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Sample records for panleukopenia virus fpv

  1. Case series of feline panleukopenia virus in an animal shelter.

    PubMed

    Litster, Annette; Benjanirut, Chutamas

    2014-04-01

    The aim of this study was to describe a series of confirmed and suspected cases of feline panleukopenia virus (FPV) and in-contact cats in an adoption-guarantee shelter in an FPV-endemic area by reviewing shelter records over a 10-month period (January-October 2010). Cats were divided into three groups: in-contact group - asymptomatic cats that were housed with a FPV fecal antigen (Ag)-positive cat/kitten as part of a litter group (n = 66); FPV-survivors group (FPV-infected survivors) - tested FPV fecal Ag-positive and showed clinical signs of FPV, but survived (n = 27); FPV-non-survivors group (FPV-infected non-survivors) - showed clinical signs of FPV and either tested FPV fecal Ag-positive or were housed with an Ag-positive family member, but did not survive (n = 52). Ages ranged from 3 weeks to 3 years, but most were <6 months old (in-contact group: 79%; FPV-survivors group: 70%; FPV-non-survivors group: 85%). A seasonal peak occurred over summer, but cases occurred year-round. Anorexia, dehydration, fever and diarrhea predominated in the FPV-survivors group, and death was preceded by clinical signs of circulatory shock in the FPV-non-survivors group. Housing litters of kittens with their mother was not associated with improved outcome, perhaps because in this population clinical FPV infection was relatively common in queens arriving at the shelter with susceptible litters. PMID:23873047

  2. Development of FPV140 antigen-specific ELISA differentiating fowlpox virus isolates from all other viral pathogens of avian origin.

    PubMed

    Li, G; Hong, Q; Ren, Y; Lillehoj, H S; He, C; Ren, X

    2012-10-01

    The FPV140 gene encodes an envelope protein of fowlpox virus (FPV). In this study, the FPV140 gene of FPV Chinese isolate HH2008 was cloned and the comparison of its sequence with other FPV isolates showed it to be highly conserved across all FPV isolates. A recombinant plasmid pET-FPV140 carrying FPV140 gene was constructed and transformed into Escherichia coli. The optimal expression condition for the FPV140 gene was developed and purified FPV140 recombinant protein was used to produce rabbit polyclonal antibody. An indirect ELISA using this anti-FPV140 polyclonal antibody was capable of distinguishing avian FPV isolates from other common avian pathogens such as mycoplasma gallisepticum, infectious laryngotracheitis virus, avian influenza virus, infectious bursal disease virus, and avian infectious bronchitis virus. This ELISA will serve as a useful diagnostic tool for the detection of FPV in clinical samples. PMID:22991535

  3. Canine and feline host ranges of canine parvovirus and feline panleukopenia virus: distinct host cell tropisms of each virus in vitro and in vivo.

    PubMed Central

    Truyen, U; Parrish, C R

    1992-01-01

    Canine parvovirus (CPV) emerged as an apparently new virus during the mid-1970s. The origin of CPV is unknown, but a variation from feline panleukopenia virus (FPV) or another closely related parvovirus is suspected. Here we examine the in vitro and in vivo canine and feline host ranges of CPV and FPV. Examination of three canine and six feline cell lines and mitogen-stimulated canine and feline peripheral blood lymphocytes revealed that CPV replicates in both canine and feline cells, whereas FPV replicates efficiently only in feline cells. The in vivo host ranges were unexpectedly complex and distinct from the in vitro host ranges. Inoculation of dogs with FPV revealed efficient replication in the thymus and, to some degree, in the bone marrow, as shown by virus isolation, viral DNA recovery, and Southern blotting and by strand-specific in situ hybridization. FPV replication could not be demonstrated in mesenteric lymph nodes or in the small intestine, which are important target tissues in CPV infection. Although CPV replicated well in all the feline cells tested in vitro, it did not replicate in any tissue of cats after intramuscular or intravenous inoculation. These results indicate that these viruses have complex and overlapping host ranges and that distinct tissue tropisms exist in the homologous and heterologous hosts. Images PMID:1323703

  4. DNA vaccine prime and recombinant FPV vaccine boost: an important candidate immunization strategy to control bluetongue virus type 1.

    PubMed

    Li, Junping; Yang, Tao; Xu, Qingyuan; Sun, Encheng; Feng, Yufei; Lv, Shuang; Zhang, Qin; Wang, Haixiu; Wu, Donglai

    2015-10-01

    Bluetongue virus (BTV) is the causative agent of bluetongue (BT), an important sheep disease that caused great economic loss to the sheep industry. There are 26 BTV serotypes based on the outer protein VP2. However, the serotypes BTV-1 and BTV-16 are the two most prevalent serotypes in China. Vaccination is the most effective method of preventing viral infections. Therefore, the need for an effective vaccine against BTV is urgent. In this study, DNA vaccines and recombinant fowlpox virus (rFPV) vaccines expressing VP2 alone or VP2 in combination with VP5 or co-expressing the VP2 and VP5 proteins of BTV-1 were evaluated in both mice and sheep. Several strategies were tested in mice, including DNA vaccine prime and boost, rFPV vaccine prime and boost, and DNA vaccine prime and rFPV vaccine boost. We then determined the best vaccine strategy in sheep. Our results indicated that a strategy combining a DNA vaccine prime (co-expressing VP2 and VP5) followed by an rFPV vaccine boost (co-expressing VP2 and VP5) induced a high titer of neutralizing antibodies in sheep. Therefore, our data suggest that a DNA vaccine consisting of a pCAG-(VP2+VP5) prime and an rFPV-(VP2+VP5) boost is an important candidate for the design of a novel vaccine against BTV-1. PMID:26048472

  5. 9 CFR 113.203 - Feline Panleukopenia Vaccine, Killed Virus.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...-neutralization test. Bulk or final container samples of completed product shall be tested for potency using five... susceptibility. (1) A constant virus-varying serum neutralization test in tissue culture using 100 to 300 TCID50 of virus shall be used. Cats shall be considered susceptible if there is no neutralization at a...

  6. 9 CFR 113.203 - Feline Panleukopenia Vaccine, Killed Virus.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...-neutralization test. Bulk or final container samples of completed product shall be tested for potency using five... susceptibility. (1) A constant virus-varying serum neutralization test in tissue culture using 100 to 300 TCID50 of virus shall be used. Cats shall be considered susceptible if there is no neutralization at a...

  7. 9 CFR 113.203 - Feline Panleukopenia Vaccine, Killed Virus.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...-neutralization test. Bulk or final container samples of completed product shall be tested for potency using five... susceptibility. (1) A constant virus-varying serum neutralization test in tissue culture using 100 to 300 TCID50 of virus shall be used. Cats shall be considered susceptible if there is no neutralization at a...

  8. 9 CFR 113.203 - Feline Panleukopenia Vaccine, Killed Virus.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...-neutralization test. Bulk or final container samples of completed product shall be tested for potency using five... susceptibility. (1) A constant virus-varying serum neutralization test in tissue culture using 100 to 300 TCID50 of virus shall be used. Cats shall be considered susceptible if there is no neutralization at a...

  9. 9 CFR 113.203 - Feline Panleukopenia Vaccine, Killed Virus.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... susceptible cats (four vaccinates and one control) as the test animals. Blood samples drawn from each cat... of virus shall be used. Cats shall be considered susceptible if there is no neutralization at a 1:2... dose and the cats observed each day for 14 to 21 days. (3) Serology. At the end of the...

  10. Outbreak of fatal salmonellosis in cats following use of a high-titer modified-live panleukopenia virus vaccine.

    PubMed

    Foley, J E; Orgad, U; Hirsh, D C; Poland, A; Pedersen, N C

    1999-01-01

    A 14-week-old kitten from a private cattery was examined because of an acute onset of recumbency and epistaxis 10 days after receiving a high-titer modified-live virus vaccine containing panleukopenia virus, calicivirus, and herpesvirus components. The kitten died the following day, and intestinal crypt necrosis; hepatic, splenic, and lymph node inflammation and necrosis; and pneumonia were seen at necropsy. Salmonella typhimurium was isolated from mesenteric lymph nodes and the spleen. The breeder reported that 4 other kittens had died in the previous month, each within 1 to 2 weeks after being vaccinated with the same modified-live virus vaccine. Carcasses of 3 kittens were available for examination, and Salmonella sp was isolated from mesenteric lymph nodes of all 3. Villus crypt necrosis and secondary fibrosis were also found. Three of the remaining 12 kittens in the cattery were also found to be shedding Salmonella sp in their feces. Clinical and pathologic findings in these kittens were likely attributable to salmonellosis and panleukopenia, and suggest that mild immunosuppression induced by vaccination could have facilitated development of fatal salmonellosis in subclinical carrier kittens. However, we cannot prove that vaccination actually played any role. PMID:9887942

  11. Molecular screening by polymerase chain reaction detects panleukopenia virus DNA in formalin-fixed hearts from cats with idiopathic cardiomyopathy and myocarditis.

    PubMed

    Meurs, K M; Fox, P R; Magnon, A L; Liu, S; Towbin, J A

    2000-01-01

    Viral myocarditis has been suggested as an etiology for cardiomyopathy in several mammalian species. Myocarditis and idiopathic cardiomyopathy have been reported in the domestic cat, although a viral etiology has not been demonstrated. Because of the continuing interest in the potential relationship between viral myocarditis and cardiomyopathy, we evaluated hearts from cats with spontaneous, idiopathic cardiomyopathy for viral genomic material within myocytes by polymerase chain reaction, and for the presence of myocarditis by light microscopy. Thirty-one (31) formalin-fixed hearts from domestic cats who died of idiopathic cardiomyopathy were randomly selected from pathology archives. Seventeen (17) formalin-fixed hearts from healthy cats were similarly selected as normal controls. The polymerase chain reaction (PCR) was used to evaluate myocardial tissue for the presence of viral genome from feline panleukopenia virus, herpes virus, calici virus, and corona virus. Hearts were examined using light microscopy for histologic evidence of myocarditis according to the Dallas criteria. Panleukopenia virus was identified by PCR in 10 of 31 cats with cardiomyopathy but in none of the controls. Neither cardiomyopathic or control cats tested positive by PCR for herpes virus, calici virus, and corona virus. Myocarditis was detected by histologic examination in 18 of 31 cardiomyopathic cats and in none of 17 control cats. Myocarditis and or feline panleukopenia virus genome was detected in felines with idiopathic hypertrophic, dilated, and restrictive cardiomyopathy, suggesting a possible role of viral infection and inflammation in the pathogenesis of cardiomyopathy in this species. PMID:10867362

  12. Successive deaths of a captive snow leopard (Uncia uncia) and a serval (Leptailurus serval) by infection with feline panleukopenia virus at Sapporo Maruyama Zoo.

    PubMed

    Sassa, Yukiko; Yamamoto, Hideaki; Mochizuki, Masami; Umemura, Takashi; Horiuchi, Motohiro; Ishiguro, Naotaka; Miyazawa, Takayuki

    2011-04-01

    Feline parvoviruses were isolated from frozen samples of intestines taken from a snow leopard (Uncia uncia) and a serval (Leptailurus serval) that died successively at Sapporo Maruyama Zoo in Hokkaido, Japan. Isolates possessed an antigenic epitope for both the feline panleukopenia virus (FPLV) and mink enteritis virus, identified with a hemagglutination inhibition test. Sequencing analyses of the VP2 region of the isolates revealed that the two isolates were identical and of the FPLV-type. These results suggested that FPLV was introduced from a feral cat which entered the zoo and transmitted the virus inside the zoo. PMID:21116104

  13. Snapshot of viral infections in wild carnivores reveals ubiquity of parvovirus and susceptibility of Egyptian mongoose to feline panleukopenia virus.

    PubMed

    Duarte, Margarida D; Henriques, Ana Margarida; Barros, Sílvia Carla; Fagulha, Teresa; Mendonça, Paula; Carvalho, Paulo; Monteiro, Madalena; Fevereiro, Miguel; Basto, Mafalda P; Rosalino, Luís Miguel; Barros, Tânia; Bandeira, Victor; Fonseca, Carlos; Cunha, Mónica V

    2013-01-01

    The exposure of wild carnivores to viral pathogens, with emphasis on parvovirus (CPV/FPLV), was assessed based on the molecular screening of tissue samples from 128 hunted or accidentally road-killed animals collected in Portugal from 2008 to 2011, including Egyptian mongoose (Herpestes ichneumon, n = 99), red fox (Vulpes vulpes, n = 19), stone marten (Martes foina, n = 3), common genet (Genetta genetta, n = 3) and Eurasian badger (Meles meles, n = 4). A high prevalence of parvovirus DNA (63%) was detected among all surveyed species, particularly in mongooses (58%) and red foxes (79%), along with the presence of CPV/FPLV circulating antibodies that were identified in 90% of a subset of parvovirus-DNA positive samples. Most specimens were extensively autolysed, restricting macro and microscopic investigations for lesion evaluation. Whenever possible to examine, signs of active disease were not present, supporting the hypothesis that the parvovirus vp2 gene fragments detected by real-time PCR possibly correspond to viral DNA reminiscent from previous infections. The molecular characterization of viruses, based on the analysis of the complete or partial sequence of the vp2 gene, allowed typifying three viral strains of mongoose and four red fox's as feline panleukopenia virus (FPLV) and one stone marten's as newCPV-2b type. The genetic similarity found between the FPLV viruses from free-ranging and captive wild species originated in Portugal and publicly available comparable sequences, suggests a closer genetic relatedness among FPLV circulating in Portugal. Although the clinical and epidemiological significance of infection could not be established, this study evidences that exposure of sympatric wild carnivores to parvovirus is common and geographically widespread, potentially carrying a risk to susceptible populations at the wildlife-domestic interface and to threatened species, such as the wildcat (Felis silvestris) and the critically

  14. Snapshot of Viral Infections in Wild Carnivores Reveals Ubiquity of Parvovirus and Susceptibility of Egyptian Mongoose to Feline Panleukopenia Virus

    PubMed Central

    Duarte, Margarida D.; Henriques, Ana Margarida; Barros, Sílvia Carla; Fagulha, Teresa; Mendonça, Paula; Carvalho, Paulo; Monteiro, Madalena; Fevereiro, Miguel; Basto, Mafalda P.; Rosalino, Luís Miguel; Barros, Tânia; Bandeira, Victor; Fonseca, Carlos; Cunha, Mónica V.

    2013-01-01

    The exposure of wild carnivores to viral pathogens, with emphasis on parvovirus (CPV/FPLV), was assessed based on the molecular screening of tissue samples from 128 hunted or accidentally road-killed animals collected in Portugal from 2008 to 2011, including Egyptian mongoose (Herpestes ichneumon, n = 99), red fox (Vulpes vulpes, n = 19), stone marten (Martes foina, n = 3), common genet (Genetta genetta, n = 3) and Eurasian badger (Meles meles, n = 4). A high prevalence of parvovirus DNA (63%) was detected among all surveyed species, particularly in mongooses (58%) and red foxes (79%), along with the presence of CPV/FPLV circulating antibodies that were identified in 90% of a subset of parvovirus-DNA positive samples. Most specimens were extensively autolysed, restricting macro and microscopic investigations for lesion evaluation. Whenever possible to examine, signs of active disease were not present, supporting the hypothesis that the parvovirus vp2 gene fragments detected by real-time PCR possibly correspond to viral DNA reminiscent from previous infections. The molecular characterization of viruses, based on the analysis of the complete or partial sequence of the vp2 gene, allowed typifying three viral strains of mongoose and four red fox’s as feline panleukopenia virus (FPLV) and one stone marten’s as newCPV-2b type. The genetic similarity found between the FPLV viruses from free-ranging and captive wild species originated in Portugal and publicly available comparable sequences, suggests a closer genetic relatedness among FPLV circulating in Portugal. Although the clinical and epidemiological significance of infection could not be established, this study evidences that exposure of sympatric wild carnivores to parvovirus is common and geographically widespread, potentially carrying a risk to susceptible populations at the wildlife-domestic interface and to threatened species, such as the wildcat (Felis silvestris) and the critically

  15. Vaccination against Feline Panleukopenia: implications from a field study in kittens

    PubMed Central

    2012-01-01

    Background Feline Panleukopenia (FPL) is a serious disease of cats that can be prevented by vaccination. Kittens are routinely vaccinated repeatedly during their first months of life. By this time maternally derived antibodies (MDA) can interfere with vaccination and inhibit the development of active immunity. The efficacy of primary vaccination under field conditions was questioned by frequent reports to the Paul-Ehrlich-Institut on outbreaks of FPL in vaccinated breeding catteries. We therefore initiated a field study to investigate the development of immunity in kittens during primary vaccination against FPL. 64 kittens from 16 litters were vaccinated against FPL at the age of 8, 12 and 16 weeks using three commercial polyvalent vaccines. Blood samples were taken before each vaccination and at the age of 20 weeks. Sera were tested for antibodies against Feline Panleukopenia Virus (FPV) by hemagglutination inhibition test and serum neutralisation assay in two independent diagnostic laboratories. Results There was a good correlation between the results obtained in different laboratories and with different methods. Despite triple vaccination 36.7% of the kittens did not seroconvert. Even very low titres of MDA apparently inhibited the development of active immunity. The majority of kittens displayed significant titres of MDA at 8 and 12 weeks of age; in some animals MDA were still detected at 20 weeks of age. Interestingly, the vaccines tested differed significantly in their ability to overcome low levels of maternal immunity. Conclusions In the given situation it is recommended to quantify antibodies against FPV in the serum of the queen or kittens before primary vaccination of kittens. The beginning of primary vaccination should be delayed until MDA titres have declined. Unprotected kittens that have been identified serologically should be revaccinated. PMID:22613093

  16. 9 CFR 113.304 - Feline Panleukopenia Vaccine.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... virus, each of two feline panleukopenia susceptible cats, as determined by the criteria prescribed in paragraph (c)(1) of this section, shall be injected subcutaneously with the equivalent of one cat dose each and the cats observed each day for 21 days. If either or both cats show signs of disease or...

  17. 9 CFR 113.304 - Feline Panleukopenia Vaccine.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... virus, each of two feline panleukopenia susceptible cats, as determined by the criteria prescribed in paragraph (c)(1) of this section, shall be injected subcutaneously with the equivalent of one cat dose each and the cats observed each day for 21 days. If either or both cats show signs of disease or...

  18. 9 CFR 113.304 - Feline Panleukopenia Vaccine.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... virus, each of two feline panleukopenia susceptible cats, as determined by the criteria prescribed in paragraph (c)(1) of this section, shall be injected subcutaneously with the equivalent of one cat dose each and the cats observed each day for 21 days. If either or both cats show signs of disease or...

  19. 9 CFR 113.304 - Feline Panleukopenia Vaccine.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... virus, each of two feline panleukopenia susceptible cats, as determined by the criteria prescribed in paragraph (c)(1) of this section, shall be injected subcutaneously with the equivalent of one cat dose each and the cats observed each day for 21 days. If either or both cats show signs of disease or...

  20. Antibody response to vaccines for rhinotracheitis, caliciviral disease, panleukopenia, feline leukemia, and rabies in tigers (Panthera tigris) and lions (Panthera leo).

    PubMed

    Risi, Emmanuel; Agoulon, Albert; Allaire, Franck; Le Dréan-Quénec'hdu, Sophie; Martin, Virginie; Mahl, Philippe

    2012-06-01

    This article presents the results of a study of captive tigers (Panthera tigris) and lions (Panthera leo) vaccinated with a recombinant vaccine against feline leukemia virus; an inactivated adjuvanted vaccine against rabies virus; and a multivalent modified live vaccine against feline herpesvirus, calicivirus, and panleukopenia virus. The aim of the study was to assess the immune response and safety of the vaccines and to compare the effects of the administration of single (1 ml) and double (2 ml) doses. The animals were separated into two groups and received either single or double doses of vaccines, followed by blood collection for serologic response for 400 days. No serious adverse event was observed, with the exception of abortion in one lioness, potentially caused by the incorrect use of the feline panleukopenia virus modified live vaccine. There was no significant difference between single and double doses for all vaccines. The recombinant vaccine against feline leukemia virus did not induce any serologic response. The vaccines against rabies and feline herpesvirus induced a significant immune response in the tigers and lions. The vaccine against calicivirus did not induce a significant increase in antibody titers in either tigers or lions. The vaccine against feline panleukopenia virus induced a significant immune response in tigers but not in lions. This report demonstrates the value of antibody titer determination after vaccination of nondomestic felids. PMID:22779227

  1. Characterisation of canine parvovirus strains isolated from cats with feline panleukopenia.

    PubMed

    Decaro, Nicola; Buonavoglia, Domenico; Desario, Costantina; Amorisco, Francesca; Colaianni, Maria Loredana; Parisi, Antonio; Terio, Valentina; Elia, Gabriella; Lucente, Maria Stella; Cavalli, Alessandra; Martella, Vito; Buonavoglia, Canio

    2010-10-01

    Unlike the original canine parvovirus type 2 (CPV-2), CPV-2 variants have gained the ability to replicate in vivo in cats but there is limited information on the disease patterns induced by these variants in the feline host. During 2008, two distinct cases of parvoviral infection were diagnosed in our laboratories. A CPV-2a variant was identified in a 3-month-old Persian kitten displaying clinical sign of feline panleukopenia (FPL) (acute gastroenteritis and marked leukopenia) and oral ulcerations, that died eight days after the onset of the disease. Two pups living in the same pet shop as the cat were found to shed a CPV-2a strain genetically identical to the feline virus and were likely the source of infection. Also, non-fatal infection by a CPV-2c strain occurred in a 2.5-month-old European shorthair kitten displaying non-haemorrhagic diarrhoea and normal white blood cell counts. By sequence analysis of the major capsid protein (VP2) gene, the feline CPV-2c strain showed 100% identity to a recent canine type-2c isolate. Both kittens had been administered multivalent vaccines against common feline pathogens including FPL virus. Whether and to which extent the FPL vaccines can protect cats adequately from the antigenic variants of CPV-2 should be assessed. PMID:20334885

  2. Immune responses of chickens inoculated with a recombinant fowlpox vaccine coexpressing glycoprotein B of infectious laryngotracheitis virus and chicken IL-18.

    PubMed

    Chen, Hong-Ying; Cui, Pei; Cui, Bao-An; Li, He-Ping; Jiao, Xian-Qin; Zheng, Lan-Lan; Cheng, Guo; Chao, An-Jun

    2011-11-01

    Infectious laryngotracheitis virus (ILTV) is an alphaherpesvirus that causes severe and economically significant respiratory disease in poultry worldwide. Herein, the immunogenicity of two recombinant fowlpox viruses (rFPV-gB and rFPV-gB/IL18) containing ILTV glycoprotein B (gB) and chicken interleukin-18 (IL-18) were investigated in a challenge model. One-day-old specific-pathogen-free chickens were vaccinated by wing-web puncture with the two rFPVs and challenged with the virulent ILTV CG strain. There were differences in antibody levels elicited by either rFPV-gB/IL18 or rFPV-gB as determined using ELISA. The ratios of CD4(+) to CD8(+) in chickens immunized with rFPV-gB/IL18 were higher (P < 0.05) than in those immunized with rFPV-gB, and the level of proliferative response of the T cells in the rFPV-gB/IL18-vaccinated group was higher (P < 0.05) than that in the rFPV-gB group. All chickens immunized with rFPV-gB/IL18 were protected (10/10), whereas only eight of 10 of the chickens immunized with the rFPV-gB were protected. The results showed that the protective efficacy of the rFPV-gB vaccine could be enhanced by simultaneous expression of chicken IL-18. PMID:22077232

  3. Determination of Uas Trajectory in a Known Environment from Fpv Video

    NASA Astrophysics Data System (ADS)

    Li-Chee-Ming, J.; Armenakis, C.

    2013-08-01

    This paper presents a novel self-localization method. The algorithm automatically establishes correspondence between the FPV video streamed from a UAS flying in a structured urban environment and its 3D model. The resulting camera pose provides a precise navigation solution in the densely crowded environment. Initially, Vertical Line Features are extracted from a streamed FPV video frame, as the camera is kept approximately leveled through a gimbal system. The features are then matched with Vertical Line Features extracted from a synthetic image of the 3D model. A space resection is performed to provide the EOPs for this frame. The features are tracked in the next frame, followed by an incremental triangulation. The main contribution of this paper lies in automating this process as an FPV video sequence typically consists of thousands of frames. Accuracies of the position and orientation parameters of the video camera and the validation checks of the estimated parameters are presented. Future work includes testing the method in real-time to determine latencies and reliability, and multi-directional field of view of the FPV video camera.

  4. Differential diagnosis of fowlpox and infectious laryngotracheitis viruses in chicken diphtheritic manifestations by mono and duplex real-time polymerase chain reaction.

    PubMed

    Davidson, Irit; Raibstein, Israel; Altory, Amira

    2015-01-01

    Infectious laryngotracheitis virus (ILTV) and fowlpox virus (FPV) cause diphtheritic lesions in chicken tracheas and can simultaneously infect the same bird. A differential molecular diagnostic test, the duplex real-time polymerase chain reaction, is now reported using ILTV and FPV vaccine viruses and clinical samples from chickens, either uninfected or naturally infected with ILTV or FPV, or with both viruses. The dual virus amplification by real-time polymerase chain reaction was demonstrated to behave similarly to monoplex amplification, in spite of the fact that the real-time exponential amplification plots of the vaccine viruses were more illustrative than those of the clinical samples. PMID:25317604

  5. 9 CFR 113.304 - Feline Panleukopenia Vaccine.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    .... (i) A constant virus-carrying serum neutralization test in tissue culture using 100 to 300 TCID50 of virus shall be used. (ii) Cats shall be considered susceptible if there is no neutralization at a...

  6. Ferric-Pyoverdine Recognition by Fpv Outer Membrane Proteins of Pseudomonas protegens Pf-5

    PubMed Central

    Hartney, Sierra L.; Mazurier, Sylvie; Girard, Maëva K.; Mehnaz, Samina; Davis, Edward W.; Gross, Harald; Lemanceau, Philippe

    2013-01-01

    The soil bacterium Pseudomonas protegens Pf-5 (previously called P. fluorescens Pf-5) produces two siderophores, enantio-pyochelin and a compound in the large and diverse pyoverdine family. Using high-resolution mass spectroscopy, we determined the structure of the pyoverdine produced by Pf-5. In addition to producing its own siderophores, Pf-5 also utilizes ferric complexes of some pyoverdines produced by other strains of Pseudomonas spp. as sources of iron. Previously, phylogenetic analysis of the 45 TonB-dependent outer membrane proteins in Pf-5 indicated that six are in a well-supported clade with ferric-pyoverdine receptors (Fpvs) from other Pseudomonas spp. We used a combination of phylogenetics, bioinformatics, mutagenesis, pyoverdine structural determinations, and cross-feeding bioassays to assign specific ferric-pyoverdine substrates to each of the six Fpvs of Pf-5. We identified at least one ferric-pyoverdine that was taken up by each of the six Fpvs of Pf-5. Functional redundancy of the Pf-5 Fpvs was also apparent, with some ferric-pyoverdines taken up by all mutants with a single Fpv deletion but not by a mutant having deletions in two of the Fpv-encoding genes. Finally, we demonstrated that phylogenetically related Fpvs take up ferric complexes of structurally related pyoverdines, thereby establishing structure-function relationships that can be employed in the future to predict the pyoverdine substrates of Fpvs in other Pseudomonas spp. PMID:23222724

  7. Ferric-pyoverdine recognition by Fpv outer membrane proteins of Pseudomonas protegens Pf-5.

    PubMed

    Hartney, Sierra L; Mazurier, Sylvie; Girard, Maëva K; Mehnaz, Samina; Davis, Edward W; Gross, Harald; Lemanceau, Philippe; Loper, Joyce E

    2013-02-01

    The soil bacterium Pseudomonas protegens Pf-5 (previously called P. fluorescens Pf-5) produces two siderophores, enantio-pyochelin and a compound in the large and diverse pyoverdine family. Using high-resolution mass spectroscopy, we determined the structure of the pyoverdine produced by Pf-5. In addition to producing its own siderophores, Pf-5 also utilizes ferric complexes of some pyoverdines produced by other strains of Pseudomonas spp. as sources of iron. Previously, phylogenetic analysis of the 45 TonB-dependent outer membrane proteins in Pf-5 indicated that six are in a well-supported clade with ferric-pyoverdine receptors (Fpvs) from other Pseudomonas spp. We used a combination of phylogenetics, bioinformatics, mutagenesis, pyoverdine structural determinations, and cross-feeding bioassays to assign specific ferric-pyoverdine substrates to each of the six Fpvs of Pf-5. We identified at least one ferric-pyoverdine that was taken up by each of the six Fpvs of Pf-5. Functional redundancy of the Pf-5 Fpvs was also apparent, with some ferric-pyoverdines taken up by all mutants with a single Fpv deletion but not by a mutant having deletions in two of the Fpv-encoding genes. Finally, we demonstrated that phylogenetically related Fpvs take up ferric complexes of structurally related pyoverdines, thereby establishing structure-function relationships that can be employed in the future to predict the pyoverdine substrates of Fpvs in other Pseudomonas spp. PMID:23222724

  8. The soluble pyocins S2 and S4 from Pseudomonas aeruginosa bind to the same FpvAI receptor.

    PubMed

    Elfarash, Ameer; Wei, Qing; Cornelis, Pierre

    2012-09-01

    Soluble (S-type) pyocins are Pseudomonas aeruginosa bacteriocins that kill nonimmune P. aeruginosa cells by gaining entry via a specific receptor, which, in the case of pyocin S2, is the siderophore pyoverdine receptor FpvAI, and in the case of pyocin S3, FpvAII. The nucleic acid sequence at the positions 4327697-4327359 of P. aeruginosa PAO1 genome was not annotated, but it was predicted to encode the immunity gene of the flanking pyocin S4 gene (PA3866) based on our analysis of the genome sequence. Using RT-PCR, the expression of the immunity gene was detected, confirming the existence of an immunity gene overlapping the S4 pyocin gene. The PA3866 coding for pyocin S4 and the downstream gene coding for the immunity protein were cloned and expressed in Escherichia coli and the His-tagged S4 pyocin was obtained in pure form. Forty-three P. aeruginosa strains were typed via PCR to identify their ferripyoverdine receptor gene (fpvAI-III) and were tested for their sensitivity to pyocin S4. All S4-sensitive strains had the type I ferripyoverdine receptor fpvA gene. Some S4-resistant type I fpvA-positive strains were detected, but all of them had the S4 immunity gene, and, following the deletion of the immunity gene, became S4-sensitive. The fpvAI receptor gene was deleted in a S4-sensitive strain, and, as expected, the mutant became resistant to S4. The N-terminal receptor binding domain (RBD) of pyocin S2, which also uses the FpvAI receptor to enter the cell, was cloned in the pET-15b vector, and expressed in E. coli. When the purified RBD was mixed with pyocin S4 at different ratios, an inhibition of killing was observed, indicating that S2 RBD competes with the pyocin S4 for the binding to the FpvAI receptor. The S2 RBD was also shown to enhance the expression of the pvdA pyoverdine gene, suggesting that it, like pyoverdine, works via the known siderophore-mediated signalization pathway. PMID:23170226

  9. Selectivity of pyoverdine recognition by the FpvA receptor of Pseudomonas aeruginosa from molecular dynamics simulations.

    PubMed

    Bouvier, Benjamin; Cézard, Christine; Sonnet, Pascal

    2015-07-21

    The Gram-negative bacterium Pseudomonas aeruginosa, a ubiquitous human opportunistic pathogen, has developed resistances to multiple antibiotics. It uses its primary native siderophore, pyoverdine, to scavenge the iron essential to its growth in the outside medium and transport it back into its cytoplasm. The FpvA receptor on the bacterial outer membrane recognizes and internalizes pyoverdine bearing its iron payload, but can also bind pyoverdines from other Pseudomonads or synthetic analogues. Pyoverdine derivatives could therefore be used as vectors to deliver antibiotics into the bacterium. In this study, we use molecular dynamics and free energy calculations to characterize the mechanisms and thermodynamics of the recognition of the native pyoverdines of P. aeruginosa and P. fluorescens by FpvA. Based on these results, we delineate the features that pyoverdines with high affinity for FpvA should possess. In particular, we show that (i) the dynamics and interaction of the unbound pyoverdines with water should be optimized with equal care as the interface contacts in the complex with FpvA; (ii) the C-terminal extremity of the pyoverdine chain, which appears to play no role in the bound complex, is involved in the intermediate stages of recognition; and (iii) the length and cyclicity of the pyoverdine chain can be used to fine-tune the kinetics of the recognition mechanism. PMID:26098682

  10. The Genome of Fowlpox Virus

    PubMed Central

    Afonso, C. L.; Tulman, E. R.; Lu, Z.; Zsak, L.; Kutish, G. F.; Rock, D. L.

    2000-01-01

    Here we present the genomic sequence, with analysis, of a pathogenic fowlpox virus (FPV). The 288-kbp FPV genome consists of a central coding region bounded by identical 9.5-kbp inverted terminal repeats and contains 260 open reading frames, of which 101 exhibit similarity to genes of known function. Comparison of the FPV genome with those of other chordopoxviruses (ChPVs) revealed 65 conserved gene homologues, encoding proteins involved in transcription and mRNA biogenesis, nucleotide metabolism, DNA replication and repair, protein processing, and virion structure. Comparison of the FPV genome with those of other ChPVs revealed extensive genome colinearity which is interrupted in FPV by a translocation and a major inversion, the presence of multiple and in some cases large gene families, and novel cellular homologues. Large numbers of cellular homologues together with 10 multigene families largely account for the marked size difference between the FPV genome (260 to 309 kbp) and other known ChPV genomes (178 to 191 kbp). Predicted proteins with putative functions involving immune evasion included eight natural killer cell receptors, four CC chemokines, three G-protein-coupled receptors, two β nerve growth factors, transforming growth factor β, interleukin-18-binding protein, semaphorin, and five serine proteinase inhibitors (serpins). Other potential FPV host range proteins included homologues of those involved in apoptosis (e.g., Bcl-2 protein), cell growth (e.g., epidermal growth factor domain protein), tissue tropism (e.g., ankyrin repeat-containing gene family, N1R/p28 gene family, and a T10 homologue), and avian host range (e.g., a protein present in both fowl adenovirus and Marek's disease virus). The presence of homologues of genes encoding proteins involved in steroid biogenesis (e.g., hydroxysteroid dehydrogenase), antioxidant functions (e.g., glutathione peroxidase), vesicle trafficking (e.g., two α-type soluble NSF attachment proteins), and other

  11. Detection of T- and B-cell Target Antigens of Fowlpox Virus Isolated from Backyard Chickens in India.

    PubMed

    Roy, Bithi; Joardar, Siddhartha N; Samanta, Indranil; Das, Pradip K; Alam, Sk Sahanawaz; Nandi, Sudip

    2015-06-01

    With the aim of assessing the antigenic characteristics of a circulating pool of fowlpox virus (FPV) that exists in the backyard poultry system in India, one of the field isolates generated was characterized by in vitro immunologic techniques. FPV was isolated from clinically positive fowlpox cases (n  =  10) from the Jhargram (West Midnapur district) and Kakdwip (South 24 Pargana district) areas of West Bengal State, India. Initially, FPV-specific PCR was performed for confirmation of the samples. Isolation of FPV was done using embryonated chicken eggs and the choreoallantoic membrane route. Subsequently, FPV antigen was prepared from chicken embryo fibroblast cell culture-adapted field isolate. Biologic transmission of FPV was performed in Rhode Island red chickens experimentally to assess humoral and cell-mediated immune (CMI) responses. High level of anti-FPV antibodies were observed in test birds as assessed by indirect ELISA. Seroreactive polypeptides (B-cell antigens) of FPV antigen with molecular weights of 44.5, 66.5, 75, 90.5, and 99 kDa were detected by western blot analysis. Significant increases in CMI responses were observed in inoculated chickens as assessed by lymphocyte proliferation assay, cytotoxicity assay, and T-cell immunoblotting. The predominant T-cell antigen of FPV detected had a molecular weight of 66.5 kDa. The present study revealed the antigenic characteristics of FPV that exists in backyard poultry system in West Bengal for the first time, thus exploring the rationality of designing future T- and B-cell vaccines against fowlpox. PMID:26473675

  12. Protection of chickens from Newcastle disease and infectious laryngotracheitis with a recombinant fowlpox virus co-expressing the F, HN genes of Newcastle disease virus and gB gene of infectious laryngotracheitis virus.

    PubMed

    Sun, Hui-Ling; Wang, Yun-Feng; Tong, Guang-Zhi; Zhang, Pei-Jun; Miao, De-Yuan; Zhi, Hai-Dong; Wang, Ming; Wang, Mei

    2008-03-01

    A recombinant fowlpox virus (rFPV) coexpressing the Newcastle disease virus (NDV) fusion and hemagglutinin-neuraminidase genes and infectious laryngothracheitis virus (ILTV) glycoprotein B gene was constructed. This virus was then evaluated for its ability to protect specific-pathogen-free (SPF) chickens against clinical symptoms and death after challenge by virulent NDV and ILTV. SPF chickens were grouped and vaccinated with the rFPV and commercial NDV (La Sota) and ILTV attenuated live vaccine (Nobilis ILT), respectively. After challenge with NDV 10 days postvaccination, 70% of chickens vaccinated with rFPV were protected from death, whereas 100% of the commercial NDV-vaccinated chickens were protected from death. In contrast, 100% of the unvaccinated chickens died after challenge. After challenge with ILTV, both the rFPV and commercial ILTV-vaccinated chickens were completely protected from death and 70% of chickens were protected from respiratory signs. In comparison, 100% of the unvaccinated chickens developed severe respiratory disease and 10% of chickens died. The protective efficacy was also measured by the antibody responses and isolation of challenge viruses. Results showed that this rFPV could be a potential vaccine for preventing NDV and ILTV by a single immunization. PMID:18459306

  13. Preliminary X-ray investigations of several crystal forms of the ferripyoverdine FpvA outer membrane receptor from Pseudomonas aeruginosa bound to ferripyoverdine

    SciTech Connect

    Wirth, Christophe; Hoegy, Françoise; Pattus, Franc; Cobessi, David

    2006-05-01

    The crystallization and X-ray data analysis of three crystal forms of the outer membrane pyoverdine transducer FpvA from P. aeruginosa bound to ferripyoverdine are described. The resolution of the crystals ranges from 3.15 to 2.7 Å depending on the crystal form; all were obtained in the presence of C{sub 8}E{sub 4} detergent. Ferripyoverdine transport across the outer membrane of Pseudomonas aeruginosa by the pyoverdine receptor FpvA and the transcriptional regulation of FpvA involve interactions of the FpvA N-terminal TonB box and signalling domain with proteins from the inner membrane. Several crystallization conditions of FpvA–Pvd-Fe solubilized in C{sub 8}E{sub 4} detergent were obtained and X-ray data were collected from three crystal forms. The resolution limits range from 3.15 to 2.7 Å depending on the crystal form. From preliminary analysis of the electron-density maps, the first full-length structure of an outer membrane receptor including a signalling domain should be determined.

  14. Frequent cross-species transmission of parvoviruses among diverse carnivore hosts

    USGS Publications Warehouse

    Allison, Andrew B.; Kohler, Dennis J.; Fox, Karen A.; Brown, Justin D.; Gerhold, Richard W.; Shearn-Bochsler, Valerie I.; Dubovi, Edward J.; Parrish, Colin R.; Holmes, Edward C.

    2013-01-01

    Although parvoviruses are commonly described in domestic carnivores, little is known about their biodiversity in nondomestic species. A phylogenetic analysis of VP2 gene sequences from puma, coyote, gray wolf, bobcat, raccoon, and striped skunk revealed two major groups related to either feline panleukopenia virus (“FPV-like”) or canine parvovirus (“CPV-like”). Cross-species transmission was commonplace, with multiple introductions into each host species but, with the exception of raccoons, relatively little evidence for onward transmission in nondomestic species.

  15. Frequent Cross-Species Transmission of Parvoviruses among Diverse Carnivore Hosts

    PubMed Central

    Allison, Andrew B.; Kohler, Dennis J.; Fox, Karen A.; Brown, Justin D.; Gerhold, Richard W.; Shearn-Bochsler, Valerie I.; Dubovi, Edward J.; Parrish, Colin R.

    2013-01-01

    Although parvoviruses are commonly described in domestic carnivores, little is known about their biodiversity in nondomestic species. A phylogenetic analysis of VP2 gene sequences from puma, coyote, gray wolf, bobcat, raccoon, and striped skunk revealed two major groups related to either feline panleukopenia virus (“FPV-like”) or canine parvovirus (“CPV-like”). Cross-species transmission was commonplace, with multiple introductions into each host species but, with the exception of raccoons, relatively little evidence for onward transmission in nondomestic species. PMID:23221559

  16. Frequent cross-species transmission of parvoviruses among diverse carnivore hosts.

    PubMed

    Allison, Andrew B; Kohler, Dennis J; Fox, Karen A; Brown, Justin D; Gerhold, Richard W; Shearn-Bochsler, Valerie I; Dubovi, Edward J; Parrish, Colin R; Holmes, Edward C

    2013-02-01

    Although parvoviruses are commonly described in domestic carnivores, little is known about their biodiversity in nondomestic species. A phylogenetic analysis of VP2 gene sequences from puma, coyote, gray wolf, bobcat, raccoon, and striped skunk revealed two major groups related to either feline panleukopenia virus ("FPV-like") or canine parvovirus ("CPV-like"). Cross-species transmission was commonplace, with multiple introductions into each host species but, with the exception of raccoons, relatively little evidence for onward transmission in nondomestic species. PMID:23221559

  17. Effect of complement depletion by cobra venom factor on fowlpox virus infection in chickens and chicken embryos.

    PubMed Central

    Ohta, H; Yoshikawa, Y; Kai, C; Yamanouchi, K; Taniguchi, H; Komine, K; Ishijima, Y; Okada, H

    1986-01-01

    The course of infection with an attenuated strain of fowlpox virus (FPV), which is known to induce antibody-independent activation of complement via the alternative pathway, was investigated in 1- to 3-day-old chickens and 14-day-old chicken embryos by treatment with cobra venom factor (CVF). CVF was found to inhibit complement activity transiently via the alternative pathway but not via the classical pathway. In chickens treated with CVF, virus growth in the skin was enhanced, and pock lesions tended to disseminate, leading to fatal infection in some birds. Histologically, an acute inflammation at an early stage of infection (within 3 days) was inhibited, and virus content in the pock lesion was increased. In chicken embryos with immature immune capacities, CVF treatment caused changes in pock morphology from clear pocks to diffuse ones, an increase in virus content in the pock, and inhibition of cell infiltration. Thus, FPV infection was aggravated in both CVF-treated chickens and chicken embryos. These results are discussed in relation to roles of complement in the elimination of virus at an early stage of FPV infection. Images PMID:3003397

  18. Adjuvant activity of chicken interleukin-12 co-administered with infectious bursal disease virus recombinant VP2 antigen in chickens.

    PubMed

    Su, Bor Sheu; Chiu, Hua Hsien; Lin, Cheng Chung; Shien, Jui Hung; Yin, Hsien Sheng; Lee, Long Huw

    2011-02-15

    A recombinant fowlpox virus (rFPV/VP2) expressing infectious bursal diseases virus (IBDV) VP2 gene has been constructed. After purification and identification of rFPV/VP2, the adjuvant activity of the recombinant chicken IL-12 (rchIL-12), synthesized by our previous construct of rFPV/chIL-12, in rFPV/VP2-expressed rVP2 antigen was assessed in one-week-old specific-pathogen free chickens. The results indicated that rchIL-12 alone or rchIL-12 plus mineral oil (MO) co-administered with rVP2 antigen significantly enhanced the production of serum neutralization (SN) antibody against IBDV, compared to those with MO alone. The SN titers in groups receiving rVP2 antigen with MO alone were more inconsistent after vaccination. On the other hand, rchIL-12 significantly stimulated IFN-γ production in serum and in splenocyte cultured supernatant, suggesting that rchIL-12 alone or plus MO significantly induced a cell-mediated immune response. Finally, bursal lesion protection from very virulent IBDV (vvIBDV) challenge in chickens receiving rVP2 antigen with rchIL-12 alone or plus MO was much more effective than that with MO alone at two weeks after boosting. Taken together, rchIL-12 alone augmented in vivo the induction of a primary and also a secondary SN antibody production and a cell-mediated immunity against IBDV rVP2 antigen, which conferred the enhancement of bursal lesion protective efficacy from vvIBDV challenge. These data indicated that a potential for chIL-12 as immunoadjuvant for chicken vaccine development such as IBDV rVP2 antigen. PMID:21035196

  19. Viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lytic bacteriophages, viruses which infect and lyse bacterial cells, can provide a natural method to reduce bacterial pathogens on produce commodities. The use of multi-phage cocktails is most likely to be effective against bacterial pathogens on produce commodities, and minimize the development of...

  20. Diseases associated with spontaneous feline leukemia virus (FeLV) infection in cats.

    PubMed

    Reinacher, M

    1989-05-01

    More than 2000 cats sent for necropsy in order to provide a diagnosis were investigated immunohistologically using paraffin sections for the presence of a persistent infection with feline leukemia virus (FeLV). The spectrum of neoplastic and non-neoplastic diseases associated significantly with FeLV infection was determined statistically. Three-quarters of the cats with persistent FeLV infections died of non-neoplastic diseases and about 23% died of tumors, nearly exclusively those of the leukemia/lymphoma disease complex. A strong association with liver degeneration, icterus and a FeLV-associated enteritis was found in addition to the known association with non-neoplastic diseases and conditions such as anemia, bacterial secondary infections and respiratory tract inflammations due to the immunosuppressive effect of FeLV, hemorrhages and feline infectious peritonitis. Surprisingly, diseases and conditions like feline infectious panleukopenia, enteritis (of other types than FeLV-associated enteritis and feline infectious panleukopenia), glomerulonephritis, uremia and hemorrhagic cystitis were not associated with persistent FeLV infection. Another unexpected finding was that most pathogenic infectious agents demonstrated in the cats were not FeLV-associated either. Thus, immunosuppression due to FeLV infection seems to make the animals susceptible to certain pathogenic infectious agents, but not to the majority. PMID:2549696

  1. Frequency and significance of feline leukemia virus infection in necropsied cats.

    PubMed

    Reinacher, M; Theilen, G

    1987-06-01

    Feline leukemia virus (FeLV) infection was diagnosed immunohistologically on paraffin-embedded tissues obtained from 1,095 necropsied cats. Significant association of FeLV infection was demonstrated by chi 2 and Fisher's tests with various conditions and diseases (ie, anemia, tumors of the leukemia/lymphoma complex, feline infectious peritonitis, bacterial infections, emaciation, FeLV-associated enteritis, lymphatic hyperplasia, and hemorrhage). Unexpected findings associated with FeLV infection were icterus, several types of hepatitis, and liver degeneration. A negative association with FeLV infection was found for most parasitic and viral infections, including feline panleukopenia. Neither positive nor negative associations were established for FeLV infection and most forms of nephritis, including severe glomerulonephritis. Feline leukemia virus-infected cats were significantly (Kruskal-Wallis test) older than were FeLV-negative cats with the same nonneoplastic FeLV-associated diseases. PMID:3037951

  2. Protection induced by commercially available live-attenuated and recombinant viral vector vaccines against infectious laryngotracheitis virus in broiler chickens.

    PubMed

    Vagnozzi, Ariel; Zavala, Guillermo; Riblet, Sylva M; Mundt, Alice; García, Maricarmen

    2012-01-01

    Viral vector vaccines using fowl poxvirus (FPV) and herpesvirus of turkey (HVT) as vectors and carrying infectious laryngotracheitis virus (ILTV) genes are commercially available to the poultry industry in the USA. Different sectors of the broiler industry have used these vaccines in ovo or subcutaneously, achieving variable results. The objective of the present study was to determine the efficacy of protection induced by viral vector vaccines as compared with live-attenuated ILTV vaccines. The HVT-LT vaccine was more effective than the FPV-LT vaccine in mitigating the disease and reducing levels of challenge virus when applied in ovo or subcutaneously, particularly when the challenge was performed at 57 days rather than 35 days of age. While the FPV-LT vaccine mitigated clinical signs more effectively when administered subcutaneously than in ovo, it did not reduce the concentration of challenge virus in the trachea by either application route. Detection of antibodies against ILTV glycoproteins expressed by the viral vectors was a useful criterion to assess the immunogenicity of the vectors. The presence of glycoprotein I antibodies detected pre-challenge and post challenge in chickens vaccinated with HVT-LT indicated that the vaccine induced a robust antibody response, which was paralleled by significant reduction of clinical signs. The chicken embryo origin vaccine provided optimal protection by significantly mitigating the disease and reducing the challenge virus in chickens vaccinated via eye drop. The viral vector vaccines, applied in ovo and subcutaneously, provided partial protection, reducing to some degree clinical signs, and challenge VIRUS replication in the trachea. PMID:22845318

  3. Ocelots on Barro Colorado Island Are Infected with Feline Immunodeficiency Virus but Not Other Common Feline and Canine Viruses

    PubMed Central

    Franklin, Samuel P.; Kays, Roland W.; Moreno, Ricardo; TerWee, Julie A.; Troyer, Jennifer L.; VandeWoude, Sue

    2011-01-01

    Transmission of pathogens from domestic animals to wildlife populations (spill-over) has precipitated local wildlife extinctions in multiple geographic locations. Identifying such events before they cause population declines requires differentiating spillover from endemic disease, a challenge complicated by a lack of baseline data from wildlife populations that are isolated from domestic animals. We tested sera collected from 12 ocelots (Leopardus pardalis) native to Barro Colorado Island, Panama, which is free of domestic animals, for antibodies to feline herpes virus, feline calicivirus, feline corona virus, feline panleukopenia virus, canine distemper virus, and feline immunodeficiency virus (FIV), typically a species-specific infection. Samples also were tested for feline leukemia virus antigens. Positive tests results were only observed for FIV; 50% of the ocelots were positive. We hypothesize that isolation of this population has prevented introduction of pathogens typically attributed to contact with domestic animals. The high density of ocelots on Barro Colorado Island may contribute to a high prevalence of FIV infection, as would be expected with increased contact rates among conspecifics in a geographically restricted population. PMID:18689668

  4. Ocelots on Barro Colorado Island are infected with feline immunodeficiency virus but not other common feline and canine viruses.

    PubMed

    Franklin, Samuel P; Kays, Roland W; Moreno, Ricardo; TerWee, Julie A; Troyer, Jennifer L; VandeWoude, Sue

    2008-07-01

    Transmission of pathogens from domestic animals to wildlife populations (spill-over) has precipitated local wildlife extinctions in multiple geographic locations. Identifying such events before they cause population declines requires differentiating spillover from endemic disease, a challenge complicated by a lack of baseline data from wildlife populations that are isolated from domestic animals. We tested sera collected from 12 ocelots (Leopardus pardalis) native to Barro Colorado Island, Panama, which is free of domestic animals, for antibodies to feline herpes virus, feline calicivirus, feline corona virus, feline panleukopenia virus, canine distemper virus, and feline immunodeficiency virus (FIV), typically a species-specific infection. Samples also were tested for feline leukemia virus antigens. Positive tests results were only observed for FIV; 50% of the ocelots were positive. We hypothesize that isolation of this population has prevented introduction of pathogens typically attributed to contact with domestic animals. The high density of ocelots on Barro Colorado Island may contribute to a high prevalence of FIV infection, as would be expected with increased contact rates among conspecifics in a geographically restricted population. PMID:18689668

  5. Canine and feline parvoviruses preferentially recognize the non-human cell surface sialic acid N-glycolylneuraminic acid.

    PubMed

    Löfling, Jonas; Lyi, Sangbom Michael; Parrish, Colin R; Varki, Ajit

    2013-05-25

    Feline panleukopenia virus (FPV) is a pathogen whose canine-adapted form (canine parvovirus (CPV)) emerged in 1978. These viruses infect by binding host transferrin receptor type-1 (TfR), but also hemagglutinate erythrocytes. We show that hemagglutination involves selective recognition of the non-human sialic acid N-glycolylneuraminic acid (Neu5Gc) but not N-acetylneuraminic acid (Neu5Ac), which differs by only one oxygen atom from Neu5Gc. Overexpression of α2-6 sialyltransferase did not change binding, indicating that both α2-3 and α2-6 linkages are recognized. However, Neu5Gc expression on target cells did not enhance CPV or FPV infection in vitro. Thus, the conserved Neu5Gc-binding preference of these viruses likely plays a role in the natural history of the virus in vivo. Further studies must clarify relationships between virus infection and host Neu5Gc expression. As a first step, we show that transcripts of CMAH (which generates Neu5Gc from Neu5Ac) are at very low levels in Western dog breed cells. PMID:23497940

  6. Development of an antigen-capture ELISA for the detection of avian leukosis virus p27 antigen.

    PubMed

    Yun, Bingling; Li, Delong; Zhu, Haibo; Liu, Wen; Qin, Liting; Liu, Zaisi; Wu, Guan; Wang, Yongqiang; Qi, Xiaole; Gao, Honglei; Wang, Xiaomei; Gao, Yulong

    2013-02-01

    An antigen-capture enzyme-linked immunosorbent assay (AC-ELISA) employing monoclonal and polyclonal antibodies against p27 was developed for the detection of the avian leukosis virus (ALV). The specificity of the optimized AC-ELISA was evaluated using avian leukosis virus subgroup J (ALV-J), avian leukosis virus subgroup A (ALV-A), avian leukosis virus subgroup B (ALV-B), avian infectious bronchitis virus (IBV), Marek's disease virus (MDV), avian infectious laryngotracheitis virus (ILTV), Fowlpox virus (FPV), infectious bursal disease virus (IBDV), Newcastle disease virus (NDV), avian reovirus (ARV), reticuloendotheliosis virus (REV), avian influenza virus (AIV) and Escherichia coli. The only specimens that yielded a strong signal were ALV-J, ALV-A and ALV-B, indicating that this assay is suitable for the detection of ALV. The limit of detection of this assay was 1.25 ng/ml of rp27 protein and 10(1.79)TCID(50) units of HLJ09MDJ-1 (ALV-J). Moreover, this AC-ELISA can detect ALV in cloacal swabs of chickens experimentally infected as early as 12 days post-infection. The AC-ELISA detected the virus in the albumin and cloacal swabs of naturally infected chickens, and the results were confirmed by PCR, indicating that the AC-ELISA was a suitable method for the detection of ALV. This test is rapid and sensitive and could be convenient for epidemiological studies and eradication programs. PMID:23201286

  7. Newcastle Disease Virus (NDV) Recombinants Expressing Infectious Laryngotracheitis Virus (ILTV) Glycoproteins gB and gD Protect Chickens against ILTV and NDV Challenges

    PubMed Central

    Zhao, Wei; Spatz, Stephen; Zhang, Zhenyu; Wen, Guoyuan; Garcia, Maricarmen; Zsak, Laszlo

    2014-01-01

    ABSTRACT Infectious laryngotracheitis (ILT) is a highly contagious acute respiratory disease of chickens caused by infectious laryngotracheitis virus (ILTV). The disease is controlled mainly through biosecurity and vaccination with live attenuated strains of ILTV and vectored vaccines based on turkey herpesvirus (HVT) and fowlpox virus (FPV). The current live attenuated vaccines (chicken embryo origin [CEO] and tissue culture origin [TCO]), although effective, can regain virulence, whereas HVT- and FPV-vectored ILTV vaccines are less efficacious than live attenuated vaccines. Therefore, there is a pressing need to develop safer and more efficacious ILTV vaccines. In the present study, we generated Newcastle disease virus (NDV) recombinants, based on the LaSota vaccine strain, expressing glycoproteins B (gB) and D (gD) of ILTV using reverse genetics technology. These recombinant viruses, rLS/ILTV-gB and rLS/ILTV-gD, were slightly attenuated in vivo yet retained growth dynamics, stability, and virus titers in vitro that were similar to those of the parental LaSota virus. Expression of ILTV gB and gD proteins in the recombinant virus-infected cells was detected by immunofluorescence assay. Vaccination of specific-pathogen-free chickens with these recombinant viruses conferred significant protection against virulent ILTV and velogenic NDV challenges. Immunization of commercial broilers with rLS/ILTV-gB provided a level of protection against clinical disease similar to that provided by the live attenuated commercial vaccines, with no decrease in body weight gains. The results of the study suggested that the rLS/ILTV-gB and -gD viruses are safe, stable, and effective bivalent vaccines that can be mass administered via aerosol or drinking water to large chicken populations. IMPORTANCE This paper describes the development and evaluation of novel bivalent vaccines against chicken infectious laryngotracheitis (ILT) and Newcastle disease (ND), two of the most economically

  8. Porcine parvovirus: DNA sequence and genome organization.

    PubMed

    Ranz, A I; Manclús, J J; Díaz-Aroca, E; Casal, J I

    1989-10-01

    We have determined the nucleotide sequence of an almost full-length clone of porcine parvovirus (PPV). The sequence is 4973 nucleotides (nt) long. The 3' end of virion DNA shows a Y-shaped configuration homologous to rodent parvoviruses. The 5' end of virion DNA shows a repetition of 127 nt at the carboxy terminus of the capsid proteins. The overall organization of the PPV genome is similar to those of other autonomous parvoviruses. There are two large open reading frames (ORFs) that almost entirely cover the genome, both located in the same frame of the complementary strand. The left ORF encodes the non-structural protein NS1 and the right ORF encodes the capsid proteins (VP1, VP2 and VP3). Promoter analysis, location of splicing sites and putative amino acid sequences for the viral proteins show a high homology of PPV with feline panleukopenia virus and canine parvoviruses (FPV and CPV) and rodent parvovirus. Therefore we conclude that PPV is related to the Kilham rat virus (KRV) group of autonomous parvoviruses formed by KRV, minute virus of mice, Lu III, H-1, FPV and CPV. PMID:2794971

  9. Serosurvey of viral infections in free-ranging Namibian cheetahs (Acinonyx jubatus).

    PubMed

    Munson, Linda; Marker, Laurie; Dubovi, Edward; Spencer, Jennifer A; Evermann, James F; O'Brien, Stephen J

    2004-01-01

    Cheetahs (Acinonyx jubatus) in captivity have unusually high morbidity and mortality from infectious diseases, a trait that could be an outcome of population homogeneity or the immunomodulating effects of chronic stress. Free-ranging Namibian cheetahs share ancestry with captive cheetahs, but their susceptibility to infectious diseases has not been investigated. The largest remaining population of free-ranging cheetahs resides on Namibian farmlands, where they share habitat with domestic dogs and cats known to carry viruses that affect cheetah health. To assess the extent to which free-ranging cheetahs are exposed to feline and canine viruses, sera from 81 free-ranging cheetahs sampled between 1992 and 1998 were evaluated for antibodies against canine distemper virus (CDV), feline coronavirus (feline infectious peritonitis virus; FCoV/ FIPV), feline herpesvirus 1 (FHV1), feline panleukopenia virus (FPV), feline immunodeficiency virus (FIV), and feline calicivirus (FCV) and for feline leukemia virus (FeLV) antigens. Antibodies against CDV, FCoV/FIPV, FHV1, FPV, and FCV were detected in 24, 29, 12, 48, and 65% of the free-ranging population, respectively, although no evidence of viral disease was present in any animal at the time of sample collection. Neither FIV antibodies nor FeLV antigens were present in any free-ranging cheetah tested. Temporal variation in FCoV/FIPV seroprevalence during the study period suggested that this virus is not endemic in the free-ranging population. Antibodies against CDV were detected in cheetahs of all ages sampled between 1995 and 1998, suggesting the occurrence of an epidemic in Namibia during the time when CDV swept through other parts of sub-Saharan Africa. This evidence in free-ranging Namibian cheetahs of exposure to viruses that cause severe disease in captive cheetahs should direct future guidelines for translocations, including quarantine of seropositive cheetahs and preventing contact between cheetahs and domestic pets

  10. [Abortive myxovirus infection in Ehrlich's ascitic carcinoma cells. Further study of the nature of the virus-specific structures produced by heterokaryons].

    PubMed

    Asadullaev, T A; Shekhtman, A B; Lur'e, L M; Bukrinskaia, A G

    1977-01-01

    Fowl plague virus-infected cells of Ehrlich ascitic carcinoma produce a noninfectious virus which is defective in fragility of its membranes. An attempt has been made to produce nondefective virus by fusion of infected Ehrlich cells with permissive cells: infected and non-infected chicken fibroblasts. The fusion of FPV-infected and 3H-uridine labeled Ehrlich ascitic carcinoma cells with infected unlabeled chicken fibroblasts using inactivated Sendai virus resulted in production of two types of labeled virus particles: with a buoyant density in cesium chloride gradient of 1.29 g/cm3 characteristic of particles produced by infected Ehrlich cells and buoyant density 1.22 g/cm3 typical of standard influenza virus. Both types of particles has infectious activity which was greater in the virus with the density of 1.22 g/cm3. However, particles with the density of 1.22 g/cm3 are not found upon the fusion of infected Ehrlich cells with uninfected chicken fibroblasts, with chicken fibroblasts early after infection, or with chicken fibroblasts treated with actinomycin D before infection. Infected chicken fibroblasts in hybrids were shown not to use the radioactive pool of Ehrlich cells and, accordingly, the virus with the density of 1.22 g/cm3 if formed from components pre-existing in Ehrlich cells. It is suggested that the standard virus buds on the areas of membranes of permissive cells which are parts of the hybrids. PMID:200012

  11. Canine and feline parvoviruses preferentially recognize the non-human cell surface sialic acid N-glycolylneuraminic acid

    SciTech Connect

    Löfling, Jonas; Michael Lyi, Sangbom; Parrish, Colin R.; Varki, Ajit

    2013-05-25

    Feline panleukopenia virus (FPV) is a pathogen whose canine-adapted form (canine parvovirus (CPV)) emerged in 1978. These viruses infect by binding host transferrin receptor type-1 (TfR), but also hemagglutinate erythrocytes. We show that hemagglutination involves selective recognition of the non-human sialic acid N-glycolylneuraminic acid (Neu5Gc) but not N-acetylneuraminic acid (Neu5Ac), which differs by only one oxygen atom from Neu5Gc. Overexpression of α2-6 sialyltransferase did not change binding, indicating that both α2-3 and α2-6 linkages are recognized. However, Neu5Gc expression on target cells did not enhance CPV or FPV infection in vitro. Thus, the conserved Neu5Gc-binding preference of these viruses likely plays a role in the natural history of the virus in vivo. Further studies must clarify relationships between virus infection and host Neu5Gc expression. As a first step, we show that transcripts of CMAH (which generates Neu5Gc from Neu5Ac) are at very low levels in Western dog breed cells. - Highlights: ► Feline and canine parvoviruses recognize Neu5Gc but not Neu5Ac, which differ by one oxygen atom. ► The underlying linkage of these sialic acids does not affect recognition. ► Induced Neu5Gc expression on target cells that normally express Neu5Ac did not enhance infection. ► Thus, the conserved binding preference plays an important yet unknown role in in vivo infections. ► Population and breed variations in Neu5Gc expression occur, likely by regulating the gene CMAH.

  12. Emergence of reticuloendotheliosis virus in pigeons in Guangdong Province, Southern China.

    PubMed

    Zhai, Shao-Lun; Chen, Sheng-Nan; Lin, Tao; Wen, Xiao-Hui; Wei, Wen-Kang; Lv, Dian-Hong; Chen, Rui-Ai

    2016-07-01

    Reticuloendotheliosis virus (REV), an important immunosuppressive pathogen, has many hosts, including chickens, ducks, geese, turkeys, and wild birds. Clinically, REV may lead to increased susceptibility to other pathogens, resulting in serious tissue damage (especially tumors) and the death of its host. In this study, we encountered a disease outbreak resulting in a large number of deaths of pigeons in Guangdong Province, Southern China. Histopathological analysis revealed apparent tumor-like lesions in multiple organs of pigeons. PCR assays for detection of tumor-associated pathogens (REV, avian leukosis virus, and Marek's disease virus) in poultry revealed the presence of REV sequences only. Moreover, fowlpox virus (FPV) with an insertion of REV long terminal repeat (LTR) sequences was also considered, but it was excluded using a specific PCR assay. To gain more genetic information, two full-length REV genome sequences were determined and found to have the highest nucleotide sequence similarity (99.9 %) and the closest genetic relationship to a vaccine strain (MD-2) and had a more distant genetic relationship (94.3 %) to a duck-origin strain (ATCC-VR775). To confirm the presence of REVs in pigeons, specific-pathogen-free (SPF) chickens and healthy pigeons were inoculated with microfiltered tumor tissue homogenates and were found to be susceptible to infection with REV. To our knowledge, this is the first report of REV in pigeons, and the data suggest that pigeons may be the natural host of REV. PMID:27120185

  13. Effect of high-dose ciclosporin on the immune response to primary and booster vaccination in immunocompetent cats.

    PubMed

    Roberts, Elizabeth S; VanLare, Karen A; Roycroft, Linda M; King, Stephen

    2015-02-01

    Ciclosporin (Atopica oral solution for cats 100 mg/ml; Novartis Animal Health) was recently approved for use in cats with feline hypersensitivity dermatitis. The immunosuppressant effect of ciclosporin on the ability of cats to mount an immune response following vaccination was determined. Thirty-two healthy, immunocompetent adult cats (16 cats/group) were treated with either ciclosporin for 56 days at a dose of 24 mg/kg once daily or sham dosed. Prior to treatment, cats had an adequate antibody response to primary vaccination against feline calicivirus (FCV), feline herpesvirus-1 (FHV-1), feline panleukopenia virus (FPV), feline leukemia virus (FeLV) and rabies. Booster vaccination or novel vaccination with feline immunodeficiency virus (FIV) was administered 28 days after initiation of treatment with ciclosporin. There were no differences between the ciclosporin-treated and control cats for FCV and FPV antibody titers following booster vaccination. There were delays/reductions in antibody response to FHV-1, FeLV and rabies in treated cats; however, adequate protection was achieved in response to all booster vaccinations. Following primary vaccination with FIV, control cats showed a response, but treated cats showed no antibody production. Adverse events commonly associated with ciclosporin treatment, including diarrhea/loose stool, vomiting, salivation and regurgitation, were reported. In adult cats treated with 24 mg/kg/day of ciclosporin (more than three times the therapeutic dose), vaccine titer levels were adequate for protection following booster vaccination. In contrast, treated cats failed to mount a humoral response to a novel (FIV) vaccination, suggesting that memory B-cell immune responses remain intact during repeated high-dose ciclosporin administration in cats, but that primary immune responses are impaired. PMID:24820998

  14. [New betulin derivatives in combination with rimantadine for inhibition of influenza virus reproduction].

    PubMed

    Savinova, O V; Pavlova, N I; Boreko, E I

    2009-01-01

    The preliminary studies mainly revealed comparable inhibition activities of 3-oxime of betulonic acid, 3beta-O-acetyl-28-O-hemiphthalate of betulin and 3,28-dioxime of betulin against reproduction of influenza viruses A (H1N1), A (H7N1), A (H3N2) and B, as well as against the strains of influenza virus A (H1N1) with intrinsic resistance to rimantadine and A (H7N1) with acquired resistance to the drug. The level of the activity depended on the system used for the virus reproduction. The highest level was observed under conditions providing higher permissibivity, i.e. in the chick embryo fibroblast cell culture for A (H7N1) and in fragments of chick embryo chorioallantoic membranes (for all the viruses). In the experiments with virus A/FPV/Rostock/34 (H7N1) in the chick embryo fibroblast cell culture the average effective concentrations (EC50) of the triterpene compounds were 10.4-17.5 mcM in comparison to EC50 of rimantadine (0.014 mcM). The use of every of the compounds in combination with rimantadine resulted in a 2-16 times decrease of their EC50 and correction of the concentration-effect relation of rimantadine. However, when rimantadine was used alone within the higher range of the nontoxic concentrations (11.6-57.6 mcM). its antiviral properties were significantly less pronounced. As a result the virus titer difference in comparison to the control within the above range of the rimantadine concentrations increased from < 1 to > 2.35 Ig PPU/ml and the relations of the maximal tolerance concentrations of the compounds to their EC50 increased 1.7-15.9 times. PMID:20052912

  15. Characterization of the stage(s) in the virus replication cycle at which the host-cell specificity of the feline parvovirus subgroup is regulated in canine cells.

    PubMed

    Horiuchi, M; Ishiguro, N; Goto, H; Shinagawa, M

    1992-08-01

    Feline panleukopenia virus (FPLV), mink enteritis virus (MEV), and canine parvovirus (CPV) are classified as a host-range variants. They show different host-range specificity in vivo and host-cell specificity in vitro. For instance, FPLV and MEV cannot grow or can grow only inefficiently in canine cell lines such as MDCK and the canine fibroma cell line A72. Here we have studied the mechanism(s) by which the different cell tropism is mediated in vitro. When FPLV or MEV was inoculated to A72 cells, viral DNA replicated slightly, few viral-antigen-positive cells were detected, and the culture fluid contained the threshold level of infectivity. On the other hand, when an infectious molecular clone of MEV (pMEV) was introduced into A72 cells, viral DNA replicated efficiently, and the culture fluid of pMEV-transfected cells contained much higher infectivities than that of MEV-infected cells. In spite of the restrictive growth in A72 cells, MEV could bind to A72 cells as efficiently as CPV. No detectable viral RNA was produced in MEV-infected A72 cells. In contrast, efficient viral transcription occurred in pMEV-transfected A72 cells. These results suggest that the restrictive infections of MEV and FPLV in A72 cells are not mediated by the attachment of the virus to the cells or by the events occurring after the viral transcription. It appears to be caused by the stage(s) in the virus replication cycle, which exists between a postadsorptional step required for virus penetration and the initiation of viral transcription. PMID:1322591

  16. Host-Specific Parvovirus Evolution in Nature Is Recapitulated by In Vitro Adaptation to Different Carnivore Species

    PubMed Central

    Allison, Andrew B.; Kohler, Dennis J.; Ortega, Alicia; Hoover, Elizabeth A.; Grove, Daniel M.; Holmes, Edward C.; Parrish, Colin R.

    2014-01-01

    Canine parvovirus (CPV) emerged as a new pandemic pathogen of dogs in the 1970s and is closely related to feline panleukopenia virus (FPV), a parvovirus of cats and related carnivores. Although both viruses have wide host ranges, analysis of viral sequences recovered from different wild carnivore species, as shown here, demonstrated that >95% were derived from CPV-like viruses, suggesting that CPV is dominant in sylvatic cycles. Many viral sequences showed host-specific mutations in their capsid proteins, which were often close to sites known to control binding to the transferrin receptor (TfR), the host receptor for these carnivore parvoviruses, and which exhibited frequent parallel evolution. To further examine the process of host adaptation, we passaged parvoviruses with alternative backgrounds in cells from different carnivore hosts. Specific mutations were selected in several viruses and these differed depending on both the background of the virus and the host cells in which they were passaged. Strikingly, these in vitro mutations recapitulated many specific changes seen in viruses from natural populations, strongly suggesting they are host adaptive, and which were shown to result in fitness advantages over their parental virus. Comparison of the sequences of the transferrin receptors of the different carnivore species demonstrated that many mutations occurred in and around the apical domain where the virus binds, indicating that viral variants were likely selected through their fit to receptor structures. Some of the viruses accumulated high levels of variation upon passage in alternative hosts, while others could infect multiple different hosts with no or only a few additional mutations. Overall, these studies demonstrate that the evolutionary history of a virus, including how long it has been circulating and in which hosts, as well as its phylogenetic background, has a profound effect on determining viral host range. PMID:25375184

  17. Host-specific parvovirus evolution in nature is recapitulated by in vitro adaptation to different carnivore species.

    PubMed

    Allison, Andrew B; Kohler, Dennis J; Ortega, Alicia; Hoover, Elizabeth A; Grove, Daniel M; Holmes, Edward C; Parrish, Colin R

    2014-11-01

    Canine parvovirus (CPV) emerged as a new pandemic pathogen of dogs in the 1970s and is closely related to feline panleukopenia virus (FPV), a parvovirus of cats and related carnivores. Although both viruses have wide host ranges, analysis of viral sequences recovered from different wild carnivore species, as shown here, demonstrated that>95% were derived from CPV-like viruses, suggesting that CPV is dominant in sylvatic cycles. Many viral sequences showed host-specific mutations in their capsid proteins, which were often close to sites known to control binding to the transferrin receptor (TfR), the host receptor for these carnivore parvoviruses, and which exhibited frequent parallel evolution. To further examine the process of host adaptation, we passaged parvoviruses with alternative backgrounds in cells from different carnivore hosts. Specific mutations were selected in several viruses and these differed depending on both the background of the virus and the host cells in which they were passaged. Strikingly, these in vitro mutations recapitulated many specific changes seen in viruses from natural populations, strongly suggesting they are host adaptive, and which were shown to result in fitness advantages over their parental virus. Comparison of the sequences of the transferrin receptors of the different carnivore species demonstrated that many mutations occurred in and around the apical domain where the virus binds, indicating that viral variants were likely selected through their fit to receptor structures. Some of the viruses accumulated high levels of variation upon passage in alternative hosts, while others could infect multiple different hosts with no or only a few additional mutations. Overall, these studies demonstrate that the evolutionary history of a virus, including how long it has been circulating and in which hosts, as well as its phylogenetic background, has a profound effect on determining viral host range. PMID:25375184

  18. ECHO virus

    MedlinePlus

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

  19. An insulated isothermal PCR method on a field-deployable device for rapid and sensitive detection of canine parvovirus type 2 at points of need.

    PubMed

    Wilkes, Rebecca P; Lee, Pei-Yu A; Tsai, Yun-Long; Tsai, Chuan-Fu; Chang, Hsiu-Hui; Chang, Hsiao-Fen G; Wang, Hwa-Tang T

    2015-08-01

    Canine parvovirus type 2 (CPV-2), including subtypes 2a, 2b and 2c, causes an acute enteric disease in both domestic and wild animals. Rapid and sensitive diagnosis aids effective disease management at points of need (PON). A commercially available, field-deployable and user-friendly system, designed with insulated isothermal PCR (iiPCR) technology, displays excellent sensitivity and specificity for nucleic acid detection. An iiPCR method was developed for on-site detection of all circulating CPV-2 strains. Limit of detection was determined using plasmid DNA. CPV-2a, 2b and 2c strains, a feline panleukopenia virus (FPV) strain, and nine canine pathogens were tested to evaluate assay specificity. Reaction sensitivity and performance were compared with an in-house real-time PCR using serial dilutions of a CPV-2b strain and 100 canine fecal clinical samples collected from 2010 to 2014, respectively. The 95% limit of detection of the iiPCR method was 13 copies of standard DNA and detection limits for CPV-2b DNA were equivalent for iiPCR and real-time PCR. The iiPCR reaction detected CPV-2a, 2b and 2c and FPV. Non-targeted pathogens were not detected. Test results of real-time PCR and iiPCR from 99 fecal samples agreed with each other, while one real-time PCR-positive sample tested negative by iiPCR. Therefore, excellent agreement (k = 0.98) with sensitivity of 98.41% and specificity of 100% in detecting CPV-2 in feces was found between the two methods. In conclusion, the iiPCR system has potential to serve as a useful tool for rapid and accurate PON, molecular detection of CPV-2. PMID:25889355

  20. Foodborne viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Testing for human pathogenic viruses in foods represents a formidable task requiring the extraction, concentration, and assay of a host of viruses from a wide range of food matrices. The enteric viruses, particularly genogroup I and II (GI and GII) noroviruses and hepatitis A virus, are the princip...

  1. Inventing Viruses.

    PubMed

    Summers, William C

    2014-11-01

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

  2. Serosurvey of small carnivores in the Bolivian Chaco.

    PubMed

    Fiorello, Christine V; Noss, Andrew J; Deem, Sharon L; Maffei, Leonardo; Dubovi, Edward J

    2007-07-01

    Five species of Bolivian carnivores, including nine Geoffroy's cats (Oncifelis geoffroyi), ten ocelots (Leopardus pardalis), one jaguarundi (Herpailurus yaguarondi), nine pampas foxes (Pseudalopex gymnocercus), and five crab-eating foxes (Cerdocyon thous) were sampled between March 2001 and April 2005 and tested for antibodies to common pathogens of domestic carnivores. Carnivores were trapped in three areas: a village, the region between human settlements and a protected area, and within Kaa-Iya National Park, Bolivia. Antibodies to canine distemper virus were detected in ocelots and pampas foxes. Antibodies to canine parvovirus were detected in pampas foxes and crab-eating foxes. Geoffroy's cats and all of the ocelots tested positive for antibodies to feline calicivirus (FCV), while fewer than half of Geoffroy's cats and no ocelots had antibodies to feline panleukopenia (FPV). These results confirm that these species of Bolivian carnivores are not naïve to common pathogens of domestic carnivores, and seropositive animals were found in villages as well as in the national park. PMID:17699100

  3. Two Novel Relative Double-Stranded RNA Mycoviruses Infecting Fusarium poae Strain SX63

    PubMed Central

    Wang, Luan; Zhang, Jingze; Zhang, Hailong; Qiu, Dewen; Guo, Lihua

    2016-01-01

    Two novel double-stranded RNA (dsRNA) mycoviruses, termed Fusarium poae dsRNA virus 2 (FpV2) and Fusarium poae dsRNA virus 3 (FpV3), were isolated from the plant pathogenic fungus, Fusarium poae strain SX63, and molecularly characterized. FpV2 and FpV3, with respective genome sequences of 9518 and 9419 base pairs (bps), are both predicted to contain two discontinuous open reading frames (ORFs), ORF1 and ORF2. A hypothetical polypeptide (P1) and a RNA-dependent RNA polymerase (RdRp) are encoded by ORF1 and ORF2, respectively. Phytoreo_S7 domain (pfam07236) homologs were detected downstream of the RdRp domain (RdRp_4; pfam02123) of the ORF2-coded proteins of both FpV2 and FpV3. The same shifty heptamers (GGAAAAC) were both found immediately before the stop codon UAG of ORF1 in FpV2 and FpV3, which could mediate programmed –1 ribosomal frameshifting (–1 PRF). Phylogenetic analysis based on RdRp sequences clearly place FpV2 and FpV3 in a taxonomically unassigned dsRNA mycovirus group. Together, with a comparison of genome organization, a new taxonomic family termed Fusagraviridae is proposed to be created to include FpV2- and FpV3-related dsRNA mycoviruses, within which FpV2 and FpV3 would represent two distinct virus species. PMID:27144564

  4. Zika Virus

    MedlinePlus

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

  5. Zika Virus

    MedlinePlus

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

  6. Zika Virus

    MedlinePlus

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

  7. Chikungunya Virus

    MedlinePlus

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

  8. Hepadna viruses

    SciTech Connect

    Robinson, W.; Koike, K.; Will, H.

    1987-01-01

    This book examines the molecular biology, disease pathogenesis, epidemiology, and clinical features of hepadna and other viruses with hepatic tropism and outlines future directions and approaches for their management. The volume's six sections provide a review of the various features, mechanisms, and functions of these viruses, ranging from hepadna virus replication and regulation of gene expression to the structure and function of hepadna-virus gene products.

  9. ECHO virus

    MedlinePlus

    Enteric cytopathic human orphan (ECHO) viruses are a group of viruses that lead to gastrointestinal infection and skin rashes. ... Echovirus is one of several families of viruses that affect the ... are common. In the United States, they are most common in ...

  10. Zika virus.

    PubMed

    2016-02-10

    Essential facts Zika virus disease is caused by a virus that is transmitted by the Aedes mosquito. While it generally causes a mild illness, there is increasing concern that it is harmful in pregnancy and can cause congenital abnormalities in infants born to women infected with the virus. There is no antiviral treatment or vaccine currently available. The best form of prevention is protection against mosquito bites. PMID:26860150

  11. CHLORELLA VIRUSES

    PubMed Central

    Yamada, Takashi; Onimatsu, Hideki; Van Etten, James L.

    2007-01-01

    Chlorella viruses or chloroviruses are large, icosahedral, plaque‐forming, double‐stranded‐DNA—containing viruses that replicate in certain strains of the unicellular green alga Chlorella. DNA sequence analysis of the 330‐kbp genome of Paramecium bursaria chlorella virus 1 (PBCV‐1), the prototype of this virus family (Phycodnaviridae), predict ∼366 protein‐encoding genes and 11 tRNA genes. The predicted gene products of ∼50% of these genes resemble proteins of known function, including many that are completely unexpected for a virus. In addition, the chlorella viruses have several features and encode many gene products that distinguish them from most viruses. These products include: (1) multiple DNA methyltransferases and DNA site‐specific endonucleases, (2) the enzymes required to glycosylate their proteins and synthesize polysaccharides such as hyaluronan and chitin, (3) a virus‐encoded K+ channel (called Kcv) located in the internal membrane of the virions, (4) a SET domain containing protein (referred to as vSET) that dimethylates Lys27 in histone 3, and (5) PBCV‐1 has three types of introns; a self‐splicing intron, a spliceosomal processed intron, and a small tRNA intron. Accumulating evidence indicates that the chlorella viruses have a very long evolutionary history. This review mainly deals with research on the virion structure, genome rearrangements, gene expression, cell wall degradation, polysaccharide synthesis, and evolution of PBCV‐1 as well as other related viruses. PMID:16877063

  12. Live Virus Smallpox Vaccine

    MedlinePlus

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

  13. Different levels of immunogenicity of two strains of Fowlpox virus as recombinant vaccine vectors eliciting T-cell responses in heterologous prime-boost vaccination strategies.

    PubMed

    Cottingham, Matthew G; van Maurik, Andre; Zago, Manola; Newton, Angela T; Anderson, Richard J; Howard, M Keith; Schneider, Jörg; Skinner, Michael A

    2006-07-01

    The FP9 strain of F has been described as a more immunogenic recombinant vaccine vector than the Webster FPV-M (FPW) strain (R. J. Anderson et al., J. Immunol. 172:3094-3100, 2004). This study expands the comparison to include two separate recombinant antigens and multiple, rather than single, independent viral clones derived from the two strains. Dual-poxvirus heterologous prime-boost vaccination regimens using individual clones of recombinant FP9 or FPW in combination with recombinant modified V Ankara expressing the same antigen were evaluated for their ability to elicit T-cell responses against recombinant antigens from Plasmodium berghei (circumsporozoite protein) or human immunodeficiency virus type 1 (a Gag-Pol-Nef fusion protein). Gamma interferon enzyme-linked immunospot assay and fluorescence-activated cell sorting assays of the responses to specific epitopes confirmed the approximately twofold-greater cellular immunogenicity of FP9 compared to FPW, when given as the priming or boosting immunization. Equality of transgene expression in mouse cells infected with the two strains in vitro was verified by Western blotting. Directed partial sequence analysis and PCR analysis of FPW and comparison to available whole-genome sequences revealed that many loci that are mutated in the highly attenuated and culture-adapted FP9 strain are wild type in FPW, including the seven multikilobase deletions. These "passage-specific" alterations are hypothesized to be involved in determining the immunogenicity of fowlpox virus as a recombinant vaccine vector. PMID:16829611

  14. A Rapid Screening Assay Identifies Monotherapy with Interferon-ß and Combination Therapies with Nucleoside Analogs as Effective Inhibitors of Ebola Virus

    PubMed Central

    McCarthy, Stephen D. S.; Majchrzak-Kita, Beata; Racine, Trina; Kozlowski, Hannah N.; Baker, Darren P.; Hoenen, Thomas; Kobinger, Gary P.; Fish, Eleanor N.; Branch, Donald R.

    2016-01-01

    To date there are no approved antiviral drugs for the treatment of Ebola virus disease (EVD). While a number of candidate drugs have shown limited efficacy in vitro and/or in non-human primate studies, differences in experimental methodologies make it difficult to compare their therapeutic effectiveness. Using an in vitro model of Ebola Zaire replication with transcription-competent virus like particles (trVLPs), requiring only level 2 biosafety containment, we compared the activities of the type I interferons (IFNs) IFN-α and IFN-ß, a panel of viral polymerase inhibitors (lamivudine (3TC), zidovudine (AZT) tenofovir (TFV), favipiravir (FPV), the active metabolite of brincidofovir, cidofovir (CDF)), and the estrogen receptor modulator, toremifene (TOR), in inhibiting viral replication in dose-response and time course studies. We also tested 28 two- and 56 three-drug combinations against Ebola replication. IFN-α and IFN-ß inhibited viral replication 24 hours post-infection (IC50 0.038μM and 0.016μM, respectively). 3TC, AZT and TFV inhibited Ebola replication when used alone (50–62%) or in combination (87%). They exhibited lower IC50 (0.98–6.2μM) compared with FPV (36.8μM), when administered 24 hours post-infection. Unexpectedly, CDF had a narrow therapeutic window (6.25–25μM). When dosed >50μM, CDF treatment enhanced viral infection. IFN-ß exhibited strong synergy with 3TC (97.3% inhibition) or in triple combination with 3TC and AZT (95.8% inhibition). This study demonstrates that IFNs and viral polymerase inhibitors may have utility in EVD. We identified several 2 and 3 drug combinations with strong anti-Ebola activity, confirmed in studies using fully infectious ZEBOV, providing a rationale for testing combination therapies in animal models of lethal Ebola challenge. These studies open up new possibilities for novel therapeutic options, in particular combination therapies, which could prevent and treat Ebola infection and potentially reduce drug

  15. A Rapid Screening Assay Identifies Monotherapy with Interferon-ß and Combination Therapies with Nucleoside Analogs as Effective Inhibitors of Ebola Virus.

    PubMed

    McCarthy, Stephen D S; Majchrzak-Kita, Beata; Racine, Trina; Kozlowski, Hannah N; Baker, Darren P; Hoenen, Thomas; Kobinger, Gary P; Fish, Eleanor N; Branch, Donald R

    2016-01-01

    To date there are no approved antiviral drugs for the treatment of Ebola virus disease (EVD). While a number of candidate drugs have shown limited efficacy in vitro and/or in non-human primate studies, differences in experimental methodologies make it difficult to compare their therapeutic effectiveness. Using an in vitro model of Ebola Zaire replication with transcription-competent virus like particles (trVLPs), requiring only level 2 biosafety containment, we compared the activities of the type I interferons (IFNs) IFN-α and IFN-ß, a panel of viral polymerase inhibitors (lamivudine (3TC), zidovudine (AZT) tenofovir (TFV), favipiravir (FPV), the active metabolite of brincidofovir, cidofovir (CDF)), and the estrogen receptor modulator, toremifene (TOR), in inhibiting viral replication in dose-response and time course studies. We also tested 28 two- and 56 three-drug combinations against Ebola replication. IFN-α and IFN-ß inhibited viral replication 24 hours post-infection (IC50 0.038μM and 0.016μM, respectively). 3TC, AZT and TFV inhibited Ebola replication when used alone (50-62%) or in combination (87%). They exhibited lower IC50 (0.98-6.2μM) compared with FPV (36.8μM), when administered 24 hours post-infection. Unexpectedly, CDF had a narrow therapeutic window (6.25-25μM). When dosed >50μM, CDF treatment enhanced viral infection. IFN-ß exhibited strong synergy with 3TC (97.3% inhibition) or in triple combination with 3TC and AZT (95.8% inhibition). This study demonstrates that IFNs and viral polymerase inhibitors may have utility in EVD. We identified several 2 and 3 drug combinations with strong anti-Ebola activity, confirmed in studies using fully infectious ZEBOV, providing a rationale for testing combination therapies in animal models of lethal Ebola challenge. These studies open up new possibilities for novel therapeutic options, in particular combination therapies, which could prevent and treat Ebola infection and potentially reduce drug

  16. Diseases Caused by Viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The symptoms, causal agents, epidemiology and management of important virus diseases in chickpea and lentil crops were reviewed in depth. The virus diseases include.Alflafa mosaic virus, Cucumber mosaiv virus, Faba bean necrotic yellows virus, Pea enation mosaic virus, Pea seed-borne mosaci virus,...

  17. Computer viruses

    NASA Technical Reports Server (NTRS)

    Denning, Peter J.

    1988-01-01

    The worm, Trojan horse, bacterium, and virus are destructive programs that attack information stored in a computer's memory. Virus programs, which propagate by incorporating copies of themselves into other programs, are a growing menace in the late-1980s world of unprotected, networked workstations and personal computers. Limited immunity is offered by memory protection hardware, digitally authenticated object programs,and antibody programs that kill specific viruses. Additional immunity can be gained from the practice of digital hygiene, primarily the refusal to use software from untrusted sources. Full immunity requires attention in a social dimension, the accountability of programmers.

  18. Hendra virus.

    PubMed

    Middleton, Deborah

    2014-12-01

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

  19. Zika Virus

    MedlinePlus

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

  20. Zika Virus.

    PubMed

    Phillips, Jennan A; Neyland, Anavernyel

    2016-08-01

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

  1. Computer Viruses. Technology Update.

    ERIC Educational Resources Information Center

    Ponder, Tim, Comp.; Ropog, Marty, Comp.; Keating, Joseph, Comp.

    This document provides general information on computer viruses, how to help protect a computer network from them, measures to take if a computer becomes infected. Highlights include the origins of computer viruses; virus contraction; a description of some common virus types (File Virus, Boot Sector/Partition Table Viruses, Trojan Horses, and…

  2. Parainfluenza Viruses

    PubMed Central

    Henrickson, Kelly J.

    2003-01-01

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

  3. Hendra virus

    PubMed Central

    Middleton, Deborah

    2014-01-01

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

  4. [Influenza virus].

    PubMed

    Juozapaitis, Mindaugas; Antoniukas, Linas

    2007-01-01

    Every year, especially during the cold season, many people catch an acute respiratory disease, namely flu. It is easy to catch this disease; therefore, it spreads very rapidly and often becomes an epidemic or a global pandemic. Airway inflammation and other body ailments, which form in a very short period, torment the patient several weeks. After that, the symptoms of the disease usually disappear as quickly as they emerged. The great epidemics of flu have rather unique characteristics; therefore, it is possible to identify descriptions of such epidemics in historic sources. Already in the 4th century bc, Hippocrates himself wrote about one of them. It is known now that flu epidemics emerge rather frequently, but there are no regular intervals between those events. The epidemics can differ in their consequences, but usually they cause an increased mortality of elderly people. The great flu epidemics of the last century took millions of human lives. In 1918-19, during "The Spanish" pandemic of flu, there were around 40-50 millions of deaths all over the world; "Pandemic of Asia" in 1957 took up to one million lives, etc. Influenza virus can cause various disorders of the respiratory system: from mild inflammations of upper airways to acute pneumonia that finally results in the patient's death. Scientist Richard E. Shope, who investigated swine flu in 1920, had a suspicion that the cause of this disease might be a virus. Already in 1933, scientists from the National Institute for Medical Research in London - Wilson Smith, Sir Christopher Andrewes, and Sir Patrick Laidlaw - for the first time isolated the virus, which caused human flu. Then scientific community started the exhaustive research of influenza virus, and the great interest in this virus and its unique features is still active even today. PMID:18182834

  5. The Geometry of Viruses.

    ERIC Educational Resources Information Center

    Case, Christine L.

    1991-01-01

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

  6. Plant Virus Metagenomics: Advances in Virus Discovery.

    PubMed

    Roossinck, Marilyn J; Martin, Darren P; Roumagnac, Philippe

    2015-06-01

    In recent years plant viruses have been detected from many environments, including domestic and wild plants and interfaces between these systems-aquatic sources, feces of various animals, and insects. A variety of methods have been employed to study plant virus biodiversity, including enrichment for virus-like particles or virus-specific RNA or DNA, or the extraction of total nucleic acids, followed by next-generation deep sequencing and bioinformatic analyses. All of the methods have some shortcomings, but taken together these studies reveal our surprising lack of knowledge about plant viruses and point to the need for more comprehensive studies. In addition, many new viruses have been discovered, with most virus infections in wild plants appearing asymptomatic, suggesting that virus disease may be a byproduct of domestication. For plant pathologists these studies are providing useful tools to detect viruses, and perhaps to predict future problems that could threaten cultivated plants. PMID:26056847

  7. Measles virus

    PubMed Central

    Naim, Hussein Y

    2014-01-01

    Measles was an inevitable infection during the human development with substantial degree of morbidity and mortality. The severity of measles virus (MV) infection was largely contained by the development of a live attenuated vaccine that was introduced into the vaccination programs. However, all efforts to eradicate the disease failed and continued to annually result in significant deaths. The development of molecular biology techniques allowed the rescue of MV from cDNA that enabled important insights into a variety of aspects of the biology of the virus and its pathogenesis. Subsequently these technologies facilitated the development of novel vaccine candidates that induce immunity against measles and other pathogens. Based on the promising prospective, the use of MV as a recombinant vaccine and a therapeutic vector is addressed. PMID:25483511

  8. Zika Virus.

    PubMed

    Musso, Didier; Gubler, Duane J

    2016-07-01

    Zika virus (ZIKV) is an arthropod-borne virus (arbovirus) in the genus Flavivirus and the family Flaviviridae. ZIKV was first isolated from a nonhuman primate in 1947 and from mosquitoes in 1948 in Africa, and ZIKV infections in humans were sporadic for half a century before emerging in the Pacific and the Americas. ZIKV is usually transmitted by the bite of infected mosquitoes. The clinical presentation of Zika fever is nonspecific and can be misdiagnosed as other infectious diseases, especially those due to arboviruses such as dengue and chikungunya. ZIKV infection was associated with only mild illness prior to the large French Polynesian outbreak in 2013 and 2014, when severe neurological complications were reported, and the emergence in Brazil of a dramatic increase in severe congenital malformations (microcephaly) suspected to be associated with ZIKV. Laboratory diagnosis of Zika fever relies on virus isolation or detection of ZIKV-specific RNA. Serological diagnosis is complicated by cross-reactivity among members of the Flavivirus genus. The adaptation of ZIKV to an urban cycle involving humans and domestic mosquito vectors in tropical areas where dengue is endemic suggests that the incidence of ZIKV infections may be underestimated. There is a high potential for ZIKV emergence in urban centers in the tropics that are infested with competent mosquito vectors such as Aedes aegypti and Aedes albopictus. PMID:27029595

  9. SAMPLING VIRUSES FROM SOIL

    EPA Science Inventory

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

  10. Computer Viruses: An Overview.

    ERIC Educational Resources Information Center

    Marmion, Dan

    1990-01-01

    Discusses the early history and current proliferation of computer viruses that occur on Macintosh and DOS personal computers, mentions virus detection programs, and offers suggestions for how libraries can protect themselves and their users from damage by computer viruses. (LRW)

  11. Hanta virus (image)

    MedlinePlus

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

  12. Ebola Virus Disease

    MedlinePlus

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

  13. Virus Movement Maintains Local Virus Population Diversity

    SciTech Connect

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

    2007-11-01

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

  14. Virus movement maintains local virus population diversity.

    PubMed

    Snyder, Jamie C; Wiedenheft, Blake; Lavin, Matthew; Roberto, Francisco F; Spuhler, Josh; Ortmann, Alice C; Douglas, Trevor; Young, Mark

    2007-11-27

    Viruses are the largest reservoir of genetic material on the planet, yet little is known about the population dynamics of any virus within its natural environment. Over a 2-year period, we monitored the diversity of two archaeal viruses found in hot springs within Yellowstone National Park (YNP). Both temporal phylogeny and neutral biodiversity models reveal that virus diversity in these local environments is not being maintained by mutation but rather by high rates of immigration from a globally distributed metacommunity. These results indicate that geographically isolated hot springs are readily able to exchange viruses. The importance of virus movement is supported by the detection of virus particles in air samples collected over YNP hot springs and by their detection in metacommunity sequencing projects conducted in the Sargasso Sea. Rapid rates of virus movement are not expected to be unique to these archaeal viruses but rather a common feature among virus metacommunities. The finding that virus immigration rather than mutation can dominate community structure has significant implications for understanding virus circulation and the role that viruses play in ecology and evolution by providing a reservoir of mobile genetic material. PMID:18025457

  15. Viruses and Virus Diseases of Rubus

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  16. Virophages or satellite viruses?

    PubMed

    Krupovic, Mart; Cvirkaite-Krupovic, Virginija

    2011-11-01

    It has been argued that the smaller viruses associated with giant DNA viruses are a new biological entity. However, Mart Krupovic and Virginija Cvirkaite-Krupovic argue here that these smaller viruses should be classified with the satellite viruses. PMID:22016897

  17. The Tobacco Mosaic Virus.

    ERIC Educational Resources Information Center

    Sulzinski, Michael A.

    1992-01-01

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

  18. Virus-Vectored Influenza Virus Vaccines

    PubMed Central

    Tripp, Ralph A.; Tompkins, S. Mark

    2014-01-01

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

  19. Viruses Infecting Reptiles

    PubMed Central

    Marschang, Rachel E.

    2011-01-01

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

  20. Morphogenesis of Bittner Virus

    PubMed Central

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

    1970-01-01

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

  1. Raspberry (Rubus spp.)-Viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There are several important virus diseases of raspberry and black raspberry in the Pacific Northwest. Pollen-borne viruses include Raspberry bushy dwarf virus and Strawberry necrotic shock virus (aka Tobacco streak virus –Rubus isolate or Black raspberry latent virus). Strawberry necrotic shock viru...

  2. Tumorigenic DNA viruses

    SciTech Connect

    Klein, G.

    1989-01-01

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

  3. Zika Virus Fact Sheet

    MedlinePlus

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

  4. Viruses and Breast Cancer

    PubMed Central

    Lawson, James S.; Heng, Benjamin

    2010-01-01

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

  5. Respiratory Syncytial Virus Infections

    MedlinePlus

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

  6. Human Parainfluenza Viruses

    MedlinePlus

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

  7. Advances in virus research

    SciTech Connect

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

    1988-01-01

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

  8. Herpes Simplex Virus (HSV)

    MedlinePlus

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

  9. Virus Assembly and Maturation

    NASA Astrophysics Data System (ADS)

    Johnson, John E.

    2004-03-01

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

  10. West Nile virus

    MedlinePlus

    West Nile virus is a disease spread by mosquitoes. The condition ranges from mild to severe. ... West Nile virus was first identified in 1937 in Uganda in eastern Africa. It was first discovered in the U.S. in ...

  11. Hepatitis D Virus Replication.

    PubMed

    Taylor, John M

    2015-11-01

    This work reviews specific related aspects of hepatitis delta virus (HDV) reproduction, including virion structure, the RNA genome, the mode of genome replication, the delta antigens, and the assembly of HDV using the envelope proteins of its helper virus, hepatitis B virus (HBV). These topics are considered with perspectives ranging from a history of discovery through to still-unsolved problems. HDV evolution, virus entry, and associated pathogenic potential and treatment of infections are considered in other articles in this collection. PMID:26525452

  12. Avian influenza virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  13. Computer Virus Protection

    ERIC Educational Resources Information Center

    Rajala, Judith B.

    2004-01-01

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

  14. Respiratory Syncytial Virus

    MedlinePlus

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

  15. BOVINE VIRAL DIARRHEA VIRUSES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bovine viral diarrhea virus (BVDV) is an umbrella term for two species of viruses, BVDV1 and BVDV2, within the Pestivirus genus of the Flavivirus family. BVDV viruses are further subclassified as cytopathic and noncytopathic based on their activity in cultured epithelial cells. Noncytopathic BVDV p...

  16. The taxonomy of viruses should include viruses.

    PubMed

    Calisher, Charles H

    2016-05-01

    Having lost sight of its goal, the International Committee on Taxonomy of Viruses has redoubled its efforts. That goal is to arrive at a consensus regarding virus classification, i.e., proper placement of viruses in a hierarchical taxonomic scheme; not an easy task given the wide variety of recognized viruses. Rather than suggesting a continuation of the bureaucratic machinations of the past, this opinion piece is a call for insertion of common sense in sorting out the avalanche of information already, and soon-to-be, accrued data. In this way information about viruses ideally would be taxonomically correct as well as useful to working virologists and journal editors, rather than being lost, minimized, or ignored. PMID:26914357

  17. Blueberry (Vaccinium corymbosum)-Virus Diseases

    Technology Transfer Automated Retrieval System (TEKTRAN)

    At least six viruses have been found in highbush blueberry plantings in the Pacific Northwest: Blueberry mosaic virus, Blueberry red ringspot virus, Blueberry scorch virus, Blueberry shock virus, Tobacco ringspot virus, and Tomato ringspot virus. Six other virus and virus-like diseases of highbush b...

  18. Heterologous prime-boost-boost immunisation of Chinese cynomolgus macaques using DNA and recombinant poxvirus vectors expressing HIV-1 virus-like particles

    PubMed Central

    2011-01-01

    Background There is renewed interest in the development of poxvirus vector-based HIV vaccines due to the protective effect observed with repeated recombinant canarypox priming with gp120 boosting in the recent Thai placebo-controlled trial. This study sought to investigate whether a heterologous prime-boost-boost vaccine regimen in Chinese cynomolgus macaques with a DNA vaccine and recombinant poxviral vectors expressing HIV virus-like particles bearing envelopes derived from the most prevalent clades circulating in sub-Saharan Africa, focused the antibody response to shared neutralising epitopes. Methods Three Chinese cynomolgus macaques were immunised via intramuscular injections using a regimen composed of a prime with two DNA vaccines expressing clade A Env/clade B Gag followed by boosting with recombinant fowlpox virus expressing HIV-1 clade D Gag, Env and cholera toxin B subunit followed by the final boost with recombinant modified vaccinia virus Ankara expressing HIV-1 clade C Env, Gag and human complement protein C3d. We measured the macaque serum antibody responses by ELISA, enumerated T cell responses by IFN-γ ELISpot and assessed seroneutralisation of HIV-1 using the TZM-bl β-galactosidase assay with primary isolates of HIV-1. Results This study shows that large and complex synthetic DNA sequences can be successfully cloned in a single step into two poxvirus vectors: MVA and FPV and the recombinant poxviruses could be grown to high titres. The vaccine candidates showed appropriate expression of recombinant proteins with the formation of authentic HIV virus-like particles seen on transmission electron microscopy. In addition the b12 epitope was shown to be held in common by the vaccine candidates using confocal immunofluorescent microscopy. The vaccine candidates were safely administered to Chinese cynomolgus macaques which elicited modest T cell responses at the end of the study but only one out of the three macaques elicited an HIV-specific antibody

  19. Viruses of asparagus.

    PubMed

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

    2012-01-01

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

  20. [Viruses as biological weapons].

    PubMed

    Akçali, Alper

    2005-07-01

    The destruction made by nuclear, biological and chemical weapons used by governments and terrorist groups in the near history is posing anxiety and fear for human being. Rumour about the possible use of these agents leads to the development of serious negative effects on populations. Since there are no vaccine and therapy for most viral agents and cost of production as biological weapons is low, interest rate is rising for viruses. In this review, general characteristics, diagnosis, therapy and protective measures for viral agents such as variola virus, hemorrhagic fever viruses, encephalitis viruses, Hantaviruses and Nipah viruses, those can be used as biological weapon, have been summarized. PMID:16358499

  1. Online identification of viruses.

    PubMed

    Kolaskar, A S; Naik, P S

    2000-06-01

    A computerized animal virus information system is developed in the Sequence Retrieval System (SRS) format. This database is available on the Word Wide Web (WWW) at the site http://bioinfo.ernet.in/www/avis/avis++ +.html. The database has been used to generate large number of identification matrices for each family. The software is developed in C. Unix shell scripts and Hypertext Marked-up Language (HTML) to assign the family to an unknown virus deterministically and to identify the virus probabilistically. It has been shown that such web based virus identification approach provides results with high confidence in those cases where identification matrix uses large number of independent characters. Protein sequence data for animal viruses have been analyzed and oligopeptides specific to each virus family and also specific to each virus species are identified for several viruses. These peptides thus could be used to identify the virus and to assign the virus family with high confidence showing the usefulness of sequence data in virus identification. PMID:10917875

  2. Serodiagnosis for Tumor Viruses

    PubMed Central

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

    2015-01-01

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

  3. Lipids of Archaeal Viruses

    PubMed Central

    Roine, Elina; Bamford, Dennis H.

    2012-01-01

    Archaeal viruses represent one of the least known territory of the viral universe and even less is known about their lipids. Based on the current knowledge, however, it seems that, as in other viruses, archaeal viral lipids are mostly incorporated into membranes that reside either as outer envelopes or membranes inside an icosahedral capsid. Mechanisms for the membrane acquisition seem to be similar to those of viruses infecting other host organisms. There are indications that also some proteins of archaeal viruses are lipid modified. Further studies on the characterization of lipids in archaeal viruses as well as on their role in virion assembly and infectivity require not only highly purified viral material but also, for example, constant evaluation of the adaptability of emerging technologies for their analysis. Biological membranes contain proteins and membranes of archaeal viruses are not an exception. Archaeal viruses as relatively simple systems can be used as excellent tools for studying the lipid protein interactions in archaeal membranes. PMID:23049284

  4. RNA Viruses Infecting Pest Insects

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  5. Postmortem stability of Ebola virus.

    PubMed

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

    2015-05-01

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

  6. Lifestyles of plant viruses

    PubMed Central

    Roossinck, Marilyn J.

    2010-01-01

    The vast majority of well-characterized eukaryotic viruses are those that cause acute or chronic infections in humans and domestic plants and animals. However, asymptomatic persistent viruses have been described in animals, and are thought to be sources for emerging acute viruses. Although not previously described in these terms, there are also many viruses of plants that maintain a persistent lifestyle. They have been largely ignored because they do not generally cause disease. The persistent viruses in plants belong to the family Partitiviridae or the genus Endornavirus. These groups also have members that infect fungi. Phylogenetic analysis of the partitivirus RNA-dependent RNA polymerase genes suggests that these viruses have been transmitted between plants and fungi. Additional families of viruses traditionally thought to be fungal viruses are also found frequently in plants, and may represent a similar scenario of persistent lifestyles, and some acute or chronic viruses of crop plants may maintain a persistent lifestyle in wild plants. Persistent, chronic and acute lifestyles of plant viruses are contrasted from both a functional and evolutionary perspective, and the potential role of these lifestyles in host evolution is discussed. PMID:20478885

  7. Viruses of lower vertebrates.

    PubMed

    Essbauer, S; Ahne, W

    2001-08-01

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

  8. Vaccinia virus transcription.

    PubMed

    Broyles, Steven S

    2003-09-01

    Vaccinia virus replication takes place in the cytoplasm of the host cell. The nearly 200 kbp genome owes part of its complexity to encoding most of the proteins involved in genome and mRNA synthesis. The multisubunit vaccinia virus RNA polymerase requires a separate set of virus-encoded proteins for the transcription of the early, intermediate and late classes of genes. Cell fractionation studies have provided evidence for a role for host cell proteins in the initiation and termination of vaccinia virus intermediate and late gene transcription. Vaccinia virus resembles nuclear DNA viruses in the integration of viral and host proteins for viral mRNA synthesis, yet is markedly less reliant on host proteins than its nuclear counterparts. PMID:12917449

  9. Viruses in Antarctic lakes

    NASA Technical Reports Server (NTRS)

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

    1998-01-01

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

  10. Constructing computer virus phylogenies

    SciTech Connect

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

    1996-03-01

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

  11. Water system virus detection

    NASA Technical Reports Server (NTRS)

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

    1978-01-01

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

  12. The human oncogenic viruses

    SciTech Connect

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

    1986-01-01

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

  13. Water system virus detection

    NASA Technical Reports Server (NTRS)

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

    1975-01-01

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

  14. Residual viruses in pork products.

    PubMed

    McKercher, P D; Hess, W R; Hamdy, F

    1978-01-01

    Partly cooked canned hams and dried pepperoni and salami sausages were prepared from the carcasses of pigs infected with African swine fever virus and pigs infected with hog cholera virus. Virus was not recovered from the partly cooked canned hams; however, virus was recovered in the hams before heating in both instances. Both African swine fever virus and hog cholera virus were recovered from the dried salami and pepperoni sausages, but not after the required curing period. PMID:564162

  15. Ferric-pyoverdine recognition by Fpv outer-membrane proteins of Pseudomonas protegens Pf-5

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The soil bacterium Pseudomonas protegens Pf-5 (previously called P. fluorescens Pf-5) produces two siderophores, enantio-pyochelin and a compound in the large and diverse pyoverdine family. Using high-resolution mass spectroscopy, we determined the structure of the pyoverdine produced by Pf-5. In ad...

  16. INFLUENZA VIRUS IN POULTRY

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza virus (AIV) is normally found in wild birds, particularly in ducks and shorebirds, where it does not cause any perceptible clinical disease. However, poultry, including chickens and turkeys, are not normal hosts for avian influenza, but if the virus is introduced it can result in mi...

  17. Zika Virus Disease.

    PubMed

    Slenczka, Werner

    2016-06-01

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

  18. Human Papilloma Virus Infections

    PubMed Central

    Wright, V. Cecil

    1989-01-01

    Genital warts are believed to be caused by human papilloma viruses and to be sexually transmitted. The viruses are classified by DNA types, which appear to cause different types of disease. The choice of treatment, and usually its success rate, vary according to the type of disease and its location. PMID:21248973

  19. Barley Yellow Dwarf Virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Barley yellow dwarf (BYD) is the most widespread and economically important virus disease of cereals. The viruses causing BYD were initially grouped based on common biological properties, including persistent and often strain-specific transmission by aphids and induction of yellowing symptoms. The...

  20. Influenza A virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Influenza A viruses are important veterinary and human health pathogens around the world. Avian influenza (AI) virus in poultry is unusual in that it can cause a range of disease symptoms from a subclinical infection to being highly virulent with 100% mortality. The difference between low pathogen...

  1. Zika Virus and Pregnancy.

    PubMed

    Stagg, Denise; Hurst, Helen M

    2016-01-01

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

  2. Papaya ringspot virus (Potyviridae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  3. Virus separation using membranes.

    PubMed

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

    2014-01-01

    Industrial manufacturing of cell culture-derived viruses or virus-like particles for gene therapy or vaccine production are complex multistep processes. In addition to the bioreactor, such processes require a multitude of downstream unit operations for product separation, concentration, or purification. Similarly, before a biopharmaceutical product can enter the market, removal or inactivation of potential viral contamination has to be demonstrated. Given the complexity of biological solutions and the high standards on composition and purity of biopharmaceuticals, downstream processing is the bottleneck in many biotechnological production trains. Membrane-based filtration can be an economically attractive and efficient technology for virus separation. Viral clearance, for instance, of up to seven orders of magnitude has been reported for state of the art polymeric membranes under best conditions.This chapter summarizes the fundamentals of virus ultrafiltration, diafiltration, or purification with adsorptive membranes. In lieu of an impractical universally applicable protocol for virus filtration, application of these principles is demonstrated with two examples. The chapter provides detailed methods for production, concentration, purification, and removal of a rod-shaped baculovirus (Autographa californica M nucleopolyhedrovirus, about 40 × 300 nm in size, a potential vector for gene therapy, and an industrially important protein expression system) or a spherical parvovirus (minute virus of mice, 22-26 nm in size, a model virus for virus clearance validation studies). PMID:24297430

  4. Papaya Ringspot Virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  5. Bovine viral diarrhea viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Infections with bovine viral diarrhea viruses (BVDV) result in significant economic losses for beef and dairy producers worldwide. BVDV is actually an umbrella term for two species of viruses, BVDV1 and BVDV2, within the Pestivirus genus of the Flavivirus family. While denoted as a bovine pathogen...

  6. Equine Arteritis Virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  7. Rift Valley Fever Virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  8. Respiratory viruses and children.

    PubMed

    Heikkinen, Terho

    2016-07-01

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

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

    PubMed

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

    2016-01-01

    The plaque assay is an essential method for quantification of infectious virus titer. Cells infected with virus particles are overlaid with a viscous substrate. A suitable incubation period results in the formation of plaques, which can be fixed and stained for visualization. Here, we describe a method for measuring Chikungunya virus (CHIKV) titers via virus plaque assays. PMID:27233264

  10. Postmortem Stability of Ebola Virus

    PubMed Central

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

    2015-01-01

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

  11. Tembusu Virus in Ducks, China

    PubMed Central

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

    2011-01-01

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

  12. Computer Viruses: Pathology and Detection.

    ERIC Educational Resources Information Center

    Maxwell, John R.; Lamon, William E.

    1992-01-01

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

  13. A Virus in Turbo Pascal.

    ERIC Educational Resources Information Center

    Teleky, Heidi Ann; And Others

    1993-01-01

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

  14. Realms of the Viruses Online

    ERIC Educational Resources Information Center

    Liu, Dennis

    2007-01-01

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

  15. Ocular Tropism of Respiratory Viruses

    PubMed Central

    Rota, Paul A.; Tumpey, Terrence M.

    2013-01-01

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

  16. Viruses of Chelonia.

    PubMed

    Ahne, W

    1993-02-01

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

  17. Foamy virus vectors.

    PubMed Central

    Russell, D W; Miller, A D

    1996-01-01

    Human foamy virus (HFV) is a retrovirus of the spumavirus family. We have constructed vectors based on HFV that encode neomycin phosphotransferase and alkaline phosphatase. These vectors are able to transduce a wide variety of vertebrate cells by integration of the vector genome. Unlike vectors based on murine leukemia virus, HFV vectors are not inactivated by human serum, and they transduce stationary-phase cultures more efficiently than murine leukemia virus vectors. These properties, as well as their large packaging capacity, make HFV vectors promising gene transfer vehicles. PMID:8523528

  18. Fighting cancer with viruses

    NASA Astrophysics Data System (ADS)

    Ferreira, S. C.; Martins, M. L.; Vilela, M. J.

    2005-01-01

    One of the most promising strategies to treat cancer is attacking it with viruses. Viruses can kill tumor cells specifically or act as carriers that deliver normal genes into cancer cells. A model for virotherapy of cancer is investigated and its predictions are in agreement with results obtained from experimental tumors. Furthermore, the model reveals an oscillatory (periodic or aperiodic) response of tumor cells and virus populations which may make clinical prognosis difficult. These results suggest the need for new in vivo and in vitro experiments aiming to detect this oscillatory response.

  19. Virus templated metallic nanoparticles.

    PubMed

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

    2010-12-01

    Plant viruses are considered as nanobuilding blocks that can be used as synthons or templates for novel materials. Cowpea mosaic virus (CPMV) particles have been shown to template the fabrication of metallic nanoparticles by an electroless deposition metallization process. Palladium ions were electrostatically bound to the virus capsid and, when reduced, acted as nucleation sites for the subsequent metal deposition from solution. The method, although simple, produced highly monodisperse metallic nanoparticles with a diameter of ca. ≤35 nm. CPMV-templated particles were prepared with cobalt, nickel, iron, platinum, cobalt-platinum and nickel-iron. PMID:20877898

  20. Viruses in reptiles

    PubMed Central

    2011-01-01

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

  1. How rigid are viruses

    NASA Astrophysics Data System (ADS)

    Hartschuh, R. D.; Wargacki, S. P.; Xiong, H.; Neiswinger, J.; Kisliuk, A.; Sihn, S.; Ward, V.; Vaia, R. A.; Sokolov, A. P.

    2008-08-01

    Viruses have traditionally been studied as pathogens, but in recent years they have been adapted for applications ranging from drug delivery and gene therapy to nanotechnology, photonics, and electronics. Although the structures of many viruses are known, most of their biophysical properties remain largely unexplored. Using Brillouin light scattering, we analyzed the mechanical rigidity, intervirion coupling, and vibrational eigenmodes of Wiseana iridovirus (WIV). We identified phonon modes propagating through the viral assemblies as well as the localized vibrational eigenmode of individual viruses. The measurements indicate a Young’s modulus of ˜7GPa for single virus particles and their assemblies, surprisingly high for “soft” materials. Mechanical modeling confirms that the DNA core dominates the WIV rigidity. The results also indicate a peculiar mechanical coupling during self-assembly of WIV particles.

  2. VIRUS instrument enclosures

    NASA Astrophysics Data System (ADS)

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

    2014-08-01

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

  3. Virus Chapter: Iflaviridae

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The iflaviruses comprise viruses isolated from arthropod species of agricultural importance. All members of iflaviruses have a genome arrangement similar to the picornaviruses, ootyviruses, and secoviruses. However, phylogenetic analysis using the RNA-dependent RNA polymerase region showed that th...

  4. [Zika, a neurotropic virus?].

    PubMed

    Del Carpio-Orantes, Luis

    2016-01-01

    In this paper, the neurotropism potential Zika virus is discussed, by comparison with viruses both RNA and DNA are neurotropic known, also it is said that compared with the new viruses that have affected the Americas, as the chikungunya, Zika has shown great affinity by brain tissue, manifested by a high incidence of acute neurological conditions, such as Guillain-Barré syndrome, among others, as well as the reported incidence of microcephaly that is abnormally high compared with the previous incidence, which, in a stillborn subject necropsied significant alterations demonstrated in brain tissue, identifying viral material and live virus in the fetoplacental complex, and demonstrating the impact both white matter and gray matter as well as basal ganglia, corpus callosum, ventricles and spinal cord, which could explain the microcephaly that concerns him. Although not a direct cause-effect relationship is demonstrated, however current evidence supports that relationship, hoping to be supported scientifically. PMID:27197113

  5. Sexually transmitted viruses.

    PubMed Central

    Rapp, F.

    1989-01-01

    Human viruses known to be spread by sexual contact include herpes simplex viruses (HSV), papillomaviruses (HPV), human immunodeficiency virus (HIV), hepatitis B virus, and cytomegalovirus. Infections with the first three (HSV, HPV, and HIV) have reached epidemic proportions and pose global health concerns. Most of what we know about these human pathogens has been learned only recently, owing to the advent of DNA technologies and advances in culture techniques. In fact, our awareness of one virally transmitted venereal disease, acquired immunodeficiency syndrome, dates to the early 1980s. This paper touches on various aspects of the biology, pathogenesis, clinical manifestations, and, where applicable, oncogenicity of these agents, as well as current treatments and vaccine initiatives. PMID:2549736

  6. West Nile Virus

    MedlinePlus

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

  7. Respiratory syncytial virus (RSV)

    MedlinePlus

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

  8. Hepatitis B virus (image)

    MedlinePlus

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

  9. Avoiding Computer Viruses.

    ERIC Educational Resources Information Center

    Rowe, Joyce; And Others

    1989-01-01

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

  10. What's West Nile Virus?

    MedlinePlus

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

  11. Ebola virus disease

    MedlinePlus

    ... urine, saliva, sweat, feces, vomit, breast milk, and semen. The virus can enter the body through a ... use condoms for 12 months or until their semen has twice tested negative. Long-term complications can ...

  12. Simian hemorrhagic fever virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This book chapter describes the taxonomic classification of Simian hemorrhagic fever virus (SHFV). Included are: host, genome, classification, morphology, physicochemical and physical properties, nucleic acid, proteins, lipids, carbohydrates, geographic range, phylogenetic properties, biological pro...

  13. The dengue viruses.

    PubMed

    Henchal, E A; Putnak, J R

    1990-10-01

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

  14. West Nile Virus

    MedlinePlus

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

  15. The dengue viruses.

    PubMed Central

    Henchal, E A; Putnak, J R

    1990-01-01

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

  16. Virus templated metallic nanoparticles

    NASA Astrophysics Data System (ADS)

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

    2010-12-01

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

  17. Tick-borne viruses*

    PubMed Central

    Work, Telford H.

    1963-01-01

    More than 150 arthropod-borne viruses are now recognized, and over 50 of these are known to produce human infections and disease. Among these viruses are those of the tick-borne Russian spring-summer complex, which is etiologically involved in a wide variety of human diseases of varying severity. The eight antigenically different members of this complex so far known are Russian spring-summer encephalitis, louping-ill, Central European encephalitis, Omsk haemorrhagic fever, Kyasanur Forest disease, Langat, Negishi and Powassan viruses. In his review of the problems posed by these viruses and of research on them, the author points out that, while this complex is distributed around the globe in the temperate zone of the northern hemisphere, the only serious tick-borne virus disease known in the tropics is Kyasanur Forest disease. It is probable, however, that there are other, unrecognized tick-borne viruses in the tropical areas of Asia, Africa and America of importance to human health, and that these will be brought to light as virological studies of diseases of now obscure etiology are pursued. PMID:14043753

  18. Control of cucurbit viruses.

    PubMed

    Lecoq, Hervé; Katis, Nikolaos

    2014-01-01

    More than 70 well-characterized virus species transmitted by a diversity of vectors may infect cucurbit crops worldwide. Twenty of those cause severe epidemics in major production areas, occasionally leading to complete crop failures. Cucurbit viruses' control is based on three major axes: (i) planting healthy seeds or seedlings in a clean environment, (ii) interfering with vectors activity, and (iii) using resistant cultivars. Seed disinfection and seed or seedling quality controls guarantee growers on the sanitary status of their planting material. Removal of virus or vector sources in the crop environment can significantly delay the onset of viral epidemics. Insecticide or oil application may reduce virus spread in some situations. Diverse cultural practices interfere with or prevent vector reaching the crop. Resistance can be obtained by grafting for soil-borne viruses, by cross-protection, or generally by conventional breeding or genetic engineering. The diversity of the actions that may be taken to limit virus spread in cucurbit crops and their limits will be discussed. The ultimate goal is to provide farmers with technical packages that combine these methods within an integrated disease management program and are adapted to different countries and cropping systems. PMID:25410104

  19. Human Influenza Virus Infections.

    PubMed

    Peteranderl, Christin; Herold, Susanne; Schmoldt, Carole

    2016-08-01

    Seasonal and pandemic influenza are the two faces of respiratory infections caused by influenza viruses in humans. As seasonal influenza occurs on an annual basis, the circulating virus strains are closely monitored and a yearly updated vaccination is provided, especially to identified risk populations. Nonetheless, influenza virus infection may result in pneumonia and acute respiratory failure, frequently complicated by bacterial coinfection. Pandemics are, in contrary, unexpected rare events related to the emergence of a reassorted human-pathogenic influenza A virus (IAV) strains that often causes increased morbidity and spreads extremely rapidly in the immunologically naive human population, with huge clinical and economic impact. Accordingly, particular efforts are made to advance our knowledge on the disease biology and pathology and recent studies have brought new insights into IAV adaptation mechanisms to the human host, as well as into the key players in disease pathogenesis on the host side. Current antiviral strategies are only efficient at the early stages of the disease and are challenged by the genomic instability of the virus, highlighting the need for novel antiviral therapies targeting the pulmonary host response to improve viral clearance, reduce the risk of bacterial coinfection, and prevent or attenuate acute lung injury. This review article summarizes our current knowledge on the molecular basis of influenza infection and disease progression, the key players in pathogenesis driving severe disease and progression to lung failure, as well as available and envisioned prevention and treatment strategies against influenza virus infection. PMID:27486731

  20. Transmission of influenza A viruses.

    PubMed

    Neumann, Gabriele; Kawaoka, Yoshihiro

    2015-05-01

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

  1. Transmission of Influenza A Viruses

    PubMed Central

    Neumann, Gabriele; Kawaoka, Yoshihiro

    2015-01-01

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

  2. Smaller Fleas: Viruses of Microorganisms

    PubMed Central

    Hyman, Paul; Abedon, Stephen T.

    2012-01-01

    Life forms can be roughly differentiated into those that are microscopic versus those that are not as well as those that are multicellular and those that, instead, are unicellular. Cellular organisms seem generally able to host viruses, and this propensity carries over to those that are both microscopic and less than truly multicellular. These viruses of microorganisms, or VoMs, in fact exist as the world's most abundant somewhat autonomous genetic entities and include the viruses of domain Bacteria (bacteriophages), the viruses of domain Archaea (archaeal viruses), the viruses of protists, the viruses of microscopic fungi such as yeasts (mycoviruses), and even the viruses of other viruses (satellite viruses). In this paper we provide an introduction to the concept of viruses of microorganisms, a.k.a., viruses of microbes. We provide broad discussion particularly of VoM diversity. VoM diversity currently spans, in total, at least three-dozen virus families. This is roughly ten families per category—bacterial, archaeal, fungal, and protist—with some virus families infecting more than one of these microorganism major taxa. Such estimations, however, will vary with further discovery and taxon assignment and also are dependent upon what forms of life one includes among microorganisms. PMID:24278736

  3. [Zika virus infection during pregnancy].

    PubMed

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

    2016-05-01

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

  4. Recombinant Vaccinia Virus: Immunization against Multiple Pathogens

    NASA Astrophysics Data System (ADS)

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

    1985-09-01

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

  5. Viruses and Multiple Sclerosis

    PubMed Central

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

    2012-01-01

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

  6. Nongenital herpes simplex virus.

    PubMed

    Usatine, Richard P; Tinitigan, Rochelle

    2010-11-01

    Nongenital herpes simplex virus type 1 is a common infection usually transmitted during childhood via nonsexual contact. Most of these infections involve the oral mucosa or lips (herpes labialis). The diagnosis of an infection with herpes simplex virus type 1 is usually made by the appearance of the lesions (grouped vesicles or ulcers on an erythematous base) and patient history. However, if uncertain, the diagnosis of herpes labialis can be made by viral culture, polymerase chain reaction, serology, direct fluorescent antibody testing, or Tzanck test. Other nonoral herpes simplex virus type 1 infections include herpetic keratitis, herpetic whitlow, herpes gladiatorum, and herpetic sycosis of the beard area. The differential diagnosis of nongenital herpes simplex virus infection includes aphthous ulcers, acute paronychia, varicella-zoster virus infection, herpangina, herpes gestationis (pemphigoid gestationis), pemphigus vulgaris, and Behçet syndrome. Oral acyclovir suspension is an effective treatment for children with primary herpetic gingivostomatitis. Oral acyclovir, valacyclovir, and famciclovir are effective in treating acute recurrence of herpes labialis (cold sores). Recurrences of herpes labialis may be diminished with daily oral acyclovir or valacyclovir. Topical acyclovir, penciclovir, and docosanol are optional treatments for recurrent herpes labialis, but they are less effective than oral treatment. PMID:21121552

  7. Respiratory syncytial virus bronchiolitis.

    PubMed Central

    Leung, Alexander K. C.; Kellner, James D.; Davies, H. Dele

    2005-01-01

    Respiratory syncytial virus, the most common cause of bronchiolitis, is the leading cause of infant hospitalization in developed countries and accounts for substantial mortality and morbidity in developing countries. Children at increased risk of developing severe bronchiolitis are those <6 weeks of age, those born prematurely and those with an underlying cardiopulmonary disorder or immunodeficiency. Approximately 80% of cases occur in the first year of life. By two years of age, virtually all children have been infected by at least one strain of the virus. Classically, respiratory syncytial virus bronchiolitis manifests as cough, wheezing and respiratory distress. The mainstay of treatment is supportive care, consisting of adequate fluid intake, antipyretics to control fever and use of supplemental oxygen if necessary. Frequent and meticulous hand-washing is the best measure to prevent secondary spread. Treatment of respiratory syncytial virus bronchiolitis beyond supportive care should be individualized. Palivizumab has been shown to be effective in preventing severe respiratory syncytial virus bronchiolitis in high-risk children when given prophylactically. In the majority of cases, the disease is usually self-limited. The mortality rate is <1% and occurs predominantly in children at high risk for severe disease. PMID:16396064

  8. Viruses and multiple sclerosis.

    PubMed

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

    2011-12-01

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

  9. Attenuation of Vaccinia Virus.

    PubMed

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

    2015-01-01

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

  10. Production of virus resistant plants

    DOEpatents

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

    1996-12-10

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

  11. Testing for Human Immunodeficiency Virus

    MedlinePlus

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

  12. Special Issue: Honey Bee Viruses

    PubMed Central

    Gisder, Sebastian; Genersch, Elke

    2015-01-01

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

  13. Chlorella viruses isolated in China

    SciTech Connect

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

    1988-09-01

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

  14. Epstein-Barr virus test

    MedlinePlus

    ... medlineplus.gov/ency/article/003513.htm Epstein-Barr virus antibody test To use the sharing features on this page, please enable JavaScript. Epstein-Barr virus antibody test is a blood test to detect ...

  15. Ebola (Ebola Virus Disease): Prevention

    MedlinePlus

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

  16. Ebola (Ebola Virus Disease): Transmission

    MedlinePlus

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

  17. Ebola (Ebola Virus Disease): Treatment

    MedlinePlus

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

  18. Ebola (Ebola Virus Disease): Diagnosis

    MedlinePlus

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

  19. Oncolytic viruses: finally delivering

    PubMed Central

    Seymour, Leonard W; Fisher, Kerry D

    2016-01-01

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

  20. Oncolytic viruses: finally delivering.

    PubMed

    Seymour, Leonard W; Fisher, Kerry D

    2016-02-16

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

  1. Pathobiology of avian influenza viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza virus causes serious disease in a wide variety of birds and mammals. Its natural hosts are wild aquatic birds, in which most infections are unapparent. Avian Influenza (AI) viruses are classified into 16 hemagglutinin (H1-16) and nine neuraminidase (N1-9) subtypes. Each virus has on...

  2. Detection of Lassa Virus, Mali

    PubMed Central

    Safronetz, David; Lopez, Job E.; Sogoba, Nafomon; Traore’, Sékou F.; Raffel, Sandra J.; Fischer, Elizabeth R.; Ebihara, Hideki; Branco, Luis; Garry, Robert F.; Schwan, Tom G.

    2010-01-01

    To determine whether Lassa virus was circulating in southern Mali, we tested samples from small mammals from 3 villages, including Soromba, where in 2009 a British citizen probably contracted a lethal Lassa virus infection. We report the isolation and genetic characterization of Lassa virus from an area previously unknown for Lassa fever. PMID:20587185

  3. Protecting Your Computer from Viruses

    ERIC Educational Resources Information Center

    Descy, Don E.

    2006-01-01

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

  4. Avian influenza virus RNA extraction

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  5. Computer Bytes, Viruses and Vaccines.

    ERIC Educational Resources Information Center

    Palmore, Teddy B.

    1989-01-01

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

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  7. An introduction to computer viruses

    SciTech Connect

    Brown, D.R.

    1992-03-01

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

  8. Hendra virus and Nipah virus animal vaccines.

    PubMed

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

    2016-06-24

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

  9. Ecology of prokaryotic viruses.

    PubMed

    Weinbauer, Markus G

    2004-05-01

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

  10. Relationship of lychnis ringspot virus to barley stripe mosaic virus and poa semilatent virus.

    PubMed

    Hunter, B G; Smith, J; Fattouh, F; Jackson, A O

    1989-01-01

    Barley stripe mosaic virus (BSMV), poa semilatent virus (PSLV), and lychnis ringspot virus (LRSV) have previously been assigned to the hordeivirus group because of similarities in their particle morphology, physicochemical properties and serological analyses. However, the serological relationships of the three viruses have not been determined by direct comparison. The present study evaluated the relatedness of these viruses by Western and dot immunoblotting and by nucleic acid hybridizations. Serological analyses of the coat proteins separated by gel electrophoresis and of intact virus particles bound to nitrocellulose membranes revealed that BSMV and PSLV are distantly related, but that they are more closely related to each other than to LRSV. The genomic RNAs of the viruses failed to cross-hybridize in northern hybridization tests conducted at different temperatures. These comparisons showed that BSMV, PSLV and LRSV are distinct viruses with little nucleotide sequence relatedness. Thus our data provide additional support for their inclusion as separate members of the hordeivirus group. PMID:2722469

  11. Research on computer virus database management system

    NASA Astrophysics Data System (ADS)

    Qi, Guoquan

    2011-12-01

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

  12. Zika Virus Outside Africa

    PubMed Central

    2009-01-01

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

  13. Schmallenberg virus infection.

    PubMed

    Wernike, K; Elbers, A; Beer, M

    2015-08-01

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

  14. Human Immunodeficiency Virus Prevention.

    PubMed

    Davis, Teaniese Latham; DiClemente, Ralph

    2016-04-01

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

  15. [ZIKA--VIRUS INFECTION].

    PubMed

    Velev, V

    2016-01-01

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

  16. Barley yellow dwarf viruses.

    PubMed

    Miller, W A; Rasochová, L

    1997-01-01

    Barley yellow dwarf viruses represent one of the most economically important and ubiquitous groups of plant viruses. This review focuses primarily on four research areas in which progress has been most rapid. These include (a) evidence supporting reclassification of BYDVs into two genera; (b) elucidation of gene function and novel mechanisms controlling gene expression; (c) initial forays into understanding the complex interactions between BYDV virions and their aphid vectors; and (d) replication of a BYDV satellite RNA. Economic losses, symptomatology, and means of control of BYD are also discussed. PMID:15012520

  17. Zika virus: Indian perspectives

    PubMed Central

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

    2016-01-01

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

  18. Zika virus: Indian perspectives.

    PubMed

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

    2016-05-01

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

  19. Viruses and viral proteins

    PubMed Central

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

    2014-01-01

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

  20. Junín Virus Pathogenesis and Virus Replication

    PubMed Central

    Grant, Ashley; Seregin, Alexey; Huang, Cheng; Kolokoltsova, Olga; Brasier, Allan; Peters, Clarence; Paessler, Slobodan

    2012-01-01

    Junín virus, the etiological agent of Argentine hemorrhagic fever, causes significant morbidity and mortality. The virus is spread through the aerosolization of host rodent excreta and endemic to the humid pampas of Argentina. Recently, significant progress has been achieved with the development of new technologies (e.g. reverse genetics) that have expanded knowledge about the pathogenesis and viral replication of Junín virus. We will review the pathogenesis of Junín virus in various animal models and the role of innate and adaptive immunity during infection. We will highlight current research regarding the role of molecular biology of Junín virus in elucidating virus attenuation. We will also summarize current knowledge on Junín virus pathogenesis focusing on the recent development of vaccines and potential therapeutics. PMID:23202466

  1. Bat flight and zoonotic viruses

    USGS Publications Warehouse

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

    2014-01-01

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

  2. Bat Flight and Zoonotic Viruses

    PubMed Central

    Cryan, Paul M.; Cunningham, Andrew A.; Fooks, Anthony R.; Hayman, David T.S.; Luis, Angela D.; Peel, Alison J.; Plowright, Raina K.; Wood, James L.N.

    2014-01-01

    Bats are sources of high viral diversity and high-profile zoonotic viruses worldwide. Although apparently not pathogenic in their reservoir hosts, some viruses from bats severely affect other mammals, including humans. Examples include severe acute respiratory syndrome coronaviruses, Ebola and Marburg viruses, and Nipah and Hendra viruses. Factors underlying high viral diversity in bats are the subject of speculation. We hypothesize that flight, a factor common to all bats but to no other mammals, provides an intensive selective force for coexistence with viral parasites through a daily cycle that elevates metabolism and body temperature analogous to the febrile response in other mammals. On an evolutionary scale, this host–virus interaction might have resulted in the large diversity of zoonotic viruses in bats, possibly through bat viruses adapting to be more tolerant of the fever response and less virulent to their natural hosts. PMID:24750692

  3. Satellite RNAs and Satellite Viruses.

    PubMed

    Palukaitis, Peter

    2016-03-01

    Satellite RNAs and satellite viruses are extraviral components that can affect either the pathogenicity, the accumulation, or both of their associated viruses while themselves being dependent on the associated viruses as helper viruses for their infection. Most of these satellite RNAs are noncoding RNAs, and in many cases, have been shown to alter the interaction of their helper viruses with their hosts. In only a few cases have the functions of these satellite RNAs in such interactions been studied in detail. In particular, work on the satellite RNAs of Cucumber mosaic virus and Turnip crinkle virus have provided novel insights into RNAs functioning as noncoding RNAs. These effects are described and potential roles for satellite RNAs in the processes involved in symptom intensification or attenuation are discussed. In most cases, models describing these roles involve some aspect of RNA silencing or its suppression, either directly or indirectly involving the particular satellite RNA. PMID:26551994

  4. Bat flight and zoonotic viruses.

    PubMed

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

    2014-05-01

    Bats are sources of high viral diversity and high-profile zoonotic viruses worldwide. Although apparently not pathogenic in their reservoir hosts, some viruses from bats severely affect other mammals, including humans. Examples include severe acute respiratory syndrome coronaviruses, Ebola and Marburg viruses, and Nipah and Hendra viruses. Factors underlying high viral diversity in bats are the subject of speculation. We hypothesize that flight, a factor common to all bats but to no other mammals, provides an intensive selective force for coexistence with viral parasites through a daily cycle that elevates metabolism and body temperature analogous to the febrile response in other mammals. On an evolutionary scale, this host-virus interaction might have resulted in the large diversity of zoonotic viruses in bats, possibly through bat viruses adapting to be more tolerant of the fever response and less virulent to their natural hosts. PMID:24750692

  5. From Shakespeare to Viruses

    ScienceCinema

    Sung-Hou Kim

    2010-01-08

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

  6. Raspberry leaf curl virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Raspberry leaf curl virus (RLCV) is limited to hosts in the genus Rubus and is transmitted persistently by the small raspberry aphid, Aphis rubicola Oestlund. It is found only in North America, principally in the northeastern United States and southeastern Canada and in the Rocky Mountain regions of...

  7. From Shakespeare to Viruses

    ScienceCinema

    Kim, Sung-Hou

    2013-05-29

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

  8. Turnip Yellow Mosaic Virus

    NASA Technical Reports Server (NTRS)

    2000-01-01

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

  9. Viruses of Haloarchaea

    PubMed Central

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

    2014-01-01

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

  10. Cold Facts about Viruses.

    ERIC Educational Resources Information Center

    Pea, Celeste; Sterling, Donna R.

    2002-01-01

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

  11. From Shakespeare to Viruses

    SciTech Connect

    Sung-Hou Kim

    2009-02-09

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

  12. From Shakespeare to Viruses

    SciTech Connect

    Kim, Sung-Hou

    2009-01-01

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

  13. VIRUSES IN GROUNDWATER

    EPA Science Inventory

    The microbial contamination of ground water is a serious problem that can result in large outbreaks of waterborne disease. The purpose of this article is to review the literature available on viruses in ground water in order to evaluate the present state-of-knowledge, assess the ...

  14. Newcastle disease virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Newcastle disease virus (NDV), a member of the Avulavirus genus in the Paramyxoviridae family, has a ribonucleic acid (RNA) genome that is negative sense, non-segmented, and single-stranded. The genome codes for six structural proteins: nucleocapsid, phosphoprotein, matrix, fusion, hemagglutinin-neu...

  15. Varicella zoster virus latency

    PubMed Central

    Eshleman, Emily; Shahzad, Aamir; Cohrs, Randall J

    2011-01-01

    Primary infection by varicella zoster virus (VZV) typically results in childhood chickenpox, at which time latency is established in the neurons of the cranial nerve, dorsal root and autonomic ganglia along the entire neuraxis. During latency, the histone-associated virus genome assumes a circular episomal configuration from which transcription is epigenetically regulated. The lack of an animal model in which VZV latency and reactivation can be studied, along with the difficulty in obtaining high-titer cell-free virus, has limited much of our understanding of VZV latency to descriptive studies of ganglia removed at autopsy and analogy to HSV-1, the prototype alphaherpesvirus. However, the lack of miRNA, detectable latency-associated transcript and T-cell surveillance during VZV latency highlight basic differences between the two neurotropic herpesviruses. This article focuses on VZV latency: establishment, maintenance and reactivation. Comparisons are made with HSV-1, with specific attention to differences that make these viruses unique human pathogens. PMID:21695042

  16. The FEFM Virus.

    ERIC Educational Resources Information Center

    Cjelli, Dirk

    1994-01-01

    Discussion of human performance technology (HPT) interventions focuses on requests for solutions to problems that involve conflict between the FEFM ("Fix 'em for me") Virus and the WIIFM ("What's in it for me?") Requirement. Building a relationship of mutual trust and confidence with the client and demonstrating responsiveness are advocated. (LRW)

  17. Cell injury with viruses.

    PubMed Central

    Tamm, I.

    1975-01-01

    The inhibitions of cellular protein and RNA synthesis in picornavirus-infected cells are early events which require only limited synthesis of virus-specific proteins. The inhibition of cellular protein synthesis appears to be due to blocking of the association of ribosomes with host messenger RNA. Inhibition of cellular RNA synthesis involves inactivation of the template-enzyme complex and affects ribosomal RNA synthesis before messenger RNA synthesis. Inhibition of cellular DNA synthesis also occurs early and may be secondary to inhibition of cellular protein synthesis. Early chromatid breaks may be related to inhibitions of cellular protein and nucleic acid synthesis. Stimulation of phospholipid synthesis in picornavirus-infected cells also requires only limited synthesis of virus-specific proteins. In contrast, release of lysosomal enzymes, proliferation of smooth cytoplasmic membranes, cellular vacuolization, retraction, and rounding, and diffuse chromosomal changes related to karyorrhexis and pyknosis are all dependent on considerable synthesis of virus-specific proteins during the middle part of the picornavirus growth cycle. The early virus-induced alterations in cellular biosynthetic processes are not the direct or sole cause of the subsequent marked pathologic changes in the membranes and chromosomes of the cell. Images Figure 1 PMID:1180330

  18. Yellow Fever Virus Infection

    PubMed Central

    David-West, Tam. S.; Smith, J. A.

    1971-01-01

    A sequential and quantitative survey of brain and liver of suckling mice for infective virus and complement-fixing antigen, after infection with yellow fever virus, showed that while there was progressive increase of infective virus content in both organs, only the brain showed a corresponding rise in CF antigen. Histopathological examination revealed that the liver was not significantly involved. The target organ was the brain, where the progressive pathological changes culminated in an acute encephalitis by the 3rd day of experiment. Organ destruction began with the molecular layer of the grey matter. But by the 4th day after infection the entire cerebral cortex was involved. At the initial stages the hippocampus was particularly affected. Tissue damage did not appear to be entirely due to the differential quantitative localization of infective virus. It was hypothesized that the CF antigen acting singly or in conjunction with some hypothetical proteins may be principally involved in the pathological outcome of the disease. ImagesFigs. 7-9Figs. 3-6 PMID:5582071

  19. Virus Chapter: Dicistrovidae

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Dicistroviridae family comprises viruses infecting both beneficial arthropods such as honey bees and shrimp and insect pests of medical and agricultural importance. During the last five years, advances in sequencing and phylogenetic analysis have led to the discovery and identification of sever...

  20. Viruses of haloarchaea.

    PubMed

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

    2014-01-01

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

  1. Varicella zoster virus infection.

    PubMed

    Gershon, Anne A; Breuer, Judith; Cohen, Jeffrey I; Cohrs, Randall J; Gershon, Michael D; Gilden, Don; Grose, Charles; Hambleton, Sophie; Kennedy, Peter G E; Oxman, Michael N; Seward, Jane F; Yamanishi, Koichi

    2015-01-01

    Infection with varicella zoster virus (VZV) causes varicella (chickenpox), which can be severe in immunocompromised individuals, infants and adults. Primary infection is followed by latency in ganglionic neurons. During this period, no virus particles are produced and no obvious neuronal damage occurs. Reactivation of the virus leads to virus replication, which causes zoster (shingles) in tissues innervated by the involved neurons, inflammation and cell death - a process that can lead to persistent radicular pain (postherpetic neuralgia). The pathogenesis of postherpetic neuralgia is unknown and it is difficult to treat. Furthermore, other zoster complications can develop, including myelitis, cranial nerve palsies, meningitis, stroke (vasculopathy), retinitis, and gastroenterological infections such as ulcers, pancreatitis and hepatitis. VZV is the only human herpesvirus for which highly effective vaccines are available. After varicella or vaccination, both wild-type and vaccine-type VZV establish latency, and long-term immunity to varicella develops. However, immunity does not protect against reactivation. Thus, two vaccines are used: one to prevent varicella and one to prevent zoster. In this Primer we discuss the pathogenesis, diagnosis, treatment, and prevention of VZV infections, with an emphasis on the molecular events that regulate these diseases. For an illustrated summary of this Primer, visit: http://go.nature.com/14xVI1. PMID:27188665

  2. Honey Bee Viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Viruses are significant threats to the health and well-being of the honey bee, Apis mellifera. To alleviate the threats posed by these invasive organisms, a better understanding of bee viral infections will be of crucial importance in developing effective and environmentally-benign disease control ...

  3. GENOME OF HORSEPOX VIRUS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Here we present the genomic sequence of horsepox virus (HSPV) isolate MNR-76, an orthopoxvirus (OPV) isolated in 1976 from diseased Mongolian horses. The 212 kbp genome contained 7.5 kbp inverted terminal repeats (ITR) and lacked extensive terminal tandem repetition. HSPV contained 236 ORFs with sim...

  4. A vaccinia virus renaissance

    PubMed Central

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

    2012-01-01

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

  5. Viruses and neurodegeneration

    PubMed Central

    2013-01-01

    Neurodegenerative diseases (NDs) are chronic degenerative diseases of the central nervous system (CNS), which affect 37 million people worldwide. As the lifespan increases, the NDs are the fourth leading cause of death in the developed countries and becoming increasingly prevalent in developing countries. Despite considerable research, the underlying mechanisms remain poorly understood. Although the large majority of studies do not show support for the involvement of pathogenic aetiology in classical NDs, a number of emerging studies show support for possible association of viruses with classical neurodegenerative diseases in humans. Space does not permit for extensive details to be discussed here on non-viral-induced neurodegenerative diseases in humans, as they are well described in literature. Viruses induce alterations and degenerations of neurons both directly and indirectly. Their ability to attack the host immune system, regions of nervous tissue implies that they can interfere with the same pathways involved in classical NDs in humans. Supporting this, many similarities between classical NDs and virus-mediated neurodegeneration (non-classical) have been shown at the anatomic, sub-cellular, genomic and proteomic levels suggesting that viruses can explain neurodegenerative disorders mechanistically. The main objective of this review is to provide readers a detailed snapshot of similarities viral and non-viral neurodegenerative diseases share, so that mechanistic pathways of neurodegeneration in human NDs can be clearly understood. Viruses can guide us to unveil these pathways in human NDs. This will further stimulate the birth of new concepts in the biological research, which is needed for gaining deeper insights into the treatment of human NDs and delineate mechanisms underlying neurodegeneration. PMID:23724961

  6. Western equine encephalitis virus is a recombinant virus.

    PubMed Central

    Hahn, C S; Lustig, S; Strauss, E G; Strauss, J H

    1988-01-01

    The alphaviruses are a group of 26 mosquito-borne viruses that cause a variety of human diseases. Many of the New World alphaviruses cause encephalitis, whereas the Old World viruses more typically cause fever, rash, and arthralgia. The genome is a single-stranded nonsegmented RNA molecule of + polarity; it is about 11,700 nucleotides in length. Several alphavirus genomes have been sequenced in whole or in part, and these sequences demonstrate that alpha-viruses have descended from a common ancestor by divergent evolution. We have now obtained the sequence of the 3'-terminal 4288 nucleotides of the RNA of the New World Alphavirus western equine encephalitis virus (WEEV). Comparisons of the nucleotide and amino acid sequences of WEEV with those of other alphaviruses clearly show that WEEV is recombinant. The sequences of the capsid protein and of the (untranslated) 3'-terminal 80 nucleotides of WEEV are closely related to the corresponding sequences of the New World Alphavirus eastern equine encephalitis virus (EEEV), whereas the sequences of glycoproteins E2 and E1 of WEEV are more closely related to those of an Old World virus, Sindbis virus. Thus, WEEV appears to have arisen by recombination between an EEEV-like virus and a Sindbis-like virus to give rise to a new virus with the encephalogenic properties of EEEV but the antigenic specificity of Sindbis virus. There has been speculation that recombination might play an important role in the evolution of RNA viruses. The current finding that a widespread and successful RNA virus is recombinant provides support for such an hypothesis. Images PMID:3413072

  7. Virus movement within grafted watermelon plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Watermelon production in Florida is impacted by several viruses including whitefly-transmitted Squash vein yellowing virus (SqVYV), Cucurbit yellow stunting disorder virus and Cucurbit leaf crumple virus, and aphid-transmitted Papaya ringspot virus type W (PRSV-W). While germplasm resistant to some...

  8. Single Virus Genomics: A New Tool for Virus Discovery

    PubMed Central

    Allen, Lisa Zeigler; Ishoey, Thomas; Novotny, Mark A.; McLean, Jeffrey S.; Lasken, Roger S.; Williamson, Shannon J.

    2011-01-01

    Whole genome amplification and sequencing of single microbial cells has significantly influenced genomics and microbial ecology by facilitating direct recovery of reference genome data. However, viral genomics continues to suffer due to difficulties related to the isolation and characterization of uncultivated viruses. We report here on a new approach called ‘Single Virus Genomics’, which enabled the isolation and complete genome sequencing of the first single virus particle. A mixed assemblage comprised of two known viruses; E. coli bacteriophages lambda and T4, were sorted using flow cytometric methods and subsequently immobilized in an agarose matrix. Genome amplification was then achieved in situ via multiple displacement amplification (MDA). The complete lambda phage genome was recovered with an average depth of coverage of approximately 437X. The isolation and genome sequencing of uncultivated viruses using Single Virus Genomics approaches will enable researchers to address questions about viral diversity, evolution, adaptation and ecology that were previously unattainable. PMID:21436882

  9. Neuroteratogenic Viruses and Lessons for Zika Virus Models.

    PubMed

    Kim, Kenneth; Shresta, Sujan

    2016-08-01

    The Centers for Disease Control and Prevention has confirmed that Zika virus (ZIKV) causes congenital microcephaly. ZIKV now joins five other neuroteratogenic (NT) viruses in humans and ZIKV research is in its infancy. In addition, there is only one other NT human arbovirus (Venezuelan equine encephalitis virus), which is also poorly understood. But further insight into ZIKV can be found by evaluating arboviruses in domestic animals, of which there are at least seven NT viruses, three of which have been well studied. Here we review two key anatomical structures involved in modeling transplacental NT virus transmission: the placenta and the fetal blood-brain barrier. We then survey major research findings regarding transmission of NT viruses for guidance in establishing a mouse model of Zika disease that is crucial for a better understanding of ZIKV transmission and pathogenesis. PMID:27387029

  10. Detection of sweet potato viruses in Yunnan and genetic diversity analysis of the common viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two hundred seventy-nine samples with virus-like symptoms collected from 16 regions in Yunnan Province were tested by RT-PCR/PCR using virus-specific primers for 8 sweet potato viruses. Six viruses, Sweet potato chlorotic fleck virus (SPCFV), Sweet Potato feathery mottle virus (SPFMV), Sweet potato ...

  11. Mechanisms of Virus Assembly

    PubMed Central

    Perlmutter, Jason D.; Hagan, Michael F.

    2015-01-01

    Viruses are nanoscale entities containing a nucleic acid genome encased in a protein shell called a capsid, and in some cases surrounded by a lipid bilayer membrane. This review summarizes the physics that govern the processes by which capsids assembles within their host cells and in vitro. We describe the thermodynamics and kinetics for assembly of protein subunits into icosahedral capsid shells, and how these are modified in cases where the capsid assembles around a nucleic acid or on a lipid bilayer. We present experimental and theoretical techniques that have been used to characterize capsid assembly, and we highlight aspects of virus assembly which are likely to receive significant attention in the near future. PMID:25532951

  12. [Ebola virus disease: Update].

    PubMed

    de la Calle-Prieto, Fernando; Arsuaga-Vicente, Marta; Mora-Rillo, Marta; Arnalich-Fernandez, Francisco; Arribas, Jose Ramon

    2016-01-01

    The first known Ebola outbreak occurred in 1976. Since then, 24 limited outbreaks had been reported in Central Africa, but never affecting more than 425 persons. The current outbreak in Western Africa is the largest in history with 28,220 reported cases and 11,291 deaths. The magnitude of the epidemic has caused worldwide alarm. For the first time, evacuated patients were treated outside Africa, and secondary cases have occurred in Spain and the United States. Since the start of the current epidemic, our knowledge about the epidemiology, clinical picture, laboratory findings, and virology of Ebola virus disease has considerably expanded. For the first time, experimental treatment has been tried, and there have been spectacular advances in vaccine development. A review is presented of these advances in the knowledge of Ebola virus disease. PMID:26774254

  13. Phage Displayed Peptides to Avian H5N1 Virus Distinguished the Virus from Other Viruses

    PubMed Central

    Qin, Chengfeng; Ren, Xiaofeng

    2011-01-01

    The purpose of the current study was to identify potential ligands and develop a novel diagnostic test to highly pathogenic avian influenza A virus (HPAI), subtype H5N1 viruses using phage display technology. The H5N1 viruses were used as an immobilized target in a biopanning process using a 12-mer phage display random peptide library. After five rounds of panning, three phages expressing peptides HAWDPIPARDPF, AAWHLIVALAPN or ATSHLHVRLPSK had a specific binding activity to H5N1 viruses were isolated. Putative binding motifs to H5N1 viruses were identified by DNA sequencing. In terms of the minimum quantity of viruses, the phage-based ELISA was better than antiserum-based ELISA and a manual, semi-quantitative endpoint RT-PCR for detecting H5N1 viruses. More importantly, the selected phages bearing the specific peptides to H5N1 viruses were capable of differentiating this virus from other avian viruses in enzyme-linked immunosorbent assays. PMID:21887228

  14. Geographic distribution of Bhanja virus.

    PubMed

    Hubálek, Z

    1987-01-01

    A review on the geographic distribution, vectors and hosts of Bhanja virus (Bunyaviridae) is based on reports about: isolations of the virus; antibody surveys. Bhanja virus has been isolated in 15 countries of Asia, Africa and Europe, and antibodies against it have been detected in 15 additional countries. Vector range includes ticks of the family Ixodidae (subfam. Amblyomminae; not subfam. Ixodinae): 13 species of 6 genera (Haemaphysalis, Dermacentor, Hyalomma, Amblyomma, Rhipicephalus and Boophilus) yielded the virus. Bhanja virus has only rarely been isolated from vertebrates (Atelerix, Xerus, Ovis, Bos; possibly bats), though antibodies have been detected frequently in a wide range of mammals (Ruminantia being the major hosts), in several species of birds (Passeriformes, Galliformes) and even reptiles (Ophisaurus apodus). Natural foci of the Bhanja virus infections are of the boskematic type (sensu Rosický), associated closely with pastures of domestic ruminants infested by ticks in the regions of tropical, subtropical and partly temperate climatic zones. PMID:3108117

  15. Principles of Virus Structural Organization

    PubMed Central

    Prasad, B.V. Venkataram; Schmid, Michael F

    2013-01-01

    Viruses, the molecular nanomachines infecting hosts ranging from prokaryotes to eukaryotes, come in different sizes, shapes and symmetries. Questions such as what principles govern their structural organization, what factors guide their assembly, how these viruses integrate multifarious functions into one unique structure have enamored researchers for years. In the last five decades, following Caspar and Klug's elegant conceptualization of how viruses are constructed, high resolution structural studies using X-ray crystallography and more recently cryo-EM techniques have provided a wealth of information on structures of variety of viruses. These studies have significantly furthered our understanding of the principles that underlie structural organization in viruses. Such an understanding has practical impact in providing a rational basis for the design and development of antiviral strategies. In this chapter, we review principles underlying capsid formation in a variety of viruses, emphasizing the recent developments along with some historical perspective. PMID:22297509

  16. Proteorhodopsin genes in giant viruses

    PubMed Central

    2012-01-01

    Viruses with large genomes encode numerous proteins that do not directly participate in virus biogenesis but rather modify key functional systems of infected cells. We report that a distinct group of giant viruses infecting unicellular eukaryotes that includes Organic Lake Phycodnaviruses and Phaeocystis globosa virus encode predicted proteorhodopsins that have not been previously detected in viruses. Search of metagenomic sequence data shows that putative viral proteorhodopsins are extremely abundant in marine environments. Phylogenetic analysis suggests that giant viruses acquired proteorhodopsins via horizontal gene transfer from proteorhodopsin-encoding protists although the actual donor(s) could not be presently identified. The pattern of conservation of the predicted functionally important amino acid residues suggests that viral proteorhodopsin homologs function as sensory rhodopsins. We hypothesize that viral rhodopsins modulate light-dependent signaling, in particular phototaxis, in infected protists. This article was reviewed by Igor B. Zhulin and Laksminarayan M. Iyer. For the full reviews, see the Reviewers’ reports section. PMID:23036091

  17. Cytomegalovirus: the stealth virus.

    PubMed

    Robinson, Sharon

    2016-05-01

    Cytomegalovirus (CMV) is an infection, part of the herpes family of viruses which, if contracted during pregnancy, cancause devastating effects on the newborn baby. This article is written by the trustee of a volunteer-based charity, mostly run by mothers of CMV children, who are striving to raise awareness of this infection, which is more common than Down's syndrome, listeria and toxoplasmosis, and is theprimary preventable cause of childhood hearing loss. PMID:27295757

  18. Hepatitis C Virus.

    PubMed

    Kim, Arthur

    2016-09-01

    This issue provides a clinical overview of hepatitis C virus, focusing on transmission, prevention, screening, diagnosis, evaluation, and treatment. The content of In the Clinic is drawn from the clinical information and education resources of the American College of Physicians (ACP), including MKSAP (Medical Knowledge and Self-Assessment Program). Annals of Internal Medicine editors develop In the Clinic in collaboration with the ACP's Medical Education and Publishing divisions and with the assistance of additional science writers and physician writers. PMID:27595226

  19. Reemergence of Chikungunya Virus

    PubMed Central

    2014-01-01

    Chikungunya virus (CHIKV) is a mosquito-transmitted alphavirus that causes acute fever and acute and chronic musculoskeletal pain in humans. Since 2004, CHIKV has caused millions of cases of disease in the Indian Ocean region and has emerged in new areas, including Europe, the Middle East, and the Pacific region. The mosquito vectors for this virus are globally distributed in tropical and temperate zones, providing the opportunity for CHIKV to continue to expand into new geographic regions. In October 2013, locally acquired cases of CHIKV infection were identified on the Caribbean island of Saint Martin, signaling the arrival of the virus in the Western Hemisphere. In just 9 months, CHIKV has spread to 22 countries in the Caribbean and Central and South America, resulting in hundreds of thousands of cases. CHIKV disease can be highly debilitating, and large epidemics have severe economic consequences. Thus, there is an urgent need for continued research into the epidemiology, pathogenesis, prevention, and treatment of these infections. PMID:25078691

  20. Parainfluenza Virus Infection.

    PubMed

    Branche, Angela R; Falsey, Ann R

    2016-08-01

    Human parainfluenza viruses (HPIVs) are single-stranded, enveloped RNA viruses of the Paramyoviridaie family. There are four serotypes which cause respiratory illnesses in children and adults. HPIVs bind and replicate in the ciliated epithelial cells of the upper and lower respiratory tract and the extent of the infection correlates with the location involved. Seasonal HPIV epidemics result in a significant burden of disease in children and account for 40% of pediatric hospitalizations for lower respiratory tract illnesses (LRTIs) and 75% of croup cases. Parainfluenza viruses are associated with a wide spectrum of illnesses which include otitis media, pharyngitis, conjunctivitis, croup, tracheobronchitis, and pneumonia. Uncommon respiratory manifestations include apnea, bradycardia, parotitis, and respiratory distress syndrome and rarely disseminated infection. Immunity resulting from disease in childhood is incomplete and reinfection with HPIV accounts for 15% of respiratory illnesses in adults. Severe disease and fatal pneumonia may occur in elderly and immunocompromised adults. HPIV pneumonia in recipients of hematopoietic stem cell transplant (HSCT) is associated with 50% acute mortality and 75% mortality at 6 months. Though sensitive molecular diagnostics are available to rapidly diagnose HPIV infection, effective antiviral therapies are not available. Currently, treatment for HPIV infection is supportive with the exception of croup where the use of corticosteroids has been found to be beneficial. Several novel drugs including DAS181 appear promising in efforts to treat severe disease in immunocompromised patients, and vaccines to decrease the burden of disease in young children are in development. PMID:27486735

  1. [Ebola virus disease].

    PubMed

    Karwowska, Kornelia

    2015-01-01

    Ebola virus disease is a zoonosis causing high mortality epidemics in both human and animal populations. The virus belongs to the Filoviride family. It is composed of a single-strand of RNA. Morbidity foci appear in sub-Saharan Africa. The most probable reservoir are fruit bats, which are local delicacy. The most common route of infection is via mucosa or damaged skin. The spread of disease is rapid due to dietary habits, funeral rites and the insufficient supply of disposable equipment in hospitals. The incubation period of the disease ranges from 2 to 21 days. The beginning is abrupt, dominated by influenza-like symptoms. The disease is staggering with the predominant multi-organ failure and shock. Present-day epidemic symptoms from digestive system in the form of vomiting and diarrhoea are dominant. Currently, the research on vaccine and experimental drug is in progress. The virus is damaged by standard disinfectants used in health care units. Epidemic, which broke out in February 2014, caused by the most dangerous type Zaire, is the greatest of the existing. Morbidity and mortality is underestimated due to numerous unreported cases. PMID:25763588

  2. Marek's disease virus morphogenesis.

    PubMed

    Denesvre, Caroline

    2013-06-01

    Marek's disease virus (MDV) is a highly contagious virus that induces T-lymphoma in chicken. This viral infection still circulates in poultry flocks despite the use of vaccines. With the emergence of new virulent strains in the field over time, MDV remains a serious threat to the poultry industry. More than 40 yr after MDV identification as a herpesvirus, the visualization and purification of fully enveloped infectious particles remain a challenge for biologists. The various strategies used to detect such hidden particles by electron microscopy are reviewed herein. It is now generally accepted that the production of cell-free virions only occurs in the feather follicle epithelium and is associated with viral, cellular, or both molecular determinants expressed in this tissue. This tissue is considered the only source of efficient virus shedding into the environment and therefore the origin of successful transmission in birds. In other avian tissues or permissive cell cultures, MDV replication only leads to a very low number of intracellular enveloped virions. In the absence of detectable extracellular enveloped virions in cell culture, the nature of the transmitted infectious material and its mechanisms of spread from cell to cell remain to be deciphered. An attempt is made to bring together the current knowledge on MDV morphogenesis and spread, and new approaches that could help understand MDV morphogenesis are discussed. PMID:23901745

  3. Introducing Virological Concepts Using an Insect Virus.

    ERIC Educational Resources Information Center

    Sheppard, Roger F.

    1980-01-01

    A technique is presented which utilizes wax moth larvae in a laboratory investigation of an insect virus. Describes how an insect virus can be used to introduce undergraduate biology students to laboratory work on viruses and several virological concepts. (SA)

  4. NATIONAL RESPIRATORY AND ENTERIC VIRUS SURVEILLANCE SYSTEM

    EPA Science Inventory

    The National Respiratory and Enteric Virus Surveillance System is a lab based system which monitors temporal and geographic patterns associated with the detection of respiratory syncytial virus (RSV), human parainfluenza viruses (HPIV), respiratory and enteric adenoviruses, and r...

  5. Variant (Swine Origin) Influenza Viruses in Humans

    MedlinePlus

    ... What's this? Submit Button Past Newsletters Variant Influenza Viruses: Background and CDC Risk Assessment and Reporting Language: ... Background CDC Assessment Reporting Background On Variant Influenza Viruses Swine flu viruses do not normally infect humans. ...

  6. Dengue Virus May Bolster Zika's Attack

    MedlinePlus

    ... news/fullstory_159534.html Dengue Virus May Bolster Zika's Attack Prior exposure to this other mosquito-borne ... dengue fever virus may increase the severity of Zika virus, a new study says. Early stage laboratory ...

  7. Selecting Viruses for the Seasonal Influenza Vaccine

    MedlinePlus

    ... which viruses are selected for use in vaccine production? The influenza viruses in the seasonal flu vaccine ... to get a good vaccine virus for vaccine production? There are a number of factors that can ...

  8. Human Immunodeficiency Virus (HIV) Primary Infection

    MedlinePlus

    ... rashes clinical tools newsletter | contact Share | Human Immunodeficiency Virus (HIV) Primary Infection Information for adults A A ... weeks following exposure to HIV (the human immunodeficiency virus). Chronic infection with this virus can cause AIDS ( ...

  9. Epstein-Barr virus antibody test

    MedlinePlus

    Epstein-Barr virus antibody test is a blood test to detect antibodies to the Epstein-Barr virus ( EBV ). ... specialist looks for antibodies to the Epstein-Barr virus. In the first stages of an illness, little ...

  10. Dengue virus growth, purification, and fluorescent labeling.

    PubMed

    Zhang, Summer; Chan, Kuan Rong; Tan, Hwee Cheng; Ooi, Eng Eong

    2014-01-01

    The early events of the dengue virus life cycle involve virus binding, internalization, trafficking, and fusion. Fluorescently labeled viruses can be used to visualize these early processes. As dengue virus has 180 identical copies of the envelope protein attached to the membrane surface and is surrounded by a lipid membrane, amine-reactive (Alexa Fluor) or lipophilic (DiD) dyes can be used for virus labeling. These dyes are highly photostable and are ideal for studies involving cellular uptake and endosomal transport. To improve virus labeling efficiency and minimize the nonspecific labeling of nonviral proteins, virus concentration and purification precede fluorescent labeling of dengue viruses. Besides using these viruses for single-particle tracking, DiD-labeled viruses can also be used to distinguish serotype-specific from cross-neutralizing antibodies. Here the details of virus concentration, purification, virus labeling, applications, and hints of troubleshooting are described. PMID:24696327

  11. Nuclear entry of DNA viruses

    PubMed Central

    Fay, Nikta; Panté, Nelly

    2015-01-01

    DNA viruses undertake their replication within the cell nucleus, and therefore they must first deliver their genome into the nucleus of their host cells. Thus, trafficking across the nuclear envelope is at the basis of DNA virus infections. Nuclear transport of molecules with diameters up to 39 nm is a tightly regulated process that occurs through the nuclear pore complex (NPC). Due to the enormous diversity of virus size and structure, each virus has developed its own strategy for entering the nucleus of their host cells, with no two strategies alike. For example, baculoviruses target their DNA-containing capsid to the NPC and subsequently enter the nucleus intact, while the hepatitis B virus capsid crosses the NPC but disassembles at the nuclear side of the NPC. For other viruses such as herpes simplex virus and adenovirus, although both dock at the NPC, they have each developed a distinct mechanism for the subsequent delivery of their genome into the nucleus. Remarkably, other DNA viruses, such as parvoviruses and human papillomaviruses, access the nucleus through an NPC-independent mechanism. This review discusses our current understanding of the mechanisms used by DNA viruses to deliver their genome into the nucleus, and further presents the experimental evidence for such mechanisms. PMID:26029198

  12. [Bovine immunodeficiency virus: short review].

    PubMed

    Bouillant, A M; Archambault, D

    1990-01-01

    A bovine visna-like virus was isolated by Van Der Maaten et al (1972) but it did not draw attention since, at that time, most efforts were directed towards research on bovine leukemia virus. However, new interest was shown on the bovine visna-like virus after the isolation of the human immunodeficiency virus (HIV), because of the urgent need for developing animal models for the acquired immunodeficiency syndrome (AIDS). The purpose of this paper is to describe the different stages of the identification of the bovine virus and to up-date knowledge about it. The bovine visna-like virus has recently been named the bovine immuno-deficiency-like virus (BIV) and is the sole bovine lentivirus known to-date. BIV shares morphologic, antigenic and genomic characteristics with other lentiviruses. It grows and induces large syncytia in vitro and generates virus-productive and latent infections in cell culture. It causes persistent infection and slow progressive disease in cattle and probably in sheep. As target cells of the virus are leukocytes, the type of which is unknown, perturbations of the immune system are expected. Consequently, BIV may potentiate the occurrence of secondary infections and play a role in retroviral, multiple infections. It is not oncogenic. Transmission appears to occur in cattle by contact, but evidence of transmission in human beings has not been shown. Finally, BIV may be a potential model in vitro and in vivo for HIV and AIDS. PMID:1963056

  13. Emergence of influenza A viruses.

    PubMed Central

    Webby, R J; Webster, R G

    2001-01-01

    Pandemic influenza in humans is a zoonotic disease caused by the transfer of influenza A viruses or virus gene segments from animal reservoirs. Influenza A viruses have been isolated from avian and mammalian hosts, although the primary reservoirs are the aquatic bird populations of the world. In the aquatic birds, influenza is asymptomatic, and the viruses are in evolutionary stasis. The aquatic bird viruses do not replicate well in humans, and these viruses need to reassort or adapt in an intermediate host before they emerge in human populations. Pigs can serve as a host for avian and human viruses and are logical candidates for the role of intermediate host. The transmission of avian H5N1 and H9N2 viruses directly to humans during the late 1990s showed that land-based poultry also can serve between aquatic birds and humans as intermediate hosts of influenza viruses. That these transmission events took place in Hong Kong and China adds further support to the hypothesis that Asia is an epicentre for influenza and stresses the importance of surveillance of pigs and live-bird markets in this area. PMID:11779380

  14. RECOVIR Software for Identifying Viruses

    NASA Technical Reports Server (NTRS)

    Chakravarty, Sugoto; Fox, George E.; Zhu, Dianhui

    2013-01-01

    Most single-stranded RNA (ssRNA) viruses mutate rapidly to generate a large number of strains with highly divergent capsid sequences. Determining the capsid residues or nucleotides that uniquely characterize these strains is critical in understanding the strain diversity of these viruses. RECOVIR (an acronym for "recognize viruses") software predicts the strains of some ssRNA viruses from their limited sequence data. Novel phylogenetic-tree-based databases of protein or nucleic acid residues that uniquely characterize these virus strains are created. Strains of input virus sequences (partial or complete) are predicted through residue-wise comparisons with the databases. RECOVIR uses unique characterizing residues to identify automatically strains of partial or complete capsid sequences of picorna and caliciviruses, two of the most highly diverse ssRNA virus families. Partition-wise comparisons of the database residues with the corresponding residues of more than 300 complete and partial sequences of these viruses resulted in correct strain identification for all of these sequences. This study shows the feasibility of creating databases of hitherto unknown residues uniquely characterizing the capsid sequences of two of the most highly divergent ssRNA virus families. These databases enable automated strain identification from partial or complete capsid sequences of these human and animal pathogens.

  15. Genome of Crocodilepox Virus

    PubMed Central

    Afonso, C. L.; Tulman, E. R.; Delhon, G.; Lu, Z.; Viljoen, G. J.; Wallace, D. B.; Kutish, G. F.; Rock, D. L.

    2006-01-01

    Here, we present the genome sequence, with analysis, of a poxvirus infecting Nile crocodiles (Crocodylus niloticus) (crocodilepox virus; CRV). The genome is 190,054 bp (62% G+C) and predicted to contain 173 genes encoding proteins of 53 to 1,941 amino acids. The central genomic region contains genes conserved and generally colinear with those of other chordopoxviruses (ChPVs). CRV is distinct, as the terminal 33-kbp (left) and 13-kbp (right) genomic regions are largely CRV specific, containing 48 unique genes which lack similarity to other poxvirus genes. Notably, CRV also contains 14 unique genes which disrupt ChPV gene colinearity within the central genomic region, including 7 genes encoding GyrB-like ATPase domains similar to those in cellular type IIA DNA topoisomerases, suggestive of novel ATP-dependent functions. The presence of 10 CRV proteins with similarity to components of cellular multisubunit E3 ubiquitin-protein ligase complexes, including 9 proteins containing F-box motifs and F-box-associated regions and a homologue of cellular anaphase-promoting complex subunit 11 (Apc11), suggests that modification of host ubiquitination pathways may be significant for CRV-host cell interaction. CRV encodes a novel complement of proteins potentially involved in DNA replication, including a NAD+-dependent DNA ligase and a protein with similarity to both vaccinia virus F16L and prokaryotic serine site-specific resolvase-invertases. CRV lacks genes encoding proteins for nucleotide metabolism. CRV shares notable genomic similarities with molluscum contagiosum virus, including genes found only in these two viruses. Phylogenetic analysis indicates that CRV is quite distinct from other ChPVs, representing a new genus within the subfamily Chordopoxvirinae, and it lacks recognizable homologues of most ChPV genes involved in virulence and host range, including those involving interferon response, intracellular signaling, and host immune response modulation. These data reveal

  16. Genome of crocodilepox virus.

    PubMed

    Afonso, C L; Tulman, E R; Delhon, G; Lu, Z; Viljoen, G J; Wallace, D B; Kutish, G F; Rock, D L

    2006-05-01

    Here, we present the genome sequence, with analysis, of a poxvirus infecting Nile crocodiles (Crocodylus niloticus) (crocodilepox virus; CRV). The genome is 190,054 bp (62% G+C) and predicted to contain 173 genes encoding proteins of 53 to 1,941 amino acids. The central genomic region contains genes conserved and generally colinear with those of other chordopoxviruses (ChPVs). CRV is distinct, as the terminal 33-kbp (left) and 13-kbp (right) genomic regions are largely CRV specific, containing 48 unique genes which lack similarity to other poxvirus genes. Notably, CRV also contains 14 unique genes which disrupt ChPV gene colinearity within the central genomic region, including 7 genes encoding GyrB-like ATPase domains similar to those in cellular type IIA DNA topoisomerases, suggestive of novel ATP-dependent functions. The presence of 10 CRV proteins with similarity to components of cellular multisubunit E3 ubiquitin-protein ligase complexes, including 9 proteins containing F-box motifs and F-box-associated regions and a homologue of cellular anaphase-promoting complex subunit 11 (Apc11), suggests that modification of host ubiquitination pathways may be significant for CRV-host cell interaction. CRV encodes a novel complement of proteins potentially involved in DNA replication, including a NAD(+)-dependent DNA ligase and a protein with similarity to both vaccinia virus F16L and prokaryotic serine site-specific resolvase-invertases. CRV lacks genes encoding proteins for nucleotide metabolism. CRV shares notable genomic similarities with molluscum contagiosum virus, including genes found only in these two viruses. Phylogenetic analysis indicates that CRV is quite distinct from other ChPVs, representing a new genus within the subfamily Chordopoxvirinae, and it lacks recognizable homologues of most ChPV genes involved in virulence and host range, including those involving interferon response, intracellular signaling, and host immune response modulation. These data

  17. Structure of Flexible Filamentous Plant Viruses

    SciTech Connect

    Kendall, Amy; McDonald, Michele; Bian, Wen; Bowles, Timothy; Baumgarten, Sarah C.; Shi, Jian; Stewart, Phoebe L.; Bullitt, Esther; Gore, David; Irving, Thomas C.; Havens, Wendy M.; Ghabrial, Said A.; Wall, Joseph S.; Stubbs, Gerald

    2008-10-23

    Flexible filamentous viruses make up a large fraction of the known plant viruses, but in comparison with those of other viruses, very little is known about their structures. We have used fiber diffraction, cryo-electron microscopy, and scanning transmission electron microscopy to determine the symmetry of a potyvirus, soybean mosaic virus; to confirm the symmetry of a potexvirus, potato virus X; and to determine the low-resolution structures of both viruses. We conclude that these viruses and, by implication, most or all flexible filamentous plant viruses share a common coat protein fold and helical symmetry, with slightly less than 9 subunits per helical turn.

  18. Computer virus information update CIAC-2301

    SciTech Connect

    Orvis, W.J.

    1994-01-15

    While CIAC periodically issues bulletins about specific computer viruses, these bulletins do not cover all the computer viruses that affect desktop computers. The purpose of this document is to identify most of the known viruses for the MS-DOS and Macintosh platforms and give an overview of the effects of each virus. The authors also include information on some windows, Atari, and Amiga viruses. This document is revised periodically as new virus information becomes available. This document replaces all earlier versions of the CIAC Computer virus Information Update. The date on the front cover indicates date on which the information in this document was extracted from CIAC`s Virus database.

  19. Zika virus: epidemiology, clinical features and host-virus interactions.

    PubMed

    Hamel, Rodolphe; Liégeois, Florian; Wichit, Sineewanlaya; Pompon, Julien; Diop, Fodé; Talignani, Loïc; Thomas, Frédéric; Desprès, Philippe; Yssel, Hans; Missé, Dorothée

    2016-01-01

    Very recently, Zika virus (ZIKV) has gained a medical importance following the large-scale epidemics in South Pacific and Latin America. This paper reviews information on the epidemiology and clinical features of Zika disease with a particular emphasis on the host-virus interactions that contribute to the pathogenicity of ZIKV in humans. PMID:27012221

  20. Parainfluenza Virus 5 Expressing the G Protein of Rabies Virus Protects Mice after Rabies Virus Infection

    PubMed Central

    Huang, Ying; Chen, Zhenhai; Huang, Junhua

    2014-01-01

    Rabies remains a major public health threat around the world. Once symptoms appear, there is no effective treatment to prevent death. In this work, we tested a recombinant parainfluenza virus 5 (PIV5) strain expressing the glycoprotein (G) of rabies (PIV5-G) as a therapy for rabies virus infection: we have found that PIV5-G protected mice as late as 6 days after rabies virus infection. PIV5-G is a promising vaccine for prevention and treatment of rabies virus infection. PMID:25552723

  1. Uukuniemi Virus as a Tick-Borne Virus Model

    PubMed Central

    Mazelier, Magalie; Rouxel, Ronan Nicolas; Zumstein, Michael; Mancini, Roberta; Bell-Sakyi, Lesley

    2016-01-01

    ABSTRACT In the last decade, novel tick-borne pathogenic phleboviruses in the family Bunyaviridae, all closely related to Uukuniemi virus (UUKV), have emerged on different continents. To reproduce the tick-mammal switch in vitro, we first established a reverse genetics system to rescue UUKV with a genome close to that of the authentic virus isolated from the Ixodes ricinus tick reservoir. The IRE/CTVM19 and IRE/CTVM20 cell lines, both derived from I. ricinus, were susceptible to the virus rescued from plasmid DNAs and supported production of the virus over many weeks, indicating that infection was persistent. The glycoprotein GC was mainly highly mannosylated on tick cell-derived viral progeny. The second envelope viral protein, GN, carried mostly N-glycans not recognized by the classical glycosidases peptide-N-glycosidase F (PNGase F) and endoglycosidase H (Endo H). Treatment with β-mercaptoethanol did not impact the apparent molecular weight of GN. On viruses originating from mammalian BHK-21 cells, GN glycosylations were exclusively sensitive to PNGase F, and the electrophoretic mobility of the protein was substantially slower after the reduction of disulfide bonds. Furthermore, the amount of viral nucleoprotein per focus forming unit differed markedly whether viruses were produced in tick or BHK-21 cells, suggesting a higher infectivity for tick cell-derived viruses. Together, our results indicate that UUKV particles derived from vector tick cells have glycosylation and structural specificities that may influence the initial infection in mammalian hosts. This study also highlights the importance of working with viruses originating from arthropod vector cells in investigations of the cell biology of arbovirus transmission and entry into mammalian hosts. IMPORTANCE Tick-borne phleboviruses represent a growing threat to humans globally. Although ticks are important vectors of infectious emerging diseases, previous studies have mainly involved virus stocks

  2. Virioplankton: Viruses in Aquatic Ecosystems†

    PubMed Central

    Wommack, K. Eric; Colwell, Rita R.

    2000-01-01

    The discovery that viruses may be the most abundant organisms in natural waters, surpassing the number of bacteria by an order of magnitude, has inspired a resurgence of interest in viruses in the aquatic environment. Surprisingly little was known of the interaction of viruses and their hosts in nature. In the decade since the reports of extraordinarily large virus populations were published, enumeration of viruses in aquatic environments has demonstrated that the virioplankton are dynamic components of the plankton, changing dramatically in number with geographical location and season. The evidence to date suggests that virioplankton communities are composed principally of bacteriophages and, to a lesser extent, eukaryotic algal viruses. The influence of viral infection and lysis on bacterial and phytoplankton host communities was measurable after new methods were developed and prior knowledge of bacteriophage biology was incorporated into concepts of parasite and host community interactions. The new methods have yielded data showing that viral infection can have a significant impact on bacteria and unicellular algae populations and supporting the hypothesis that viruses play a significant role in microbial food webs. Besides predation limiting bacteria and phytoplankton populations, the specific nature of virus-host interaction raises the intriguing possibility that viral infection influences the structure and diversity of aquatic microbial communities. Novel applications of molecular genetic techniques have provided good evidence that viral infection can significantly influence the composition and diversity of aquatic microbial communities. PMID:10704475

  3. Pathogenic Pseudorabies Virus, China, 2012

    PubMed Central

    Yu, Xiuling; Zhou, Zhi; Hu, Dongmei; Zhang, Qian; Han, Tao; Li, Xiaoxia; Gu, Xiaoxue; Yuan, Lin; Zhang, Shuo; Wang, Baoyue; Qu, Ping; Liu, Jinhua; Zhai, Xinyan

    2014-01-01

    In 2012, an unprecedented large-scale outbreak of disease in pigs in China caused great economic losses to the swine industry. Isolates from pseudorabies virus epidemics in swine herds were characterized. Evidence confirmed that the pathogenic pseudorabies virus was the etiologic agent of this epidemic. PMID:24377462

  4. Groundnut Ringspot Virus in Florida

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Tospoviruses in vegetable crops are difficult to manage due to a shortage of basic information about the viruses and their vectors. This is especially true for the recently detected Groundnut ringspot virus (GRSV). This publication presents all current knowledge of GRSV in Florida....

  5. TOTAL CULTURABLE VIRUS QUANTAL ASSAY

    EPA Science Inventory

    This chapter describes a quantal method for assaying culturable human enteric viruses from water matrices. The assay differs from the plaque assay described in Chapter 10 (December 1987 Revision) in that it is based upon the direct microscopic viewing of cells for virus-induced ...

  6. Paper Models Illustrating Virus Symmetry.

    ERIC Educational Resources Information Center

    McCarthy, D. A.

    1990-01-01

    Instructions are given for constructing two models, one to illustrate the general principles of symmetry in T=1, T=3, and T=4 viruses, and the other to illustrate the disposition of protein subunits in the T=3 plant viruses and the picornaviruses. (Author/CW)

  7. Tobacco ringspot virus in Rubus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Tobacco ringspot virus (TRSV) has a broad host range among woody and perennial plants and has been reported from blackberry but not from red or black raspberry. The virus has been detected in blackberry in the southeastern United States with a single report from blackberry in British Columbia, Cana...

  8. Oncolytic virus therapy for cancer

    PubMed Central

    Goldufsky, Joe; Sivendran, Shanthi; Harcharik, Sara; Pan, Michael; Bernardo, Sebastian; Stern, Richard H; Friedlander, Philip; Ruby, Carl E; Saenger, Yvonne; Kaufman, Howard L

    2013-01-01

    The use of oncolytic viruses to treat cancer is based on the selection of tropic tumor viruses or the generation of replication selective vectors that can either directly kill infected tumor cells or increase their susceptibility to cell death and apoptosis through additional exposure to radiation or chemotherapy. In addition, viral vectors can be modified to promote more potent tumor cell death, improve the toxicity profile, and/or generate host antitumor immunity. A variety of viruses have been developed as oncolytic therapeutics, including adenovirus, vaccinia virus, herpesvirus, coxsackie A virus, Newcastle disease virus, and reovirus. The clinical development of oncolytic viral therapy has accelerated in the last few years, with several vectors entering clinical trials for a variety of cancers. In this review, current strategies to optimize the therapeutic effectiveness and safety of the major oncolytic viruses are discussed, and a summary of current clinical trials is provided. Further investigation is needed to characterize better the clinical impact of oncolytic viruses, but there are increasing data demonstrating the potential promise of this approach for the treatment of human and animal cancers. PMID:27512656

  9. Unraveling hepatitis C virus structure.

    PubMed

    Fauvelle, Catherine; Felmlee, Daniel J; Baumert, Thomas F

    2014-04-01

    The high variability and the limited knowledge of the structure of the hepatitis C virus (HCV) envelope glycoproteins (GP) are challenging hurdles for vaccine design. Recently, Kong et al. published a new model of HCV E2 GP structure in Science, revealing a globular structure, starkly contrasting from the extended model of class II fusion proteins from other Flaviviridae viruses. PMID:24626133

  10. Genetic Diversity of Toscana Virus

    PubMed Central

    Collao, Ximena; Palacios, Gustavo; Sanbonmatsu-Gámez, Sara; Pérez-Ruiz, Mercedes; Negredo, Ana I.; Navarro-Marí, José-María; Grandadam, Marc; Aransay, Ana Maria; Lipkin, W. Ian; Tenorio, Antonio

    2009-01-01

    Distribution of Toscana virus (TOSV) is evolving with climate change, and pathogenicity may be higher in nonexposed populations outside areas of current prevalence (Mediterranean Basin). To characterize genetic diversity of TOSV, we determined the coding sequences of isolates from Spain and France. TOSV is more diverse than other well-studied phleboviruses (e.g.,Rift Valley fever virus). PMID:19331735

  11. Virus Detection and Field Management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There are two primary pathogens of Oat – Crown Rust and the Luteoviruses Barley and Cereal Yellow Dwarf Virus (BYDV and CYDV). These viruses can only be transmitted by aphids, are limited to the vascular system in infected plants and can lead to severe stunting and a concomitant yield loss. In 200...

  12. Swine Influenza Virus: Emerging Understandings

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Introduction: In March-April 2009, a novel pandemic H1N1 emerged in the human population in North America [1]. The gene constellation of the emerging virus was demonstrated to be a combination of genes from swine influenza A viruses (SIV) of North American and Eurasian lineages that had never before...

  13. Virology of hepatitis C virus.

    PubMed

    Fang, J W; Chow, V; Lau, J Y

    1997-11-01

    Advances in molecular biology techniques have allowed the cloning of HCV and the characterization of this virus. This article provides a short summary of our current knowledge on the genomic organization of HCV, the implications of its genetic heterogeneous nature, and the probable replication strategy of this virus. PMID:15560054

  14. Zika Virus Infection and Microcephaly.

    PubMed

    Millichap, J Gordon

    2016-01-01

    A Task Force established by the Brazil Ministry of Health investigated the possible association of microcephaly with Zika virus infection during pregnancy and a registry for microcephaly cases among women suspected to have had Zika virus infection during pregnancy. PMID:27004142

  15. Antiviral immunity and virus vaccines

    Technology Transfer Automated Retrieval System (TEKTRAN)

    As obligate intracellular organisms, viruses have co-evolved with their respective host species, which in turn have evolved diverse and sophisticated capabilities to protect themselves against viral infections and their associated diseases. Viruses have also evolved a remarkable variety of strategie...

  16. Neonatal herpes simplex virus.

    PubMed

    Berardi, Alberto; Lugli, Licia; Rossi, Cecilia; Maria, Chiara Laguardia; Guidotti, Isotta; Gallo, Claudio; Ferrari, Fabrizio

    2011-10-01

    Herpes simplex virus is an important cause of neonatal infection, which can lead to death or long-term disabilities. Rarely in utero, the transmission frequently occurs during delivery. The disease may be disseminated, localized to the central nervous system, or involving skin, eye and/or mouth. Mortality rates markedly decreased with high-dose antiviral treatment. Diagnosis of neonatal infection is based on viral isolation from ulcerated vesicles or by scarifying mucocutaneous lesions. Recently polymerase chain reaction plays a central role for both viral detection (skin, mucosal, cerebrospinal fluid samples) and response to therapy. Vertical transmission may be decreased by prophylactic antiviral treatment. PMID:21942600

  17. Feline immunodeficiency virus infection.

    PubMed

    Pedersen, N C; Yamamoto, J K; Ishida, T; Hansen, H

    1989-05-01

    Feline immunodeficiency virus (FIV) (formerly feline T-lymphotropic lentivirus or FTLV) was first isolated from a group of cats in Petaluma, California in 1986. The virus is a typical lentivirus in gross and structural morphology. It replicates preferentially but not exclusively in feline T-lymphoblastoid cells, where it causes a characteristic cytopathic effect. The major structural proteins are 10, 17 (small gag), 28 (major core), 31 (endonuclease?), 41 (transmembrane?), 52 (core precursor polyprotein), 54/62 (reverse transcriptase?), and 110/130 (major envelope) kilodaltons in size. The various proteins are antigenically distinguishable from those of other lentiviruses, although serum from EIAV-infected horses will cross-react with some FIV antigens. Kittens experimentally infected with FIV manifest a transient (several days to 2 weeks) fever and neutropenia beginning 4 to 8 weeks after inoculation. This is associated with a generalized lymphadenopathy that persists for up to 9 months. Most cats recover from this initial phase of the disease and become lifelong carriers of the virus. Complete recovery does not occur to any extent in nature or in the laboratory setting. One experimentally infected cat died from a myeloproliferative disorder several months after infection. The terminal AIDS-like phase of the illness has been seen mainly in naturally infected cats. It appears a year or more following the initial infection in an unknown proportion of infected animals. FIV has been identified in cats from all parts of the world. It is most prevalent in high density populations of free roaming cats (feral and pet), and is very uncommon in closed purebred catteries. Male cats are twice as likely to become infected as females. Older male cats adopted as feral or stray animals are at the highest risk of infection, therefore. The infection rate among freely roaming cats rises throughout life, and reaches levels ranging from less than 1% to 12% or more depending on the

  18. Sunshine virus in Australian pythons.

    PubMed

    Hyndman, Timothy H; Shilton, Cathy M; Doneley, Robert J T; Nicholls, Philip K

    2012-12-28

    Sunshine virus is a recently discovered novel paramyxovirus that is associated with illness in snakes. It does not phylogenetically cluster within either of the two currently accepted paramyxoviral subfamilies. It is therefore only distantly related to the only other known genus of reptilian paramyxoviruses, Ferlavirus, which clusters within the Paramyxovirinae subfamily. Clinical and diagnostic aspects associated with Sunshine virus are as yet undescribed. The objective of this paper was to report the clinical presentation, virus isolation, PCR testing and pathology associated with Sunshine virus infection. Clinical records and samples from naturally occurring cases were obtained from two captive snake collections and the archives of a veterinary diagnostic laboratory. The clinical signs that are associated with Sunshine virus infection are localised to the neurorespiratory systems or are non-specific (e.g. lethargy, inappetence). Out of 15 snakes that were infected with Sunshine virus (detected in any organ by either virus isolation or PCR), the virus was isolated from four out of ten (4/10) sampled brains, 3/10 sampled lungs and 2/7 pooled samples of kidney and liver. In these same 15 snakes, PCR was able to successfully detect Sunshine virus in fresh-frozen brain (11/11), kidney (7/8), lung (8/11) and liver (5/8); and various formalin-fixed paraffin-embedded tissues (7/8). During a natural outbreak of Sunshine virus in a collection of 32 snakes, the virus could be detected in five out of 39 combined oral-cloacal swabs that were collected from 23 of these snakes over a 105 day period. All snakes that were infected with Sunshine virus were negative for reovirus and ferlavirus by PCR. Snakes infected with Sunshine virus reliably exhibited hindbrain white matter spongiosis and gliosis with extension to the surrounding grey matter and neuronal necrosis evident in severe cases. Five out of eight infected snakes also exhibited mild bronchointerstitial pneumonia

  19. New aspects of influenza viruses.

    PubMed Central

    Shaw, M W; Arden, N H; Maassab, H F

    1992-01-01

    Influenza virus infections continue to cause substantial morbidity and mortality with a worldwide social and economic impact. The past five years have seen dramatic advances in our understanding of viral replication, evolution, and antigenic variation. Genetic analyses have clarified relationships between human and animal influenza virus strains, demonstrating the potential for the appearance of new pandemic reassortants as hemagglutinin and neuraminidase genes are exchanged in an intermediate host. Clinical trials of candidate live attenuated influenza virus vaccines have shown the cold-adapted reassortants to be a promising alternative to the currently available inactivated virus preparations. Modern molecular techniques have allowed serious consideration of new approaches to the development of antiviral agents and vaccines as the functions of the viral genes and proteins are further elucidated. The development of techniques whereby the genes of influenza viruses can be specifically altered to investigate those functions will undoubtedly accelerate the pace at which our knowledge expands. PMID:1310439

  20. Virus assembly, allostery, and antivirals

    PubMed Central

    Zlotnick, Adam; Mukhopadhyay, Suchetana

    2010-01-01

    Assembly of virus capsids and surface proteins must be regulated to ensure that the resulting complex is an infectious virion. Here we examine assembly of virus capsids, focusing on hepatitis B virus and bacteriophage MS2, and formation of glycoproteins in the alphaviruses. These systems are structurally and biochemically well-characterized and are simplest-case paradigms of self-assembly. Published data suggest that capsid and glycoprotein assembly is subject to allosteric regulation, that is, regulation at the level of conformational change. The hypothesis that allostery is a common theme in viruses suggests that deregulation of capsid and glycoprotein assembly by small molecule effectors will be an attractive antiviral strategy, as has been demonstrated with hepatitis B virus. PMID:21163649

  1. Marine Viruses: Truth or Dare

    NASA Astrophysics Data System (ADS)

    Breitbart, Mya

    2012-01-01

    Over the past two decades, marine virology has progressed from a curiosity to an intensely studied topic of critical importance to oceanography. At concentrations of approximately 10 million viruses per milliliter of surface seawater, viruses are the most abundant biological entities in the oceans. The majority of these viruses are phages (viruses that infect bacteria). Through lysing their bacterial hosts, marine phages control bacterial abundance, affect community composition, and impact global biogeochemical cycles. In addition, phages influence their hosts through selection for resistance, horizontal gene transfer, and manipulation of bacterial metabolism. Recent work has also demonstrated that marine phages are extremely diverse and can carry a variety of auxiliary metabolic genes encoding critical ecological functions. This review is structured as a scientific "truth or dare," revealing several well-established "truths" about marine viruses and presenting a few "dares" for the research community to undertake in future studies.

  2. Giant viruses come of age.

    PubMed

    Fischer, Matthias G

    2016-06-01

    Viruses with genomes up to a few megabases in length are a common occurrence in nature, even though they have escaped our notice until recently. These giant viruses infect mainly single-celled eukaryotes and isolation efforts concentrating on amoebal hosts alone have spawned hundreds of viral isolates, featuring viruses with previously unseen virion morphologies and the largest known viral genomes and particles. One of the challenges that lie ahead is to analyze and categorize the available data and to establish an approved classification system that reflects the evolutionary relationships and biological properties of these viruses. Extensive sampling of Acanthamoeba-infecting mimiviruses and initial characterization of their virophage parasites have provided a first blueprint of the genetic diversity and composition of a giant virus clade that will facilitate the taxonomic grouping of these fascinating microorganisms. PMID:26999382

  3. Sequence heterogeneity of murine acquired immunodeficiency syndrome virus: the role of endogenous virus.

    PubMed

    Gayama, S; Vaupel, B A; Kanagawa, O

    1995-05-01

    A defective murine leukemia virus is the causative agent of murine acquired immunodeficiency syndrome (MAIDS). We have cloned cDNAs from both virus infected and non-infected cells using the PCR methods with primers corresponding to the franking sequence of the unique p12 gag gene. Sequence analysis of these cDNA clones revealed: (i) the presence of endogenous virus related to MAIDS virus in C57BL/6 mice, (ii) B cell lineage specific expression of endogenous virus and (iii) extensive heterogeneity of MAIDS virus recovered from virus infected cells due to the recombination of the related viruses (defective pathogenic virus, ecotropic virus and endogenous virus). These findings suggest that the creation of virus variants in infected cells may play an important role in virus pathogenesis and escape from immune attack during the development of MAIDS. PMID:7547712

  4. Dengue virus vaccine development.

    PubMed

    Yauch, Lauren E; Shresta, Sujan

    2014-01-01

    Dengue virus (DENV) is a significant cause of morbidity and mortality in tropical and subtropical regions, causing hundreds of millions of infections each year. Infections range from asymptomatic to a self-limited febrile illness, dengue fever (DF), to the life-threatening dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS). The expanding of the habitat of DENV-transmitting mosquitoes has resulted in dramatic increases in the number of cases over the past 50 years, and recent outbreaks have occurred in the United States. Developing a dengue vaccine is a global health priority. DENV vaccine development is challenging due to the existence of four serotypes of the virus (DENV1-4), which a vaccine must protect against. Additionally, the adaptive immune response to DENV may be both protective and pathogenic upon subsequent infection, and the precise features of protective versus pathogenic immune responses to DENV are unknown, complicating vaccine development. Numerous vaccine candidates, including live attenuated, inactivated, recombinant subunit, DNA, and viral vectored vaccines, are in various stages of clinical development, from preclinical to phase 3. This review will discuss the adaptive immune response to DENV, dengue vaccine challenges, animal models used to test dengue vaccine candidates, and historical and current dengue vaccine approaches. PMID:24373316

  5. Hepatitis E Virus Infection

    PubMed Central

    Dalton, Harry R.; Abravanel, Florence; Izopet, Jacques

    2014-01-01

    SUMMARY Hepatitis E virus (HEV) infection is a worldwide disease. An improved understanding of the natural history of HEV infection has been achieved within the last decade. Several reservoirs and transmission modes have been identified. Hepatitis E is an underdiagnosed disease, in part due to the use of serological assays with low sensitivity. However, diagnostic tools, including nucleic acid-based tests, have been improved. The epidemiology and clinical features of hepatitis E differ between developing and developed countries. HEV infection is usually an acute self-limiting disease, but in developed countries it causes chronic infection with rapidly progressive cirrhosis in organ transplant recipients, patients with hematological malignancy requiring chemotherapy, and individuals with HIV. HEV also causes extrahepatic manifestations, including a number of neurological syndromes and renal injury. Acute infection usually requires no treatment, but chronic infection should be treated by reducing immunosuppression in transplant patients and/or the use of antiviral therapy. In this comprehensive review, we summarize the current knowledge about the virus itself, as well as the epidemiology, diagnostics, natural history, and management of HEV infection in developing and developed countries. PMID:24396139

  6. APOBECs and Virus Restriction

    PubMed Central

    Harris, Reuben S.; Dudley, Jaquelin P.

    2015-01-01

    The APOBEC family of single-stranded DNA cytosine deaminases comprises a formidable arm of the vertebrate innate immune system. Pre-vertebrates express a single APOBEC, whereas some mammals produce as many as eleven enzymes. The APOBEC3 subfamily displays both copy number variation and polymorphisms, consistent with ongoing pathogenic pressures. These enzymes restrict the replication of many DNA-based parasites, such as exogenous viruses and endogenous transposable elements. APOBEC1 and activation-induced cytosine deaminase (AID) have specialized functions in RNA editing and antibody gene diversification, respectively, whereas APOBEC2 and APOBEC4 appear to have different functions. Nevertheless, the APOBEC family protects against both periodic viral zoonoses as well as exogenous and endogenous parasite replication. This review highlights viral pathogens that are restricted by APOBEC enzymes, but manage to escape through unique mechanisms. The sensitivity of viruses that lack counterdefense measures highlights the need to develop APOBEC-enabling small molecules as a new class of anti-viral drugs. PMID:25818029

  7. Comparison of Immunohistochemistry and Virus Isolation for Diagnosis of West Nile Virus

    PubMed Central

    Ellis, Angela E.; Mead, Daniel G.; Allison, Andrew B.; Gibbs, Samantha E. J.; Gottdenker, Nicole L.; Stallknecht, David E.; Howerth, Elizabeth W.

    2005-01-01

    Immunohistochemistry and virus isolation were performed on 1,057 birds. Immunohistochemistry, virus isolation, or both found 325 birds to be West Nile virus positive. Of these, 271 were positive by both methods. These results indicate that virus isolation and immunohistochemistry are approximately equal in their ability to detect West Nile virus. PMID:15956415

  8. A single vertebrate DNA virus protein disarms invertebrate immunity to RNA virus infection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Virus-host interactions drive a remarkable diversity of immune responses and countermeasures. While investigating virus-invertebrate host interactions we found that two RNA viruses with broad host ranges, vesicular stomatitis virus (VSV) and Sindbis virus (SINV), were unable to infect certain Lepido...

  9. Infectious vaccinia virus recombinants that express hepatitis B virus surface antigen

    NASA Astrophysics Data System (ADS)

    Smith, Geoffrey L.; Mackett, Michael; Moss, Bernard

    1983-04-01

    Potential live vaccines against hepatitis B virus have been produced. The coding sequence for hepatitis B virus surface antigen (HBsAg) has been inserted into the vaccinia virus genome under control of vaccinia virus early promoters. Cells infected with these vaccinia virus recombinants synthesize and excrete HBsAg and vaccinated rabbits rapidly produce antibodies to HBsAg.

  10. Live-attenuated influenza A virus vaccines using a B virus backbone

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The currently FDA-licensed live attenuated influenza virus vaccine contains a trivalent mixture of types A (H1N1 and H3N2) and B vaccine viruses. The two A virus vaccines have the backbone of a cold-adapted influenza A virus and the B virus vaccine has the six backbone segments derived from a cold-...

  11. Safe Computing: An Overview of Viruses.

    ERIC Educational Resources Information Center

    Wodarz, Nan

    2001-01-01

    A computer virus is a program that replicates itself, in conjunction with an additional program that can harm a computer system. Common viruses include boot-sector, macro, companion, overwriting, and multipartite. Viruses can be fast, slow, stealthy, and polymorphic. Anti-virus products are described. (MLH)

  12. The IFITMs Inhibit Zika Virus Replication.

    PubMed

    Savidis, George; Perreira, Jill M; Portmann, Jocelyn M; Meraner, Paul; Guo, Zhiru; Green, Sharone; Brass, Abraham L

    2016-06-14

    Zika virus has emerged as a severe health threat with a rapidly expanding range. The IFITM family of restriction factors inhibits the replication of a broad range of viruses, including the closely related flaviruses West Nile virus and dengue virus. Here, we show that IFITM1 and IFITM3 inhibit Zika virus infection early in the viral life cycle. Moreover, IFITM3 can prevent Zika-virus-induced cell death. These results suggest that strategies to boost the actions and/or levels of the IFITMs might be useful for inhibiting a broad range of emerging viruses. PMID:27268505

  13. Defining Life: The Virus Viewpoint

    NASA Astrophysics Data System (ADS)

    Forterre, Patrick

    2010-04-01

    Are viruses alive? Until very recently, answering this question was often negative and viruses were not considered in discussions on the origin and definition of life. This situation is rapidly changing, following several discoveries that have modified our vision of viruses. It has been recognized that viruses have played (and still play) a major innovative role in the evolution of cellular organisms. New definitions of viruses have been proposed and their position in the universal tree of life is actively discussed. Viruses are no more confused with their virions, but can be viewed as complex living entities that transform the infected cell into a novel organism—the virus—producing virions. I suggest here to define life (an historical process) as the mode of existence of ribosome encoding organisms (cells) and capsid encoding organisms (viruses) and their ancestors. I propose to define an organism as an ensemble of integrated organs (molecular or cellular) producing individuals evolving through natural selection. The origin of life on our planet would correspond to the establishment of the first organism corresponding to this definition.

  14. Marburg Virus Reverse Genetics Systems

    PubMed Central

    Schmidt, Kristina Maria; Mühlberger, Elke

    2016-01-01

    The highly pathogenic Marburg virus (MARV) is a member of the Filoviridae family and belongs to the group of nonsegmented negative-strand RNA viruses. Reverse genetics systems established for MARV have been used to study various aspects of the viral replication cycle, analyze host responses, image viral infection, and screen for antivirals. This article provides an overview of the currently established MARV reverse genetic systems based on minigenomes, infectious virus-like particles and full-length clones, and the research that has been conducted using these systems. PMID:27338448

  15. Hepatitis C virus. A review.

    PubMed Central

    Tang, E.

    1991-01-01

    Hepatitis C virus has been shown to be responsible for most cases of posttransfusion hepatitis, as well as for sporadic non-A, non-B viral hepatitis. Hepatitis C virus has also been implicated in the development of primary hepatocellular carcinoma, autoimmune hepatitis, and fulminant viral hepatitis. Although the role of the parenteral transmission of hepatitis C virus is well established, its route of transmission in cases of sporadic infection remains unclear. Sexual transmission is suspected but not confirmed. Recent work regarding treatment has shown interferon alfa to be effective, but the discontinuation of therapy is associated with a 50% relapse rate. PMID:1656611

  16. Marburg Virus Reverse Genetics Systems.

    PubMed

    Schmidt, Kristina Maria; Mühlberger, Elke

    2016-01-01

    The highly pathogenic Marburg virus (MARV) is a member of the Filoviridae family and belongs to the group of nonsegmented negative-strand RNA viruses. Reverse genetics systems established for MARV have been used to study various aspects of the viral replication cycle, analyze host responses, image viral infection, and screen for antivirals. This article provides an overview of the currently established MARV reverse genetic systems based on minigenomes, infectious virus-like particles and full-length clones, and the research that has been conducted using these systems. PMID:27338448

  17. Polymerase Activity of Pichinde Virus

    PubMed Central

    Carter, Michael F.; Biswal, Nilambar; Rawls, William E.

    1974-01-01

    Pichinde virus, a member of the arenavirus group, was examined for polymerase activity. Purified virus was found to contain RNA-dependent RNA polymerase but not RNA-dependent DNA polymerase activity. Since RNase but neither DNase nor actinomycin D inhibited the endogenous polymerase reaction, RNA of the virus appeared to be used as the template. The divalent cations Mg2+ and Mn2+ were required for optimal reactivity. The RNA product was partially resistant to RNase and the resistant portion had a sedimentation coefficient of 22 to 26S in sucrose gradients. PMID:4132669

  18. Xenotropic Murine Leukemia Virus-related Virus (XMRV) Backgrounder

    Cancer.gov

    Researchers have not found evidence that XMRV causes any diseases in humans or in animals. The presence of an infectious agent, such as a virus, in diseased tissue does not mean that the agent causes the disease.

  19. Respiratory Viruses Other than Influenza Virus: Impact and Therapeutic Advances

    PubMed Central

    Nichols, W. Garrett; Peck Campbell, Angela J.; Boeckh, Michael

    2008-01-01

    Summary: Though several antivirals have been developed and marketed to treat influenza virus infections, the development of antiviral agents with clinical activity against other respiratory viruses has been more problematic. Here we review the epidemiology of respiratory viral infections in immunocompetent and immunocompromised hosts, examine the evidence surrounding the currently available antivirals for respiratory viral infections other than influenza, highlight those that are in the pipeline, and discuss the hurdles for development of such agents. PMID:18400797

  20. Human immunodeficiency virus endocrinopathy

    PubMed Central

    Sinha, Uma; Sengupta, Nilanjan; Mukhopadhyay, Prasanta; Roy, Keshab Sinha

    2011-01-01

    Human immunodeficiency virus (HIV) endocrinopathy encompasses a broad spectrum of disorders. Almost all the endocrine organs are virtually affected by HIV infection. HIV can directly alter glandular function. More commonly secondary endocrine dysfunction occurs due to opportunistic infections and neoplasms in immunocompromised state. The complex interaction between HIV infection and endocrine system may be manifested as subtle biochemical and hormonal perturbation to overt glandular failure. Antiretroviral therapy as well as other essential medications often result in adverse endocrinal consequences. Apart from adrenal insufficiency, hypogonadism, diabetes and bone loss, AIDS wasting syndrome and HIV lipodystrophy need special reference. Endocrinal evaluation should proceed as in other patients with suspected endocrine dysfunction. Available treatment options have been shown to improve quality of life and long-term mortality in AIDS patients. PMID:22028995

  1. Zika virus infections.

    PubMed

    de Laval, F; Leparc-Goffart, I; Meynard, J-B; Daubigny, H; Simon, F; Briolant, S

    2016-05-01

    Since its discovery in 1947 in Uganda, the Zika virus (ZIKV) remained in the shadows emerging in 2007 in Micronesia, where hundreds of dengue-like syndromes were reported. Then, in 2013-2014, it was rife in French Polynesia, where the first neurological effects were observed. More recently, its arrival in Brazil was accompanied by an unusually high number of children with microcephaly born to mothers infected with ZIKV during the first trimester of pregnancy. In 2016, the World Health Organization declared ZIKV infection to be a public health emergency and now talks about a ZIKV pandemic. This review aims to summarize the current knowledge about ZIKV infection, successively addressing its transmission, epidemiology, clinical aspects, diagnosis, treatment, and prevention before discussing some perspectives. PMID:27412976

  2. Varicella-zoster virus.

    PubMed Central

    Arvin, A M

    1996-01-01

    Varicella-zoster virus (VZV) is a ubiquitous human alphaherpesvirus that causes varicella (chicken pox) and herpes zoster (shingles). Varicella is a common childhood illness, characterized by fever, viremia, and scattered vesicular lesions of the skin. As is characteristic of the alphaherpesviruses, VZV establishes latency in cells of the dorsal root ganglia. Herpes zoster, caused by VZV reactivation, is a localized, painful, vesicular rash involving one or adjacent dermatomes. The incidence of herpes zoster increases with age or immunosuppression. The VZV virion consists of a nucleocapsid surrounding a core that contains the linear, double-stranded DNA genome; a protein tegument separates the capsid from the lipid envelope, which incorporates the major viral glycoproteins. VZV is found in a worldwide geographic distribution but is more prevalent in temperate climates. Primary VZV infection elicits immunoglobulin G (IgG), IgM, and IgA antibodies, which bind to many classes of viral proteins. Virus-specific cellular immunity is critical for controlling viral replication in healthy and immunocompromised patients with primary or recurrent VZV infections. Rapid laboratory confirmation of the diagnosis of varicella or herpes zoster, which can be accomplished by detecting viral proteins or DNA, is important to determine the need for antiviral therapy. Acyclovir is licensed for treatment of varicella and herpes zoster, and acyclovir, valacyclovir, and famciclovir are approved for herpes zoster. Passive antibody prophylaxis with varicella-zoster immune globulin is indicated for susceptible high-risk patients exposed to varicella. A live attenuated varicella vaccine (Oka/Merck strain) is now recommended for routine childhood immunization. PMID:8809466

  3. Novel vaccines against influenza viruses

    PubMed Central

    Kang, Sang-Moo; Song, Jae-Min; Compans, Richard W.

    2011-01-01

    Killed and live attenuated influenza virus vaccines are effective in preventing and curbing the spread of influenza epidemics when the strains present in the vaccines are closely matched with the predicted epidemic strains. These vaccines are primarily targeted to induce immunity to the variable major target antigen, hemagglutinin (HA) of influenza virus. However, current vaccines are not effective in preventing the emergence of new pandemic or highly virulent viruses. New approaches are being investigated to develop universal influenza virus vaccines as well as to apply more effective vaccine delivery methods. Conserved vaccine targets including the influenza M2 ion channel protein and HA stalk domains are being developed using recombinant technologies to improve the level of cross protection. In addition, recent studies provide evidence that vaccine supplements can provide avenues to further improve current vaccination. PMID:21968298

  4. About Human Parainfluenza Viruses (HPIVs)

    MedlinePlus

    ... Overview Laboratory Diagnosis HPIV Seasons Resources & References About Human Parainfluenza Viruses (HPIVs) Recommend on Facebook Tweet Share ... 6348 Email CDC-INFO U.S. Department of Health & Human Services HHS/Open USA.gov Top

  5. Herpes Simplex Virus (Cold Sores)

    MedlinePlus

    ... the skin, eyes, and mouth. This is a life-threatening infection that can lead to permanent brain damage or even death. Herpes simplex viruses also cause encephalitis, an infection of the brain. ...

  6. Peste des Petits Ruminants Virus.

    PubMed

    Baron, M D; Diallo, A; Lancelot, R; Libeau, G

    2016-01-01

    Peste des petits ruminants virus (PPRV) causes a severe contagious disease of sheep and goats and has spread extensively through the developing world. Because of its disproportionately large impact on the livelihoods of low-income livestock keepers, and the availability of effective vaccines and good diagnostics, the virus is being targeted for global control and eventual eradication. In this review we examine the origin of the virus and its current distribution, and the factors that have led international organizations to conclude that it is eradicable. We also review recent progress in the molecular and cellular biology of the virus and consider areas where further research is required to support the efforts being made by national, regional, and international bodies to tackle this growing threat. PMID:27112279

  7. Viruses of eukaryotice green algae

    SciTech Connect

    Van Etten, J.L.

    1989-01-01

    The primary objective of our research was to develop the Chlorella-PBCV-1 virus system so that it can be used as a model system for studying gene expression in a photosynthetic eukaryote. We have made considerable progress and have learned much about PBCV-1 and its replication cycle. In addition, several significant discoveries were made in the last 3 to 4 years. These discoveries include: (i) the finding that morphologically similar, plaque forming, dsDNA containing viruses are common in nature and can be isolated readily from fresh water, (ii) the finding that all of these Chlorella viruses contain methylated bases which range in concentration from 0.1% to 47.5% m{sup 5}dC and 0 to 37% m{sup 6}dA and (iii) the discovery that infection with at least some of these viruses induces the appearance of DNA modification/restriction systems. 26 refs.

  8. Lactate dehydrogenase-elevating virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This book chapter describes the taxonomic classification of Lactate dehydrogenase-elevating virus (LDV). Included are: host, genome, classification, morphology, physicochemical and physical properties, nucleic acid, proteins, lipids, carbohydrates, geographic range, phylogenetic properties, biologic...

  9. Genetic screen of a library of chimeric poxviruses identifies an ankyrin repeat protein involved in resistance to the avian type I interferon response.

    PubMed

    Buttigieg, Karen; Laidlaw, Stephen M; Ross, Craig; Davies, Marc; Goodbourn, Stephen; Skinner, Michael A

    2013-05-01

    Viruses must be able to resist host innate responses, especially the type I interferon (IFN) response. They do so by preventing the induction or activity of IFN and/or by resisting the antiviral effectors that it induces. Poxviruses are no exception, with many mechanisms identified whereby mammalian poxviruses, notably, vaccinia virus (VACV), but also cowpox and myxoma viruses, are able to evade host IFN responses. Similar mechanisms have not been described for avian poxviruses (avipoxviruses). Restricted for permissive replication to avian hosts, they have received less attention; moreover, the avian host responses are less well characterized. We show that the prototypic avipoxvirus, fowlpox virus (FWPV), is highly resistant to the antiviral effects of avian IFN. A gain-of-function genetic screen identified fpv014 to contribute to increased resistance to exogenous recombinant chicken alpha IFN (ChIFN1). fpv014 is a member of the large family of poxvirus (especially avipoxvirus) genes that encode proteins containing N-terminal ankyrin repeats (ANKs) and C-terminal F-box-like motifs. By binding the Skp1/cullin-1 complex, the F box in such proteins appears to target ligands bound by the ANKs for ubiquitination. Mass spectrometry and immunoblotting demonstrated that tandem affinity-purified, tagged fpv014 was complexed with chicken cullin-1 and Skp1. Prior infection with an fpv014-knockout mutant of FWPV still blocked transfected poly(I·C)-mediated induction of the beta IFN (ChIFN2) promoter as effectively as parental FWPV, but the mutant was more sensitive to exogenous ChIFN1. Therefore, unlike the related protein fpv012, fpv014 does not contribute to the FWPV block to induction of ChIFN2 but does confer resistance to an established antiviral state. PMID:23427151

  10. Genetic Screen of a Library of Chimeric Poxviruses Identifies an Ankyrin Repeat Protein Involved in Resistance to the Avian Type I Interferon Response

    PubMed Central

    Buttigieg, Karen; Laidlaw, Stephen M.; Ross, Craig; Davies, Marc; Goodbourn, Stephen

    2013-01-01

    Viruses must be able to resist host innate responses, especially the type I interferon (IFN) response. They do so by preventing the induction or activity of IFN and/or by resisting the antiviral effectors that it induces. Poxviruses are no exception, with many mechanisms identified whereby mammalian poxviruses, notably, vaccinia virus (VACV), but also cowpox and myxoma viruses, are able to evade host IFN responses. Similar mechanisms have not been described for avian poxviruses (avipoxviruses). Restricted for permissive replication to avian hosts, they have received less attention; moreover, the avian host responses are less well characterized. We show that the prototypic avipoxvirus, fowlpox virus (FWPV), is highly resistant to the antiviral effects of avian IFN. A gain-of-function genetic screen identified fpv014 to contribute to increased resistance to exogenous recombinant chicken alpha IFN (ChIFN1). fpv014 is a member of the large family of poxvirus (especially avipoxvirus) genes that encode proteins containing N-terminal ankyrin repeats (ANKs) and C-terminal F-box-like motifs. By binding the Skp1/cullin-1 complex, the F box in such proteins appears to target ligands bound by the ANKs for ubiquitination. Mass spectrometry and immunoblotting demonstrated that tandem affinity-purified, tagged fpv014 was complexed with chicken cullin-1 and Skp1. Prior infection with an fpv014-knockout mutant of FWPV still blocked transfected poly(I·C)-mediated induction of the beta IFN (ChIFN2) promoter as effectively as parental FWPV, but the mutant was more sensitive to exogenous ChIFN1. Therefore, unlike the related protein fpv012, fpv014 does not contribute to the FWPV block to induction of ChIFN2 but does confer resistance to an established antiviral state. PMID:23427151

  11. Live viruses to treat cancer

    PubMed Central

    Donnelly, Oliver; Harrington, Kevin; Melcher, Alan; Pandha, Hardev

    2013-01-01

    Viruses that selectively replicate in cancer cells, leading to the death of the cell, are being studied for their potential as cancer therapies. Some of these viruses are naturally occurring but cause little if any illness in humans; others have been engineered to make them specifically able to kill cancer cells while sparing normal cells. These oncolytic viruses may be selective for cancer cells because viral receptors are over-expressed on the surface of cancer cells or because antiviral pathways are distorted in cancer cells. Additionally, when oncolytic viruses kill cancer cells, it can stimulate an antitumour immune response from the host that can enhance efficacy. Numerous early phase trials of at least six oncolytic viruses have been reported with no evidence of concerning toxicity either as single agents or in combination with chemotherapies and radiotherapy. Three oncolytic viruses have reached randomized testing in cancer patients; reolysin in head and neck cancer and JX594 in hepatocellular cancers, while results from the first-phase III trial of T-vec in metastatic melanoma are expected shortly. PMID:23824333

  12. A DNA Virus of Drosophila

    PubMed Central

    Unckless, Robert L.

    2011-01-01

    Little is known about the viruses infecting most species. Even in groups as well-studied as Drosophila, only a handful of viruses have been well-characterized. A viral metagenomic approach was used to explore viral diversity in 83 wild-caught Drosophila innubila, a mushroom feeding member of the quinaria group. A single fly that was injected with, and died from, Drosophila C Virus (DCV) was added to the sample as a control. Two-thirds of reads in the infected sample had DCV as the best BLAST hit, suggesting that the protocol developed is highly sensitive. In addition to the DCV hits, several sequences had Oryctes rhinoceros Nudivirus, a double-stranded DNA virus, as a best BLAST hit. The virus associated with these sequences was termed Drosophila innubila Nudivirus (DiNV). PCR screens of natural populations showed that DiNV was both common and widespread taxonomically and geographically. Electron microscopy confirms the presence of virions in fly fecal material similar in structure to other described Nudiviruses. In 2 species, D. innubila and D. falleni, the virus is associated with a severe (∼80–90%) loss of fecundity and significantly decreased lifespan. PMID:22053195

  13. PC viruses: How do they do that

    SciTech Connect

    Pichnarczyk, K.

    1992-07-01

    The topic of PC Viruses has been an issue for a number of years now. They've been reported in every major newspaper, tabloids, television and radio. People from all fields get viruses: government, private sector businesses, home computers, schools, computer software suppliers. A definition is proposed to introduce the virus phenomenon. Virus authors come from a variety of communities. Motives and ideologies of authors are discussed, and examples of viruses are offered. Also mentioned is the growing number of viruses developed, isolated, and never distributed to the public at large, but kept within the antivirus research community. Virus examples are offered as well. Viruses are distributed not only through bulletin boards and shareware, but also from areas previously assumed to be safe, including the threat of receiving a virus through a standard in-house function, such as an in-house hardware maintenance shop. Three categories of viruses are presented: File Infecter viruses, Boot Sector Infecters, and the new category of Directory Entry Infecter virus. Also discussed are crossover viruses, that is, viruses which utilize a variety of techniques to ensure survival. An explanation of what is occurring within every stage of various viruses is given. Replication strategies common to all three types is noted, mainly the two different replication strategies of memory resident infecters and active selection infecters. A detailed definition, description and application of a stealth virus is presented. Detection strategies are discussed as each topic in this section is completed; a high level schemata of the operation of various virus detection programs ispresented. Since most eradication today is done using virus detection/eradication software, this paper attempts to reveal the techniques used by these packages.Included in the paper is the topic of manual eradication.

  14. PC viruses: How do they do that?

    SciTech Connect

    Pichnarczyk, K.

    1992-07-01

    The topic of PC Viruses has been an issue for a number of years now. They`ve been reported in every major newspaper, tabloids, television and radio. People from all fields get viruses: government, private sector businesses, home computers, schools, computer software suppliers. A definition is proposed to introduce the virus phenomenon. Virus authors come from a variety of communities. Motives and ideologies of authors are discussed, and examples of viruses are offered. Also mentioned is the growing number of viruses developed, isolated, and never distributed to the public at large, but kept within the antivirus research community. Virus examples are offered as well. Viruses are distributed not only through bulletin boards and shareware, but also from areas previously assumed to be safe, including the threat of receiving a virus through a standard in-house function, such as an in-house hardware maintenance shop. Three categories of viruses are presented: File Infecter viruses, Boot Sector Infecters, and the new category of Directory Entry Infecter virus. Also discussed are crossover viruses, that is, viruses which utilize a variety of techniques to ensure survival. An explanation of what is occurring within every stage of various viruses is given. Replication strategies common to all three types is noted, mainly the two different replication strategies of memory resident infecters and active selection infecters. A detailed definition, description and application of a stealth virus is presented. Detection strategies are discussed as each topic in this section is completed; a high level schemata of the operation of various virus detection programs ispresented. Since most eradication today is done using virus detection/eradication software, this paper attempts to reveal the techniques used by these packages.Included in the paper is the topic of manual eradication.

  15. Zika Virus Infection and Zika Fever: Frequently Asked Questions

    MedlinePlus

    ... Updated: 25 March 2016 ABOUT ZIKA What is Zika virus infection? Zika virus infection is caused by the ... possible to characterize the disease better. How is Zika virus transmitted? Zika virus is transmitted to people through ...

  16. Quantitative nanoscale electrostatics of viruses

    NASA Astrophysics Data System (ADS)

    Hernando-Pérez, M.; Cartagena-Rivera, A. X.; Lošdorfer Božič, A.; Carrillo, P. J. P.; San Martín, C.; Mateu, M. G.; Raman, A.; Podgornik, R.; de Pablo, P. J.

    2015-10-01

    Electrostatics is one of the fundamental driving forces of the interaction between biomolecules in solution. In particular, the recognition events between viruses and host cells are dominated by both specific and non-specific interactions and the electric charge of viral particles determines the electrostatic force component of the latter. Here we probe the charge of individual viruses in liquid milieu by measuring the electrostatic force between a viral particle and the Atomic Force Microscope tip. The force spectroscopy data of co-adsorbed φ29 bacteriophage proheads and mature virions, adenovirus and minute virus of mice capsids is utilized for obtaining the corresponding density of charge for each virus. The systematic differences of the density of charge between the viral particles are consistent with the theoretical predictions obtained from X-ray structural data. Our results show that the density of charge is a distinguishing characteristic of each virus, depending crucially on the nature of the viral capsid and the presence/absence of the genetic material.Electrostatics is one of the fundamental driving forces of the interaction between biomolecules in solution. In particular, the recognition events between viruses and host cells are dominated by both specific and non-specific interactions and the electric charge of viral particles determines the electrostatic force component of the latter. Here we probe the charge of individual viruses in liquid milieu by measuring the electrostatic force between a viral particle and the Atomic Force Microscope tip. The force spectroscopy data of co-adsorbed φ29 bacteriophage proheads and mature virions, adenovirus and minute virus of mice capsids is utilized for obtaining the corresponding density of charge for each virus. The systematic differences of the density of charge between the viral particles are consistent with the theoretical predictions obtained from X-ray structural data. Our results show that the density of

  17. Structure of viruses: a short history.

    PubMed

    Rossmann, Michael G

    2013-05-01

    This review is a partially personal account of the discovery of virus structure and its implication for virus function. Although I have endeavored to cover all aspects of structural virology and to acknowledge relevant individuals, I know that I have favored taking examples from my own experience in telling this story. I am anxious to apologize to all those who I might have unintentionally offended by omitting their work. The first knowledge of virus structure was a result of Stanley's studies of tobacco mosaic virus (TMV) and the subsequent X-ray fiber diffraction analysis by Bernal and Fankuchen in the 1930s. At about the same time it became apparent that crystals of small RNA plant and animal viruses could diffract X-rays, demonstrating that viruses must have distinct and unique structures. More advances were made in the 1950s with the realization by Watson and Crick that viruses might have icosahedral symmetry. With the improvement of experimental and computational techniques in the 1970s, it became possible to determine the three-dimensional, near-atomic resolution structures of some small icosahedral plant and animal RNA viruses. It was a great surprise that the protecting capsids of the first virus structures to be determined had the same architecture. The capsid proteins of these viruses all had a 'jelly-roll' fold and, furthermore, the organization of the capsid protein in the virus were similar, suggesting a common ancestral virus from which many of today's viruses have evolved. By this time a more detailed structure of TMV had also been established, but both the architecture and capsid protein fold were quite different to that of the icosahedral viruses. The small icosahedral RNA virus structures were also informative of how and where cellular receptors, anti-viral compounds, and neutralizing antibodies bound to these viruses. However, larger lipid membrane enveloped viruses did not form sufficiently ordered crystals to obtain good X-ray diffraction

  18. Recombinant infectious bursal disease virus carrying hepatitis C virus epitopes.

    PubMed

    Upadhyay, Chitra; Ammayappan, Arun; Patel, Deendayal; Kovesdi, Imre; Vakharia, Vikram N

    2011-02-01

    The delivery of foreign epitopes by a replicating nonpathogenic avian infectious bursal disease virus (IBDV) was explored. The aim of the study was to identify regions in the IBDV genome that are amenable to the introduction of a sequence encoding a foreign peptide. By using a cDNA-based reverse genetics system, insertions or substitutions of sequences encoding epitope tags (FLAG, c-Myc, or hepatitis C virus epitopes) were engineered in the open reading frames of a nonstructural protein (VP5) and the capsid protein (VP2). Attempts were also made to generate recombinant IBDV that displayed foreign epitopes in the exposed loops (P(BC) and P(HI)) of the VP2 trimer. We successfully recovered recombinant IBDVs expressing c-Myc and two different virus-neutralizing epitopes of human hepatitis C virus (HCV) envelope glycoprotein E in the VP5 region. Western blot analyses with anti-c-Myc and anti-HCV antibodies provided positive identification of both the c-Myc and HCV epitopes that were fused to the N terminus of VP5. Genetic analysis showed that the recombinants carrying the c-Myc/HCV epitopes maintained the foreign gene sequences and were stable after several passages in Vero and 293T cells. This is the first report describing efficient expression of foreign peptides from a replication-competent IBDV and demonstrates the potential of this virus as a vector. PMID:21106739

  19. Marek's disease virus latency.

    PubMed

    Morgan, R W; Xie, Q; Cantello, J L; Miles, A M; Bernberg, E L; Kent, J; Anderson, A

    2001-01-01

    MDV latency is defined as the persistence of the viral genome in the absence of production of infectious virus except during reactivation. A number of systems for studying MDV latency exist, and most involve the use of lymphoblastoid cells or tumors. It has been difficult to divorce latency and transformation. Understanding the relationship between these two states remains a major challenge for the MDV system. Based on their patterns of expression, the MDV LATs are apt to be important in the balance between latent and lytic infections. The LATs are a complex group of transcripts. The profile of gene expression that characterizes latency differs among all herpesviruses, and MDV is no exception. MDV LATs bear little resemblance to LATs of other alphaherpesviruses or to the LATs of other lymphotropic herpesviruses. LAT splicing patterns are complex and the relationships among various spliced species or between these species and the large 10-kb transcript are unknown. In addition, the existence of any protein gene products of significance is unknown at this time. More work is needed to further investigate the significance and function of these RNAs. Better technology to construct mutants in the MDV system is badly needed, since the analysis of mutants in the chicken is a powerful and unique advantage of the MDV system. PMID:11217424

  20. Usutu virus in Africa.

    PubMed

    Nikolay, Birgit; Diallo, Mawlouth; Boye, Cheikh Saad Bouh; Sall, Amadou Alpha

    2011-11-01

    Usutu virus (USUV) was discovered in South Africa in 1959. Since then, it has been reported in several African countries including Senegal, Central African Republic, Nigeria, Uganda, Burkina Faso, Cote d'Ivoire, and Morocco. In 2001, USUV has been identified for the first time outside of Africa, namely in Europe, where it caused a significant mortality among blackbirds in Vienna, Austria. In 2009, the first two human cases of USUV infection in Europe have been reported in Italy, causing encephalitis in immunocompromised patients. The host range in Africa includes mainly Culex mosquitoes, birds, and also humans with one benign and one severe case. Given its role as a potential human pathogen and the similar appearance compared with other emerging arboviruses, it is essential to investigate the natural history and ecology of USUV in Africa. In this regard, we review the emergence of USUV in Africa, summarizing data about isolations, host range, and potential vectors, which should help to improve our understanding of the factors underlying the circulation of USUV in Europe and Africa. PMID:21767160

  1. West Nile Virus Infection.

    PubMed

    Sejvar, James J

    2016-06-01

    Although long recognized as a human pathogen, West Nile virus (WNV) emerged as a significant public health problem following its introduction and spread across North America. Subsequent years have seen a greater understanding of all aspects of this viral infection. The North American epidemic resulted in a further understanding of the virology, pathogenesis, clinical features, and epidemiology of WNV infection. Approximately 80% of human WNV infections are asymptomatic. Most symptomatic people experience an acute systemic febrile illness; less than 1% of infected people develop neuroinvasive disease, which typically manifests as meningitis, encephalitis, or anterior myelitis resulting in acute flaccid paralysis. Older age is associated with more severe illness and higher mortality; other risk factors for poor outcome have been challenging to identify. In addition to natural infection through mosquito bites, transfusion- and organ transplant-associated infections have occurred. Since there is no definitive treatment for WNV infection, protection from mosquito bites and other preventative measures are critical. WNV has reached an endemic pattern in North America, but the future epidemiologic pattern is uncertain. PMID:27337465

  2. Ebola, the killer virus.

    PubMed

    Ghazanfar, Haider; Orooj, Fizza; Abdullah, Muhammad Ahmed; Ghazanfar, Ali

    2015-01-01

    Ebola virus disease (EVD) has mostly affected economically deprived countries as limited resources adversely affect a country's infrastructure and administration. Probing into the factors that led to the widespread outbreak, setting forth plans to counter EVD cases in developing countries, and devising definitive measures to limit the spread of the disease are essential steps that must be immediately taken. In this review we summarize the pathogenesis of EVD and the factors that led to its spread. We also highlight interventions employed by certain countries that have successfully limited the epidemic, and add a few preventive measures after studying the current data. According to the available data, barriers to prevent and control the disease in affected countries include irresolute and disorganized health systems, substandard sanitary conditions, poor personal hygiene practices, and false beliefs and stigma related to EVD. The public health sector along with the respective chief authorities in developing countries must devise strategies, keeping the available resources in mind, to deal with the outbreak before it occurs. As a first step, communities should be educated on EVD's symptoms, history, mode of transmission, and methods of protection, including the importance of personal hygiene practices, via seminars, newspapers, and other social media. A popular opinion leader (POL) giving this information would further help to remove the misconception about the nature of the disease and indirectly improve the quality of life of affected patients and their families. PMID:25866626

  3. Oncolytic virus therapies.

    PubMed

    Buonaguro, Franco Maria; Tornesello, Maria Lina; Izzo, Francesco; Buonaguro, Luigi

    2012-11-01

    Oncolytic virus (OV) therapy currently represents one of the most promising approaches to cancer treatment for their dual anticancer mechanisms: direct lysis of cancer cells (oncolytic feature) and activation of the immunosystem (cancer vaccine aspect). The latter demonstrates the advantage of a multi-target approach against multiple tumor-associated antigens. Since the 2005 SFDA (the Chinese FDA) approval for the clinical use of Oncorine™, the first human OV-based cancer treatment, more than 200 patents have been filed worldwide and several Phase I/II studies have been conducted. This patent review analyzes patents and clinical studies of the most promising OV products to highlight the pros and cons of this innovative anticancer approach, which is currently being tested in several cancers (i.e., hepatocellular carcinoma, melanoma and glioblastoma) by systemic as well as intratumoral injection. Clinical results, although effective only for a limited period of time, are encouraging. Combined treatments with radio or chemotherapeutic protocols are also in progress. PMID:24236929

  4. Hepatitis B virus morphogenesis

    PubMed Central

    Bruss, Volker

    2007-01-01

    The hepatitis B virus (HBV) particle consists of an envelope containing three related surface proteins and probably lipid and an icosahedral nucleocapsid of approximately 30 nm diameter enclosing the viral DNA genome and DNA polymerase. The capsid is formed in the cytosol of the infected cell during packaging of an RNA pregenome replication complex by multiple copies of a 21-kDa C protein. The capsid gains the ability to bud during synthesis of the viral DNA genome by reverse transcription of the pregenome in the lumen of the particle. The three envelope proteins S, M, and L shape a complex transmembrane fold at the endoplasmic reticulum, and form disulfide-linked homo- and heterodimers. The transmembrane topology of a fraction of the large envelope protein L changes post-translationally, therefore, the N terminal domain of L (preS) finally appears on both sides of the membrane. During budding at an intracellular membrane, a short linear domain in the cytosolic preS region interacts with binding sites on the capsid surface. The virions are subsequently secreted into the blood. In addition, the surface proteins can bud in the absence of capsids and form subviral lipoprotein particles of 20 nm diameter which are also secreted. PMID:17206755

  5. Stochastic analysis of virus transport in aquifers

    USGS Publications Warehouse

    Campbell, Rehmann L.L.; Welty, C.; Harvey, R.W.

    1999-01-01

    A large-scale model of virus transport in aquifers is derived using spectral perturbation analysis. The effects of spatial variability in aquifer hydraulic conductivity and virus transport (attachment, detachment, and inactivation) parameters on large-scale virus transport are evaluated. A stochastic mean model of virus transport is developed by linking a simple system of local-scale free-virus transport and attached-virus conservation equations from the current literature with a random-field representation of aquifer and virus transport properties. The resultant mean equations for free and attached viruses are found to differ considerably from the local-scale equations on which they are based and include effects such as a free-virus effective velocity that is a function of aquifer heterogeneity as well as virus transport parameters. Stochastic mean free-virus breakthrough curves are compared with local model output in order to observe the effects of spatial variability on mean one-dimensional virus transport in three-dimensionally heterogeneous porous media. Significant findings from this theoretical analysis include the following: (1) Stochastic model breakthrough occurs earlier than local model breakthrough, and this effect is most pronounced for the least conductive aquifers studied. (2) A high degree of aquifer heterogeneity can lead to virus breakthrough actually preceding that of a conservative tracer. (3) As the mean hydraulic conductivity is increased, the mean model shows less sensitivity to the variance of the natural-logarithm hydraulic conductivity and mean virus diameter. (4) Incorporation of a heterogeneous colloid filtration term results in higher predicted concentrations than a simple first-order adsorption term for a given mean attachment rate. (5) Incorporation of aquifer heterogeneity leads to a greater range of virus diameters for which significant breakthrough occurs. (6) The mean model is more sensitive to the inactivation rate of viruses

  6. Viruses and viruslike particles of eukaryotic algae.

    PubMed Central

    Van Etten, J L; Lane, L C; Meints, R H

    1991-01-01

    Until recently there was little interest or information on viruses and viruslike particles of eukaryotic algae. However, this situation is changing. In the past decade many large double-stranded DNA-containing viruses that infect two culturable, unicellular, eukaryotic green algae have been discovered. These viruses can be produced in large quantities, assayed by plaque formation, and analyzed by standard bacteriophage techniques. The viruses are structurally similar to animal iridoviruses, their genomes are similar to but larger (greater than 300 kbp) than that of poxviruses, and their infection process resembles that of bacteriophages. Some of the viruses have DNAs with low levels of methylated bases, whereas others have DNAs with high concentrations of 5-methylcytosine and N6-methyladenine. Virus-encoded DNA methyltransferases are associated with the methylation and are accompanied by virus-encoded DNA site-specific (restriction) endonucleases. Some of these enzymes have sequence specificities identical to those of known bacterial enzymes, and others have previously unrecognized specificities. A separate rod-shaped RNA-containing algal virus has structural and nucleotide sequence affinities to higher plant viruses. Quite recently, viruses have been associated with rapid changes in marine algal populations. In the next decade we envision the discovery of new algal viruses, clarification of their role in various ecosystems, discovery of commercially useful genes in these viruses, and exploitation of algal virus genetic elements in plant and algal biotechnology. Images PMID:1779928

  7. Autophagic machinery activated by dengue virus enhances virus replication

    SciTech Connect

    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.

    2008-05-10

    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.

  8. [Bats and Viruses: complex relationships].

    PubMed

    Rodhain, E

    2015-10-01

    With more than 1 200 species, bats and flying foxes (Order Chiroptera) constitute the most important and diverse order of Mammals after Rodents. Many species of bats are insectivorous while others are frugivorous and few of them are hematophagous. Some of these animals fly during the night, others are crepuscular or diurnal. Some fly long distances during seasonal migrations. Many species are colonial cave-dwelling, living in a rather small home range while others are relatively solitary. However, in spite of the importance of bats for terrestrial biotic communities and ecosystem ecology, the diversity in their biology and lifestyles remain poorly known and underappreciated. More than sixty viruses have been detected or isolated in bats; these animals are therefore involved in the natural cycles of many of them. This is the case, for instance, of rabies virus and other Lyssavirus (Family Rhabdoviridae), Nipah and Hendra viruses (Paramyxoviridae), Ebola and Marburg viruses (Filoviridae), SARS-CoV and MERS-CoV (Coronaviridae). For these zoonotic viruses, a number of bat species are considered as important reservoir hosts, efficient disseminators or even directly responsible of the transmission. Some of these bat-borne viruses cause highly pathogenic diseases while others are of potential significance for humans and domestic or wild animals; so, bats are an important risk in human and animal public health. Moreover, some groups of viruses developed through different phylogenetic mechanisms of coevolution between viruses and bats. The fact that most of these viral infections are asymptomatic in bats has been observed since a long time but the mechanisms of the viral persistence are not clearly understood. The various bioecology of the different bat populations allows exchange of virus between migrating and non-migrating conspecific species. For a better understanding of the role of bats in the circulation of these viral zoonoses, epidemiologists must pay attention to

  9. Circulative, “Nonpropagative” Virus Transmission: An orchestra of virus, insect and plant derived instruments

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The many species of plant viruses within the Luteoviridae, Geminiviridae and Nanoviridae are all transmitted by phloem feeding insects in a circulative, nonpropagative manner. The precise route of virus movement through the vector can differ across and within virus families, but these viruses all sh...

  10. Coping with Computer Viruses: General Discussion and Review of Symantec Anti-Virus for the Macintosh.

    ERIC Educational Resources Information Center

    Primich, Tracy

    1992-01-01

    Discusses computer viruses that attack the Macintosh and describes Symantec AntiVirus for Macintosh (SAM), a commercial program designed to detect and eliminate viruses; sample screen displays are included. SAM is recommended for use in library settings as well as two public domain virus protection programs. (four references) (MES)

  11. Strains of Citrus tristeza virus do not exclude superinfection by other strains of the virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Superinfection exclusion or homologous interference, a phenomenon in which a primary viral infection prevents a secondary infection with the same or closely-related virus, has been observed commonly for viruses in various systems, including viruses of bacteria, plants, and animals. With plant viruse...

  12. Generation of virus like particles for epizootic hemorrhagic disease virus.

    PubMed

    Forzan, Mario; Maan, Sushila; Mazzei, Maurizio; Belaganahalli, Manjunatha N; Bonuccelli, Lucia; Calamari, Monica; Carrozza, Maria Luisa; Cappello, Valentina; Di Luca, Mariagrazia; Bandecchi, Patrizia; Mertens, Peter P C; Tolari, Francesco

    2016-08-01

    Epizootic hemorrhagic disease virus (EHDV) is a distinct species within the genus Orbivirus, within the family Reoviridae. The epizootic hemorrhagic disease virus genome comprises ten segments of linear, double stranded (ds) RNA, which are packaged within each virus particle. The EHDV virion has a three layered capsid-structure, generated by four major viral proteins: VP2 and VP5 (outer capsid layer); VP7 (intermediate, core-surface layer) and VP3 (innermost, sub-core layer). Although EHDV infects cattle sporadically, several outbreaks have recently occurred in this species in five Mediterranean countries, indicating a potential threat to the European cattle industry. EHDV is transmitted by biting midges of the genus Culicoides, which can travel long distances through wind-born movements (particularly over water), increasing the potential for viral spread in new areas/countries. Expression systems to generate self-assembled virus like particles (VLPs) by simultaneous expression of the major capsid-proteins, have been established for several viruses (including bluetongue virus). This study has developed expression systems for production of EHDV VLPs, for use as non-infectious antigens in both vaccinology and serology studies, avoiding the risk of genetic reassortment between vaccine and field strains and facilitating large scale antigen production. Genes encoding the four major-capsid proteins of a field strain of EHDV-6, were isolated and cloned into transfer vectors, to generate two recombinant baculoviruses. The expression of these viral genes was assessed in insect cells by monitoring the presence of specific viral mRNAs and by western blotting. Electron microscopy studies confirmed the formation and purification of assembled VLPs. PMID:27473984

  13. Quantitative nanoscale electrostatics of viruses.

    PubMed

    Hernando-Pérez, M; Cartagena-Rivera, A X; Lošdorfer Božič, A; Carrillo, P J P; San Martín, C; Mateu, M G; Raman, A; Podgornik, R; de Pablo, P J

    2015-11-01

    Electrostatics is one of the fundamental driving forces of the interaction between biomolecules in solution. In particular, the recognition events between viruses and host cells are dominated by both specific and non-specific interactions and the electric charge of viral particles determines the electrostatic force component of the latter. Here we probe the charge of individual viruses in liquid milieu by measuring the electrostatic force between a viral particle and the Atomic Force Microscope tip. The force spectroscopy data of co-adsorbed ϕ29 bacteriophage proheads and mature virions, adenovirus and minute virus of mice capsids is utilized for obtaining the corresponding density of charge for each virus. The systematic differences of the density of charge between the viral particles are consistent with the theoretical predictions obtained from X-ray structural data. Our results show that the density of charge is a distinguishing characteristic of each virus, depending crucially on the nature of the viral capsid and the presence/absence of the genetic material. PMID:26228582

  14. Designing herpes viruses as oncolytics

    PubMed Central

    Peters, Cole; Rabkin, Samuel D

    2015-01-01

    Oncolytic herpes simplex virus (oHSV) was one of the first genetically-engineered oncolytic viruses. Because HSV is a natural human pathogen that can cause serious disease, it is incumbent that it can be genetically-engineered or significantly attenuated for safety. Here, we present a detailed explanation of the functions of HSV-1 genes frequently mutated to endow oncolytic activity. These genes are nonessential for growth in tissue culture cells but are important for growth in postmitotic cells, interfering with intrinsic antiviral and innate immune responses or causing pathology, functions dispensable for replication in cancer cells. Understanding the function of these genes leads to informed creation of new oHSVs with better therapeutic efficacy. Virus infection and replication can also be directed to cancer cells through tumor-selective receptor binding and transcriptional- or post-transcriptional miRNA-targeting, respectively. In addition to the direct effects of oHSV on infected cancer cells and tumors, oHSV can be “armed” with transgenes that are: reporters, to track virus replication and spread; cytotoxic, to kill uninfected tumor cells; immune modulatory, to stimulate antitumor immunity; or tumor microenvironment altering, to enhance virus spread or to inhibit tumor growth. In addition to HSV-1, other alphaherpesviruses are also discussed for their oncolytic activity. PMID:26462293

  15. Optical tweezers to study viruses.

    PubMed

    Arias-Gonzalez, J Ricardo

    2013-01-01

    A virus is a complex molecular machine that propagates by channeling its genetic information from cell to cell. Unlike macroscopic engines, it operates in a nanoscopic world under continuous thermal agitation. Viruses have developed efficient passive and active strategies to pack and release nucleic acids. Some aspects of the dynamic behavior of viruses and their substrates can be studied using structural and biochemical techniques. Recently, physical techniques have been applied to dynamic studies of viruses in which their intrinsic mechanical activity can be measured directly. Optical tweezers are a technology that can be used to measure the force, torque and strain produced by molecular motors, as a function of time and at the single-molecule level. Thanks to this technique, some bacteriophages are now known to be powerful nanomachines; they exert force in the piconewton range and their motors work in a highly coordinated fashion for packaging the viral nucleic acid genome. Nucleic acids, whose elasticity and condensation behavior are inherently coupled to the viral packaging mechanisms, are also amenable to examination with optical tweezers. In this chapter, we provide a comprehensive analysis of this laser-based tool, its combination with imaging methods and its application to the study of viruses and viral molecules. PMID:23737055

  16. Droplet Microfluidics for Virus Discovery

    NASA Astrophysics Data System (ADS)

    Rotem, Assaf; Cockrell, Shelley; Guo, Mira; Pipas, James; Weitz, David

    2012-02-01

    The ability to detect, isolate, and characterize an infectious agent is important for diagnosing and curing infectious diseases. Detecting new viral diseases is a challenge because the number of virus particles is often low and/or localized to a small subset of cells. Even if a new virus is detected, it is difficult to isolate it from clinical or environmental samples where multiple viruses are present each with very different properties. Isolation is crucial for whole genome sequencing because reconstructing a genome from fragments of many different genomes is practically impossible. We present a Droplet Microfluidics platform that can detect, isolate and sequence single viral genomes from complex samples containing mixtures of many viruses. We use metagenomic information about the sample of mixed viruses to select a short genomic sequence whose genome we are interested in characterizing. We then encapsulate single virions from the same sample in picoliter volume droplets and screen for successful PCR amplification of the sequence of interest. The selected drops are pooled and their contents sequenced to reconstruct the genome of interest. This method provides a general tool for detecting, isolating and sequencing genetic elements in clinical and environmental samples.

  17. Control of viruses infecting grapevine.

    PubMed

    Maliogka, Varvara I; Martelli, Giovanni P; Fuchs, Marc; Katis, Nikolaos I

    2015-01-01

    Grapevine is a high value vegetatively propagated fruit crop that suffers from numerous viruses, including some that seriously affect the profitability of vineyards. Nowadays, 64 viruses belonging to different genera and families have been reported in grapevines and new virus species will likely be described in the future. Three viral diseases namely leafroll, rugose wood, and infectious degeneration are of major economic importance worldwide. The viruses associated with these diseases are transmitted by mealybugs, scale and soft scale insects, or dagger nematodes. Here, we review control measures of the major grapevine viral diseases. More specifically, emphasis is laid on (i) approaches for the production of clean stocks and propagative material through effective sanitation, robust diagnosis, as well as local and regional certification efforts, (ii) the management of vectors of viruses using cultural, biological, and chemical methods, and (iii) the production of resistant grapevines mainly through the application of genetic engineering. The benefits and limitations of the different control measures are discussed with regard to accomplishments and future research directions. PMID:25591880

  18. Viruses and thyroiditis: an update

    PubMed Central

    Desailloud, Rachel; Hober, Didier

    2009-01-01

    Viral infections are frequently cited as a major environmental factor involved in subacute thyroiditis and autoimmune thyroid diseases This review examines the data related to the role of viruses in the development of thyroiditis. Our research has been focused on human data. We have reviewed virological data for each type of thyroiditis at different levels of evidence; epidemiological data, serological data or research on circulating viruses, direct evidence of thyroid tissue infection. Interpretation of epidemiological and serological data must be cautious as they don't prove that this pathogen is responsible for the disease. However, direct evidence of the presence of viruses or their components in the organ are available for retroviruses (HFV) and mumps in subacute thyroiditis, for retroviruses (HTLV-1, HFV, HIV and SV40) in Graves's disease and for HTLV-1, enterovirus, rubella, mumps virus, HSV, EBV and parvovirus in Hashimoto's thyroiditis. However, it remains to determine whether they are responsible for thyroid diseases or whether they are just innocent bystanders. Further studies are needed to clarify the relationship between viruses and thyroid diseases, in order to develop new strategies for prevention and/or treatment. PMID:19138419

  19. Role of Lipids in Virus Replication

    PubMed Central

    Lorizate, Maier; Kräusslich, Hans-Georg

    2011-01-01

    Viruses intricately interact with and modulate cellular membranes at several stages of their replication, but much less is known about the role of viral lipids compared to proteins and nucleic acids. All animal viruses have to cross membranes for cell entry and exit, which occurs by membrane fusion (in enveloped viruses), by transient local disruption of membrane integrity, or by cell lysis. Furthermore, many viruses interact with cellular membrane compartments during their replication and often induce cytoplasmic membrane structures, in which genome replication and assembly occurs. Recent studies revealed details of membrane interaction, membrane bending, fission, and fusion for a number of viruses and unraveled the lipid composition of raft-dependent and -independent viruses. Alterations of membrane lipid composition can block viral release and entry, and certain lipids act as fusion inhibitors, suggesting a potential as antiviral drugs. Here, we review viral interactions with cellular membranes important for virus entry, cytoplasmic genome replication, and virus egress. PMID:21628428

  20. Many Americans Misinformed about Zika Virus

    MedlinePlus

    ... news/fullstory_158016.html Many Americans Misinformed About Zika Virus Harvard poll shows they don't know how ... when it comes to understanding the risks of Zika virus, a new Harvard poll has found. The mosquito- ...

  1. FAQ: West Nile Virus and Dead Birds

    MedlinePlus

    ... Education Public Service Videos West Nile Virus & Dead Birds Recommend on Facebook Tweet Share Compartir On this ... dead bird sightings to local authorities. How do birds get infected with West Nile virus? West Nile ...

  2. A "virus" disease of chinook salmon

    USGS Publications Warehouse

    Ross, A.J.; Rucker, R.R.

    1960-01-01

    Epizootics among chinook salmon fingerlings at the Coleman National Fish Hatchery have occurred periodically since 1941. A virus or virus-like filterable agent has been demonstrated to be the causative agent of this disease.

  3. Influenza Virus Infection of Marine Mammals.

    PubMed

    Fereidouni, Sasan; Munoz, Olga; Von Dobschuetz, Sophie; De Nardi, Marco

    2016-03-01

    Interspecies transmission may play a key role in the evolution and ecology of influenza A viruses. The importance of marine mammals as hosts or carriers of potential zoonotic pathogens such as highly pathogenic H5 and H7 influenza viruses is not well understood. The fact that influenza viruses are some of the few zoonotic pathogens known to have caused infection in marine mammals, evidence for direct transmission of influenza A virus H7N7 subtype from seals to man, transmission of pandemic H1N1 influenza viruses to seals and also limited evidence for long-term persistence of influenza B viruses in seal populations without significant genetic change, makes monitoring of influenza viruses in marine mammal populations worth being performed. In addition, such monitoring studies could be a great tool to better understand the ecology of influenza viruses in nature. PMID:25231137

  4. Swine Influenza/Variant Influenza Viruses

    MedlinePlus

    ... Humans Key Facts about Human Infections with Variant Viruses Interim Guidance for Clinicians on Human Infections Background, Risk Assessment & Reporting Reported Infections with Variant Influenza Viruses in the United States since 2005 Prevention Treatment ...

  5. Control of virus diseases of berry crops.

    PubMed

    Martin, Robert R; Tzanetakis, Ioannis E

    2015-01-01

    Virus control in berry crops starts with the development of plants free of targeted pathogens, usually viruses, viroids, phytoplasmas, and systemic bacteria, through a combination of testing and therapy. These then become the top-tier plants in certification programs and are the source from which all certified plants are produced, usually after multiple cycles of propagation. In certification schemes, efforts are made to produce plants free of the targeted pathogens to provide plants of high health status to berry growers. This is achieved using a systems approach to manage virus vectors. Once planted in fruit production fields, virus control shifts to disease control where efforts are focused on controlling viruses or virus complexes that result in disease. In fruiting fields, infection with a virus that does not cause disease is of little concern to growers. Virus control is based on the use of resistance and tolerance, vector management, and isolation. PMID:25591882

  6. Avian Influenza A Virus Infections in Humans

    MedlinePlus

    ... Research Making a Candidate Vaccine Virus Related Links Influenza Types Seasonal Avian Swine Variant Pandemic Other Get ... Submit What's this? Submit Button Past Newsletters Avian Influenza A Virus Infections in Humans Language: English Españ ...

  7. About Epstein-Barr Virus (EBV)

    MedlinePlus

    ... Providers Laboratory Testing References & Resources About Epstein-Barr Virus (EBV) Recommend on Facebook Tweet Share Compartir On ... Page Symptoms Transmission Diagnosis Prevention & Treatment Epstein-Barr virus (EBV), also known as human herpesvirus 4, is ...

  8. A Literature Review of Zika Virus.

    PubMed

    Plourde, Anna R; Bloch, Evan M

    2016-07-01

    Zika virus is a mosquitoborne flavivirus that is the focus of an ongoing pandemic and public health emergency. Previously limited to sporadic cases in Africa and Asia, the emergence of Zika virus in Brazil in 2015 heralded rapid spread throughout the Americas. Although most Zika virus infections are characterized by subclinical or mild influenza-like illness, severe manifestations have been described, including Guillain-Barre syndrome in adults and microcephaly in babies born to infected mothers. Neither an effective treatment nor a vaccine is available for Zika virus; therefore, the public health response primarily focuses on preventing infection, particularly in pregnant women. Despite growing knowledge about this virus, questions remain regarding the virus's vectors and reservoirs, pathogenesis, genetic diversity, and potential synergistic effects of co-infection with other circulating viruses. These questions highlight the need for research to optimize surveillance, patient management, and public health intervention in the current Zika virus epidemic. PMID:27070380

  9. Uveitis Associated with Zika Virus Infection.

    PubMed

    Furtado, João M; Espósito, Danillo L; Klein, Taline M; Teixeira-Pinto, Tomás; da Fonseca, Benedito A

    2016-07-28

    An adult patient recovered from acute Zika virus infection, but ocular symptoms subsequently developed. Anterior uveitis was diagnosed, and Zika virus was identified in the aqueous humor. PMID:27332784

  10. Scientists Try to Stop Another Deadly Virus

    MedlinePlus

    ... Try to Stop Another Deadly Virus Junin, an Ebola-like disease in Argentina, has a death rate ... companies that developed a similar treatment against the Ebola virus during the 2014-2015 outbreak. That drug, ...

  11. Historical review: viruses, crystals and geodesic domes.

    PubMed

    Morgan, Gregory J

    2003-02-01

    In the mid 1950s, Francis Crick and James Watson attempted to explain the structure of spherical viruses. They hypothesized that spherical viruses consist of 60 identical equivalently situated subunits. Such an arrangement has icosahedral symmetry. Subsequent biophysical and electron micrographic data suggested that many viruses had >60 subunits. Drawing inspiration from architecture, Donald Caspar and Aaron Klug discovered a solution to the problem - they proposed that spherical viruses were structured like miniature geodesic domes. PMID:12575996

  12. Characteristics of Filoviridae: Marburg and Ebola Viruses

    NASA Astrophysics Data System (ADS)

    Beer, Brigitte; Kurth, Reinhard; Bukreyev, Alexander

    Filoviruses are enveloped, nonsegmented negative-stranded RNA viruses. The two species, Marburg and Ebola virus, are serologically, biochemically, and genetically distinct. Marburg virus was first isolated during an outbreak in Europe in 1967, and Ebola virus emerged in 1976 as the causative agent of two simultaneous outbreaks in southern Sudan and northern Zaire. Although the main route of infection is known to be person-to-person transmission by intimate contact, the natural reservoir for filoviruses still remains a mystery.

  13. Reverse Genetics of Respiratory Syncytial Virus.

    PubMed

    Stobart, Christopher C; Hotard, Anne L; Meng, Jia; Moore, Martin L

    2016-01-01

    Respiratory syncytial virus (RSV) is a negative-strand RNA virus that is associated with severe lower respiratory tract infections in young infants and the elderly. RSV remains a leading cause worldwide of infant mortality, and despite the high clinical and economic burden of the virus there are currently no available vaccines. Here, we describe the methods for recovery of recombinant RSV viruses using a bacterial artificial chromosome and methods related to procurement and expansion of stocks of RSV mutants. PMID:27464692

  14. [Zika virus, an emerging threat].

    PubMed

    Salinas, Sara; Foulongne, Vincent; Loustalot, Fabien; Fournier-Wirth, Chantal; Molès, Jean-Pierre; Briant, Laurence; Nagot, Nicolas; Van de Perre, Philippe; Simonin, Yannick

    2016-04-01

    Zika virus, discovered in 1947, is particularly publicized because of its involvement in a major epidemic that began in 2015 and which epicenter is located in Latin America, mainly in Brazil. In the majority of cases (70-80 %) the infection is asymptomatic, however in some patients, moderate fever, skin rash, conjunctivitis and myalgia may occur. More alarming, neurological complications are reported, in particular cases of microcephaly probably resulting from the infection of women in the first or second trimester of pregnancy. Moreover, Guillain-Barré syndromes have also been identified in patients whose infection was confirmed. The extent of the current outbreak reveals the very primitive state of knowledge about the pathophysiology of this virus. Thus, a global effort is being undertaken in order to quickly characterize the molecular interaction of the virus with human cells, but also to develop specific diagnostic assays and vaccinal approaches. PMID:27137695

  15. Hepatitis Virus Infections in Poultry.

    PubMed

    Yugo, Danielle M; Hauck, Ruediger; Shivaprasad, H L; Meng, Xiang-Jin

    2016-09-01

    Viral hepatitis in poultry is a complex disease syndrome caused by several viruses belonging to different families including avian hepatitis E virus (HEV), duck hepatitis B virus (DHBV), duck hepatitis A virus (DHAV-1, -2, -3), duck hepatitis virus Types 2 and 3, fowl adenoviruses (FAdV), and turkey hepatitis virus (THV). While these hepatitis viruses share the same target organ, the liver, they each possess unique clinical and biological features. In this article, we aim to review the common and unique features of major poultry hepatitis viruses in an effort to identify the knowledge gaps and aid the prevention and control of poultry viral hepatitis. Avian HEV is an Orthohepevirus B in the family Hepeviridae that naturally infects chickens and consists of three distinct genotypes worldwide. Avian HEV is associated with hepatitis-splenomegaly syndrome or big liver and spleen disease in chickens, although the majority of the infected birds are subclinical. Avihepadnaviruses in the family of Hepadnaviridae have been isolated from ducks, snow geese, white storks, grey herons, cranes, and parrots. DHBV evolved with the host as a noncytopathic form without clinical signs and rarely progressed to chronicity. The outcome for DHBV infection varies by the host's ability to elicit an immune response and is dose and age dependent in ducks, thus mimicking the pathogenesis of human hepatitis B virus (HBV) infections and providing an excellent animal model for human HBV. DHAV is a picornavirus that causes a highly contagious virus infection in ducks with up to 100% flock mortality in ducklings under 6 wk of age, while older birds remain unaffected. The high morbidity and mortality has an economic impact on intensive duck production farming. Duck hepatitis virus Types 2 and 3 are astroviruses in the family of Astroviridae with similarity phylogenetically to turkey astroviruses, implicating the potential for cross-species infections between strains. Duck astrovirus (DAstV) causes

  16. [Capping strategies in RNA viruses].

    PubMed

    Bouvet, Mickaël; Ferron, François; Imbert, Isabelle; Gluais, Laure; Selisko, Barbara; Coutard, Bruno; Canard, Bruno; Decroly, Etienne

    2012-04-01

    Most viruses use the mRNA-cap dependent cellular translation machinery to translate their mRNAs into proteins. The addition of a cap structure at the 5' end of mRNA is therefore an essential step for the replication of many virus families. Additionally, the cap protects the viral RNA from degradation by cellular nucleases and prevents viral RNA recognition by innate immunity mechanisms. Viral RNAs acquire their cap structure either by using cellular capping enzymes, by stealing the cap of cellular mRNA in a process named "cap snatching", or using virus-encoded capping enzymes. Many viral enzymes involved in this process have recently been structurally and functionally characterized. These studies have revealed original cap synthesis mechanisms and pave the way towards the development of specific inhibitors bearing antiviral drug potential. PMID:22549871

  17. Neutralizing antibodies to different proteins of African swine fever virus inhibit both virus attachment and internalization.

    PubMed Central

    Gómez-Puertas, P; Rodríguez, F; Oviedo, J M; Ramiro-Ibáñez, F; Ruiz-Gonzalvo, F; Alonso, C; Escribano, J M

    1996-01-01

    African swine fever virus induces in convalescent pigs antibodies that neutralized the virus before and after binding to susceptible cells, inhibiting both virus attachment and internalization. A further analysis of the neutralization mechanisms mediated by the different viral proteins showed that antibodies to proteins p72 and p54 are involved in the inhibition of a first step of the replication cycle related to virus attachment, while antibodies to protein p30 are implicated in the inhibition of virus internalization. PMID:8764090

  18. Ecological dynamics of emerging bat virus spillover.

    PubMed

    Plowright, Raina K; Eby, Peggy; Hudson, Peter J; Smith, Ina L; Westcott, David; Bryden, Wayne L; Middleton, Deborah; Reid, Peter A; McFarlane, Rosemary A; Martin, Gerardo; Tabor, Gary M; Skerratt, Lee F; Anderson, Dale L; Crameri, Gary; Quammen, David; Jordan, David; Freeman, Paul; Wang, Lin-Fa; Epstein, Jonathan H; Marsh, Glenn A; Kung, Nina Y; McCallum, Hamish

    2015-01-01

    Viruses that originate in bats may be the most notorious emerging zoonoses that spill over from wildlife into domestic animals and humans. Understanding how these infections filter through ecological systems to cause disease in humans is of profound importance to public health. Transmission of viruses from bats to humans requires a hierarchy of enabling conditions that connect the distribution of reservoir hosts, viral infection within these hosts, and exposure and susceptibility of recipient hosts. For many emerging bat viruses, spillover also requires viral shedding from bats, and survival of the virus in the environment. Focusing on Hendra virus, but also addressing Nipah virus, Ebola virus, Marburg virus and coronaviruses, we delineate this cross-species spillover dynamic from the within-host processes that drive virus excretion to land-use changes that increase interaction among species. We describe how land-use changes may affect co-occurrence and contact between bats and recipient hosts. Two hypotheses may explain temporal and spatial pulses of virus shedding in bat populations: episodic shedding from persistently infected bats or transient epidemics that occur as virus is transmitted among bat populations. Management of livestock also may affect the probability of exposure and disease. Interventions to decrease the probability of virus spillover can be implemented at multiple levels from targeting the reservoir host to managing recipient host exposure and susceptibility. PMID:25392474

  19. Citrus tristeza virus-host interactions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Citrus tristeza virus (CTV) is a phloem-limited virus whose natural host range is restricted to citrus and related species. Although the virus has killed millions of trees, almost destroying whole industries, and continually limits production in many citrus growing areas, most isolates are mild or s...

  20. Detection and Diagnosis of Plant Viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Diseases caused by viruses are a constant and major problem for crop production worldwide. Human interest in plant genetic resources and globalization of human activities has inadvertently contributed to the spread of viruses throughout the world, increasing the frequency of plant virus outbreaks. C...

  1. Virus detection and quantification using electrical parameters

    PubMed Central

    Ahmad, Mahmoud Al; Mustafa, Farah; Ali, Lizna M.; Rizvi, Tahir A.

    2014-01-01

    Here we identify and quantitate two similar viruses, human and feline immunodeficiency viruses (HIV and FIV), suspended in a liquid medium without labeling, using a semiconductor technique. The virus count was estimated by calculating the impurities inside a defined volume by observing the change in electrical parameters. Empirically, the virus count was similar to the absolute value of the ratio of the change of the virus suspension dopant concentration relative to the mock dopant over the change in virus suspension Debye volume relative to mock Debye volume. The virus type was identified by constructing a concentration-mobility relationship which is unique for each kind of virus, allowing for a fast (within minutes) and label-free virus quantification and identification. For validation, the HIV and FIV virus preparations were further quantified by a biochemical technique and the results obtained by both approaches corroborated well. We further demonstrate that the electrical technique could be applied to accurately measure and characterize silica nanoparticles that resemble the virus particles in size. Based on these results, we anticipate our present approach to be a starting point towards establishing the foundation for label-free electrical-based identification and quantification of an unlimited number of viruses and other nano-sized particles. PMID:25355078

  2. The greasy response to virus infections

    PubMed Central

    Tanner, Lukas Bahati; Lee, Benhur

    2013-01-01

    Previews Virus replication requires lipid metabolism, but how lipids mediate virus infection remains obscure. In this issue, Amini-Bavil-Olyaee et al. (2013) reveal that IFITM proteins disturb cholesterol homeostasis to block virus entry. Previously in Cell, Morita and colleagues (2013) showed the antiviral potency of the lipid mediator protectin D1. PMID:23601099

  3. Computer Viruses and Safe Educational Practices.

    ERIC Educational Resources Information Center

    Azarmsa, Reza

    1991-01-01

    This discussion of computer viruses explains how these viruses may be transmitted, describes their effects on data and/or computer application programs, and identifies three groups that propagate them. Ten major viruses are listed and described, and measures to deal with them are discussed. Nineteen antiviral programs are also listed and…

  4. MODEL OF VIRUS TRANSPORT IN UNSATURATED SOIL

    EPA Science Inventory

    As a result of the recently-proposed mandatory ground-water disinfection requirements to inactivate viruses in potable water supplies, there has been increasing interest in virus fate and transport in the subsurface. everal models have been developed to predict the fate of viruse...

  5. The receptor preference of influenza viruses

    PubMed Central

    Meng, Bo; Marriott, Anthony C.; Dimmock, Nigel J.

    2010-01-01

    Please cite this paper as: Meng et al. (2010) The receptor preference of influenza viruses. Influenza and Other Respiratory Viruses 4(3), 147–153. Objectives  The cell surface receptor used by an influenza virus to infect that cell is an N‐acetyl neuraminic acid (NANA) residue terminally linked by an alpha2,3 or alpha2,6 bond to a carbohydrate moiety of a glycoprotein or glycolipid. Our aim was to determine a quick and technically simple method to determine cell receptor usage by whole influenza A virus particles. Methods  We employed surface plasmon resonance to detect the binding of viruses to fetuin, a naturally occurring glycoprotein that has both alpha2,3‐ and alpha2,6‐linked NANA, and free 3′‐sialyllactose or 6′‐sialyllactose to compete virus binding. All virus stocks were produced in embryonated chicken’s eggs. Results  The influenza viruses tested bound preferentially to NANAalpha2,3Gal or to NANAalpha2,6Gal, or showed no preference. Two PR8 viruses had different binding preferences. Binding preferences of viruses correlated well with their known biological properties. Conclusions  Our data suggest that it is not easy to predict receptor usage by influenza viruses. However, direct experimental determination as described here can inform experiments concerned with viral pathogenesis, biology and structure. In principle, the methodology can be used for any virus that binds to a terminal NANA residue. PMID:20409211

  6. CLASSIFICATION AND NOMENCLATURE OF VIRUSES OF CYANOBACTERIA

    EPA Science Inventory

    The Study Group finds it appropriate that viruses which have as their host cyanobacteria (blue-green algae) should be grouped within the well-categorized families of the bacterial viruses. Thus, the term cyanophage is adopted as a synonym for the vernacular name BGA virus (BGAV) ...

  7. Focus on: Hendra virus in Australia.

    PubMed

    Hughes, Kristopher

    2014-11-29

    Cases of Hendra virus infection in horses in Australia have been seen regularly since the virus was first isolated in 1994. Kristopher Hughes, associate professor of equine medicine at Charles Sturt University in Australia, gives an overview of how knowledge of the virus has developed in the past 20 years. PMID:25431383

  8. Blackberry (Rubus spp.)-Virus Diseases

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many viruses have been found in blackberries in the Pacific Northwest. Blackberry calico virus (a carlavirus) is universally present in older commercial 'Thornless Loganberry' fields. Similar calico diseases occur in field-run 'Marion', 'Chehalem', 'Olallie', and 'Waldo' blackberries. Other virus di...

  9. Ebola Virus Persistence in Semen Ex Vivo

    PubMed Central

    Fischer, Robert J.; Judson, Seth; Miazgowicz, Kerri; Bushmaker, Trent

    2016-01-01

    On March 20, 2015, a case of Ebola virus disease was identified in Liberia that most likely was transmitted through sexual contact. We assessed the efficiency of detecting Ebola virus in semen samples by molecular diagnostics and the stability of Ebola virus in ex vivo semen under simulated tropical conditions. PMID:26811984

  10. Emerging foodborne and agriculture-related viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Viruses rapidly evolve and can emerge in unpredictable ways. Mechanisms by which food-borne viruses may enter human populations and become pathogens is discussed. It is known the majority of viruses emerge from zoonotic animal reservoirs, often by adapting and infecting intermediate hosts, such as ...

  11. Viruses take center stage in cellular evolution

    PubMed Central

    Claverie, Jean-Michel

    2006-01-01

    The origins of viruses are shrouded in mystery, but advances in genomics and the discovery of highly complex giant DNA viruses have stimulated new hypotheses that DNA viruses were involved in the emergence of the eukaryotic cell nucleus, and that they are worthy of being considered as living organisms. PMID:16787527

  12. Lagos bat virus in Kenya.

    PubMed

    Kuzmin, Ivan V; Niezgoda, Michael; Franka, Richard; Agwanda, Bernard; Markotter, Wanda; Beagley, Janet C; Urazova, Olga Y; Breiman, Robert F; Rupprecht, Charles E

    2008-04-01

    During lyssavirus surveillance, 1,221 bats of at least 30 species were collected from 25 locations in Kenya. One isolate of Lagos bat virus (LBV) was obtained from a dead Eidolon helvum fruit bat. The virus was most similar phylogenetically to LBV isolates from Senegal (1985) and from France (imported from Togo or Egypt; 1999), sharing with these viruses 100% nucleoprotein identity and 99.8 to 100% glycoprotein identity. This genome conservancy across space and time suggests that LBV is well adapted to its natural host species and that populations of reservoir hosts in eastern and western Africa have sufficient interactions to share pathogens. High virus concentrations, in addition to being detected in the brain, were detected in the salivary glands and tongue and in an oral swab, suggesting that LBV is transmitted in the saliva. In other extraneural organs, the virus was generally associated with innervations and ganglia. The presence of infectious virus in the reproductive tract and in a vaginal swab implies an alternative opportunity for transmission. The isolate was pathogenic for laboratory mice by the intracerebral and intramuscular routes. Serologic screening demonstrated the presence of LBV-neutralizing antibodies in E. helvum and Rousettus aegyptiacus fruit bats. In different colonies the seroprevalence ranged from 40 to 67% and 29 to 46% for E. helvum and R. aegyptiacus, respectively. Nested reverse transcription-PCR did not reveal the presence of viral RNA in oral swabs of bats in the absence of brain infection. Several large bat roosts were identified in areas of dense human populations, raising public health concerns for the potential of lyssavirus infection. PMID:18305130

  13. A recombinant rabies virus expressing vesicular stomatitis virus glycoprotein fails to protect against rabies virus infection

    PubMed Central

    Foley, Heather D.; McGettigan, James P.; Siler, Catherine A.; Dietzschold, Bernhard; Schnell, Matthias J.

    2000-01-01

    To investigate the importance of the rabies virus (RV) glycoprotein (G) in protection against rabies, we constructed a recombinant RV (rRV) in which the RV G ecto- and transmembrane domains were replaced with the corresponding regions of vesicular stomatitis virus (VSV) glycoprotein (rRV-VSV-G). We were able to recover rRV-VSV-G and found that particle production was equal to rRV. However, the budding of the chimeric virus was delayed and infectious titers were reduced 10-fold compared with the parental rRV strain containing RV G. Biochemical analysis showed equal replication rates of both viruses, and similar amounts of wild-type and chimeric G were present in the respective viral particles. Additional studies were performed to determine whether the immune response against rRV-VSV-G was sufficient to protect against rabies. Mice were primed with rRV or rRV-VSV-G and challenged with a pathogenic strain of RV 12 days later. Similar immune responses against the internal viral proteins of both viruses indicated successful infection. All mice receiving the rRV vaccine survived the challenge, whereas immunization with rRV-VSV-G did not induce protection. The results confirm the crucial role of RV G in an RV vaccine. PMID:11114165

  14. Dominant resistance against plant viruses

    PubMed Central

    de Ronde, Dryas; Butterbach, Patrick; Kormelink, Richard

    2014-01-01

    To establish a successful infection plant viruses have to overcome a defense system composed of several layers. This review will overview the various strategies plants employ to combat viral infections with main emphasis on the current status of single dominant resistance (R) genes identified against plant viruses and the corresponding avirulence (Avr) genes identified so far. The most common models to explain the mode of action of dominant R genes will be presented. Finally, in brief the hypersensitive response (HR) and extreme resistance (ER), and the functional and structural similarity of R genes to sensors of innate immunity in mammalian cell systems will be described. PMID:25018765

  15. Household Transmission of Influenza Virus.

    PubMed

    Tsang, Tim K; Lau, Lincoln L H; Cauchemez, Simon; Cowling, Benjamin J

    2016-02-01

    Human influenza viruses cause regular epidemics and occasional pandemics with a substantial public health burden. Household transmission studies have provided valuable information on the dynamics of influenza transmission. We reviewed published studies and found that once one household member is infected with influenza, the risk of infection in a household contact can be up to 38%, and the delay between onset in index and secondary cases is around 3 days. Younger age was associated with higher susceptibility. In the future, household transmission studies will provide information on transmission dynamics, including the correlation of virus shedding and symptoms with transmission, and the correlation of new measures of immunity with protection against infection. PMID:26612500

  16. Oncogenic viruses and hepatocellular carcinoma.

    PubMed

    Ben Ari, Ziv; Weitzman, Ella; Safran, Michal

    2015-05-01

    About 80% of hepatocellular carcinoma (HCC) is caused by hepatitis B virus (HBV) and/or hepatitis C virus (HCV) infections especially in the setting of established cirrhosis or advanced fibrosis, making HCC prevention a major goal of antiviral therapy. HCC tumors are highly complex and heterogeneous resulting from the aberrant function of multiple molecular pathways. The roles of HCV or HBV in promoting HCC development are still either directly or indirectly are still speculative, but the evidence for both effects is compelling. In patients with chronic hepatitis viral infection, cirrhosis is not a prerequisite for tumorigenesis. PMID:25921667

  17. Development of high-yield influenza A virus vaccine viruses.

    PubMed

    Ping, Jihui; Lopes, Tiago J S; Nidom, Chairul A; Ghedin, Elodie; Macken, Catherine A; Fitch, Adam; Imai, Masaki; Maher, Eileen A; Neumann, Gabriele; Kawaoka, Yoshihiro

    2015-01-01

    Vaccination is one of the most cost-effective ways to prevent infection. Influenza vaccines propagated in cultured cells are approved for use in humans, but their yields are often suboptimal. Here, we screened A/Puerto Rico/8/34 (PR8) virus mutant libraries to develop vaccine backbones (defined here as the six viral RNA segments not encoding haemagglutinin and neuraminidase) that support high yield in cell culture. We also tested mutations in the coding and regulatory regions of the virus, and chimeric haemagglutinin and neuraminidase genes. A combination of high-yield mutations from these screens led to a PR8 backbone that improved the titres of H1N1, H3N2, H5N1 and H7N9 vaccine viruses in African green monkey kidney and Madin-Darby canine kidney cells. This PR8 backbone also improves titres in embryonated chicken eggs, a common propagation system for influenza viruses. This PR8 vaccine backbone thus represents an advance in seasonal and pandemic influenza vaccine development. PMID:26334134

  18. Bovine viral diarrhea virus: characteristics of the virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This paper reviews the history of research on bovine viral diarrhea viruses (BVDV) from their discovery in the 1940's to the design of current BVDV eradication programs. The physiochemical characteristics of BVDV are discussed and well as classification of BVDV into biotypes and genotypes. The trans...

  19. Development of high-yield influenza A virus vaccine viruses

    PubMed Central

    Ping, Jihui; Lopes, Tiago J.S.; Nidom, Chairul A.; Ghedin, Elodie; Macken, Catherine A.; Fitch, Adam; Imai, Masaki; Maher, Eileen A.; Neumann, Gabriele; Kawaoka, Yoshihiro

    2015-01-01

    Vaccination is one of the most cost-effective ways to prevent infection. Influenza vaccines propagated in cultured cells are approved for use in humans, but their yields are often suboptimal. Here, we screened A/Puerto Rico/8/34 (PR8) virus mutant libraries to develop vaccine backbones (defined here as the six viral RNA segments not encoding haemagglutinin and neuraminidase) that support high yield in cell culture. We also tested mutations in the coding and regulatory regions of the virus, and chimeric haemagglutinin and neuraminidase genes. A combination of high-yield mutations from these screens led to a PR8 backbone that improved the titres of H1N1, H3N2, H5N1 and H7N9 vaccine viruses in African green monkey kidney and Madin–Darby canine kidney cells. This PR8 backbone also improves titres in embryonated chicken eggs, a common propagation system for influenza viruses. This PR8 vaccine backbone thus represents an advance in seasonal and pandemic influenza vaccine development. PMID:26334134

  20. Peptide inhibitors of dengue virus and West Nile virus infectivity

    PubMed Central

    Hrobowski, Yancey M; Garry, Robert F; Michael, Scott F

    2005-01-01

    Viral fusion proteins mediate cell entry by undergoing a series of conformational changes that result in virion-target cell membrane fusion. Class I viral fusion proteins, such as those encoded by influenza virus and human immunodeficiency virus (HIV), contain two prominent alpha helices. Peptides that mimic portions of these alpha helices inhibit structural rearrangements of the fusion proteins and prevent viral infection. The envelope glycoprotein (E) of flaviviruses, such as West Nile virus (WNV) and dengue virus (DENV), are class II viral fusion proteins comprised predominantly of beta sheets. We used a physio-chemical algorithm, the Wimley-White interfacial hydrophobicity scale (WWIHS) [1] in combination with known structural data to identify potential peptide inhibitors of WNV and DENV infectivity that target the viral E protein. Viral inhibition assays confirm that several of these peptides specifically interfere with target virus entry with 50% inhibitory concentration (IC50) in the 10 μM range. Inhibitory peptides similar in sequence to domains with a significant WWIHS scores, including domain II (IIb), and the stem domain, were detected. DN59, a peptide corresponding to the stem domain of DENV, inhibited infection by DENV (>99% inhibition of plaque formation at a concentrations of <25 μM) and cross-inhibition of WNV fusion/infectivity (>99% inhibition at <25 μM) was also demonstrated with DN59. However, a potent WNV inhibitory peptide, WN83, which corresponds to WNV E domain IIb, did not inhibit infectivity by DENV. Additional results suggest that these inhibitory peptides are noncytotoxic and act in a sequence specific manner. The inhibitory peptides identified here can serve as lead compounds for the development of peptide drugs for flavivirus infection. PMID:15927084

  1. Influenza virus activation of the interferon system

    PubMed Central

    Killip, Marian J.; Fodor, Ervin; Randall, Richard E.

    2015-01-01

    The host interferon (IFN) response represents one of the first barriers that influenza viruses must surmount in order to establish an infection. Many advances have been made in recent years in understanding the interactions between influenza viruses and the interferon system. In this review, we summarise recent work regarding activation of the type I IFN response by influenza viruses, including attempts to identify the viral RNA responsible for IFN induction, the stage of the virus life cycle at which it is generated and the role of defective viruses in this process. PMID:25678267

  2. Innate Immunity and BK Virus: Prospective Strategies.

    PubMed

    Kariminik, Ashraf; Yaghobi, Ramin; Dabiri, Shahriar

    2016-03-01

    Recent information demonstrated that BK virus reactivation is a dominant complication after kidney transplantation, which occurs because of immunosuppression. BK virus reactivation is the main reason of transplanted kidney losing. Immune response against BK virus is the major inhibitor of the virus reactivation. Therefore, improving our knowledge regarding the main parameters that fight against BK viruses can shed light on to direct new treatment strategies to suppress BK infection. Innate immunity consists of numerous cell systems and also soluble molecules, which not only suppress virus replication, but also activate adaptive immunity to eradicate the infection. Additionally, it appears that immune responses against reactivated BK virus are the main reasons for induction of BK virus-associated nephropathy (BKAN). Thus, improving our knowledge regarding the parameters and detailed mechanisms of innate immunity and also the status of innate immunity of the patients with BK virus reactivation and its complications can introduce new prospective strategies to either prevent or as therapy of the complication. Therefore, this review was aimed to collate the most recent data regarding the roles played by innate immunity against BK virus and also the status of innate immunity in the patients with reactivation BK virus and BKAN. PMID:26752693

  3. Comparative analysis of chrysanthemum transcriptome in response to three RNA viruses: Cucumber mosaic virus, Tomato spotted wilt virus and Potato virus X.

    PubMed

    Choi, Hoseong; Jo, Yeonhwa; Lian, Sen; Jo, Kyoung-Min; Chu, Hyosub; Yoon, Ju-Yeon; Choi, Seung-Kook; Kim, Kook-Hyung; Cho, Won Kyong

    2015-06-01

    The chrysanthemum is one of popular flowers in the world and a host for several viruses. So far, molecular interaction studies between the chrysanthemum and viruses are limited. In this study, we carried out a transcriptome analysis of chrysanthemum in response to three different viruses including Cucumber mosaic virus (CMV), Tomato spotted wilt virus (TSWV) and Potato virus X (PVX). A chrysanthemum 135K microarray derived from expressed sequence tags was successfully applied for the expression profiles of the chrysanthemum at early stage of virus infection. Finally, we identified a total of 125, 70 and 124 differentially expressed genes (DEGs) for CMV, TSWV and PVX, respectively. Many DEGs were virus specific; however, 33 DEGs were commonly regulated by three viruses. Gene ontology (GO) enrichment analysis identified a total of 132 GO terms, and of them, six GO terms related stress response and MCM complex were commonly identified for three viruses. Several genes functioning in stress response such as chitin response and ethylene mediated signaling pathway were up-regulated indicating their involvement in establishment of host immune system. In particular, TSWV infection significantly down-regulated genes related to DNA metabolic process including DNA replication, chromatin organization, histone modification and cytokinesis, and they are mostly targeted to nucleosome and MCM complex. Taken together, our comparative transcriptome analysis revealed several genes related to hormone mediated viral stress response and DNA modification. The identified chrysanthemums genes could be good candidates for further functional study associated with resistant to various plant viruses. PMID:25904110

  4. Persistence of virus lipid signatures upon silicification

    NASA Astrophysics Data System (ADS)

    Kyle, J.; Jahnke, L. L.; Stedman, K. M.

    2011-12-01

    To date there is no known evidence of viruses within the rock record. Their small size and absence of a metabolism has led to the hypothesis that they lack unique biological signatures, and the potential to become preserved. Biosignature research relevant to early Earth has focused on prokaryotic communities; however, the most abundant member of modern ecosystems, viruses, have been ignored. In order to establish a baseline for research on virus biosignatures, we have initiated laboratory research on known lipid-containing viruses. PRD1 is a lipid-containing virus that infects and replicates in Salmonella typhimurium LT2. PRD1 is a 65 nm spherical virus with an internal lipid membrane, which is a few nanometers thick. When the PRD1 virus stock was mixed with a 400 ppm SiO2 (final concentration) solution and incubated for six months. Fourier Transform Infrared Spectroscopy and lipid analysis using gas chromatography revealed that the virus lipids were still detectable despite complete removal of dissolved silica. Free fatty acids were also detected. Titers of infectious PRD1 viruses after six months in the presence of silica decreased 40 times more than without silica. Though virus biosignature research is in its incipient stages, the data suggest that virus lipid signatures are preserved under laboratory conditions and may offer the potential for contribution to the organic geochemical record.

  5. Human viruses in sediments, sludges, and soils*

    PubMed Central

    Rao, V. Chalapati; Metcalf, Theodore G.; Melnick, Joseph L.

    1986-01-01

    Recent studies have provided a greater understanding of the movement of viruses in the environment by their attachment to solids. These studies have focused on solids-associated viruses present in wastewater discharged into the ocean and on viruses in sludge and wastewater that may be retained in soil following their land disposal. Such ocean or land disposal of wastewater and sludge may result in a discharge of one or more of 120 human enteric virus pathogens including those causing poliomyelitis, viral hepatitis A and acute gastroenteritis. Solids-associated viruses in effluents discharged into coastal waters accumulate in bottom sediments, which may contain 10 to 10 000 more virus per unit volume than the overlying seawater. Solids-associated viruses resuspended by water turbulence may be transported from polluted to distant non-polluted recreational or shellfish-growing water. Transmission of viruses causing hepatitis or gastroenteritis may result from contact by bathers or swimmers with these viruses in recreational waters, or from ingestion of raw or improperly cooked shellfish in which the solids-associated virus had been bioaccumulated. The land disposal of sludge and wastewater has a potential of causing infections in farm workers, contamination of crops, pollution of raw potable water sources or infiltration of ground water. Viruses retained on soils can be released by rain water and may contaminate ground water through lateral and vertical movements. PMID:3015442

  6. Method for detecting viruses in aerosols.

    PubMed

    Wallis, C; Melnick, J L; Rao, V C; Sox, T E

    1985-11-01

    A simple method with poliovirus as the model was developed for recovering human enteric viruses from aerosols. Filterite filters (pore size, 0.45 micron; Filterite Corp., Timonium, Md.) moistened with glycine buffer (pH 3.5) were used for adsorbing the aerosolized virus. No virus passed the filter, even with air flow rates of 100 liters/min. Virus recovery from the filter was achieved by rapid elution with 800 ml of glycine buffer, pH 10. The virus in the primary eluate was reconcentrated by adjusting the pH to 3.5, adding AlCl3 to 0.0005 M, collecting the virus on a 0.25-micron-pore Filerite disk (diameter, 25 mm) and and eluting with 6 ml of buffer, pH 10. With this method, virus could be detected regularly in aerosols produced by flushing when 3 X 10(8) PFU of poliovirus were present in the toilet bowl. Poliovirus-containing fecal material from two of four infants who had recently received oral polio vaccine also yielded virus in the aerosols when feces containing 2.4 X 10(7) to 4.5 X 10(7) PFU of virus had been added to the toilet bowl. Persons infected with a variety of natural enteric viruses are known to excrete this amount of virus in their daily stools. PMID:3004329

  7. Method for detecting viruses in aerosols.

    PubMed Central

    Wallis, C; Melnick, J L; Rao, V C; Sox, T E

    1985-01-01

    A simple method with poliovirus as the model was developed for recovering human enteric viruses from aerosols. Filterite filters (pore size, 0.45 micron; Filterite Corp., Timonium, Md.) moistened with glycine buffer (pH 3.5) were used for adsorbing the aerosolized virus. No virus passed the filter, even with air flow rates of 100 liters/min. Virus recovery from the filter was achieved by rapid elution with 800 ml of glycine buffer, pH 10. The virus in the primary eluate was reconcentrated by adjusting the pH to 3.5, adding AlCl3 to 0.0005 M, collecting the virus on a 0.25-micron-pore Filerite disk (diameter, 25 mm) and and eluting with 6 ml of buffer, pH 10. With this method, virus could be detected regularly in aerosols produced by flushing when 3 X 10(8) PFU of poliovirus were present in the toilet bowl. Poliovirus-containing fecal material from two of four infants who had recently received oral polio vaccine also yielded virus in the aerosols when feces containing 2.4 X 10(7) to 4.5 X 10(7) PFU of virus had been added to the toilet bowl. Persons infected with a variety of natural enteric viruses are known to excrete this amount of virus in their daily stools. Images PMID:3004329

  8. A Literature Review of Zika Virus

    PubMed Central

    Bloch, Evan M.

    2016-01-01

    Zika virus is a mosquitoborne flavivirus that is the focus of an ongoing pandemic and public health emergency. Previously limited to sporadic cases in Africa and Asia, the emergence of Zika virus in Brazil in 2015 heralded rapid spread throughout the Americas. Although most Zika virus infections are characterized by subclinical or mild influenza-like illness, severe manifestations have been described, including Guillain-Barre syndrome in adults and microcephaly in babies born to infected mothers. Neither an effective treatment nor a vaccine is available for Zika virus; therefore, the public health response primarily focuses on preventing infection, particularly in pregnant women. Despite growing knowledge about this virus, questions remain regarding the virus’s vectors and reservoirs, pathogenesis, genetic diversity, and potential synergistic effects of co-infection with other circulating viruses. These questions highlight the need for research to optimize surveillance, patient management, and public health intervention in the current Zika virus epidemic. PMID:27070380

  9. Vulnerability of unconfined aquifers to virus contamination.

    PubMed

    Schijven, J F; Hassanizadeh, S Majid; de Roda Husman, Ana Maria

    2010-02-01

    An empirical formula was developed for determining the vulnerability of unconfined sandy aquifers to virus contamination, expressed as a dimensionless setback distance r(s)(*). The formula can be used to calculate the setback distance required for the protection of drinking water production wells against virus contamination. This empirical formula takes into account the intrinsic properties of the virus and the unconfined sandy aquifer. Virus removal is described by a rate coefficient that accounts for virus inactivation and attachment to sand grains. The formula also includes pumping rate, saturated thickness of the aquifer, depth of the screen of the pumping well, and anisotropy of the aquifer. This means that it accounts also for dilution effects as well as horizontal and vertical virus transport. Because the empirical model includes virus source concentration it can be used as an integral part of a quantitative viral risk assessment. PMID:20110099

  10. The semipermeability of simple spherical virus capsids.

    PubMed

    Durham, A C; Witz, J; Bancroft, J B

    1984-02-01

    Hydrogen-ion titration curves are reported for tomato bushy stunt virus, two strains of cowpea chlorotic mottle virus, and turnip crinkle virus, with particular attention to the hysteresis loops associated with the swelling and contraction of virions. There appears to be an archetypal shape of hysteresis loops, which is shared by viruses in several groups, suggestive of many intermediate states in the swelling of any one particle. In contrast, eggplant mosaic virus behaves as if its protein capsid is impermeable to small ions in mild conditions; its cation-binding sites were revealed by treatment with high concentrations of salt or urea, or at raised temperatures. Putting these observations together with the fact that a spherical virus capsid is a closed, holey, charged surface leads to a theory of titration hysteresis: its key feature is that the protein capsids of simple viruses are inherently semipermeable, with many of the ion-handling properties usually attributed only to complex lipid membranes. PMID:18639804

  11. Systems analysis of West Nile virus infection.

    PubMed

    Suthar, Mehul S; Pulendran, Bali

    2014-06-01

    Emerging and re-emerging mosquito-borne viruses continue to pose a significant threat to human health throughout the world. Over the past decade, West Nile virus (WNV), Dengue virus (DENV), and Chikungunya virus (CHIKV), have caused annual epidemics of virus-induced encephalitis, hemorrhagic fever\\shock syndromes, and arthritis, respectively. Currently, no specific antiviral therapies or vaccines exist for use in humans to combat or prevent these viral infections. Thus, there is a pressing need to define the virus-host interactions that govern immunity and infection outcome. Recent technological breakthroughs in 'omics' resources and high-throughput based assays are beginning to accelerate antiviral drug discovery and improve on current strategies for vaccine design. In this review, we highlight studies with WNV and discuss how traditional and systems biological approaches are being used to rapidly identify novel host targets for therapeutic intervention and develop a deeper conceptual understanding of the host response to virus infection. PMID:24851811

  12. [Persistence of bacteria and viruses in Ixodes].

    PubMed

    Podboronov, V M; Smirnova, I P

    2014-01-01

    Behaviour of viruses and salmonellas in ticks after their single or combined contamination was thoroughly studied on laboratory animals with bacteriemia or virusemia. When Ixodes ricinus was contaminated simultaneously with forest-spring encephalitis virus and salmonellas there were observed a decrease in the virus titer by the 30th-40th days and its death in 60 days. In case of the I. ricinus nymphs contamination, the virus titer after the combined contamination was by a factor of 10(2) lower in 60 days vs. the contamination with the virus alone and did not reach the contamination dose. The simultaneous contamination of the ticks with two pathogens (forest-spring encephalitis virus and salmonellas) resulted in inhibition of the growth and development of both the virus and the salmonellas. PMID:25975109

  13. Hot crenarchaeal viruses reveal deep evolutionary connections.

    PubMed

    Ortmann, Alice C; Wiedenheft, Blake; Douglas, Trevor; Young, Mark

    2006-07-01

    The discovery of archaeal viruses provides insights into the fundamental biochemistry and evolution of the Archaea. Recent studies have identified a wide diversity of archaeal viruses within the hot springs of Yellowstone National Park and other high-temperature environments worldwide. These viruses are often morphologically unique and code for genes with little similarity to other known genes in the biosphere, a characteristic that has complicated efforts to trace their evolutionary history. Comparative genomics combined with structural analysis indicate that spindle-shaped virus lineages might be unique to the Archaea, whereas other icosahedral viruses might share a common lineage with viruses of Bacteria and Eukarya. These studies provide insights into the evolutionary history of viruses in all three domains of life. PMID:16755285

  14. Microcephaly and the Zika virus.

    PubMed

    2016-09-12

    Cases of microcephaly brought about by the Zika virus have brought professional and personal challenges for nurses in Brazil. Paediatric nurses, such as Roberta Seabra (pictured), take over as part of the multidisciplinary team once the baby is born. In this article health writer Jacqui Thornton presents some personal stories. PMID:27615590

  15. Turnip Yellow Mosaic Virus Structure

    NASA Technical Reports Server (NTRS)

    2000-01-01

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

  16. New vaccines against influenza virus

    PubMed Central

    Lee, Young-Tae; Kim, Ki-Hye; Ko, Eun-Ju; Lee, Yu-Na; Kim, Min-Chul; Kwon, Young-Man; Tang, Yinghua; Cho, Min-Kyoung; Lee, Youn-Jeong

    2014-01-01

    Vaccination is one of the most effective and cost-benefit interventions that prevent the mortality and reduce morbidity from infectious pathogens. However, the licensed influenza vaccine induces strain-specific immunity and must be updated annually based on predicted strains that will circulate in the upcoming season. Influenza virus still causes significant health problems worldwide due to the low vaccine efficacy from unexpected outbreaks of next epidemic strains or the emergence of pandemic viruses. Current influenza vaccines are based on immunity to the hemagglutinin antigen that is highly variable among different influenza viruses circulating in humans and animals. Several scientific advances have been endeavored to develop universal vaccines that will induce broad protection. Universal vaccines have been focused on regions of viral proteins that are highly conserved across different virus subtypes. The strategies of universal vaccines include the matrix 2 protein, the hemagglutinin HA2 stalk domain, and T cell-based multivalent antigens. Supplemented and/or adjuvanted vaccination in combination with universal target antigenic vaccines would have much promise. This review summarizes encouraging scientific advances in the field with a focus on novel vaccine designs. PMID:24427759

  17. Virus diffusion in isolation rooms.

    PubMed

    Kao, P H; Yang, R J

    2006-03-01

    In hospitals, the ventilation of isolation rooms operating under closed-door conditions is vital if the spread of viruses and infection is to be contained. Engineering simulation, which employs computational fluid dynamics, provides a convenient means of investigating airflow behaviour in isolation rooms for various ventilation arrangements. A cough model was constructed to permit the numerical simulation of virus diffusion inside an isolation room for different ventilation system configurations. An analysis of the region of droplet fallout and the dilution time of virus diffusion of coughed gas in the isolation room was also performed for each ventilation arrangement. The numerical results presented in this paper indicate that the parallel-directional airflow pattern is the most effective means of controlling flows containing virus droplets. Additionally, staggering the positions of the supply vents at the door end of the room relative to the exhaust vents on the wall behind the bed head provides effective infection control and containment. These results suggest that this particular ventilation arrangement enhances the safety of staff when performing medical treatments within isolation rooms. PMID:16359753

  18. Satellite Tobacco Mosaic Virus (STMV)

    NASA Technical Reports Server (NTRS)

    2000-01-01

    The structure of the Satellite Tobacco Mosaic Virus (STMV)--one of the smallest viruses known--has been successfully deduced using STMV crystals grown aboard the Space Shuttle in 1992 and 1994. The STMV crystals were up to 30 times the volume of any seen in the laboratory. At the same time they gave the best resolution data ever obtained on any virus crystal. STMV is a small icosahedral plant virus, consisting of a protein shell made up of 60 identical protein subunits of molecular weight 17,500. Particularly noteworthy is the fact that, in contrast to the crystal grown on Earth, the crystals grown under microgravity conditions were viusally perfect, with no striations or clumping of crystals. Furthermore, the X-ray diffraction data obtained from the space-grown crystals was of a much higher quality than the best data available at that time from ground-based crystals. This computer model shows the external coating or capsid. STMV is used because it is a simple protein to work with; studies are unrelated to tobacco. Credit: Dr. Alex McPherson, Univeristy of California at Irvin.

  19. Enumerating viruses in coral mucus.

    PubMed

    Leruste, Amandine; Bouvier, Thierry; Bettarel, Yvan

    2012-09-01

    The distribution of viruses inhabiting the coral mucus remains undetermined, as there is no suitable standardized procedure for their separation from this organic matrix, principally owing to its viscosity and autofluorescence. Seven protocols were tested, and the most efficient separations were obtained from a chemical treatment requiring potassium citrate. PMID:22729548

  20. Viruses Associated with Human Cancer

    PubMed Central

    McLaughlin-Drubin, Margaret E.; Munger, Karl

    2008-01-01

    It is estimated that viral infections contribute to 15–20% of all human cancers. As obligatory intracellular parasites, viruses encode proteins that reprogram host cellular signaling pathways that control proliferation, differentiation, cell death, genomic integrity, and recognition by the immune system. These cellular processes are governed by complex and redundant regulatory networks and are surveyed by sentinel mechanisms that ensure that aberrant cells are removed from the proliferative pool. Given that the genome size of a virus is highly restricted to ensure packaging within an infectious structure, viruses must target cellular regulatory nodes with limited redundancy and need to inactivate surveillance mechanisms that would normally recognize and extinguish such abnormal cells. In many cases, key proteins in these same regulatory networks are subject to mutation in non-virally associated diseases and cancers. Oncogenic viruses have thus served as important experimental models to identify and molecularly investigate such cellular networks. These include the discovery of oncogenes and tumor suppressors, identification of regulatory networks that are critical for maintenance of genomic integrity, and processes that govern immune surveillance. PMID:18201576

  1. A virus-based biocatalyst

    NASA Astrophysics Data System (ADS)

    Carette, Noëlle; Engelkamp, Hans; Akpa, Eric; Pierre, Sebastien J.; Cameron, Neil R.; Christianen, Peter C. M.; Maan, Jan C.; Thies, Jens C.; Weberskirch, Ralf; Rowan, Alan E.; Nolte, Roeland J. M.; Michon, Thierry; van Hest, Jan C. M.

    2007-04-01

    Virus particles are probably the most precisely defined nanometre-sized objects that can be formed by protein self-assembly. Although their natural function is the storage and transport of genetic material, they have more recently been applied as scaffolds for mineralization and as containers for the encapsulation of inorganic compounds. The reproductive power of viruses has been used to develop versatile analytical methods, such as phage display, for the selection and identification of (bio)active compounds. To date, the combined use of self-assembly and reproduction has not been used for the construction of catalytic systems. Here we describe a self-assembled system based on a plant virus that has its coat protein genetically modified to provide it with a lipase enzyme. Using single-object and bulk catalytic studies, we prove that the virus-anchored lipase molecules are catalytically active. This anchored biocatalyst, unlike man-made supported catalysts, has the capability to reproduce itself in vivo, generating many independent catalytically active copies.

  2. Viruses, Mark Thy Message Well.

    PubMed

    Ye, Fengchun; Karn, Jonathan

    2016-05-11

    Post-transcriptional m(6)A methylation of RNA has profound effects on RNA splicing, export, stability, and translation. A recent study by Lichinchi et al. (2016) and one in this issue of Cell Host & Microbe by Kennedy et al. (2016) demonstrate that HIV mRNA is extensively m(6)A methylated, which promotes efficient virus replication. PMID:27173921

  3. A recombinant influenza virus vaccine expressing the F protein of respiratory syncytial virus

    PubMed Central

    Fonseca, Wendy; Ozawa, Makoto; Hatta, Masato; Orozco, Esther; Martínez, Máximo B; Kawaoka, Yoshihiro

    2014-01-01

    Infections with influenza and respiratory syncytial virus (RSV) rank high among the most common human respiratory diseases worldwide. Previously, we developed a replication-incompetent influenza virus by replacing the coding sequence of the PB2 gene, which encodes one of the viral RNA polymerase subunits, with that of a reporter gene. Here, we generated a PB2-knockout recombinant influenza virus expressing the F protein of RSV (PB2-RSVF virus) and tested its potential as a bivalent vaccine. In mice intranasally immunized with the PB2-RSVF virus, we detected high levels of antibodies against influenza virus, but not RSV. PB2-RSVF virus-immunized mice were protected from a lethal challenge with influenza virus but experienced severe body weight loss when challenged with RSV, indicating that PB2-RSVF vaccination enhanced RSV-associated disease. These results highlight one of the difficulties of developing an effective bivalent vaccine against influenza virus and RSV infections. PMID:24292020

  4. Psoralen inactivation of influenza and herpes simplex viruses and of virus-infected cells

    SciTech Connect

    Redfield, D.C.; Richman, D.D.; Oxman, M.N.; Kronenberg, L.H.

    1981-06-01

    Psoralen compounds covalently bind to nucleic acids when irradiated with long-wavelength ultraviolet light. This treatment can destroy the infectivity of deoxyribonucleic acid and ribonucleic acid viruses. Two psoralen compounds, 4'-hydroxymethyltrioxsalen and 4'-aminomethyltrioxsalen, were used with long-wavelength ultraviolet light to inactivate cell-free herpes simplex and influenza viruses and to render virus-infected cells noninfectious. This method of inactivation was compared with germicidal (short-wavelength) ultraviolet light irradiation. The antigenicity of the treated, virus-infected, antigen-bearing cells was examined by immunofluorescence and radioimmunoassay and by measuring the capacity of the herpes simplex virus-infected cells to stimulate virus-specific lymphocyte proliferation. The infectivity of the virus-infected cells could be totally eliminated without altering their viral antigenicity. The use of psoralen plus long-wavelength ultraviolet light is well suited to the preparation of noninfectious virus antigens and virus antigen-bearing cells for immunological assays.

  5. Rescue of rous sarcoma virus from rous sarcoma virus-transformed mammalian cells.

    PubMed

    Coffin, J M

    1972-07-01

    Rat cells transformed by the B77 strain of avian sarcoma virus produce no virus-like particles, yet B77 virus was rescued from these cells by Sendai virus-mediated fusion with chicken cells. This virus rescue was not affected by treatment of the chicken cells with agents that rendered the cells incapable of dividing, although such treatment greatly reduced the ability of the chicken cells to plate as infectious centers after infection with B77 virus. Fusion of R(B77) cells with chicken erythrocytes also led to virus rescue, although with less efficiency than fusion with chicken fibroblasts. Therefore, virus rescue was probably due to a factor or factors contributed by chicken cells which aid in virus production. PMID:4339192

  6. Status of tobacco viruses in Serbia and molecular characterization of tomato spotted wilt virus isolates.

    PubMed

    Stanković, I; Bulajić, A; Vučurović, A; Ristić, D; Milojević, K; Berenji, J; Krstić, B

    2011-01-01

    In a four-year survey to determine the presence and distribution of viruses in tobacco crops at 17 localities of the Vojvodina Province and Central Serbia, 380 samples were collected and analyzed by DAS-ELISA. Out of the seven viruses tested, tomato spotted wilt virus (TSWV), potato virus Y (PVY), tobacco mosaic virus (TMV), cucumber mosaic virus (CMV), and alfalfa mosaic virus (AMV) were detected in 37.9, 33.4, 28.7, 23.9, and 15.5% of the total tested samples, respectively. TSWV was the most frequently found virus at the localities of Central Serbia, while PVY and CMV were the most frequent viruses in the Vojvodina Province. Single infections were prevalent in years 2005-2007 and the most frequent were those of PVY. A triple combination of those viruses was most frequent mixed infection type in 2008. The presence of all five detected viruses was confirmed in selected ELISA-positive samples by RT-PCR and sequencing. The comparisons of obtained virus isolate sequences with those available in NCBI, confirmed the authenticity of serologically detected viruses. Phylogenetic analysis based on partial nucleocapsid gene sequences revealed a joint clustering of Serbian, Bulgarian and Montenegrin TSWV isolates into one geographic subpopulation, which was distinct from the other subpopulation of TSWV isolates from the rest of the European countries. The high incidence of viruses in Serbian tobacco crops highlights the importance of enhancing farmers knowledge towards better implementation of control strategies for preventing serious losses. PMID:22149499

  7. Top 10 plant viruses in molecular plant pathology.

    PubMed

    Scholthof, Karen-Beth G; Adkins, Scott; Czosnek, Henryk; Palukaitis, Peter; Jacquot, Emmanuel; Hohn, Thomas; Hohn, Barbara; Saunders, Keith; Candresse, Thierry; Ahlquist, Paul; Hemenway, Cynthia; Foster, Gary D

    2011-12-01

    Many scientists, if not all, feel that their particular plant virus should appear in any list of the most important plant viruses. However, to our knowledge, no such list exists. The aim of this review was to survey all plant virologists with an association with Molecular Plant Pathology and ask them to nominate which plant viruses they would place in a 'Top 10' based on scientific/economic importance. The survey generated more than 250 votes from the international community, and allowed the generation of a Top 10 plant virus list for Molecular Plant Pathology. The Top 10 list includes, in rank order, (1) Tobacco mosaic virus, (2) Tomato spotted wilt virus, (3) Tomato yellow leaf curl virus, (4) Cucumber mosaic virus, (5) Potato virus Y, (6) Cauliflower mosaic virus, (7) African cassava mosaic virus, (8) Plum pox virus, (9) Brome mosaic virus and (10) Potato virus X, with honourable mentions for viruses just missing out on the Top 10, including Citrus tristeza virus, Barley yellow dwarf virus, Potato leafroll virus and Tomato bushy stunt virus. This review article presents a short review on each virus of the Top 10 list and its importance, with the intent of initiating discussion and debate amongst the plant virology community, as well as laying down a benchmark, as it will be interesting to see in future years how perceptions change and which viruses enter and leave the Top 10. PMID:22017770

  8. Full Genome Characterization of the Culicoides-Borne Marsupial Orbiviruses: Wallal Virus, Mudjinbarry Virus and Warrego Viruses

    PubMed Central

    Belaganahalli, Manjunatha N.; Maan, Sushila; Maan, Narender S.; Pritchard, Ian; Kirkland, Peter D.; Brownlie, Joe; Attoui, Houssam; Mertens, Peter P. C.

    2014-01-01

    Viruses belonging to the species Wallal virus and Warrego virus of the genus Orbivirus were identified as causative agents of blindness in marsupials in Australia during 1994/5. Recent comparisons of nucleotide (nt) and amino acid (aa) sequences have provided a basis for the grouping and classification of orbivirus isolates. However, full-genome sequence data are not available for representatives of all Orbivirus species. We report full-genome sequence data for three additional orbiviruses: Wallal virus (WALV); Mudjinabarry virus (MUDV) and Warrego virus (WARV). Comparisons of conserved polymerase (Pol), sub-core-shell ‘T2’ and core-surface ‘T13’ proteins show that these viruses group with other Culicoides borne orbiviruses, clustering with Eubenangee virus (EUBV), another orbivirus infecting marsupials. WARV shares <70% aa identity in all three conserved proteins (Pol, T2 and T13) with other orbiviruses, consistent with its classification within a distinct Orbivirus species. Although WALV and MUDV share <72.86%/67.93% aa/nt identity with other orbiviruses in Pol, T2 and T13, they share >99%/90% aa/nt identities with each other (consistent with membership of the same virus species - Wallal virus). However, WALV and MUDV share <68% aa identity in their larger outer capsid protein VP2(OC1), consistent with membership of different serotypes within the species - WALV-1 and WALV-2 respectively. PMID:25299687

  9. Yellow fever vector live-virus vaccines: West Nile virus vaccine development.

    PubMed

    Arroyo, J; Miller, C A; Catalan, J; Monath, T P

    2001-08-01

    By combining molecular-biological techniques with our increased understanding of the effect of gene sequence modification on viral function, yellow fever 17D, a positive-strand RNA virus vaccine, has been manipulated to induce a protective immune response against viruses of the same family (e.g. Japanese encephalitis and dengue viruses). Triggered by the emergence of West Nile virus infections in the New World afflicting humans, horses and birds, the success of this recombinant technology has prompted the rapid development of a live-virus attenuated candidate vaccine against West Nile virus. PMID:11516995

  10. Clarification and guidance on the proper usage of virus and virus species names

    PubMed Central

    Jahrling, Peter B.

    2010-01-01

    A pivotal step in the development of a consistent nomenclature for virus classification was the introduction of the virus species concept by the International Committee on Taxonomy of Viruses (ICTV) in 1991. Yet, almost two decades later, many virologists still are unable to differentiate between virus species and actual viruses. Here we attempt to explain the origin of this confusion, clarify the difference between taxa and physical entities, and suggest simple measures that could be implemented by ICTV Study Groups to make virus taxonomy and nomenclature more accessible to laboratory virologists. PMID:20204430

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

    SciTech Connect

    Straus, S.E. )

    1989-12-01

    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.

  12. Virus-Specific Cellular Response in Hepatitis C Virus Infection.

    PubMed

    Kaźmierczak, Justyna; Caraballo Cortes, Kamila; Bukowska-Ośko, Iwona; Radkowski, Marek

    2016-04-01

    Studies performed on chimpanzees and humans have revealed that strong, multispecific and sustained CD4(+) and CD8(+) T cell immune responses is a major determinant of hepatitis C virus (HCV) clearance. However, spontaneous elimination of the virus occurs in minority of infected individuals and cellular response directed against HCV antigens is not persistent in individuals with chronic infection. This review presents characteristics of the HCV-specific T cell response in patients with different clinical course of infection, including acute and chronic infection, persons who spontaneously eliminated HCV and non-infected subjects exposed to HCV. Detection of HCV-specific response, especially in non-infected subjects exposed to HCV, may be indicative of HCV prevalence in population and rate of spontaneous viral clearance. Understanding the mechanisms and role of HCV-specific cellular immune response would contribute to better understanding of HCV epidemiology, immunopathogenesis and may help to design an effective vaccine. PMID:26429740

  13. 9 CFR 113.206 - Wart Vaccine, Killed Virus.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Wart Vaccine, Killed Virus. 113.206... AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.206 Wart Vaccine, Killed Virus. Wart Vaccine, Killed Virus, shall be...

  14. 9 CFR 113.206 - Wart Vaccine, Killed Virus.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Wart Vaccine, Killed Virus. 113.206... AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.206 Wart Vaccine, Killed Virus. Wart Vaccine, Killed Virus, shall be...

  15. 9 CFR 113.206 - Wart Vaccine, Killed Virus.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Wart Vaccine, Killed Virus. 113.206... AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.206 Wart Vaccine, Killed Virus. Wart Vaccine, Killed Virus, shall be...

  16. 9 CFR 113.206 - Wart Vaccine, Killed Virus.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Wart Vaccine, Killed Virus. 113.206... AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.206 Wart Vaccine, Killed Virus. Wart Vaccine, Killed Virus, shall be...

  17. 9 CFR 113.206 - Wart Vaccine, Killed Virus.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Wart Vaccine, Killed Virus. 113.206... AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.206 Wart Vaccine, Killed Virus. Wart Vaccine, Killed Virus, shall be...

  18. Blueberry latent virus: An Amalgam of the Totiviridae and Partitiviridae

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A new, symptomless virus was identified in blueberry. The dsRNA genome of the virus, provisionally named Blueberry latent virus (BBLV), codes for two putative proteins and lacks a movement protein, a property only shared with cryptic viruses. More than 35 isolates of the virus from different cultiv...

  19. Genetic mechanisms of Maize dwarf mosaic virus resistance in maize

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Maize resistance to viruses has been well-characterized at the genetic level, and loci responsible for resistance to potyviruses including Maize dwarf mosaic virus (MDMV), Sugarcane mosaic virus (SCMV), Sorghum mosaic virus (SrMV), and Johnsongrass mosaic virus (JGMV), have been mapped in several ge...

  20. IFITMs restrict the replication of multiple pathogenic viruses

    PubMed Central

    Perreira, Jill M.; Chin, Christopher R.; Feeley, Eric M.; Brass, Abraham L.

    2014-01-01

    The IFITM family of proteins inhibit a growing number of pathogenic viruses, among them influenza A virus, dengue virus, hepatitis C virus, and Ebola virus. This review covers recent developments in our understanding of the IFITM’s molecular determinants, potential mechanisms of action, and impact on pathogenesis. PMID:24076421

  1. [Epidemiological characteristics of Zika virus disease].

    PubMed

    Li, Jiandong; Li, Dexin

    2016-03-01

    Zika virus disease is an emerging mosquito-borne acute infectious disease caused by Zika virus, so far there have been no available vaccine or specific treatment. Currently, the outbreaks of Zika virus disease mainly occurs in the Americas, but the regional distribution of the disease is in rapid expansion, 34 countries and territories have reported autochthonous transmission of the virus. The illness is usually mild with very rarely death, but increased reports of birth defects and neurologic disorders in the areas affected by Zika virus has caused extensive concern worldwide. In China, the competent vectors for Zika virus are widely distributed, imported viraemic cases may become a source of local transmission of the virus. However, Zika virus disease is preventable, the spread of virus could be stopped when the effective prevention measures are taken. This paper summarizes the retrieval results from Medline database and the information from the reports of the governments of countries affected or health organizations about the epidemiological characteristics of Zika virus disease. PMID:27005530

  2. Pharmacological Inhibition of Feline Immunodeficiency Virus (FIV)

    PubMed Central

    Mohammadi, Hakimeh; Bienzle, Dorothee

    2012-01-01

    Feline immunodeficiency virus (FIV) is a member of the retroviridae family of viruses and causes an acquired immunodeficiency syndrome (AIDS) in domestic and non-domestic cats worldwide. Genome organization of FIV and clinical characteristics of the disease caused by the virus are similar to those of human immunodeficiency virus (HIV). Both viruses infect T lymphocytes, monocytes and macrophages, and their replication cycle in infected cells is analogous. Due to marked similarity in genomic organization, virus structure, virus replication and disease pathogenesis of FIV and HIV, infection of cats with FIV is a useful tool to study and develop novel drugs and vaccines for HIV. Anti-retroviral drugs studied extensively in HIV infection have targeted different steps of the virus replication cycle: (1) inhibition of virus entry into susceptible cells at the level of attachment to host cell surface receptors and co-receptors; (2) inhibition of fusion of the virus membrane with the cell membrane; (3) blockade of reverse transcription of viral genomic RNA; (4) interruption of nuclear translocation and viral DNA integration into host genomes; (5) prevention of viral transcript processing and nuclear export; and (6) inhibition of virion assembly and maturation. Despite much success of anti-retroviral therapy slowing disease progression in people, similar therapy has not been thoroughly investigated in cats. In this article we review current pharmacological approaches and novel targets for anti-lentiviral therapy, and critically assess potentially suitable applications against FIV infection in cats. PMID:22754645

  3. Recombination in Eukaryotic Single Stranded DNA Viruses

    PubMed Central

    Martin, Darren P.; Biagini, Philippe; Lefeuvre, Pierre; Golden, Michael; Roumagnac, Philippe; Varsani, Arvind

    2011-01-01

    Although single stranded (ss) DNA viruses that infect humans and their domesticated animals do not generally cause major diseases, the arthropod borne ssDNA viruses of plants do, and as a result seriously constrain food production in most temperate regions of the world. Besides the well known plant and animal-infecting ssDNA viruses, it has recently become apparent through metagenomic surveys of ssDNA molecules that there also exist large numbers of other diverse ssDNA viruses within almost all terrestrial and aquatic environments. The host ranges of these viruses probably span the tree of life and they are likely to be important components of global ecosystems. Various lines of evidence suggest that a pivotal evolutionary process during the generation of this global ssDNA virus diversity has probably been genetic recombination. High rates of homologous recombination, non-homologous recombination and genome component reassortment are known to occur within and between various different ssDNA virus species and we look here at the various roles that these different types of recombination may play, both in the day-to-day biology, and in the longer term evolution, of these viruses. We specifically focus on the ecological, biochemical and selective factors underlying patterns of genetic exchange detectable amongst the ssDNA viruses and discuss how these should all be considered when assessing the adaptive value of recombination during ssDNA virus evolution. PMID:21994803

  4. West Nile virus: North American experience

    USGS Publications Warehouse

    Hofmeister, Erik K.

    2011-01-01

    West Nile virus, a mosquito-vectored flavivirus of the Japanese encephalitis serogroup, was first detected in North America following an epizootic in the New York City area in 1999. In the intervening 11 years since the arrival of the virus in North America, it has crossed the contiguous USA, entered the Canadian provinces bordering the USA, and has been reported in the Caribbean islands, Mexico, Central America and, more recently, South America. West Nile virus has been reported in over 300 species of birds in the USA and has caused the deaths of thousands of birds, local population declines of some avian species, the clinical illness and deaths of thousands of domestic horses, and the clinical disease in over 30 000 Americans and the deaths of over 1000. Prior to the emergence of West Nile virus in North America, St. Louis encephalitis virus and Dengue virus were the only other known mosquito-transmitted flaviviruses in North America capable of causing human disease. This review will discuss the North American experience with mosquito-borne flavivirus prior to the arrival of West Nile virus, the entry and spread of West Nile virus in North America, effects on wild bird populations, genetic changes in the virus, and the current state of West Nile virus transmission.

  5. Occurrence of viruses infecting pea in Iran.

    PubMed

    Esfandiari, N; Kohi-Habibi, M; Mosahebi, Gh

    2006-01-01

    A survey was conducted to determine the incidence of Alfalfa mosaic virus (AMV), Bean yellow mosaic virus (BYMV), Broad bean wilt virus-1 (BBWV), Pea leafroll virus (PLRV), Pea enation mosaic virus (PEMV), Pea seed borne mosaic virus (PSbMV), Potato virus x(PVX), Tomato mosaic virus (ToMV), Tomato spotted wilt virus (TSWV) on pea (Pisum sativum) in Iran. A Total of 1276 random and 684 symptomatic pea samples were collected during the spring and summer of 2002-2004 in Tehran province of Iran, where pea is grown, and tested by enzyme-linked immunosorbent assay (ELISA) using specific polyclonal antibodies. Serological diagnoses were confirmed by electron microscopy and host range studies. Incidence of viruses in decreasing order was PVX (69%), ToMV (59%), PSbMV (36.6%), BBWV-1 (26.1%), BYMV (20.3%), AMV (17.77%), TSWV (12.6%), PEMV (10.9%), PLRV (6.78%). In this survey, natural occurrence of AMV, BBWV-1, PSbMV, TSWV, PVX and ToMV was reported for the first time on the pea in Iran. PMID:17390891

  6. Detection of Multiple Potato Viruses in the Field Suggests Synergistic Interactions among Potato Viruses in Pakistan.

    PubMed

    Hameed, Amir; Iqbal, Zafar; Asad, Shaheen; Mansoor, Shahid

    2014-12-01

    Viral diseases have been a major limiting factor threating sustainable potato (Solanum tuberosum L.) production in Pakistan. Surveys were conducted to serologically quantify the incidence of RNA viruses infecting potato; Potato virus X (PVX), Potato virus Y (PVY), Potato virus S (PVS), Potato virus A (PVA), Potato virus M (PVM) and Potato leaf roll virus (PLRV) in two major potato cultivars (Desiree and Cardinal). The results suggest the prevalence of multiple viruses in all surveyed areas with PVY, PVS and PVX dominantly widespread with infection levels of up to 50% in some regions. Co-infections were detected with the highest incidence (15.5%) for PVX and PVS. Additionally the data showed a positive correlation between co-infecting viruses with significant increase in absorbance value (virus titre) for at least one of the virus in an infected plant and suggested a synergistic interaction. To test this hypothesis, glasshouse grown potato plants were challenged with multiple viruses and analyzed for systemic infections and symptomology studies. The results obtained conclude that multiple viral infections dramatically increase disease epidemics as compared to single infection and an effective resistance strategy in targeting multiple RNA viruses is required to save potato crop. PMID:25506305

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

    SciTech Connect

    Burles, Kristin; Irwin, Chad R.; Burton, Robyn-Lee; Schriewer, Jill; Evans, David H.; Buller, R. Mark; Barry, Michele

    2014-05-15

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

  8. Herpes Simplex Virus and Varicella-Zoster Virus.

    PubMed

    Levin, Myron J; Weinberg, Adriana; Schmid, D Scott

    2016-06-01

    The most common specimens from immunocompromised patients that are analyzed for detection of herpes simplex virus (HSV) or varicella-zoster virus (VZV) are from skin lesions. Many types of assays are applicable to these samples, but some, such as virus isolation and direct fluorescent antibody testing, are useful only in the early phases of the lesions. In contrast, nucleic acid (NA) detection methods, which generally have superior sensitivity and specificity, can be applied to skin lesions at any stage of progression. NA methods are also the best choice, and sometimes the only choice, for detecting HSV or VZV in blood, cerebrospinal fluid, aqueous or vitreous humor, and from mucosal surfaces. NA methods provide the best performance when reliability and speed (within 24 hours) are considered together. They readily distinguish the type of HSV detected or the source of VZV detected (wild type or vaccine strain). Nucleic acid detection methods are constantly being improved with respect to speed and ease of performance. Broader applications are under study, such as the use of quantitative results of viral load for prognosis and to assess the efficacy of antiviral therapy. PMID:27337486

  9. Malsoor Virus, a Novel Bat Phlebovirus, Is Closely Related to Severe Fever with Thrombocytopenia Syndrome Virus and Heartland Virus

    PubMed Central

    Yadav, P. D.; Basu, A.; Shete, A.; Patil, D. Y.; Zawar, D.; Majumdar, T. D.; Kokate, P.; Sarkale, P.; Raut, C. G.; Jadhav, S. M.

    2014-01-01

    During a survey in the year 2010, a novel phlebovirus was isolated from the Rousettus leschenaultii species of bats in western India. The virus was identified by electron microscopy from infected Vero E6 cells. Phylogenic analysis of the complete genome showed its close relation to severe fever with thrombocytopenia syndrome (SFTS) and Heartland viruses, which makes it imperative to further study its natural ecology and potential as a novel emerging zoonotic virus. PMID:24390329

  10. 40 CFR 174.514 - Coat Protein of Watermelon Mosaic Virus-2 and Zucchini Yellow Mosaic Virus; exemption from the...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Virus-2 and Zucchini Yellow Mosaic Virus; exemption from the requirement for a tolerance. 174.514... Coat Protein of Watermelon Mosaic Virus-2 and Zucchini Yellow Mosaic Virus; exemption from the requirement for a tolerance. Residues of Coat Protein of Watermelon Mosaic Virus-2 and Zucchini Yellow...

  11. 40 CFR 174.514 - Coat Protein of Watermelon Mosaic Virus-2 and Zucchini Yellow Mosaic Virus; exemption from the...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Virus-2 and Zucchini Yellow Mosaic Virus; exemption from the requirement for a tolerance. 174.514... Coat Protein of Watermelon Mosaic Virus-2 and Zucchini Yellow Mosaic Virus; exemption from the requirement for a tolerance. Residues of Coat Protein of Watermelon Mosaic Virus-2 and Zucchini Yellow...

  12. 40 CFR 174.514 - Coat Protein of Watermelon Mosaic Virus-2 and Zucchini Yellow Mosaic Virus; exemption from the...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Virus-2 and Zucchini Yellow Mosaic Virus; exemption from the requirement for a tolerance. 174.514... Coat Protein of Watermelon Mosaic Virus-2 and Zucchini Yellow Mosaic Virus; exemption from the requirement for a tolerance. Residues of Coat Protein of Watermelon Mosaic Virus-2 and Zucchini Yellow...

  13. 40 CFR 174.514 - Coat Protein of Watermelon Mosaic Virus-2 and Zucchini Yellow Mosaic Virus; exemption from the...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Virus-2 and Zucchini Yellow Mosaic Virus; exemption from the requirement for a tolerance. 174.514... Coat Protein of Watermelon Mosaic Virus-2 and Zucchini Yellow Mosaic Virus; exemption from the requirement for a tolerance. Residues of Coat Protein of Watermelon Mosaic Virus-2 and Zucchini Yellow...

  14. 40 CFR 174.514 - Coat Protein of Watermelon Mosaic Virus-2 and Zucchini Yellow Mosaic Virus; exemption from the...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Virus-2 and Zucchini Yellow Mosaic Virus; exemption from the requirement for a tolerance. 174.514... Coat Protein of Watermelon Mosaic Virus-2 and Zucchini Yellow Mosaic Virus; exemption from the requirement for a tolerance. Residues of Coat Protein of Watermelon Mosaic Virus-2 and Zucchini Yellow...

  15. Evolution and ecology of influenza A viruses.

    PubMed Central

    Webster, R G; Bean, W J; Gorman, O T; Chambers, T M; Kawaoka, Y

    1992-01-01

    In this review we examine the hypothesis that aquatic birds are the primordial source of all influenza viruses in other species and study the ecological features that permit the perpetuation of influenza viruses in aquatic avian species. Phylogenetic analysis of the nucleotide sequence of influenza A virus RNA segments coding for the spike proteins (HA, NA, and M2) and the internal proteins (PB2, PB1, PA, NP, M, and NS) from a wide range of hosts, geographical regions, and influenza A virus subtypes support the following conclusions. (i) Two partly overlapping reservoirs of influenza A viruses exist in migrating waterfowl and shorebirds throughout the world. These species harbor influenza viruses of all the known HA and NA subtypes. (ii) Influenza viruses have evolved into a number of host-specific lineages that are exemplified by the NP gene and include equine Prague/56, recent equine strains, classical swine and human strains, H13 gull strains, and all other avian strains. Other genes show similar patterns, but with extensive evidence of genetic reassortment. Geographical as well as host-specific lineages are evident. (iii) All of the influenza A viruses of mammalian sources originated from the avian gene pool, and it is possible that influenza B viruses also arose from the same source. (iv) The different virus lineages are predominantly host specific, but there are periodic exchanges of influenza virus genes or whole viruses between species, giving rise to pandemics of disease in humans, lower animals, and birds. (v) The influenza viruses currently circulating in humans and pigs in North America originated by transmission of all genes from the avian reservoir prior to the 1918 Spanish influenza pandemic; some of the genes have subsequently been replaced by others from the influenza gene pool in birds. (vi) The influenza virus gene pool in aquatic birds of the world is probably perpetuated by low-level transmission within that species throughout the year. (vii

  16. Impact of anti-virus software on computer virus dynamical behavior

    NASA Astrophysics Data System (ADS)

    Sun, Mei; Li, Dandan; Han, Dun; Jia, Changsheng

    2014-11-01

    The impact of anti-virus software on the spreading of computer virus is investigated via developing a mathematical model in this paper. Considering the anti-virus software may not be effective, as it may be an outdated version, and then the computers may be infected with a reduced incidence rate. According to the method of next generation matrix, the basic reproduction number is derived. By introducing appropriate Lyapunov function and the Routh stability criterion, acquiring the stability conditions of the virus-free equilibrium and virus equilibrium. The effect of anti-virus software and disconnecting rate on the spreading of virus are also analyzed. When combined with the numerical results, a set of suggestions are put forward for eradicating virus effectively.

  17. Targeted Entry of Enveloped Viruses: Measles and Herpes Simplex Virus I

    PubMed Central

    Navaratnarajah, Chanakha K.; Miest, Tanner S.; Carfi, Andrea; Cattaneo, Roberto

    2011-01-01

    We compare the receptor-based mechanisms that a small RNA virus and a larger DNA virus have evolved to drive the fusion of viral and cellular membranes. Both systems rely on tight control over triggering the concerted refolding of a trimeric fusion protein. While measles virus entry depends on a receptor-binding protein and a fusion protein only, the herpes simplex virus is more complex and requires four viral proteins. Nevertheless, in both viruses a receptor-binding protein is required for triggering the membrane fusion process. Moreover, specificity domains can be appended to these receptor-binding proteins to target virus entry to cells expressing a designated receptor. We discuss how principles established with measles and herpes simplex virus can be applied to targeting other enveloped viruses, and alternatively how retargeted envelopes can be fitted on foreign capsids. PMID:22440965

  18. Spread of bovine virus diarrhoea virus in a herd of heifer calves.

    PubMed

    Wentink, G H; van Exsel, A C; de Goey, I; van Lieshout, J A

    1991-10-01

    A calf persistently infected and immunotolerant to Bovine Virus Diarrhoea virus (BVD virus) was, on purpose, introduced to a herd of heifer calves over 4 months of age that had been reared as recipients for embryo transplantation. All calves were brought in contact with the persistently infected animal. In total, 240 calves were involved in this experiment, 22 of which were serologically negative when introduced. These serologically negative animals developed antibodies against BVD virus within 5 months after introduction. At short distances from the persistently infected BVD virus shedder, negative calves seroconverted within 2 months, but at greater distances the moment of seroconversion was unpredictable. The calves that had undergone a natural infection with BVD virus received embryos after transportation to an allied farm. In total, 14 calves were born after embryo transplantation, all of which were free of BVD virus, in spite of the presence of BVD-virus on the latter farm. PMID:1663673

  19. Influenza A virus targets a cGAS-independent STING pathway that controls enveloped RNA viruses

    PubMed Central

    Holm, Christian K.; Rahbek, Stine H.; Gad, Hans Henrik; Bak, Rasmus O.; Jakobsen, Martin R.; Jiang, Zhaozaho; Hansen, Anne Louise; Jensen, Simon K.; Sun, Chenglong; Thomsen, Martin K.; Laustsen, Anders; Nielsen, Camilla G.; Severinsen, Kasper; Xiong, Yingluo; Burdette, Dara L.; Hornung, Veit; Lebbink, Robert Jan; Duch, Mogens; Fitzgerald, Katherine A.; Bahrami, Shervin; Mikkelsen, Jakob Giehm; Hartmann, Rune; Paludan, Søren R.

    2016-01-01

    Stimulator of interferon genes (STING) is known be involved in control of DNA viruses but has an unexplored role in control of RNA viruses. During infection with DNA viruses STING is activated downstream of cGAMP synthase (cGAS) to induce type I interferon. Here we identify a STING-dependent, cGAS-independent pathway important for full interferon production and antiviral control of enveloped RNA viruses, including influenza A virus (IAV). Further, IAV interacts with STING through its conserved hemagglutinin fusion peptide (FP). Interestingly, FP antagonizes interferon production induced by membrane fusion or IAV but not by cGAMP or DNA. Similar to the enveloped RNA viruses, membrane fusion stimulates interferon production in a STING-dependent but cGAS-independent manner. Abolishment of this pathway led to reduced interferon production and impaired control of enveloped RNA viruses. Thus, enveloped RNA viruses stimulate a cGAS-independent STING pathway, which is targeted by IAV. PMID:26893169

  20. Identification of Novel Viruses Using VirusHunter -- an Automated Data Analysis Pipeline

    PubMed Central

    Zhao, Guoyan; Krishnamurthy, Siddharth; Cai, Zhengqiu; Popov, Vsevolod L.; Travassos da Rosa, Amelia P.; Guzman, Hilda; Cao, Song; Virgin, Herbert W.; Tesh, Robert B.; Wang, David

    2013-01-01

    Quick and accurate identification of microbial pathogens is essential for both diagnosis and response to emerging infectious diseases. The advent of next-generation sequencing technology offers an unprecedented platform for rapid sequencing-based identification of novel viruses. We have developed a customized bioinformatics data analysis pipeline, VirusHunter, for the analysis of Roche/454 and other long read Next generation sequencing platform data. To illustrate the utility of VirusHunter, we performed Roche/454 GS FLX titanium sequencing on two unclassified virus isolates from the World Reference Center for Emerging Viruses and Arboviruses (WRCEVA). VirusHunter identified sequences derived from a novel bunyavirus and a novel reovirus in the two samples respectively. Further sequence analysis demonstrated that the viruses were novel members of the Phlebovirus and Orbivirus genera. Both Phlebovirus and Orbivirus genera include many economic important viruses or serious human pathogens. PMID:24167629

  1. Monitoring virus entry into living cells using DiD-labeled dengue virus particles.

    PubMed

    Ayala-Nuñez, Nilda V; Wilschut, Jan; Smit, Jolanda M

    2011-10-01

    A variety of approaches can be applied to investigate the multiple steps and interactions that occur during virus entry into the host cell. Single-virus tracking is a powerful real-time imaging technique that offers the possibility to monitor virus-cell binding, internalization, intracellular trafficking behavior, and the moment of membrane fusion of single virus particles in living cells. Here we describe the development and applications of a single-virus tracking assay based on the use of DiD-labeled dengue virus (DENV) in BS-C-1 cells. In addition - and using the same experimental setup - we present a binding and fusion assay that can be used to obtain a rapid insight into the relative extent of virus binding to the cell surface and membrane fusion. Details of virus labeling and characterization, microscopy setup, protocols, data analysis, and hints for troubleshooting are described throughout the paper. PMID:21855634

  2. Processing Strategies to Inactivate Enteric Viruses in Shellfish: Limitations of Surrogate Viruses and Molecular Methods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Noroviruses, hepatitis A and E viruses, sapovirus, astrovirus, rotavirus, Aichi virus, enteric adenoviruses, poliovirus, and other enteroviruses enter shellfish through contaminated seawater or by contamination during handling and processing, resulting in outbreaks ranging from isolated to epidemic....

  3. Full Genome Sequencing of Corriparta Virus, Identifies California Mosquito Pool Virus as a Member of the Corriparta virus Species

    PubMed Central

    Belaganahalli, Manjunatha N.; Maan, Sushila; Maan, Narender S.; Nomikou, Kyriaki; Guimera, Marc; Brownlie, Joe; Tesh, Robert; Attoui, Houssam; Mertens, Peter P. C.

    2013-01-01

    The species Corriparta virus (CORV), within the genus Orbivirus, family Reoviridae, currently contains six virus strains: corriparta virus MRM1 (CORV-MRM1); CS0109; V654; V370; Acado virus and Jacareacanga virus. However, lack of neutralization assays, or reference genome sequence data has prevented further analysis of their intra-serogroup/species relationships and identification of individual serotypes. We report whole-genome sequence data for CORV-MRM1, which was isolated in 1960 in Australia. Comparisons of the conserved, polymerase (VP1), sub-core-shell ‘T2’ and core-surface ‘T13’ proteins encoded by genome segments 1, 2 and 8 (Seg-1, Seg-2 and Seg-8) respectively, show that this virus groups with the other mosquito borne orbiviruses. However, highest levels of nt/aa sequence identity (75.9%/91.6% in Seg-2/T2: 77.6%/91.7% in Seg-8/T13, respectively) were detected between CORV-MRM1 and California mosquito pool virus (CMPV), an orbivirus isolated in the USA in 1974, showing that they belong to the same virus species. The data presented here identify CMPV as a member of the Corriparta virus species and will facilitate identification of additional CORV isolates, diagnostic assay design and epidemiological studies. PMID:24015178

  4. Detection of sweet potato virus C, sweet potato virus 2 and sweet potato feathery mottle virus in Portugal.

    PubMed

    Varanda, Carla M R; Santos, Susana J; Oliveira, Mônica D M; Clara, Maria Ivone E; Félix, Maria Rosário F

    2015-06-01

    Field sweet potato plants showing virus-like symptoms, as stunting, leaf distortion, mosaic and chlorosis, were collected in southwest Portugal and tested for the presence of four potyviruses, sweet potato virus C (SPVC), sweet potato virus 2 (SPV2), sweet potato feathery mottle virus (SPFMV), sweet potato virus G (SPVG), and the crinivirus sweet potato chlorotic stunt virus (SPCSV). DsRNA fractions were extracted from symptomatic leaves and used as templates in single and multiplex RT-PCR assays using previously described specific primers for each analyzed virus. The amplified reaction products for SPVC, SPV2 and SPFMV were of expected size, and direct sequencing of PCR products revealed that they correspond to the coat protein gene (CP) and showed 98%, 99% and 99% identity, respectively, to those viruses. Comparison of the CP genomic and amino acid sequences of the Portuguese viral isolates recovered here with those of ten other sequences of isolates obtained in different countries retrieved from the GenBank showed very few differences. The application of the RT-PCR assays revealed for the first time the presence of SPVC and SPFMV in the sweet potato crop in Portugal, the absence of SPVG and SPCSV in tested plants, as well as the occurrence of triple virus infections under field conditions. PMID:26104336

  5. Comparative analysis of rabbit hemorrhagic disease virus (RHDV) and new RHDV2 virus antigenicity, using specific virus-like particles.

    PubMed

    Bárcena, Juan; Guerra, Beatriz; Angulo, Iván; González, Julia; Valcárcel, Félix; Mata, Carlos P; Castón, José R; Blanco, Esther; Alejo, Alí

    2015-01-01

    In 2010 a new Lagovirus related to rabbit haemorrhagic disease virus (RHDV) emerged in France and has since rapidly spread throughout domestic and wild rabbit populations of several European countries. The new virus, termed RHDV2, exhibits distinctive genetic, antigenic and pathogenic features. Notably, RHDV2 kills rabbits previously vaccinated with RHDV vaccines. Here we report for the first time the generation and characterization of RHDV2-specific virus-like particles (VLPs). Our results further confirmed the differential antigenic properties exhibited by RHDV and RHDV2, highlighting the need of using RHDV2-specific diagnostic assays to monitor the spread of this new virus. PMID:26403184

  6. Zika virus challenges for neuropsychiatry

    PubMed Central

    Simões e Silva, Ana Cristina; Moreira, Janaina Matos; Romanelli, Roberta Maia Castro; Teixeira, Antonio Lucio

    2016-01-01

    Before 2007, Zika virus (ZIKV) was generally considered as an arbovirus of low clinical relevance, causing a mild self-limiting febrile illness in tropical Africa and Southeast Asia. Currently, a large, ongoing outbreak of ZIKV that started in Brazil in 2015 is spreading across the Americas. Virus infection during pregnancy has been potentially linked to congenital malformations, including microcephaly. In addition to congenital malformations, a temporal association between ZIKV infection and an increase in cases of Guillain–Barré syndrome is currently being observed in several countries. The mechanisms underlying these neurological complications are still unknown. Emerging evidence, mainly from in vitro studies, suggests that ZIKV may have direct effects on neuronal cells. The aim of this study was to critically review the literature available regarding the neurobiology of ZIKV and its potential neuropsychiatric manifestations. PMID:27478378

  7. Zika virus challenges for neuropsychiatry.

    PubMed

    Simões E Silva, Ana Cristina; Moreira, Janaina Matos; Romanelli, Roberta Maia Castro; Teixeira, Antonio Lucio

    2016-01-01

    Before 2007, Zika virus (ZIKV) was generally considered as an arbovirus of low clinical relevance, causing a mild self-limiting febrile illness in tropical Africa and Southeast Asia. Currently, a large, ongoing outbreak of ZIKV that started in Brazil in 2015 is spreading across the Americas. Virus infection during pregnancy has been potentially linked to congenital malformations, including microcephaly. In addition to congenital malformations, a temporal association between ZIKV infection and an increase in cases of Guillain-Barré syndrome is currently being observed in several countries. The mechanisms underlying these neurological complications are still unknown. Emerging evidence, mainly from in vitro studies, suggests that ZIKV may have direct effects on neuronal cells. The aim of this study was to critically review the literature available regarding the neurobiology of ZIKV and its potential neuropsychiatric manifestations. PMID:27478378

  8. Respiratory syncytial virus vaccine development

    PubMed Central

    Hurwitz, Julia L

    2011-01-01

    Respiratory syncytial virus (RSV) is the leading cause of lower respiratory tract viral disease in infants and young children. Presently, there are no explicit recommendations for RSV treatment apart from supportive care. The virus is therefore responsible for an estimated 160,000 deaths per year worldwide. Despite half a century of dedicated research, there remains no licensed vaccine product. Herein are described past and current efforts to harness innate and adaptive immune potentials to combat RSV. A plethora of candidate vaccine products and strategies are reviewed. The development of a successful RSV vaccine may ultimately stem from attention to historical lessons, in concert with an integral partnering of immunology and virology research fields. PMID:21988307

  9. Control of virus diseases of citrus.

    PubMed

    Lee, Richard F

    2015-01-01

    Citrus is thought to have originated in Southeast Asia and horticulturally desirable clonal selections have been clonally cultivated for hundreds of years. While some citrus species have nucellar embryony, most cultivation of citrus has been by clonal propagation to ensure that propagated plants have the same traits as the parent selection. Clonal propagation also avoids juvenility, and the propagated plants produce fruit sooner. Because of the clonal propagation of citrus, citrus has accumulated a large number of viruses; many of these viruses are asymptomatic until a susceptible rootstock and/or scion is encountered. The viruses reported to occur in citrus will be summarized in this review. Methods of therapy to clean selected clones from viruses will be reviewed; the use of quarantine, clean stock, and certification programs for control of citrus viruses and other strategies to control insect spread citrus viruses, such as mild strain cross-protection and the use of pest management areas will be discussed. PMID:25591879

  10. The ecology of emerging neurotropic viruses.

    PubMed

    Olival, Kevin J; Daszak, Peter

    2005-10-01

    The authors review common themes in the ecology of emerging viruses that cause neurological disease. Three issues emerge. First, 49% of emerging viruses are characterized by encephalitis or serious neurological clinical symptoms. Second, all of these viruses are driven to emerge by ecological, environmental, or human demographic changes, some of which are poorly understood. Finally, the control of these viruses would be enhanced by collaborative multidisciplinary research into these drivers of emergence. The authors highlight this review with a case study of Nipah virus, which emerged in Malaysia due largely to shifts in livestock production and alterations to reservoir host habitat. Collaboration between virologists, ecologists, disease modelers and wildlife biologists has been instrumental in retracing the factors involved in this virus's emergence. PMID:16287685

  11. No Love Lost Between Viruses and Interferons.

    PubMed

    Fensterl, Volker; Chattopadhyay, Saurabh; Sen, Ganes C

    2015-11-01

    The interferon system protects mammals against virus infections. There are several types of interferons, which are characterized by their ability to inhibit virus replication and resultant pathogenesis by triggering both innate and cell-mediated immune responses. Virus infection is sensed by a variety of cellular pattern-recognition receptors and triggers the synthesis of interferons, which are secreted by the infected cells. In uninfected cells, cell surface receptors recognize the secreted interferons and activate intracellular signaling pathways that induce the expression of interferon-stimulated genes; the proteins encoded by these genes inhibit different stages of virus replication. To avoid extinction, almost all viruses have evolved mechanisms to defend themselves against the interferon system. Consequently, a dynamic equilibrium of survival is established between the virus and its host, an equilibrium that can be shifted to the host's favor by the use of exogenous interferon as a therapeutic antiviral agent. PMID:26958928

  12. Study of virus by Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Moor, K.; Kitamura, H.; Hashimoto, K.; Sawa, M.; Andriana, B. B.; Ohtani, K.; Yagura, T.; Sato, H.

    2013-02-01

    Problem of viruses is very actual for nowadays. Some viruses, which are responsible for human of all tumors, are about 15 %. Main purposes this study, early detection virus in live cell without labeling and in the real time by Raman spectroscopy. Micro Raman spectroscopy (mRs) is a technique that uses a Raman spectrometer to measure the spectra of microscopic samples. According to the Raman spectroscopy, it becomes possible to study the metabolites of a live cultured cell without labeling. We used mRs to detect the virus via HEK 293 cell line-infected adenovirus. We obtained raman specters of lives cells with viruses in 24 hours and 7 days after the infection. As the result, there is some biochemical changing after the treatment of cell with virus. One of biochemical alteration is at 1081 cm-1. For the clarification result, we use confocal fluorescent microscopy and transmission electron microscopy (TEM).

  13. Fluorescence molecular painting of enveloped viruses.

    PubMed

    Metzner, Christoph; Kochan, Feliks; Dangerfield, John A

    2013-01-01

    In this study, we describe a versatile, flexible, and quick method to label different families of enveloped viruses with glycosylphosphatidylinositol-modified green fluorescent protein, termed fluorescence molecular painting (FMP). As an example for a potential application, we investigated virus attachment by means of flow cytometry to determine if viral binding behavior may be analyzed after FMP of enveloped viruses. Virus attachment was inhibited by using either dextran sulfate or by blocking attachment sites with virus pre-treatment. Results from the FMP-flow cytometry approach were verified by immunoblotting and enzyme-linked immunosorbent assay. Since the modification strategy is applicable to a broad range of proteins and viruses, variations of this method may be useful in a range of research and applied applications from bio-distribution studies to vaccine development and targeted infection for gene delivery. PMID:23104232

  14. Suppression of Drug Resistance in Dengue Virus

    PubMed Central

    Mateo, Roberto; Nagamine, Claude M.

    2015-01-01

    ABSTRACT Dengue virus is a major human pathogen responsible for 400 million infections yearly. As with other RNA viruses, daunting challenges to antiviral design exist due to the high error rates of RNA-dependent RNA synthesis. Indeed, treatment of dengue virus infection with a nucleoside analog resulted in the expected genetic selection of resistant viruses in tissue culture and in mice. However, when the function of the oligomeric core protein was inhibited, no detectable selection of drug resistance in tissue culture or in mice was detected, despite the presence of drug-resistant variants in the population. Suppressed selection of drug-resistant virus correlated with cooligomerization of the targeted drug-susceptible and drug-resistant core proteins. The concept of “dominant drug targets,” in which inhibition of oligomeric viral assemblages leads to the formation of drug-susceptible chimeras, can therefore be used to prevent the outgrowth of drug resistance during dengue virus infection. PMID:26670386

  15. Human Immunodeficiency Virus and Related Retroviruses

    PubMed Central

    Nájera, Rafael; Herrera, M. I.; Andrés, R. de

    1987-01-01

    This paper summarizes the current knowledge on the human immunodeficiency virus (HIV) and related retroviruses, describing basic characteristics of this new group of viruses such as morphologic and genetic structure, biological and cultural properties, virus growth characteristics, genetic variability and virus replication. The discovery of new human and simian retroviruses has prompted the World Health Organization (WHO) to convene a group of experts to establish criteria for their characterization. This will allow rapid identification of new variants that may arise and allow public health measures to be implemented accordingly. Different approaches are made to nomenclature in view of the evolution of knowledge about these viruses, and a system of nomenclature has been proposed by the WHO working group. This system, inspired by the one developed for the influenza viruses, is practical and descriptive, providing information on the origins of the organism and its type. Images PMID:2829446

  16. Impacts of West Nile Virus on wildlife

    USGS Publications Warehouse

    Saito, E.K.; Wild, M.A.

    2004-01-01

    The recent epidemic of West Nile virus in the United States proved to be unexpectedly active and was the largest epidemic of the virus ever recorded. Much remains to be discovered about the ecology and epidemiology of West Nile virus in the United States, including which species are important in maintaining the virus in nature, why some species are more susceptible to lethal infection, and what environmental factors are important in predicting future epidemics. These factors will likely vary regionally, depending on local ecological characteristics. Until scientists better understand the virus and factors influencing its activity, predicting its effects for future seasons is impossible. However, experts are certain about one thing: West Nile virus is here to stay.

  17. Neutralization enzyme immunoassay for influenza virus.

    PubMed Central

    Benne, C A; Harmsen, M; De Jong, J C; Kraaijeveld, C A

    1994-01-01

    A neutralization enzyme immunoassay (N-EIA) was developed for the detection of antibody titer rises in sera of patients infected with influenza A (H3N2) virus. In this N-EIA, a selected strain of influenza A (H3N2) virus was added to monolayers of LLC-MK2 cells in microtiter plates. After 24 h, the replicated virus could be demonstrated with a virus-specific enzyme-labeled monoclonal antibody. Preincubation of the influenza virus with convalescent-phase sera of patients infected with influenza A (H3N2) virus resulted 1 day later in decreased absorbance values that could be used for calculation of neutralization titers. From use of paired serum samples from 10 patients with a history of flu-like symptoms, the results obtained with N-EIA correlated well (r = 0.83) with those of the standard hemagglutination inhibition test. PMID:8027355

  18. Cowpox Virus in Llama, Italy

    PubMed Central

    Brozzi, Alberto; Eleni, Claudia; Polici, Nicola; D’Alterio, Gianlorenzo; Carletti, Fabrizio; Scicluna, Maria Teresa; Castilletti, Concetta; Capobianchi, Maria R.; Di Caro, Antonino; Autorino, Gian Luca; Amaddeo, Demetrio

    2011-01-01

    Cowpox virus (CPXV) was isolated from skin lesions of a llama on a farm in Italy. Transmission electron microscopy showed brick-shaped particles consistent with orthopoxviruses. CPXV-antibodies were detected in llama and human serum samples; a CPXV isolate had a hemagglutinin sequence identical to CPXV-MonKre08/1–2-3 strains isolated from banded mongooses in Germany. PMID:21801638

  19. Avian influenza virus in pregnancy.

    PubMed

    Liu, Shelan; Sha, Jianping; Yu, Zhao; Hu, Yan; Chan, Ta-Chien; Wang, Xiaoxiao; Pan, Hao; Cheng, Wei; Mao, Shenghua; Zhang, Run Ju; Chen, Enfu

    2016-07-01

    The unprecedented epizootic of avian influenza viruses, such as H5N1, H5N6, H7N1 and H10N8, has continued to cause disease in humans in recent years. In 2013, another novel influenza A (H7N9) virus emerged in China, and 30% of those patients died. Pregnant women are particularly susceptible to avian influenza and are more likely to develop severe complications and to die, especially when infection occurs in the middle and late trimesters. Viremia is believed to occur infrequently, and thus vertical transmission induced by avian influenza appears to be rare. However, avian influenza increases the risk of adverse pregnancy outcomes, including spontaneous abortion, preterm birth and fatal distress. This review summarises 39 cases of pregnant women and their fetuses from different countries dating back to 1997, including 11, 15 and 13 infections with H7N9, H5N1 and the 2009 pandemic influenza (H1N1), respectively. We analysed the epidemic features, following the geographical, population and pregnancy trimester distributions; underlying diseases; exposure history; medical timelines; human-to-human transmission; pathogenicity and vertical transmission; antivirus treatments; maternal severity and mortality and pregnancy outcome. The common experiences reported in different countries and areas suggest that early identification and treatment are imperative. In the future, vigilant virologic and epidemiologic surveillance systems should be developed to monitor avian influenza viruses during pregnancy. Furthermore, extensive study on the immune mechanisms should be conducted, as this will guide safe, rational immunomodulatory treatment among this high-risk population. Most importantly, we should develop a universal avian influenza virus vaccine to prevent outbreaks of the different subtypes. Copyright © 2016 John Wiley & Sons, Ltd. PMID:27187752

  20. Endocytosis of Viruses and Bacteria

    PubMed Central

    Cossart, Pascale; Helenius, Ari

    2014-01-01

    Of the many pathogens that infect humans and animals, a large number use cells of the host organism as protected sites for replication. To reach the relevant intracellular compartments, they take advantage of the endocytosis machinery and exploit the network of endocytic organelles for penetration into the cytosol or as sites of replication. In this review, we discuss the endocytic entry processes used by viruses and bacteria and compare the strategies used by these dissimilar classes of pathogens. PMID:25085912

  1. Probiotics in respiratory virus infections.

    PubMed

    Lehtoranta, L; Pitkäranta, A; Korpela, R

    2014-08-01

    Viral respiratory infections are the most common diseases in humans. A large range of etiologic agents challenge the development of efficient therapies. Research suggests that probiotics are able to decrease the risk or duration of respiratory infection symptoms. However, the antiviral mechanisms of probiotics are unclear. The purpose of this paper is to review the current knowledge on the effects of probiotics on respiratory virus infections and to provide insights on the possible antiviral mechanisms of probiotics. A PubMed and Scopus database search was performed up to January 2014 using appropriate search terms on probiotic and respiratory virus infections in cell models, in animal models, and in humans, and reviewed for their relevance. Altogether, thirty-three clinical trials were reviewed. The studies varied highly in study design, outcome measures, probiotics, dose, and matrices used. Twenty-eight trials reported that probiotics had beneficial effects in the outcome of respiratory tract infections (RTIs) and five showed no clear benefit. Only eight studies reported investigating viral etiology from the respiratory tract, and one of these reported a significant decrease in viral load. Based on experimental studies, probiotics may exert antiviral effects directly in probiotic-virus interaction or via stimulation of the immune system. Although probiotics seem to be beneficial in respiratory illnesses, the role of probiotics on specific viruses has not been investigated sufficiently. Due to the lack of confirmatory studies and varied data available, more randomized, double-blind, and placebo-controlled trials in different age populations investigating probiotic dose response, comparing probiotic strains/genera, and elucidating the antiviral effect mechanisms are necessary. PMID:24638909

  2. Monitoring Intact Viruses Using Aptamers.

    PubMed

    Kumar, Penmetcha K R

    2016-01-01

    Viral diagnosis and surveillance are necessary steps in containing the spread of viral diseases, and they help in the deployment of appropriate therapeutic interventions. In the past, the commonly employed viral detection methods were either cell-culture or molecule-level assays. Most of these assays are laborious and expensive, require special facilities, and provide a slow diagnosis. To circumvent these limitations, biosensor-based approaches are becoming attractive, especially after the successful commercialization of glucose and other biosensors. In the present article, I have reviewed the current progress using the biosensor approach for detecting intact viruses. At the time of writing this review, three types of bioreceptor surfaces (antibody-, glycan-, and aptamer-based) have been explored on different sensing platforms for detecting intact viruses. Among these bioreceptors, aptamer-based sensors have been increasingly explored for detecting intact viruses using surface plasmon resonance (SPR) and other platforms. Special emphasis is placed on the aptamer-based SPR platform in the present review. PMID:27527230

  3. Viruses causing diarrhoea in AIDS.

    PubMed

    Pollok, R C

    2001-01-01

    Opportunistic viral enteritis is an important gastrointestinal manifestation of HIV related disease. Cytomegalovirus (CMV) is a well established aetiological agent of disease in the gastrointestinal tract in this group. CMV enteritis may affect any region of the bowel, most commonly the colon. Diagnosis and management of these infections may be difficult. The role of other viruses in so-called 'pathogen-negative' diarrhoea remains controversial. The clinical importance of HIV-specific enteropathy is probably limited. Several viruses including astrovirus, picobirnavirus, small round structured virus and rotavirus have been implicated HIV-related diarrhoea. In addition, adenovirus has been linked to persistent diarrhoea in patients with a characteristic adenovirus colitis. The spectrum of disease morbidity and mortality amongst HIV patients has altered dramatically since the wide spread use of highly active antiretroviral therapy (HAART). Opportunistic infections, including CMV infection of the gastrointestinal tract in patients with AIDS, have diminished greatly. AIDS patients with CMV are able successfully to discontinue anti-CMV treatment without disease reactivation and with a parallel reduction in CMV viraemia following the initiation of HAART. PMID:11444032

  4. Virus Removal by Biogenic Cerium

    SciTech Connect

    De Gusseme, B.; Du Laing, G; Hennebel, T; Renard, P; Chidambaram, D; Fitts, J; Bruneel, E; Van Driessche, I; Verbeken, K; et. al.

    2010-01-01

    The rare earth element cerium has been known to exert antifungal and antibacterial properties in the oxidation states +III and +IV. This study reports on an innovative strategy for virus removal in drinking water by the combination of Ce(III) on a bacterial carrier matrix. The biogenic cerium (bio-Ce) was produced by addition of aqueous Ce(III) to actively growing cultures of either freshwater manganese-oxidizing bacteria (MOB) Leptothrix discophora or Pseudomonas putida MnB29. X-ray absorption spectroscopy results indicated that Ce remained in its trivalent state on the bacterial surface. The spectra were consistent with Ce(III) ions associated with the phosphoryl groups of the bacterial cell wall. In disinfection assays using a bacteriophage as model, it was demonstrated that bio-Ce exhibited antiviral properties. A 4.4 log decrease of the phage was observed after 2 h of contact with 50 mg L{sup -1} bio-Ce. Given the fact that virus removal with 50 mg L{sup -1} Ce(III) as CeNO{sub 3} was lower, the presence of the bacterial carrier matrix in bio-Ce significantly enhanced virus removal.

  5. Virus removal by biogenic cerium.

    PubMed

    De Gusseme, Bart; Du Laing, Gijs; Hennebel, Tom; Renard, Piet; Chidambaram, Dev; Fitts, Jeffrey P; Bruneel, Els; Van Driessche, Isabel; Verbeken, Kim; Boon, Nico; Verstraete, Willy

    2010-08-15

    The rare earth element cerium has been known to exert antifungal and antibacterial properties in the oxidation states +III and +IV. This study reports on an innovative strategy for virus removal in drinking water by the combination of Ce(III) on a bacterial carrier matrix. The biogenic cerium (bio-Ce) was produced by addition of aqueous Ce(III) to actively growing cultures of either freshwater manganese-oxidizing bacteria (MOB) Leptothrix discophora or Pseudomonas putida MnB29. X-ray absorption spectroscopy results indicated that Ce remained in its trivalent state on the bacterial surface. The spectra were consistent with Ce(III) ions associated with the phosphoryl groups of the bacterial cell wall. In disinfection assays using a bacteriophage as model, it was demonstrated that bio-Ce exhibited antiviral properties. A 4.4 log decrease of the phage was observed after 2 h of contact with 50 mg L(-1) bio-Ce. Given the fact that virus removal with 50 mg L(-1) Ce(III) as CeNO(3) was lower, the presence of the bacterial carrier matrix in bio-Ce significantly enhanced virus removal. PMID:20704235

  6. Satellite Tobacco Mosaic Virus Structure

    NASA Technical Reports Server (NTRS)

    2000-01-01

    The structure of the Satellite Tobacco Mosaic Viurus (STMV)--one of the smallest viruses known--has been successfully reduced using STMV crystals grown aboard the Space Shuttle in 1992 and 1994. The STMV crystals were up to 30 times the volume of any seen in the laboratory. At the time they gave the best resolution data ever obtained on any virus crystal. STMV is a small icosahedral plant virus, consisting of a protein shell made up of 60 identical protein subunits of molecular weight 17,500. Particularly noteworthy is the fact that, in contrast to the crystals grown on Earth, the crystals grown under microgravity conditions were visually perfect, with no striations or clumping of crystals. Furthermore, the x-ray diffraction data obtained from the space-grown crystals was of a much higher quality than the best data available at that time from ground-based crystals. This stylized ribbon model shows the protein coat in white and the nucleic acid in yellow. STMV is used because it is a simple protein to work with; studies are unrelated to tobacco. Credit: Dr. Alex McPherson, University of California at Irvin.

  7. Immunosuppression During Influenza Virus Infection

    PubMed Central

    Kantzler, G. B.; Lauteria, S. F.; Cusumano, C. L.; Lee, J. D.; Ganguly, R.; Waldman, R. H.

    1974-01-01

    The effects of a live attenuated influenza vaccine and subsequent challenge with virulent influenza virus on the delayed hypersensitivity skin test, and the in vitro response of lymphocytes were evaluated. Volunteers were skin tested before and after administration of vaccine or placebo and challenge with PPD (a purified protein derivative of Mycobacterium tuberculosis), candida, mumps, and trichophytin, and their lymphocytes were tested for [3H]thymidine uptake in response to phytohemagglutin. Of eight volunteers who showed evidence of viral replication after administration of the attenuated vaccine, four had a significant diminution in their skin test response, whereas 8 of 13 volunteers infected with virulent influenza virus showed a diminution. Of the 21 volunteers who were infected with either attenuated or virulent influenza virus, 12 showed suppression of their phytohemagglutin response. None of the volunteers who were given placebo vaccine, or who showed no evidence for viral replication after immunization or challenge, had a suppression of their skin test or phytohemagglutin responses. Although most of the infected volunteers demonstrated suppression of their T-cell function, there was no evidence of a similar suppression of B-cell function. PMID:16558116

  8. Infectious laryngotracheitis virus in chickens.

    PubMed

    Ou, Shan-Chia; Giambrone, Joseph J

    2012-10-12

    Infectious laryngotracheitis (ILT) is an important respiratory disease of chickens and annually causes significant economic losses in the poultry industry world-wide. ILT virus (ILTV) belongs to alphaherpesvirinae and the Gallid herpesvirus 1 species. The transmission of ILTV is via respiratory and ocular routes. Clinical and post-mortem signs of ILT can be separated into two forms according to its virulence. The characteristic of the severe form is bloody mucus in the trachea with high mortality. The mild form causes nasal discharge, conjunctivitis, and reduced weight gain and egg production. Conventional polymerase chain reaction (PCR), nested PCR, real-time PCR, and loop-mediated isothermal amplification were developed to detect ILTV samples from natural or experimentally infected birds. The PCR combined with restriction fragment length polymorphism (RFLP) can separate ILTVs into several genetic groups. These groups can separate vaccine from wild type field viruses. Vaccination is a common method to prevent ILT. However, field isolates and vaccine viruses can establish latent infected carriers. According to PCR-RFLP results, virulent field ILTVs can be derived from modified-live vaccines. Therefore, modified-live vaccine reversion provides a source for ILT outbreaks on chicken farms. Two recently licensed commercial recombinant ILT vaccines are also in use. Other recombinant and gene-deficient vaccine candidates are in the developmental stages. They offer additional hope for the control of this disease. However, in ILT endemic regions, improved biosecurity and management practices are critical for improved ILT control. PMID:24175219

  9. Infectious laryngotracheitis virus in chickens

    PubMed Central

    Ou, Shan-Chia; Giambrone, Joseph J

    2012-01-01

    Infectious laryngotracheitis (ILT) is an important respiratory disease of chickens and annually causes significant economic losses in the poultry industry world-wide. ILT virus (ILTV) belongs to alphaherpesvirinae and the Gallid herpesvirus 1 species. The transmission of ILTV is via respiratory and ocular routes. Clinical and post-mortem signs of ILT can be separated into two forms according to its virulence. The characteristic of the severe form is bloody mucus in the trachea with high mortality. The mild form causes nasal discharge, conjunctivitis, and reduced weight gain and egg production. Conventional polymerase chain reaction (PCR), nested PCR, real-time PCR, and loop-mediated isothermal amplification were developed to detect ILTV samples from natural or experimentally infected birds. The PCR combined with restriction fragment length polymorphism (RFLP) can separate ILTVs into several genetic groups. These groups can separate vaccine from wild type field viruses. Vaccination is a common method to prevent ILT. However, field isolates and vaccine viruses can establish latent infected carriers. According to PCR-RFLP results, virulent field ILTVs can be derived from modified-live vaccines. Therefore, modified-live vaccine reversion provides a source for ILT outbreaks on chicken farms. Two recently licensed commercial recombinant ILT vaccines are also in use. Other recombinant and gene-deficient vaccine candidates are in the developmental stages. They offer additional hope for the control of this disease. However, in ILT endemic regions, improved biosecurity and management practices are critical for improved ILT control. PMID:24175219

  10. Zika Virus: the Latest Newcomer

    PubMed Central

    Saiz, Juan-Carlos; Vázquez-Calvo, Ángela; Blázquez, Ana B.; Merino-Ramos, Teresa; Escribano-Romero, Estela; Martín-Acebes, Miguel A.

    2016-01-01

    Since the beginning of this century, humanity has been facing a new emerging, or re-emerging, virus threat almost every year: West Nile, Influenza A, avian flu, dengue, Chikungunya, SARS, MERS, Ebola, and now Zika, the latest newcomer. Zika virus (ZIKV), a flavivirus transmitted by Aedes mosquitoes, was identified in 1947 in a sentinel monkey in Uganda, and later on in humans in Nigeria. The virus was mainly confined to the African continent until it was detected in south-east Asia the 1980’s, then in the Micronesia in 2007 and, more recently in the Americas in 2014, where it has displayed an explosive spread, as advised by the World Health Organization, which resulted in the infection of hundreds of thousands of people. ZIKV infection was characterized by causing a mild disease presented with fever, headache, rash, arthralgia, and conjunctivitis, with exceptional reports of an association with Guillain–Barre syndrome (GBS) and microcephaly. However, since the end of 2015, an increase in the number of GBS associated cases and an astonishing number of microcephaly in fetus and new-borns in Brazil have been related to ZIKV infection, raising serious worldwide public health concerns. Clarifying such worrisome relationships is, thus, a current unavoidable goal. Here, we extensively review what is currently known about ZIKV, from molecular biology, transmission routes, ecology, and epidemiology, to clinical manifestations, pathogenesis, diagnosis, prophylaxis, and public health. PMID:27148186

  11. Zika Virus: the Latest Newcomer.

    PubMed

    Saiz, Juan-Carlos; Vázquez-Calvo, Ángela; Blázquez, Ana B; Merino-Ramos, Teresa; Escribano-Romero, Estela; Martín-Acebes, Miguel A

    2016-01-01

    Since the beginning of this century, humanity has been facing a new emerging, or re-emerging, virus threat almost every year: West Nile, Influenza A, avian flu, dengue, Chikungunya, SARS, MERS, Ebola, and now Zika, the latest newcomer. Zika virus (ZIKV), a flavivirus transmitted by Aedes mosquitoes, was identified in 1947 in a sentinel monkey in Uganda, and later on in humans in Nigeria. The virus was mainly confined to the African continent until it was detected in south-east Asia the 1980's, then in the Micronesia in 2007 and, more recently in the Americas in 2014, where it has displayed an explosive spread, as advised by the World Health Organization, which resulted in the infection of hundreds of thousands of people. ZIKV infection was characterized by causing a mild disease presented with fever, headache, rash, arthralgia, and conjunctivitis, with exceptional reports of an association with Guillain-Barre syndrome (GBS) and microcephaly. However, since the end of 2015, an increase in the number of GBS associated cases and an astonishing number of microcephaly in fetus and new-borns in Brazil have been related to ZIKV infection, raising serious worldwide public health concerns. Clarifying such worrisome relationships is, thus, a current unavoidable goal. Here, we extensively review what is currently known about ZIKV, from molecular biology, transmission routes, ecology, and epidemiology, to clinical manifestations, pathogenesis, diagnosis, prophylaxis, and public health. PMID:27148186

  12. Hendra virus ecology and transmission.

    PubMed

    Field, Hume E

    2016-02-01

    Hendra virus causes acute and highly fatal infection in horses and humans. Pteropid bats (flying-foxes) are the natural host of the virus, with age and species being risk factors for infection. Urine is the primary route of excretion in flying-foxes, with viral RNA more frequently detected in Pteropus alecto and P. conspicillatus than other species. Infection prevalence in flying-foxes can vary between and within years, with a winter peak of excretion occurring in some regions. Vertical transmission and recrudescing infection has been reported in flying-foxes, but horizontal transmission is evidently the primary mode of transmission. The most parsimonious mode of flying-fox to horse transmission is equine contact (oro-nasal, conjunctival) with infected flying-fox urine, either directly, or via urine-contaminated pasture or surfaces. Horse to horse transmission is inefficient, requiring direct contact with infected body fluids. Flying-fox to human transmission has not been recorded; all human cases have been associated with close and direct contact with infected horses. Canine cases (subclinical) have also been limited to equine case properties. Notwithstanding the recent availability of an effective vaccine for horses, a comprehensive understanding of Hendra virus ecology and transmission is essential to limit inter-species transmission. PMID:26978066

  13. West Nile Virus and wildlife

    USGS Publications Warehouse

    Marra, P.P.; Griffing, S.; Caffrey, C.; Kilpatrick, A.M.; McLean, R.; Brand, C.; Saito, E.; Dupuis, A.P.; Kramer, L.; Novak, R.

    2004-01-01

    West Nile virus (WNV) has spread rapidly across North America, resulting in human deaths and in the deaths of untold numbers of birds, mammals, and reptiles. The virus has reached Central America and the Caribbean and may spread to Hawaii and South America. Although tens of thousands of birds have died, and studies of some bird species show local declines, few regionwide declines can be attributed to WNV. Predicting future impacts of WNV on wildlife, and pinpointing what drives epidemics, will require substantial additional research into host susceptibility, reservoir competency, and linkages between climate, mosquitoes, and disease. Such work will entail a collaborative effort between scientists in governmental research groups, in surveillance and control programs, and in nongovernmental organizations. West Nile virus was not the first, and it will not be the last, exotic disease to be introduced to the New World. Its spread in North America highlights the need to strengthen animal monitoring programs and to integrate them with research on disease ecology.

  14. RNA Virus Reverse Genetics and Vaccine Design

    PubMed Central

    Stobart, Christopher C.; Moore, Martin L.

    2014-01-01

    RNA viruses are capable of rapid spread and severe or potentially lethal disease in both animals and humans. The development of reverse genetics systems for manipulation and study of RNA virus genomes has provided platforms for designing and optimizing viral mutants for vaccine development. Here, we review the impact of RNA virus reverse genetics systems on past and current efforts to design effective and safe viral therapeutics and vaccines. PMID:24967693

  15. Influenza virus neuraminidase: structure, antibodies, and inhibitors.

    PubMed Central

    Colman, P. M.

    1994-01-01

    The determination of the 3-dimensional structure of the influenza virus neuraminidase in 1983 has served as a platform for understanding interactions between antibodies and protein antigens, for investigating antigenic variation in influenza viruses, and for devising new inhibitors of the enzyme. That work is reviewed here, together with more recent developments that have resulted in one of the inhibitors entering clinical trials as an anti-influenza virus drug. PMID:7849585

  16. Modeling Transport of Viruses in Fractured Rock

    NASA Astrophysics Data System (ADS)

    Sleep, B. E.; Mondal, P. K.

    2011-12-01

    Fractured rock aquifers are frequently used for water supply for human consumption. In many instances the fractured rock aquifers are vulnerable to contamination by pathogens, including viruses, due to co-location of on-site septic systems, wastewater discharges, biosolids and agricultural activities. Approximately half of the illnesses associated with groundwater consumption in the Unites States have been attributed to viral contamination. A number of these cases have been related to transport of viruses from septic systems to drinking water wells. Despite the potential for rapid transport of viruses through rock fractures to drinking water wells, the understanding of virus transport in fractured rock is limited. In particular, the impacts of virus size, fracture aperture variability and roughness, matrix porosity, groundwater velocity, and geochemical conditions have not been well studied. In this study, a multidimensional model for virus transport in variable aperture fractures is presented. The model is applied to laboratory experiments on transport of virus-sized latex microspheres (0.02 and 0.2 microns) and bacteriophages (MS2 and PR772) in artificially fractured dolomite rocks. In these experiments significant impacts of particle size, fracture characteristics, groundwater velocity, and geochemistry were observed. Given the variability in aperture distribution and associated spatial variation in groundwater flow field, one-dimensional models were not suitable for a comprehensive evaluation of the mechanisms governing the microsphere and bacteriophage transport. Various relationships for virus retention (attachment and detachment) are evaluated to provide insight into the governing processes in virus transport in fractured rock. In addition, the role of virus size, fracture aperture variability, fracture roughness, fracture surface charge, matrix porosity, groundwater velocity, and ionic strength in virus transport are evaluated. Scale-up to the field is

  17. Influenza Virus Propagation in Embryonated Chicken Eggs

    PubMed Central

    Brauer, Rena; Chen, Peter

    2015-01-01

    Influenza infection is associated with about 36,000 deaths and more than 200,000 hospitalizations every year in the United States. The continuous emergence of new influenza virus strains due to mutation and re-assortment complicates the control of the virus and necessitates the permanent development of novel drugs and vaccines. The laboratory-based study of influenza requires a reliable and cost-effective method for the propagation of the virus. Here, a comprehensive protocol is provided for influenza A virus propagation in fertile chicken eggs, which consistently yields high titer viral stocks. In brief, serum pathogen-free (SPF) fertilized chicken eggs are incubated at 37 °C and 55-60% humidity for 10 – 11 days. Over this period, embryo development can be easily monitored using an egg candler. Virus inoculation is carried out by injection of virus stock into the allantoic cavity using a needle. After 2 days of incubation at 37 °C, the eggs are chilled for at least 4 hr at 4 °C. The eggshell above the air sac and the chorioallantoic membrane are then carefully opened, and the allantoic fluid containing the virus is harvested. The fluid is cleared from debris by centrifugation, aliquoted and transferred to -80 °C for long-term storage. The large amount (5-10 ml of virus-containing fluid per egg) and high virus titer which is usually achieved with this protocol has made the usage of eggs for virus preparation our favorable method, in particular for in vitro studies which require large quantities of virus in which high dosages of the same virus stock are needed. PMID:25867050

  18. Hepatitis C Virus Exploitation of Processing Bodies.

    PubMed

    Biegel, Jason M; Pager, Cara T

    2016-05-15

    During infection, positive-strand RNA viruses subvert cellular machinery involved in RNA metabolism to translate viral proteins and replicate viral genomes to avoid or disable the host defense mechanisms. Cytoplasmic RNA granules modulate the stabilities of cellular and viral RNAs. Understanding how hepatitis C virus and other flaviviruses interact with the host machinery required for protein synthesis, localization, and degradation of mRNAs is important for elucidating how these processes occur in both virus-infected and uninfected cells. PMID:26937026

  19. Influenza virus propagation in embryonated chicken eggs.

    PubMed

    Brauer, Rena; Chen, Peter

    2015-01-01

    Influenza infection is associated with about 36,000 deaths and more than 200,000 hospitalizations every year in the United States. The continuous emergence of new influenza virus strains due to mutation and re-assortment complicates the control of the virus and necessitates the permanent development of novel drugs and vaccines. The laboratory-based study of influenza requires a reliable and cost-effective method for the propagation of the virus. Here, a comprehensive protocol is provided for influenza A virus propagation in fertile chicken eggs, which consistently yields high titer viral stocks. In brief, serum pathogen-free (SPF) fertilized chicken eggs are incubated at 37 °C and 55-60% humidity for 10-11 days. Over this period, embryo development can be easily monitored using an egg candler. Virus inoculation is carried out by injection of virus stock into the allantoic cavity using a needle. After 2 days of incubation at 37 °C, the eggs are chilled for at least 4 hr at 4 °C. The eggshell above the air sac and the chorioallantoic membrane are then carefully opened, and the allantoic fluid containing the virus is harvested. The fluid is cleared from debris by centrifugation, aliquoted and transferred to -80 °C for long-term storage. The large amount (5-10 ml of virus-containing fluid per egg) and high virus titer which is usually achieved with this protocol has made the usage of eggs for virus preparation our favorable method, in particular for in vitro studies which require large quantities of virus in which high dosages of the same virus stock are needed. PMID:25867050

  20. Virus-induced gene complementation in tomato

    PubMed Central

    Kong, Jinhua; Chen, Weiwei; Shen, Jiajia; Qin, Cheng; Lai, Tongfei; Zhang, Pengcheng; Wang, Ying; Wu, Chaoqun; Yang, Xin; Hong, Yiguo

    2013-01-01

    Virus-induced gene complementation (VIGC), a plant virus technology based on Potato virus X for transient overexpression of endogenous genes complemented tomato mutants, resulting in non-ripening fruits to ripen. This efficient “gain-of-function” approach involves no stable transformation, and reveals a fruit-specific transcriptional network that may exist among key transcription factors in modulating tomato ripening. Thus, VIGC represents a novel and feasible strategy for gene functional analysis in plants. PMID:24305652