    An outbreak of Zika virus was observed in French Polynesia in 2013-2014. Maternal Zika virus infection has been associated with fetal microcephaly and severe cerebral damage. To analyze the MRI cerebral findings in fetuses with intrauterine Zika virus infection. We retrospectively analyzed prospectively collected data. Inclusion criteria comprised cases with (1) estimated conception date between June 2013 and May 2014, (2) available US and MRI scans revealing severe fetal brain lesions and (3) positive polymerase chain reaction for Zika virus in the amniotic fluid. We recorded pregnancy history of Zika virus infection and analyzed US and MRI scans. Three out of 12 cases of severe cerebral lesions fulfilled all inclusion criteria. History of maternal Zika virus infection had been documented in two cases. Calcifications and ventriculomegaly were present at US in all cases. MRI showed micrencephaly (n = 3), low cerebellar biometry (n = 2), occipital subependymal pseudocysts (n = 2), polymicrogyria with laminar necrosis and opercular dysplasia (n = 3), absent (n = 1) or hypoplastic (n = 1) corpus callosum and hypoplastic brainstem (n = 1). Severe cerebral damage was observed in our series, with indirect findings suggesting that the germinal matrix is the principal target for Zika virus. The lesions are very similar to severe forms of congenital cytomegalovirus and lymphocytic choriomeningitis virus infections.

  17. Prenatal brain MRI of fetuses with Zika virus infection

    International Nuclear Information System (INIS)

    Guillemette-Artur, Prisca; Besnard, Marianne; Eyrolle-Guignot, Dominique; Jouannic, Jean-Marie; Garel, Catherine

    2016-01-01

    An outbreak of Zika virus was observed in French Polynesia in 2013-2014. Maternal Zika virus infection has been associated with fetal microcephaly and severe cerebral damage. To analyze the MRI cerebral findings in fetuses with intrauterine Zika virus infection. We retrospectively analyzed prospectively collected data. Inclusion criteria comprised cases with (1) estimated conception date between June 2013 and May 2014, (2) available US and MRI scans revealing severe fetal brain lesions and (3) positive polymerase chain reaction for Zika virus in the amniotic fluid. We recorded pregnancy history of Zika virus infection and analyzed US and MRI scans. Three out of 12 cases of severe cerebral lesions fulfilled all inclusion criteria. History of maternal Zika virus infection had been documented in two cases. Calcifications and ventriculomegaly were present at US in all cases. MRI showed micrencephaly (n = 3), low cerebellar biometry (n = 2), occipital subependymal pseudocysts (n = 2), polymicrogyria with laminar necrosis and opercular dysplasia (n = 3), absent (n = 1) or hypoplastic (n = 1) corpus callosum and hypoplastic brainstem (n = 1). Severe cerebral damage was observed in our series, with indirect findings suggesting that the germinal matrix is the principal target for Zika virus. The lesions are very similar to severe forms of congenital cytomegalovirus and lymphocytic choriomeningitis virus infections. (orig.)

  18. A Novel Type of Polyhedral Viruses Infecting Hyperthermophilic Archaea.

    Science.gov (United States)

    Liu, Ying; Ishino, Sonoko; Ishino, Yoshizumi; Pehau-Arnaudet, Gérard; Krupovic, Mart; Prangishvili, David

    2017-07-01

    Encapsidation of genetic material into polyhedral particles is one of the most common structural solutions employed by viruses infecting hosts in all three domains of life. Here, we describe a new virus of hyperthermophilic archaea, Sulfolobus polyhedral virus 1 (SPV1), which condenses its circular double-stranded DNA genome in a manner not previously observed for other known viruses. The genome complexed with virion proteins is wound up sinusoidally into a spherical coil which is surrounded by an envelope and further encased by an outer polyhedral capsid apparently composed of the 20-kDa virion protein. Lipids selectively acquired from the pool of host lipids are integral constituents of the virion. None of the major virion proteins of SPV1 show similarity to structural proteins of known viruses. However, minor structural proteins, which are predicted to mediate host recognition, are shared with other hyperthermophilic archaeal viruses infecting members of the order Sulfolobales The SPV1 genome consists of 20,222 bp and contains 45 open reading frames, only one-fifth of which could be functionally annotated. IMPORTANCE Viruses infecting hyperthermophilic archaea display a remarkable morphological diversity, often presenting architectural solutions not employed by known viruses of bacteria and eukaryotes. Here we present the isolation and characterization of Sulfolobus polyhedral virus 1, which condenses its genome into a unique spherical coil. Due to the original genomic and architectural features of SPV1, the virus should be considered a representative of a new viral family, "Portogloboviridae." Copyright © 2017 American Society for Microbiology.

  19. Infection and Replication of Influenza Virus at the Ocular Surface.

    Science.gov (United States)

    Creager, Hannah M; Kumar, Amrita; Zeng, Hui; Maines, Taronna R; Tumpey, Terrence M; Belser, Jessica A

    2018-04-01

    Although influenza viruses typically cause respiratory tract disease, some viruses, particularly those with an H7 hemagglutinin, have been isolated from the eyes of conjunctivitis cases. Previous work has shown that isolates of multiple subtypes from both ocular and respiratory infections are capable of replication in human ex vivo ocular tissues and corneal or conjunctival cell monolayers, leaving the determinants of ocular tropism unclear. Here, we evaluated the effect of several variables on tropism for ocular cells cultured in vitro and examined the potential effect of the tear film on viral infectivity. All viruses tested were able to replicate in primary human corneal epithelial cell monolayers subjected to aerosol inoculation. The temperature at which cells were cultured postinoculation minimally affected infectivity. Replication efficiency, in contrast, was reduced at 33°C relative to that at 37°C, and this effect was slightly greater for the conjunctivitis isolates than for the respiratory ones. With the exception of a seasonal H3N2 virus, the subset of viruses studied in multilayer corneal tissue constructs also replicated productively after either aerosol or liquid inoculation. Human tears significantly inhibited the hemagglutination of both ocular and nonocular isolates, but the effect on viral infectivity was more variable, with tears reducing the infectivity of nonocular isolates more than ocular isolates. These data suggest that most influenza viruses may be capable of establishing infection if they reach the surface of ocular cells but that this is more likely for ocular-tropic viruses, as they are better able to maintain their infectivity during passage through the tear film. IMPORTANCE The potential spread of zoonotic influenza viruses to humans represents an important threat to public health. Unfortunately, despite the importance of cellular and tissue tropism to pathogenesis, determinants of influenza virus tropism have yet to be fully

  20. Wolbachia and dengue virus infection in the mosquito Aedes fluviatilis (Diptera: Culicidae.

    Directory of Open Access Journals (Sweden)

    Jéssica Barreto Lopes Silva

    Full Text Available Dengue represents a serious threat to human health, with billions of people living at risk of the disease. Wolbachia pipientis is a bacterial endosymbiont common to many insect species. Wolbachia transinfections in mosquito disease vectors have great value for disease control given the bacterium's ability to spread into wild mosquito populations, and to interfere with infections of pathogens, such as dengue virus. Aedes fluviatilis is a mosquito with a widespread distribution in Latin America, but its status as a dengue vector has not been clarified. Ae. fluviatilis is also naturally infected by the wFlu Wolbachia strain, which has been demonstrated to enhance infection with the avian malarial parasite Plasmodium gallinaceum. We performed experimental infections of Ae. fluviatilis with DENV-2 and DENV-3 isolates from Brazil via injection or oral feeding to provide insight into its competence for the virus. We also examined the effect of the native Wolbachia infection on the virus using a mosquito line where the wFlu infection had been cleared by antibiotic treatment. Through RT-qPCR, we observed that Ae. fluviatilis could become infected with both viruses via either method of infection, although at a lower rate than Aedes aegypti, the primary dengue vector. We then detected DENV-2 and DENV-3 in the saliva of injected mosquitoes, and observed that injection of DENV-3-infected saliva produced subsequent infections in naïve Ae. aegypti. However, across our data we observed no difference in prevalence of infection and viral load between Wolbachia-infected and -uninfected mosquitoes, suggesting that there is no effect of wFlu on dengue virus. Our results highlight that Ae. fluviatilis could potentially serve as a dengue vector under the right circumstances, although further testing is required to determine if this occurs in the field.

  1. Increase of cells expressing PD-L1 in bovine leukemia virus infection and enhancement of anti-viral immune responses in vitro via PD-L1 blockade

    Directory of Open Access Journals (Sweden)

    Ikebuchi Ryoyo

    2011-09-01

    Full Text Available Abstract The inhibitory receptor programmed death-1 (PD-1 and its ligand, programmed death-ligand 1 (PD-L1 are involved in immune evasion mechanisms for several pathogens causing chronic infections. Blockade of the PD-1/PD-L1 pathway restores anti-virus immune responses, with concomitant reduction in viral load. In a previous report, we showed that, in bovine leukemia virus (BLV infection, the expression of bovine PD-1 is closely associated with disease progression. However, the functions of bovine PD-L1 are still unknown. To investigate the role of PD-L1 in BLV infection, we identified the bovine PD-L1 gene, and examined PD-L1 expression in BLV-infected cattle in comparison with uninfected cattle. The deduced amino acid sequence of bovine PD-L1 shows high homology to the human and mouse PD-L1. The proportion of PD-L1 positive cells, especially among B cells, was upregulated in cattle with the late stage of the disease compared to cattle at the aleukemic infection stage or uninfected cattle. The proportion of PD-L1 positive cells correlated positively with prediction markers for the progression of the disease such as leukocyte number, virus load and virus titer whilst on the contrary, it inversely correlated with the degree of interferon-gamma expression. Blockade of the PD-1/PD-L1 pathway in vitro by PD-L1-specific antibody upregulated the production of interleukin-2 and interferon-gamma, and correspondingly, downregulated the BLV provirus load and the proportion of BLV-gp51 expressing cells. These data suggest that PD-L1 induces immunoinhibition in disease progressed cattle during chronic BLV infection. Therefore, PD-L1 would be a potential target for developing immunotherapies against BLV infection.

  2. Euthanasia Assessment in Ebola Virus Infected Nonhuman Primates

    Directory of Open Access Journals (Sweden)

    Travis K. Warren

    2014-11-01

    Full Text Available Multiple products are being developed for use against filoviral infections. Efficacy for these products will likely be demonstrated in nonhuman primate models of filoviral disease to satisfy licensure requirements under the Animal Rule, or to supplement human data. Typically, the endpoint for efficacy assessment will be survival following challenge; however, there exists no standardized approach for assessing the health or euthanasia criteria for filovirus-exposed nonhuman primates. Consideration of objective criteria is important to (a ensure test subjects are euthanized without unnecessary distress; (b enhance the likelihood that animals exhibiting mild or moderate signs of disease are not prematurely euthanized; (c minimize the occurrence of spontaneous deaths and loss of end-stage samples; (d enhance the reproducibility of experiments between different researchers; and (e provide a defensible rationale for euthanasia decisions that withstands regulatory scrutiny. Historic records were compiled for 58 surviving and non-surviving monkeys exposed to Ebola virus at the US Army Medical Research Institute of Infectious Diseases. Clinical pathology parameters were statistically analyzed and those exhibiting predicative value for survival are reported. These findings may be useful for standardization of objective euthanasia assessments in rhesus monkeys exposed to Ebola virus and may serve as a useful approach for other standardization efforts.

  3. Immunological Control of Viral Infections in Bats and the Emergence of Viruses Highly Pathogenic to Humans

    Directory of Open Access Journals (Sweden)

    Tony Schountz

    2017-09-01

    Full Text Available Bats are reservoir hosts of many important viruses that cause substantial disease in humans, including coronaviruses, filoviruses, lyssaviruses, and henipaviruses. Other than the lyssaviruses, they do not appear to cause disease in the reservoir bats, thus an explanation for the dichotomous outcomes of infections of humans and bat reservoirs remains to be determined. Bats appear to have a few unusual features that may account for these differences, including evidence of constitutive interferon (IFN activation and greater combinatorial diversity in immunoglobulin genes that do not undergo substantial affinity maturation. We propose these features may, in part, account for why bats can host these viruses without disease and how they may contribute to the highly pathogenic nature of bat-borne viruses after spillover into humans. Because of the constitutive IFN activity, bat-borne viruses may be shed at low levels from bat cells. With large naive antibody repertoires, bats may control the limited virus replication without the need for rapid affinity maturation, and this may explain why bats typically have low antibody titers to viruses. However, because bat viruses have evolved in high IFN environments, they have enhanced countermeasures against the IFN response. Thus, upon infection of human cells, where the IFN response is not constitutive, the viruses overwhelm the IFN response, leading to abundant virus replication and pathology.

  4. Virus specific antigens in mammalian cells infected with herpes simplex virus

    Science.gov (United States)

    Watson, D. H.; Shedden, W. I. H.; Elliot, A.; Tetsuka, T.; Wildy, P.; Bourgaux-Ramoisy, D.; Gold, E.

    1966-01-01

    Antisera to specific proteins in herpes simplex infected cells were produced by immunization of rabbits with infected rabbit kidney cells. These antisera were highly virus specific and produced up to twelve lines in immunodiffusion tests against infected cell extracts. Acrylamide electrophoresis and immunoelectrophoresis revealed up to ten virus specific proteins of varying size. ImagesFIG. 1FIG. 2FIG. 3FIG. 4FIG. 5 PMID:4288648

  5. Seroprevalence of Ebola virus infection in Bombali District, Sierra Leone

    Directory of Open Access Journals (Sweden)

    Nadege Goumkwa Mafopa

    2017-12-01

    Full Text Available A serosurvey of anti-Ebola Zaire virus nucleoprotein IgG prevalence was carried out among Ebola virus disease survivors and their Community Contacts in Bombali District, Sierra Leone. Our data suggest that the specie of Ebola virus (Zaire responsible of the 2013-2016 epidemic in West Africa may cause mild or asymptomatic infection in a proportion of cases, possibly due to an efficient immune response.

  6. Virus and Infections 2010 - BIT's first world congress.

    Science.gov (United States)

    Garkavenko, Olga

    2010-10-01

    The World Congress of Virus and Infections, held in Busan, South Korea, included topics reviewing the field of zoonoses. This conference report highlights selected presentations on surveillance, epidemiology and measures for the control and prevention of zoonotic diseases. Topics discussed include human factors influencing zoonoses, the molecular epidemiology of Crimean-Congo hemorrhagic fever, the emerging Nipah virus, and the re-emergence of cowpox virus.

  7. NNDSS - Table II. Cryptosporidiosis to Dengue virus infection

    Data.gov (United States)

    U.S. Department of Health & Human Services — NNDSS - Table II. Cryptosporidiosis to Dengue virus infection - 2018. In this Table, provisional cases of selected notifiable diseases (≥1,000 cases reported during...

  8. Respiratory Syncytial Virus Infection (RSV): Transmission and Prevention

    Science.gov (United States)

    ... of Search Controls Search Form Controls Cancel Submit Respiratory Syncytial Virus Infection (RSV) Note: Javascript is disabled ... 2018 Content source: National Center for Immunization and Respiratory Diseases (NCIRD) , Division of Viral Diseases Email Recommend ...

  9. Schmallenberg virus infection of ruminants: challenges and opportunities for veterinarians

    Directory of Open Access Journals (Sweden)

    Claine F

    2015-06-01

    Full Text Available François Claine, Damien Coupeau, Laetitia Wiggers, Benoît Muylkens, Nathalie Kirschvink Veterinary Department, Faculty of Sciences, Namur Research Institute for Life Sciences (NARILIS, University of Namur (UNamur, Namur, Belgium Abstract: In 2011, European ruminant flocks were infected by Schmallenberg virus (SBV leading to transient disease in adult cattle but abortions and congenital deformities in calves, lambs, and goat kids. SBV belonging to the Simbu serogroup (family Bunyaviridae and genus Orthobunyavirus was first discovered in the same region where bluetongue virus serotype 8 (BTV-8 emerged 5 years before. Both viruses are transmitted by biting midges (Culicoides spp. and share several similarities. This paper describes the current knowledge of temporal and geographical spread, molecular virology, transmission and susceptible species, clinical signs, diagnosis, prevention and control, impact on ruminant health, and productivity of SBV infection in Europe, and compares SBV infection with BTV-8 infection in ruminants. Keywords: Schmallenberg virus, Europe, ruminants, review

  10. Protection of melon plants against Cucumber mosaic virus infection ...

    African Journals Online (AJOL)

    Adhab

    The broad host range of CMV and its ability to be transmitted by aphids .... development of obvious yellow color in ELISA micro plate wells. The mean ... hosts harbor the virus in asymptomatic infection (Table. 1). ... Aster subulatus Michx.

  11. Easy and Rapid Detection of Mumps Virus by Live Fluorescent Visualization of Virus-Infected Cells.

    Directory of Open Access Journals (Sweden)

    Tadanobu Takahashi

    Full Text Available Mumps viruses show diverse cytopathic effects (CPEs of infected cells and viral plaque formation (no CPE or no plaque formation in some cases depending on the viral strain, highlighting the difficulty in mumps laboratory studies. In our previous study, a new sialidase substrate, 2-(benzothiazol-2-yl-4-bromophenyl 5-acetamido-3,5-dideoxy-α-D-glycero-D-galacto-2-nonulopyranosidonic acid (BTP3-Neu5Ac, was developed for visualization of sialidase activity. BTP3-Neu5Ac can easily and rapidly perform histochemical fluorescent visualization of influenza viruses and virus-infected cells without an antiviral antibody and cell fixation. In the present study, the potential utility of BTP3-Neu5Ac for rapid detection of mumps virus was demonstrated. BTP3-Neu5Ac could visualize dot-blotted mumps virus, virus-infected cells, and plaques (plaques should be called focuses due to staining of infected cells in this study, even if a CPE was not observed. Furthermore, virus cultivation was possible by direct pick-up from a fluorescent focus. In conventional methods, visible appearance of the CPE and focuses often requires more than 6 days after infection, but the new method with BTP3-Neu5Ac clearly visualized infected cells after 2 days and focuses after 4 days. The BTP3-Neu5Ac assay is a precise, easy, and rapid assay for confirmation and titration of mumps virus.

  12. Herpes Simplex Virus type 2 Infection among Females in Enugu ...

    African Journals Online (AJOL)

    Herpes simplex virus type 2 has recently been found to have synergistic effect with human immunodeficiency virus (HIV) and co-infection of the two presents more severe burden to the immunity of the victim. This leads to much morbidity and mortality with negative economic impact. In this study, we set out to determine ...

  13. Vaccinia Virus Infections in a Martial Arts Gym

    Centers for Disease Control (CDC) Podcasts

    This podcast discusses an outbreak of vaccinia virus in Maryland in 2008. Christine Hughes, a health scientist with the Poxvirus and Rabies Branch at CDC, and co-author of a paper in the April 2011 issue of CDC's journal, discusses vaccinia virus infections in a martial arts gym.

  14. Viral protein synthesis in cowpea mosaic virus infected protoplasts

    NARCIS (Netherlands)

    Rottier, P.

    1980-01-01

    In contrast to the situation concerning bacterial and, to a lesser extent, animal RNA viruses, little is known about the biochemical processes occurring in plant cells due to plant RNA virus infection. Such processes are difficult to study using intact plants or leaves. Great effort has

  15. Proteins synthesized in tobacco mosaic virus infected protoplasts

    NARCIS (Netherlands)

    Huber, R.

    1979-01-01

    The study described here concerns the proteins, synthesized as a result of tobacco mosaic virus (TMV) multiplication in tobacco protoplasts and in cowpea protoplasts. The identification of proteins involved in the TMV infection, for instance in the virus RNA replication, helps to elucidate

  16. Varicella-zoster virus (chickenpox) infection in pregnancy

    DEFF Research Database (Denmark)

    Lamont, Ronald F; Sobel, Jack D; Carrington, D

    2011-01-01

    Please cite this paper as: Lamont R, Sobel J, Carrington D, Mazaki-Tovi S, Kusanovic J, Vaisbuch E, Romero R. Varicella-zoster virus (chickenpox) infection in pregnancy. BJOG 2011; DOI: 10.1111/j.1471-0528.2011.02983.x. Congenital varicella syndrome, maternal varicella-zoster virus pneumonia and ...

  17. Measles vaccination of nonhuman primates provides partial protection against infection with canine distemper virus.

    Science.gov (United States)

    de Vries, Rory D; Ludlow, Martin; Verburgh, R Joyce; van Amerongen, Geert; Yüksel, Selma; Nguyen, D Tien; McQuaid, Stephen; Osterhaus, Albert D M E; Duprex, W Paul; de Swart, Rik L

    2014-04-01

    Measles virus (MV) is being considered for global eradication, which would likely reduce compliance with MV vaccination. As a result, children will grow up without MV-specific immunity, creating a potential niche for closely related animal morbilliviruses such as canine distemper virus (CDV). Natural CDV infection causing clinical signs has never been reported in humans, but recent outbreaks in captive macaques have shown that CDV can cause disease in primates. We studied the virulence and tropism of recombinant CDV expressing enhanced green fluorescent protein in naive and measles-vaccinated cynomolgus macaques. In naive animals CDV caused viremia and fever and predominantly infected CD150(+) lymphocytes and dendritic cells. Virus was reisolated from the upper and lower respiratory tracts, but infection of epithelial or neuronal cells was not detectable at the time points examined, and the infections were self-limiting. This demonstrates that CDV readily infects nonhuman primates but suggests that additional mutations are necessary to achieve full virulence in nonnatural hosts. Partial protection against CDV was observed in measles-vaccinated macaques, as demonstrated by accelerated control of virus replication and limited shedding from the upper respiratory tract. While neither CDV infection nor MV vaccination induced detectable cross-reactive neutralizing antibodies, MV-specific neutralizing antibody levels of MV-vaccinated macaques were boosted by CDV challenge infection, suggesting that cross-reactive VN epitopes exist. Rapid increases in white blood cell counts in MV-vaccinated macaques following CDV challenge suggested that cross-reactive cellular immune responses were also present. This study demonstrates that zoonotic morbillivirus infections can be controlled by measles vaccination. Throughout history viral zoonoses have had a substantial impact on human health. Given the drive toward global eradication of measles, it is essential to understand the

  18. Background review for diagnostic test development for Zika virus infection.

    Science.gov (United States)

    Charrel, Rémi N; Leparc-Goffart, Isabelle; Pas, Suzan; de Lamballerie, Xavier; Koopmans, Marion; Reusken, Chantal

    2016-08-01

    To review the state of knowledge about diagnostic testing for Zika virus infection and identify areas of research needed to address the current gaps in knowledge. We made a non-systematic review of the published literature about Zika virus and supplemented this with information from commercial diagnostic test kits and personal communications with researchers in European preparedness networks. The review covered current knowledge about the geographical spread, pathogen characteristics, life cycle and infection kinetics of the virus. The available molecular and serological tests and biosafety issues are described and discussed in the context of the current outbreak strain. We identified the following areas of research to address current knowledge gaps: (i) an urgent assessment of the laboratory capacity and capability of countries to detect Zika virus; (ii) rapid and extensive field validation of the available molecular and serological tests in areas with and without Zika virus transmission, with a focus on pregnant women; (iii) monitoring the genomic diversity of circulating Zika virus strains; (iv) prospective studies into the virus infection kinetics, focusing on diagnostic sampling (specimen types, combinations and timings); and (v) developing external quality assessments for molecular and serological testing, including differential diagnosis for similar viruses and symptom clusters. The availability of reagents for diagnostic development (virus strains and antigens, quantified viral ribonucleic acid) needs to be facilitated. An international laboratory response is needed, including preparation of protocols for prospective studies to address the most pressing information needs.

  19. TNF-Overexpression in Borna Disease Virus-Infected Mouse Brains Triggers Inflammatory Reaction and Epileptic Seizures

    NARCIS (Netherlands)

    Kramer, Katharina; Schaudien, Dirk; Eisel, Ulrich L. M.; Herzog, Sibylle; Richt, Juergen A.; Baumgaertner, Wolfgang; Herden, Christiane

    2012-01-01

    Proinflammatory state of the brain increases the risk for seizure development. Neonatal Borna disease virus (BDV)-infection of mice with neuronal overexpression of tumor necrosis factor-alpha (TNF) was used to investigate the complex relationship between enhanced cytokine levels, neurotropic virus

  20. Mitigating Prenatal Zika Virus Infection in the Americas.

    Science.gov (United States)

    Ndeffo-Mbah, Martial L; Parpia, Alyssa S; Galvani, Alison P

    2016-10-18

    Because of the risk for Zika virus infection in the Americas and the links between infection and microcephaly, other serious neurologic conditions, and fetal death, health ministries across the region have advised women to delay pregnancy. However, the effectiveness of this policy in reducing prenatal Zika virus infection has yet to be quantified. To evaluate the effectiveness of pregnancy-delay policies on the incidence and prevalence of prenatal Zika virus infection. Vector-borne Zika virus transmission model fitted to epidemiologic data from 2015 to 2016 on Zika virus infection in Colombia. Colombia, August 2015 to July 2017. Population of Colombia, stratified by sex, age, and pregnancy status. Recommendations to delay pregnancy by 3, 6, 9, 12, or 24 months, at different levels of adherence. Weekly and cumulative incidence of prenatal infections and microcephaly cases. With 50% adherence to recommendations to delay pregnancy by 9 to 24 months, the cumulative incidence of prenatal Zika virus infections is likely to decrease by 17% to 44%, whereas recommendations to delay pregnancy by 6 or fewer months are likely to increase prenatal infections by 2% to 7%. This paradoxical exacerbation of prenatal Zika virus exposure is due to an elevated risk for pregnancies to shift toward the peak of the outbreak. Sexual transmission was not explicitly accounted for in the model because of limited data but was implicitly subsumed within the overall transmission rate, which was calibrated to observed incidence. Pregnancy delays can have a substantial effect on reducing cases of microcephaly but risks exacerbating the Zika virus outbreak if the duration is not sufficient. Duration of the delay, population adherence, and the timing of initiation of the intervention must be carefully considered. National Institutes of Health.

  1. Serious invasive Saffold virus infections in children, 2009

    DEFF Research Database (Denmark)

    Nielsen, Alex Christian Yde; Böttiger, Blenda; Banner, Jytte

    2012-01-01

    The first human virus in the genus Cardiovirus was described in 2007 and named Saffold virus (SAFV). Cardioviruses can cause severe infections of the myocardium and central nervous system in animals, but SAFV has not yet been convincingly associated with disease in humans. To study a possible ass...... association between SAFV and infections in the human central nervous system, we designed a real-time PCR for SAFV and tested cerebrospinal fluid (CSF) samples from children...

  2. Human papilloma virus infection and cervical dysplasia.

    Science.gov (United States)

    Melinte-Popescu, Alina; Costăchescu, Gh

    2012-01-01

    Pap testing is considered to be the best screening tool for cervical cancer but there is currently great interest in the possible application of human papilloma virus (HPV) testing to supplement Pap screening for cervical cancer. To determine the prevalence of high-risk HPV types in the studied population and to explore the association between high-risk HPV types and cervical dysplasia. Cross-sectional study conducted at the Iasi Cuza Voda Obstetrics-Gynecology Hospital and Suceava County Hospital. 332 women who underwent colposcopy for cervical lesions between 2006 and 2011 were included in this study. The overall prevalence of HPV was 57.23%. HPV prevalence differs significantly in the three age groups up to 50 years. It was highest in patients below the age of 40 and progressively lower with advancing age. The overall prevalence of cervical dysplasia was 56.62%. The prevalence of cervical dysplasia was highest in the age groups up to 40 years. The most important determinant of HPV infection is age. Persistence of HPV appears to be associated with progression to squamous intraepithelial lesion. Dysplasia is often missed in a cervical sample either because of human error in screening and interpretation, or because of suboptimal quality of Pap smear. Incorporation of HPV testing into the present Pap screening program has the potential of making screening for cervical cancer more effective, and a necessary prelude to assessing this is by determining the prevalence of the high-risk types.

  3. Decreasing seroprevalence of herpes simplex virus type 1 and type 2 in Germany leaves many people susceptible to genital infection: time to raise awareness and enhance control.

    Science.gov (United States)

    Korr, Gerit; Thamm, Michael; Czogiel, Irina; Poethko-Mueller, Christina; Bremer, Viviane; Jansen, Klaus

    2017-07-06

    Herpes simplex infections (HSV1/2) are characterized by recurrent symptoms, a risk of neonatal herpes, and the facilitation of HIV transmission. In Germany, HSV1/2 infections are not notifiable and data are scarce. A previous study found higher HSV1/2 seroprevalences in women in East Germany than in women in West Germany. We assessed changes in the HSV1/2 seroprevalences over time and investigated determinants associated with HSV1/2 seropositivity to guide prevention and control. The study was based on the German Health Interview and Examination Survey for Adults (DEGS; 2008-2011) and the German National Health Interview and Examination Survey (GNHIES; 1997-1999). We tested serum samples from DEGS participants for HSV1 and HSV2 immunoglobulin G. We used Pearson's χ 2 test to compare the HSV1/HSV2 seroprevalences in terms of sex, age, and region of residence (East/West Germany) and investigated potential determinants by calculating prevalence ratios (PR) with log-binomial regression. All statistical analyses included survey weights. In total, 6627 DEGS participants were tested for HSV1, and 5013 were also tested for HSV2. Overall, HSV1 seroprevalence decreased significantly from 1997-1999 (82.1%; 95%CI 80.6-83.6) to 2008-2011 (78.4%; 95%CI 77.8-79.7). In the same period, overall HSV2 seroprevalence decreased significantly from 13.3% (95%CI 11.9-14.9) to 9.6% (95%CI 8.6-10.8), notably in 18-24-year-old men (10.4 to 0%) in East Germany. Women were more likely than men to be seropositive for HSV1 (PR 1.1) or HSV2 (PR 1.6). A lower level of education, smoking, and not speaking German were associated with HSV1 in both sexes. Women of older age, who smoked, or had a history of abortion and men of older age or who had not attended a nursery school during childhood were more often seropositive for HSV2. The reduced seroprevalences of HSV1 and HSV2 leave more people susceptible to genital HSV1/2 infections. Practitioners should be aware of HSV infection as a differential

  4. Autophagy in Negative-Strand RNA Virus Infection

    Directory of Open Access Journals (Sweden)

    Yupeng Wang

    2018-02-01

    Full Text Available Autophagy is a homoeostatic process by which cytoplasmic material is targeted for degradation by the cell. Viruses have learned to manipulate the autophagic pathway to ensure their own replication and survival. Although much progress has been achieved in dissecting the interplay between viruses and cellular autophagic machinery, it is not well understood how the cellular autophagic pathway is utilized by viruses and manipulated to their own advantage. In this review, we briefly introduce autophagy, viral xenophagy and the interaction among autophagy, virus and immune response, then focus on the interplay between NS-RNA viruses and autophagy during virus infection. We have selected some exemplary NS-RNA viruses and will describe how these NS-RNA viruses regulate autophagy and the role of autophagy in NS-RNA viral replication and in immune responses to virus infection. We also review recent advances in understanding how NS-RNA viral proteins perturb autophagy and how autophagy-related proteins contribute to NS-RNA virus replication, pathogenesis and antiviral immunity.

  5. Infection of Mosquito Cells (C6/36) by Dengue-2 Virus Interferes with Subsequent Infection by Yellow Fever Virus.

    Science.gov (United States)

    Abrao, Emiliana Pereira; da Fonseca, Benedito Antônio Lopes

    2016-02-01

    Dengue is one of the most important diseases caused by arboviruses in the world. Yellow fever is another arthropod-borne disease of great importance to public health that is endemic to tropical regions of Africa and the Americas. Both yellow fever and dengue viruses are flaviviruses transmitted by Aedes aegypti mosquitoes, and then, it is reasonable to consider that in a given moment, mosquito cells could be coinfected by both viruses. Therefore, we decided to evaluate if sequential infections of dengue and yellow fever viruses (and vice-versa) in mosquito cells could affect the virus replication patterns. Using immunofluorescence and real-time PCR-based replication assays in Aedes albopictus C6/36 cells with single or sequential infections with both viruses, we demonstrated the occurrence of viral interference, also called superinfection exclusion, between these two viruses. Our results show that this interference pattern is particularly evident when cells were first infected with dengue virus and subsequently with yellow fever virus (YFV). Reduction in dengue virus replication, although to a lower extent, was also observed when C6/36 cells were initially infected with YFV followed by dengue virus infection. Although the importance that these findings have on nature is unknown, this study provides evidence, at the cellular level, of the occurrence of replication interference between dengue and yellow fever viruses and raises the question if superinfection exclusion could be a possible explanation, at least partially, for the reported lack of urban yellow fever occurrence in regions where a high level of dengue transmission occurs.

  6. Comparative Pathology of Hepatitis A Virus and Hepatitis E Virus Infection.

    Science.gov (United States)

    Cullen, John M; Lemon, Stanley M

    2018-04-30

    Hepatitis A virus (HAV) and hepatitis E virus (HEV) cause acute, self-limiting hepatic infections that are usually spread by the fecal-oral route in humans. Naturally occurring and experimental infections are possible in a variety of nonhuman primates and, in the case of HEV, a number of other species. Many advances in understanding the pathogenesis of these viruses have come from studies in experimental animals. In general, animals infected with these viruses recapitulate the histologic lesions seen in infected humans, but typically with less severe clinical and histopathological manifestations. This review describes the histopathologic changes associated with HAV and HEV infection in humans and experimental animals. Copyright © 2018 Cold Spring Harbor Laboratory Press; all rights reserved.

  7. Investigation of radiation enhanced reactivation of cytoplasmic replicating human virus

    International Nuclear Information System (INIS)

    Bockstahler, L.E.; Haynes, K.F.; Stafford, J.E.

    1976-01-01

    When monolayers of CV-1 monkey kidney cells were exposed to ultraviolet (uv) radiation (0 to 200 erg/nm 2 ) or x rays (0 to 10 krads) before infection with uv-irradiated herpes simplex virus, an increase in the infectivity of this nuclear replicating virus occurred as measured by plaque formation. These phenomena are known as uv (Weigle) reactivation (WR) and x-ray reactivation (x-ray R). In this study the presence of WR and x-ray R was examined in CV-1 cells infected with uv-irradiated vaccinia virus or poliovirus, both cytoplasmic replicating viruses. Little or no WR or x-ray R was observed for either of these viruses. These results suggest that WR and x-ray R in mammalian cells may be restricted to viruses which are synthesized in the cell nucleus

  8. UV radiation and mouse models of herpes simplex virus infection

    International Nuclear Information System (INIS)

    Norval, Mary; El-Ghorr, A.A.

    1996-01-01

    Orolabial human infections with herpes simplex virus type 1 (HSV-1) are very common; following the primary epidermal infection, the virus is retained in a latent form in the trigeminal ganglia from where it can reactivate and cause a recrudescent lesion. Recrudescences are triggered by various stimuli including exposure to sunlight. In this review three categories of mouse models are used to examine the effects of UV irradiation on HSV infections: these are UV exposure prior to primary infection, UV exposure as a triggering event for recrudescence and UV exposure prior to challenge with virus is mice already immunized to HSV. In each of these models immunosuppression occurs, which is manifest, in some instances, in increased morbidity or an increased rate of recrudescence. Where known, the immunological mechanisms involved in the models are summarized and their relevance to human infections considered. (Author)

  9. Microwave therapy for cutaneous human papilloma virus infection.

    Science.gov (United States)

    Bristow, Ivan; Lim, Wen Chean; Lee, Alvin; Holbrook, Daniel; Savelyeva, Natalia; Thomson, Peter; Webb, Christopher; Polak, Marta; Ardern-Jones, Michael R

    2017-10-01

    Human papilloma virus (HPV) infects keratinocytes of the skin and mucous membranes, and is associated with the induction of cutaneous warts and malignancy. Warts can induce significant morbidity and disability but most therapies, including cryotherapy, laser, and radiofrequency devices show low efficacy and induce discomfort through tissue destruction. Microwaves are readily capable of passing through highly keratinised skin to deliver energy and induce heating of the tissue in a highly controllable, uniform manner. To determine the effects of microwave on cutaneous HPV infection. We undertook a pilot study of microwave therapy to the skin in 32 consecutive individuals with 52 recalcitrant long-lived viral cutaneous warts. Additionally, we undertook a molecular characterisation of the effects of microwaves on the skin. Tissue inflammation was minimal, but 75.9% of lesions cleared which compares favourably with previous studies showing a clearance rate of 23-33% for cryotherapy or salicylic acid. We show that microwaves specifically induce dendritic cell cross-presentation of HPV antigen to CD8+ T cells and suggest that IL-6 may be important for DC IRF1 and IRF4 modulation to enhance this process. Keratinocyte-skin dendritic cell cross-talk is integral to host defence against HPV infections, and this pilot study supports the concept of microwave induction of anti-HPV immunity which offers a promising approach for treatment of HPV-induced viral warts and potentially HPV-related cancers.

  10. Canine distemper virus infection in a lesser grison (Galictis cuja: first report and virus phylogeny

    Directory of Open Access Journals (Sweden)

    Jane Megid

    2013-02-01

    Full Text Available Infectious diseases in wild animals have been increasing as a result of their habitat alterations and closer contact with domestic animals. Canine distemper virus (CDV has been reported in several species of wild carnivores, presenting a threat to wildlife conservation. We described the first case of canine distemper virus infection in lesser grison (Galictis cuja. A free-ranging individual, with no visible clinical sigs, presented sudden death after one day in captivity. Molecular diagnosis for CDV infection was performed using whole blood collected by postmortem intracardiac puncture, which resulted positive. The virus phylogeny indicated that domestic dogs were the probable source of infection.

  11. Chinese sacbrood virus infection in Asian honey bees (Apis cerana cerana) and host immune responses to the virus infection

    Science.gov (United States)

    Chinese Sacbrood virus (CSBV) is a common honey bee virus that infects both the European honey bee (A. mellifera) and the Asian honey bee (A. cerana). However, CSBV has much more devastating effects on Asian honey bees than on European honey bees, posing a serious threat to the agricultural and nat...

  12. Effects of acute respiratory virus infection upon tracheal mucous transport

    International Nuclear Information System (INIS)

    Gerrard, C.S.; Levandowski, R.A.; Gerrity, T.R.; Yeates, D.B.; Klein, E.

    1985-01-01

    Tracheal mucous velocity was measured in 13 healthy non-smokers using an aerosol labelled with /sup 99m/Tc and a multidetector probe during respiratory virus infections. The movement of boluses of tracheal mucous were either absent or reduced in number in five subjects with myxovirus infection (four influenza and one respiratory syncytial virus) within 48 hr of the onset of symptoms and in four subjects 1 wk later. One subject with influenza still had reduced bolus formation 12-16 wk after infection. Frequent coughing was a feature of those subjects with absent tracheal boluses. In contrast, four subjects with rhinovirus infection had normal tracheal mucous velocity at 48 hr after the onset of symptoms (4.1 +/- 1.3 mm/min). Tracheal mucous velocity was also normal (4.6 +/- 1.1 mm/min) in four subjects in whom no specific viral agent could be defined but had typical symptomatology of respiratory viral infection. During health tracheal mucous velocity was normal (4.8 +/- 1.6 mm/min) in the eleven subjects who had measurements made. Disturbances in tracheal mucous transport during virus infection appear to depend upon the type of virus and are most severe in influenza A and respiratory syncytial virus infection

  13. T-cell Responses in Individuals Infected with Zika Virus and in Those Vaccinated Against Dengue Virus

    Directory of Open Access Journals (Sweden)

    Dominic Paquin-Proulx

    2017-06-01

    Full Text Available Background: The outbreak of Zika virus (ZIKV infection in Brazil has raised concerns that infection during pregnancy could cause microcephaly and other severe neurodevelopmental malformations in the fetus. The mechanisms by which ZIKV causes fetal abnormalities are largely unknown. The importance of pre-infection with dengue virus (DENV, or other flaviviruses endemic to Brazil, remains to be investigated. It has been reported that antibodies directed against DENV can increase ZIKV infectivity by antibody dependent enhancement (ADE, suggesting that a history of prior DENV infection might worsen the outcome of ZIKV infection. Methods: We used bioinformatics tools to design 18 peptides from the ZIKV envelope containing predicted HLA-I T-cell epitopes and investigated T-cell cross-reactivity between ZIKV-infected individuals and DENV-vaccinated subjects by IFNg ELISPOT. Results: Three peptides induced IFNg production in both ZIKV-infected subjects and in DENV-vaccinated individuals. Flow cytometry indicated that 1 ZIKV peptide induced a CD4+ T-cell response in DENV-vaccinated subjects. Conclusions: We demonstrated that vaccination against DENV induced a T-cell response against ZIKV and identified one such CD4+ T-cell epitope. The ZIKV-reactive CD4+ T cells induced by DENV vaccination and identified in this study could contribute to the appearance of cross-reactive antibodies mediating ADE.

  14. T-cell Responses in Individuals Infected with Zika Virus and in Those Vaccinated Against Dengue Virus.

    Science.gov (United States)

    Paquin-Proulx, Dominic; Leal, Fabio E; Terrassani Silveira, Cassia G; Maestri, Alvino; Brockmeyer, Claudia; Kitchen, Shannon M; Cabido, Vinicius D; Kallas, Esper G; Nixon, Douglas F

    2017-01-01

    The outbreak of Zika virus (ZIKV) infection in Brazil has raised concerns that infection during pregnancy could cause microcephaly and other severe neurodevelopmental malformations in the fetus. The mechanisms by which ZIKV causes fetal abnormalities are largely unknown. The importance of pre-infection with dengue virus (DENV), or other flaviviruses endemic to Brazil, remains to be investigated. It has been reported that antibodies directed against DENV can increase ZIKV infectivity by antibody dependent enhancement (ADE), suggesting that a history of prior DENV infection might worsen the outcome of ZIKV infection. We used bioinformatics tools to design 18 peptides from the ZIKV envelope containing predicted HLA-I T-cell epitopes and investigated T-cell cross-reactivity between ZIKV-infected individuals and DENV-vaccinated subjects by IFNγ ELISPOT. Three peptides induced IFNγ production in both ZIKV-infected subjects and in DENV-vaccinated individuals. Flow cytometry indicated that 1 ZIKV peptide induced a CD4+ T-cell response in DENV-vaccinated subjects. We demonstrated that vaccination against DENV induced a T-cell response against ZIKV and identified one such CD4+ T-cell epitope. The ZIKV-reactive CD4+ T cells induced by DENV vaccination and identified in this study could contribute to the appearance of cross-reactive antibodies mediating ADE.

  15. The Aedes aegypti toll pathway controls dengue virus infection.

    Directory of Open Access Journals (Sweden)

    Zhiyong Xi

    2008-07-01

    Full Text Available Aedes aegypti, the mosquito vector of dengue viruses, utilizes its innate immune system to ward off a variety of pathogens, some of which can cause disease in humans. To date, the features of insects' innate immune defenses against viruses have mainly been studied in the fruit fly Drosophila melanogaster, which appears to utilize different immune pathways against different types of viruses, in addition to an RNA interference-based defense system. We have used the recently released whole-genome sequence of the Ae. aegypti mosquito, in combination with high-throughput gene expression and RNA interference (RNAi-based reverse genetic analyses, to characterize its response to dengue virus infection in different body compartments. We have further addressed the impact of the mosquito's endogenous microbial flora on virus infection. Our findings indicate a significant role for the Toll pathway in regulating resistance to dengue virus, as indicated by an infection-responsive regulation and functional assessment of several Toll pathway-associated genes. We have also shown that the mosquito's natural microbiota play a role in modulating the dengue virus infection, possibly through basal-level stimulation of the Toll immune pathway.

  16. Alarming incidence of hepatitis C virus re-infection after treatment of sexually acquired acute hepatitis C virus infection in HIV-infected MSM

    NARCIS (Netherlands)

    Lambers, Femke A. E.; Prins, Maria; Thomas, Xiomara; Molenkamp, Richard; Kwa, David; Brinkman, Kees; van der Meer, Jan T. M.; Schinkel, Janke; Countinho, R.; Reesink, H.; van Baarle, D.; Smit, C.; Gras, L.; van der Veldt, W.

    2011-01-01

    Recent data indicate that seroprevalence of sexually transmitted hepatitis C virus (HCV) infection among MSM is stabilizing in Amsterdam. However, little is known about the incidence of HCV re-infection in MSM who have cleared their HCV infection. We, therefore, studied the incidence of re-infection

  17. Virus Infection of Plants Alters Pollinator Preference: A Payback for Susceptible Hosts?

    Science.gov (United States)

    Davey, Matthew P.; Bruce, Toby J. A.; Caulfield, John C.; Furzer, Oliver J.; Reed, Alison; Robinson, Sophie I.; Miller, Elizabeth; Davis, Christopher N.; Pickett, John A.; Whitney, Heather M.; Glover, Beverley J.; Carr, John P.

    2016-01-01

    Plant volatiles play important roles in attraction of certain pollinators and in host location by herbivorous insects. Virus infection induces changes in plant volatile emission profiles, and this can make plants more attractive to insect herbivores, such as aphids, that act as viral vectors. However, it is unknown if virus-induced alterations in volatile production affect plant-pollinator interactions. We found that volatiles emitted by cucumber mosaic virus (CMV)-infected tomato (Solanum lycopersicum) and Arabidopsis thaliana plants altered the foraging behaviour of bumblebees (Bombus terrestris). Virus-induced quantitative and qualitative changes in blends of volatile organic compounds emitted by tomato plants were identified by gas chromatography-coupled mass spectrometry. Experiments with a CMV mutant unable to express the 2b RNA silencing suppressor protein and with Arabidopsis silencing mutants implicate microRNAs in regulating emission of pollinator-perceivable volatiles. In tomato, CMV infection made plants emit volatiles attractive to bumblebees. Bumblebees pollinate tomato by ‘buzzing’ (sonicating) the flowers, which releases pollen and enhances self-fertilization and seed production as well as pollen export. Without buzz-pollination, CMV infection decreased seed yield, but when flowers of mock-inoculated and CMV-infected plants were buzz-pollinated, the increased seed yield for CMV-infected plants was similar to that for mock-inoculated plants. Increased pollinator preference can potentially increase plant reproductive success in two ways: i) as female parents, by increasing the probability that ovules are fertilized; ii) as male parents, by increasing pollen export. Mathematical modeling suggested that over a wide range of conditions in the wild, these increases to the number of offspring of infected susceptible plants resulting from increased pollinator preference could outweigh underlying strong selection pressures favoring pathogen resistance

  18. Virus Infection of Plants Alters Pollinator Preference: A Payback for Susceptible Hosts?

    Directory of Open Access Journals (Sweden)

    Simon C Groen

    2016-08-01

    Full Text Available Plant volatiles play important roles in attraction of certain pollinators and in host location by herbivorous insects. Virus infection induces changes in plant volatile emission profiles, and this can make plants more attractive to insect herbivores, such as aphids, that act as viral vectors. However, it is unknown if virus-induced alterations in volatile production affect plant-pollinator interactions. We found that volatiles emitted by cucumber mosaic virus (CMV-infected tomato (Solanum lycopersicum and Arabidopsis thaliana plants altered the foraging behaviour of bumblebees (Bombus terrestris. Virus-induced quantitative and qualitative changes in blends of volatile organic compounds emitted by tomato plants were identified by gas chromatography-coupled mass spectrometry. Experiments with a CMV mutant unable to express the 2b RNA silencing suppressor protein and with Arabidopsis silencing mutants implicate microRNAs in regulating emission of pollinator-perceivable volatiles. In tomato, CMV infection made plants emit volatiles attractive to bumblebees. Bumblebees pollinate tomato by 'buzzing' (sonicating the flowers, which releases pollen and enhances self-fertilization and seed production as well as pollen export. Without buzz-pollination, CMV infection decreased seed yield, but when flowers of mock-inoculated and CMV-infected plants were buzz-pollinated, the increased seed yield for CMV-infected plants was similar to that for mock-inoculated plants. Increased pollinator preference can potentially increase plant reproductive success in two ways: i as female parents, by increasing the probability that ovules are fertilized; ii as male parents, by increasing pollen export. Mathematical modeling suggested that over a wide range of conditions in the wild, these increases to the number of offspring of infected susceptible plants resulting from increased pollinator preference could outweigh underlying strong selection pressures favoring pathogen

  19. Infection and Proliferation of Giant Viruses in Amoeba Cells.

    Science.gov (United States)

    Takemura, Masaharu

    2016-01-01

    Acanthamoeba polyphaga mimivirus, the first discovered giant virus with genome size and particle size much larger than previously discovered viruses, possesses several genes for translation and CRISPER Cas system-like defense mechanism against virophages, which co-infect amoeba cells with the giant virus and which inhibit giant virus proliferation. Mimiviruses infect amoeba cells by phagocytosis and release their DNA into amoeba cytoplasm through their stargate structure. After infection, giant virion factories (VFs) form in amoeba cytoplasm, followed by DNA replication and particle formation at peripheral regions of VF. Marseilleviruses, the smallest giant viruses, infect amoeba cells by phagocytosis or endocytosis, form larger VF than Mimivirus's VF in amoeba cytoplasm, and replicate their particles. Pandoraviruses found in 2013 have the largest genome size and particle size among all viruses ever found. Pandoraviruses infect amoeba cells by phagocytosis and release their DNA into amoeba cytoplasm through their mouth-like apical pores. The proliferation of Pandoraviruses occurs along with nucleus disruption. New virions form at the periphery of the region formerly occupied by the amoeba cell nucleus.

  20. Effects of interferon on cultured cells persistently infected with viruses

    Energy Technology Data Exchange (ETDEWEB)

    Crespi, M

    1986-01-01

    The role of interferon (IFN) in viral persistence at the cellular level was investigated. Two types of persistent infections were chosen. The first type was cell lines which contained hepatitis B virus (HBV) DNA (PLC/PRF/5 and Hep 3B cells) uninfected control hepatoma cells, (Mahlavu, HA22T and Hep G2 cells) or simian virus 40 (SV40) DNA (C2, C6, C11 cells) and control uninfected (CV-1 cells). In the second type of infection Vero cells persistently infected with SSPE or Sendai virus were used. The aim of this work was to determine what effect IFN had in these infections in terms of its antiviral and antiproliferative effects; which of the two major IFN-induced pathways, E enzyme or protein kinase were induced; whether there were any differences in sensitivity to IFN between the DNA and RNA virus persistent infections. The anti-viral effect of IFN was examined by its ability to inhibit Sindbis virus replication using a radioimmunoassay system. The antiproliferative effect of IFN was determined by cell counting and /sup 3/H-thymidine incorporation. The activation of the ribonuclease F, determined by the inhibition of /sup 3/H-leucine incorporation after introduction of 2-5 actin into the cells, was variable, being activated in all cell lines with the exception of the PLC/PRF/5, Hep 3B and Hep G2 cells. Major differences between the two DNA persistent infections and the two RNA persistent infections were found. No correlation was found between the presence of HBV or SV40 persistent infections and the sensitivity of the cell lines to IFN. Both the SSPE and Sendai virus persistent infections were resistant to the antiviral and antiproliferative effect of IFN.

  1. Distribution of hepatitis B virus infection in Namibia | Mhata | South ...

    African Journals Online (AJOL)

    Background. Namibia regards hepatitis B virus (HBV) infection as a public health problem and introduced hepatitis B vaccinations for infants during 2009. However, information on HBV infection in the country remains limited, and effective public health interventions may be compromised in the absence of adequate ...

  2. Prevalence of hepatitis B virus (HBV) infection among Makerere ...

    African Journals Online (AJOL)

    Background: Medical students in the course of their clinical work are at risk of acquiring hepatitis B virus (HBV) infection or transmitting it to their patients. HBV immunization for medical students in Uganda is recommended but not strictly enforced. It is important to assess the prevalence of HBV infection in medical students in ...

  3. Prevalence of hepatitis E virus infection in liver transplant recipients

    NARCIS (Netherlands)

    Haagsma, Elizabeth B; Niesters, Hubert G M; van den Berg, Arie P; Riezebos-Brilman, Annelies; Porte, Robert J; Vennema, Harry; Reimerink, Johan H J; Koopmans, Marion P G

    2009-01-01

    Hepatitis E virus (HEV) infection is known to run a self-limited course. Recently, chronic hepatitis E has been described in several immunosuppressed patients after solid organ transplantation. The prevalence of HEV infection after transplantation, however, is unknown. We studied HEV parameters [HEV

  4. Pathogenesis of herpes simplex virus infections of the cornea

    NARCIS (Netherlands)

    J. Maertzdorf (Jeroen)

    2002-01-01

    textabstractThe identification of human herpes virus (HHV) infections can be traced back to ancient Greece where Herpes simplex vims (HSV) infections in humans were first documented. Hippocrates used the word "herpes", meaning to creep or crawl, to describe spreading skin lesions. Although the

  5. Dengue virus life cycle : viral and host factors modulating infectivity

    NARCIS (Netherlands)

    Rodenhuis-Zybert, Izabela A.; Wilschut, Jan; Smit, Jolanda M.

    Dengue virus (DENV 1-4) represents a major emerging arthropod-borne pathogen. All four DENV serotypes are prevalent in the (sub) tropical regions of the world and infect 50-100 million individuals annually. Whereas the majority of DENV infections proceed asymptomatically or result in self-limited

  6. Seroprevalence and Correlates of Hepatitis C Virus Infection in ...

    African Journals Online (AJOL)

    Background: Although children comprise a small fraction of the burden of hepatitis C virus (HCV) infections, which is a major global health challenge, a significant number of them develop chronic HCV infection and are at risk of its complications. Aim: The aim of the current study was to determine the prevalence and ...

  7. Hepatitis C virus infection in patients with oral lichen planus ...

    African Journals Online (AJOL)

    Background: Lichen planus (LP) is a chronic mucocutaneous disease of uncertain etiology. Recent reports suggest that LP is an extrahepatic manifestation of Hepatitis C infection. Objective: To determine the association of Hepatitis C virus (HCV) infection with oral LP and to study the tests of liver function in patients with ...

  8. Vaccination against acute respiratory virus infections and measles in man.

    NARCIS (Netherlands)

    A.D.M.E. Osterhaus (Albert); P. de Vries (Petra)

    1992-01-01

    textabstractSeveral viruses may cause more or less severe acute respiratory infections in man, some of which are followed by systemic infection. Only for influenza and measles are licensed vaccines available at present. The protection induced by influenza vaccines, which are based on inactivated

  9. Hepatitis C virus infection among transmission-prone medical personnel

    NARCIS (Netherlands)

    Zaaijer, H. L.; Appelman, P.; Frijstein, G.

    2012-01-01

    Hepatitis C virus (HCV)-infected physicians have been reported to infect some of their patients during exposure-prone procedures (EPPs). There is no European consensus on the policy for the prevention of this transmission. To help define an appropriate preventive policy, we determined the prevalence

  10. Chronic hepatitis E virus infection in liver transplant recipients

    NARCIS (Netherlands)

    Haagsma, Elizabeth B.; van den Berg, Arie P.; Porte, Robert J.; Benne, Cornelis A.; Vennema, Harry; Reimerink, Johan H. J.; Koopmans, Marion P. G.

    Hepatitis E virus (HEV) infection is known to run a self-limiting course. Sporadic cases of acute hepatitis due to infection with HEV genotype 3, present in pig populations, are increasingly recognized. Zoonotic transmission seems infrequent. The entity of unexplained chronic hepatitis after liver

  11. Fracture risk in hepatitis C virus infected persons

    DEFF Research Database (Denmark)

    Hansen, Ann-Brit Eg; Omland, Lars Haukali; Krarup, Henrik

    2014-01-01

    BACKGROUND & AIMS: The association between Hepatitis C virus (HCV)-infection and fracture risk is not well characterized. We compared fracture risk between HCV-seropositive (HCV-exposed) patients and the general population and between patients with cleared and chronic HCV-infection. METHODS...

  12. Fulminant hepatitis B virus (HBV) infection in an infant following ...

    African Journals Online (AJOL)

    Fulminant hepatitis B virus (HBV) infection in an infant following mother-to-child transmission of an e-minus HBV mutant: Time to relook at HBV prophylaxis in South ... immune responses, and its absence was probably responsible for the infant's fulminant hepatitis, due to an uncontrolled immune attack on infected liver cells.

  13. The Prevalence of Human Immunodeficiency Virus Infection among ...

    African Journals Online (AJOL)

    AJRH Managing Editor

    Agboghoroma et al. HIV Infection Diagnosed in Women in Labour. African Journal of Reproductive Health September 2015; 19 (3):137. ORIGINAL RESEARCH ARTICLE. The Prevalence of Human Immunodeficiency Virus Infection among. Pregnant Women in Labour with Unknown Status and those with. Negative status ...

  14. Neuromuscular Manifestations of West Nile Virus Infection

    Directory of Open Access Journals (Sweden)

    A. Arturo eLeis

    2012-03-01

    Full Text Available The most common neuromuscular manifestation of West Nile virus (WNV infection is a poliomyelitis syndrome with asymmetric paralysis variably involving one (monoparesis to four limbs (quadriparesis, with or without brainstem involvement and respiratory failure. This syndrome of acute flaccid paralysis may occur without overt fever or meningoencephalitis. Although involvement of anterior horn cells in the spinal cord and motor neurons in the brainstem are the major sites of pathology responsible for neuromuscular signs, inflammation also may involve skeletal or cardiac muscle (myositis, myocarditis, motor axons (polyradiculitis, peripheral nerve (Guillain-Barré syndrome, brachial plexopathy. In addition, involvement of spinal sympathetic neurons and ganglia provides a plausible explanation for autonomic instability seen in some patients. Many patients also experience prolonged subjective generalized weakness and disabling fatigue. Despite recent evidence that WNV may persist long term in the central nervous system or periphery in animals, the evidence in humans is controversial. WNV persistence would be of great concern in immunosuppressed patients or in those with prolonged or recurrent symptoms. Support for the contention that WNV can lead to autoimmune disease arises from reports of patients presenting with various neuromuscular diseases that presumably involve autoimmune mechanisms (GBS, other demyelinating neu¬ropathies, myasthenia gravis, brachial plexopathies, stiff-person syndrome, and delayed or recurrent symptoms. Although there is no specific treatment or vaccine currently approved in humans, and the standard remains supportive care, drugs that can alter the cascade of immunobiochemical events leading to neuronal death may be potentially useful (high-dose corticosteroids, interferon preparations, and intravenous immune globulin containing WNV-specific antibodies. Human experience with these agents seems promising based on anecdotal

  15. Nation-wide surveillance of human acute respiratory virus infections between 2013 and 2015 in Korea.

    Science.gov (United States)

    Kim, Jeong-Min; Jung, Hee-Dong; Cheong, Hyang-Min; Lee, Anna; Lee, Nam-Joo; Chu, Hyuk; Lee, Joo-Yeon; Kim, Sung Soon; Choi, Jang-Hoon

    2018-07-01

    The prevalence of eight respiratory viruses detected in patients with acute respiratory infections (ARIs) in Korea was investigated through analysis of data recorded by the Korea Influenza and Respiratory Viruses Surveillance System (KINRESS) from 2013 to 2015. Nasal aspirate and throat swabs specimens were collected from 36 915 patients with ARIs, and viral nucleic acids were detected by real-time (reverse-transcription) polymerase chain reaction for eight respiratory viruses, including human respiratory syncytial viruses (HRSVs), influenza viruses (IFVs), human parainfluenza viruses (HPIVs), human coronaviruses (HCoVs), human rhinovirus (HRV), human adenovirus (HAdV), human bocavirus (HBoV), and human metapneumovirus (HMPV). The overall positive rate of patient specimens was 49.4% (18 236/36 915), 5% of which carried two or more viruses simultaneously. HRV (15.6%) was the most predominantly detected virus, followed by IFVs (14.6%), HAdV (7.5%), HPIVs (5.8%), HCoVs (4.2%), HRSVs (3.6%), HBoV (1.9%), and HMPV (1.6%). Most of the ARIs were significantly correlated with clinical symptoms of fever, cough, and runny nose. Although HRV and HAdV were frequently detected throughout the year in patients, other respiratory viruses showed apparent seasonality. HRSVs and IFVs were the major causative agents of acute respiratory diseases in infants and young children. Overall, this study demonstrates a meaningful relationship between viral infection and typical manifestations of known clinical features as well as seasonality, age distribution, and co-infection among respiratory viruses. Therefore, these data could provide useful information for public health management and to enhance patient care for primary clinicians. © 2018 Wiley Periodicals, Inc.

  16. A Fluorescent Cell-Based System for Imaging Zika Virus Infection in Real-Time

    Directory of Open Access Journals (Sweden)

    Michael J. McFadden

    2018-02-01

    Full Text Available Zika virus (ZIKV is a re-emerging flavivirus that is transmitted to humans through the bite of an infected mosquito or through sexual contact with an infected partner. ZIKV infection during pregnancy has been associated with numerous fetal abnormalities, including prenatal lethality and microcephaly. However, until recent outbreaks in the Americas, ZIKV has been relatively understudied, and therefore the biology and pathogenesis of ZIKV infection remain incompletely understood. Better methods to study ZIKV infection in live cells could enhance our understanding of the biology of ZIKV and the mechanisms by which ZIKV contributes to fetal abnormalities. To this end, we developed a fluorescent cell-based reporter system allowing for live imaging of ZIKV-infected cells. This system utilizes the protease activity of the ZIKV non-structural proteins 2B and 3 (NS2B-NS3 to specifically mark virus-infected cells. Here, we demonstrate the utility of this fluorescent reporter for identifying cells infected by ZIKV strains of two lineages. Further, we use this system to determine that apoptosis is induced in cells directly infected with ZIKV in a cell-autonomous manner. Ultimately, approaches that can directly track ZIKV-infected cells at the single cell-level have the potential to yield new insights into the host-pathogen interactions that regulate ZIKV infection and pathogenesis.

  17. A new reportable disease is born: Taiwan Centers for Disease Control's response to emerging Zika virus infection.

    Science.gov (United States)

    Huang, Angela Song-En; Shu, Pei-Yun; Yang, Chin-Hui

    2016-04-01

    Zika virus infection, usually a mild disease transmitted through the bite of Aedes mosquitos, has been reported to be possibly associated with microcephaly and neurologic complications. Taiwan's first imported case of Zika virus infection was found through fever screening at airport entry in January 2016. No virus was isolated from patient's blood taken during acute illness; however, PCR products showed that the virus was of Asian lineage closely related to virus from Cambodia. To prevent Zika virus from spreading in Taiwan, the Taiwan Centers for Disease Control has strengthened efforts in quarantine and surveillance, increased Zika virus infection diagnostic capacity, implemented healthcare system preparedness plans, and enhanced vector control program through community mobilization and education. Besides the first imported case, no additional cases of Zika virus infection have been identified. Furthermore, no significant increase in the number of microcephaly or Guillain- Barré Syndrome has been observed in Taiwan. To date, there have been no autochthonous transmissions of Zika virus infection. Copyright © 2016. Published by Elsevier B.V.

  18. The Antigenic Structure of Zika Virus and Its Relation to Other Flaviviruses: Implications for Infection and Immunoprophylaxis

    Science.gov (United States)

    Stiasny, Karin

    2017-01-01

    SUMMARY Zika virus was discovered ∼70 years ago in Uganda and maintained a low profile as a human disease agent in Africa and Asia. Only recently has it caused explosive outbreaks in previously unaffected regions, first in Oceania and then in the Americas since 2015. Of special concern is the newly identified link between congenital malformations (especially microcephaly) and Zika virus infections during pregnancy. At present, it is unclear whether Zika virus changed its pathogenicity or whether the huge number of infections allowed the recognition of a previously cryptic pathogenic property. The purpose of this review is to discuss recent data on the molecular antigenic structure of Zika virus in the context of antibody-mediated neutralization and antibody-dependent enhancement (ADE) of infection, a phenomenon that has been implicated in the development of severe disease caused by the related dengue viruses. Emphasis is given to epitopes of antibodies that potently neutralize Zika virus and also to epitopes that provide antigenic links to other important human-pathogenic flaviviruses such as dengue, yellow fever, West Nile, Japanese encephalitis, and tick-borne encephalitis viruses. The antigenic cross talk between Zika and dengue viruses appears to be of special importance, since they cocirculate in many regions of endemicity and sequential infections are likely to occur frequently. New insights into the molecular antigenic structure of Zika virus and flaviviruses in general have provided the foundation for great progress made in developing Zika virus vaccines and antibodies for passive immunization. PMID:28179396

  19. Multiple Epstein-Barr virus infections in healthy individuals

    Science.gov (United States)

    Walling, Dennis M.; Brown, Abigail L.; Etienne, Wiguins; Keitel, Wendy A.; Ling, Paul D.; Butel, J. S. (Principal Investigator)

    2003-01-01

    We employed a newly developed genotyping technique with direct representational detection of LMP-1 gene sequences to study the molecular epidemiology of Epstein-Barr virus (EBV) infection in healthy individuals. Infections with up to five different EBV genotypes were found in two of nine individuals studied. These results support the hypothesis that multiple EBV infections of healthy individuals are common. The implications for the development of an EBV vaccine are discussed.

  20. Segmental Difference of the Hepatic Fibrosis from Chronic Viral Hepatitis due to Hepatitis B versus C Virus Infection: Comparison Using Dual Contrast Material-Enhanced MRI

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Jae Ho; Yu, Jeong Sik; Chung, Jae Joon; Kim, Joo Hee; Kim, Ki Whang [Gangnam Severance Hospital, Yensei University College of Medicine, Seoul (Korea, Republic of)

    2011-08-15

    We wanted to identify the geographic differences in hepatic fibrosis and their associations with the atrophy-hypertrophy complex in patients with chronic viral hepatitis using the dual-contrast material-enhanced MRI (DC-MRI) with gadopentetate dimeglumine and ferucarbotran. Patients with chronic C (n = 22) and B-viral hepatitis (n = 35) were enrolled for determining the subjective grade of fibrosis (the extent and thickness of fibrotic reticulations) in the right lobe (RL), the caudate lobe (CL), the medial segment (MS) and the lateral segment (LS) of the liver, with using a 5-grade scale, on the gradient echo T2-weighted images of DC-MRI. The fibrosis grades of different segments were compared using the Kruskal-Wallis test followed by post-hoc analysis to establish the segment-by-segment differences. The incidences of two pre-established morphologic signs of cirrhosis were also compared with each other between the two groups of patients. There were significant intersegmental differences in fibrosis grades of the C-viral group (p = 0.005), and the CL showed lower fibrosis grades as compared with the grades of the RL and MS, whereas all lobes were similarly affected in the B-viral group (p = 0.221). The presence of a right posterior hepatic notch was significantly higher in the patients with intersegmental differences of fibrosis between the RL and the CL (19 out of 25, 76%) than those without such differences (6 out of 32, 19%) (p < 0.001). An expanded gallbladder fossa showed no significant relationship (p = 0.327) with the segmental difference of the fibrosis grades between the LS and the MS. The relative lack of fibrosis in the CL with more advanced fibrosis in the RL can be a distinguishing feature to differentiate chronic C-viral hepatitis from chronic B-viral hepatitis and this is closely related to the presence of a right posterior hepatic notch.

  1. Segmental Difference of the Hepatic Fibrosis from Chronic Viral Hepatitis due to Hepatitis B versus C Virus Infection: Comparison Using Dual Contrast Material-Enhanced MRI

    International Nuclear Information System (INIS)

    Shin, Jae Ho; Yu, Jeong Sik; Chung, Jae Joon; Kim, Joo Hee; Kim, Ki Whang

    2011-01-01

    We wanted to identify the geographic differences in hepatic fibrosis and their associations with the atrophy-hypertrophy complex in patients with chronic viral hepatitis using the dual-contrast material-enhanced MRI (DC-MRI) with gadopentetate dimeglumine and ferucarbotran. Patients with chronic C (n = 22) and B-viral hepatitis (n = 35) were enrolled for determining the subjective grade of fibrosis (the extent and thickness of fibrotic reticulations) in the right lobe (RL), the caudate lobe (CL), the medial segment (MS) and the lateral segment (LS) of the liver, with using a 5-grade scale, on the gradient echo T2-weighted images of DC-MRI. The fibrosis grades of different segments were compared using the Kruskal-Wallis test followed by post-hoc analysis to establish the segment-by-segment differences. The incidences of two pre-established morphologic signs of cirrhosis were also compared with each other between the two groups of patients. There were significant intersegmental differences in fibrosis grades of the C-viral group (p = 0.005), and the CL showed lower fibrosis grades as compared with the grades of the RL and MS, whereas all lobes were similarly affected in the B-viral group (p = 0.221). The presence of a right posterior hepatic notch was significantly higher in the patients with intersegmental differences of fibrosis between the RL and the CL (19 out of 25, 76%) than those without such differences (6 out of 32, 19%) (p < 0.001). An expanded gallbladder fossa showed no significant relationship (p = 0.327) with the segmental difference of the fibrosis grades between the LS and the MS. The relative lack of fibrosis in the CL with more advanced fibrosis in the RL can be a distinguishing feature to differentiate chronic C-viral hepatitis from chronic B-viral hepatitis and this is closely related to the presence of a right posterior hepatic notch.

  2. Zika virus infection and its emerging trends in Southeast Asia

    Institute of Scientific and Technical Information of China (English)

    Ahmad Ruzain Salehuddin; Haszianaliza Haslan; Norshalizah Mamikutty; Nurul Hannim Zaidun; Mohamad Fairuz Azmi; Mohamad Mu'izuddin Senin; Syed Baharom Syed Ahmad Fuad; Zar Chi Thent

    2017-01-01

    Zika virus is a mosquito-borne flavivirus that represents a public health emergency at the ongoing epidemic. Previously, this rare virus was limited to sporadic cases in Africa and Asia until its emergence in Brazil, South America in 2015, where it rapidly spread throughout the world. Recently, a high number of cases were reported in Singapore and other Southeast Asia countries. A combination of factors explains the current Zika virus outbreak although it is highly likely that the changes in the climate and high frequency of travelling contribute to the spread of Aedes vector carrying the Zika virus mainly to the tropical climate countries such as the Southeast Asia. The Zika virus is known to cause mild clinical symptoms similar to those of dengue and chikungunya and transmitted by different species of Aedes mosquitoes. However, neurological complications such as Guillain-Barré syndrome in adults, and congenital anomalies, including microcephaly in babies born to infected mothers, raised a serious concern. Currently, there is no specific antiviral treatment or vaccine available for Zika virus infection. Therefore, international public health response is primarily focused on preventing infection, particularly in pregnant women, and on providing up-to-date recommendations to reduce the risk of non-vector transmission of Zika virus.

  3. Why Zika virus infection has become a public health concern?

    Science.gov (United States)

    Chen, Hui-Lan; Tang, Ren-Bin

    2016-04-01

    Prior to 2015, Zika Virus (ZIKV) outbreaks had occurred in areas of Africa, Southeast Asia, and the Pacific Islands. Although a causal relationship between Zika infection during pregnancy and microcephaly is strongly suspected, such a connection has not yet been scientifically proven. In May 2015, the outbreak of ZIKV infection in Brazil led to reports of syndrome and pregnant women giving birth to babies with birth defects and poor pregnancy outcomes; the Pan American Health Organization (PAHO) issued an alert regarding the first confirmed ZIKV infection in Brazil. Currently, ZIKV outbreaks are ongoing and it will be difficult to predict how the virus will spread over time. ZIKV is transmitted to humans primarily through the bite of infected mosquitos, Aedes aegypti and Aedes albopictus. These mosquitoes are the principle vectors of dengue, and ZIKV disease generally is reported to include symptoms associated with acute febrile illnesses that clinically resembles dengue fever. The laboratory diagnosis can be performed by using reverse-transcriptase polymerase chain reaction (RT-PCR) on serum, viral nucleic acid and virus-specific immunoglobulin M. There is currently no vaccine and antiviral treatment available for ZIKV infection, and the only way to prevent congenital ZIKV infection is to prevent maternal infection. In February 2016, the Taiwan Centers for Disease Control (Taiwan CDC) activated ZIKV as a Category V Notifiable Infectious Disease similar to Ebola virus disease and MERS. Copyright © 2016. Published by Elsevier Taiwan LLC.

  4. Why Zika virus infection has become a public health concern?

    Directory of Open Access Journals (Sweden)

    Hui-Lan Chen

    2016-04-01

    Full Text Available Prior to 2015, Zika Virus (ZIKV outbreaks had occurred in areas of Africa, Southeast Asia, and the Pacific Islands. Although a causal relationship between Zika infection during pregnancy and microcephaly is strongly suspected, such a connection has not yet been scientifically proven. In May 2015, the outbreak of ZIKV infection in Brazil led to reports of syndrome and pregnant women giving birth to babies with birth defects and poor pregnancy outcomes; the Pan American Health Organization (PAHO issued an alert regarding the first confirmed ZIKV infection in Brazil. Currently, ZIKV outbreaks are ongoing and it will be difficult to predict how the virus will spread over time. ZIKV is transmitted to humans primarily through the bite of infected mosquitos, Aedes aegypti and Aedes albopictus. These mosquitoes are the principle vectors of dengue, and ZIKV disease generally is reported to include symptoms associated with acute febrile illnesses that clinically resembles dengue fever. The laboratory diagnosis can be performed by using reverse-transcriptase polymerase chain reaction (RT-PCR on serum, viral nucleic acid and virus-specific immunoglobulin M. There is currently no vaccine and antiviral treatment available for ZIKV infection, and the only way to prevent congenital ZIKV infection is to prevent maternal infection. In February 2016, the Taiwan Centers for Disease Control (Taiwan CDC activated ZIKV as a Category V Notifiable Infectious Disease similar to Ebola virus disease and MERS.

  5. Emerging Zika virus infection:What should we know?

    Institute of Scientific and Technical Information of China (English)

    Viroj Wiwanitkit

    2016-01-01

    Zika virus infection is a new emerging viral disease that becomes the present public health threat. At present, this infection can be seen in several countries. The clinical presentation of this infection is a dengue-like illness. Nevertheless, the new information shows that the disease can be sexually transmitted and transplacentally transmitted. In addition, the recent evidence from the recent epidemic in South America shows that the infection in pregnancy can cause neonatal neurological defect. In this short review, the author summarizes and presents interesting data on clinical features of this new emerging infection.

  6. Emerging Zika virus infection: What should we know?

    Directory of Open Access Journals (Sweden)

    Viroj Wiwanitkit

    2016-07-01

    Full Text Available Zika virus infection is a new emerging viral disease that becomes the present public health threat. At present, this infection can be seen in several countries. The clinical presentation of this infection is a dengue-like illness. Nevertheless, the new information shows that the disease can be sexually transmitted and transplacentally transmitted. In addition, the recent evidence from the recent epidemic in South America shows that the infection in pregnancy can cause neonatal neurological defect. In this short review, the author summarizes and presents interesting data on clinical features of this new emerging infection.

  7. Selective receptor expression restricts Nipah virus infection of endothelial cells

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    Diederich Sandra

    2008-11-01

    Full Text Available Abstract Nipah virus (NiV is a highly pathogenic paramyxovirus that causes severe diseases in animals and humans. Endothelial cell (EC infection is an established hallmark of NiV infection in vivo. Despite systemic virus spread via the vascular system, EC in brain and lung are preferentially infected whereas EC in other organs are less affected. As in vivo, we found differences in the infection of EC in cell culture. Only brain-derived primary or immortalized EC were found to be permissive to NiV infection. Using a replication-independent fusion assay, we could show that the lack of infection in non-brain EC was due to a lack of receptor expression. The NiV entry receptors ephrinB2 (EB2 or ephrinB3 were only expressed in brain endothelia. The finding that EB2 expression in previously non-permissive aortic EC rendered the cells permissive to infection then demonstrated that EB2 is not only necessary but also sufficient to allow the establishment of a productive NiV infection. This strongly suggests that limitations in receptor expression restrict virus entry in certain EC subsets in vivo, and are thus responsible for the differences in EC tropism observed in human and animal NiV infections.

  8. Local Risk Factors in Genital Human Papilloma Virus Infection in ...

    African Journals Online (AJOL)

    Keywords: Genital human papilloma virus, Pap smear, Risk factors. Access this article online .... their Pap smears taken and questionnaires on sexual attitudes, .... the high‑risk types, which mediate the response of the enhancer to steroid ...

  9. Screening Criteria for Ophthalmic Manifestations of Congenital Zika Virus Infection.

    Science.gov (United States)

    Zin, Andrea A; Tsui, Irena; Rossetto, Julia; Vasconcelos, Zilton; Adachi, Kristina; Valderramos, Stephanie; Halai, Umme-Aiman; Pone, Marcos Vinicius da Silva; Pone, Sheila Moura; Silveira Filho, Joel Carlos Barros; Aibe, Mitsue S; da Costa, Ana Carolina C; Zin, Olivia A; Belfort, Rubens; Brasil, Patricia; Nielsen-Saines, Karin; Moreira, Maria Elisabeth Lopes

    2017-09-01

    Current guidelines recommend screening eye examinations for infants with microcephaly or laboratory-confirmed Zika virus infection but not for all infants potentially exposed to Zika virus in utero. To evaluate eye findings in a cohort of infants whose mothers had polymerase chain reaction-confirmed Zika virus infection during pregnancy. In this descriptive case series performed from January 2 through October 30, 2016, infants were examined from birth to 1 year of age by a multidisciplinary medical team, including a pediatric ophthalmologist, from Fernandes Figueira Institute, a Ministry of Health referral center for high-risk pregnancies and infectious diseases in children in Rio de Janeiro, Brazil. Mother-infant pairs from Rio de Janeiro, Brazil, who presented with suspected Zika virus infection during pregnancy were referred to our institution and had serum, urine, amniotic fluid, or placenta samples tested by real-time polymerase chain reaction for Zika virus. Description of eye findings, presence of microcephaly or other central nervous system abnormalities, and timing of infection in infants with confirmed Zika virus during pregnancy. Eye abnormalities were correlated with central nervous system findings, microcephaly, and the timing of maternal infection. Of the 112 with polymerase chain reaction-confirmed Zika virus infection in maternal specimens, 24 infants (21.4%) examined had eye abnormalities (median age at first eye examination, 31 days; range, 0-305 days). Ten infants (41.7%) with eye abnormalities did not have microcephaly, and 8 (33.3%) did not have any central nervous system findings. Fourteen infants with eye abnormalities (58.3%) were born to women infected in the first trimester, 8 (33.3%) in the second trimester, and 2 (8.3%) in the third trimester. Optic nerve and retinal abnormalities were the most frequent findings. Eye abnormalities were statistically associated with microcephaly (odds ratio [OR], 19.1; 95% CI, 6.0-61.0), other central

  10. A Perfect Storm: Increased Colonization and Failure of Vaccination Leads to Severe Secondary Bacterial Infection in Influenza Virus-Infected Obese Mice

    Directory of Open Access Journals (Sweden)

    Erik A. Karlsson

    2017-09-01

    Full Text Available Obesity is a risk factor for developing severe disease following influenza virus infection; however, the comorbidity of obesity and secondary bacterial infection, a serious complication of influenza virus infections, is unknown. To fill this gap in knowledge, lean and obese C57BL/6 mice were infected with a nonlethal dose of influenza virus followed by a nonlethal dose of Streptococcus pneumoniae. Strikingly, not only did significantly enhanced death occur in obese coinfected mice compared to lean controls, but also high mortality was seen irrespective of influenza virus strain, bacterial strain, or timing of coinfection. This result was unexpected, given that most influenza virus strains, especially seasonal human A and B viruses, are nonlethal in this model. Both viral and bacterial titers were increased in the upper respiratory tract and lungs of obese animals as early as days 1 and 2 post-bacterial infection, leading to a significant decrease in lung function. This increased bacterial load correlated with extensive cellular damage and upregulation of platelet-activating factor receptor, a host receptor central to pneumococcal invasion. Importantly, while vaccination of obese mice against either influenza virus or pneumococcus failed to confer protection, antibiotic treatment was able to resolve secondary bacterial infection-associated mortality. Overall, secondary bacterial pneumonia could be a widespread, unaddressed public health problem in an increasingly obese population.

  11. Statins Suppress Ebola Virus Infectivity by Interfering with Glycoprotein Processing.

    Science.gov (United States)

    Shrivastava-Ranjan, Punya; Flint, Mike; Bergeron, Éric; McElroy, Anita K; Chatterjee, Payel; Albariño, César G; Nichol, Stuart T; Spiropoulou, Christina F

    2018-05-01

    Ebola virus (EBOV) infection is a major public health concern due to high fatality rates and limited effective treatments. Statins, widely used cholesterol-lowering drugs, have pleiotropic mechanisms of action and were suggested as potential adjunct therapy for Ebola virus disease (EVD) during the 2013-2016 outbreak in West Africa. Here, we evaluated the antiviral effects of statin (lovastatin) on EBOV infection in vitro Statin treatment decreased infectious EBOV production in primary human monocyte-derived macrophages and in the hepatic cell line Huh7. Statin treatment did not interfere with viral entry, but the viral particles released from treated cells showed reduced infectivity due to inhibition of viral glycoprotein processing, as evidenced by decreased ratios of the mature glycoprotein form to precursor form. Statin-induced inhibition of infectious virus production and glycoprotein processing was reversed by exogenous mevalonate, the rate-limiting product of the cholesterol biosynthesis pathway, but not by low-density lipoprotein. Finally, statin-treated cells produced EBOV particles devoid of the surface glycoproteins required for virus infectivity. Our findings demonstrate that statin treatment inhibits EBOV infection and suggest that the efficacy of statin treatment should be evaluated in appropriate animal models of EVD. IMPORTANCE Treatments targeting Ebola virus disease (EVD) are experimental, expensive, and scarce. Statins are inexpensive generic drugs that have been used for many years for the treatment of hypercholesterolemia and have a favorable safety profile. Here, we show the antiviral effects of statins on infectious Ebola virus (EBOV) production. Our study reveals a novel molecular mechanism in which statin regulates EBOV particle infectivity by preventing glycoprotein processing and incorporation into virus particles. Additionally, statins have anti-inflammatory and immunomodulatory effects. Since inflammation and dysregulation of the immune

  12. Avian Influenza A Viruses: Evolution and Zoonotic Infection.

    Science.gov (United States)

    Kim, Se Mi; Kim, Young-Il; Pascua, Philippe Noriel Q; Choi, Young Ki

    2016-08-01

    Although efficient human-to-human transmission of avian influenza virus has yet to be seen, in the past two decades avian-to-human transmission of influenza A viruses has been reported. Influenza A/H5N1, in particular, has repeatedly caused human infections associated with high mortality, and since 1998 the virus has evolved into many clades of variants with significant antigenic diversity. In 2013, three (A/H7N9, A/H6N1, and A/H10N8) novel avian influenza viruses (AIVs) breached the animal-human host species barrier in Asia. In humans, roughly 35% of A/H7N9-infected patients succumbed to the zoonotic infection, and two of three A/H10N8 human infections were also lethal; however, neither of these viruses cause influenza-like symptoms in poultry. While most of these cases were associated with direct contact with infected poultry, some involved sustained human-to-human transmission. Thus, these events elicited concern regarding potential AIV pandemics. This article reviews the human incursions associated with AIV variants and the potential role of pigs as an intermediate host that may hasten AIV evolution. In addition, we discuss the known influenza A virus virulence and transmission factors and their evaluation in animal models. With the growing number of human AIV infections, constant vigilance for the emergence of novel viruses is of utmost importance. In addition, careful characterization and pathobiological assessment of these novel variants will help to identify strains of particular concern for future pandemics. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  13. Human natural killer cells prevent infectious mononucleosis features by targeting lytic Epstein-Barr virus infection.

    Science.gov (United States)

    Chijioke, Obinna; Müller, Anne; Feederle, Regina; Barros, Mario Henrique M; Krieg, Carsten; Emmel, Vanessa; Marcenaro, Emanuela; Leung, Carol S; Antsiferova, Olga; Landtwing, Vanessa; Bossart, Walter; Moretta, Alessandro; Hassan, Rocio; Boyman, Onur; Niedobitek, Gerald; Delecluse, Henri-Jacques; Capaul, Riccarda; Münz, Christian

    2013-12-26

    Primary infection with the human oncogenic Epstein-Barr virus (EBV) can result in infectious mononucleosis (IM), a self-limiting disease caused by massive lymphocyte expansion that predisposes for the development of distinct EBV-associated lymphomas. Why some individuals experience this symptomatic primary EBV infection, whereas the majority acquires the virus asymptomatically, remains unclear. Using a mouse model with reconstituted human immune system components, we show that depletion of human natural killer (NK) cells enhances IM symptoms and promotes EBV-associated tumorigenesis mainly because of a loss of immune control over lytic EBV infection. These data suggest that failure of innate immune control by human NK cells augments symptomatic lytic EBV infection, which drives lymphocyte expansion and predisposes for EBV-associated malignancies. Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.

  14. Human Natural Killer Cells Prevent Infectious Mononucleosis Features by Targeting Lytic Epstein-Barr Virus Infection

    Directory of Open Access Journals (Sweden)

    Obinna Chijioke

    2013-12-01

    Full Text Available Primary infection with the human oncogenic Epstein-Barr virus (EBV can result in infectious mononucleosis (IM, a self-limiting disease caused by massive lymphocyte expansion that predisposes for the development of distinct EBV-associated lymphomas. Why some individuals experience this symptomatic primary EBV infection, whereas the majority acquires the virus asymptomatically, remains unclear. Using a mouse model with reconstituted human immune system components, we show that depletion of human natural killer (NK cells enhances IM symptoms and promotes EBV-associated tumorigenesis mainly because of a loss of immune control over lytic EBV infection. These data suggest that failure of innate immune control by human NK cells augments symptomatic lytic EBV infection, which drives lymphocyte expansion and predisposes for EBV-associated malignancies.

  15. Vaccine-induced anti-HA2 antibodies promote virus fusion and enhance influenza virus respiratory disease.

    Science.gov (United States)

    Khurana, Surender; Loving, Crystal L; Manischewitz, Jody; King, Lisa R; Gauger, Phillip C; Henningson, Jamie; Vincent, Amy L; Golding, Hana

    2013-08-28

    Vaccine-induced disease enhancement has been described in connection with several viral vaccines in animal models and in humans. We investigated a swine model to evaluate mismatched influenza vaccine-associated enhanced respiratory disease (VAERD) after pH1N1 infection. Vaccinating pigs with whole inactivated H1N2 (human-like) virus vaccine (WIV-H1N2) resulted in enhanced pneumonia and disease after pH1N1 infection. WIV-H1N2 immune sera contained high titers of cross-reactive anti-pH1N1 hemagglutinin (HA) antibodies that bound exclusively to the HA2 domain but not to the HA1 globular head. No hemagglutination inhibition titers against pH1N1 (challenge virus) were measured. Epitope mapping using phage display library identified the immunodominant epitope recognized by WIV-H1N2 immune sera as amino acids 32 to 77 of pH1N1-HA2 domain, close to the fusion peptide. These cross-reactive anti-HA2 antibodies enhanced pH1N1 infection of Madin-Darby canine kidney cells by promoting virus membrane fusion activity. The enhanced fusion activity correlated with lung pathology in pigs. This study suggests a role for fusion-enhancing anti-HA2 antibodies in VAERD, in the absence of receptor-blocking virus-neutralizing antibodies. These findings should be considered during the evaluation of universal influenza vaccines designed to elicit HA2 stem-targeting antibodies.

  16. Hepatitis B and C virus co-infections in human immunodeficiency virus positive North Indian patients

    Science.gov (United States)

    Gupta, Swati; Singh, Sarman

    2006-01-01

    AIM: To determine the prevalence of hepatitis B and C virus infections in human immunodeficiency virus (HIV) -positive patients at a tertiary care hospital in New Delhi, India. METHODS: Serum samples from 451 HIV positive patients were analyzed for HBsAg and HCV antibodies during three years (Jan 2003-Dec 2005). The control group comprised of apparently healthy bone-marrow and renal donors. RESULTS: The study population comprised essentially of heterosexually transmitted HIV infection. The prevalence rate of HBsAg in this population was 5.3% as compared to 1.4% in apparently healthy donors (P < 0.001). Though prevalence of HCV co-infection (2.43%) was lower than HBV in this group of HIV positive patients, the prevalence was significantly higher (P < 0.05) than controls (0.7%). Triple infection of HIV, HBV and HCV was not detected in any patient. CONCLUSION: Our study shows a significantly high prevalence of hepatitis virus infections in HIV infected patients. Hepatitis viruses in HIV may lead to faster progression to liver cirrhosis and a higher risk of antiretroviral therapy induced hepatotoxicity. Therefore, it would be advisable to detect hepatitis virus co-infections in these patients at the earliest. PMID:17106941

  17. Dynamics of Persistent and Acute Deformed Wing Virus Infections in Honey Bees, Apis mellifera

    Directory of Open Access Journals (Sweden)

    Jay D. Evans

    2011-12-01

    Full Text Available The dynamics of viruses are critical to our understanding of disease pathogenesis. Using honey bee Deformed wing virus (DWV as a model, we conducted field and laboratory studies to investigate the roles of abiotic and biotic stress factors as well as host health conditions in dynamics of virus replication in honey bees. The results showed that temperature decline could lead to not only significant decrease in the rate for pupae to emerge as adult bees, but also an increased severity of the virus infection in emerged bees, partly explaining the high levels of winter losses of managed honey bees, Apis mellifera, around the world. By experimentally exposing adult bees with variable levels of parasitic mite Varroa destructor, we showed that the severity of DWV infection was positively correlated with the density and time period of Varroa mite infestation, confirming the role of Varroa mites in virus transmission and activation in honey bees. Further, we showed that host conditions have a significant impact on the outcome of DWV infection as bees that originate from strong colonies resist DWV infection and replication significantly better than bee originating from weak colonies. The information obtained from this study has important implications for enhancing our understanding of host‑pathogen interactions and can be used to develop effective disease control strategies for honey bees.

  18. Social stigmatization and hepatitis C virus infection.

    Science.gov (United States)

    Zacks, Steven; Beavers, Kimberly; Theodore, Dickens; Dougherty, Karen; Batey, Betty; Shumaker, Jeremy; Galanko, Joseph; Shrestha, Roshan; Fried, Michael W

    2006-03-01

    Our aim was to assess stigmatization by evaluating the impact of hepatitis C virus (HCV) on social interactions, feelings of rejection, internalized shame, and financial insecurity, and behavior. HCV patients suffer from slowly progressive disease. Although much research has improved the long-term prognosis of chronic HCV, quality of life may be affected by perceived social stigmatization. In a cross-sectional study, HCV patients without cirrhosis or significant comorbidities were recruited from the University of North Carolina viral hepatitis clinic. Subjects completed a questionnaire administered by a trained interviewer that assessed changes in sexual behavior, personal hygiene habits, social function, and interactions. Additionally, subjects completed validated, standardized questionnaires, the Health Status Questionnaire, and the SCL-90-R. Frequencies were calculated for the prevalence of stigmatization and altered social interaction. Correlations between education and behavior changes were assessed. A series of multivariate analyses controlling for age, sex, and education were performed to assess the association between HCV acquisition risk and stigmatization. One hundred seventy-five of 217 potential subjects (81%) participated in the survey. The average age was 45.2+/-7.7 years. Fifty-five percent were men and 53% were single. Twenty-nine percent had some college education. Risk factors for HCV acquisition included transfusion (21%) and injection drug use (29%), whereas 32% had an unknown mode of infection. Among common activities, 47% were less likely to share drinking glasses, 14% were less likely to prepare food, and one-third of subjects were less likely to share a towel. Thirty-five percent of respondents reported changes in their sexual practices. Decreased frequency of kissing and sexual intercourse was reported in 20% and 27% of individuals, respectively. Almost half of the single subjects reported increased use of condoms compared with only 20

  19. Cyclophilin B enhances HIV-1 infection

    Energy Technology Data Exchange (ETDEWEB)

    DeBoer, Jason; Madson, Christian J. [Department of Medical Microbiology and Immunology, Creighton University, Omaha, NE (United States); Belshan, Michael, E-mail: michaelbelshan@creighton.edu [Department of Medical Microbiology and Immunology, Creighton University, Omaha, NE (United States); The Nebraska Center for Virology, University of Nebraska, Lincoln, NE (United States)

    2016-02-15

    Cyclophilin B (CypB) is a member of the immunophilin family and intracellular chaperone. It predominantly localizes to the ER, but also contains a nuclear localization signal and is secreted from cells. CypB has been shown to interact with the Gag protein of human immunodeficiency type 1 (HIV-1). Several proteomic and genetic studies identified it as a potential factor involved in HIV replication. Herein, we show that over-expression of CypB enhances HIV infection by increasing nuclear import of viral DNA. This enhancement was unaffected by cyclosporine treatment and requires the N-terminus of the protein. The N-terminus contains an ER leader sequence, putative nuclear localization signal, and is required for secretion. Deletion of the N-terminus resulted in mislocalization from the ER and suppression of HIV infection. Passive transfer experiments showed that secreted CypB did not impact HIV infection. Combined, these experiments show that intracellular CypB modulates a pathway of HIV nuclear import. - Highlights: • CypB has been identified in several proteomic studies of HIV-1 infection. • CypB expression is upregulated in activated and infected T-cells. • Over-expression of CypB enhances HIV nuclear import and infection. • The N-terminus of CypB is necessary for these effects.

  20. Cyclophilin B enhances HIV-1 infection

    International Nuclear Information System (INIS)

    DeBoer, Jason; Madson, Christian J.; Belshan, Michael

    2016-01-01

    Cyclophilin B (CypB) is a member of the immunophilin family and intracellular chaperone. It predominantly localizes to the ER, but also contains a nuclear localization signal and is secreted from cells. CypB has been shown to interact with the Gag protein of human immunodeficiency type 1 (HIV-1). Several proteomic and genetic studies identified it as a potential factor involved in HIV replication. Herein, we show that over-expression of CypB enhances HIV infection by increasing nuclear import of viral DNA. This enhancement was unaffected by cyclosporine treatment and requires the N-terminus of the protein. The N-terminus contains an ER leader sequence, putative nuclear localization signal, and is required for secretion. Deletion of the N-terminus resulted in mislocalization from the ER and suppression of HIV infection. Passive transfer experiments showed that secreted CypB did not impact HIV infection. Combined, these experiments show that intracellular CypB modulates a pathway of HIV nuclear import. - Highlights: • CypB has been identified in several proteomic studies of HIV-1 infection. • CypB expression is upregulated in activated and infected T-cells. • Over-expression of CypB enhances HIV nuclear import and infection. • The N-terminus of CypB is necessary for these effects.

  1. Transmission of West Nile virus by Culex quinquefasciatus say infected with Culex Flavivirus Izabal.

    Directory of Open Access Journals (Sweden)

    Rebekah J Kent

    Full Text Available BACKGROUND: The natural history and potential impact of mosquito-specific flaviviruses on the transmission efficiency of West Nile virus (WNV is unknown. The objective of this study was to determine whether or not prior infection with Culex flavivirus (CxFV Izabal altered the vector competence of Cx. quinquefasciatus Say for transmission of a co-circulating strain of West Nile virus (WNV from Guatemala. METHODS AND FINDINGS: CxFV-negative Culex quinquefasciatus and those infected with CxFV Izabal by intrathoracic inoculation were administered WNV-infectious blood meals. Infection, dissemination, and transmission of WNV were measured by plaque titration on Vero cells of individual mosquito bodies, legs, or saliva, respectively, two weeks following WNV exposure. Additional groups of Cx. quinquefasciatus were intrathoracically inoculated with WNV alone or WNV+CxFV Izabal simultaneously, and saliva collected nine days post inoculation. Growth of WNV in Aedes albopictus C6/36 cells or Cx. quinquefasciatus was not inhibited by prior infection with CxFV Izabal. There was no significant difference in the vector competence of Cx. quinquefasciatus for WNV between mosquitoes uninfected or infected with CxFV Izabal across multiple WNV blood meal titers and two colonies of Cx. quinquefasciatus (p>0.05. However, significantly more Cx. quinquefasciatus from Honduras that were co-inoculated simultaneously with both viruses transmitted WNV than those inoculated with WNV alone (p = 0.0014. Co-inoculated mosquitoes that transmitted WNV also contained CxFV in their saliva, whereas mosquitoes inoculated with CxFV alone did not contain virus in their saliva. CONCLUSIONS: In the sequential infection experiments, prior infection with CxFV Izabal had no significant impact on WNV replication, infection, dissemination, or transmission by Cx. quinquefasciatus, however WNV transmission was enhanced in the Honduras colony when mosquitoes were inoculated simultaneously with

  2. A systems immunology approach to plasmacytoid dendritic cell function in cytopathic virus infections.

    Directory of Open Access Journals (Sweden)

    Gennady Bocharov

    Full Text Available Plasmacytoid dendritic cell (pDC-mediated protection against cytopathic virus infection involves various molecular, cellular, tissue-scale, and organism-scale events. In order to better understand such multiscale interactions, we have implemented a systems immunology approach focusing on the analysis of the structure, dynamics and operating principles of virus-host interactions which constrain the initial spread of the pathogen. Using high-resolution experimental data sets coming from the well-described mouse hepatitis virus (MHV model, we first calibrated basic modules including MHV infection of its primary target cells, i.e. pDCs and macrophages (Mphis. These basic building blocks were used to generate and validate an integrative mathematical model for in vivo infection dynamics. Parameter estimation for the system indicated that on a per capita basis, one infected pDC secretes sufficient type I IFN to protect 10(3 to 10(4 Mphis from cytopathic viral infection. This extremely high protective capacity of pDCs secures the spleen's capability to function as a 'sink' for the virus produced in peripheral organs such as the liver. Furthermore, our results suggest that the pDC population in spleen ensures a robust protection against virus variants which substantially down-modulate IFN secretion. However, the ability of pDCs to protect against severe disease caused by virus variants exhibiting an enhanced liver tropism and higher replication rates appears to be rather limited. Taken together, this systems immunology analysis suggests that antiviral therapy against cytopathic viruses should primarily limit viral replication within peripheral target organs.

  3. Towards antiviral therapies for treating dengue virus infections.

    Science.gov (United States)

    Kaptein, Suzanne Jf; Neyts, Johan

    2016-10-01

    Dengue virus is an emerging human pathogen that poses a huge public health burden by infecting annually about 390 million individuals of which a quarter report with clinical manifestations. Although progress has been made in understanding dengue pathogenesis, a licensed vaccine or antiviral therapy against this virus is still lacking. Treatment of patients is confined to symptomatic alleviation and supportive care. The development of dengue therapeutics thus remains of utmost importance. This review focuses on the few molecules that were evaluated in dengue virus-infected patients: balapiravir, chloroquine, lovastatin, prednisolone and celgosivir. The lessons learned from these clinical trials can be very helpful for the design of future trials for the next generation of dengue virus inhibitors. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Does a feline leukemia virus infection pave the way for Bartonella henselae infection in cats?

    Science.gov (United States)

    Buchmann, Alexandra U; Kershaw, Olivia; Kempf, Volkhard A J; Gruber, Achim D

    2010-09-01

    Domestic cats serve as the reservoir hosts of Bartonella henselae and may develop mild clinical symptoms or none after experimental infection. In humans, B. henselae infection can result in self-limiting cat scratch disease. However, immunocompromised patients may suffer from more-severe courses of infection or may even develop the potentially lethal disease bacillary angiomatosis. It was reasoned that cats with immunocompromising viral infections may react similarly to B. henselae infection. The aim of our study was to investigate the influence of the most important viruses known to cause immunosuppression in cats-Feline leukemia virus (FeLV), Feline immunodeficiency virus (FIV), and Feline panleukopenia virus (FPV)-on natural B. henselae infection in cats. Accordingly, 142 cats from animal shelters were necropsied and tested for B. henselae and concurrent infections with FeLV, FIV, or FPV by PCR and immunohistochemistry. A significant association was found between B. henselae and FeLV infections (P = 0.00028), but not between B. henselae and FIV (P = 1.0) or FPV (P = 0.756) infection, age (P = 0.392), or gender (P = 0.126). The results suggest that susceptibility to B. henselae infection is higher in cats with concurrent FeLV infections, regardless of whether the infection is latent or progressive. Histopathology and immunohistochemistry for B. henselae failed to identify lesions that could be attributed specifically to B. henselae infection. We conclude that the course of natural B. henselae infection in cats does not seem to be influenced by immunosuppressive viral infections in general but that latent FeLV infection may predispose cats to B. henselae infection or persistence.

  5. Changing clinical scenario in Chandipura virus infection

    Directory of Open Access Journals (Sweden)

    A B Sudeep

    2016-01-01

    Phlebotomine sandflies are implicated as vectors due to their predominance in endemic areas, repeated virus isolations and their ability to transmit the virus by transovarial and venereal routes. Significant contributions have been made in the development of diagnostics and prophylactics, vaccines and antivirals. Two candidate vaccines, viz. a recombinant vaccine and a killed vaccine and siRNAs targeting P and M proteins have been developed and are awaiting clinical trials. Rhabdomyosarcoma and Phlebotomus papatasi cell lines as well as embryonated chicken eggs have been found useful in virus isolation and propagation. Despite these advancements, CHPV has been a major concern in Central India and warrants immediate attention from virologists, neurologists, paediatricians and the government for containing the virus.

  6. Reduced incorporation of the influenza B virus BM2 protein in virus particles decreases infectivity

    International Nuclear Information System (INIS)

    Jackson, David; Zuercher, Thomas; Barclay, Wendy

    2004-01-01

    BM2 is the fourth integral membrane protein encoded by the influenza B virus genome. It is synthesized late in infection and transported to the plasma membrane from where it is subsequently incorporated into progeny virus particles. It has recently been reported that BM2 has ion channel activity and may be the functional homologue of the influenza A virus M2 protein acting as an ion channel involved in viral entry. Using a reverse genetic approach it was not possible to recover virus which lacked BM2. A recombinant influenza B virus was generated in which the BM2 AUG initiation codon was mutated to GUG. This decreased the efficiency of translation of BM2 protein such that progeny virions contained only 1/8 the amount of BM2 seen in wild-type virus. The reduction in BM2 incorporation resulted in a reduction in infectivity although there was no concomitant decrease in the numbers of virions released from the infected cells. These data imply that the incorporation of sufficient BM2 protein into influenza B virions is required for infectivity of the virus particles

  7. Pseudorabies virus infection alters neuronal activity and connectivity in vitro.

    Directory of Open Access Journals (Sweden)

    Kelly M McCarthy

    2009-10-01

    Full Text Available Alpha-herpesviruses, including human herpes simplex virus 1 & 2, varicella zoster virus and the swine pseudorabies virus (PRV, infect the peripheral nervous system of their hosts. Symptoms of infection often include itching, numbness, or pain indicative of altered neurological function. To determine if there is an in vitro electrophysiological correlate to these characteristic in vivo symptoms, we infected cultured rat sympathetic neurons with well-characterized strains of PRV known to produce virulent or attenuated symptoms in animals. Whole-cell patch clamp recordings were made at various times after infection. By 8 hours of infection with virulent PRV, action potential (AP firing rates increased substantially and were accompanied by hyperpolarized resting membrane potentials and spikelet-like events. Coincident with the increase in AP firing rate, adjacent neurons exhibited coupled firing events, first with AP-spikelets and later with near identical resting membrane potentials and AP firing. Small fusion pores between adjacent cell bodies formed early after infection as demonstrated by transfer of the low molecular weight dye, Lucifer Yellow. Later, larger pores formed as demonstrated by transfer of high molecular weight Texas red-dextran conjugates between infected cells. Further evidence for viral-induced fusion pores was obtained by infecting neurons with a viral mutant defective for glycoprotein B, a component of the viral membrane fusion complex. These infected neurons were essentially identical to mock infected neurons: no increased AP firing, no spikelet-like events, and no electrical or dye transfer. Infection with PRV Bartha, an attenuated circuit-tracing strain delayed, but did not eliminate the increased neuronal activity and coupling events. We suggest that formation of fusion pores between infected neurons results in electrical coupling and elevated firing rates, and that these processes may contribute to the altered neural

  8. Neonatal herpes simplex virus infection: epidemiology and treatment.

    Science.gov (United States)

    James, Scott H; Kimberlin, David W

    2015-03-01

    Herpes simplex virus types 1 (HSV-1) and 2 (HSV-2) are highly prevalent viruses capable of establishing lifelong infection. Genital herpes in women of childbearing age represents a major risk for mother-to-child transmission (MTCT) of HSV infection, with primary and first-episode genital HSV infections posing the highest risk. The advent of antiviral therapy with parenteral acyclovir has led to significant improvement in neonatal HSV disease mortality. Further studies are needed to improve the clinician's ability to identify infants at increased risk for HSV infection and prevent MTCT, and to develop novel antiviral agents with increased efficacy in infants with HSV infection. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. Avian influenza A virus and Newcastle disease virus mono- and co-infections in birds

    Directory of Open Access Journals (Sweden)

    Iv. Zarkov

    2017-06-01

    Full Text Available The main features of avian influenza viruses (AIV and Newcastle disease virus (APMV-1, the possibilities for isolation and identification in laboratory conditions, methods of diagnostics, main hosts, clinical signs and virus shedding are reviewed in chronological order. The other part of the review explains the mechanisms and interactions in cases of co-infection of AIV and APMV-1, either between them or with other pathogens in various indicator systems – cell cultures, chick embryos or birds. The emphasis is placed on quantitative data on the virus present mainly in the first ten days following experimental infection of birds, the periods of virus carrier ship and shedding, clinical signs, pathological changes, diagnostic challenges

  10. Virus isolation for diagnosing dengue virus infections in returning travelers

    NARCIS (Netherlands)

    Teichmann, D.; Göbels, K.; Niedrig, M.; Sim-Brandenburg, J.-W.; Làge-Stehr, J.; Grobusch, M. P.

    2003-01-01

    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

  11. Virus Infections on Prion Diseased Mice Exacerbate Inflammatory Microglial Response

    Science.gov (United States)

    Lins, Nara; Mourão, Luiz; Trévia, Nonata; Passos, Aline; Farias, José Augusto; Assunção, Jarila; Bento-Torres, João; Consentino Kronka Sosthenes, Marcia; Diniz, José Antonio Picanço; Vasconcelos, Pedro Fernando da Costa

    2016-01-01

    We investigated possible interaction between an arbovirus infection and the ME7 induced mice prion disease. C57BL/6, females, 6-week-old, were submitted to a bilateral intrahippocampal injection of ME7 prion strain (ME7) or normal brain homogenate (NBH). After injections, animals were organized into two groups: NBH (n = 26) and ME7 (n = 29). At 15th week after injections (wpi), animals were challenged intranasally with a suspension of Piry arbovirus 0.001% or with NBH. Behavioral changes in ME7 animals appeared in burrowing activity at 14 wpi. Hyperactivity on open field test, errors on rod bridge, and time reduction in inverted screen were detected at 15th, 19th, and 20th wpi respectively. Burrowing was more sensitive to earlier hippocampus dysfunction. However, Piry-infection did not significantly affect the already ongoing burrowing decline in the ME7-treated mice. After behavioral tests, brains were processed for IBA1, protease-resistant form of PrP, and Piry virus antigens. Although virus infection in isolation did not change the number of microglia in CA1, virus infection in prion diseased mice (at 17th wpi) induced changes in number and morphology of microglia in a laminar-dependent way. We suggest that virus infection exacerbates microglial inflammatory response to a greater degree in prion-infected mice, and this is not necessarily correlated with hippocampal-dependent behavioral deficits. PMID:28003864

  12. Serodiagnosis of Helicobacter pylori infection in patients with human immunodeficiency virus infection

    DEFF Research Database (Denmark)

    Nielsen, H; Andersen, L P

    1995-01-01

    In contrast to the established role of Helicobacter pylori gastritis in gastritis and duodenal ulcer in general, conflicting results have been reported in patients with human immunodeficiency virus (HIV) infection and the acquired immunodeficiency syndrome. The seroprevalence during early HIV...

  13. Vaccinia Virus Infections in a Martial Arts Gym

    Centers for Disease Control (CDC) Podcasts

    2011-04-04

    This podcast discusses an outbreak of vaccinia virus in Maryland in 2008. Christine Hughes, a health scientist with the Poxvirus and Rabies Branch at CDC, and co-author of a paper in the April 2011 issue of CDC's journal, discusses vaccinia virus infections in a martial arts gym.  Created: 4/4/2011 by National Center for Emerging Zoonotic and Infectious Diseases (NCEZID).   Date Released: 4/5/2011.

  14. Differentially expressed genes in healthy and plum pox virus-infected Nicotiana benthamiana plants.

    Science.gov (United States)

    Vozárová, Z; Žilová, M; Šubr, Z

    2015-12-01

    Viruses use both material and energy sources of their hosts and redirect the production of disposable compounds in order to make viral replication more efficient. Metabolism of infected organisms is modified by these enhanced requirements as well by their own defense response. Resulting complex story consists of many regulation events on various gene expression levels. Elucidating these processes may contribute to the knowledge on virus-host interactions and to evolving new antiviral strategies. In our work we applied a subtractive cloning technique to compare the transcriptomes of healthy and plum pox virus (PPV)-infected Nicotiana benthamiana plants. Several genes were found to be induced or repressed by the PPV infection. The induced genes were mainly related to general stress response or photosynthesis, several repressed genes could be connected with growth defects evoked by the infection. Interestingly, some genes usually up-regulated by fungal or bacterial infection were found repressed in PPV-infected plants. Potential involvement of particular differently expressed genes in the process of PPV infection is discussed.

  15. An in-depth analysis of original antigenic sin in dengue virus infection.

    Science.gov (United States)

    Midgley, Claire M; Bajwa-Joseph, Martha; Vasanawathana, Sirijitt; Limpitikul, Wannee; Wills, Bridget; Flanagan, Aleksandra; Waiyaiya, Emily; Tran, Hai Bac; Cowper, Alison E; Chotiyarnwong, Pojchong; Chotiyarnwon, Pojchong; Grimes, Jonathan M; Yoksan, Sutee; Malasit, Prida; Simmons, Cameron P; Mongkolsapaya, Juthathip; Screaton, Gavin R

    2011-01-01

    The evolution of dengue viruses has resulted in four antigenically similar yet distinct serotypes. Infection with one serotype likely elicits lifelong immunity to that serotype, but generally not against the other three. Secondary or sequential infections are common, as multiple viral serotypes frequently cocirculate. Dengue infection, although frequently mild, can lead to dengue hemorrhagic fever (DHF) which can be life threatening. DHF is more common in secondary dengue infections, implying a role for the adaptive immune response in the disease. There is currently much effort toward the design and implementation of a dengue vaccine but these efforts are made more difficult by the challenge of inducing durable neutralizing immunity to all four viruses. Domain 3 of the dengue virus envelope protein (ED3) has been suggested as one such candidate because it contains neutralizing epitopes and it was originally thought that relatively few cross-reactive antibodies are directed to this domain. In this study, we performed a detailed analysis of the anti-ED3 response in a cohort of patients suffering either primary or secondary dengue infections. The results show dramatic evidence of original antigenic sin in secondary infections both in terms of binding and enhancement activity. This has important implications for dengue vaccine design because heterologous boosting is likely to maintain the immunological footprint of the first vaccination. On the basis of these findings, we propose a simple in vitro enzyme-linked immunosorbent assay (ELISA) to diagnose the original dengue infection in secondary dengue cases.

  16. THE POSSIBLE COLLISIONS IN VIRUS INFECTION IMMUNODIAGNOSTICS AND VACCINATION

    Directory of Open Access Journals (Sweden)

    E. P. Kharchenko

    2016-01-01

    Full Text Available Antibodies (Ab, especially natural, display multiple specificity not only due to intrinsic conformational dynamics. With computational analysis the distribution of identical and homologous peptides has been studied in surface proteins from RNA and DNA viruses of widely distributed infections. It was established that each virus protein shared the fragments homologous to other virus proteins that allowed to propose the existence of the peptide continuum of the protein relationship (PCPR. Possible manifestations of PCPR are multiple reactivity and autoreactivity in Ab and therefore it is not possible to consider the immune methods of virus identification as high reliable because of crossing interactions. The PCPR excludes the existence of 100% specificity in immune tests for virus identification. Immunodiagnostic collisions may occur either in identification of virus itself or identification of Ab to viruses. Also PCPR may be responsible for heterologous immunity and consequently the infection associated with severe pathology. The comparative analysis of peptide relationship of H1N1 influenza virus nucleoprotein and human proteins found out, beyond early described its common motif with human hypocretin receptor 2, peptides homologous to those in melanotonin and glutamate receptors and three ion channels. It allows to propose that the sleep disorder narcolepsy associated with Pandemrix vaccination (an adjuvanted, influenza pandemic vaccine and also with infection by influenza virus during the 2009 A(H1N1 influenza pandemic may be determined not only by Ab to the peptide motif common to influenza nucleoprotein and hypocretin receptor but also Ab to melanotonin and glutamate receptors and ion channels. Decreasing and even avoiding risks of complications from vaccination may be feasible by means of a computer analysis of vaccine proteins for the occurrence of epitopes homologous to the human protein those and particularly by an analysis of Ab profiles

  17. Pepino mosaic virus and Tomato chlorosis virus causing mixed infection in protected tomato crops in Sicily

    Directory of Open Access Journals (Sweden)

    SALVATORE DAVINO

    2008-07-01

    Full Text Available An unusual virus-like yellow leaf disorder associated with fruit marbling was observed during the winter of 2005 in some greenhouse tomato crops in the province of Ragusa Sicily (Southern Italy. Leaf samples from 250 symptomatic tomato plants were serologically tested by DAS-ELISA technique for 5 viruses: Tomato spotted wilt virus (TSWV, Impatiens necrotic spot virus (INSV, Tobacco mosaic virus (TMV, Cucumber mosaic virus (CMV and Pepino mosaic virus (PepMV. PepMV was detected in 215 of the samples. The virus was mechanically transmitted to cucumber, wild metel, wild tobacco and ‘Rio Grande’ tomato. The experimental host range of PepMV-Ragusa differed from that of the PepMV found in Sardinia in 2001, which infected ‘Camone’ tomato. By applying RT-PCR to 25 PepMV-infected tomato plants, the expected 844 bp DNA fragment for PepMV and the expected 439 bp DNA fragment for Tomato chlororis virus (ToCV were obtained from all the samples tested. Sequences of the obtained amplicons were used to study the phylogenetic relationships of the viruses with isolates from other countries. Nucleotide sequence alignments showed that the sequence CP-PepMV-Ragusa (Genbank acc. No. DQ 517884 were 99% homologous with both US2 and Spain-Murcia isolates, while those of ToCV-Ragusa (Genbank acc. No. DQ517885 isolate HSP70, were 99% homologous with the Florida isolate, and 98% with the Lebanon isolate. The results proved that the unusual disorder found in greenhouse tomatoes in Sicily can be associated with infections by PepMV and ToCV, reported for the first time in a mixed infection.

  18. Congenital Abnormalities: Consequence of Maternal Zika Virus Infection: A Narrative Review.

    Science.gov (United States)

    Hassan, Fatima I; Niaz, Kamal; Maqbool, Faheem; Khan, Fazlullah; Abdollahi, Mohammad

    2017-01-01

    Zika virus (ZIKV) is a deadly flavivirus that has spread from Africa to Asia and European countries. The virus is associated with other viruses in the same genus or family, transmitted by the same mosquito species with known history of fatality. A sudden increase in the rate of infection from ZIKV has made it a global health concern, which necessitates close symptom monitoring, enhancing treatment options, and vaccine production. This paper reviewed current reports on birth defects associated with ZIKV, mode of transmission, body fluids containing the virus, diagnosis, possible preventive measures or treatments, and vaccine development. Google scholar was used as the major search engine for research and review articles, up to July, 2016. Search terms such as "ZIKV", "ZIKV infection", "ZIKV serotypes", "treatment of ZIKV infection", "co-infection with zika virus", "flavivirus", "microcephaly and zika", "birth defects and Zika", as well as "ZIKV vaccine" were used. ZIKV has been detected in several body fluids such as saliva, semen, blood, and amniotic fluid. This reveals the possibility of sexual and mother to child transmission. The ability of the virus to cross the placental barrier and the blood brain barrier (BBB) has been associated with birth defects such as microcephaly, ocular defects, and Guillian Barre syndrome (GBS). Preventive measures can reduce the spread and risk of the infection. Available treatments only target symptoms while vaccines are still under development. Birth defects are associated with ZIKV infection in pregnant women; hence the need for development of standard treatments, employment of strict preventive measures and development of effective vaccines. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  19. Radiation enhanced reactivation of herpes simplex virus: effect of caffeine.

    Science.gov (United States)

    Hellman, K B; Lytle, C D; Bockstahler, L E

    1976-09-01

    Ultaviolet enhanced (Weigle) reactivation of UV-irradiated herpes simplex virus in UV-irradiated CV-1 monkey kidney cell monolayers was decreased by caffeine. X-ray enhanced reactivation of UV-irradiated virus in X-irradiated monolayers (X-ray reactivation) and UV- or X-ray-inactivated capacity of the cells to support unirradiated virus plaque formation were unaffected by caffeine. The results suggest that a caffeine-sensitive process is necessary for the expression of Weigle reactivation for herpes virus. Since cafeine did not significantly affect X-ray reactivation, different mechanisms may be responsible for the expression of Weigle reactivation and X-ray reactivation.

  20. Zika virus infection in immunocompetent pregnant mice causes fetal damage and placental pathology in the absence of fetal infection

    Science.gov (United States)

    Kummer, Lawrence W.; Lanthier, Paula; Kim, In-Jeong; Kuki, Atsuo; Thomas, Stephen J.

    2018-01-01

    Zika virus (ZIKV) infection during human pregnancy may cause diverse and serious congenital defects in the developing fetus. Previous efforts to generate animal models of human ZIKV infection and clinical symptoms often involved manipulating mice to impair their Type I interferon (IFN) signaling, thereby allowing enhanced infection and vertical transmission of virus to the embryo. Here, we show that even pregnant mice competent to generate Type I IFN responses that can limit ZIKV infection nonetheless develop profound placental pathology and high frequency of fetal demise. We consistently found that maternal ZIKV exposure led to placental pathology and that ZIKV RNA levels measured in maternal, placental or embryonic tissues were not predictive of the pathological effects seen in the embryos. Placental pathology included trophoblast hyperplasia in the labyrinth, trophoblast giant cell necrosis in the junctional zone, and loss of embryonic vessels. Our findings suggest that, in this context of limited infection, placental pathology rather than embryonic/fetal viral infection may be a stronger contributor to adverse pregnancy outcomes in mice. Our finding demonstrates that in immunocompetent mice, direct viral infection of the embryo is not essential for fetal demise. Our immunologically unmanipulated pregnancy mouse model provides a consistent and easily measurable congenital abnormality readout to assess fetal outcome, and may serve as an additional model to test prophylactic and therapeutic interventions to protect the fetus during pregnancy, and for studying the mechanisms of ZIKV congenital immunopathogenesis. PMID:29634758

  1. Human antibodies to the dengue virus E-dimer epitope have therapeutic activity against Zika virus infection.

    Science.gov (United States)

    Fernandez, Estefania; Dejnirattisai, Wanwisa; Cao, Bin; Scheaffer, Suzanne M; Supasa, Piyada; Wongwiwat, Wiyada; Esakky, Prabagaran; Drury, Andrea; Mongkolsapaya, Juthathip; Moley, Kelle H; Mysorekar, Indira U; Screaton, Gavin R; Diamond, Michael S

    2017-11-01

    The Zika virus (ZIKV) epidemic has resulted in congenital abnormalities in fetuses and neonates. Although some cross-reactive dengue virus (DENV)-specific antibodies can enhance ZIKV infection in mice, those recognizing the DENV E-dimer epitope (EDE) can neutralize ZIKV infection in cell culture. We evaluated the therapeutic activity of human monoclonal antibodies to DENV EDE for their ability to control ZIKV infection in the brains, testes, placentas, and fetuses of mice. A single dose of the EDE1-B10 antibody given 3 d after ZIKV infection protected against lethality, reduced ZIKV levels in brains and testes, and preserved sperm counts. In pregnant mice, wild-type or engineered LALA variants of EDE1-B10, which cannot engage Fcg receptors, diminished ZIKV burden in maternal and fetal tissues, and protected against fetal demise. Because neutralizing antibodies to EDE have therapeutic potential against ZIKV, in addition to their established inhibitory effects against DENV, it may be possible to develop therapies that control disease caused by both viruses.

  2. Leucine-rich repeat-containing G protein-coupled receptor 4 facilitates vesicular stomatitis virus infection by binding vesicular stomatitis virus glycoprotein.

    Science.gov (United States)

    Zhang, Na; Huang, Hongjun; Tan, Binghe; Wei, Yinglei; Xiong, Qingqing; Yan, Yan; Hou, Lili; Wu, Nannan; Siwko, Stefan; Cimarelli, Andrea; Xu, Jianrong; Han, Honghui; Qian, Min; Liu, Mingyao; Du, Bing

    2017-10-06

    Vesicular stomatitis virus (VSV) and rabies and Chandipura viruses belong to the Rhabdovirus family. VSV is a common laboratory virus to study viral evolution and host immune responses to viral infection, and recombinant VSV-based vectors have been widely used for viral oncolysis, vaccination, and gene therapy. Although the tropism of VSV is broad, and its envelope glycoprotein G is often used for pseudotyping other viruses, the host cellular components involved in VSV infection remain unclear. Here, we demonstrate that the host protein leucine-rich repeat-containing G protein-coupled receptor 4 (Lgr4) is essential for VSV and VSV-G pseudotyped lentivirus (VSVG-LV) to infect susceptible cells. Accordingly, Lgr4-deficient mice had dramatically decreased VSV levels in the olfactory bulb. Furthermore, Lgr4 knockdown in RAW 264.7 cells also significantly suppressed VSV infection, and Lgr4 overexpression in RAW 264.7 cells enhanced VSV infection. Interestingly, only VSV infection relied on Lgr4, whereas infections with Newcastle disease virus, influenza A virus (A/WSN/33), and herpes simplex virus were unaffected by Lgr4 status. Of note, assays of virus entry, cell ELISA, immunoprecipitation, and surface plasmon resonance indicated that VSV bound susceptible cells via the Lgr4 extracellular domain. Pretreating cells with an Lgr4 antibody, soluble LGR4 extracellular domain, or R-spondin 1 blocked VSV infection by competitively inhibiting VSV binding to Lgr4. Taken together, the identification of Lgr4 as a VSV-specific host factor provides important insights into understanding VSV entry and its pathogenesis and lays the foundation for VSV-based gene therapy and viral oncolytic therapeutics. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  3. Genital herpes simplex virus infections in adults.

    Science.gov (United States)

    Mertz, G; Corey, L

    1984-02-01

    With the decline in prevalence of childhood-acquired oral-labial herpes simplex type 1 infections in some populations and the increasing incidence of genital herpes infections in adults, clinicians are more likely to see patients with severe primary, first-episode genital herpes infections. Complications of these primary infections may include aseptic meningitis and urine retention secondary to sacral radiculopathy or autonomic dysfunction. Presented are the clinical course of first-episode and recurrent infections, complications, diagnostic laboratory methods, and results of controlled clinical trials evaluating the efficacy of topical, intravenous, and oral preparations of acyclovir.

  4. Transmission potential of Zika virus infection in the South Pacific.

    Science.gov (United States)

    Nishiura, Hiroshi; Kinoshita, Ryo; Mizumoto, Kenji; Yasuda, Yohei; Nah, Kyeongah

    2016-04-01

    Zika virus has spread internationally through countries in the South Pacific and Americas. The present study aimed to estimate the basic reproduction number, R0, of Zika virus infection as a measurement of the transmission potential, reanalyzing past epidemic data from the South Pacific. Incidence data from two epidemics, one on Yap Island, Federal State of Micronesia in 2007 and the other in French Polynesia in 2013-2014, were reanalyzed. R0 of Zika virus infection was estimated from the early exponential growth rate of these two epidemics. The maximum likelihood estimate (MLE) of R0 for the Yap Island epidemic was in the order of 4.3-5.8 with broad uncertainty bounds due to the small sample size of confirmed and probable cases. The MLE of R0 for French Polynesia based on syndromic data ranged from 1.8 to 2.0 with narrow uncertainty bounds. The transmissibility of Zika virus infection appears to be comparable to those of dengue and chikungunya viruses. Considering that Aedes species are a shared vector, this finding indicates that Zika virus replication within the vector is perhaps comparable to dengue and chikungunya. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  5. Possible Association Between Zika Virus Infection and Microcephaly - Brazil, 2015.

    Science.gov (United States)

    Schuler-Faccini, Lavinia; Ribeiro, Erlane M; Feitosa, Ian M L; Horovitz, Dafne D G; Cavalcanti, Denise P; Pessoa, André; Doriqui, Maria Juliana R; Neri, Joao Ivanildo; Neto, Joao Monteiro de Pina; Wanderley, Hector Y C; Cernach, Mirlene; El-Husny, Antonette S; Pone, Marcos V S; Serao, Cassio L C; Sanseverino, Maria Teresa V

    2016-01-29

    In early 2015, an outbreak of Zika virus, a flavivirus transmitted by Aedes mosquitoes, was identified in northeast Brazil, an area where dengue virus was also circulating. By September, reports of an increase in the number of infants born with microcephaly in Zika virus-affected areas began to emerge, and Zika virus RNA was identified in the amniotic fluid of two women whose fetuses had been found to have microcephaly by prenatal ultrasound. The Brazil Ministry of Health (MoH) established a task force to investigate the possible association of microcephaly with Zika virus infection during pregnancy and a registry for incident microcephaly cases (head circumference ≥2 standard deviations [SD] below the mean for sex and gestational age at birth) and pregnancy outcomes among women suspected to have had Zika virus infection during pregnancy. Among a cohort of 35 infants with microcephaly born during August-October 2015 in eight of Brazil's 26 states and reported to the registry, the mothers of all 35 had lived in or visited Zika virus-affected areas during pregnancy, 25 (71%) infants had severe microcephaly (head circumference >3 SD below the mean for sex and gestational age), 17 (49%) had at least one neurologic abnormality, and among 27 infants who had neuroimaging studies, all had abnormalities. Tests for other congenital infections were negative. All infants had a lumbar puncture as part of the evaluation and cerebrospinal fluid (CSF) samples were sent to a reference laboratory in Brazil for Zika virus testing; results are not yet available. Further studies are needed to confirm the association of microcephaly with Zika virus infection during pregnancy and to understand any other adverse pregnancy outcomes associated with Zika virus infection. Pregnant women in Zika virus-affected areas should protect themselves from mosquito bites by using air conditioning, screens, or nets when indoors, wearing long sleeves and pants, using permethrin-treated clothing and gear

  6. Memory CD8 T cells mediate severe immunopathology following respiratory syncytial virus infection.

    Directory of Open Access Journals (Sweden)

    Megan E Schmidt

    2018-01-01

    Full Text Available Memory CD8 T cells can provide protection from re-infection by respiratory viruses such as influenza and SARS. However, the relative contribution of memory CD8 T cells in providing protection against respiratory syncytial virus (RSV infection is currently unclear. To address this knowledge gap, we utilized a prime-boost immunization approach to induce robust memory CD8 T cell responses in the absence of RSV-specific CD4 T cells and antibodies. Unexpectedly, RSV infection of mice with pre-existing CD8 T cell memory led to exacerbated weight loss, pulmonary disease, and lethal immunopathology. The exacerbated disease in immunized mice was not epitope-dependent and occurred despite a significant reduction in RSV viral titers. In addition, the lethal immunopathology was unique to the context of an RSV infection as mice were protected from a normally lethal challenge with a recombinant influenza virus expressing an RSV epitope. Memory CD8 T cells rapidly produced IFN-γ following RSV infection resulting in elevated protein levels in the lung and periphery. Neutralization of IFN-γ in the respiratory tract reduced morbidity and prevented mortality. These results demonstrate that in contrast to other respiratory viruses, RSV-specific memory CD8 T cells can induce lethal immunopathology despite mediating enhanced viral clearance.

  7. Enhanced capacity of DNA repair in human cytomegalovirus-infected cells

    International Nuclear Information System (INIS)

    Nishiyama, Y.; Rapp, F.

    1981-01-01

    Plaque formation in Vero cells by UV-irradiated herpes simplex virus was enhanced by infection with human cytomegalovirus (HCMV), UV irradiation, or treatment with methylmethanesulfonate. Preinfection of Vero cells with HCMV enhanced reactivation of UV-irradiated herpes simplex virus more significantly than did treatment with UV or methylmethanesulfonate alone. A similar enhancement by HCMV was observed in human embryonic fibroblasts, but not in xeroderma pigmentosum (XP12BE) cells. It was also found that HCMV infection enhanced hydroxyurea-resistant DNA synthesis induced by UV light or methylmethanesulfonate. Alkaline sucrose gradient sedimentation analysis revealed an enhanced rate of synthesis of all size classes of DNA in UV-irradiated HCMV-infected Vero cells. However, HCMV infection did not induce repairable lesions in cellular DNA and did not significantly inhibit host cell DNA synthesis, unlike UV or methylmethanesulfonate. These results indicate that HCMV enhanced DNA repair capacity in the host cells without producing detectable lesions in cellular DNA and without inhibiting DNA synthesis. This repair appeared to be error proof for UV-damaged herpes simplex virus DNA when tested with herpes simplex virus thymidine kinase-negative mutants

  8. Seroepidemiology of Asymptomatic Dengue Virus Infection in Jeddah, Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Ghazi A. Jamjoom

    2016-01-01

    Full Text Available Background Although virologically confirmed dengue fever has been recognized in Jeddah, Saudi Arabia, since 1994, causing yearly outbreaks, no proper seroepidemiologic studies on dengue virus have been conducted in this region. Such studies can define the extent of infection by this virus and estimate the proportion that may result in disease. The aim of this study was to measure the seroprevalence of past dengue virus infection in healthy Saudi nationals from different areas in the city of Jeddah and to investigate demographic and environmental factors that may increase exposure to infection. Methods Sera were collected from 1984 Saudi subjects attending primary health care centers in six districts of Jeddah. These included general patients of various ages seeking routine vaccinations, antenatal care or treatment of different illnesses excluding fever or suspected dengue. A number of blood donors were also tested. Serum samples were tested by enzyme immunoassay (EIA for IgG antibodies to dengue viruses 1, 2, 3, 4. A questionnaire was completed for each patient recording various anthropometric data and factors that may indicate possible risk of exposure to mosquito bites and dengue infection. Patients with missing data and those who reported a history of dengue fever were excluded from analysis, resulting in a sample of 1939 patients to be analyzed. Results The overall prevalence of dengue virus infection as measured by anti-dengue IgG antibodies from asymptomatic residents in Jeddah was 47.8% (927/1939 and 37% (68/184 in blood donors. Infection mostly did not result in recognizable disease, as only 19 of 1956 subjects with complete information (0.1% reported having dengue fever in the past. Anti dengue seropositivity increased with age and was higher in males than females and in residents of communal housing and multistory buildings than in villas. One of the six districts showed significant increase in exposure rate as compared to the others

  9. Clinical signs, diagnosis, and case reports of Vaccinia virus infections

    Directory of Open Access Journals (Sweden)

    Daniela Carla Medeiros Silva

    Full Text Available Vaccinia virus is responsible for a zoonosis that usually affects cattle and human beings in Brazil. The initial clinical signs of the infection are focal red skin areas, fever, and general symptoms similar to those of a cold. Then, pustules and ulcerated lesions surrounded by edema and erythema follow, as well as local lymphadenopathy that can last for weeks. Cure and healing of the lesions occur over several weeks, leaving a typical scar in the skin of people and animals affected. The infection definitive diagnosis is made through morphological characterization of the virus by use of electron microscopy, followed by PCR for specific viral genes. Since 1963, circulating orthopoxviruses in infectious outbreaks in several regions of Brazil have been reported. Later, the etiological agent of those infections was characterized as samples of Vaccinia virus. In addition, the widespread use of those viruses in research laboratories and mass vaccination of militaries have contributed to increase the cases of those infections worldwide. Thus, several epidemiological and clinical studies are required, as well as studies of viral immunology, public health, and economic impact, because little is known about those Vaccinia virus outbreaks in Brazil.

  10. Insights into Head-Tailed Viruses Infecting Extremely Halophilic Archaea

    Science.gov (United States)

    Pietilä, Maija K.; Laurinmäki, Pasi; Russell, Daniel A.; Ko, Ching-Chung; Jacobs-Sera, Deborah; Butcher, Sarah J.

    2013-01-01

    Extremophilic archaea, both hyperthermophiles and halophiles, dominate in habitats where rather harsh conditions are encountered. Like all other organisms, archaeal cells are susceptible to viral infections, and to date, about 100 archaeal viruses have been described. Among them, there are extraordinary virion morphologies as well as the common head-tailed viruses. Although approximately half of the isolated archaeal viruses belong to the latter group, no three-dimensional virion structures of these head-tailed viruses are available. Thus, rigorous comparisons with bacteriophages are not yet warranted. In the present study, we determined the genome sequences of two of such viruses of halophiles and solved their capsid structures by cryo-electron microscopy and three-dimensional image reconstruction. We show that these viruses are inactivated, yet remain intact, at low salinity and that their infectivity is regained when high salinity is restored. This enabled us to determine their three-dimensional capsid structures at low salinity to a ∼10-Å resolution. The genetic and structural data showed that both viruses belong to the same T-number class, but one of them has enlarged its capsid to accommodate a larger genome than typically associated with a T=7 capsid by inserting an additional protein into the capsid lattice. PMID:23283946

  11. Nosocomial infections by respiratory syncytial virus in children

    Directory of Open Access Journals (Sweden)

    Maren Karina Machado Echeverría

    2017-01-01

    Full Text Available Introduction: Acute lower respiratory infections cause high morbidity and mortality in children. Respiratory syncytial virus (RSV is the most prevalent agent. Some viruses cause serious nosocomial infections. In Uruguay, there is no knowledge about the morbidity and mortality of nosocomial infections by RSV. Objective: To determine the prevalence and characteristics of RSV nosocomial infections. Methodology: A descriptive study of acute lower respiratory infections caused by RSV in patients younger than two years, between 1/1/2005 and 31/12/2008 at the Hospital Pediátrico del Centro Hospitalario Pereira Rossell, was made. Results: Were identified 59 patients who represented an annual rate lower than 2/1000 discharges. The monthly distribution of cases was similar to the respiratory infections. No outbreaks were reported. The age of the patients had an average of 8.9 months, 39 were younger than one year, 23 had one or more risk factors for severe disease. Six patients required admission to intensive care unit, all required invasive ventilation, 3 died, none had chronic respiratory failure following the RSV nosocomial infection. Conclusions: During the study period, the RSV nosocomial infections showed a low prevalence, despite it highly contagiousness. They mainly affected young children, carriers of risk factors for severe ALRI. Their evolution was similar to that reported for RSV respiratory infections community acquired. It is important to maintain standards for the control of nosocomial infections, to prevent nosocomial transmission of RSV and prevent the onset of severe disease in hospitalized patients.

  12. Nonhuman Primate Models of Hepatitis A Virus and Hepatitis E Virus Infections.

    Science.gov (United States)

    Lanford, Robert E; Walker, Christopher M; Lemon, Stanley M

    2018-04-23

    Although phylogenetically unrelated, human hepatitis viruses share an exclusive or near exclusive tropism for replication in differentiated hepatocytes. This narrow tissue tropism may contribute to the restriction of the host ranges of these viruses to relatively few host species, mostly nonhuman primates. Nonhuman primate models thus figure prominently in our current understanding of the replication and pathogenesis of these viruses, including the enterically transmitted hepatitis A virus (HAV) and hepatitis E virus (HEV), and have also played major roles in vaccine development. This review draws comparisons of HAV and HEV infection from studies conducted in nonhuman primates, and describes how such studies have contributed to our current understanding of the biology of these viruses. Copyright © 2018 Cold Spring Harbor Laboratory Press; all rights reserved.

  13. Virus-like particle vaccine primes immune responses preventing inactivated-virus vaccine-enhanced disease against respiratory syncytial virus.

    Science.gov (United States)

    Hwang, Hye Suk; Lee, Young-Tae; Kim, Ki-Hye; Ko, Eun-Ju; Lee, Youri; Kwon, Young-Man; Kang, Sang-Moo

    2017-11-01

    Formalin inactivated respiratory syncytial virus (FI-RSV) vaccination caused vaccine-enhanced respiratory disease (ERD) upon exposure to RSV in children. Virus-like particles presenting RSV F fusion protein (F VLP) are known to increase T helper type-1 (Th1) immune responses and avoid ERD in animal models. We hypothesized that F VLP would prime immune responses preventing ERD upon subsequent exposure to ERD-prone FI-RSV. Here, we demonstrated that heterologous F VLP priming and FI-RSV boosting of mice prevented FI-RSV vaccine-enhanced lung inflammation and eosinophilia upon RSV challenge. F VLP priming redirected pulmonary T cells toward effector CD8 T cells producing Th1 cytokines and significantly suppressed pulmonary Th2 cytokines. This study suggests that RSV F VLP priming would modulate and shift immune responses to subsequent exposure to ERD-prone FI-RSV vaccine and RSV infection, suppressing Th2 immune-mediated pulmonary histopathology and eosinophilia. Copyright © 2017. Published by Elsevier Inc.

  14. Tahyna virus genetics, infectivity, and immunogenicity in mice and monkeys

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    Whitehead Stephen S

    2011-03-01

    Full Text Available Abstract Background Tahyna virus (TAHV is a human pathogen of the California encephalitis virus (CEV serogroup (Bunyaviridae endemic to Europe, Asia, and Africa. TAHV maintains an enzootic life cycle with several species of mosquito vectors and hares, rabbits, hedgehogs, and rodents serving as small mammal amplifying hosts. Human TAHV infection occurs in summer and early fall with symptoms of fever, headache, malaise, conjunctivitis, pharyngitis, and nausea. TAHV disease can progress to CNS involvement, although unlike related La Crosse virus (LACV, fatalities have not been reported. Human infections are frequent with neutralizing antibodies present in 60-80% of the elderly population in endemic areas. Results In order to determine the genomic sequence of wild-type TAHV, we chose three TAHV isolates collected over a 26-year period from mosquitoes. Here we present the first complete sequence of the TAHV S, M, and L segments. The three TAHV isolates maintained a highly conserved genome with both nucleotide and amino acid sequence identity greater than 99%. In order to determine the extent of genetic relatedness to other members of the CEV serogroup, we compared protein sequences of TAHV with LACV, Snowshoe Hare virus (SSHV, Jamestown Canyon virus (JCV, and Inkoo virus (INKV. By amino acid comparison, TAHV was most similar to SSHV followed by LACV, JCV, and INKV. The sequence of the GN protein is most conserved followed by L, N, GC, NSS, and NSM. In a weanling Swiss Webster mouse model, all three TAHV isolates were uniformly neurovirulent, but only one virus was neuroinvasive. In rhesus monkeys, the virus was highly immunogenic even in the absence of viremia. Cross neutralization studies utilizing monkey immune serum demonstrated that TAHV is antigenically distinct from North American viruses LACV and JCV. Conclusions Here we report the first complete sequence of TAHV and present genetic analysis of new-world viruses, LACV, SSHV, and JCV with old

  15. Preparedness for ongoing Ebola virus infection: how to welcome it?

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    Sora Yasri

    2015-06-01

    Full Text Available The problem of Ebola virus infection is the big global concern. Preparedness for ongoing Ebola virus infection is the topic that should be discussed. In fact, it is necessary to set up a biosecurity system to protect against the present Ebola outbreak. The medical personnel have to prepare for fighting the problem. The management of the present outbreak requires international collaboration and control of cross-border disease transmission is also the big challenge. The good case study is the Hajj scenario.

  16. Beet western yellows virus infects the carnivorous plant Nepenthes mirabilis.

    Science.gov (United States)

    Miguel, Sissi; Biteau, Flore; Mignard, Benoit; Marais, Armelle; Candresse, Thierry; Theil, Sébastien; Bourgaud, Frédéric; Hehn, Alain

    2016-08-01

    Although poleroviruses are known to infect a broad range of higher plants, carnivorous plants have not yet been reported as hosts. Here, we describe the first polerovirus naturally infecting the pitcher plant Nepenthes mirabilis. The virus was identified through bioinformatic analysis of NGS transcriptome data. The complete viral genome sequence was assembled from overlapping PCR fragments and shown to share 91.1 % nucleotide sequence identity with the US isolate of beet western yellows virus (BWYV). Further analysis of other N. mirabilis plants revealed the presence of additional BWYV isolates differing by several insertion/deletion mutations in ORF5.

  17. Immune regulation in chronic hepatitis C virus infection

    DEFF Research Database (Denmark)

    Hartling, Hans Jakob; Ballegaard, Vibe Cecilie; Nielsen, Nick Schou

    2016-01-01

    The immunological result of infection with Hepatitis C virus (HCV) depends on the delicate balance between a vigorous immune response that may clear the infection, but with a risk of unspecific inflammation and, or a less inflammatory response that leads to chronic infection. In general, exhaustion...... and impairment of cytotoxic function of HCV-specific T cells and NK cells are found in patients with chronic HCV infection. In contrast, an increase in immune regulatory functions is found primarily in form of increased IL-10 production possibly due to increased level and function of anti-inflammatory Tregs...

  18. Advances in the Treatment of Human Immunodeficiency Virus and Hepatitis B Virus Co-infection

    Directory of Open Access Journals (Sweden)

    Sun Guofang

    2016-06-01

    Full Text Available Hepatitis B virus (HBV and human immunodeficiency virus (HIV are transmitted through the same pathways. Therefore, the incidence of HBV in the HIV-infected population is higher than that in the healthy population, and is more obvious in China given the high HBV prevalence in the country. HIV and HBV co-infection can accelerate the disease process of HBV. Moreover, the incidence of cirrhosis and end-stage liver disease is higher in patients co-infected with HIV and HBV than in patients infected HBV alone. When treating patients co-infected with HIV and HBV for HBV infection alone, care should be taken to avoid the induction of HIV resistance. HBV should be considered during drug selection for anti-retroviral treatment. Furthermore, the effective HBV treatment should be retained if anti-retroviral drugs require changing.

  19. Herpes Simplex Virus Infections of the Central Nervous System.

    Science.gov (United States)

    Whitley, Richard J

    2015-12-01

    This article summarizes knowledge of herpes simplex virus (HSV) infections of the central nervous system (CNS). Disease pathogenesis, detection of DNA polymerase chain reaction (PCR) for diagnosis and prognosis, and approaches to therapy warrant consideration. HSV infection of the CNS is one of few treatable viral diseases. Clinical trials indicate that outcome following neonatal herpes simplex virus type 2 (HSV-2) infections of the CNS is significantly improved when 6 months of suppressive oral acyclovir therapy follows IV antiviral therapy. In contrast, herpes simplex virus type 1 (HSV-1) infections of the brain do not benefit from extended oral antiviral therapy. This implies a difference in disease pathogenesis between HSV-2 and HSV-1 infections of the brain. PCR detection of viral DNA in the CSF is the gold standard for diagnosis. Use of PCR is now being adopted as a basis for determining the duration of therapy in the newborn. HSV infections are among the most common encountered by humans; seropositivity occurs in 50% to 90% of adult populations. Herpes simplex encephalitis, however, is an uncommon result of this infection. Since no new antiviral drugs have been introduced in nearly 3 decades, much effort has focused on learning how to better use acyclovir and how to use existing databases to establish earlier diagnosis.

  20. Advances in Animal Models of Hepatitis B Virus Infection

    Directory of Open Access Journals (Sweden)

    Zhang Hang

    2015-12-01

    Full Text Available Hepatitis B virus (HBV infection seriously affects human health. Stable and reliable animal models of HBV infection bear significance in studying pathogenesis of this health condition and development of intervention measures. HBV exhibits high specificity for hosts, and chimpanzee is long used as sole animal model of HBV infection. However, use of chimpanzees is strictly constrained because of ethical reasons. Many methods were used to establish small-animal models of HBV infection. Tupaia is the only nonprimate animal that can be infected by HBV. Use of HBV-related duck hepatitis virus and marmot hepatitis virus infection model contributed to evaluation of mechanism of HBV replication and HBV treatment methods. In recent years, development of human–mouse chimeric model provided possibility of using common experimental animals to carry out HBV research. These models feature their own advantages and disadvantages and can be complementary in some ways. This study provides an overview of current and commonly used animal models of HBV infection.

  1. Negative-strand RNA viruses: the plant-infecting counterparts.

    Science.gov (United States)

    Kormelink, Richard; Garcia, Maria Laura; Goodin, Michael; Sasaya, Takahide; Haenni, Anne-Lise

    2011-12-01

    While a large number of negative-strand (-)RNA viruses infect animals and humans, a relative small number have plants as their primary host. Some of these have been classified within families together with animal/human infecting viruses due to similarities in particle morphology and genome organization, while others have just recently been/or are still classified in floating genera. In most cases, at least two striking differences can still be discerned between the animal/human-infecting viruses and their plant-infecting counterparts which for the latter relate to their adaptation to plants as hosts. The first one is the capacity to modify plasmodesmata to facilitate systemic spread of infectious viral entities throughout the plant host. The second one is the capacity to counteract RNA interference (RNAi, also referred to as RNA silencing), the innate antiviral defence system of plants and insects. In this review an overview will be presented on the negative-strand RNA plant viruses classified within the families Bunyaviridae, Rhabdoviridae, Ophioviridae and floating genera Tenuivirus and Varicosavirus. Genetic differences with the animal-infecting counterparts and their evolutionary descendants will be described in light of the above processes. Copyright © 2011 Elsevier B.V. All rights reserved.

  2. Tacaribe virus but not junin virus infection induces cytokine release from primary human monocytes and macrophages.

    Directory of Open Access Journals (Sweden)

    Allison Groseth

    Full Text Available The mechanisms underlying the development of disease during arenavirus infection are poorly understood. However, common to all hemorrhagic fever diseases is the involvement of macrophages as primary target cells, suggesting that the immune response in these cells may be of paramount importance during infection. Thus, in order to identify features of the immune response that contribute to arenavirus pathogenesis, we have examined the growth kinetics and cytokine profiles of two closely related New World arenaviruses, the apathogenic Tacaribe virus (TCRV and the hemorrhagic fever-causing Junin virus (JUNV, in primary human monocytes and macrophages. Both viruses grew robustly in VeroE6 cells; however, TCRV titres were decreased by approximately 10 fold compared to JUNV in both monocytes and macrophages. Infection of both monocytes and macrophages with TCRV also resulted in the release of high levels of IL-6, IL-10 and TNF-α, while levels of IFN-α, IFN-β and IL-12 were not affected. However, we could show that the presence of these cytokines had no direct effect on growth of either TCRV of JUNV in macrophages. Further analysis also showed that while the production of IL-6 and IL-10 are dependent on viral replication, production of TNF-α also occurs after exposure to UV-inactivated TCRV particles and is thus independent of productive virus infection. Surprisingly, JUNV infection did not have an effect on any of the cytokines examined indicating that, in contrast to other viral hemorrhagic fever viruses, macrophage-derived cytokine production is unlikely to play an active role in contributing to the cytokine dysregulation observed in JUNV infected patients. Rather, these results suggest that an early, controlled immune response by infected macrophages may be critical for the successful control of infection of apathogenic viruses and prevention of subsequent disease, including systemic cytokine dysregulation.

  3. Immunology and Pathology of Arena Virus Infections.

    Science.gov (United States)

    1992-04-15

    the 15 guinea pigs infected with the attenuated strain (PIC3739) had measurable TNF at any time during the course. Mean serum TNF levels for adPIC...inherent replication advantage in adPIC or increased efficiency of natural immunity against the attenuated strain PIC3739. Significant changes in...Direct infection of T cells may cause frank cytolysis with induction of lymphopenia, as in parvovirus or HIV-l infections; alternatively, in non

  4. Ganjam virus/Nairobi sheep disease virus induces a pro-inflammatory response in infected sheep

    Directory of Open Access Journals (Sweden)

    bin Tarif Abid

    2012-10-01

    Full Text Available Abstract Partly due to climate change, and partly due to changes of human habitat occupation, the impact of tick-borne viruses is increasing. Nairobi sheep disease virus (NSDV and Ganjam virus (GV are two names for the same virus, which causes disease in sheep and goats and is currently known to be circulating in India and East Africa. The virus is transmitted by ixodid ticks and causes a severe hemorrhagic disease. We have developed a real-time PCR assay for the virus genome and validated it in a pilot study of the pathogenicity induced by two different isolates of NSDV/GV. One isolate was highly adapted to tissue culture, grew in most cell lines tested, and was essentially apathogenic in sheep. The second isolate appeared to be poorly adapted to cell culture and retained pathogenicity in sheep. The real-time PCR assay for virus easily detected 4 copies or less of the viral genome, and allowed a quantitative measure of the virus in whole blood. Measurement of the changes in cytokine mRNAs showed similar changes to those observed in humans infected by the closely related virus Crimean Congo hemorrhagic fever virus.

  5. Ganjam virus/Nairobi sheep disease virus induces a pro-inflammatory response in infected sheep.

    Science.gov (United States)

    Bin Tarif, Abid; Lasecka, Lidia; Holzer, Barbara; Baron, Michael D

    2012-10-19

    Partly due to climate change, and partly due to changes of human habitat occupation, the impact of tick-borne viruses is increasing. Nairobi sheep disease virus (NSDV) and Ganjam virus (GV) are two names for the same virus, which causes disease in sheep and goats and is currently known to be circulating in India and East Africa. The virus is transmitted by ixodid ticks and causes a severe hemorrhagic disease. We have developed a real-time PCR assay for the virus genome and validated it in a pilot study of the pathogenicity induced by two different isolates of NSDV/GV. One isolate was highly adapted to tissue culture, grew in most cell lines tested, and was essentially apathogenic in sheep. The second isolate appeared to be poorly adapted to cell culture and retained pathogenicity in sheep. The real-time PCR assay for virus easily detected 4 copies or less of the viral genome, and allowed a quantitative measure of the virus in whole blood. Measurement of the changes in cytokine mRNAs showed similar changes to those observed in humans infected by the closely related virus Crimean Congo hemorrhagic fever virus.

  6. Treatment of chronic Hepatitis B virus infection

    OpenAIRE

    Carreño, N.; Moreno, D.; Sangro, B.

    2004-01-01

    El tratamiento del paciente con hepatitis crónica por virus B (VHB) debe realizarse bajo el conocimiento de que el porcentaje de pacientes infectados por el virus B que desarrollan hepatitis crónica se mantiene entre el 5-10%. De ellos, el 10-30% presentarán infección crónica con replicación viral activa, lesión hepática necroinflamatoria, evolución a cirrosis hepática y riesgo de desarrollar hepatocarcinoma. Por este motivo la meta del tratamiento es lograr la negativización del HBeAg, la se...

  7. Prevalence of asymptomatic Zika virus infection: a systematic review

    Science.gov (United States)

    Pinart, Mariona; Elias, Vanessa; Reveiz, Ludovic

    2018-01-01

    Abstract Objective To conduct a systematic review to estimate the prevalence of asymptomatic Zika virus infection in the general population and in specific population groups. Methods We searched PubMed®, Embase® and LILACS online databases from inception to 26 January 2018. We included observational epidemiological studies where laboratory testing was used to confirm positive exposure of participants to Zika virus and in which Zika virus symptom status was also recorded. We excluded studies in which having symptoms of Zika virus was a criterion for inclusion. The main outcome assessed was percentage of all Zika virus-positive participants who were asymptomatic. We used a quality-effects approach and the double arcsine transformation for the meta-analysis. Findings We assessed 753 studies for inclusion, of which 23 were included in the meta-analysis, totalling 11 305 Zika virus-positive participants. The high degree of heterogeneity in the studies (I2 = 99%) suggests that the pooled prevalence of asymptomatic Zika virus-positive participants was probably not a robust estimate. Analysis based on subgroups of the population (general population, returned travellers, blood donors, adults with Guillain–Barré syndrome, pregnant women and babies with microcephaly) was not able to explain the heterogeneity. Funnel and Doi plots showed major asymmetry, suggesting selection bias or true heterogeneity. Conclusion Better-quality research is needed, using standardized methods, to determine the true prevalence of asymptomatic Zika virus and whether it varies between populations or over time. PMID:29904223

  8. Autophagy interaction with herpes simplex virus type-1 infection

    Science.gov (United States)

    O'Connell, Douglas; Liang, Chengyu

    2016-01-01

    abstract More than 50% of the U.S. population is infected with herpes simplex virus type-I (HSV-1) and global infectious estimates are nearly 90%. HSV-1 is normally seen as a harmless virus but debilitating diseases can arise, including encephalitis and ocular diseases. HSV-1 is unique in that it can undermine host defenses and establish lifelong infection in neurons. Viral reactivation from latency may allow HSV-1 to lay siege to the brain (Herpes encephalitis). Recent advances maintain that HSV-1 proteins act to suppress and/or control the lysosome-dependent degradation pathway of macroautophagy (hereafter autophagy) and consequently, in neurons, may be coupled with the advancement of HSV-1-associated pathogenesis. Furthermore, increasing evidence suggests that HSV-1 infection may constitute a gradual risk factor for neurodegenerative disorders. The relationship between HSV-1 infection and autophagy manipulation combined with neuropathogenesis may be intimately intertwined demanding further investigation. PMID:26934628

  9. Hepatitis A and E virus infections among children in Mongolia.

    Science.gov (United States)

    Davaalkham, Dambadarjaa; Enkhoyun, Tsogzolbaatar; Takahashi, Masaharu; Nakamura, Yosikazu; Okamoto, Hiroaki

    2009-08-01

    To compare the epidemiologic profiles of hepatitis A virus (HAV) and hepatitis E virus (HEV) infections in children in Mongolia, the prevalence of HAV and HEV infections was studied serologically and molecularly among 520 apparently healthy children 7-12 years of age (mean +/- standard deviation, 8.5 +/- 0.8 years) using serum samples obtained in 2004. Total antibody against HAV (anti-HAV) was detected in 438 children (84.2%), whereas IgG antibody against HEV (anti-HEV IgG) was detected in only three subjects (0.6%). All three subjects with anti-HEV IgG were negative for anti-HEV IgM and HEV RNA. The presence of HAV RNA was tested in all 520 subjects, and one child (9-year-old girl) was found to have detectable HAV RNA (subgenotype IA). In conclusion, HEV infection was uncommon, but subclinical HAV infection was highly prevalent among children in Mongolia.

  10. Transcriptome analysis of feline infectious peritonitis virus infection.

    Science.gov (United States)

    Mehrbod, Parvaneh; Harun, Mohammad Syamsul Reza; Shuid, Ahmad Naqib; Omar, Abdul Rahman

    2015-01-01

    Feline infectious peritonitis (FIP) is a lethal systemic disease caused by FIP virus (FIPV). There are no effective vaccines or treatment available, and the virus virulence determinants and pathogenesis are not fully understood. Here, we describe the sequencing of RNA extracted from Crandell Rees Feline Kidney (CRFK) cells infected with FIPV using the Illumina next-generation sequencing approach. Bioinformatics analysis, based on Felis catus 2X annotated shotgun reference genome, using CLC bio Genome Workbench is used to map both control and infected cells. Kal's Z test statistical analysis is used to analyze the differentially expressed genes from the infected CRFK cells. In addition, RT-qPCR analysis is used for further transcriptional profiling of selected genes in infected CRFK cells and Peripheral Blood Mononuclear Cells (PBMCs) from healthy and FIP-diagnosed cats.

  11. Epstein-Barr virus infection and nasopharyngeal carcinoma.

    Science.gov (United States)

    Tsao, Sai Wah; Tsang, Chi Man; Lo, Kwok Wai

    2017-10-19

    Epstein-Barr virus (EBV) is associated with multiple types of human cancer, including lymphoid and epithelial cancers. The closest association with EBV infection is seen in undifferentiated nasopharyngeal carcinoma (NPC), which is endemic in the southern Chinese population. A strong association between NPC risk and the HLA locus at chromosome 6p has been identified, indicating a link between the presentation of EBV antigens to host immune cells and NPC risk. EBV infection in NPC is clonal in origin, strongly suggesting that NPC develops from the clonal expansion of a single EBV-infected cell. In epithelial cells, the default program of EBV infection is lytic replication. However, latent infection is the predominant mode of EBV infection in NPC. The establishment of latent EBV infection in pre-invasive nasopharyngeal epithelium is believed to be an early stage of NPC pathogenesis. Recent genomic study of NPC has identified multiple somatic mutations in the upstream negative regulators of NF-κB signalling. Dysregulated NF-κB signalling may contribute to the establishment of latent EBV infection in NPC. Stable EBV infection and the expression of latent EBV genes are postulated to drive the transformation of pre-invasive nasopharyngeal epithelial cells to cancer cells through multiple pathways.This article is part of the themed issue 'Human oncogenic viruses'. © 2017 The Author(s).

  12. Four viruses infecting figs in Western Saudi Arabia

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    Amal Y. ALDHEBIANI

    2015-12-01

    Full Text Available Many diseases are compromising fig production in Saudi Arabia and in particular those caused by viruses. RT-PCR assays were conducted on 80 samples collected from four fig-growing provinces in the West Mecca region of Saudi Arabia, including the Fatima, Khulais, Rabigh and Alshifa valleys. Samples consisted of leaf tissues taken from caprifig and common fig trees. The presence of Fig mosaic virus (FMV, Fig leaf mottle-associated virus 1 (FLMaV-1, Fig leaf mottle-associated virus 2 (FLMaV-2 and Fig mild mottle-associated virus (FMMaV was assessed from the samples. RT-PCR results showed that all four viruses were present in the surveyed areas with different proportions of infection. Incidence was 69% of samples, with a peak of 80%, from the Alshifa and Fatima valleys, 60% from Rabigh and 55% from Khulais valley. FLMaV-1 was the prevailing virus (55% of samples, followed by FMV (34%, whereas FLMaV-2 (11% of samples and FMMaV (6% were less common. Most of the mosaic symptoms observed in surveyed fig orchards occurred with the presence of FMV. However, many other symptoms remained unexplained because of the arduous task of determining the involvement of other fig-infecting viruses with mosaic disease. This is the first report of FMMaV and FLMaV-2 in Saudi Arabia, and of FMV and FLMaV-1 in western Saudi Arabia. The virus status of this crop is probably compromised and a sanitation programme is required to produce healthy plant material in Saudi Arabia.

  13. Host cell responses to dengue virus infection

    NARCIS (Netherlands)

    Diosa Toro, Mayra

    2017-01-01

    Dengue (ook wel knokkelkoorts) is de meest voorkomende virale infectieziekte dat wordt overgedragen door muggen in de wereld met naar schatting 390 miljoen infecties per jaar. Ondanks de grote klinische impact en economische schade van het dengue virus is er nog steeds geen behandeling beschikbaar.

  14. Influenza A virus alters pneumococcal nasal colonization and middle ear infection independently of phase variation.

    Science.gov (United States)

    Wren, John T; Blevins, Lance K; Pang, Bing; King, Lauren B; Perez, Antonia C; Murrah, Kyle A; Reimche, Jennifer L; Alexander-Miller, Martha A; Swords, W Edward

    2014-11-01

    Streptococcus pneumoniae (pneumococcus) is both a widespread nasal colonizer and a leading cause of otitis media, one of the most common diseases of childhood. Pneumococcal phase variation influences both colonization and disease and thus has been linked to the bacteria's transition from colonizer to otopathogen. Further contributing to this transition, coinfection with influenza A virus has been strongly associated epidemiologically with the dissemination of pneumococci from the nasopharynx to the middle ear. Using a mouse infection model, we demonstrated that coinfection with influenza virus and pneumococci enhanced both colonization and inflammatory responses within the nasopharynx and middle ear chamber. Coinfection studies were also performed using pneumococcal populations enriched for opaque or transparent phase variants. As shown previously, opaque variants were less able to colonize the nasopharynx. In vitro, this phase also demonstrated diminished biofilm viability and epithelial adherence. However, coinfection with influenza virus ameliorated this colonization defect in vivo. Further, viral coinfection ultimately induced a similar magnitude of middle ear infection by both phase variants. These data indicate that despite inherent differences in colonization, the influenza A virus exacerbation of experimental middle ear infection is independent of the pneumococcal phase. These findings provide new insights into the synergistic link between pneumococcus and influenza virus in the context of otitis media. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  15. Stability of the gorilla microbiome despite simian immunodeficiency virus infection

    OpenAIRE

    Moeller, A. H.; Peeters, Martine; Ayouba, Ahidjo; Ngole, E. M.; Esteban, A.; Hahn, B. H.; Ochman, H.

    2015-01-01

    Simian immunodeficiency viruses (SIVs) have been discovered in over 45 primate species; however, the pathogenic potential of most SIV strains remains unknown due to difficulties inherent in observing wild populations. Because those SIV infections that are pathogenic have been shown to induce changes in the host's gut microbiome, monitoring the microbiota present in faecal samples can provide a noninvasive means for studying the effects of SIV infection on the health of wild-living primates. H...

  16. Transient Hearing Loss in Adults Associated With Zika Virus Infection.

    Science.gov (United States)

    Vinhaes, Eriko S; Santos, Luciane A; Dias, Lislane; Andrade, Nilvano A; Bezerra, Victor H; de Carvalho, Anderson T; de Moraes, Laise; Henriques, Daniele F; Azar, Sasha R; Vasilakis, Nikos; Ko, Albert I; Andrade, Bruno B; Siqueira, Isadora C; Khouri, Ricardo; Boaventura, Viviane S

    2017-03-01

    In 2015, during the outbreak of Zika virus (ZIKV) in Brazil, we identified 3 cases of acute hearing loss after exanthematous illness. Serology yielded finding compatible with ZIKV as the cause of a confirmed (n = 1) and a probable (n = 2) flavivirus infection, indicating an association between ZIKV infection and transient hearing loss. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America.

  17. Neopterin and human immunodeficiency virus infection

    DEFF Research Database (Denmark)

    Hofmann, B

    1993-01-01

    Neopterin concentrations increase in serum and urine within the first week of infection with HIV and remain increased throughout the infection. In particular, changes in neopterin concentration precede decreases in CD4 T cell numbers and the development of clinical disease, and they can be used t...

  18. The biology of human immunodeficiency virus infection.

    Science.gov (United States)

    Kotler, Donald P

    2004-08-01

    The aim of this article is to review the basic biology of infection with HIV-1 and the development of the acquired immunodeficiency syndrome. The discussion will include epidemiology, general description of the retroviruses, pathogenesis of the immune deficiency, clinical consequences, treatment, and treatment outcomes. Aspects of the infection that affect protein and energy balance will be identified.

  19. Outbreak of Zika virus infection in Singapore: an epidemiological, entomological, virological, and clinical analysis.

    Science.gov (United States)

    2017-08-01

    An outbreak of Zika virus infection was detected in Singapore in August, 2016. We report the first comprehensive analysis of a national response to an outbreak of Zika virus infection in Asia. In the first phase of the outbreak, patients with suspected Zika virus infection were isolated in two national referral hospitals until their serum tested negative for the virus. Enhanced vector control and community engagement measures were deployed in disease clusters, including stepped-up mosquito larvicide and adulticide use, community participation in source reduction (destruction of mosquito breeding sites), and work with the local media to promote awareness of the outbreak. Clinical and epidemiological data were collected from patients with confirmed Zika virus infection during the first phase. In the second phase, admission into hospitals for isolation was stopped but vector control efforts continued. Mosquitoes were captured from areas with Zika disease clusters to assess which species were present, their breeding numbers, and to test for Zika virus. Mosquito virus strains were compared with human strains through phylogenetic analysis after full genome sequencing. Reproductive numbers and inferred dates of strain diversification were estimated through Bayesian analyses. From Aug 27 to Nov 30, 2016, 455 cases of Zika virus infection were confirmed in Singapore. Of 163 patients with confirmed Zika virus infection who presented to national referral hospitals during the first phase of the outbreak, Zika virus was detected in the blood samples of 97 (60%) patients and the urine samples of 157 (96%) patients. There were 15 disease clusters, 12 of which had high Aedes aegypti breeding percentages. Captured mosquitoes were pooled into 517 pools for Zika virus screening; nine abdomen pools (2%) were positive for Zika virus, of which seven head and thorax pools were Zika-virus positive. In the phylogenetic analysis, all mosquito sequences clustered within the outbreak lineage

  20. Renal disease in cats infected with feline immunodeficiency virus.

    Science.gov (United States)

    Baxter, K J; Levy, J K; Edinboro, C H; Vaden, S L; Tompkins, M B

    2012-01-01

    Feline immunodeficiency virus (FIV) and human immunodeficiency virus (HIV) infection cause similar clinical syndromes of immune dysregulation, opportunistic infections, inflammatory diseases, and neoplasia. Renal disease is the 4th most common cause of death associated with HIV infection. To investigate the association between FIV infection and renal disease in cats. Client-owned cats (153 FIV-infected, 306 FIV-noninfected) and specific-pathogen-free (SPF) research colony cats (95 FIV-infected, 98 FIV-noninfected). A mixed retrospective/prospective cross-sectional study. Blood urea nitrogen (BUN), serum creatinine, urine specific gravity (USG), and urine protein:creatinine ratio (UPC) data were compared between FIV-infected and FIV-noninfected cats. In FIV-infected cats, total CD4+ and CD8+ T lymphocytes were measured using flow cytometry, and CD4+:CD8+ T lymphocyte ratio was calculated. Renal azotemia was defined as a serum creatinine ≥ 1.9 mg/dL with USG ≤ 1.035. Proteinuria was defined as a UPC > 0.4 with an inactive urine sediment. Among the client-owned cats, no association was detected between FIV infection and renal azotemia (P = .24); however, a greater proportion of FIV-infected cats were proteinuric (25.0%, 16 of 64 cats) compared to FIV-noninfected cats (10.3%, 20 of 195 cats) (P < .01). Neither neuter status nor health status were risk factors for proteinuria in FIV-infected cats, but UPC was positively correlated with the CD4+:CD8+ T lymphocyte ratio (Spearman's rho = 0.37, P = .01). Among the SPF research colony cats, no association was detected between FIV infection and renal azotemia (P = .21) or proteinuria (P = .25). Proteinuria but not azotemia was associated with natural FIV infection. Copyright © 2012 by the American College of Veterinary Internal Medicine.

  1. Neutralizing Antibodies and Pathogenesis of Hepatitis C Virus Infection

    Directory of Open Access Journals (Sweden)

    Françoise Stoll-Keller

    2012-10-01

    Full Text Available Hepatitis C virus (HCV infection is a major cause of chronic liver disease worldwide. The interplay between the virus and host innate and adaptive immune responses determines the outcome of infection. There is increasing evidence that host neutralizing responses play a relevant role in the resulting pathogenesis. Furthermore, viral evasion from host neutralizing antibodies has been revealed to be an important contributor in leading both to viral persistence in acute liver graft infection following liver transplantation, and to chronic viral infection. The development of novel model systems to study HCV entry and neutralization has allowed a detailed understanding of the molecular mechanisms of virus-host interactions during antibody-mediated neutralization. The understanding of these mechanisms will ultimately contribute to the development of novel antiviral preventive strategies for liver graft infection and an urgently needed vaccine. This review summarizes recent concepts of the role of neutralizing antibodies in viral clearance and protection, and highlights consequences of viral escape from neutralizing antibodies in the pathogenesis of HCV infection.

  2. Heterologous RNA-silencing suppressors from both plant- and animal-infecting viruses support plum pox virus infection.

    Science.gov (United States)

    Maliogka, Varvara I; Calvo, María; Carbonell, Alberto; García, Juan Antonio; Valli, Adrian

    2012-07-01

    HCPro, the RNA-silencing suppressor (RSS) of viruses belonging to the genus Potyvirus in the family Potyviridae, is a multifunctional protein presumably involved in all essential steps of the viral infection cycle. Recent studies have shown that plum pox potyvirus (PPV) HCPro can be replaced successfully by cucumber vein yellowing ipomovirus P1b, a sequence-unrelated RSS from a virus of the same family. In order to gain insight into the requirement of a particular RSS to establish a successful potyviral infection, we tested the ability of different heterologous RSSs from both plant- and animal-infecting viruses to substitute for HCPro. Making use of engineered PPV chimeras, we show that PPV HCPro can be replaced functionally by some, but not all, unrelated RSSs, including the NS1 protein of the mammal-infecting influenza A virus. Interestingly, the capacity of a particular RSS to replace HCPro does not correlate strictly with its RNA silencing-suppression strength. Altogether, our results suggest that not all suppression strategies are equally suitable for efficient escape of PPV from the RNA-silencing machinery. The approach followed here, based on using PPV chimeras in which an under-consideration RSS substitutes for HCPro, could further help to study the function of diverse RSSs in a 'highly sensitive' RNA-silencing context, such as that taking place in plant cells during the process of a viral infection.

  3. Spatial analysis of feline immunodeficiency virus infection in cougars.

    Science.gov (United States)

    Wheeler, David C; Waller, Lance A; Biek, Roman

    2010-07-01

    The cougar (Puma concolor) is a large predatory feline found widely in the Americas that is susceptible to feline immunodeficiency virus (FIV), a fast-evolving lentivirus found in wild feline species that is analogous to simian immunodeficiency viruses in wild primates and belongs to the same family of viruses as human immunodeficiency virus. FIV infection in cougars can lead to a weakened immune system that creates opportunities for other infecting agents. FIV prevalence and lineages have been studied previously in several areas in the western United States, but typically without spatially explicit statistical techniques. To describe the distribution of FIV in a sample of cougars located in the northern Rocky Mountain region of North America, we first used kernel density ratio estimation to map the log relative risk of FIV. The risk surface showed a significant cluster of FIV in northwestern Montana. We also used Bayesian cluster models for genetic data to investigate the spatial structure of the feline immunodeficiency virus with virus genetic sequence data. A result of the models was two spatially distinct FIV lineages that aligned considerably with an interstate highway in Montana. Our results suggest that the use of spatial information and models adds novel insight when investigating an infectious animal disease. The results also suggest that the influence of landscape features likely plays an important role in the spatiotemporal spread of an infectious disease within wildlife populations.

  4. Spinal cord toxoplasmosis in human immunodeficiency virus infection/acquired immunodeficiency syndrome.

    Science.gov (United States)

    García-García, Concepción; Castillo-Álvarez, Federico; Azcona-Gutiérrez, José M; Herraiz, María J; Ibarra, Valvanera; Oteo, José A

    2015-05-01

    Neurological complications in patients with human immunodeficiency virus infection/acquired immunodeficiency syndrome (HIV/AIDS) are still common, even in the era of highly active antiretroviral therapy. Opportunistic infections, immune reconstitution, the virus itself, antiretroviral drugs and neurocognitive disorders have to be considered when establishing the differential diagnosis. Toxoplasmic encephalitis remains the major cause of space-occupying lesions in the brain of patients with HIV/AIDS; however, spinal cord involvement has been reported infrequently. Here, we review spinal cord toxoplasmosis in HIV infection and illustrate the condition with a recent case from our hospital. We suggest that most patients with HIV/AIDS and myelitis with enhanced spine lesions, multiple brain lesions and positive serology for Toxoplasma gondii should receive immediate empirical treatment for toxoplasmosis, and a biopsy should be performed in those cases without clinical improvement or with deterioration.

  5. Alteration of cell cycle progression by Sindbis virus infection

    Energy Technology Data Exchange (ETDEWEB)

    Yi, Ruirong; Saito, Kengo [Department of Molecular Virology, Graduate School of Medicine, Chiba University Graduate School of Medicine, 1-8-1 Inohana, Chiba 260-8670 (Japan); Isegawa, Naohisa [Laboratory Animal Center, Graduate School of Medicine, Chiba University Graduate School of Medicine, 1-8-1 Inohana, Chiba 260-8670 (Japan); Shirasawa, Hiroshi, E-mail: sirasawa@faculty.chiba-u.jp [Department of Molecular Virology, Graduate School of Medicine, Chiba University Graduate School of Medicine, 1-8-1 Inohana, Chiba 260-8670 (Japan)

    2015-07-10

    We examined the impact of Sindbis virus (SINV) infection on cell cycle progression in a cancer cell line, HeLa, and a non-cancerous cell line, Vero. Cell cycle analyses showed that SINV infection is able to alter the cell cycle progression in both HeLa and Vero cells, but differently, especially during the early stage of infection. SINV infection affected the expression of several cell cycle regulators (CDK4, CDK6, cyclin E, p21, cyclin A and cyclin B) in HeLa cells and caused HeLa cells to accumulate in S phase during the early stage of infection. Monitoring SINV replication in HeLa and Vero cells expressing cell cycle indicators revealed that SINV which infected HeLa cells during G{sub 1} phase preferred to proliferate during S/G{sub 2} phase, and the average time interval for viral replication was significantly shorter in both HeLa and Vero cells infected during G{sub 1} phase than in cells infected during S/G{sub 2} phase. - Highlights: • SINV infection was able to alter the cell cycle progression of infected cancer cells. • SINV infection can affect the expression of cell cycle regulators. • SINV infection exhibited a preference for the timing of viral replication among the cell cycle phases.

  6. Alteration of cell cycle progression by Sindbis virus infection

    International Nuclear Information System (INIS)

    Yi, Ruirong; Saito, Kengo; Isegawa, Naohisa; Shirasawa, Hiroshi

    2015-01-01

    We examined the impact of Sindbis virus (SINV) infection on cell cycle progression in a cancer cell line, HeLa, and a non-cancerous cell line, Vero. Cell cycle analyses showed that SINV infection is able to alter the cell cycle progression in both HeLa and Vero cells, but differently, especially during the early stage of infection. SINV infection affected the expression of several cell cycle regulators (CDK4, CDK6, cyclin E, p21, cyclin A and cyclin B) in HeLa cells and caused HeLa cells to accumulate in S phase during the early stage of infection. Monitoring SINV replication in HeLa and Vero cells expressing cell cycle indicators revealed that SINV which infected HeLa cells during G 1 phase preferred to proliferate during S/G 2 phase, and the average time interval for viral replication was significantly shorter in both HeLa and Vero cells infected during G 1 phase than in cells infected during S/G 2 phase. - Highlights: • SINV infection was able to alter the cell cycle progression of infected cancer cells. • SINV infection can affect the expression of cell cycle regulators. • SINV infection exhibited a preference for the timing of viral replication among the cell cycle phases

  7. The role of neutrophils in the upper and lower respiratory tract during influenza virus infection of mice

    Directory of Open Access Journals (Sweden)

    Reading Patrick C

    2008-08-01

    Full Text Available Abstract Background Neutrophils have been shown to play a role in host defence against highly virulent and mouse-adapted strains of influenza virus, however it is not clear if an effective neutrophil response is an important factor moderating disease severity during infection with other virus strains. In this study, we have examined the role of neutrophils during infection of mice with influenza virus strain HKx31, a virus strain of the H3N2 subtype and of moderate virulence for mice, to determine the role of neutrophils in the early phase of infection and in clearance of influenza virus from the respiratory tract during the later phase of infection. Methods The anti-Gr-1 monoclonal antibody (mAb RB6-8C5 was used to (i identify neutrophils in the upper (nasal tissues and lower (lung respiratory tract of uninfected and influenza virus-infected mice, and (ii deplete neutrophils prior to and during influenza virus infection of mice. Results Neutrophils were rapidly recruited to the upper and lower airways following influenza virus infection. We demonstrated that use of mAb RB6-8C5 to deplete C57BL/6 (B6 mice of neutrophils is complicated by the ability of this mAb to bind directly to virus-specific CD8+ T cells. Thus, we investigated the role of neutrophils in both the early and later phases of infection using CD8+ T cell-deficient B6.TAP-/- mice. Infection of B6.TAP-/- mice with a low dose of influenza virus did not induce clinical disease in control animals, however RB6-8C5 treatment led to profound weight loss, severe clinical disease and enhanced virus replication throughout the respiratory tract. Conclusion Neutrophils play a critical role in limiting influenza virus replication during the early and later phases of infection. Furthermore, a virus strain of moderate virulence can induce severe clinical disease in the absence of an effective neutrophil response.

  8. Persistent infection with ebola virus under conditions of partial immunity.

    Science.gov (United States)

    Gupta, Manisha; Mahanty, Siddhartha; Greer, Patricia; Towner, Jonathan S; Shieh, Wun-Ju; Zaki, Sherif R; Ahmed, Rafi; Rollin, Pierre E

    2004-01-01

    Ebola hemorrhagic fever in humans is associated with high mortality; however, some infected hosts clear the virus and recover. The mechanisms by which this occurs and the correlates of protective immunity are not well defined. Using a mouse model, we determined the role of the immune system in clearance of and protection against Ebola virus. All CD8 T-cell-deficient mice succumbed to subcutaneous infection and had high viral antigen titers in tissues, whereas mice deficient in B cells or CD4 T cells cleared infection and survived, suggesting that CD8 T cells, independent of CD4 T cells and antibodies, are critical to protection against subcutaneous Ebola virus infection. B-cell-deficient mice that survived the primary subcutaneous infection (vaccinated mice) transiently depleted or not depleted of CD4 T cells also survived lethal intraperitoneal rechallenge for >/==" BORDER="0">25 days. However, all vaccinated B-cell-deficient mice depleted of CD8 T cells had high viral antigen titers in tissues following intraperitoneal rechallenge and died within 6 days, suggesting that memory CD8 T cells by themselves can protect mice from early death. Surprisingly, vaccinated B-cell-deficient mice, after initially clearing the infection, were found to have viral antigens in tissues later (day 120 to 150 post-intraperitoneal infection). Furthermore, following intraperitoneal rechallenge, vaccinated B-cell-deficient mice that were transiently depleted of CD4 T cells had high levels of viral antigen in tissues earlier (days 50 to 70) than vaccinated undepleted mice. This demonstrates that under certain immunodeficiency conditions, Ebola virus can persist and that loss of primed CD4 T cells accelerates the course of persistent infections. These data show that CD8 T cells play an important role in protection against acute disease, while both CD4 T cells and antibodies are required for long-term protection, and they provide evidence of persistent infection by Ebola virus suggesting

  9. Preventive and therapeutic challenges in combating Zika virus infection: are we getting any closer?

    Science.gov (United States)

    Singh, Meera V; Weber, Emily A; Singh, Vir B; Stirpe, Nicole E; Maggirwar, Sanjay B

    2017-06-01

    The neuroteratogenic nature of Zika Virus (ZIKV) infection has converted what would have been a tropical disease into a global threat. Zika is transmitted vertically via infected placental cells especially in the first and second trimesters. In the developing central nervous system (CNS), ZIKV can infect and induce apoptosis of neural progenitor cells subsequently causing microcephaly as well as other neuronal complications in infants. Its ability to infect multiple cell types (placental, dermal, and neural) and increased environmental stability as compared to other flaviviruses (FVs) has broadened the transmission routes for ZIKV infection from vector-mediated to transmitted via body fluids. To further complicate the matters, it is genetically similar (about 40%) with the four serotypes of dengue virus (DENV), so much so that it can almost be called a fifth DENV serotype. This homology poses the risk of causing cross-reactive immune responses and subsequent antibody-dependent enhancement (ADE) of infection in case of secondary infections or for immunized individuals. All of these factors complicate the development of a single preventive vaccine candidate or a pharmacological intervention that will completely eliminate or cure ZIKV infection. We discuss all of these factors in detail in this review and conclude that a combinatorial approach including immunization and treatment might prove to be the winning strategy.

  10. Zika Virus Infection and Microcephaly: Evidence for a Causal Link

    Directory of Open Access Journals (Sweden)

    Jin-Na Wang

    2016-10-01

    Full Text Available Zika virus (ZIKV is a flavivirus related to the Dengue, yellow fever and West Nile viruses. Since the explosive outbreaks of ZIKV in Latin America in 2015, a sudden increase in the number of microcephaly cases has been observed in infants of women who were pregnant when they contracted the virus. The severity of this condition raises grave concerns, and extensive studies on the possible link between ZIKV infection and microcephaly have been conducted. There is substantial evidence suggesting that there is a causal link between ZIKV and microcephaly, however, future studies are warranted to solidify this association. To summarize the most recent evidence on this issue and provide perspectives for future studies, we reviewed the literature to identify existing evidence of the causal link between ZIKV infection and microcephaly within research related to the epidemics, laboratory diagnosis, and possible mechanisms.

  11. Autoimmune Neurological Conditions Associated With Zika Virus Infection

    Directory of Open Access Journals (Sweden)

    Yeny Acosta-Ampudia

    2018-04-01

    Full Text Available Zika virus (ZIKV is an emerging flavivirus rapidly spreading throughout the tropical Americas. Aedes mosquitoes is the principal way of transmission of the virus to humans. ZIKV can be spread by transplacental, perinatal, and body fluids. ZIKV infection is often asymptomatic and those with symptoms present minor illness after 3 to 12 days of incubation, characterized by a mild and self-limiting disease with low-grade fever, conjunctivitis, widespread pruritic maculopapular rash, arthralgia and myalgia. ZIKV has been linked to a number of central and peripheral nervous system injuries such as Guillain-Barré syndrome (GBS, transverse myelitis (TM, meningoencephalitis, ophthalmological manifestations, and other neurological complications. Nevertheless, mechanisms of host-pathogen neuro-immune interactions remain incompletely elucidated. This review provides a critical discussion about the possible mechanisms underlying the development of autoimmune neurological conditions associated with Zika virus infection.

  12. Zika Virus Infection and Microcephaly: Evidence for a Causal Link.

    Science.gov (United States)

    Wang, Jin-Na; Ling, Feng

    2016-10-20

    Zika virus (ZIKV) is a flavivirus related to the Dengue, yellow fever and West Nile viruses. Since the explosive outbreaks of ZIKV in Latin America in 2015, a sudden increase in the number of microcephaly cases has been observed in infants of women who were pregnant when they contracted the virus. The severity of this condition raises grave concerns, and extensive studies on the possible link between ZIKV infection and microcephaly have been conducted. There is substantial evidence suggesting that there is a causal link between ZIKV and microcephaly, however, future studies are warranted to solidify this association. To summarize the most recent evidence on this issue and provide perspectives for future studies, we reviewed the literature to identify existing evidence of the causal link between ZIKV infection and microcephaly within research related to the epidemics, laboratory diagnosis, and possible mechanisms.

  13. Special Issue: Viruses Infecting Fish, Amphibians, and Reptiles

    Directory of Open Access Journals (Sweden)

    V. Gregory Chinchar

    2011-09-01

    Full Text Available Although viruses infecting and affecting humans are the focus of considerable research effort, viruses that target other animal species, including cold-blooded vertebrates, are receiving increased attention. In part this reflects the interests of comparative virologists, but increasingly it is based on the impact that many viruses have on ecologically and commercially important animals. Frogs and other amphibians are sentinels of environmental health and their disappearance following viral or fungal (chytrid infection is a cause for alarm. Likewise, because aquaculture and mariculture are providing an increasingly large percentage of the “seafood” consumed by humans, viral agents that adversely impact the harvest of cultured fish and amphibians are of equal concern. [...

  14. Haematology of infectious bursal disease virus infected chickens on ...

    African Journals Online (AJOL)

    Garlic (Allium sativum) is an herbal spice proven to posses antimicrobial and immunostimulating properties which could be useful in the control of endemic diseases of poultry such as infectious bursal disease (IBD). Its effect on IBD virus infection was therefore investigated via haematological assessment. One hundred and ...

  15. Hepatitis B Virus Infection In Patients With Homozygous Sickle Cell ...

    African Journals Online (AJOL)

    Nnebe-Agumadu U H, and Abiodun P O. Hepatitis B Virus Infection in Patients with Homozygous Sickle Cell Disease (HbSS): Need for Intervention. Annals Biomedical Sciences 2002; 1:79-87. This is a prospective study of 213 patients with sickle cell anaemia (SCA) (112 males and 101 females) aged 6 months to 18 years ...

  16. Hepatitis B virus infection among pregnant women delivering at ...

    African Journals Online (AJOL)

    Objective: To determine the prevalence of hepatitis B virus (HBV) carrier and infectivity status among women delivering at Harare Maternity Hospital. Design: A serological survey study of pregnant women admitted for labour and delivery. Setting: Harare Maternity Hospital, Harare, Zimbabwe between June 1996 and June ...

  17. Primary Epstein-Barr virus infection with neurological complications

    NARCIS (Netherlands)

    Bathoorn, E.; Vlaminckx, B.J.; Schoondermark-Stolk, S.; Donders, R.; Meulen, M. van der; Thijsen, S.F.

    2011-01-01

    Several case studies have reported on neurological complications caused by a primary Epstein-Barr virus (EBV) infection. We aimed to investigate the viral loads and the clinical and inflammatory characteristics of this disease entity. We evaluated all 84 cases in which the EBV polymerase chain

  18. Neutralizing antibodies in cats infected with feline immunodeficiency virus.

    NARCIS (Netherlands)

    F. Tozzini; D. Matteucci; P. Bandecchi; F. Baldinotti; C.H.J. Siebelink (Kees); A.D.M.E. Osterhaus (Albert); M. Bendinelli

    1993-01-01

    textabstractSera from cats experimentally infected with five isolates of feline immunodeficiency virus (FIV) from various geographical regions and from FIV enzyme-linked immunosorbent assay-seropositive field cats from four European countries neutralized the Petaluma strain of FIV (FIV-P),

  19. Vaccination against feline immunodeficiency virus using fixed infected cells

    NARCIS (Netherlands)

    Horzinek, M.C.; Verschoor, E.J.; Vliet, A.L.W. van; Egberink, H.F.; Hesselink, W.; Alphen, W.E. van; Joosten, I.; Boog, C.J.P.; Ronde, A. de

    1995-01-01

    Crandell feline kidney cells and feline thymocytes, either feline immunodeficiency virus (FIV) infected or uninfected, were fixed with paraformaldehyde and used to vaccinate cats. The cells were mixed with a 30:70 water/mineral oil emulsion containing 250 mu g ml−1 N-acetyl-d-glucosaminyl-beta-(1

  20. Evaluation of subunit vaccines against feline immunodeficiency virus infection

    NARCIS (Netherlands)

    Horzinek, M.C.; Verschoor, E.J.; Willemse, M.J.; Stam, J.G.; Vliet, A.L.W. van; Pouwels, H.; Chalmers, S.K.; Sondermeijer, P.J.; Hesselink, W.; Ronde, A. de

    1996-01-01

    Subunit vaccines prepared against feline immunodeficiency virus (FIV) infection were evaluated in two trials. First, cats were immunized with bacterial expression products of an envelope fragment that contained the V3 neutralization domain of the FIV surface protein fused to either galactokinase

  1. Role of antibodies in controlling dengue virus infection

    NARCIS (Netherlands)

    van der Schaar, Hilde M.; Wilschut, Jan C.; Smit, Jolanda M.

    The incidence and disease burden of arthropod-borne flavivirus infections have dramatically increased during the last decades due to major societal and economic changes, including massive urbanization, lack of vector control, travel, and international trade. Specifically, in the case of dengue virus

  2. Transgenic tomato hybrids resistant to tomato spotted wilt virus infection.

    NARCIS (Netherlands)

    Haan, de P.; Ultzen, T.; Prins, M.; Gielen, J.; Goldbach, R.; Grinsven, van M.

    1996-01-01

    Tomato spotted wilt virus (TSWV) infections cause significant economic losses in the commercial culture of tomato (Lycopersicon esculentum). Culture practices have only been marginally effective in controlling TSWV. The ultimate way to minimize losses caused by TSWV is resistant varieties. These can

  3. Infection of hepatitis C virus genotypes in hepatocellular carcinoma ...

    African Journals Online (AJOL)

    The aim of this retrospective study was to investigate the infection of hepatitis C virus (HCV) genotypes in hepatocellular carcinoma (HCC) patients from rural areas of Faisalabad region. Among 179 HCC subjects, men and women were 51 and 49%, respectively. All samples positive for HCV RNA by qualitative PCR were ...

  4. Primary Epstein-Barr virus infection with neurological complications

    NARCIS (Netherlands)

    Bathoorn, Erik; Vlaminckx, Bart J. M.; Schoondermark-Stolk, Sung; Donders, Richard; Van Der Meulen, Marjon; Thijsen, Steven F. T.

    Several case studies have reported on neurological complications caused by a primary Epstein-Barr virus (EBV) infection. We aimed to investigate the viral loads and the clinical and inflammatory characteristics of this disease entity. We evaluated all 84 cases in which the EBV polymerase chain

  5. Transfusion Related Hepatitis C Virus (HCV) Infection in Sickle Cell ...

    African Journals Online (AJOL)

    Rev Olaleye

    ABSTRACT: This study aimed to determine retrospectively, the prevalence of hepatitis C virus infection in relation to a background history of blood transfusion; through anti HCV antibody screening test, amongst adult sickle cell disease patients. Anti HCV antibody was tested for in the serum of 92 consecutively selected ...

  6. Chronic West Nile virus infection in kea (Nestor notabilis)

    Czech Academy of Sciences Publication Activity Database

    Bakonyi, T.; Gaydon, G. K.; Schwing, R.; Vogl, W.; Häbich, A.-C.; Thaller, D.; Weissenböck, H.; Rudolf, Ivo; Hubálek, Zdeněk; Nowotny, N.

    2016-01-01

    Roč. 183, February (2016), s. 135-139 ISSN 0378-1135 EU Projects: European Commission(XE) 261504 - EDENEXT; European Commission(XE) 261391 - EUROWESTNILE Institutional support: RVO:68081766 Keywords : West Nile virus * Lineage 2 * Kea * Nestor notabilis * Psittaciformes * Persistent infection * Austria Subject RIV: FN - Epidemiology, Contagious Diseases ; Clinical Immunology Impact factor: 2.628, year: 2016

  7. Neurologic manifestations of human immunodeficiency virus infection in children

    NARCIS (Netherlands)

    Epstein, L. G.; Sharer, L. R.; Oleske, J. M.; Connor, E. M.; Goudsmit, J.; Bagdon, L.; Robert-Guroff, M.; Koenigsberger, M. R.

    1986-01-01

    This report describes the neurologic manifestations of 36 children with human immunodeficiency virus (HIV) infection. In this cohort, in 16 of 21 children with acquired immunodeficiency syndrome (AIDS), three of 12 children with AIDS-related complex, and one of three asymptomatic seropositive

  8. Prevalence And Risk Factors For Human Pappiloma Virus Infection ...

    African Journals Online (AJOL)

    Human Pappiloma Virus (HPV) infection is a disease of global public health importance, culminating into a high risk of cervical cancer. Most of the risk factors are modifiable, thus making HPV itself preventable. Efforts towards community HPV prevention and vaccination have not yielded the desired results, most especially ...

  9. Zika virus infection: The resurgence of a neglected disease

    Directory of Open Access Journals (Sweden)

    Tushar Kambale

    2016-01-01

    Full Text Available "Zika virus" (ZIKV is an enveloped, icosahedral virus and has a positive-sense, single-stranded RNA genome approximately 11 kb in length. Genetic studies have revealed three ZIKV lineages: East African, West African, and Asian. Serologic studies and virus isolations have demonstrated that the virus has a wide geographic distribution, spanning East and West Africa, the Americas, Indian subcontinent, and Southeast Asia. ZIKV can cause complications such as Guillain-Barré syndrome, meningitis, meningoencephalitis, and myelitis. During pregnancy ZIKV infection can lead to miscarriages and microcephaly, cerebral calcifications, macular neuroretinal atrophy, and loss of foveal reflex in the fetus. A clinically suspected case of infection with dengue negative result should be further tested for Flavivirus, including Zika. Immunofluorescence or enzyme-linked immunosorbent assay is used to detect specific IgM or IgG antibodies against ZIKV. In cases of positive ZIKV infection, symptomatic treatment should be given after excluding other condition such as dengue, malaria, and bacterial infections.

  10. Health Disparity in Human Papilloma Virus Related Infections | Poku ...

    African Journals Online (AJOL)

    In spite of the volume of information of Human Papilloma Virus (HPV) and the HPV vaccines, there are racial and gender differences in the knowledge and awareness of HPV among Guyanese. The study aimed to assess the knowledge and attitude towards HPV infection, cervical cancer and HPV vaccines. The study was ...

  11. Progression of experimental chronic Aleutian mink disease virus infection

    DEFF Research Database (Denmark)

    Jensen, Trine Hammer; Chriél, Mariann; Hansen, Mette Sif

    2016-01-01

    Aleutian mink disease virus (AMDV) is found world-wide and has a major impact on mink health and welfare by decreasing reproduction and fur quality. In the majority of mink, the infection is subclinical and the diagnosis must be confirmed by serology or polymerase chain reaction (PCR). Increased ...

  12. Hepatitus B virus infection : factors influencing the outcome

    NARCIS (Netherlands)

    J. van Hattum (Jan)

    1986-01-01

    textabstractThis study was designed to find correlations between the various courses of disease after hepatitis B virus (HBV) infection and factors that could conceivably have influenced the course of disease. The aim of the study was to find correlations between parameters of viral replication and

  13. Viral Infections in Pregnancy: A Focus on Ebola Virus.

    Science.gov (United States)

    Olgun, Nicole S

    2018-01-30

    During gestation, the immune response of the placenta to viruses and other pathogens plays an important role in determining a pregnant woman's vulnerability toward infectious diseases. Located at the maternal- fetal interface, trophoblast cells serve to minimize the spread of viruses between the host and developing fetus through an intricate system of innate antiviral immune signaling. Adverse pregnancy outcomes, ranging from learning disabilities to preterm birth and fetal death, are all documented results of a viral breach in the placental barrier. Viral infections during pregnancy can also be spread through blood and vaginal secretions, and during the post-natal period, via breast milk. Thus, even in the absence of vertical transmission of viral infection to the fetus, maternal health can still be compromised and threaten the pregnancy. The most common viral DNA isolates found in gestation are adenovirus, cytomegalovirus, and enterovirus. However, with the recent pandemic of Ebola virus, and the first documented case of a neonate to survive due to experimental therapies in 2017, it is becoming increasingly apparent that the changing roles and impacts of viral infection during pregnancy needs to be better understood, while strategies to minimize adverse pregnancy outcomes need to be identified. This review focuses on the adverse impacts of viral infection during gestation, with an emphasis on Ebola virus. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  14. Certain growth related attributes of bunchy top virus infected banana ...

    African Journals Online (AJOL)

    Effect of banana bunchy top virus (BBTV) on morpho-physiological characteristics of banana (Musa sp.) cv., Basrai plants was assessed. Healthy and BBTV infected samples of banana were collected from its open fields and micro-propagated aseptically. These plantlets were established in wire-house for three months.

  15. White Spot Syndrome Virus infection in Penaeus monodon is ...

    Indian Academy of Sciences (India)

    White Spot Syndrome Virus (WSSV) is a major pathogen in shrimp aquaculture, and its rampant spread has resulted in great economic loss. Identification of host cellular proteins interacting with WSSV will help in unravelling the repertoire of host proteins involved in WSSV infection. In this study, we have employed ...

  16. Reproduction and fertility in human immunodeficiency virus type-1 infection

    NARCIS (Netherlands)

    van Leeuwen, E.; Prins, J. M.; Jurriaans, S.; Boer, K.; Reiss, P.; Repping, S.; van der Veen, F.

    2007-01-01

    Human immunodeficiency virus type-1 (HIV-1) affects mostly men and women in their reproductive years. For those who have access to highly active antiretroviral therapy (HAART), the course of HIV-1 infection has shifted from a lethal to a chronic disease. As a result of this, many patients with HIV-1

  17. Awareness of Human Immunodeficiency Virus (HIV) infection among ...

    African Journals Online (AJOL)

    Objective: To determine the level of awareness of Human Immunodeficiency Virus (HIV) infection among antenatal clients in Nnewi Nigeria. Subjects and Methods: A cross sectional descriptive study of six hundred consecutive antenatal clients attending the Nnamdi Azikiwe University Teaching Hospital and five private ...

  18. Human Immunodeficiency Virus Infection in a rural community of ...

    African Journals Online (AJOL)

    Human Immunodeficiency Virus Infection in a rural community of Plateau State: effective control measures still a nightmare? GTA Jombo, DZ Egah, EB Banwat. Abstract. No Abstract. Nigerian Journal of Medicine Vol. 15(1) 2006: 49-52. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD ...

  19. Management of human immunodeficiency virus (HIV) infection in ...

    African Journals Online (AJOL)

    Management of human immunodeficiency virus (HIV) infection in adults in resource-limited countries: Challenges and prospects in Nigeria. AG Habib. Abstract. No Abstract. Annals of Ibadan Postgraduate Medicine Vol. 3 (1) 2005: pp. 26-32. Full Text: EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT · DOWNLOAD FULL ...

  20. Lethal Nipah virus infection induces rapid overexpression of CXCL10.

    Directory of Open Access Journals (Sweden)

    Cyrille Mathieu

    Full Text Available Nipah virus (NiV is a recently emerged zoonotic Paramyxovirus that causes regular outbreaks in East Asia with mortality rate exceeding 75%. Major cellular targets of NiV infection are endothelial cells and neurons. To better understand virus-host interaction, we analyzed the transcriptome profile of NiV infection in primary human umbilical vein endothelial cells. We further assessed some of the obtained results by in vitro and in vivo methods in a hamster model and in brain samples from NiV-infected patients. We found that NiV infection strongly induces genes involved in interferon response in endothelial cells. Among the top ten upregulated genes, we identified the chemokine CXCL10 (interferon-induced protein 10, IP-10, an important chemoattractant involved in the generation of inflammatory immune response and neurotoxicity. In NiV-infected hamsters, which develop pathology similar to what is seen in humans, expression of CXCL10 mRNA was induced in different organs with kinetics that followed NiV replication. Finally, we showed intense staining for CXCL10 in the brain of patients who succumbed to lethal NiV infection during the outbreak in Malaysia, confirming induction of this chemokine in fatal human infections. This study sheds new light on NiV pathogenesis, indicating the role of CXCL10 during the course of infection and suggests that this chemokine may serve as a potential new marker for lethal NiV encephalitis.

  1. Hepatitis B virus treatment in HIV-infected patients.

    Science.gov (United States)

    Thio, Chloe L

    Hepatitis B virus (HBV) infection is common in HIV-infected persons and is associated with increased risk of liver-related morbidity and mortality. Agents available to treat HBV infection in coinfected patients include lamivudine, entecavir, emtricitabine, adefovir, peginterferon alfa, and the recently approved telbivudine. Treatment decisions should take into account a number of factors, including antiretroviral therapy status, HBV genotype, prior experience of lamivudine, and the need to avoid drug resistance in both HIV- and HBV-infected persons. This article summarizes a presentation on treatment and management of HBV infection in HIV-infected patients made by Chloe L. Thio, MD, at the 9th Annual Ryan White CARE Act Update in Washington, DC. The original presentation is available as a Webcast at www.iasusa.org.

  2. Differential sensitivity of bat cells to infection by enveloped RNA viruses: coronaviruses, paramyxoviruses, filoviruses, and influenza viruses.

    Directory of Open Access Journals (Sweden)

    Markus Hoffmann

    Full Text Available Bats (Chiroptera host major human pathogenic viruses including corona-, paramyxo, rhabdo- and filoviruses. We analyzed six different cell lines from either Yinpterochiroptera (including African flying foxes and a rhinolophid bat or Yangochiroptera (genera Carollia and Tadarida for susceptibility to infection by different enveloped RNA viruses. None of the cells were sensitive to infection by transmissible gastroenteritis virus (TGEV, a porcine coronavirus, or to infection mediated by the Spike (S protein of SARS-coronavirus (SARS-CoV incorporated into pseudotypes based on vesicular stomatitis virus (VSV. The resistance to infection was overcome if cells were transfected to express the respective cellular receptor, porcine aminopeptidase N for TGEV or angiotensin-converting enzyme 2 for SARS-CoV. VSV pseudotypes containing the S proteins of two bat SARS-related CoV (Bg08 and Rp3 were unable to infect any of the six tested bat cell lines. By contrast, viral pseudotypes containing the surface protein GP of Marburg virus from the family Filoviridae infected all six cell lines though at different efficiency. Notably, all cells were sensitive to infection by two paramyxoviruses (Sendai virus and bovine respiratory syncytial virus and three influenza viruses from different subtypes. These results indicate that bat cells are more resistant to infection by coronaviruses than to infection by paramyxoviruses, filoviruses and influenza viruses. Furthermore, these results show a receptor-dependent restriction of the infection of bat cells by CoV. The implications for the isolation of coronaviruses from bats are discussed.

  3. Human Ebola virus infection results in substantial immune activation.

    Science.gov (United States)

    McElroy, Anita K; Akondy, Rama S; Davis, Carl W; Ellebedy, Ali H; Mehta, Aneesh K; Kraft, Colleen S; Lyon, G Marshall; Ribner, Bruce S; Varkey, Jay; Sidney, John; Sette, Alessandro; Campbell, Shelley; Ströher, Ute; Damon, Inger; Nichol, Stuart T; Spiropoulou, Christina F; Ahmed, Rafi

    2015-04-14

    Four Ebola patients received care at Emory University Hospital, presenting a unique opportunity to examine the cellular immune responses during acute Ebola virus infection. We found striking activation of both B and T cells in all four patients. Plasmablast frequencies were 10-50% of B cells, compared with less than 1% in healthy individuals. Many of these proliferating plasmablasts were IgG-positive, and this finding coincided with the presence of Ebola virus-specific IgG in the serum. Activated CD4 T cells ranged from 5 to 30%, compared with 1-2% in healthy controls. The most pronounced responses were seen in CD8 T cells, with over 50% of the CD8 T cells expressing markers of activation and proliferation. Taken together, these results suggest that all four patients developed robust immune responses during the acute phase of Ebola virus infection, a finding that would not have been predicted based on our current assumptions about the highly immunosuppressive nature of Ebola virus. Also, quite surprisingly, we found sustained immune activation after the virus was cleared from the plasma, observed most strikingly in the persistence of activated CD8 T cells, even 1 mo after the patients' discharge from the hospital. These results suggest continued antigen stimulation after resolution of the disease. From these convalescent time points, we identified CD4 and CD8 T-cell responses to several Ebola virus proteins, most notably the viral nucleoprotein. Knowledge of the viral proteins targeted by T cells during natural infection should be useful in designing vaccines against Ebola virus.

  4. Viral Infection of the Central Nervous System and Neuroinflammation Precede Blood-Brain Barrier Disruption during Japanese Encephalitis Virus Infection.

    Science.gov (United States)

    Li, Fang; Wang, Yueyun; Yu, Lan; Cao, Shengbo; Wang, Ke; Yuan, Jiaolong; Wang, Chong; Wang, Kunlun; Cui, Min; Fu, Zhen F

    2015-05-01

    Japanese encephalitis is an acute zoonotic, mosquito-borne disease caused by Japanese encephalitis virus (JEV). Japanese encephalitis is characterized by extensive inflammation in the central nervous system (CNS) and disruption of the blood-brain barrier (BBB). However, the pathogenic mechanisms contributing to the BBB disruption are not known. Here, using a mouse model of intravenous JEV infection, we show that virus titers increased exponentially in the brain from 2 to 5 days postinfection. This was accompanied by an early, dramatic increase in the level of inflammatory cytokines and chemokines in the brain. Enhancement of BBB permeability, however, was not observed until day 4, suggesting that viral entry and the onset of inflammation in the CNS occurred prior to BBB damage. In vitro studies revealed that direct infection with JEV could not induce changes in the permeability of brain microvascular endothelial cell monolayers. However, brain extracts derived from symptomatic JEV-infected mice, but not from mock-infected mice, induced significant permeability of the endothelial monolayer. Consistent with a role for inflammatory mediators in BBB disruption, the administration of gamma interferon-neutralizing antibody ameliorated the enhancement of BBB permeability in JEV-infected mice. Taken together, our data suggest that JEV enters the CNS, propagates in neurons, and induces the production of inflammatory cytokines and chemokines, which result in the disruption of the BBB. Japanese encephalitis (JE) is the leading cause of viral encephalitis in Asia, resulting in 70,000 cases each year, in which approximately 20 to 30% of cases are fatal, and a high proportion of patients survive with serious neurological and psychiatric sequelae. Pathologically, JEV infection causes an acute encephalopathy accompanied by BBB dysfunction; however, the mechanism is not clear. Thus, understanding the mechanisms of BBB disruption in JEV infection is important. Our data demonstrate

  5. Influenza D Virus Infection in Feral Swine Populations, United States.

    Science.gov (United States)

    Ferguson, Lucas; Luo, Kaijian; Olivier, Alicia K; Cunningham, Fred L; Blackmon, Sherry; Hanson-Dorr, Katie; Sun, Hailiang; Baroch, John; Lutman, Mark W; Quade, Bianca; Epperson, William; Webby, Richard; DeLiberto, Thomas J; Wan, Xiu-Feng

    2018-06-01

    Influenza D virus (IDV) has been identified in domestic cattle, swine, camelid, and small ruminant populations across North America, Europe, Asia, South America, and Africa. Our study investigated seroprevalence and transmissibility of IDV in feral swine. During 2012-2013, we evaluated feral swine populations in 4 US states; of 256 swine tested, 57 (19.1%) were IDV seropositive. Among 96 archived influenza A virus-seropositive feral swine samples collected from 16 US states during 2010-2013, 41 (42.7%) were IDV seropositive. Infection studies demonstrated that IDV-inoculated feral swine shed virus 3-5 days postinoculation and seroconverted at 21 days postinoculation; 50% of in-contact naive feral swine shed virus, seroconverted, or both. Immunohistochemical staining showed viral antigen within epithelial cells of the respiratory tract, including trachea, soft palate, and lungs. Our findings suggest that feral swine might serve an important role in the ecology of IDV.

  6. Influenza A virus infections in marine mammals and terrestrial carnivores.

    Science.gov (United States)

    Harder, Timm C; Siebert, Ursula; Wohlsein, Peter; Vahlenkamp, Thomas

    2013-01-01

    Influenza A viruses (IAV), members of the Orthomyxoviridae, cover a wide host spectrum comprising a plethora of avian and, in comparison, a few mammalian species. The viral reservoir and gene pool are kept in metapopulations of aquatic wild birds. The mammalian-adapted IAVs originally arose by transspecies transmission from avian sources. In swine, horse and man, species-adapted IAV lineages circulate independently of the avian reservoir and cause predominantly respiratory disease of highly variable severity. Sporadic outbreaks of IAV infections associated with pneumonic clinical signs have repeatedly occurred in marine mammals (harbour seals [Phoca vitulina]) off the New England coast of the U.S.A. due to episodic transmission of avian IAV. However, no indigenous marine mammal IAV lineages are described. In contrast to marine mammals, avian- and equine-derived IAVs have formed stable circulating lineages in terrestrial carnivores: IAVs of subtype H3N2 and H3N8 are found in canine populations in South Korea, China, and the U.S.A. Experimental infections revealed that dogs and cats can be infected with an even wider range of avian IAVs. Cats, in particular, also proved susceptible to native infection with human pandemic H1N1 viruses and, according to serological data, may be vulnerable to infection with further human-adapted IAVs. Ferrets are susceptible to a variety of avian and mammalian IAVs and are an established animal model of human IAV infection. Thus, a potential role of pet cats, dogs and ferrets as mediators of avian-derived viruses to the human population does exist. A closer observation for influenza virus infections and transmissions at this animal-human interface is indicated.

  7. Malignant syphilis with human immunodeficiency virus infection

    Directory of Open Access Journals (Sweden)

    Jiby Rajan

    2011-01-01

    Full Text Available Malignant syphilis or Lues maligna, commonly reported in the pre-antibiotic era, has now seen a resurgence with the advent of human immunodeficiency virus (HIV. Immunosuppression and sexual promiscuity set the stage for this deadly association of HIV and Treponema pallidum that can manifest atypically and can prove to cause diagnostic problems. We report one such case in a 30-year-old female who responded favorably to treatment with penicillin.

  8. Natural co-infection of Solanum tuberosum crops by the Potato yellow vein virus and potyvirus in Colombia

    Directory of Open Access Journals (Sweden)

    Angela Villamil-Garzón

    2014-08-01

    Full Text Available The Potato yellow vein virus (PYVV, a Crinivirus with an RNA tripartite genome, is the causal agent of the potato yellow vein disease, reported in Colombian since 1950, with yield reductions of up to 50%. Co-infection of two or more viruses is common in nature and can be associated with differences in virus accumulation and symptom expression. No evidence of mixed infection between PYVV and other viruses has been reported. In this study, eight plants showing yellowing PYVV symptoms: four Solanum tuberosum Group Phureja (P and four Group Andigena (A, were collected in Cundinamarca, Colombia to detect mixed infection in the isolates using next generation sequencing (NGS. The Potato virus Y (PVY complete genome (similar to N strain and the Potato virus V (PVV partial genomes were detected using NGS and re-confirmed by RT-PCR. Preliminary field screening in a large sample showed that PYVV and PVY co-infect potato plants with a prevalence of 21% within the P group and 23% within the A group. This is the first report of co-infection of PYVV and potyvirus in Colombia and with the use of NGS. Considering that potyviruses enhance symptom severity and/or yield reductions in mixed infections, our results may be relevant for disease diagnosis, breeding programs and tuber certification.

  9. Prior Puma Lentivirus Infection Modifies Early Immune Responses and Attenuates Feline Immunodeficiency Virus Infection in Cats

    Directory of Open Access Journals (Sweden)

    Wendy S. Sprague

    2018-04-01

    Full Text Available We previously showed that cats that were infected with non-pathogenic Puma lentivirus (PLV and then infected with pathogenic feline immunodeficiency virus (FIV (co-infection with the host adapted/pathogenic virus had delayed FIV proviral and RNA viral loads in blood, with viral set-points that were lower than cats infected solely with FIV. This difference was associated with global CD4+ T cell preservation, greater interferon gamma (IFN-γ mRNA expression, and no cytotoxic T lymphocyte responses in co-infected cats relative to cats with a single FIV infection. In this study, we reinforced previous observations that prior exposure to an apathogenic lentivirus infection can diminish the effects of acute infection with a second, more virulent, viral exposure. In addition, we investigated whether the viral load differences that were observed between PLV/FIV and FIV infected cats were associated with different immunocyte phenotypes and cytokines. We found that the immune landscape at the time of FIV infection influences the infection outcome. The novel findings in this study advance our knowledge about early immune correlates and documents an immune state that is associated with PLV/FIV co-infection that has positive outcomes for lentiviral diseases.

  10. Japanese encephalitis virus infection, diagnosis and control in domestic animals.

    Science.gov (United States)

    Mansfield, Karen L; Hernández-Triana, Luis M; Banyard, Ashley C; Fooks, Anthony R; Johnson, Nicholas

    2017-03-01

    Japanese encephalitis virus (JEV) is a significant cause of neurological disease in humans throughout Asia causing an estimated 70,000 human cases each year with approximately 10,000 fatalities. The virus contains a positive sense RNA genome within a host-derived membrane and is classified within the family Flaviviridae. Like many flaviviruses, it is transmitted by mosquitoes, particularly those of the genus Culex in a natural cycle involving birds and some livestock species. Spill-over into domestic animals results in a spectrum of disease ranging from asymptomatic infection in some species to acute neurological signs in others. The impact of JEV infection is particularly apparent in pigs. Although infection in adult swine does not result in symptomatic disease, it is considered a significant reproductive problem causing abortion, still-birth and birth defects. Infected piglets can display fatal neurological disease. Equines are also infected, resulting in non-specific signs including pyrexia, but occasionally leading to overt neurological disease that in extreme cases can lead to death. Veterinary vaccination is available for both pigs and horses. This review of JEV disease in livestock considers the current diagnostic techniques available for detection of the virus. Options for disease control and prevention within the veterinary sector are discussed. Such measures are critical in breaking the link to zoonotic transmission into the human population where humans are dead-end hosts. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

  11. First case of imported Zika virus infection in Spain.

    Science.gov (United States)

    Bachiller-Luque, Pablo; Domínguez-Gil González, Marta; Álvarez-Manzanares, Jesús; Vázquez, Ana; De Ory, Fernando; Sánchez-Seco Fariñas, M Paz

    2016-04-01

    We report a case of Zika virus (ZIKV) infection in a patient with diarrhea, fever, synovitis, non-purulent conjunctivitis, and with discreet retro-orbital pain, after returning from Colombia in January 2016. The patient referred several mosquito bites. Presence of ZIKV was detected by PCR (polymerase chain reaction) in plasma. Rapid microbiological diagnosis of ZIKV infection is needed in European countries with circulation of its vector, in order to avoid autochthonous circulation. The recent association of ZIKV infection with abortion and microcephaly, and a Guillain-Barré syndrome highlights the need for laboratory differentiation of ZIKV from other virus infection. Women with potential risk for Zika virus infection who are pregnant or planning to become pregnant must mention that fact during prenatal visits in order to be evaluated and properly monitored. Copyright © 2016 Elsevier España, S.L.U. y Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

  12. Group 2 innate lymphoid cell production of IL-5 is regulated by NKT cells during influenza virus infection.

    Directory of Open Access Journals (Sweden)

    Stacey Ann Gorski

    2013-09-01

    Full Text Available Respiratory virus infections, such as influenza, typically induce a robust type I (pro-inflammatory cytokine immune response, however, the production of type 2 cytokines has been observed. Type 2 cytokine production during respiratory virus infection is linked to asthma exacerbation; however, type 2 cytokines may also be tissue protective. Interleukin (IL-5 is a prototypical type 2 cytokine that is essential for eosinophil maturation and egress out of the bone marrow. However, little is known about the cellular source and underlying cellular and molecular basis for the regulation of IL-5 production during respiratory virus infection. Using a mouse model of influenza virus infection, we found a robust transient release of IL-5 into infected airways along with a significant and progressive accumulation of eosinophils into the lungs, particularly during the recovery phase of infection, i.e. following virus clearance. The cellular source of the IL-5 was group 2 innate lymphoid cells (ILC2 infiltrating the infected lungs. Interestingly, the progressive accumulation of eosinophils following virus clearance is reflected in the rapid expansion of c-kit⁺ IL-5 producing ILC2. We further demonstrate that the enhanced capacity for IL-5 production by ILC2 during recovery is concomitant with the enhanced expression of the IL-33 receptor subunit, ST2, by ILC2. Lastly, we show that NKT cells, as well as alveolar macrophages (AM, are endogenous sources of IL-33 that enhance IL-5 production from ILC2. Collectively, these results reveal that c-kit⁺ ILC2 interaction with IL-33 producing NKT and AM leads to abundant production of IL-5 by ILC2 and accounts for the accumulation of eosinophils observed during the recovery phase of influenza infection.

  13. Endogenous retroviruses mobilized during friend murine leukemia virus infection.

    Science.gov (United States)

    Boi, Stefano; Rosenke, Kyle; Hansen, Ethan; Hendrick, Duncan; Malik, Frank; Evans, Leonard H

    2016-12-01

    We have demonstrated in a mouse model that infection with a retrovirus can lead not only to the generation of recombinants between exogenous and endogenous gammaretrovirus, but also to the mobilization of endogenous proviruses by pseudotyping entire polytropic proviral transcripts and facilitating their infectious spread to new cells. However, the frequency of this occurrence, the kinetics, and the identity of mobilized endogenous proviruses was unclear. Here we find that these mobilized transcripts are detected after only one day of infection. They predominate over recombinant polytropic viruses early in infection, persist throughout the course of disease and are comprised of multiple different polytropic proviruses. Other endogenous retroviral elements such as intracisternal A particles (IAPs) were not detected. The integration of the endogenous transcripts into new cells could result in loss of transcriptional control and elevated expression which may facilitate pathogenesis, perhaps by contributing to the generation of polytropic recombinant viruses. Published by Elsevier Inc.

  14. Animal Models of Zika Virus Infection, Pathogenesis, and Immunity.

    Science.gov (United States)

    Morrison, Thomas E; Diamond, Michael S

    2017-04-15

    Zika virus (ZIKV) is an emerging mosquito-transmitted flavivirus that now causes epidemics affecting millions of people on multiple continents. The virus has received global attention because of some of its unusual epidemiological and clinical features, including persistent infection in the male reproductive tract and sexual transmission, an ability to cross the placenta during pregnancy and infect the developing fetus to cause congenital malformations, and its association with Guillain-Barré syndrome in adults. This past year has witnessed an intensive effort by the global scientific community to understand the biology of ZIKV and to develop pathogenesis models for the rapid testing of possible countermeasures. Here, we review the recent advances in and utility and limitations of newly developed mouse and nonhuman primate models of ZIKV infection and pathogenesis. Copyright © 2017 American Society for Microbiology.

  15. A systematic review of hepatitis E virus infection in children.

    Science.gov (United States)

    Verghese, Valsan Philip; Robinson, Joan L

    2014-09-01

    A systematic review was conducted, seeking all literature relevant to the epidemiology, clinical and laboratory features, and outcome of hepatitis E virus (HEV) infection in children. Transmission is thought to be primarily from fecal-oral transmission, with the role of transmission from animal reservoirs not being clear in children. Worldwide, seroprevalence is hepatitis A virus (HAV) infection, with most cases being subclinical. However, HEV differs from HAV in that infectivity is lower, perinatal transmission can result in neonatal morbidity and even mortality, and a chronic carrier state exists, accounting for chronic hepatitis in some pediatric solid organ transplant recipients. © The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  16. THE MOLECULAR EVOLUTION OF THE MOST DANGEROUS EMERGING VIRUS INFECTIONS

    Directory of Open Access Journals (Sweden)

    Popov NN

    2016-03-01

    barriers and infect new hosts. Really, many recently emerged human diseases are caused by viruses that display active recombination or reassortment. The continual shuffling of genes of influenza A represents a example of the key role of reassortment for the new virus emergence. Available data demonstrate the possible origin of SARS-CoV from recombination of different bat SL-CoVs viruses strains. However in other cases the emergence of a specific virus cannot be directly attributed to its ability to recombine. For example, although SIV recombines at a high rate in natural reservoirs, there is no evidence that recombination assisted the cross-species transfer of the virus from the chimpanzee into humans. But mutagenesis and recombination actively shape the further molecular history of HIV in humans. Also it is not proved that recombination precede the cross-species jump of the Ebola virus. In summary, the available data suggest that although recombination, reassortment and mutagenesis is sometimes directly involved to the process of cross-species transmission, it is not a necessary precursor to successful viral emergence. Further investigations are required to reveal the role of genetic change in the history of virus emergence. We believe that comprehensive description of molecular evolution of new viruses has led to a better understanding of the causes and predictability of infection emergence.

  17. Immune responses of ducks infected with duck Tembusu virus

    Directory of Open Access Journals (Sweden)

    Ning eLi

    2015-05-01

    Full Text Available Duck Tembusu virus (DTMUV can cause serious disease in ducks, characterized by reduced egg production. Although the virus has been isolated and detection methods developed, the host immune responses to DTMUV infection are unclear. Therefore, we systematically examined the expression of immune-related genes and the viral distribution in DTMUV-infected ducks, using quantitative real-time PCR. Our results show that DTMUV replicates quickly in many tissues early in infection, with the highest viral titers in the spleen 1 day after infection. Rig-1, Mda5, and Tlr3 are involved in the host immune response to DTMUV, and the expression of proinflammatory cytokines (Il-1β, -2, -6, Cxcl8 and antiviral proteins (Mx, Oas, etc. are also upregulated early in infection. The expression of Il-6 increased most significantly in the tissues tested. The upregulation of Mhc-I was observed in the brain and spleen, but the expression of Mhc-II was upregulated in the brain and downregulated in the spleen. The expression of the interferons was also upregulated to different degrees in the spleen but that of the brain was various. Our study suggests that DTMUV replicates rapidly in various tissues and that the host immune responses are activated early in infection. However, the overexpression of cytokines may damage the host. These results extend our understanding of the immune responses of ducks to DTMUV infection, and provide insight into the pathogenesis of DTMUV attributable to host factors.

  18. Reanalysis of coreceptor tropism in HIV-1-infected adults using a phenotypic assay with enhanced sensitivity.

    Science.gov (United States)

    Wilkin, Timothy J; Goetz, Mathew Bidwell; Leduc, Robert; Skowron, Gail; Su, Zhaohui; Chan, Ellen S; Heera, Jayyant; Chapman, Doug; Spritzler, John; Reeves, Jacqueline D; Gulick, Roy M; Coakley, Eoin

    2011-04-01

    The enhanced-sensitivity Trofile assay (TF-ES; Monogram Biosciences) was used to retest coreceptor tropism samples from 4 different cohorts of HIV-1-infected patients. Nine percent to 26% of patients with CCR5-tropic virus by the original Trofile assay had CXCR4-using virus by TF-ES. Lower CD4 cell counts were associated with CXCR4-using virus in all cohorts. © The Author 2011. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved.

  19. A20 (Tnfaip3 deficiency in myeloid cells protects against influenza A virus infection.

    Directory of Open Access Journals (Sweden)

    Jonathan Maelfait

    Full Text Available The innate immune response provides the first line of defense against viruses and other pathogens by responding to specific microbial molecules. Influenza A virus (IAV produces double-stranded RNA as an intermediate during the replication life cycle, which activates the intracellular pathogen recognition receptor RIG-I and induces the production of proinflammatory cytokines and antiviral interferon. Understanding the mechanisms that regulate innate immune responses to IAV and other viruses is of key importance to develop novel therapeutic strategies. Here we used myeloid cell specific A20 knockout mice to examine the role of the ubiquitin-editing protein A20 in the response of myeloid cells to IAV infection. A20 deficient macrophages were hyperresponsive to double stranded RNA and IAV infection, as illustrated by enhanced NF-κB and IRF3 activation, concomitant with increased production of proinflammatory cytokines, chemokines and type I interferon. In vivo this was associated with an increased number of alveolar macrophages and neutrophils in the lungs of IAV infected mice. Surprisingly, myeloid cell specific A20 knockout mice are protected against lethal IAV infection. These results challenge the general belief that an excessive host proinflammatory response is associated with IAV-induced lethality, and suggest that under certain conditions inhibition of A20 might be of interest in the management of IAV infections.

  20. Reanalysis of Coreceptor Tropism in HIV-1–Infected Adults Using a Phenotypic Assay with Enhanced Sensitivity

    Science.gov (United States)

    Goetz, Mathew Bidwell; Leduc, Robert; Skowron, Gail; Su, Zhaohui; Chan, Ellen S.; Heera, Jayyant; Chapman, Doug; Spritzler, John; Reeves, Jacqueline D.; Gulick, Roy M.; Coakley, Eoin

    2011-01-01

    The enhanced-sensitivity Trofile assay (TF-ES; Monogram Biosciences) was used to retest coreceptor tropism samples from 4 different cohorts of HIV-1–infected patients. Nine percent to 26% of patients with CCR5-tropic virus by the original Trofile assay had CXCR4-using virus by TF-ES. Lower CD4 cell counts were associated with CXCR4-using virus in all cohorts. PMID:21427401

  1. Neutralizing and non-neutralizing monoclonal antibodies against dengue virus E protein derived from a naturally infected patient

    Directory of Open Access Journals (Sweden)

    Isern Sharon

    2010-02-01

    Full Text Available Abstract Background Antibodies produced in response to infection with any of the four serotypes of dengue virus generally provide homotypic immunity. However, prior infection or circulating maternal antibodies can also mediate a non-protective antibody response that can enhance the course of disease in a subsequent heterotypic infection. Naturally occurring human monoclonal antibodies can help us understand the protective and pathogenic roles of the humoral immune system in dengue virus infection. Results Epstein-Barr Virus (EBV transformation of B cells isolated from the peripheral blood of a human subject with previous dengue infection was performed. B cell cultures were screened by ELISA for antibodies to dengue (DENV envelope (E protein. ELISA positive cultures were cloned by limiting dilution. Three IgG1 human monoclonal antibodies (HMAbs were purified and their binding specificity to E protein was verified by ELISA and biolayer interferometry. Neutralization and enhancement assays were conducted in epithelial and macrophage-like cell lines, respectively. All three HMAbs bound to E from at least two of the four DENV serotypes, one of the HMAbs was neutralizing, and all were able to enhance DENV infection. Conclusions HMAbs against DENV can be successfully generated by EBV transformation of B cells from patients at least two years after naturally acquired DENV infections. These antibodies show different patterns of cross-reactivity, neutralizing, and enhancement activity.

  2. Experimental Oral Herpes Simplex Virus-1 (HSV-1 Co-infection in Simian Immunodeficiency Virus (SIV-Infected Rhesus Macaques

    Directory of Open Access Journals (Sweden)

    Meropi Aravantinou

    2017-12-01

    Full Text Available Herpes simplex virus 1 and 2 (HSV-1/2 similarly initiate infection in mucosal epithelia and establish lifelong neuronal latency. Anogenital HSV-2 infection augments the risk for sexual human immunodeficiency virus (HIV transmission and is associated with higher HIV viral loads. However, whether oral HSV-1 infection contributes to oral HIV susceptibility, viremia, or oral complications of HIV infection is unknown. Appropriate non-human primate (NHP models would facilitate this investigation, yet there are no published studies of HSV-1/SIV co-infection in NHPs. Thus, we performed a pilot study for an oral HSV-1 infection model in SIV-infected rhesus macaques to describe the feasibility of the modeling and resultant immunological changes. Three SIV-infected, clinically healthy macaques became HSV-1-infected by inoculation with 4 × 108 pfu HSV-1 McKrae on buccal, tongue, gingiva, and tonsils after gentle abrasion. HSV-1 DNA was shed in oral swabs for up to 21 days, and shedding recurred in association with intra-oral lesions after periods of no shedding during 56 days of follow up. HSV-1 DNA was detected in explant cultures of trigeminal ganglia collected at euthanasia on day 56. In the macaque with lowest baseline SIV viremia, SIV plasma RNA increased following HSV-1 infection. One macaque exhibited an acute pro-inflammatory response, and all three animals experienced T cell activation and mobilization in blood. However, T cell and antibody responses to HSV-1 were low and atypical. Through rigorous assessesments, this study finds that the virulent HSV-1 strain McKrae resulted in a low level HSV-1 infection that elicited modest immune responses and transiently modulated SIV infection.

  3. A novel reporter system for neutralizing and enhancing antibody assay against dengue virus.

    Science.gov (United States)

    Song, Ke-Yu; Zhao, Hui; Jiang, Zhen-You; Li, Xiao-Feng; Deng, Yong-Qiang; Jiang, Tao; Zhu, Shun-Ya; Shi, Pei-Yong; Zhang, Bo; Zhang, Fu-Chun; Qin, E-De; Qin, Cheng-Feng

    2014-02-18

    Dengue virus (DENV) still poses a global public health threat, and no vaccine or antiviral therapy is currently available. Antibody plays distinct roles in controlling DENV infections. Neutralizing antibody is protective against DENV infection, whereas sub-neutralizing concentration of antibody can increase DENV infection, termed antibody-dependent enhancement (ADE). Plaque-based assay represents the most widely accepted method measuring neutralizing or enhancing antibodies. In this study, a novel reporter virus-based system was developed for measuring neutralization and ADE activity. A stable Renilla luciferase reporter DENV (Luc-DENV) that can produce robust luciferase signals in BHK-21 and K562 cells were used to establish the assay and validated against traditional plaque-based assay. Luciferase value analysis using various known DENV-specific monoclonal antibodies showed good repeatability and a well linear correlation with conventional plaque-based assays. The newly developed assay was finally validated with clinical samples from infected animals and individuals. This reporter virus-based assay for neutralizing and enhancing antibody evaluation is rapid, lower cost, and high throughput, and will be helpful for laboratory detection and epidemiological investigation for DENV antibodies.

  4. Does reservoir host mortality enhance transmission of West Nile virus?

    Directory of Open Access Journals (Sweden)

    Foppa Ivo M

    2007-05-01

    Full Text Available Abstract Background Since its 1999 emergence in New York City, West Nile virus (WNV has become the most important and widespread cause of mosquito-transmitted disease in North America. Its sweeping spread from the Atlantic to the Pacific coast was accompanied by widespread mortality among wild birds, especially corvids. Only sporadic avian mortality had previously been associated with this infection in the Old World. Here, we examine the possibility that reservoir host mortality may intensify transmission, both by concentrating vector mosquitoes on remaining hosts and by preventing the accumulation of "herd immunity". Results Inspection of the Ross-Macdonald expression of the basic reproductive number (R0 suggests that this quantity may increase with reservoir host mortality. Computer simulation confirms this finding and indicates that the level of virulence is positively associated with the numbers of infectious mosquitoes by the end of the epizootic. The presence of reservoir incompetent hosts in even moderate numbers largely eliminated the transmission-enhancing effect of host mortality. Local host die-off may prevent mosquitoes to "waste" infectious blood meals on immune host and may thus facilitate perpetuation and spread of transmission. Conclusion Under certain conditions, host mortality may enhance transmission of WNV and similarly maintained arboviruses and thus facilitate their emergence and spread. The validity of the assumptions upon which this argument is built need to be empirically examined.

  5. Radioimmunoassay of Herpes simplex virus antibody: correlation with ganglionic infection

    International Nuclear Information System (INIS)

    Forghani, B.; Klassen, T.; Baringer, J.R.

    1977-01-01

    Results of herpes simplex virus (HSV) isolation from a series of human post-mortem trigeminal thoracic and sacral ganglia were correlated with HSV antibody type(s) detected in the sera by radioimmunoassay (RIA). HSV type I was isolated from trigeminal ganglia of 44 out of 90 individuals, from thoracic ganglia of 1 out of 25, and from sacral ganglia of 1 out of 68 cases. HSV type was recovered from sacral ganglia of 8 out of 68 individuals. In all cases in which an HSV was isolated from ganglia and was available for testing, homologous, type-specific antibody was demonstrable, and in a few instances antibody to the heterologous HSV was also detected. In those individuals in which HSV type I was isolated from trigeminal ganglia and HSV type 2 from sacral ganglia, antibody to both virus types was present in the sera, indicating that simultaneous latent infections with each of the two viruses can occur, and that antibody is produced to each virus independently. Antibody to HSV type 1, 2 or both types was demonstrated in 8 out of 10 cases in which virus isolation attempts were negative, suggesting either a higher sensitivity of RIA for detecting HSV infection, or the presence of latent HSV at some other site in the body which was not sampled. (author)

  6. High Infection Rates for Adult Macaques after Intravaginal or Intrarectal Inoculation with Zika Virus

    Science.gov (United States)

    Nalca, Aysegul; Rossi, Franco D.; Miller, Lynn J.; Wiley, Michael R.; Perez-Sautu, Unai; Washington, Samuel C.; Norris, Sarah L.; Wollen-Roberts, Suzanne E.; Shamblin, Joshua D.; Kimmel, Adrienne E.; Bloomfield, Holly A.; Valdez, Stephanie M.; Sprague, Thomas R.; Principe, Lucia M.; Bellanca, Stephanie A.; Cinkovich, Stephanie S.; Lugo-Roman, Luis; Cazares, Lisa H.; Pratt, William D.; Palacios, Gustavo F.; Bavari, Sina; Pitt, M. Louise; Nasar, Farooq

    2017-01-01

    Unprotected sexual intercourse between persons residing in or traveling from regions with Zika virus transmission is a risk factor for infection. To model risk for infection after sexual intercourse, we inoculated rhesus and cynomolgus macaques with Zika virus by intravaginal or intrarectal routes. In macaques inoculated intravaginally, we detected viremia and virus RNA in 50% of macaques, followed by seroconversion. In macaques inoculated intrarectally, we detected viremia, virus RNA, or both, in 100% of both species, followed by seroconversion. The magnitude and duration of infectious virus in the blood of macaques suggest humans infected with Zika virus through sexual transmission will likely generate viremias sufficient to infect competent mosquito vectors. Our results indicate that transmission of Zika virus by sexual intercourse might serve as a virus maintenance mechanism in the absence of mosquito-to-human transmission and could increase the probability of establishment and spread of Zika virus in regions where this virus is not present. PMID:28548637

  7. High Infection Rates for Adult Macaques after Intravaginal or Intrarectal Inoculation with Zika Virus.

    Science.gov (United States)

    Haddow, Andrew D; Nalca, Aysegul; Rossi, Franco D; Miller, Lynn J; Wiley, Michael R; Perez-Sautu, Unai; Washington, Samuel C; Norris, Sarah L; Wollen-Roberts, Suzanne E; Shamblin, Joshua D; Kimmel, Adrienne E; Bloomfield, Holly A; Valdez, Stephanie M; Sprague, Thomas R; Principe, Lucia M; Bellanca, Stephanie A; Cinkovich, Stephanie S; Lugo-Roman, Luis; Cazares, Lisa H; Pratt, William D; Palacios, Gustavo F; Bavari, Sina; Pitt, M Louise; Nasar, Farooq

    2017-08-01

    Unprotected sexual intercourse between persons residing in or traveling from regions with Zika virus transmission is a risk factor for infection. To model risk for infection after sexual intercourse, we inoculated rhesus and cynomolgus macaques with Zika virus by intravaginal or intrarectal routes. In macaques inoculated intravaginally, we detected viremia and virus RNA in 50% of macaques, followed by seroconversion. In macaques inoculated intrarectally, we detected viremia, virus RNA, or both, in 100% of both species, followed by seroconversion. The magnitude and duration of infectious virus in the blood of macaques suggest humans infected with Zika virus through sexual transmission will likely generate viremias sufficient to infect competent mosquito vectors. Our results indicate that transmission of Zika virus by sexual intercourse might serve as a virus maintenance mechanism in the absence of mosquito-to-human transmission and could increase the probability of establishment and spread of Zika virus in regions where this virus is not present.

  8. Proteasome Inhibition Suppresses Dengue Virus Egress in Antibody Dependent Infection.

    Directory of Open Access Journals (Sweden)

    Milly M Choy

    2015-11-01

    Full Text Available The mosquito-borne dengue virus (DENV is a cause of significant global health burden, with an estimated 390 million infections occurring annually. However, no licensed vaccine or specific antiviral treatment for dengue is available. DENV interacts with host cell factors to complete its life cycle although this virus-host interplay remains to be fully elucidated. Many studies have identified the ubiquitin proteasome pathway (UPP to be important for successful DENV production, but how the UPP contributes to DENV life cycle as host factors remains ill defined. We show here that proteasome inhibition decouples infectious virus production from viral RNA replication in antibody-dependent infection of THP-1 cells. Molecular and imaging analyses in β-lactone treated THP-1 cells suggest that proteasome function does not prevent virus assembly but rather DENV egress. Intriguingly, the licensed proteasome inhibitor, bortezomib, is able to inhibit DENV titers at low nanomolar drug concentrations for different strains of all four serotypes of DENV in primary monocytes. Furthermore, bortezomib treatment of DENV-infected mice inhibited the spread of DENV in the spleen as well as the overall pathological changes. Our findings suggest that preventing DENV egress through proteasome inhibition could be a suitable therapeutic strategy against dengue.

  9. Controlled human infection models for vaccine development: Zika virus debate.

    Science.gov (United States)

    Gopichandran, Vijayaprasad

    2018-01-01

    An ethics panel, convened by the National Institute of Health and other research bodies in the USA, disallowed researchers from the Johns Hopkins University and University of Vermont from performing controlled human infection of healthy volunteers to develop a vaccine against Zika virus infection. The members published their ethical analysis and recommendations in February 2017. They have elaborated on the risks posed by human challenge with Zika virus to the volunteers and other uninvolved third parties and have systematically analysed the social value of such a human challenge experiment. They have also posited some mandatory ethical requirements which should be met before allowing the infection of healthy volunteers with the Zika virus. This commentary elaborates on the debate on the ethics of the human challenge model for the development of a Zika virus vaccine and the role of systematic ethical analysis in protecting the interests of research participants. It further analyses the importance of this debate to the development of a Zika vaccine in India.

  10. Clinical aspects of feline immunodeficiency and feline leukemia virus infection.

    Science.gov (United States)

    Hartmann, Katrin

    2011-10-15

    Feline leukemia virus (FeLV) and feline immunodeficiency virus (FIV) are retroviruses with a global impact on the health of domestic cats. The two viruses differ in their potential to cause disease. FIV can cause an acquired immunodeficiency syndrome that increases the risk of developing opportunistic infections, neurological diseases, and tumors. In most naturally infected cats, however, FIV itself does not cause severe clinical signs, and FIV-infected cats may live many years without any health problems. FeLV is more pathogenic, and was long considered to be responsible for more clinical syndromes than any other agent in cats. FeLV can cause tumors (mainly lymphoma), bone marrow suppression syndromes (mainly anemia) and lead to secondary infectious diseases caused by suppressive effects of the virus on bone marrow and the immune system. Today, FeLV is less important as a deadly infectious agent as in the last 20 years prevalence has been decreasing in most countries. Copyright © 2011 Elsevier B.V. All rights reserved.

  11. Human immunodeficiency virus infection occupational post ... - Ibadan

    African Journals Online (AJOL)

    However, health care workers who are occupationally exposed to HIV infection must have immediate access to post-exposure prophylaxis (PEP). The risk of HIV transmission through the route of injury sustained must be assessed and adequate management given. Postexposure prophylaxis (PEP) should be commenced ...

  12. Characterization of Lethal Zika Virus Infection in AG129 Mice.

    Directory of Open Access Journals (Sweden)

    Matthew T Aliota

    2016-04-01

    Full Text Available Mosquito-borne Zika virus (ZIKV typically causes a mild and self-limiting illness known as Zika fever, which often is accompanied by maculopapular rash, headache, and myalgia. During the current outbreak in South America, ZIKV infection during pregnancy has been hypothesized to cause microcephaly and other diseases. The detection of ZIKV in fetal brain tissue supports this hypothesis. Because human infections with ZIKV historically have remained sporadic and, until recently, have been limited to small-scale epidemics, neither the disease caused by ZIKV nor the molecular determinants of virulence and/or pathogenicity have been well characterized. Here, we describe a small animal model for wild-type ZIKV of the Asian lineage.Using mice deficient in interferon α/β and Ɣ receptors (AG129 mice, we report that these animals were highly susceptible to ZIKV infection and disease, succumbing within seven to eight days. Rapid viremic dissemination was observed in visceral organs and brain; but only was associated with severe pathologies in the brain and muscle. Finally, these results were consistent across challenge routes, age of mice, and inoculum doses. These data represent a mouse model for ZIKV that is not dependent on adapting ZIKV to intracerebral passage in mice.Foot pad injection of AG129 mice with ZIKV represents a biologically relevant model for studying ZIKV infection and disease development following wild-type virus inoculation without the requirement for adaptation of the virus or intracerebral delivery of the virus. This newly developed Zika disease model can be exploited to identify determinants of ZIKV virulence and reveal molecular mechanisms that control the virus-host interaction, providing a framework for rational design of acute phase therapeutics and for vaccine efficacy testing.

  13. Role of Natural Killer Cells in Innate Protection against Lethal Ebola Virus Infection

    OpenAIRE

    Warfield, Kelly L.; Perkins, Jeremy G.; Swenson, Dana L.; Deal, Emily M.; Bosio, Catharine M.; Aman, M. Javad; Yokoyama, Wayne M.; Young, Howard A.; Bavari, Sina

    2004-01-01

    Ebola virus is a highly lethal human pathogen and is rapidly driving many wild primate populations toward extinction. Several lines of evidence suggest that innate, nonspecific host factors are potentially critical for survival after Ebola virus infection. Here, we show that nonreplicating Ebola virus-like particles (VLPs), containing the glycoprotein (GP) and matrix protein virus protein (VP)40, administered 1–3 d before Ebola virus infection rapidly induced protective immunity. VLP injectio...

  14. Dengue virus serotype 2 infection alters midgut and carcass gene expression in the Asian tiger mosquito, Aedes albopictus.

    Directory of Open Access Journals (Sweden)

    Hitoshi Tsujimoto

    Full Text Available The Asian tiger mosquito, Aedes albopictus is currently an important vector for dengue, chikungunya and Zika virus, and its role in transmission of arthropod-borne viruses (arboviruses may increase in the future due to its ability to colonize temperate regions. In contrast to Aedes aegypti, the dominant vector of dengue, chikungunya and Zika virus, genetic responses of Ae. albopictus upon infection with an arbovirus are not well characterized. Here we present a study of the changes in transcript expression in Ae. albopictus exposed to dengue virus serotype 2 via feeding on an artificial bloodmeal.We isolated midguts and midgut-free carcasses of Ae. albopictus fed on bloodmeals containing dengue virus as well as controls fed on virus-free control meals at day 1 and day 5 post-feeding. We confirmed infection of midguts from mosquitoes sampled on day 5 post-feeding via RT-PCR. RNAseq analysis revealed dynamic modulation of the expression of several putative immunity and dengue virus-responsive genes, some of whose expression was verified by qRT-PCR. For example, a serine protease gene was up-regulated in the midgut at 1 day post infection, which may potentially enhance mosquito susceptibility to dengue infection, while 14 leucine-rich repeat genes, previously shown to be involved in mosquito antiviral defenses, were down-regulated in the carcass at 5 days post infection. The number of significantly modulated genes decreased over time in midguts and increased in carcasses.Dengue virus exposure results in the modulation of genes in a time- and site-specific manner. Previous literature on the interaction between mosquitoes and mosquito-borne pathogens suggests that most of the changes that occurred in Ae. albopictus exposed to DENV would favor virus infection. Many genes identified in this study warrant further characterization to understand their role in viral manipulation of and antiviral response of Ae. albopictus.

  15. Association between microcephaly, Zika virus infection, and other risk factors in Brazil: final report of a case-control study.

    Science.gov (United States)

    de Araújo, Thalia Velho Barreto; Ximenes, Ricardo Arraes de Alencar; Miranda-Filho, Demócrito de Barros; Souza, Wayner Vieira; Montarroyos, Ulisses Ramos; de Melo, Ana Paula Lopes; Valongueiro, Sandra; de Albuquerque, Maria de Fátima Pessoa Militão; Braga, Cynthia; Filho, Sinval Pinto Brandão; Cordeiro, Marli Tenório; Vazquez, Enrique; Cruz, Danielle di Cavalcanti Souza; Henriques, Claudio Maierovitch Pessanha; Bezerra, Luciana Caroline Albuquerque; Castanha, Priscila Mayrelle da Silva; Dhalia, Rafael; Marques-Júnior, Ernesto Torres Azevedo; Martelli, Celina Maria Turchi; Rodrigues, Laura Cunha

    2018-03-01

    and had cerebral abnormalities, 13 were positive for Zika infection but had no cerebral abnormalities, and 11 were negative for Zika virus but had cerebral abnormalities. The association between microcephaly and congenital Zika virus infection was confirmed. We provide evidence of the absence of an effect of other potential factors, such as exposure to pyriproxyfen or vaccines (tetanus, diphtheria, and acellular pertussis, measles and rubella, or measles, mumps, and rubella) during pregnancy, confirming the findings of an ecological study of pyriproxyfen in Pernambuco and previous studies on the safety of Tdap vaccine administration during pregnancy. Brazilian Ministry of Health, Pan American Health Organization, and Enhancing Research Activity in Epidemic Situations. Copyright © 2018 Elsevier Ltd. All rights reserved.

  16. Outbreak of hepatitis C virus infection associated with narcotics diversion by an hepatitis C virus-infected surgical technician.

    Science.gov (United States)

    Warner, Amy E; Schaefer, Melissa K; Patel, Priti R; Drobeniuc, Jan; Xia, Guoliang; Lin, Yulin; Khudyakov, Yury; Vonderwahl, Candace W; Miller, Lisa; Thompson, Nicola D

    2015-01-01

    Drug diversion by health care personnel poses a risk for serious patient harm. Public health identified 2 patients diagnosed with acute hepatitis C virus (HCV) infection who shared a common link with a hospital. Further investigation implicated a drug-diverting, HCV-infected surgical technician who was subsequently employed at an ambulatory surgical center. Patients at the 2 facilities were offered testing for HCV infection if they were potentially exposed. Serum from the surgical technician and patients testing positive for HCV but without evidence of infection before their surgical procedure was further tested to determine HCV genotype and quasi-species sequences. Parenteral medication handling practices at the 2 facilities were evaluated. The 2 facilities notified 5970 patients of their possible exposure to HCV, 88% of whom were tested and had results reported to the state public health departments. Eighteen patients had HCV highly related to the surgical technician's virus. The surgical technician gained unauthorized access to fentanyl owing to limitations in procedures for securing controlled substances. Public health surveillance identified an outbreak of HCV infection due to an infected health care provider engaged in diversion of injectable narcotics. The investigation highlights the value of public health surveillance in identifying HCV outbreaks and uncovering a method of drug diversion and its impacts on patients. Copyright © 2015 Association for Professionals in Infection Control and Epidemiology, Inc. All rights reserved.

  17. Virus-neutralizing antibody response of mice to consecutive infection with human and avian influenza A viruses.

    Science.gov (United States)

    Janulíková, J; Stropkovská, A; Bobišová, Z; Košík, I; Mucha, V; Kostolanský, F; Varečková, E

    2015-06-01

    In this work we simulated in a mouse model a naturally occurring situation of humans, who overcame an infection with epidemic strains of influenza A, and were subsequently exposed to avian influenza A viruses (IAV). The antibody response to avian IAV in mice previously infected with human IAV was analyzed. We used two avian IAV (A/Duck/Czechoslovakia/1956 (H4N6) and the attenuated virus rA/Viet Nam/1203-2004 (H5N1)) as well as two human IAV isolates (virus A/Mississippi/1/1985 (H3N2) of medium virulence and A/Puerto Rico/8/1934 (H1N1) of high virulence). Two repeated doses of IAV of H4 or of H5 virus elicited virus-specific neutralizing antibodies in mice. Exposure of animals previously infected with human IAV (of H3 or H1 subtype) to IAV of H4 subtype led to the production of antibodies neutralizing H4 virus in a level comparable with the level of antibodies against the human IAV used for primary infection. In contrast, no measurable levels of virus-neutralizing (VN) antibodies specific to H5 virus were detected in mice infected with H5 virus following a previous infection with human IAV. In both cases the secondary infection with avian IAV led to a significant increase of the titer of VN antibodies specific to the corresponding human virus used for primary infection. Moreover, cross-reactive HA2-specific antibodies were also induced by sequential infection. By virtue of these results we suggest that the differences in the ability of avian IAV to induce specific antibodies inhibiting virus replication after previous infection of mice with human viruses can have an impact on the interspecies transmission and spread of avian IAV in the human population.

  18. Viruses that enhance the aethetics of some ornamental plants: beauty or beast?

    Science.gov (United States)

    Although most viruses that infect plants cause diseases that are detrimental to the plant, there are some instances in which infections by mild viral strains of a virus have been used to protect the plant against severe strains of the same virus. There are other viruses that can cause desirable effe...

  19. Chayote mosaic virus, a New Tymovirus Infecting Cucurbitaceae.

    Science.gov (United States)

    Bernal, J J; Jiménez, I; Moreno, M; Hord, M; Rivera, C; Koenig, R; Rodríguez-Cerezo, E

    2000-10-01

    ABSTRACT Chayote mosaic virus (ChMV) is a putative tymovirus isolated from chayote crops in Costa Rica. ChMV was characterized at the host range, serological, and molecular levels. ChMV was transmitted mechanically and induced disease symptoms mainly in Cucurbitaceae hosts. Asymptomatic infections were detected in other host families. Serologically, ChMV is related to the Andean potato latent virus (APLV) and the Eggplant mosaic virus (EMV), both members of the genus Tymovirus infecting solanaceous hosts in the Caribbean Basin and South America. The sequence of the genomic RNA of ChMV was determined and its genetic organization was typical of tymoviruses. Comparisons with other tymoviral sequences showed that ChMV was a new member of the genus Tymovirus. The phylogenetic analyses of the coat protein gene were consistent with serological comparisons and positioned ChMV within a cluster of tymoviruses infecting mainly cucurbit or solanaceous hosts, including APLV and EMV. Phylogenetic analyses of the replicase protein gene confirmed the close relationship of ChMV and EMV. Our results suggest that ChMV is related to two tymoviruses (APLV and EMV) of proximal geographical provenance but with different natural host ranges. ChMV is the first cucurbit-infecting tymovirus to be fully characterized at the genomic level.

  20. Ageratum enation virus Infection Induces Programmed Cell Death and Alters Metabolite Biosynthesis in Papaver somniferum

    Directory of Open Access Journals (Sweden)

    Ashish Srivastava

    2017-07-01

    Full Text Available A previously unknown disease which causes severe vein thickening and inward leaf curl was observed in a number of opium poppy (Papaver somniferum L. plants. The sequence analysis of full-length viral genome and associated betasatellite reveals the occurrence of Ageratum enation virus (AEV and Ageratum leaf curl betasatellite (ALCB, respectively. Co-infiltration of cloned agroinfectious DNAs of AEV and ALCB induces the leaf curl and vein thickening symptoms as were observed naturally. Infectivity assay confirmed this complex as the cause of disease and also satisfied the Koch’s postulates. Comprehensive microscopic analysis of infiltrated plants reveals severe structural anomalies in leaf and stem tissues represented by unorganized cell architecture and vascular bundles. Moreover, the characteristic blebs and membranous vesicles formed due to the virus-induced disintegration of the plasma membrane and intracellular organelles were also present. An accelerated nuclear DNA fragmentation was observed by Comet assay and confirmed by TUNEL and Hoechst dye staining assays suggesting virus-induced programmed cell death. Virus-infection altered the biosynthesis of several important metabolites. The biosynthesis potential of morphine, thebaine, codeine, and papaverine alkaloids reduced significantly in infected plants except for noscapine whose biosynthesis was comparatively enhanced. The expression analysis of corresponding alkaloid pathway genes by real time-PCR corroborated well with the results of HPLC analysis for alkaloid perturbations. The changes in the metabolite and alkaloid contents affect the commercial value of the poppy plants.

  1. Molecular Biology and Infection of Hepatitis E Virus

    Directory of Open Access Journals (Sweden)

    Yuchen Nan

    2016-09-01

    Full Text Available Hepatitis E virus (HEV is a viral pathogen transmitted primarily via fecal-oral route. In humans, HEV mainly causes acute hepatitis and is responsible for large outbreaks of hepatitis across the world. The case fatality rate of HEV-induced hepatitis ranges from 0.5 to 3% in young adults and up to 30% in infected pregnant women. HEV strains infecting humans are classified into four genotypes. HEV strains from genotype 3 and 4 are zoonotic, whereas those from genotype 1 and 2 have no known animal reservoirs. Recently, notable progress has been accomplished for better understanding of HEV biology and infection, such as chronic HEV infection, in vitro cell culture system, quasi-enveloped HEV virions, functions of the HEV proteins, mechanism of HEV antagonizing host innate immunity, HEV pathogenesis and vaccine development. However, further investigation on the cross-species HEV infection, host tropism, vaccine efficacy and HEV-specific antiviral strategy is still needed. This review mainly focuses on molecular biology and infection of HEV and offers perspective new insight of this enigmatic virus.

  2. Modeling Powassan virus infection in Peromyscus leucopus, a natural host.

    Directory of Open Access Journals (Sweden)

    Luwanika Mlera

    2017-01-01

    Full Text Available The tick-borne flavivirus, Powassan virus (POWV causes life-threatening encephalitis in humans in North America and Europe. POWV is transmitted by ixodid tick vectors that feed on small to medium-sized mammals, such as Peromyscus leucopus mice, which may serve as either reservoir, bridge or amplification hosts. Intraperitoneal and intracranial inoculation of 4-week old Peromyscus leucopus mice with 103 PFU of POWV did not result in overt clinical signs of disease. However, following intracranial inoculation, infected mice seroconverted to POWV and histopathological examinations revealed that the mice uniformly developed mild lymphocytic perivascular cuffing and microgliosis in the brain and spinal cord from 5 to 15 days post infection (dpi, suggesting an early inflammatory response. In contrast, intracranial inoculation of 4-week old C57BL/6 and BALB/c mice was lethal by 5 dpi. Intraperitoneal inoculation was lethal in BALB/c mice, but 40% (2/5 of C57BL/6 mice survived. We concluded that Peromyscus leucopus mice infected i.c. with a lethal dose of POWV support a limited infection, restricted to the central nervous system and mount an antibody response to the virus. However, they fail to develop clinical signs of disease and are able to control the infection. These results suggest the involvement of restriction factors, and the mechanism by which Peromyscus leucopus mice restrict POWV infection remains under study.

  3. Localization of influenza virus proteins to nuclear dot 10 structures in influenza virus-infected cells

    International Nuclear Information System (INIS)

    Sato, Yoshiko; Yoshioka, Kenichi; Suzuki, Chie; Awashima, Satoshi; Hosaka, Yasuhiro; Yewdell, Jonathan; Kuroda, Kazumichi

    2003-01-01

    We studied influenza virus M1 protein by generating HeLa and MDCK cell lines that express M1 genetically fused to green fluorescent protein (GFP). GFP-M1 was incorporated into virions produced by influenza virus infected MDCK cells expressing the fusion protein indicating that the fusion protein is at least partially functional. Following infection of either HeLa or MDCK cells with influenza A virus (but not influenza B virus), GFP-M1 redistributes from its cytosolic/nuclear location and accumulates in nuclear dots. Immunofluorescence revealed that the nuclear dots represent nuclear dot 10 (ND10) structures. The colocalization of authentic M1, as well as NS1 and NS2 protein, with ND10 was confirmed by immunofluorescence following in situ isolation of ND10. These findings demonstrate a previously unappreciated involvement of influenza virus with ND10, a structure involved in cellular responses to immune cytokines as well as the replication of a rapidly increasing list of viruses

  4. Case report: microcephaly associated with Zika virus infection, Colombia.

    Science.gov (United States)

    Mattar, Salim; Ojeda, Carolina; Arboleda, Janna; Arrieta, German; Bosch, Irene; Botia, Ingrid; Alvis-Guzman, Nelson; Perez-Yepes, Carlos; Gerhke, Lee; Montero, German

    2017-06-13

    Recently there has been a large outbreak of Zika virus infections in Colombia, South America. The epidemic began in September 2015 and continued to April 2017, for the total number of Zika cases reported of 107,870. For those confirmed Zika cases, there were nearly 20,000 (18.5%) suspected to be pregnant women, resulting in 157 confirmed cases of microcephaly in newborns reported by their health government agency. There is a clear under-estimation of the total number of cases and in addition no prior publications have been published to demonstrate the clinical aspects of the Zika infection in Colombia. We characterized one Zika presentation to be able to compare and contrast with other cases of Zika infection already reported in the literature. In this case report, we demonstrate congenital microcephaly at week 19 of gestation in a 34-year-old mother who showed symptoms compatible with Zika virus infection from Sincelejo, State of Sucre, in the Colombian Caribbean. Zika virus RNA was detected in the placenta using real-time reverse transcriptase polymerase chain reaction (RT-PCR). At week 25, the fetus weigh estimate was 770 g, had a cephalic perimeter of 20.2 cm (5th percentile), ventriculomegaly on the right side and dilatation of the fourth ventricle. At week 32, the microcephaly was confirmed with a cephalic perimeter of 22 cm, dilatation of the posterior atrium to 13 mm, an abnormally small cerebellum (29 mm), and an augmented cisterna magna. At birth (39 weeks by cesarean section), the head circumference was 27.5 cm, and computerized axial tomography (Siemens Corp, 32-slides) confirmed microcephaly with calcifications. We report a first case of maternal Zika virus infection associated with fetal microcephaly in Colombia and confirmed similar presentation to those observed previous in Brazil, 2015-2016.

  5. West Nile virus infection of birds, Mexico.

    Science.gov (United States)

    Guerrero-Sánchez, Sergio; Cuevas-Romero, Sandra; Nemeth, Nicole M; Trujillo-Olivera, María Teresa Jesús; Worwa, Gabriella; Dupuis, Alan; Brault, Aaron C; Kramer, Laura D; Komar, Nicholas; Estrada-Franco, José Guillermo

    2011-12-01

    West Nile virus (WNV) has caused disease in humans, equids, and birds at lower frequency in Mexico than in the United States. We hypothesized that the seemingly reduced virulence in Mexico was caused by attenuation of the Tabasco strain from southeastern Mexico, resulting in lower viremia than that caused by the Tecate strain from the more northern location of Baja California. During 2006-2008, we tested this hypothesis in candidate avian amplifying hosts: domestic chickens, rock pigeons, house sparrows, great-tailed grackles, and clay-colored thrushes. Only great-tailed grackles and house sparrows were competent amplifying hosts for both strains, and deaths occurred in each species. Tecate strain viremia levels were higher for thrushes. Both strains produced low-level viremia in pigeons and chickens. Our results suggest that certain avian hosts within Mexico are competent for efficient amplification of both northern and southern WNV strains and that both strains likely contribute to bird deaths.

  6. Ferrets Infected with Bundibugyo Virus or Ebola Virus Recapitulate Important Aspects of Human Filovirus Disease.

    Science.gov (United States)

    Kozak, Robert; He, Shihua; Kroeker, Andrea; de La Vega, Marc-Antoine; Audet, Jonathan; Wong, Gary; Urfano, Chantel; Antonation, Kym; Embury-Hyatt, Carissa; Kobinger, Gary P; Qiu, Xiangguo

    2016-10-15

    Bundibugyo virus (BDBV) is the etiological agent of a severe hemorrhagic fever in humans with a case-fatality rate ranging from 25 to 36%. Despite having been known to the scientific and medical communities for almost 1 decade, there is a dearth of studies on this pathogen due to the lack of a small animal model. Domestic ferrets are commonly used to study other RNA viruses, including members of the order Mononegavirales To investigate whether ferrets were susceptible to filovirus infections, ferrets were challenged with a clinical isolate of BDBV. Animals became viremic within 4 days and succumbed to infection between 8 and 9 days, and a petechial rash was observed with moribund ferrets. Furthermore, several hallmarks of human filoviral disease were recapitulated in the ferret model, including substantial decreases in lymphocyte and platelet counts and dysregulation of key biochemical markers related to hepatic/renal function, as well as coagulation abnormalities. Virological, histopathological, and immunohistochemical analyses confirmed uncontrolled BDBV replication in the major organs. Ferrets were also infected with Ebola virus (EBOV) to confirm their susceptibility to another filovirus species and to potentially establish a virus transmission model. Similar to what was seen with BDBV, important hallmarks of human filoviral disease were observed in EBOV-infected ferrets. This study demonstrates the potential of this small animal model for studying BDBV and EBOV using wild-type isolates and will accelerate efforts to understand filovirus pathogenesis and transmission as well as the development of specific vaccines and antivirals. The 2013-2016 outbreak of Ebola virus in West Africa has highlighted the threat posed by filoviruses to global public health. Bundibugyo virus (BDBV) is a member of the genus Ebolavirus and has caused outbreaks in the past but is relatively understudied, likely due to the lack of a suitable small animal model. Such a model for BDBV is

  7. Begomoviruses infecting weeds in Cuba: increased host range and a novel virus infecting Sida rhombifolia.

    Science.gov (United States)

    Fiallo-Olivé, Elvira; Navas-Castillo, Jesús; Moriones, Enrique; Martínez-Zubiaur, Yamila

    2012-01-01

    As a result of surveys conducted during the last few years to search for wild reservoirs of begomoviruses in Cuba, we detected a novel bipartite begomovirus, sida yellow mottle virus (SiYMoV), infecting Sida rhombifolia plants. The complete genome sequence was obtained, showing that DNA-A was 2622 nucleotides (nt) in length and that it was most closely related (87.6% nucleotide identity) to DNA-A of an isolate of sida golden mosaic virus (SiGMV) that infects snap beans (Phaseolus vulgaris) in Florida. The DNA-B sequence was 2600 nt in length and shared the highest nucleotide identity (75.1%) with corchorus yellow spot virus (CoYSV). Phylogenetic relationship analysis showed that both DNA components of SiYMoV were grouped in the Abutilon clade, along with begomoviruses from Florida and the Caribbean islands. We also present here the complete nucleotide sequence of a novel strain of sida yellow vein virus found infecting Malvastrum coromandelianum and an isolate of euphorbia mosaic virus that was found for the first time infecting Euphorbia heterophylla in Cuba.

  8. Epidemiology and Transmission of Hepatitis A Virus and Hepatitis E Virus Infections in the United States.

    Science.gov (United States)

    Hofmeister, Megan G; Foster, Monique A; Teshale, Eyasu H

    2018-04-30

    There are many similarities in the epidemiology and transmission of hepatitis A virus (HAV) and hepatitis E virus (HEV) genotype (gt)3 infections in the United States. Both viruses are enterically transmitted, although specific routes of transmission are more clearly established for HAV than for HEV: HAV is restricted to humans and primarily spread through the fecal-oral route, while HEV is zoonotic with poorly understood modes of transmission in the United States. New cases of HAV infection have decreased dramatically in the United States since infant vaccination was recommended in 1996. In recent years, however, outbreaks have occurred among an increasingly susceptible adult population. Although HEV is the most common cause of acute viral hepatitis in developing countries, it is rarely diagnosed in the United States. Copyright © 2018 Cold Spring Harbor Laboratory Press; all rights reserved.

  9. Seroprevalence of feline leukemia virus and feline immunodeficiency virus infection among cats in Canada.

    Science.gov (United States)

    Little, Susan; Sears, William; Lachtara, Jessica; Bienzle, Dorothee

    2009-06-01

    The purposes of this study were to determine the seroprevalence of feline leukemia virus (FeLV) and feline immunodeficiency virus (FIV) infection among cats in Canada and to identify risk factors for seropositivity. Signalment, lifestyle factors, and test results for FeLV antigen and FIV antibody were analyzed for 11 144 cats from the 10 Canadian provinces. Seroprevalence for FIV antibody was 4.3% and seroprevalence for FeLV antigen was 3.4%. Fifty-eight cats (0.5%) were seropositive for both viruses. Seroprevalence varied geographically. Factors such as age, gender, health status, and lifestyle were significantly associated with risk of FeLV and FIV seropositivity. The results suggest that cats in Canada are at risk of retrovirus infection and support current recommendations that the retrovirus status of all cats should be known.

  10. Cyclophilin B enhances HIV-1 infection.

    Science.gov (United States)

    DeBoer, Jason; Madson, Christian J; Belshan, Michael

    2016-02-01

    Cyclophilin B (CypB) is a member of the immunophilin family and intracellular chaperone. It predominantly localizes to the ER, but also contains a nuclear localization signal and is secreted from cells. CypB has been shown to interact with the Gag protein of human immunodeficiency type 1 (HIV-1). Several proteomic and genetic studies identified it as a potential factor involved in HIV replication. Herein, we show that over-expression of CypB enhances HIV infection by increasing nuclear import of viral DNA. This enhancement was unaffected by cyclosporine treatment and requires the N-terminus of the protein. The N-terminus contains an ER leader sequence, putative nuclear localization signal, and is required for secretion. Deletion of the N-terminus resulted in mislocalization from the ER and suppression of HIV infection. Passive transfer experiments showed that secreted CypB did not impact HIV infection. Combined, these experiments show that intracellular CypB modulates a pathway of HIV nuclear import. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. Nipah virus infection and glycoprotein targeting in endothelial cells

    Directory of Open Access Journals (Sweden)

    Maisner Andrea

    2010-11-01

    Full Text Available Abstract Background The highly pathogenic Nipah virus (NiV causes fatal respiratory and brain infections in animals and humans. The major hallmark of the infection is a systemic endothelial infection, predominantly in the CNS. Infection of brain endothelial cells allows the virus to overcome the blood-brain-barrier (BBB and to subsequently infect the brain parenchyma. However, the mechanisms of NiV replication in endothelial cells are poorly elucidated. We have shown recently that the bipolar or basolateral expression of the NiV surface glycoproteins F and G in polarized epithelial cell layers is involved in lateral virus spread via cell-to-cell fusion and that correct sorting depends on tyrosine-dependent targeting signals in the cytoplasmic tails of the glycoproteins. Since endothelial cells share many characteristics with epithelial cells in terms of polarization and protein sorting, we wanted to elucidate the role of the NiV glycoprotein targeting signals in endothelial cells. Results As observed in vivo, NiV infection of endothelial cells induced syncytia formation. The further finding that infection increased the transendothelial permeability supports the idea of spread of infection via cell-to-cell fusion and endothelial cell damage as a mechanism to overcome the BBB. We then revealed that both glycoproteins are expressed at lateral cell junctions (bipolar, not only in NiV-infected primary endothelial cells but also upon stable expression in immortalized endothelial cells. Interestingly, mutation of tyrosines 525 and 542/543 in the cytoplasmic tail of the F protein led to an apical redistribution of the protein in endothelial cells whereas tyrosine mutations in the G protein had no effect at all. This fully contrasts the previous results in epithelial cells where tyrosine 525 in the F, and tyrosines 28/29 in the G protein were required for correct targeting. Conclusion We conclude that the NiV glycoprotein distribution is responsible for

  12. Enhanced sensitivity in detection of antiviral antibody responses using biotinylation of foot-and-mouth disease virus (FMDV) capsids.

    Science.gov (United States)

    Kenney, Mary; Waters, Ryan A; Rieder, Elizabeth; Pega, Juan; Perez-Filguera, Mariano; Golde, William T

    2017-11-01

    Analysis of the immune response to infection of livestock by foot-and-mouth disease virus (FMDV) is most often reported as the serum antibody response to the virus. While measurement of neutralizing antibody has been sensitive and specific, measurements of the quality of the antibody response are less robust. Determining the immunoglobulin (Ig) isotype of the serum antibody response provides a deeper understanding of the biology of the response and more sensitive methods for these assays will facilitate analyses of B cell mediated immunity. We tested the hypothesis that using the virus as the molecular probe could be achieved by adding tags to the surface of the FMDV capsid, and that would enhance sensitivity in assays for anti-FMDV antibody responses. The use of a FLAG-tagged virus in these assays failed to yield improvement whereas chemically biotinylating the virus capsid resulted in significant enhancement of the signal. Here we describe methods using biotinylated virus for measuring anti-viral antibody in serum and antibody secreting cells (ASCs) in blood that are sensitive and specific. Finally, we describe using the biotinylated virus in flow cytometry where such assays should greatly enhance the analysis of anti-virus antibody producing B cells, allowing the investigator to focus on only the FMDV specific B cells when analyzing the development of the B cell response to either infection or vaccination. Published by Elsevier B.V.

  13. Antiviral therapy during primary simian immunodeficiency virus infection fails to prevent acute loss of CD4+ T cells in gut mucosa but enhances their rapid restoration through central memory T cells.

    Science.gov (United States)

    Verhoeven, David; Sankaran, Sumathi; Silvey, Melanie; Dandekar, Satya

    2008-04-01

    Gut-associated lymphoid tissue (GALT) is an early target of human immunodeficiency virus (HIV) and simian immunodeficiency virus (SIV) and a site for severe CD4+ T-cell depletion. Although antiretroviral therapy (ART) is effective in suppressing HIV replication and restoring CD4+ T cells in peripheral blood, restoration in GALT is delayed. The role of restored CD4+ T-cell help in GALT during ART and its impact on antiviral CD8+ T-cell responses have not been investigated. Using the SIV model, we investigated gut CD4+ T-cell restoration in infected macaques, initiating ART during either the primary stage (1 week postinfection), prior to acute CD4+ cell loss (PSI), or during the chronic stage at 10 weeks postinfection (CSI). ART led to viral suppression in GALT and peripheral blood mononuclear cells of PSI and CSI animals at comparable levels. CSI animals had incomplete CD4+ T-cell restoration in GALT. In PSI animals, ART did not prevent acute CD4+ T-cell loss by 2 weeks postinfection in GALT but supported rapid and complete CD4+ T-cell restoration thereafter. This correlated with an accumulation of central memory CD4+ T cells and better suppression of inflammation. Restoration of CD4+ T cells in GALT correlated with qualitative changes in SIV gag-specific CD8+ T-cell responses, with a dominance of interleukin-2-producing responses in PSI animals, while both CSI macaques and untreated SIV-infected controls were dominated by gamma interferon responses. Thus, central memory CD4+ T-cell levels and qualitative antiviral CD8+ T-cell responses, independent of viral suppression, were the immune correlates of gut mucosal immune restoration during ART.

  14. Tomato bushy stunt virus (TBSV) infecting Lycopersicon esculentum.

    Science.gov (United States)

    Hafez, El Sayed E; Saber, Ghada A; Fattouh, Faiza A

    2010-01-01

    Tomato bushy stunt virus (TBSV) was detected in tomato crop (Lycopersicon esculentum) in Egypt with characteristic mosaic leaf deformation, stunting, and bushy growth symptoms. TBSV infection was confirmed serologically by ELISA and calculated incidence was 25.5%. Basic physicochemical properties of a purified TBSV Egh isolate were identical to known properties of tombusviruses of isometric 30-nm diameter particles, 41-kDa coat protein and the genome of approximately 4800 nt. This is the first TBSV isolate reported in Egypt. Cloning and partial sequencing of the isolate showed that it is more closely related to TBSV-P and TBSV-Ch than TBSV-Nf and TBSV-S strains of the virus. However, it is distinct from the above strains and could be a new strain of the virus which further confirms the genetic diversity of tombusviruses.

  15. Homogeneity of Powassan virus populations in naturally infected Ixodes scapularis

    International Nuclear Information System (INIS)

    Brackney, Doug E.; Brown, Ivy K.; Nofchissey, Robert A.; Fitzpatrick, Kelly A.; Ebel, Gregory D.

    2010-01-01

    Powassan virus (POWV, Flaviviridae: Flavivirus) is the sole North American member of the tick-borne encephalitis complex and consists of two distinct lineages that are maintained in ecologically discrete enzootic transmission cycles. The underlying genetic mechanisms that lead to niche partitioning in arboviruses are poorly understood. Therefore, intra- and interhost genetic diversity was analyzed to determine if POWV exists as a quasispecies in nature and quantify selective pressures within and between hosts. In contrast to previous reports for West Nile virus (WNV), significant intrahost genetic diversity was not observed. However, pN (0.238) and d N /d S ratios (0.092) for interhost diversity were similar to those of WNV. Combined, these data suggest that purifying selection and/or population bottlenecks constrain quasispecies diversity within ticks. These same selective and stochastic mechanisms appear to drive minor sequence changes between ticks. Moreover, Powassan virus populations seem not to be structured as quasispecies in naturally infected adult deer ticks.

  16. Virus load in chimpanzees infected with human immunodeficiency virus type 1: effect of pre-exposure vaccination

    NARCIS (Netherlands)

    ten Haaft, P.; Cornelissen, M.; Goudsmit, J.; Koornstra, W.; Dubbes, R.; Niphuis, H.; Peeters, M.; Thiriart, C.; Bruck, C.; Heeney, J. L.

    1995-01-01

    Many reports indicate that a long-term asymptomatic state following human immunodeficiency virus type 1 (HIV-1) infection is associated with a low amount of circulating virus. To evaluate the possible effect of stabilizing a low virus load by non-sterilizing pre-exposure vaccination, a quantitative

  17. Infection cycles of large DNA viruses: emerging themes and underlying questions.

    Science.gov (United States)

    Mutsafi, Yael; Fridmann-Sirkis, Yael; Milrot, Elad; Hevroni, Liron; Minsky, Abraham

    2014-10-01

    The discovery of giant DNA viruses and the recent realization that such viruses are diverse and abundant blurred the distinction between viruses and cells. These findings elicited lively debates on the nature and origin of viruses as well as on their potential roles in the evolution of cells. The following essay is, however, concerned with new insights into fundamental structural and physical aspects of viral replication that were derived from studies conducted on large DNA viruses. Specifically, the entirely cytoplasmic replication cycles of Mimivirus and Vaccinia are discussed in light of the highly limited trafficking of large macromolecules in the crowded cytoplasm of cells. The extensive spatiotemporal order revealed by cytoplasmic viral factories is described and contended to play an important role in promoting the efficiency of these 'nuclear-like' organelles. Generation of single-layered internal membrane sheets in Mimivirus and Vaccinia, which proceeds through a novel membrane biogenesis mechanism that enables continuous supply of lipids, is highlighted as an intriguing case study of self-assembly. Mimivirus genome encapsidation was shown to occur through a portal different from the 'stargate' portal that is used for genome release. Such a 'division of labor' is proposed to enhance the efficacy of translocation processes of very large viral genomes. Finally, open questions concerning the infection cycles of giant viruses to which future studies are likely to provide novel and exciting answers are discussed. Copyright © 2014 Elsevier Inc. All rights reserved.

  18. [Reactivation of herpes zoster infection by varicella-zoster virus].

    Science.gov (United States)

    Cvjetković, D; Jovanović, J; Hrnjaković-Cvjetković, I; Brkić, S; Bogdanović, M

    1999-01-01

    There has been considerable interest in varicella-zoster virus in the middle of the twentieth century. Virus isolation in 1958 had made it possible to find out the complete DNA sequence of the varicella-zoster virus. Molecular identify of the causative agents of varicella and shingles had been proved. ETIOPATHOGENESIS AND HISTOPATHOLOGY: Varicella-zoster virus is a member of the Herpesviridae family. After primary infection which results in varicella, the virus becomes latent in the cerebral or posterior root ganglia. Some of these individuals develop shingles after several decades because of virus reactivation. It is caused by decline of cellular immune response. Circumstances such as old age, hard work, using of steroids or malignancies contribute to the appearance of shingles. Histopathological findings include degenerative changes of epithelial cells such as ballooning, multinucleated giant cells and eosinophilic intranuclear inclusions. Shingles occur sporadically, mainly among the elderly who have had varicella. There is no seasonal appearance of shingles. Individuals suffering from shingles may be sometimes contagious for susceptible children because of enormous amount of virus particles in vesicle fluid. Clinically, shingles is characterized at first by pain or discomfort in involved dermatome, usually without constitutional symptoms. Local edema and erythema appear before developing of rash. Maculopapular and vesicular rash evolves into crusts. The most commonly involved ganglia are: lumbar, thoracic, sacral posterior root ganglia, then geniculate ganglion of the VIIth cranial nerve and the trigeminal ganglion. The most common complication, postherpetic neuralgia, may last for as long as two or three weeks, sometimes even one year or more. Other complications that may be seen in shingles, but more rarely, are ocular (keratitis, iridocyclitis, secondary glaucoma, loss of sight), neurological (various motor neuropathies, encephalitis, Guillain-Barre syndrome

  19. Validation of reference genes for quantifying changes in gene expression in virus-infected tobacco.

    Science.gov (United States)

    Baek, Eseul; Yoon, Ju-Yeon; Palukaitis, Peter

    2017-10-01

    To facilitate quantification of gene expression changes in virus-infected tobacco plants, eight housekeeping genes were evaluated for their stability of expression during infection by one of three systemically-infecting viruses (cucumber mosaic virus, potato virus X, potato virus Y) or a hypersensitive-response-inducing virus (tobacco mosaic virus; TMV) limited to the inoculated leaf. Five reference-gene validation programs were used to establish the order of the most stable genes for the systemically-infecting viruses as ribosomal protein L25 > β-Tubulin > Actin, and the least stable genes Ubiquitin-conjugating enzyme (UCE) genes were EF1α > Cysteine protease > Actin, and the least stable genes were GAPDH genes, three defense responsive genes were examined to compare their relative changes in gene expression caused by each virus. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. p53 Activation following Rift Valley fever virus infection contributes to cell death and viral production.

    Directory of Open Access Journals (Sweden)

    Dana Austin

    Full Text Available Rift Valley fever virus (RVFV is an emerging viral zoonosis that is responsible for devastating outbreaks among livestock and is capable of causing potentially fatal disease in humans. Studies have shown that upon infection, certain viruses have the capability of utilizing particular cellular signaling pathways to propagate viral infection. Activation of p53 is important for the DNA damage signaling cascade, initiation of apoptosis, cell cycle arrest and transcriptional regulation of multiple genes. The current study focuses on the role of p53 signaling in RVFV infection and viral replication. These results show an up-regulation of p53 phosphorylation at several serine sites after RVFV MP-12 infection that is highly dependent on the viral protein NSs. qRT-PCR data showed a transcriptional up-regulation of several p53 targeted genes involved in cell cycle and apoptosis regulation following RVFV infection. Cell viability assays demonstrate that loss of p53 results in less RVFV induced cell death. Furthermore, decreased viral titers in p53 null cells indicate that RVFV utilizes p53 to enhance viral production. Collectively, these experiments indicate that the p53 signaling pathway is utilized during RVFV infection to induce cell death and increase viral production.

  1. Gamma interferon augments Fc gamma receptor-mediated dengue virus infection of human monocytic cells.

    OpenAIRE

    Kontny, U; Kurane, I; Ennis, F A

    1988-01-01

    It has been reported that anti-dengue antibodies at subneutralizing concentrations augment dengue virus infection of monocytic cells. This is due to the increased uptake of dengue virus in the form of virus-antibody complexes by cells via Fc gamma receptors. We analyzed the effects of recombinant human gamma interferon (rIFN-gamma) on dengue virus infection of human monocytic cells. U937 cells, a human monocytic cell line, were infected with dengue virus in the form of virus-antibody complexe...

  2. Indigenous West Nile virus infections in horses in Albania.

    Science.gov (United States)

    Berxholi, K; Ziegler, U; Rexhepi, A; Schmidt, K; Mertens, M; Korro, K; Cuko, A; Angenvoort, J; Groschup, M H

    2013-11-01

    Serum samples collected from 167 equines of 12 districts in Albania were tested for West Nile virus-specific antibodies by enzyme-linked immunosorbent assay and virus neutralization assay, using WNV lineage 1 and 2. In addition, 95 bird serum samples from Albania and 29 horse samples from Kosovo were tested in ELISA. An overall seroprevalence rate of 22% was found in horses from Albania, whereas no specific antibodies were found in the equine samples from Kosovo and the bird samples. This is the first report indicating WNV infections in animals in Albania, and the first reported seroprevalence study conducted for Kosovo. These results provide evidence for widespread infections of WNV in Albania. © 2013 Blackwell Verlag GmbH.

  3. Simian varicella virus infection of rhesus macaques recapitulates essential features of varicella zoster virus infection in humans.

    Directory of Open Access Journals (Sweden)

    Ilhem Messaoudi

    2009-11-01

    Full Text Available Simian varicella virus (SVV, the etiologic agent of naturally occurring varicella in primates, is genetically and antigenically closely related to human varicella zoster virus (VZV. Early attempts to develop a model of VZV pathogenesis and latency in nonhuman primates (NHP resulted in persistent infection. More recent models successfully produced latency; however, only a minority of monkeys became viremic and seroconverted. Thus, previous NHP models were not ideally suited to analyze the immune response to SVV during acute infection and the transition to latency. Here, we show for the first time that intrabronchial inoculation of rhesus macaques with SVV closely mimics naturally occurring varicella (chickenpox in humans. Infected monkeys developed varicella and viremia that resolved 21 days after infection. Months later, viral DNA was detected only in ganglia and not in non-ganglionic tissues. Like VZV latency in human ganglia, transcripts corresponding to SVV ORFs 21, 62, 63 and 66, but not ORF 40, were detected by RT-PCR. In addition, as described for VZV, SVV ORF 63 protein was detected in the cytoplasm of neurons in latently infected monkey ganglia by immunohistochemistry. We also present the first in depth analysis of the immune response to SVV. Infected animals produced a strong humoral and cell-mediated immune response to SVV, as assessed by immunohistology, serology and flow cytometry. Intrabronchial inoculation of rhesus macaques with SVV provides a novel model to analyze viral and immunological mechanisms of VZV latency and reactivation.

  4. Enhanced replication of herpes simplex virus type 1 in human cells

    International Nuclear Information System (INIS)

    Miller, C.S.; Smith, K.O.

    1991-01-01

    The effects of DNA-damaging agents on the replication of herpes simplex virus type 1 (HSV-1) were assessed in vitro. Monolayers of human lung fibroblast cell lines were exposed to DNA-damaging agents (methyl methanesulfonate [MMS], methyl methanethiosulfonate [MMTS], ultraviolet light [UV], or gamma radiation [GR]) at specific intervals, before or after inoculation with low levels of HSV-1. The ability of cell monolayers to support HSV-1 replication was measured by direct plaque assay and was compared with that of untreated control samples. In this system, monolayers of different cell lines infected with identical HSV-1 strains demonstrated dissimilar levels of recovery of the infectious virus. Exposure of DNA-repair-competent cell cultures to DNA-damaging agents produced time-dependent enhanced virus replication. Treatment with agent before virus inoculation significantly (p less than 0.025) increased the number of plaques by 10 to 68%, compared with untreated control cultures, while treatment with agent after virus adsorption significantly increased (p less than 0.025) the number of plaques by 7 to 15%. In a parallel series of experiments, cells deficient in DNA repair (xeroderma pigmentosum) failed to support enhanced virus replication. These results suggest that after exposure to DNA-damaging agents, fibroblasts competent in DNA repair amplify the replication of HSV-1, and that DNA-repair mechanisms that act on a variety of chromosomal lesions may be involved in the repair and biological activation of HSV-1 genomes

  5. Epstein-Barr virus infection and related hematological diseases.

    Science.gov (United States)

    Sawada, Akihisa

    2016-01-01

    Once the Epstein-Barr virus (EBV) has infected a person, it then latently infects B cells. This latent infection lasts a lifetime. However, EBV can infect T or NK cells (T/NK cells) in rare cases. Therefore, EBV causes various hematological diseases. Among these diseases, CAEBV is regarded as the most problematic because, although it is not particularly uncommon, the diagnostic tests for this disease are not covered by health insurance, a serious illness in the "non-active" periods is lacking, and the appropriate motivation for early initiation of treatment can easily be lost. However, the symptoms may suddenly change; and if the manifestations are resistant when such exacerbation occurs, CAEBC is potentially lethal. Allogeneic hematopoietic stem cell transplantation (HSCT) is the only cure. Once the diagnosis has been made, earlier treatment initiation, safer bridging to allogeneic HSCT with multi-drug chemotherapy, and then, planned HSCT can be completed more safely and thereby achieve a better outcome.

  6. Superficial herpes simplex virus wound infection following lung transplantation.

    Science.gov (United States)

    Karolak, Wojtek; Wojarski, Jacek; Zegleń, Sławomir; Ochman, Marek; Urlik, Maciej; Hudzik, Bartosz; Wozniak-Grygiel, Elzbieta; Maruszewski, Marcin

    2017-08-01

    Surgical site infections (SSIs) are infections of tissues, organs, or spaces exposed by surgeons during performance of an invasive procedure. SSIs are classified into superficial, which are limited to skin and subcutaneous tissues, and deep. The incidence of deep SSIs in lung transplant (LTx) patients is estimated at 5%. No reports have been published as to the incidence of superficial SSIs specifically in LTx patients. Common sense would dictate that the majority of superficial SSIs would be bacterial. Uncommonly, fungal SSIs may occur, and we believe that no reports exist as to the incidence of viral wound infections in LTx patients, or in any solid organ transplant patients. We report a de novo superficial wound infection with herpes simplex virus following lung transplantation, its possible source, treatment, and resolution. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  7. Neonatal herpes simplex virus infections: where are we now?

    Science.gov (United States)

    Thompson, Clara; Whitley, Richard

    2011-01-01

    Neonatal herpes simplex virus (HSV) infection continues to cause significant morbidity and mortality despite advances in diagnosis and treatment. Prior to antiviral therapy, 85% of patients with disseminated HSV disease and 50% of patients with central nervous system disease died within 1 year. The advent of antiviral therapy has dramatically improved the prognosis of neonatal HSV with initially vidarabine and subsequently acyclovir increasing the survival rate of infected neonates and improving long-term developmental outcomes. More recently, polymerase chain reaction has allowed earlier identification of HSV infection and provided a quantitative guide to treatment. Current advances in the treatment of neonatal HSV infections are looking toward the role of prolonged oral suppression therapy in reducing the incidence of recurrent disease. Of concern, however, are increasing reports of acyclovir-resistant HSV isolates in patients following prolonged therapy.

  8. Progress toward an enhanced vaccine: Eight marked attenuated viruses to porcine reproductive and respiratory disease virus.

    Science.gov (United States)

    Spear, Allyn; Wang, Feng-Xue; Kappes, Matthew A; Das, Phani B; Faaberg, Kay S

    2018-03-01

    Recombinant viruses of strain Ingelvac® PRRS porcine reproductive and respiratory syndrome virus (PRRSV) modified live virus vaccine were produced with two individual small in-frame deletions in nonstructural protein 2 (nsp2; Δ23 and Δ87) and also the same deletions supplanted with foreign tags (Δ23-V5, Δ23-FLAG, Δ23-S, Δ87-V5, Δ87-FLAG, Δ87-S). The viruses, but one (Δ87-FLAG), were stable for 10 passages and showed minimal effects on in vitro growth. Northern hybridization showed that the Δ23-tagged probe detected intracellular viral genome RNA as well as shorter RNAs that may represent heteroclite species, while the Δ87-tagged probe detected predominantly only genome length RNAs. When the tagged viruses were used to probe nsp2 protein in infected cells, perinuclear localization similar to native nsp2 was seen. Dual infection of Δ23-S and Δ87-S viruses allowed some discrimination of individual tagged nsp2 protein, facilitating future research. The mutants could potentially also be used to differentiate infected from vaccinated animals. Published by Elsevier Inc.

  9. Natural Variation in Resistance to Virus Infection in Dipteran Insects

    Directory of Open Access Journals (Sweden)

    William H. Palmer

    2018-03-01

    Full Text Available The power and ease of Drosophila genetics and the medical relevance of mosquito-transmitted viruses have made dipterans important model organisms in antiviral immunology. Studies of virus–host interactions at the molecular and population levels have illuminated determinants of resistance to virus infection. Here, we review the sources and nature of variation in antiviral immunity and virus susceptibility in model dipteran insects, specifically the fruit fly Drosophila melanogaster and vector mosquitoes of the genera Aedes and Culex. We first discuss antiviral immune mechanisms and describe the virus-specificity of these responses. In the following sections, we review genetic and microbiota-dependent variation in antiviral immunity. In the final sections, we explore less well-studied sources of variation, including abiotic factors, sexual dimorphism, infection history, and endogenous viral elements. We borrow from work on other pathogen types and non-dipteran species when it parallels or complements studies in dipterans. Understanding natural variation in virus–host interactions may lead to the identification of novel restriction factors and immune mechanisms and shed light on the molecular determinants of vector competence.

  10. Regional Aggressive Root Resorption Caused by Neuronal Virus Infection

    Directory of Open Access Journals (Sweden)

    Inger Kjær

    2012-01-01

    Full Text Available During orthodontic treatment, root resorption can occur unexplainably. No clear distinction has been made between resorption located within specific regions and resorption occurring generally in the dentition. The purpose is to present cases with idiopathic (of unknown origin root resorption occurring regionally. Two cases of female patients, 26 and 28 years old, referred with aggressive root resorption were investigated clinically and radiographically. Anamnestic information revealed severe virus diseases during childhood, meningitis in one case and whooping cough in the other. One of the patients was treated with dental implants. Virus spreading along nerve paths is a possible explanation for the unexpected resorptions. In both cases, the resorptions began cervically. The extent of the resorption processes in the dentition followed the virus infected nerve paths and the resorption process stopped when reaching regions that were innervated differently and not infected by virus. In one case, histological examination revealed multinuclear dentinoclasts. The pattern of resorption in the two cases indicates that innervation is a factor, which under normal conditions may protect the root surface against resorption. Therefore, the normal nerve pattern is important for diagnostics and for predicting the course of severe unexpected root resorption.

  11. [Epidemiology of hepatitis E virus infection in Spain].

    Science.gov (United States)

    Echevarría, José Manuel; Fogeda, Marta; Avellón, Ana

    2015-04-01

    The general features of the epidemiology and ecology of hepatitis E virus in Spain are already known after 20 years of investigations. Genotype 3 strains, mainly from sub-genotype 3f, circulated among swine livestock and certain wild mammals, and would be sporadically transmitted to humans through direct contact with the reservoirs or by consumption of foods derived from them. Bivalve shellfish contaminated by hepatitis E virus from sewage could also play a role in transmission. Although the interpretation of results from seroprevalence studies in low endemic settings is still controversial, antibody to hepatitis E virus displays an overall prevalence less than 10% among the population of Spain, increasing significantly with age. From the, approximately, 150 cases of acute hepatitis E recorded in the international literature, males older than 40 years, suffering a mild, locally acquired disease predominate. In addition, hepatitis E might be more frequent in the North of the country than in other regions. Although the disease does not usually have a great clinical relevance, the occasional finding of cases of fulminant hepatitis, and of ribavirin-resistant, chronic hepatitis E virus infections among the immunocompromised would recommend the surveillance of the infection by the public health authority and a better implementation of specific diagnostic procedures in clinical laboratories. Copyright © 2013 Elsevier España, S.L.U. y Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

  12. A Bacteriophage-Related Chimeric Marine Virus Infecting Abalone

    Science.gov (United States)

    Zhuang, Jun; Cai, Guiqin; Lin, Qiying; Wu, Zujian; Xie, Lianhui

    2010-01-01

    Marine viruses shape microbial communities with the most genetic diversity in the sea by multiple genetic exchanges and infect multiple marine organisms. Here we provide proof from experimental infection that abalone shriveling syndrome-associated virus (AbSV) can cause abalone shriveling syndrome. This malady produces histological necrosis and abnormally modified macromolecules (hemocyanin and ferritin). The AbSV genome is a 34.952-kilobase circular double-stranded DNA, containing putative genes with similarity to bacteriophages, eukaryotic viruses, bacteria and endosymbionts. Of the 28 predicted open reading frames (ORFs), eight ORF-encoded proteins have identifiable functional homologues. The 4 ORF products correspond to a predicted terminase large subunit and an endonuclease in bacteriophage, and both an integrase and an exonuclease from bacteria. The other four proteins are homologous to an endosymbiont-derived helicase, primase, single-stranded binding (SSB) protein, and thymidylate kinase, individually. Additionally, AbSV exhibits a common gene arrangement similar to the majority of bacteriophages. Unique to AbSV, the viral genome also contains genes associated with bacterial outer membrane proteins and may lack the structural protein-encoding ORFs. Genomic characterization of AbSV indicates that it may represent a transitional form of microbial evolution from viruses to bacteria. PMID:21079776

  13. A bacteriophage-related chimeric marine virus infecting abalone.

    Directory of Open Access Journals (Sweden)

    Jun Zhuang

    Full Text Available Marine viruses shape microbial communities with the most genetic diversity in the sea by multiple genetic exchanges and infect multiple marine organisms. Here we provide proof from experimental infection that abalone shriveling syndrome-associated virus (AbSV can cause abalone shriveling syndrome. This malady produces histological necrosis and abnormally modified macromolecules (hemocyanin and ferritin. The AbSV genome is a 34.952-kilobase circular double-stranded DNA, containing putative genes with similarity to bacteriophages, eukaryotic viruses, bacteria and endosymbionts. Of the 28 predicted open reading frames (ORFs, eight ORF-encoded proteins have identifiable functional homologues. The 4 ORF products correspond to a predicted terminase large subunit and an endonuclease in bacteriophage, and both an integrase and an exonuclease from bacteria. The other four proteins are homologous to an endosymbiont-derived helicase, primase, single-stranded binding (SSB protein, and thymidylate kinase, individually. Additionally, AbSV exhibits a common gene arrangement similar to the majority of bacteriophages. Unique to AbSV, the viral genome also contains genes associated with bacterial outer membrane proteins and may lack the structural protein-encoding ORFs. Genomic characterization of AbSV indicates that it may represent a transitional form of microbial evolution from viruses to bacteria.

  14. Enhanced replication of UV-damaged Simian virus 40 DNA in carcinogen-treated mammalian cells

    International Nuclear Information System (INIS)

    Maga, J.A.

    1983-01-01

    The replication of UV-damaged Simian virus 40 (SV40) in carcinogen-treated monkey cells has been studied to elucidate the mechanism of carcinogen-enhanced reactivation. Carcinogen enhanced reactivation is the observed increase in UV-irradiated virus survival in host cells treated with low doses of carcinogen compared to UV-irradiated virus survival in untreated hosts. Carcinogen treatment of monkey kidney cells with either N-acetoxy-2-acetylaminofluorene (AAAF) or UV radiation leads to an enhanced capacity to replicate UV-damaged virus during the first round of infection. To further define the mechanism leading to enhanced replication, a detailed biochemical analysis of replication intermediates in carcinogen-treated cells was performed. Several conclusions can be drawn. First enhanced replication can be observed in the first four rounds of replication after UV irradiation of viral templates. The second major finding is that the relaxed circular intermediate model proposed for the replication of UV-damaged templates in untreated cells appears valid for replication of UV-damaged templates in carcinogen-treated cells. Possible mechanisms and the supporting evidence are discussed and future experiments outlined

  15. Electron Microscopy of Ebola Virus-Infected Cells.

    Science.gov (United States)

    Noda, Takeshi

    2017-01-01

    Ebola virus (EBOV) replicates in host cells, where both viral and cellular components show morphological changes during the process of viral replication from entry to budding. These steps in the replication cycle can be studied using electron microscopy (EM), including transmission electron microscopy (TEM) and scanning electron microscopy (SEM), which is one of the most useful methods for visualizing EBOV particles and EBOV-infected cells at the ultrastructural level. This chapter describes conventional methods for EM sample preparation of cultured cells infected with EBOV.

  16. Concurrent Infection with Hepatitis C Virus and Streptococcus pneumoniae.

    Science.gov (United States)

    Marrie, Thomas J; Tyrrell, Gregory J; Majumdar, Sumit R; Eurich, Dean T

    2017-07-01

    Little is known about concurrent infection with hepatitis C virus (HCV) and Streptococcus pneumoniae, which causes invasive pneumococcal disease (IPD). We hypothesized that co-infection with HCV and S. pneumoniae would increase risk for death and complications. We captured sociodemographic and serologic data for adults with IPD in a population-based cohort study in northern Alberta, Canada, during 2000-2014. IPD patients infected with HCV were compared with IPD patients not infected<