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1

VARIACIÓN FENOTÍPICA DE ALGUNOS AISLAMIENTOS MEXICANOS DEL VIRUS DE LA MARCHITEZ MANCHADA DEL TOMATE (TSWV) PHENOTYPIC VARIATION OF SOME MEXICAN ISOLATES OF TOMATO SPOTTED WILT VIRUS (TSWV)  

Microsoft Academic Search

Tomato spotted wilt virus (TSWV.Tospovirus) was detected in tomatillo (Physalis ixocarpa) plants, with symptoms of leaf spots, wilting, and generalized necrosis, grown in the states of México, Puebla and Morelos. Symptoms' expression in susceptible hosts indicated the possible presence of strains of this virus. The isolates of TSWV were identified as belonging to the group of localized lesion pathogens (TSWV-PL),

Rodolfo De La Torre-Almaráz; Hobbs A. Houston; Rodrigo Valverde

2

Polimorfismos genéticos de aislamientos del género Malassezia obtenidos en Colombia de pacientes con lesión dermatológica y sin ella  

Microsoft Academic Search

Introducción. Las especies del género Malassezia se consideran levaduras oportunistas emergentes de gran importancia. Han sido asociadas a diferentes patologías dermatológicas y sistémicas de las cuales se aislan una o más especies de este género. El papel de estas levaduras en las enfermedades dermatológicas no se ha aclarado completamente, ya que la Malassezia spp. pertenece a la flora normal de

Adriana M. Celis; Maria Caridad Cepero de García

3

Cache Valley Virus in the Del Mar VA Peninsula. Ii. Identity of Virus Recovered from Mosquitoes.  

National Technical Information Service (NTIS)

Viruses recovered on the Del Mar Va peninsula from northern salt-marsh mosquitoes Aedes sollicitans and Aedes taeniorhynchus from 1961 through 1964 were shown to be similar to, if not indistinguishable from, Cache Valley virus, and different from Tensaw v...

T. M. Yuill E. L. Buescher

1969-01-01

4

Molecular survey of hepatitis C virus in the touristic city of Mar del Plata, Argentina.  

PubMed

The global epidemiology of hepatitis C virus (HCV) may be roughly described by two groups of genotypes: the worldwide distributed ones (subtypes 1a, 1b, 2a and 3a, among others) and the endemic ones (subtypes 4a, 5a, 6a, among others). Epidemiological and population dynamic studies of the worldwide distributed genotypes have shown that subtypes 1a and 3a are common among intravenous drug users (IDUs) and that they are also in expansion in some countries. The molecular survey of HCV provides some clues about the epidemiological status of the infections in a local scale and the phylogenetic and demographic reconstruction analyses complement this study by inferring whether the infections of certain subtypes are in a steady state or expanding. Here, a molecular survey of the HCV variants that circulate in the touristic city of Mar del Plata (Buenos Aires, Argentina) was performed in samples obtained from 42 patients. The subtypes detected were 1a (32 patients), 3a (8 patients) and 1b (2 patients). The demographic history of subtype 1a inferred using the sequence data showed an exponential growth in the 1990's. The period of viral expansion was delayed compared with that observed for the same genotype in other countries where the transmission was associated with IDUs. Also, the phylogeographic analysis of HCV-1a showed a statistically significant association between the location of the samples and the phylogeny, which may be the result of the local transmission of HCV in the city. The molecular analysis helped in the description of the complex epidemiological context of a touristic city, and pointed out that some sanitary measures should be taken in order to reduce the transmission of HCV (and maybe of HIV) among IDUs. PMID:23028605

Culasso, Andrés C A; Elizalde, Mercedes; Campos, Rodolfo H; Barbini, Luciana

2012-09-24

5

La retirada de una campaña publicitaria para promoción de la vacuna tetravalente del virus del papiloma humano en España  

Microsoft Academic Search

The inclusion of the quadrivalent human papilloma virus (HPV) vaccine in the schedule of the Spanish National Health System sparked the debate over Gardasil®, which was presented to the public as a “vaccine against cervical cancer”. In this context, Sanofi Pasteur MSD was sued for misleading advertising in the campaign “cuentaselo.org”. Although the complaint was not admitted, the lawsuit triggered

Marta Martín-Llaguno; Carlos Álvarez-Dardet

2010-01-01

6

Cache Valley Virus in the Del Mar VA Peninsula. I. Virologic and Serologic Evidence of Infection.  

National Technical Information Service (NTIS)

An arthropod-borne virus, shown to be a member of the Bunyamwera group and closely related to Cache Valley virus, was recovered 12 times from slat-marsh mosquitoes collected from off-shore Virginia Islands between 1961 and 1964. Mosquito infection was det...

E. L. Buescher R. J. Byrne G. C. Clarke D. J. Gould P. K. Russell

1969-01-01

7

Cache Valley Virus in the Del Mar VA Peninsula. Iv. Biological Transmission of the Virus by AEDES Sollicitans and AEDES Taeniorhynchus.  

National Technical Information Service (NTIS)

Laboratory-reared Aedes taeniorhynchus and Aedes sollicitans were readily infected with Cache Valley virus after ingestion of artificial mixtures of virus and defibrinated rabbit blood. Whereas some mosquitoes were infected with as little as three infecti...

T. M. Yuill P. H. Thompson

1969-01-01

8

Aislamiento de keratinomyces ajelloi y microsporum gypseum del suelo de la ciudad de buenos aires  

Microsoft Academic Search

Summary Keratinomyces ajelloi andMicrosporum gypseum have been isolated from soil samples from public gardens and from a breeding-place with rabbits and fowls in the urban zone of the Buenos Aires city, usingVanbreuseghem's technique with hair bait.

Edith Varsavsky

1962-01-01

9

Virus Resistance  

Technology Transfer Automated Retrieval System (TEKTRAN)

Identification, characterization and deployment of virus resistant maize are complex tasks requiring multidisciplinary approaches. Insect transmission of viruses in nature and the potential presence of biologically distinct virus strains complicate screening for virus resistance. At least ten maize...

10

Influencia de virus respiratorios, frío y contaminación aérea en la infección respiratoria aguda baja del lactante Influence of respiratory viruses, cold weather and air pollution in the incidence of lower respiratory tract infections in infants children  

Microsoft Academic Search

Background: All winters, there is an increase in the number of pediatric consultations, associated to three factors: cold weather, air pollution and respiratory virus epidemics. Aim: To study the influence of these three factors in the demand for pediatric consultations between March and September, in an area of Metropolitan Santiago. Patients and Methods: The number of consultations between March and

Luis F Avendaño; Alejandra Céspedes L; Ximena Stecher G; María Angélica

11

Atlas del Genoma del Cáncer  

Cancer.gov

El Atlas del Genoma del Cáncer es una iniciativa de los Institutos Nacionales de la Salud (NIH) para crear mapas multidimensionales completos de los cambios genómicos clave en los tipos y subtipos principales de cáncer.

12

Hepadna viruses  

SciTech Connect

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.

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

1987-01-01

13

Camelpox virus  

Microsoft Academic Search

Camelpox virus (CMLV) causes a smallpox-like illness in a unique host, the camel. The disease is enzootic in almost all regions where camel husbandry is practiced, and is responsible for severe economic losses. Although it is genetically the closest known virus to variola virus, the etiologic agent of smallpox, CMLV remains poorly studied. It is characterized by a narrow host

Sophie Duraffour; Hermann Meyer; Graciela Andrei; Robert Snoeck

2011-01-01

14

Identification of duck plague virus by polymerase chain reaction  

USGS Publications Warehouse

A polymerase chain reaction (PCR) assay was developed for detecting duck plague virus. A 765-bp EcoRI fragment cloned from the genome of the duck plague vaccine (DP-VAC) virus was sequenced for PCR primer development. The fragment sequence was found by GenBank alignment searches to be similar to the 3a?? ends of an undefined open reading frame and the gene for DNA polymerase protein in other herpesviruses. Three of four primer sets were found to be specific for the DP-VAC virus and 100% (7/7) of field isolates but did not amplify DNA from inclusion body disease of cranes virus. The specificity of one primer set was tested with genome templates from other avian herpesviruses, including those from a golden eagle, bald eagle, great horned owl, snowy owl, peregrine falcon, prairie falcon, pigeon, psittacine, and chicken (infectious laryngotracheitis), but amplicons were not produced. Hence, this PCR test is highly specific for duck plague virus DNA. Two primer sets were able to detect 1 fg of DNA from the duck plague vaccine strain, equivalent to five genome copies. In addition, the ratio of tissue culture infectious doses to genome copies of duck plague vaccine virus from infected duck embryo cells was determined to be 1:100, making the PCR assay 20 times more sensitive than tissue culture for detecting duck plague virus. The speed, sensitivity, and specificity of this PCR provide a greatly improved diagnostic and research tool for studying the epizootiology of duck plague. /// Se desarroll?? una prueba de reacci??n en cadena por la polimerasa para detectar el virus de la peste del pato. Un fragmento EcoRI de 765 pares de bases clonado del genoma del virus vacunal de la peste del pato fue secuenciado para la obtenci??n de los iniciadores de la prueba de la reacci??n en cadena por la polimerasa. En investigaciones de alineaci??n en el banco de genes ('GenBank') se encontr?? que la secuencia del fragmento era similar a los extremos 3a?? de un marco de lectura abierto indefinido y al gen para la proteina de la DNA polimerasa en otros virus herpes. Se encontraron tres o cuatro grupos de iniciadores especificos para el virus vacunal y para el 100% (7/7) de los a??slamientos de campo, pero no amplificaron el DNA del virus de hepatitis por cuerpos de inclusi??n de grullas. Se analiz?? la especificidad de un primer juego de iniciadores con moldes del genoma de otros virus herpes aviares, incluyendo el ?!guila dorada, ?!guila de cabeza blanca, lechuza de cuernos grandes, lechuza blanca, halc??n peregrino, palomas, aves psit?!cidas y pollos (virus de laringotraqueitis infecciosa), pero no se produjeron los productos finales. Por lo tanto, esta prueba de reacci??n en cadena por la polimerasa es altamente especifica para el DNA del virus. Dos grupos de iniciadores fueron capaces de detectar un fragmento de DNA de la cepa vacunal equivalente a cinco copias del genoma. Adem?!s, se determin?? que la proporci??n de la dosis infecciosa en cultivo celular y copias del genoma del virus vacunal de c??lulas de embri??n de pato infectadas era de 10 a 100 respectivamente, haciendo la prueba de la reacci??n en cadena por la polimerasa 20 veces m?!s sensible que el cultivo celular para detectar el virus. La velocidad, sensibilidad y especificidad de la prueba de la reacci??n en cadena por la polimerasa suministra una herramienta de investigaci??n y de diagn??stico altamente mejorada para el estudio de la epizootiolog?-a del virus.

Hansen, W. R.; Brown, Sean E.; Nashold, S. W.; Knudson, D. L.

1999-01-01

15

Phytophthora viruses.  

PubMed

Phytophthora sp. is a genus in the oomycetes, which are similar to filamentous fungi in morphology and habitat, but phylogenetically more closely related to brown algae and diatoms and fall in the kingdom Stramenopila. In the past few years, several viruses have been characterized in Phytophthora species, including four viruses from Phytophthora infestans, the late blight pathogen, and an endornavirus from an unnamed Phytophthora species from Douglas fir. Studies on Phytophthora viruses have revealed several interesting systems. Phytophthora infestans RNA virus 1 (PiRV-1) and PiRV-2 are likely the first members of two new virus families; studies on PiRV-3 support the establishment of a new virus genus that is not affiliated with established virus families; PiRV-4 is a member of Narnaviridae, most likely in the genus Narnavirus; and Phytophthora endornavirus 1 (PEV1) was the first nonplant endornavirus at the time of reporting. Viral capsids have not been found in any of the above-mentioned viruses. PiRV-1 demonstrated a unique genome organization that requires further examination, and PiRV-2 may have played a role in late blight resurgence in 1980s-1990s. PMID:23498912

Cai, Guohong; Hillman, Bradley I

2013-01-01

16

Diferencias en las características sociales, conductas de riesgo y prevalencia de infección por el virus de la inmunodeficiencia humana e infecciones de transmisión sexual entre trabajadoras del sexo españolas e inmigrantes en Cataluña  

Microsoft Academic Search

Background and objectiveTo describe and compare the social characteristics, human immunodeficiency virus (HIV), Chlamydia trachomatis and Neisseria gonorrhoae prevalences, and risk behaviours among immigrant female sex workers (FSW) according to their geographical area of origin.

Cinta Folch; Cristina Sanclemente; Anna Esteve; Elisa Martró; Sonia Molinos; Jordi Casabona

2009-01-01

17

Ganjam virus.  

PubMed

Ganjam virus (GANV), a member of genus Nairovirus of family Bunyavirdae is of considerable veterinary importance in India. Though, predominantly tick borne, GANV was also isolated from mosquitoes, man and sheep. Neutralizing and complement fixing antibodies to GANV have been detected in animal and human sera collected from different parts of the country. Thirty three strains of GANV have been isolated from India, mainly from Haemaphysalis ticks. The virus replicated in certain vertebrate and mosquito cell lines and found pathogenic to laboratory animals. One natural infection and five laboratory-acquired infections in men were also reported. GANV is antigenically related to Nairobi sheep disease virus (NSDV) of Africa, which is highly pathogenic for sheep and goats causing 70-90 per cent mortality among the susceptible population. Recent molecular studies have demonstrated that GANV is an Asian variant of NSDV and both these viruses are related to the dreaded Crimean Congo haemorrhagic fever (CCHF) group viruses. The versatility of the virus to replicate in different arthropod species, its ability to infect sheep, goat and man makes it an important zoonotic agent. PMID:20090098

Sudeep, A B; Jadi, R S; Mishra, A C

2009-11-01

18

West Nile Virus  

MedlinePLUS

... virus is a virus that can infect humans, birds, horses and mosquitoes. Infection from this virus is ... spread by mosquitoes. Mosquitoes become infected by biting birds that carry the virus. People can get West ...

19

Influenza A Virus Induces an Immediate Cytotoxic Activity in All Major Subsets of Peripheral Blood Mononuclear Cells  

PubMed Central

Background A replication defective influenza A vaccine virus (delNS1 virus) was developed. Its attenuation is due to potent stimulation of the innate immune system by the virus. Since the innate immune system can also target cancer cells, we reasoned that delNS1 virus induced immune-stimulation should also lead to the induction of innate cytotoxic effects towards cancer cells. Methodology/Principal Findings Peripheral blood mononuclear cells (PBMCs), isolated CD56+, CD3+, CD14+ and CD19+ subsets and different combinations of the above subsets were stimulated by delNS1, wild type (wt) virus or heat inactivated virus and co-cultured with tumor cell lines in the presence or absence of antibodies against the interferon system. Stimulation of PBMCs by the delNS1 virus effectively induced cytotoxicity against different cancer cell lines. Surprisingly, virus induced cytotoxicity was exerted by all major subtypes of PBMCs including CD56+, CD3+, CD14+ and CD19+ cells. Virus induced cytotoxicity in CD3+, CD14+ and CD19+ cells was dependent on virus replication, whereas virus induced cytotoxicity in CD56+ cells was only dependent on the binding of the virus. Virus induced cytotoxicity of isolated cell cultures of CD14+, CD19+ or CD56+ cells could be partially blocked by antibodies against type I and type II (IFN) interferon. In contrast, virus induced cytotoxicity in the complete PBMC preparation could not be inhibited by blocking type I or type II IFN, indicating a redundant system of activation in whole blood. Conclusions/Significance Our data suggest that apart from their well known specialized functions all main subsets of peripheral blood cells also initially exert a cytotoxic effect upon virus stimulation. This closely links the innate immune system to the adaptive immune response and renders delNS1 virus a potential therapeutic tool for viro-immunotherapy of cancer.

Baumann, Suzann; Kuznetsova, Irina; Spittler, Andreas; Bergmann, Michael

2009-01-01

20

Parainfluenza Viruses  

PubMed Central

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.

Henrickson, Kelly J.

2003-01-01

21

Camelpox virus.  

PubMed

Camelpox virus (CMLV) causes a smallpox-like illness in a unique host, the camel. The disease is enzootic in almost all regions where camel husbandry is practiced, and is responsible for severe economic losses. Although it is genetically the closest known virus to variola virus, the etiologic agent of smallpox, CMLV remains poorly studied. It is characterized by a narrow host range, the capacity to induce giant cells in culture and to counteract host immune defenses; however, the genetic bases associated with these features are not understood. Also, it still needs to be demonstrated whether CMLV strains of variable virulence circulate and how arthropod vectors might be involved in virus transmission. Current evidence indicates that, under certain circumstances, CMLV can be mildly pathogenic in humans. A reservoir host other than camels is unlikely to exist. We review here current knowledge of CMLV, including clinical and laboratory aspects of the disease. We also discuss prevention and therapy by use of vaccines and antiviral treatments, as well as the possibility of camelpox eradication. PMID:21945248

Duraffour, Sophie; Meyer, Hermann; Andrei, Graciela; Snoeck, Robert

2011-09-16

22

Vesicular Stomatitis Virus Disease  

NSDL National Science Digital Library

Images of Vesicular Stomatitis Virus Disease.  Vesicular stomatitis viruses (VSV) are in the family Rhabdoviridae and the genus Vesiculovirus and are enveloped viruses with bullet-shaped capsids.

American Society For Microbiology;

2007-01-09

23

Attenuated Influenza A Virus.  

National Technical Information Service (NTIS)

An attenuated influenza virus of a first strain is described together with a method for preparing the attenuated influenza virus. The attenuated influenza virus of the first strain comprises a sufficient number of single strand RNA segments of negative po...

P. Palese T. Muster B. R. Murphy M. Enami M. Bergmann

1992-01-01

24

Plant virus treatment  

US Patent & Trademark Office Database

It has been found that plant viruses and viroids can be inhibited by treating plants infected with or exposed to viruses or viroids with a virus-inhibiting amount of a maleic acid, maleic anhydride or fumaric acid copolymer.

1976-12-07

25

Preventing West Nile Virus  

MedlinePLUS

... carriers of the virus by feeding on infected birds. Although other animals have been infected with the virus—including horses, bats, squirrels, and domestic animals—birds are the most common reservoir. Once the virus ...

26

Constructing computer virus phylogenies.  

National Technical Information Service (NTIS)

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 ...

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

1996-01-01

27

Live Attenuated Herpes Simplex Virus 2 Glycoprotein E Deletion Mutant as a Vaccine Candidate Defective in Neuronal Spread  

PubMed Central

A herpes simplex virus 2 (HSV-2) glycoprotein E deletion mutant (gE2-del virus) was evaluated as a replication-competent, attenuated live virus vaccine candidate. The gE2-del virus is defective in epithelial cell-to-axon spread and in anterograde transport from the neuron cell body to the axon terminus. In BALB/c and SCID mice, the gE2-del virus caused no death or disease after vaginal, intravascular, or intramuscular inoculation and was 5 orders of magnitude less virulent than wild-type virus when inoculated directly into the brain. No infectious gE2-del virus was recovered from dorsal root ganglia (DRG) after multiple routes of inoculation; however, gE2-del DNA was detected by PCR in lumbosacral DRG at a low copy number in some mice. Importantly, no recurrent vaginal shedding of gE2-del DNA was detected in immunized guinea pigs. Intramuscular immunization outperformed subcutaneous immunization in all parameters evaluated, although individual differences were not significant, and two intramuscular immunizations were more protective than one. Immunized animals had reduced vaginal disease, vaginal titers, DRG infection, recurrent genital lesions, and recurrent vaginal shedding of HSV-2 DNA; however, protection was incomplete. A combined modality immunization using live virus and HSV-2 glycoprotein C and D subunit antigens in guinea pigs did not totally eliminate recurrent lesions or recurrent vaginal shedding of HSV-2 DNA. The gE2-del virus used as an immunotherapeutic vaccine in previously HSV-2-infected guinea pigs greatly reduced the frequency of recurrent genital lesions. Therefore, the gE2-del virus is safe, other than when injected at high titer into the brain, and is efficacious as a prophylactic and immunotherapeutic vaccine.

Zumbrun, Elizabeth E.; Si, Huaxin; Wang, Fushan; Shaw, Carolyn E.; Cai, Michael; Lubinski, John M.; Barrett, Shana M.; Balliet, John W.; Flynn, Jessica A.; Casimiro, Danilo R.; Bryan, Janine T.; Friedman, Harvey M.

2012-01-01

28

Virus Movement Maintains Local Virus Population Diversity  

SciTech Connect

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.

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

2007-11-01

29

Políticas del sitio web  

Cancer.gov

En el sitio web del NCI se proporcionan enlaces a otros sitios web con fines informativos y para conveniencia del público. Si el usuario selecciona un sitio web externo, saldrá del sitio web del NCI y estará sujeto a las políticas de privacidad y seguridad de dicho sitio.

30

Viruses in cancer treatment.  

PubMed

Soon after the discovery that viruses cause human disease, started the idea of using viruses to treat cancer. After the initial indiscriminate use, crude preparations of each novel virus in the early twentieth century, a second wave of virotherapy blossomed in the 60s with purified and selected viruses. Responses were rare and short-lived. Immune rejection of the oncolytic viruses was identified as the major problem and virotherapy was abandoned. During the past two decades virotherapy has re-emerged with engineered viruses, with a trend towards using them as tumor-debulking immunostimulatory agents combined with radio or chemotherapy. Currently, oncolytic Reovirus, Herpes, and Vaccinia virus are in late phase clinical trials. Despite the renewed hope, efficacy will require improving systemic tumor targeting, overcoming stroma barriers for virus spread, and selectively stimulating immune responses against tumor antigens but not against the virus. Virotherapy history, viruses, considerations for clinical trials, and hurdles are briefly overviewed. PMID:23143950

Alemany, R

2012-11-10

31

West Nile Virus  

Microsoft Academic Search

The West Nile virus (WNV) belongs to the genus Flavivirus (family Flaviviridae) and was previously classified as a group B\\u000a arbovirus. These disease-causing pathogens are spread to humans by insects, usually mosquitoes. Other flaviviruses include\\u000a the Yellow fever virus, Japanese encephalitis virus, dengue virus, and the Saint Louis encephalitis virus (see sections on\\u000a flaviviruses in Chapters 19 and 23). The

Vassil St. Georgiev

32

The Family of Influenza Viruses and of Pneumotropic Animal Viruses.  

National Technical Information Service (NTIS)

Influenza viruses and pneumotropic animal viruses are characterized. The morphology, pathology and immunology of these viruses are discussed. A classification of species and types is given for the pneumotropic animal viruses. The epidemiology and mode of ...

V. M. Zhadanov

1969-01-01

33

La virtualización del cuerpo a través del \\  

Microsoft Academic Search

Hablar de un cuerpo virtualizado es hablar de su problematización y consecuente actualización, una de las principales consecuencias de este proceso de transfiguración del cuerpo estaría marcada por una adjudicación actualizada de un cambio. El cuerpo es simultáneamente un cuerpo-materia prima, modelo físico para la conversión óptico-iconográfica digital, y un cuerpo interfaz, que permite el acceso a la morfogénesis del

Eduardo Castro Pinzón; José Luis Troncoso

2005-01-01

34

Dinámica del Desempeño Académico  

Microsoft Academic Search

Este trabajo se ocupa del progreso, luego del ingreso, de los estudiantes de la cohorte 2000 de la Facultad de Ciencias Económicas de la Universidad Nacional de La Plata. Si bien hay antecedentes de medición del rendimiento de los estudiantes de la Facultad y sus factores explicativos, se trata de estudios realizados en base a encuestas a alumnos regulares en

Luciano Di Gresia; Alberto Porto

2004-01-01

35

Viruses in the sea.  

PubMed

Viruses exist wherever life is found. They are a major cause of mortality, a driver of global geochemical cycles and a reservoir of the greatest genetic diversity on Earth. In the oceans, viruses probably infect all living things, from bacteria to whales. They affect the form of available nutrients and the termination of algal blooms. Viruses can move between marine and terrestrial reservoirs, raising the spectre of emerging pathogens. Our understanding of the effect of viruses on global systems and processes continues to unfold, overthrowing the idea that viruses and virus-mediated processes are sidebars to global processes. PMID:16163346

Suttle, Curtis A

2005-09-15

36

Viruses in the sea  

NASA Astrophysics Data System (ADS)

Viruses exist wherever life is found. They are a major cause of mortality, a driver of global geochemical cycles and a reservoir of the greatest genetic diversity on Earth. In the oceans, viruses probably infect all living things, from bacteria to whales. They affect the form of available nutrients and the termination of algal blooms. Viruses can move between marine and terrestrial reservoirs, raising the spectre of emerging pathogens. Our understanding of the effect of viruses on global systems and processes continues to unfold, overthrowing the idea that viruses and virus-mediated processes are sidebars to global processes.

Suttle, Curtis A.

2005-09-01

37

Chimeric Dengue Viruses.  

National Technical Information Service (NTIS)

The invention relates, in general, to chimeric dengue viruses. In particular, the invention relates to chimeric dengue viruses and vaccines comprising same. Further, the invention relates to segments of dengue viral DNA.

C. J. Lai M. Bray

1991-01-01

38

Advances in virus research  

SciTech Connect

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.

Maramorosch, K. (Rutgers--the State Univ., New Brunswick, NJ (USA)); Murphy, F.A. (Centers for Disease Control, Atlanta, GA (USA)); Shatkin, A.J. (Rutgers-UMDNJ, Piscataway, NJ (US))

1988-01-01

39

Human B Lymphotropic Virus.  

National Technical Information Service (NTIS)

The invention is related generally to the isolation and characterization of a new virus. More particularly, it is related to providing a biologically pure, isolated human B lymphotropic virus, molecular clones, nucleic acid, distinctive antigenic proteins...

S. Salahuddin

1988-01-01

40

Viruses and human cancer  

SciTech Connect

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

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

1987-01-01

41

Viruses and cancer  

SciTech Connect

This book contains 14 selections. Some of the titles are: Immortalising gene(s) encoded by Epstein-Barr Virus; Adenovirus genes involved in transformation. What determines the oncogenic phenotype.; Oncogenesis by mouse mammary tumour virus; and Transforming ras genes.

Rigby, P.W.J.; Wilkie, N.M.

1985-01-01

42

West Nile Virus  

NSDL National Science Digital Library

Good introduction and synopsis of West Nile Virus. Briefly reporting on such topics as geographic distribution, symptoms and treatment, transmission and prevention. The article includes a list of references for further investigation into the West Nile Virus.

0002-11-30

43

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 ...

44

West Nile Virus  

MedlinePLUS

West Nile virus (WNV) is an infectious disease that first appeared in the United States in 1999. Infected ... and usually go away on their own. If West Nile virus enters the brain, however, it can be ...

45

West Nile Virus  

MedlinePLUS

... West Nile virus has been found in animals, birds, and humans in all continental states in the ... picked up the virus after feeding on infected birds. Pets and other animals can also become infected ...

46

An Undetectable Computer Virus  

Microsoft Academic Search

One of the few solid theoretical results in the study of computer viruses is Cohen's 1987 demonstration that there is no algorithm that can perfectly detect all possible viruses [1]. This brief paper adds to the bad news, by pointing out that there are computer viruses which no algorithm can detect, even under a somewhat more liberal definition of detection.

David M. Chess; Steve R. White

2000-01-01

47

EFECTO SOBRE LA SARNA POLVOSA DE CUATRO AISLAMIENTOS DEL HONGO Trichoderma asperellum EN TRES TIPOS DE SUELO EFFECT ON THE POWDERY SCAB OF FOUR ISOLATES OF THE FUNGUS Trichoderma asperellum IN THREE TYPES OF SOILS  

Microsoft Academic Search

The protozoan Spongospora subterranea f. sp. subterranea is an obligate parasite that replicates in roots and tubers of potato causing the powdery scab. This disease has disseminated on a global scale, because the commercial traffic of infected tubers used as seed and the absence of effective treatments. The present work investigated the effects of four isolates of Trichoderma asperellum in

Elizabeth Gilchrist; Sonia Jaramillo Villegas; Sebastián Reynaldi

48

[Viruses as biological weapons].  

PubMed

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

Akçali, Alper

2005-07-01

49

Overview of Musa virus diseases  

Microsoft Academic Search

Bananas and other Musa spp. are affected by fi ve known, relatively well-characterized viruses: these are Banana bunchy top virus (BBTV) genus Nanavirus; Banana streak virus (BSV) genus Badnavirus, Cucumber mosaic virus (CMV) genus Cucumovi- rus, Banana bract mosaic virus (BBrMV) genus Potyvirus, and Abaca mosaic virus (AbaMV) genus Potyvirus. Recently, new fi lamentous virus particles have been noted in

G. Pietersen; J. E. Thomas

50

Lipids of Archaeal Viruses  

PubMed Central

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.

Roine, Elina; Bamford, Dennis H.

2012-01-01

51

Elastic Properties of Viruses  

PubMed Central

Viruses are compact biological nanoparticles whose elastic and dynamical properties are hardly known. Inelastic (Brillouin) light scattering was used to characterize these properties, from microcrystals of the Satellite Tobacco Mosaic Virus, a nearly spherical plant virus of 17-nm diameter. Longitudinal sound velocities in wet and dry Satellite Tobacco Mosaic Virus crystals were determined and compared to that of the well-known protein crystal, lysozyme. Localized vibrational modes of the viral particles (i.e., particle modes) were sought in the relevant frequency ranges, as derived assuming the viruses as full free nanospheres. Despite very favorable conditions, regarding virus concentration and expected low damping in dry microcrystals, no firm evidence of virus particle modes could be detected.

Stephanidis, B.; Adichtchev, S.; Gouet, P.; McPherson, A.; Mermet, A.

2007-01-01

52

The Acute bee paralysis virus–Kashmir bee virus–Israeli acute paralysis virus complex  

Microsoft Academic Search

Acute bee paralysis virus (ABPV), Kashmir bee virus (KBV) and Israeli acute paralysis virus (IAPV) are part of a complex of closely related viruses from the Family Dicistroviridae. These viruses have a widespread prevalence in honey bee (Apis mellifera) colonies and a predominantly sub-clinical etiology that contrasts sharply with the extremely virulent pathology encountered at elevated titres, either artificially induced

Joachim R. de Miranda; Guido Cordoni; Giles Budge

2010-01-01

53

Viruses in Antarctic lakes.  

PubMed

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. PMID:11543124

Kepner, R L; Wharton, R A; Suttle, C A

1998-11-01

54

Constructing computer virus phylogenies  

SciTech Connect

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.

Goldberg, L.A. [Warwick Univ., Coventry (United Kingdom) Dept. of Computer Science; Goldberg, P.W. [Aston Univ., Birmingham (United Kingdom) Dept. of Applied Mathematics; Phillips, C.A. [Sandia National Labs., Albuquerque, NM (United States); Sorkin, G.B. [International Business Machines Corp., Yorktown Heights, NY (United States). Thomas J. Watson Research Center

1996-03-01

55

Recombinant vaccinia viruses  

Microsoft Academic Search

The technologies of recombinant gene expression have greatly enhanced the structural and functional analyses of genetic elements\\u000a and proteins. Vaccinia virus, a large double-stranded DNA virus and the prototypic and best characterized member of the poxvirus\\u000a family, has been an instrumental tool among these technologies and the recombinant vaccinia virus system has been widely employed\\u000a to express genes from eukaryotic,

Christopher C. Broder; Patricia L. Earl

1999-01-01

56

Origins of Viruses  

NSDL National Science Digital Library

This page contains lecture notes on the origins and evolution of viruses. The primary topics covered are the diversity of extant viruses, the probability of multiple origins, and host-virus co-evolution. There are links to definitions and further explanations by the author, as well as to articles or discussions in Scientific American, MicrobiologyBytes, and Viroblogy. This page originates from an undergraduate course, but most information would be accessible to high school students.

Rybicki, Ed; Town, University O.

57

Viruses in artichoke.  

PubMed

Most of the 25 viruses found in globe artichoke (Cynara scolymus L.) and cardoon (Cynara cardunculus L.) were recorded from Europe and the Mediterranean basin, where they decrease both the productivity and the quality of the crop. Although, sometimes, these viruses are agents of diseases of different severity, most often their infections are symptomless. These conditions have contributed to spread virus-infected material since farmers multiply traditional artichoke types vegetatively with no effective selection of virus-free plants. This review reports the main properties of these viruses and the techniques used for their detection and identification. ELISA kits are commercially available for most of the viruses addressed in this review but have seldom been used for their detection in artichoke. Conversely, nucleic acid-based diagnostic reagents, some of which are commercially available, have successfully been employed to identify some viruses in artichoke sap. Control measures mainly use virus-free stocks for new plantations. A combined procedure of meristem-tip culture and thermotherapy proved useful for producing virus-free regenerants of the reflowering southern Italian cultivar Brindisino, which kept earliness and typical heads shape. PMID:22682171

Gallitelli, Donato; Mascia, Tiziana; Martelli, Giovanni P

2012-01-01

58

CDC: West Nile Virus  

NSDL National Science Digital Library

This Web site contains the most recent West Nile virus data from the Centers for Disease Control. The main features include a 2003 Human Case Count and updated maps representing the spread of the virus. A downloadable document outlines the CDC's West Nile virus surveillance and control program, which involves weekly data collection for wild birds, sentinel chicken flocks, human cases, veterinary cases, and mosquito surveillance. The site also provides links to general information about the virus, from the ecology and virology of West Nile to epidemiological and laboratory issues.

2008-06-26

59

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

PubMed Central

Influenza viruses unable to express NS1 protein (delNS1) replicate poorly and induce large amounts of interferon (IFN). They are therefore considered candidate viruses for live-attenuated influenza vaccines. Their attenuated replication is generally assumed to result from the inability to counter the antiviral host response, as delNS1 viruses replicate efficiently in Vero cells, which lack IFN expression. In this study, delNS1 virus was parallel passaged on IFN-competent MDCK cells, which resulted in two strains that were able to replicate to high virus titers in MDCK cells due to adaptive mutations especially in the M-gene segment but also in the NP and NS gene segments. Most notable were clustered U-to-C mutations in the M segment of both strains and clustered A-to-G mutations in the NS segment of one strain, which presumably resulted from host cell-mediated RNA editing. The M segment mutations in both strains changed the ratio of M1 to M2 expression, probably by affecting splicing efficiency. In one virus, 2 amino acid substitutions in M1 additionally enhanced virus replication, possibly through changes in the M1 distribution between the nucleus and the cytoplasm. Both adapted viruses induced levels of IFN equal to that of the original delNS1 virus. These results show that the increased replication of the adapted viruses is not primarily due to altered IFN induction but rather is related to changes in M1 expression or localization. The mutations identified in this paper may be used to enhance delNS1 virus replication for vaccine production.

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

2012-01-01

60

Asociación entre el virus XMRV y enfermedades humanas: preguntas y respuestas  

Cancer.gov

El XMRV es un retrovirus del que se informó por primera vez en 2006 como una causa potencial del cáncer de próstata. Está estrechamente relacionado con los virus de leucemia murina, los cuales causan una amplia variedad de cánceres así como enfermedades inmunológicas y neurológicas en ratones.

61

Boletín del Instituto Nacional del Cáncer - 07-20-2010  

Cancer.gov

El doctor Harold Varmus, acompañado de su esposa Constance Casey (centro), presta juramento como director del NCI ante la Secretaria del Departamento de Salud y Servicios Humanos, Kathleen Sebelius, el lunes 12 de julio. (Foto cortesía de Chris Smith) El 12 de julio, el doctor Harold Varmus prestó juramento ante la Secretaria del Departamento de Salud y Servicios Humanos de los Estados Unidos, Kathleen Sebelios, como el decimocuarto director del Instituto Nacional del Cáncer.

62

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 ...

63

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...

64

Computer Virus Propagation Models  

Microsoft Academic Search

The availability of reliable models of computer virus propa- gation would prove useful in a number of ways, in order both to predict future threats, and to develop new containment measures. In this pa- per, we review the most popular models of virus propagation, analyzing the underlying assumptions of each of them, their strengths and their weaknesses. We also introduce

Giuseppe Serazzi; Stefano Zanero

2003-01-01

65

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...

66

Recombination in AIDS viruses  

Microsoft Academic Search

Recombination contributes to the generation of genetic diversity in human immunodeficiency viruses (HIV) but can only occur between viruses replicating within the same cell. Since individuals have not been found to be simultaneously coinfected with multiple divergent strains of HIV-1 or HIV-2, recombination events have been thought to be restricted to the rather closely related members of the quasispecies that

David L. Robertson; Beatrice H. Hahn; Paul M. Sharp

1995-01-01

67

Deformed wing virus  

Microsoft Academic Search

Deformed wing virus (DWV; Iflaviridae) is one of many viruses infecting honeybees and one of the most heavily investigated due to its close association with honeybee colony collapse induced by Varroadestructor. In the absence of V.destructor DWV infection does not result in visible symptoms or any apparent negative impact on host fitness. However, for reasons that are still not fully

Joachim R. de Miranda; Elke Genersch

2010-01-01

68

What is a Virus?  

NSDL National Science Digital Library

This page is part of a web site that was created as a tutorial for an introductory virology class for college level microbiology students. It includes links to definitions of virus, virions, other virus-like-agents, and organisms, as well as the "definition of life".

Rybicki, Ed

2010-03-23

69

The hepatitis B virus  

Microsoft Academic Search

DNA recombinant technology has radically changed hepatitis B virus (HBV) virology. The genetic organization, transcription and replication of the virus are basically understood, structures of integrated HBV sequences in hepatocellular carcinoma have been characterized, and new vaccines produced by recombinant DNA technique are being developed.

Pierre Tiollais; Christine Pourcel; Anne Dejean

1985-01-01

70

Human Papilloma Virus Infections  

PubMed Central

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.

Wright, V. Cecil

1989-01-01

71

Virus persistence in groundwater.  

PubMed Central

More than 50% of the outbreaks of waterborne disease in the United States are due to the consumption of contaminated groundwater. An estimated 65% of the cases in these outbreaks are caused by enteric viruses. Little, however, is known about the persistence of viruses in groundwater. The purpose of this study was to determine whether measurable chemical and physical factors correlate with virus survival in groundwater. Groundwater samples were obtained from 11 sites throughout the United States. Water temperature was measured at the time of collection. Several physical and chemical characteristics, including pH, nitrates, turbidity, and hardness, were determined for each sample. Separate water samples were inoculated with each of three viruses (poliovirus 1, echovirus 1, and MS-2 coliphage) and incubated at the in situ groundwater temperature; selected samples were also incubated at other temperatures. Assays were performed at predetermined intervals over a 30-day period to determine the number of infective viruses remaining. Multiple regression analysis revealed that temperature was the only variable significantly correlated with the decay rates of all three viruses. No significant differences were found among the decay rates of the three viruses, an indication that MS-2 coliphage might be used as a model of animal virus survival in groundwater.

Yates, M V; Gerba, C P; Kelley, L M

1985-01-01

72

Giant Viruses: Conflicts in Revisiting the Virus Concept  

Microsoft Academic Search

The current paradigm on the nature of viruses is based on early work of the ‘phage group’ (the pro-phage concept) and molecular biologists working on tumour viruses (the proto-oncogene concept). It posits that viruses evolved from either prokaryotic or eukaryotic cellular genes that became infectious via their association with capsid genes. In this view, after their emergence viruses continued to

Patrick Forterre

2010-01-01

73

Schmallenberg Virus as Possible Ancestor of Shamonda Virus  

PubMed Central

Schmallenberg virus (SBV), an orthobunyavirus of the Simbu serogroup, recently emerged in Europe and has been suggested to be a Shamonda/Sathuperi virus reassortant. Results of full-genome and serologic investigations indicate that SBV belongs to the species Sathuperi virus and is a possible ancestor of the reassortant Shamonda virus.

Goller, Katja V.; Hoper, Dirk; Schirrmeier, Horst; Mettenleiter, Thomas C.

2012-01-01

74

El pronóstico del cáncer  

Cancer.gov

Hoja informativa sobre la predicción de resultados y recuperación de una enfermedad, y sobre cómo las estadísticas ayudan a los médicos a hacer una estimación del pronóstico de un paciente con cáncer.

75

Cytosolic sensing of viruses.  

PubMed

Cells are equipped with mechanisms that allow them to rapidly detect and respond to viruses. These defense mechanisms rely partly on receptors that monitor the cytosol for the presence of atypical nucleic acids associated with virus infection. RIG-I-like receptors detect RNA molecules that are absent from the uninfected host. DNA receptors alert the cell to the abnormal presence of that nucleic acid in the cytosol. Signaling by RNA and DNA receptors results in the induction of restriction factors that prevent virus replication and establish cell-intrinsic antiviral immunity. In light of these formidable obstacles, viruses have evolved mechanisms of evasion, masking nucleic acid structures recognized by the host, sequestering themselves away from the cytosol or targeting host sensors, and signaling adaptors for deactivation or degradation. Here, we detail recent advances in the molecular understanding of cytosolic nucleic acid detection and its evasion by viruses. PMID:23706667

Goubau, Delphine; Deddouche, Safia; Reis E Sousa, Caetano

2013-05-23

76

Virus discovery and recent insights into virus diversity in arthropods.  

PubMed

Recent studies on virus discovery have focused mainly on mammalian and avian viruses. Arbovirology with its long tradition of ecologically oriented investigation is now catching up, with important novel insights into the diversity of arthropod-associated viruses. Recent discoveries include taxonomically outlying viruses within the families Flaviviridae, Togaviridae, and Bunyaviridae, and even novel virus families within the order Nidovirales. However, the current focusing of studies on blood-feeding arthropods has restricted the range of arthropod hosts analyzed for viruses so far. Future investigations should include species from other arthropod taxa than Ixodita, Culicidae and Phlebotominae in order to shed light on the true diversity of arthropod viruses. PMID:23850098

Junglen, Sandra; Drosten, Christian

2013-07-11

77

Il problema del litio.  

NASA Astrophysics Data System (ADS)

Contents: 1. Introduzione. 2. La nucleosintesi del Big Bang. 3. Il litio nelle stelle di popolazione II. 4. I modelli stellari standard. 5. Il litio negli ammassi aperti. 6. Meccanismi di distruzione "non standard". 7. I modelli non-standard applicati alla popolazione II. 8. L'evoluzione Galattica del litio. 9. Quali stelle producono litio? 10. Il litio come elemento chiave per dare un nome agli oggetti stellari più minuscoli. 11. Conclusioni.

D'Antona, F.

1995-03-01

78

Fisiopatología del estreñimiento  

Microsoft Academic Search

ResumenEl estreñimiento es un trastorno extremadamente frecuente en la infancia, responsable de hasta el 25% de todas las consultas gastroenterológicas pediátricas y el 3% de todas las consultas pediátricas ambulatorias. En el 90% de los casos el origen del trastorno es funcional y sólo en un 10% existe un problema orgánico subyacente. Entre las causas orgánicas corrientes del estreñimiento infantil

Peter J. Milla

2007-01-01

79

Realms of the Viruses Online  

ERIC Educational Resources Information Center

|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…

Liu, Dennis

2007-01-01

80

Hepatitis B Virus in Pregnancy  

MedlinePLUS

What is hepatitis B virus? Hepatitis B virus is one of a number of hepatitis viruses that attack and damage the liver. Other types include hepatitis A, ... upper-right side of your abdomen. How is hepatitis B transmitted? Hepatitis B virus is passed from ...

81

Oncolytic viruses in cancer therapy.  

PubMed

Oncolytic virotherapy is a promising form of gene therapy for cancer, employing nature's own agents to find and destroy malignant cells. The purpose of this review is to provide an introduction to this very topical field of research and to point out some of the current observations, insights and ideas circulating in the literature. We have strived to acknowledge as many different oncolytic viruses as possible to give a broader picture of targeting cancer using viruses. Some of the newest additions to the panel of oncolytic viruses include the avian adenovirus, foamy virus, myxoma virus, yaba-like disease virus, echovirus type 1, bovine herpesvirus 4, Saimiri virus, feline panleukopenia virus, Sendai virus and the non-human coronaviruses. Although promising, virotherapy still faces many obstacles that need to be addressed, including the emergence of virus-resistant tumor cells. PMID:17383089

Vähä-Koskela, Markus J V; Heikkilä, Jari E; Hinkkanen, Ari E

2007-03-23

82

Tracking a Virus  

NSDL National Science Digital Library

Students simulate the spread of a virus such as HIV through a population by âsharingâ (but not drinking) the water in a plastic cup with several classmates. Although invisible, the water in a few of the cups will already be tainted with the âvirusâ (sodium carbonate). After all the students have shared their liquids, the contents of the cups will be tested for the virus with phenolphthalein, a chemical that causes a striking color change in the presence of sodium carbonate. Students will then set about trying to determine which of their classmates were the ones originally infected with the virus.

Engineering K-Ph.d. Program

83

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

Code of Federal Regulations, 2010 CFR

...Diarrhea Vaccine, Killed Virus. Bovine Virus Diarrhea Vaccine...this paragraph. (i) Eight bovine virus diarrhea susceptible...after the last vaccination, blood samples shall be drawn and the...samples inactivated and tested for bovine virus diarrhea virus...

2009-01-01

84

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

Code of Federal Regulations, 2010 CFR

...Diarrhea Vaccine, Killed Virus. Bovine Virus Diarrhea Vaccine...this paragraph. (i) Eight bovine virus diarrhea susceptible...after the last vaccination, blood samples shall be drawn and the...samples inactivated and tested for bovine virus diarrhea virus...

2010-01-01

85

Transmisión vertical del VIH  

Microsoft Academic Search

SUMMARY Prevention of perinatal transmission of the human immunodeficency virus is a major goal in the manage- ment of pregnant women infected with HIV. Effectiveness of zidovudine as a preventive agent has been pro- bably one of the most important advances in this regard. Later evidence has shown the benefit of employing combination antiretroviral therapy in reducing the transmission as

C. Martí; A. Guntiñas; C. Sanz; G. Vegas; I. Bates; J. M. Peña; R. Usandizaga

2002-01-01

86

The dengue viruses.  

PubMed Central

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

Henchal, E A; Putnak, J R

1990-01-01

87

Virus Ultra Structure  

NSDL National Science Digital Library

Linda Stannard of the University of Capetown, South Africa, has composed a page which, although it was intended to serve as an introductory manual for students of virology, can be appreciated by a wide audience. A section on the principles of virus architecture uses text and outstanding graphics to provide an introduction to why viruses look the way they do. Other parts of the site emphasize how virus shapes and structures are "seen" and recorded with sections on negative staining and electron microscopy of DNA- and RNA-containing viruses. This site's success relies on the use of well-chosen graphics and the inclusion of interesting factoids such as the following: "The head of a dress-maker's pin can provide seating accommodation for five hundred million rhinoviruses (cause of the common cold)!".

88

Influenza Virus Vaccine Actions  

Center for Biologics Evaluation and Research (CBER)

... Approval of new bulk manufacturing facility for production of Influenza Virus Vaccine. -. Key Resources. ... Key Links. Flu.gov. -. Contact FDA. ... More results from www.fda.gov/biologicsbloodvaccines/safetyavailability/vaccinesafety

89

Rubella Virus Vaccine Live  

Center for Biologics Evaluation and Research (CBER)

... Rubella Virus Vaccine Live. -. Product. MERUVAX II Merck & Co, Inc. -. Contact FDA. (800) 835-4709. (301) 827-1800. ocod ... More results from www.fda.gov/biologicsbloodvaccines/vaccines/approvedproducts

90

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...

91

What's West Nile Virus?  

MedlinePLUS

... Baseball Injuries Jellyfish The Pink Locker Society What's West Nile Virus? KidsHealth > Kids > Illnesses & Injuries > Aches, Pains & Injuries > ... are most at risk for the infection. Continue West Nile Symptoms Most of the time, symptoms of West ...

92

Selective Precipitation of Viruses.  

National Technical Information Service (NTIS)

The invention provides new methods for purifying and concentrating viruses. The inventors have discovered that high molecular weight proteoglycans present in retroviral stocks are co-concentrated with the retroviruses, and can inhibit retroviral transduct...

J. M. LeDoux M. L. Yarmush J. R. Morgan

2005-01-01

93

Respiratory syncytial virus (RSV)  

MedlinePLUS

... often spreads very rapidly 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 ...

94

AVG Anti-Virus  

NSDL National Science Digital Library

Those who wish for an antivirus program that is both versatile and reliable should definitely consider this latest iteration of the AVG Anti-Virus program. With this program, visitors can be assured that AVG will look for new virus definitions on a daily basis and that it will also create an effective rescue disk in case a dire situation emerges. This website features a number of archived versions of the AVG software for users to choose from.

2008-01-01

95

West nile virus encephalitis  

Microsoft Academic Search

West Nile virus (WNV) is a small RNA virus. It was first isolated in the blood of a febrile woman in the West Nile district\\u000a of Uganda in 1937. Although WNV has caused human disease in Africa and Europe since its identification, the first documented\\u000a human infections occurred in the United States in 1999. Wild birds are the reservoir for

James L. Dean; Brandon J. Palermo

2005-01-01

96

Bacterial Indicators of Viruses  

Microsoft Academic Search

The association between human enteric viruses and disease is well established. However, determining the presence of all of\\u000a the many types of viruses that are pathogenic to humans in food and water is not practical at this time. Because enteric bacteria\\u000a are usual inhabitants of the human intestinal tract, they have been used as indicators of fecal pollution and the

Samuel R. Farrah

97

Oncogenic Viruses of Nonhuman Primates: A Review.  

National Technical Information Service (NTIS)

Oncogenic viruses of nonhuman primates were reviewed. Viruses of nonhuman primate origin oncogenic in other nonhuman primates includes Herpesvirus saimiri and ateles, simian sarcoma virus, Yaba poxvirus, and oral papilloma virus. SV-40 and simian adenovir...

C. P. Raflo

1975-01-01

98

Clarifying Bunyamwera virus riddles of the past.  

PubMed

Pyrosequencing data and phylogenetic analysis for the full genome of Ilesha virus, Ngari virus and Calovo virus are described clarifying their much discussed relationship within the species Bunyamwera virus of the genus Orthobunyavirus of the Bunyaviridae. PMID:23686694

Dilcher, Meik; Sall, Amadou A; Hufert, Frank T; Weidmann, Manfred

2013-05-18

99

Molecular detection of respiratory viruses.  

PubMed

Over the past several years a wide variety of molecular assays for the detection of respiratory viruses has reached the market. The tests described herein range from kits containing primers and probes detecting specific groups of viruses, to self-contained systems requiring specialized instruments that extract nucleic acids and perform the polymerase chain reaction with little operator input. Some of the tests target just the viruses involved in large yearly epidemics such as influenza, or specific groups of viruses such as the adenoviruses or parainfluenza viruses; others can detect most of the known respiratory viruses and some bacterial agents. PMID:23931834

Buller, Richard S

2013-09-01

100

Recombinant Vaccinia Virus: Immunization against Multiple Pathogens  

NASA Astrophysics Data System (ADS)

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.

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

1985-09-01

101

Bovine Leukemia Virus: An Exogenous RNA Oncogenic Virus  

Microsoft Academic Search

Short-term cultures of bovine leukemic lymphocytes release virus particles with biochemical properties of RNA oncogenic viruses. These particles, tentatively called bovine leukemia virus (BLV), have a high molecular weight RNA-reverse transcriptase complex and a density of 1.155 g\\/ml in sucrose solutions. Molecular hybridizations between BLV [3H]cDNA and several viral RNAs show that BLV is not related to Mason-Pfizer monkey virus,

R. Kettmann; D. Portetelle; M. Mammerickx; Y. Cleuter; D. Dekegel; M. Galoux; J. Ghysdael; A. Burny; H. Chantrenne

1976-01-01

102

Maternal recognition of foetal infection with bovine virus diarrhoea virus (BVDV)—the bovine pestivirus  

Microsoft Academic Search

Background: Pestiviruses are the veterinary viruses with genome homology to human hepatitis C virus (HCV). This group includes classical swine fever virus (CSFV), border disease virus of sheep (BDV) and bovine virus diarrhoea virus (BVDV). There are some similarities in the pathology of all three virus infections; in utero transmission to the foetus can cause early embryonic losses, severe congenital

J Brownlie; L. B Hooper; I Thompson; M. E Collins

1998-01-01

103

Pseudotypes of Vesicular Stomatitis Virus with the Coat of Murine Leukaemia and of Avian Myeloblastosis Viruses  

Microsoft Academic Search

SUMMARY Vesicular stomatitis virus (VSV) grown in mouse embryo cells pre-infected with murine sarcoma virus or in chicken cells pre-infected with avian myeloblastosis virus contains, in contrast to virus grown in corresponding control cells, a proportion of virus resistant to antiserum against VSV. Infectivity of this virus fraction can specifically be neutralized with antiserum against murine leukaemia virus (MLV) and

J. Zavada

1972-01-01

104

Immunology of hepatitis B virus and hepatitis C virus infection  

Microsoft Academic Search

More than 500 million people worldwide are persistently infected with the hepatitis B virus (HBV) and\\/or hepatitis C virus (HCV) and are at risk of developing chronic liver disease, cirrhosis and hepatocellular carcinoma. Despite many common features in the pathogenesis of HBV- and HCV-related liver disease, these viruses markedly differ in their virological properties and in their immune escape and

Michelina Nascimbeni; Barbara Rehermann

2005-01-01

105

Glycyrrhizic acid inhibits virus growth and inactivates virus particles  

Microsoft Academic Search

Screening investigations in antiviral action of plant extracts have revealed that a component of Glycyrrhiza glabra roots, found to be glycyrrhizic acid, is active against viruses. We report here that this drug inhibits growth and cytopathology of several unrelated DNA and RNA viruses, while not affecting cell activity and ability to replicate. In addition, glycyrrhizic acid inactivates herpes simplex virus

Raffaello Pompei; Ornella Flore; Maria Antonietta Marccialis; Alessandra Pani; Bernardo Loddo

1979-01-01

106

Control del cáncer y salud mundial: noticia del Instituto Nacional del Cáncer (NCI)  

Cancer.gov

En combinación con una reunión de alto nivel de las Naciones Unidas sobre enfermedades no transmisibles en países en vías de desarrollo, el doctor Harold Varmus, director del NCI, y el doctor Ted L. Trimble, del NCI, han publicado un comentario en Science Translational Medicine sobre “La integración del control del cáncer en la salud mundial" (Integrating Cancer Control into Global Health).

107

Emerging issues in virus taxonomy.  

PubMed

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

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

2004-01-01

108

Studies Relating to Virus Control.  

National Technical Information Service (NTIS)

Contents: Fifty years' effort to control virus infections in the USSR; Thirtieth anniversary of the discovery of the causative agent of tick-borne encephalitis; Relationship between the effect of ionizing radiation on the course of virus infections and th...

O. V. Baroyan E. N. Levkovich A. G. Moroz

1968-01-01

109

Replication of Japanese Encephalitis Virus.  

National Technical Information Service (NTIS)

Gene expression in the flavivirus Japanese encephalitis virus (JEV) was studied by three different approaches. Virus-specific RNA in infected cells was radiolabeled in the presence of actinomycin D, and analyzed by sucrose gradient sedimentation and agaro...

C. D. Blair

1981-01-01

110

Respiratory syncytial virus bronchiolitis.  

PubMed Central

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.

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

2005-01-01

111

Diagnosis of influenza virus.  

PubMed

The laboratory diagnosis of influenza uses a wide range of techniques including rapid immunoassays, immunofluorescence techniques, virus culture methods, and increasingly sophisticated molecular assays. The potential utility of each of these methods has changed over the years, most dramatically perhaps with the emergence of the pandemic H1N1 2009 influenza virus. While rapid immunoassays had previously been widely used in clinics and emergency departments, their poor detection sensitivity for the 2009 subtype brought their application into question. Concerns were also raised about the detection sensitivities of antibody reagents used in immunofluorescence methods, and the safety of virus culture was initially questioned with regard to the newly emerged subtype. Early molecular detection techniques had been labor intensive, and required separate facilities in order to prevent contamination. Those techniques have largely been supplanted by more modern methods, most notably real-time reverse transcription PCR assays, which are currently the method of choice in many laboratories for the detection and subtyping of influenza viruses. Suspension and low-density array assays are also increasingly used, in an effort to detect larger numbers of viruses in a single assay, and microarrays have proven valuable for outbreak analysis and pathogen discovery. Each laboratory must assess the optimal methods for its situation and the best application of each technique, taking into account numerous factors including its budget, equipment, staff expertise, the patient population that it serves, the needs of its submitting clinicians, and its surveillance and public health responsibilities. PMID:22528153

George, Kirsten St

2012-01-01

112

Molluscum contagiosum virus infection.  

PubMed

Molluscum contagiosum virus is an important human skin pathogen: it can cause disfigurement and suffering in children, in adults it is less common and often sexually transmitted. Extensive and persistent skin infection with the virus can indicate underlying immunodeficiency. Traditional ablative therapies have not been compared directly with newer immune-modulating and specific antiviral therapies. Advances in research raise the prospect of new approaches to treatment informed by the biology of the virus; in human skin, the infection is localised in the epidermal layers, where it induces a typical, complex hyperproliferative lesion with an abundance of virus particles but a conspicuous absence of immune effectors. Functional studies of the viral genome have revealed effects on cellular pathways involved in the cell cycle, innate immunity, inflammation, and cell death. Extensive lesions caused by molluscum contagiosum can occur in patients with DOCK8 deficiency-a genetic disorder affecting migration of dendritic and specialised T cells in skin. Sudden disappearance of lesions is the consequence of a vigorous immune response in healthy people. Further study of the unique features of infection with molluscum contagiosum virus could give fundamental insight into the nature of skin immunity. PMID:23972567

Chen, Xiaoying; Anstey, Alex V; Bugert, Joachim J

2013-08-21

113

Infectious salmon anaemia virus.  

PubMed

Infectious salmon anaemia virus (ISAV) is a commercially important orthomyxovirus causing disease in farmed Atlantic salmon. The cumulative mortality in a net pen during an outbreak may vary from insignificant to more than 90%. The infection is spread by management activity such as well-boat traffic, but possibly also through contact with wild fish. In many of its aspects, including the structure of the virus particle and replication strategy, the ISAV is similar to the influenza viruses. Variations between ISAV and the influenza viruses can mostly be related to differences in the temperature at which replication occurs and the immune response of their respective host animals. ISAV shows both haemagglutinating and receptor-destroying activity. The variability of the ISAV haemagglutinin molecule is concentrated around a small domain close to the transmembrane region. The function of this variable region is unknown, but it may be related to a recent or ongoing crossing of a species barrier. Alignment studies based on genetic data indicate that the phylogenetic relationship to the influenza viruses is distant, and that ISAV therefore could possibly warrant a new genus within Orthomyxoviridae. PMID:12076262

Rimstad, Espen; Mjaaland, Siri

2002-04-01

114

Dissecting virus entry via endocytosis  

Microsoft Academic Search

Numerous virus families utilize endocytosis to infect host cells, mediating virus internalization as well as trafficking to the site of replication. Recent research has demonstrated that viruses employ the full endocytic capabilities of the cell. The endocytic pathways utilized include clathrin-mediated endocytosis, caveolae, macropinocytosis and novel non-clathrin, non-caveolae pathways. The tools to study endocytosis and, consequently, virus entry are becoming

Sara B. Sieczkarski; Gary R. Whittaker

2002-01-01

115

Virus load and antigenic diversity  

Microsoft Academic Search

In this paper, we analyse mathematical models for the interaction between virus replication and immune responses. We show\\u000a that the immune system can provide selection pressure for or against viral diversity. The paper provides new insights into\\u000a the relationship between virus load (=the abundance of virus in an infected individual) and antigenic diversity. Antigenic\\u000a variation can increase virus load during

Barbara Bittner; Sebastian Bonhoeffer; Martin A. Nowak

1997-01-01

116

Measles Virus for Cancer Therapy  

Microsoft Academic Search

Measles virus offers an ideal platform from which to build a new generation of safe, effective oncolytic viruses. Occasional\\u000a so-called spontaneous tumor regressions have occurred during natural measles infections, but common tumors do not express\\u000a SLAM, the wild-type MV receptor, and are therefore not susceptible to the virus. Serendipitously, attenuated vaccine strains\\u000a of measles virus have adapted to use CD46,

S. J. Russell; K. W. Peng

117

Nipah virus outbreak in Malaysia  

Microsoft Academic Search

Nipah virus, a novel paramyxovirus, closely related to Hendra virus emerged in northern part of Peninsular Malaysia in 1998. The virus caused an outbreak of severe febrile encephalitis in humans with a high mortality rate, whereas, in pigs, encephalitis and respiratory diseases but with a relatively low mortality rate. The outbreak subsequently spread to various regions of the country and

Kaw Bing Chua

2003-01-01

118

Virus Evolution and Population Dynamics  

Microsoft Academic Search

It is intuitive that the field of virology is a discipline integral to the medical sciences. The affiliation of virology with population and conservation biology may not be as apparent. However, viruses, and in particular, virus evolution, may both contribute to and be a significant tool to understand changes in host population structure. The impact of viruses is most notable

Mary Poss; Roman Biek; Allen Rodrigo

119

An introduction to computer viruses  

SciTech Connect

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.

Brown, D.R.

1992-03-01

120

Soy isoflavones and virus infections  

Microsoft Academic Search

Isoflavones and their related flavonoid compounds exert antiviral properties in vitro and in vivo against a wide range of viruses. Genistein is, by far, the most studied soy isoflavone in this regard, and it has been shown to inhibit the infectivity of enveloped or nonenveloped viruses, as well as single-stranded or double-stranded RNA or DNA viruses. At concentrations ranging from

Aline Andres; Sharon M. Donovan; Mark S. Kuhlenschmidt

2009-01-01

121

Raspberry latent virus in Rubus  

Technology Transfer Automated Retrieval System (TEKTRAN)

Raspberry latent virus (RpLV) is a recently characterized virus reported from the Pacific Northwest, including Oregon and Washington in the United States and British Columbia in Canada. The virus appears to spread rapidly in the Fraser River Valley (northwest Washington and southwest British Columb...

122

Epidemiological Studies of Amapari Virus.  

National Technical Information Service (NTIS)

A new virus, named Amapari virus, was isolated from forest rodents and their mites caught in Amapa, Brazil. Through August 1970, more than 350 isolations of MAPARI VIRUS HAVE BEEN MADE, FROM 204/1896 RODENTS OF ONLY 2 SPECIES I.E., Oryzomys capito goeldii...

1970-01-01

123

The taxonomy of vertebrate viruses  

Microsoft Academic Search

Viruses that infect vertebrates (i.e. humans and higher animals) exhibit great diversity. They also create a variety of diseases that arise from interaction with their vertebrate hosts. This review presents the diversity of the biological and molecular properties of vertebrate viruses that aid their transmission and survival using the currently accepted taxonomic system. The Universal System of Virus Taxonomy has

Craig R. Pringle

2006-01-01

124

Endosomes, exosomes and Trojan viruses  

Microsoft Academic Search

Retroviruses are enveloped viruses that are generally assumed to bud at the plasma membrane of infected cells. Recently it has become apparent that some of these viruses use the endocytic pathway to coordinate their assembly and release. In addition, these and some other enveloped viruses exploit the machinery that generates the internal membranes of multivesicular bodies (MVB). These observations and

Annegret Pelchen-Matthews; Graça Raposo; Mark Marsh

2004-01-01

125

Virus infection improves drought tolerance  

Microsoft Academic Search

Summary • Viruses are obligate intracellular symbionts. Plant viruses are often discovered and studied as pathogenic parasites that cause diseases in agricultural plants. However, here it is shown that viruses can extend survival of their hosts under conditions of abiotic stress that could benefit hosts if they subsequently recover and reproduce.  Various plant species were inoculated with four different

Ping Xu; Fang Chen; Jonathan P. Mannas; Tracy Feldman; Lloyd W. Sumner; Marilyn J. Roossinck

2008-01-01

126

Deformed wing virus.  

PubMed

Deformed wing virus (DWV; Iflaviridae) is one of many viruses infecting honeybees and one of the most heavily investigated due to its close association with honeybee colony collapse induced by Varroadestructor. In the absence of V.destructor DWV infection does not result in visible symptoms or any apparent negative impact on host fitness. However, for reasons that are still not fully understood, the transmission of DWV by V.destructor to the developing pupae causes clinical symptoms, including pupal death and adult bees emerging with deformed wings, a bloated, shortened abdomen and discolouration. These bees are not viable and die soon after emergence. In this review we will summarize the historical and recent data on DWV and its relatives, covering the genetics, pathobiology, and transmission of this important viral honeybee pathogen, and discuss these within the wider theoretical concepts relating to the genetic variability and population structure of RNA viruses, the evolution of virulence and the development of disease symptoms. PMID:19909976

de Miranda, Joachim R; Genersch, Elke

2009-11-11

127

Ecology of prokaryotic viruses.  

PubMed

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

Weinbauer, Markus G

2004-05-01

128

Herpes Virus Amplicon Vectors  

PubMed Central

Since its emergence onto the gene therapy scene nearly 25 years ago, the replication-defective Herpes Simplex Virus Type-1 (HSV-1) amplicon has gained significance as a versatile gene transfer platform due to its extensive transgene capacity, widespread cellular tropism, minimal immunogenicity, and its amenability to genetic manipulation. Herein, we detail the recent advances made with respect to the design of the HSV amplicon, its numerous in vitro and in vivo applications, and the current impediments this virus-based gene transfer platform faces as it navigates a challenging path towards future clinical testing.

de Silva, Suresh; Bowers, William J.

2009-01-01

129

Rice Yellow Mottle Virus, an RNA Plant Virus, Evolves as Rapidly as Most RNA Animal Viruses  

Microsoft Academic Search

The rate of evolution of an RNA plant virus has never been estimated using temporally spaced sequence data, by contrast to the information available on an increasing range of animal viruses. Accordingly, the evolution rate of Rice yellow mottle virus (RYMV) was calculated from sequences of the coat protein gene of isolates collected from rice over a 40-year period in

D. Fargette; A. Pinel; M. Rakotomalala; E. Sangu; O. Traore ´; D. Sereme ´; F. Sorho; S. Issaka; E. Hebrard; Y. Sere; Z. Kanyeka; G. Konate

2008-01-01

130

Human immunodeficiency virus nephropathy  

Microsoft Academic Search

Varying components of the syndrome of human immunodeficiency virus nephropathy (HIVN) have been described, the most pertinent including proteinuria\\/nephrotic syndrome, progressive azotemia, normal blood pressure, enlarged and hyperechoic kidneys, rapid progression to end-stage renal disease (ESRD), and no response to treatment regimens. The diagnosis of HIVN requires identification of excessive proteinuria or albuminuria, determined by a total protein excretion on

Jose Strauss; Gaston Zilleruelo; Carolyn Abitbol; Brenda Montane; Victoriano Pardo

1993-01-01

131

From Shakespeare to Viruses  

ScienceCinema

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

132

Wineberry latent virus  

Technology Transfer Automated Retrieval System (TEKTRAN)

Wineberry latent virus (WLV) was discovered in a single symptomless plant of wineberry, Rubus phoenicolasius, which was growing in an experimental planting in Scotland. The plant originated in the United States, where wineberry is established in the wild in the Northeast. Experimentally, WLV can be ...

133

Yaba Virus Tumors.  

National Technical Information Service (NTIS)

The salient features of the Yaba tumor are that a DNA virus, probably a member of the pox group, produces characteristic subcutaneous growths on the face and distal portions of the limbs in some, but not all, species of nonhuman primates and in man. Tumor...

E. E. McConnell

1969-01-01

134

Blueberry shock virus  

Technology Transfer Automated Retrieval System (TEKTRAN)

Blueberry shock disease first observed in Washington state in 1987 and initially confused with blueberry scorch caused by Blueberry scorch virus (BlScV). However, shock affected plants produced a second flush of leaves after flowering and the plants appeared normal by late summer except for the lac...

135

Viruses and autophagy  

PubMed Central

SUMMARY Autophagy is an evolutionarily conserved intracellular process by which bulk cytoplasm is enveloped inside a double-membraned vesicle and shuttled to lysosomes for degradation. Within the last 15 years, the genes necessary for the execution of autophagy have been identified and the number of tools for studying this process has grown. Autophagy is essential for tissue homeostasis and development and defective autophagy is associated with a number of diseases. As intracellular parasites, during the course of an infection, viruses encounter autophagy and interact with the proteins that execute this process. Autophagy and/or autophagy genes likely play both anti-viral and proviral roles in the life cycles and pathogenesis of many different virus families. With respect to anti-viral roles, the autophagy proteins function in targeting viral components or virions for lysosomal degradation in a process termed xenophagy, and they also play a role in the initiation of innate and adaptive immune system responses to viral infections. Consistent with this anti-viral role of host autophagy, some viruses encode virulence factors that interact with the host autophagy machinery and block the execution of autophagy. In contrast, other viruses appear to utilise components of the autophagic machinery to foster their own intracellular growth or non-lytic cellular egress. As the details of the role(s) of autophagy in viral pathogenesis become clearer, new anti-viral therapies could be developed to inhibit the beneficial and enhance the destructive aspects of autophagy on the viral life cycle.

Kudchodkar, Sagar B.; Levine, Beth

2010-01-01

136

Algal Virus: Isolation  

Microsoft Academic Search

Freshwater blue-green algae of the genera Lyngbya, Plectonema, and Phormidium are susceptible to a virus recently isolated from a waste-stabilization pond. Electron micrographs of a partially purified preparation show that the viral particle has an icosahedral structure about 66 mmu in diameter.

Robert S. Safferman; Mary-Ellen Morris

1963-01-01

137

VIRUS PERSISTENCE IN GROUNDWATER  

EPA Science Inventory

The purpose of the study was to determine whether measurable chemical and physical factors correlate with virus survival in groundwater. Groundwater samples were obtained from 11 sites throughout the United States. Water temperature was measured at the time of collection. Several...

138

Evolution of infectious salmon anaemia virus (ISA virus).  

PubMed

Infectious salmon anaemia virus, ISA virus (genus Isavirus, family Orthomyxoviridae), emerged in Norwegian salmon culture in the mid-80s. The genome consists of eight segments coding for at least 10 proteins. ISA viruses show many of similarities to influenza A viruses but differ in many important aspects such as the number of hosts, the host population structure and the route of transmission. The only known hosts and reservoirs for ISA viruses are salmonids found in countries surrounding the North Atlantic. In this study, four different segments of the genome of about 100 ISA viruses have been sequenced in an attempt to understand the evolution of ISA viruses and how these viruses are maintained in and transmitted between populations of farmed Atlantic salmon. The four gene segments code for the nucleoprotein (NP), the putative acid polymerase (PA), the fusion protein (F) and the haemagglutinin-esterase (HE). Analysis of these four genes showed that the substitution rates of the internal proteins (NP and PA) are lower than those of the two surface proteins (F and HE). All four segments are evolving at a lower rate than similar genes in influenza A viruses. The ISA virus populations consist of avirulent viruses and pathogenic strains with variable virulence in Atlantic salmon. Recombination resulting in inserts close to the proteolytic-cleavage site of the precursor F0 protein and deletions in the stalk region of the HE protein seem to be responsible for the transition from avirulent ISA viruses to pathogenic strains. It is also shown that reassortment is a frequent event among the dominating ISA viruses in farmed Atlantic salmon. The pattern that is obtained after phylogenetic analysis of the four gene segments from ISA viruses suggests that the variation is limited to a few distinct clades and that no major changes have occurred in the ISA virus population in Norway since the first viruses were isolated. Calculation of the time of most recent common ancestor (TMRCA) suggests that the Norwegian ISA viruses separated from the European subtype found in North America between 1932 and 1959. The TMRCA data also suggest that the ISA viruses in Chile were transmitted from Norway in the period from 1995 to 2007, depending on which of the four genes were used in the analysis. PMID:22886279

Plarre, Heidrun; Nylund, Are; Karlsen, Marius; Brevik, Øyvind; Sæther, Per Anton; Vike, Siri

2012-08-12

139

Molecular epidemiology of respiratory viruses in virus-induced asthma  

PubMed Central

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

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

2013-01-01

140

Infectious Enveloped RNA Virus Antigenic Chimeras  

Microsoft Academic Search

Random insertion mutagenesis has been used to construct infectious Sindbis virus structural protein chimeras containing a neutralization epitope from a heterologous virus, Rift Valley fever virus. Insertion sites, permissive for recovery of chimeric viruses with growth properties similar to the parental virus, were found in the virion E2 glycoprotein and the secreted E3 glycoprotein. For the E2 chimeras, the epitope

Steven D. London; Alan L. Schmaljohn; Joel M. Dalrymple; Charles M. Rice

1992-01-01

141

Heparan Sulfate-Mediated Binding of Infectious Dengue Virus Type 2 and Yellow Fever Virus  

Microsoft Academic Search

Dengue virus type 2 and Yellow fever virus are arthropod-borne flaviviruses causing hemorrhagic fever in humans. Identification of virus receptors is important in understanding flavivirus pathogenesis. The aim of this work was to study the role of cellular heparan sulfate in the adsorption of infectious Yellow fever and Dengue type 2 viruses. Virus attachment was assessed by adsorbing virus to

Raphaële Germi; Jean-Marc Crance; Daniel Garin; Josette Guimet; Hugues Lortat-Jacob; Rob W. H. Ruigrok; Jean-Pierre Zarski; Emmanuel Drouet

2002-01-01

142

Hepatitis C Virus and other Flaviviridae Viruses Enter Cells via Low Density Lipoprotein Receptor  

Microsoft Academic Search

Endocytosis of the Flaviviridae viruses, hepatitis C virus, GB virus C\\/hepatitis G virus, and bovine viral diarrheal virus (BVDV) was shown to be mediated by low density lipoprotein (LDL) receptors on cultured cells by several lines of evidence: by the demonstration that endocytosis of these virus correlated with LDL receptor activity, by complete inhibition of detectable endocytosis by anti-LDL receptor

Vincent Agnello; Gyorgy Abel; Mutasim Elfahal; Glenn B. Knight; Qing-Xiu Zhang

1999-01-01

143

Vesicular Stomatitis Virus glycoprotein G carrying a tandem dimer of Foot and Mouth Disease Virus antigenic site A can be used as DNA and peptide vaccine for cattle.  

PubMed

Effective Foot and Mouth Disease Virus (FMDV) peptide vaccines for cattle have two major constraints: resemblance of one or more of the multiple conformations of the major VP1 antigenic sites to induce neutralizing antibodies, and stimulation of T cells despite the variable bovine-MHC polymorphism. To overcome these limitations, a chimeric antigen was developed, using Vesicular Stomatitis Virus glycoprotein (VSV-G) as carrier protein of an in tandem-dimer of FMDV antigenic site A (ASA), the major epitope on the VP1 capsid protein (aa 139-149, FMDV-C3 serotype). The G-ASA construct was expressed in the Baculovirus system to produce a recombinant protein (DEL BAC) (cloned in pCDNA 3.1 plasmid) (Invitrogen Corporation, Carlsbad, CA) and was also prepared as a DNA vaccine (pC DEL). Calves vaccinated with both immunogens elicited antibodies that recognized the ASA in whole virion and were able to neutralize FMDV infectivity in vitro. After two vaccine doses, DEL BAC induced serum neutralizing titers compatible with an "expected percentage of protection" above 90%. Plasmid pC DEL stimulated FMDV specific humoral responses earlier than DEL BAC, though IgG1 to IgG2 ratios were lower than those induced by both DEL BAC and inactivated FMDV-C3 after the second dose. DEL BAC induced FMDV-specific secretion of IFN-? in peripheral blood mononuclear cells of outbred cattle immunized with commercial FMDV vaccine, suggesting its capacity to recall anamnestic responses mediated by functional T cell epitopes. The results show that exposing FMDV-VP1 major neutralizing antigenic site in the context of N-terminal sequences of the VSV G protein can overcome the immunological limitations of FMDV-VP1 peptides as effective protein and DNA vaccines for cattle. PMID:21889542

Capozzo, Alejandra V; Wilda, Maximiliano; Bucafusco, Danilo; de los Ángeles Lavoria, María; Franco-Mahecha, Olga L; Mansilla, Florencia C; Pérez-Filgueira, Daniel M; Grigera, Pablo R

2011-08-26

144

Single virus genomics: a new tool for virus discovery.  

PubMed

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

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

2011-03-23

145

Virus entry mediated by hepatitis B virus envelope proteins  

PubMed Central

Hepatitis B virus (HBV), a major cause of human liver disease worldwide, encodes three envelope proteins needed for the attachment and entry of the virus into susceptible host cells. A second virus, hepatitis delta virus, which is known to enhance liver disease in HBV infected patients, diverts the same HBV envelope proteins to achieve its own assembly and infection. In the lab, lentiviral vectors based on human immunodeficiency virus type 1 can be assembled using the HBV envelope proteins, and will similarly infect susceptible cells. This article provides a partial review and some personal reflections of how these three viruses infect and of how recipient cells become susceptible, along with some consideration of questions that remain to be answered.

Taylor, John M

2013-01-01

146

Molecular characterization and experimental host range of an isolate of Wissadula golden mosaic St. Thomas virus.  

PubMed

Partial genome segments of a begomovirus were previously amplified from Wissadula amplissima exhibiting yellow-mosaic and leaf-curl symptoms in the parish of St. Thomas, Jamaica and this isolate assigned to a tentative begomovirus species, Wissadula golden mosaic St. Thomas virus. To clone the complete genome of this isolate of Wissadula golden mosaic St. Thomas virus, abutting primers were designed to PCR amplify its full-length DNA-A and DNA-B components. Sequence analysis of the complete begomovirus genome obtained, confirmed that it belongs to a distinct begomovirus species and this isolate was named Wissadula golden mosaic St. Thomas virus-[Jamaica:Albion:2005] (WGMSTV-[JM:Alb:05]). The genome of WGMSTV-[JM:Alb:05] is organized similar to that of other bipartite Western Hemisphere begomoviruses. Phylogenetic analyses placed the genome components of WGMSTV-[JM:Alb:05] in the Abutilon mosaic virus clade and showed that the DNA-A component is most closely related to four begomovirus species from Cuba, Tobacco leaf curl Cuba virus, Tobacco leaf rugose virus, Tobacco mottle leaf curl virus, and Tomato yellow distortion leaf virus. The putative Rep-binding-site motif in the common region of WGMSTV-[JM:Alb:05] was observed to be identical to that of Chino del tomate virus-Tomato [Mexico:Sinaloa:1983], Sida yellow mosaic Yucatan virus-[Mexico:Yucatan:2005], and Tomato leaf curl Sinaloa virus-[Nicaragua:Santa Lucia], suggesting that WGMSTV-[JM:Alb:05] is capable of forming viable pseudo-recombinants with these begomoviruses, but not with other members of the Abutilon mosaic virus clade. Biolistic inoculation of test plant species with partial dimers of the WGMSTV-[JM:Alb:05] DNA-A and DNA-B components showed that the virus was infectious to Nicotiana benthamiana and W. amplissima and the cultivated species Phaseolus vulgaris (kidney bean) and Lycopersicon esculentum (tomato). Infected W. amplissima plants developed symptoms similar to symptoms observed under field conditions, confirming that this virus is a causal agent of Wissadula yellow mosaic disease in W. amplissima. PMID:19768650

Collins, A M; Mujaddad-ur-Rehman, Malik; Brown, J K; Reddy, C; Wang, A; Fondong, V; Roye, M E

2009-09-20

147

Boletín del Instituto Nacional del Cáncer - 02-02-2010  

Cancer.gov

En un estudio clínico en fase inicial que probó una vacuna terapéutica en pacientes con leucemia mieloide crónica (LMC) que tomaban el fármaco imatinib (Gleevec), no se pudieron detectar células cancerosas en 7 de los 19 participantes por un tiempo promedio de 22 meses. Los resultados del estudio fueron publicados en el número del 1º de enero de la revista Clinical Cancer Research.

148

Human herpes virus 8: a new virus discloses its face  

Microsoft Academic Search

The human herpes virus 8 (HHV8) or Kaposi’s sarcoma-associated herpes virus (KSHV) is present in all Kaposi’s sarcoma, and\\u000a the detection of the virus using polymerase chain reaction or in situ hybridization is a highly sensitive and specific diagnostic\\u000a test for the diagnosis of this neoplasm. HHV8 is furthermore invariably present in primary effusion lymphoma (PEL) and has\\u000a also been

Gieri Cathomas

2000-01-01

149

Computer viruses: ways of reproduction in MS-DOS  

Microsoft Academic Search

The methods used by computer viruses to reproduce themselves in IBM PC-compatibles operating under MS-DOS are studied. The results can be of use for classification of viruses and the creation of anti-virus tools. Viruses are examined under the following headings: irritating viruses, viruses that damage files, viruses that damage the file system and viruses that injure the hardware

S. I. Shoutkov; A. V. Spesivtsev

1991-01-01

150

Competitive virus assay method for titration of noncytopathogenic bovine viral diarrhea viruses (END? and END? viruses).  

PubMed

A new, reliable and secure virus assay method, named the competitive virus assay (CVA) method, has been established for the titration of bovine viral diarrhea viruses (BVDVs) that either show the exaltation of Newcastle disease virus (END) phenomenon or heterologous interference phenomenon (but not the END phenomenon). This method is based on the principle of (1) homologous interference between BVDVs, by using BVDV RK13/E(-) or BVDV RK13/E(+) strains as competitor virus, and (2) END phenomenon and heterologous interference, by using attenuated Newcastle disease virus (NDV) TCND strain as challenge virus. In titration of BVDV END(+) and BVDV END(-) viruses, no significant difference in estimated virus titer was observed between CVA and conventional methods. CVA method demonstrated comparable levels of sensitivity and accuracy as conventional END and interference methods, which require the use of a velogenic Miyadera strain of NDV and vesicular stomatitis virus (VSV), both of which are agents of high-risk diseases. As such, the CVA method is a safer alternative, with increased bio-safety and bio-containment, through avoidance of virulent strains that are commonly employed with conventional methods. PMID:23219806

Muhsen, Mahmod; Ohi, Kota; Aoki, Hiroshi; Ikeda, Hidetoshi; Fukusho, Akio

2012-12-05

151

Making Better Influenza Virus Vaccines?  

PubMed Central

Killed and live influenza virus vaccines are effective in preventing and curbing the spread of disease, but new technologies such as reverse genetics could be used to improve them and to shorten the lengthy process of preparing vaccine seed viruses. By taking advantage of these new technologies, we could develop live vaccines that would be safe, cross-protective against variant strains, and require less virus per dose than conventional vaccines. Furthermore, pandemic vaccines against highly virulent strains such as the H5N1 virus can only be generated by reverse genetics techniques. Other technologic breakthroughs should result in effective adjuvants for use with killed and live vaccines, increasing the number of available doses. Finally, universal influenza virus vaccines seem to be within reach. These new strategies will be successful if they are supported by regulatory agencies and if a robust market for influenza virus vaccines against interpandemic and pandemic threats is made and sustained.

2006-01-01

152

Principles of Virus Structural Organization  

PubMed Central

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.

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

2013-01-01

153

Proteorhodopsin genes in giant viruses.  

PubMed

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. PMID:23036091

Yutin, Natalya; Koonin, Eugene V

2012-10-04

154

Proteorhodopsin genes in giant viruses  

PubMed Central

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.

2012-01-01

155

Cáncer de cuello del útero o uterino  

Cancer.gov

Información acerca del cáncer de cérvix (cervical o cuello uterino), lo cual incluye temas como tratamiento, prevención, causas, factores de riesgo, exámenes selectivos de detección, estudios clínicos y estadísticas del Instituto Nacional del Cáncer.

156

Acid Sensitivity of the Influenza Virus Hemagglutinin  

PubMed Central

Influenza virus hemagglutinin was shown to be acid resistant if precipitates which form during acidification are first removed. Adsorption of virus to precipitates formed during acidification may cause a virus to be described incorrectly as acid sensitive.

Henderson, Marilyn; Wallis, Craig; Melnick, Joseph L.

1973-01-01

157

West Nile Virus Infection and Pregnancy  

MedlinePLUS

... or visit us online at: www.OTISpregnancy.org . West Nile Virus Infection and Pregnancy This sheet talks about ... advice from your health care provider. What is West Nile Virus (WNV)? WNV is a virus that can ...

158

Advances in virus research. Volume 29  

SciTech Connect

This book contains nine chapters. Some of the titles are: Molecular Biology of Wound Tumor Virus; The Application of Monoclonal Antibodies in the Study of Viruses; Prions: Novel Infectious Pathogens; and Monoclonal Antibodies Against Plant Viruses.

Lauffer, M.A.; Maramorosch, K.

1984-01-01

159

The encephalomyocarditis virus  

PubMed Central

The encephalomyocarditis virus (EMCV) is a small non-enveloped single-strand RNA virus, the causative agent of not only myocarditis and encephalitis, but also neurological diseases, reproductive disorders and diabetes in many mammalian species. EMCV pathogenesis appears to be viral strain- and host-specific, and a better understanding of EMCV virulence factors is increasingly required. Indeed, EMCV is often used as a model for diabetes and viral myocarditis, and is also widely used in immunology as a double-stranded RNA stimulus in the study of Toll-like as well as cytosolic receptors. However, EMCV virulence and properties have often been neglected. Moreover, EMCV is able to infect humans albeit with a low morbidity. Progress on xenografts, such as pig heart transplantation in humans, has raised safety concerns that need to be explored. In this review we will highlight the biology of EMCV and all known and potential virulence factors.

Carocci, Margot; Bakkali-Kassimi, Labib

2012-01-01

160

Virus-encoded superantigens.  

PubMed Central

Superantigens are microbial agents that have a strong effect on the immune response of the host. Their initial target is the T lymphocyte, but a whole cascade of immunological reactions ensues. It is thought that the microbe engages the immune system of the host to its own advantage, to facilitate persistent infection and/or transmission. In this review, we discuss in detail the structure and function of the superantigen encoded by the murine mammary tumor virus, a B-type retrovirus which is the causative agent of mammary carcinoma. We will also outline what has more recently become known about superantigen activity associated with two human herpesviruses, cytomegalovirus and Epstein-Barr virus. It is likely that we have only uncovered the tip of the iceberg in our discovery of microbial superantigens, and we predict a flood of new information on this topic shortly.

Huber, B T; Hsu, P N; Sutkowski, N

1996-01-01

161

EL ORIGEN BIOLÓGICO DEL DERECHO  

Microsoft Academic Search

En este trabajo se aborda el posible origen evolutivo del derecho como una consecuencia del desarrollo social de nuestra especie. Otras especies con sistemas sociales similares presentan varias reglas para la convivencia en grupo. Algunas de estas reglas son comunes en todas las especies con comportamiento social. El desarrollo de la sociobiología en las últimas décadas es una herramienta importante

Axel P. Retana-Salazar

162

Immunopathogenesis of dengue virus infection  

Microsoft Academic Search

Dengue virus infection causes dengue fever (DF), dengue hemorrhagic fever (DHF), and dengue shock syndrome (DSS), whose pathogeneses are not clearly understood. Current hypotheses of antibody-dependent enhancement, virus virulence, and IFN-?\\/TNF?-mediated immunopathogenesis are insufficient to explain clinical manifestations of DHF\\/DSS such as thrombocytopenia and hemoconcentration. Dengue virus infection induces transient immune aberrant activation of CD4\\/CD8 ratio inversion and cytokine overproduction,

Huan-Yao Lei; Trai-Ming Yeh; Hsiao-Sheng Liu; Yee-Shin Lin; Shun-Hua Chen; Ching-Chuan Liu

2001-01-01

163

A DNA Virus of Drosophila  

Microsoft Academic Search

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

Robert L. Unckless

2011-01-01

164

Epstein-Barr Virus  

Microsoft Academic Search

Epstein-Barr virus (EBV) is a ubiquitous human herpesvirus. Infection with EBV is common, worldwide in distribution, and largely\\u000a subclinical in early childhood. EBV has been established as the causative agent of heterophile-positive mononucleosis, which\\u000a occurs most frequently in late adolescence or early adulthood. In addition, seroepidemologic data have suggested that EBV\\u000a also plays an etiological role in African Burkitt’s lymphoma

Suresh B. Boppana

165

Genus Orthopoxvirus: Cowpox virus  

Microsoft Academic Search

\\u000a Cowpox virus (CPXV) is distinguished from other orthopoxvirus (OPV) species by producing cytoplasmic A-type inclusion bodies and flattened\\u000a pocks with a hemorrhagic center on the chorioallantoic membrane. CPXV is endemic to Western Eurasia and naturally infects\\u000a a broad range of host species including domestic animals, and zoo animals, as well as humans. Infections in humans seem to\\u000a increase in importance

Sandra Essbauer; Hermann Meyer

166

Human Immunodeficiency Virus  

Microsoft Academic Search

Oral health is an integral component of overall health and well-being in all patients. However, for an immunocompromised patient,\\u000a many common oral conditions may have a significant impact on quality of life. Intraoral pain, which is a common complaint\\u000a among patients with human immunodeficiency virus (HIV), will compromise patients’ ability to maintain adequate and appropriate\\u000a oral intake. Furthermore, the polypharmacopeia

Anita Patel; Michael Glick

167

Genus Orthopoxvirus: Variola virus  

Microsoft Academic Search

Variola major virus caused the human disease smallpox; interpretations of the historic record indicate that the initial introduction\\u000a of disease in a naïve population had profound effects on its demographics. Smallpox was declared eradicated by the World Health\\u000a Organization (WHO) in 1980. This chapter reviews epidemiological, clinical and pathophysiological observations of disease,\\u000a and review some of the more recent observations

Inger K. Damon

168

Measles Virus Receptors  

Microsoft Academic Search

Measles virus (MV) has two envelope glycoproteins, the hemagglutinin (H) and fusion protein, which are responsible for attachment\\u000a and membrane fusion, respectively. Signaling lymphocyte activation molecule (SLAM, also called CD150), a membrane glycoprotein\\u000a expressed on immune cells, acts as the principal cellular receptor for MV, accounting for its lymphotropism and immunosuppressive\\u000a nature. MV also infects polarized epithelial cells via an

Y. Yanagi; M. Takeda; S. Ohno; T. Hashiguchi

169

9 CFR 113.311 - Bovine Virus Diarrhea Vaccine.  

Code of Federal Regulations, 2010 CFR

...Bovine Virus Diarrhea Vaccine. Bovine Virus Diarrhea Vaccine...follows: (1) Twenty-five bovine virus diarrhea susceptible...vaccinates and five controls). Blood samples shall be drawn from...be considered susceptible to bovine virus diarrhea virus...

2010-01-01

170

9 CFR 113.311 - Bovine Virus Diarrhea Vaccine.  

Code of Federal Regulations, 2010 CFR

...Bovine Virus Diarrhea Vaccine. Bovine Virus Diarrhea Vaccine...follows: (1) Twenty-five bovine virus diarrhea susceptible...vaccinates and five controls). Blood samples shall be drawn from...be considered susceptible to bovine virus diarrhea virus...

2009-01-01

171

Marek's disease virus morphogenesis.  

PubMed

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

Denesvre, Caroline

2013-06-01

172

West Nile Virus Maps  

NSDL National Science Digital Library

One of the potential effects of global climate change is the spread of disease to new areas, as the vectors of those diseases (e.g., mosquitoes, birds) expand into new locations in response to shifting climate conditions. Although the direct cause of West Nile Virus (WNV) in the United States is not known, the National Atlas of the US Geological Survey (reviewed in the June 26, 1998 Scout Report) has recently launched this new resource on WNV distribution. First documented in the US during the summer of 1999 and previously limited to Africa, Eastern Europe, West Asia, and the Middle East, the West Nile Virus is of danger to humans as it interferes with "normal central nervous system functioning" and can cause encephalitis. This site describes WNV Surveillance Activity for the year 2000 and offers a series of maps highlighting the US distribution of WNV cases found in humans, wild birds, chickens, mosquitoes, and veterinary clinics. A series of links point to further information on the virus.

173

Nipah Virus Infection  

PubMed Central

In 1998, an outbreak of acute encephalitis with high mortality rates among pig handlers in Malaysia led to the discovery of a novel paramyxovirus named Nipah virus. A multidisciplinary investigation that included epidemiology, microbiology, molecular biology, and pathology was pivotal in the discovery of this new human infection. Clinical and autopsy findings were derived from a series of 32 fatal human cases of Nipah virus infection. Diagnosis was established in all cases by a combination of immunohistochemistry (IHC) and serology. Routine histological stains, IHC, and electron microscopy were used to examine autopsy tissues. The main histopathological findings included a systemic vasculitis with extensive thrombosis and parenchymal necrosis, particularly in the central nervous system. Endothelial cell damage, necrosis, and syncytial giant cell formation were seen in affected vessels. Characteristic viral inclusions were seen by light and electron microscopy. IHC analysis showed widespread presence of Nipah virus antigens in endothelial and smooth muscle cells of blood vessels. Abundant viral antigens were also seen in various parenchymal cells, particularly in neurons. Infection of endothelial cells and neurons as well as vasculitis and thrombosis seem to be critical to the pathogenesis of this new human disease.

Wong, Kum Thong; Shieh, Wun-Ju; Kumar, Shalini; Norain, Karim; Abdullah, Wahidah; Guarner, Jeannette; Goldsmith, Cynthia S.; Chua, Kaw Bing; Lam, Sai Kit; Tan, Chong Tin; Goh, Khean Jin; Chong, Heng Thay; Jusoh, Rani; Rollin, Pierre E.; Ksiazek, Thomas G.; Zaki, Sherif R.

2002-01-01

174

Structure of Flexible Filamentous Plant Viruses  

SciTech Connect

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.

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 (IIT); (BU-M); (Vanderbilt); (Kentucky); (BNL)

2008-10-23

175

Computer virus information update CIAC-2301  

SciTech Connect

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.

Orvis, W.J.

1994-01-15

176

Structure of Flexible Filamentous Plant Viruses ?  

PubMed Central

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.

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

2008-01-01

177

Physicochemical Properties of Tipula Iridescent Virus 1  

PubMed Central

The molecular weight of Tipula iridescent virus, based on sedimentation and diffusion coefficients, was 5.51 × 108, with hydration of 0.57 g of water per g of virus. Deoxyribonucleic acid content, based on total inorganic phosphorus liberated, was 19 ± 0.2%. At 260 m?, the virus gave an uncorrected absorbance of 18.2 cm2/mg of virus and a light-scattering corrected absorbance of 9.8 cm2/mg of virus. Amino acid analyses of the virus protein revealed a remarkable similarity to Sericesthis iridescent virus. The possibility is discussed that the four iridescent insect viruses reported to date bear a strain relationship. Images

Kalmakoff, J.; Tremaine, J. H.

1968-01-01

178

Genome of crocodilepox virus.  

PubMed

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 the unique nature of CRV and suggest mechanisms of virus-reptile host interaction. PMID:16641289

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

179

Magnetic Fluorescent Composite Nanoparticles for the Fluoroimmunoassays of Newcastle Disease Virus and Avian Virus Arthritis Virus  

Microsoft Academic Search

A new detection format for multiplexed analysis based on the use of magnetic fluorescent composite nanoparticles was presented\\u000a in this paper. Two different antigens, Newcastle disease virus (NDV) antigen and Avian virus arthritis virus (AVAV) antigen,\\u000a were conjugated to two kinds of magnetic fluorescent composite nanoparticles of different luminescent colors, while red-emitting\\u000a CdTe QDs were attached to the antibody of

Guannan Wang; Ping Xie; Chengrui Xiao; Pingfan Yuan; Xingguang Su

2010-01-01

180

DETECTION OF RETICULOENDOTHELIOSIS VIRUS IN LIVE VIRUS VACCINES OF POULTRY  

Technology Transfer Automated Retrieval System (TEKTRAN)

Reticuloendotheliosis virus (REV) is an avian oncornavirus that is structurally and antigenically unrelated to the leukosis-sarcoma group of viruses. All REV isolates are antigenically related to each other. However, using monoclonal antibodies, REV isolates can be classed into three different subty...

181

Peptide inhibitors of dengue virus and West Nile virus infectivity  

Microsoft Academic Search

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

Yancey M Hrobowski; Robert F Garry; Scott F Michael

2005-01-01

182

Electron microscopy of viruses and virus-cell interactions.  

PubMed

Electron microscopy is a powerful tool to visualize viruses in diagnostic as well as in research settings for investigating viral structure and virus-cell interactions. Here, a simple but efficient method is described for demonstrating viruses by negative staining, and its limit is discussed. A prerequisite to obtain reliable information on virus-cell interactions is excellent preservation of cellular and viral ultrastructure. The crux is that during fixation and embedding, by applying conventional protocols about 50% of the lipids are lost, which results in loss of integrity of cell membranes. To achieve good preservation of cellular architectures, good contrast, and both high spatial and temporal resolution, methods for freezing, freeze-substitution, and freeze-etching are described and their applicability discussed mostly taking complicated built herpes viruses as examples. PMID:18617049

Wild, Peter

2008-01-01

183

Characterization of infectious bursal disease viruses isolated in 2007 from Delmarva commercial broiler chickens.  

PubMed

A study was performed in 2007 to isolate and characterize infectious bursal disease viruses (IBDVs) in commercial broilers grown in the Delmarva (DMV) Peninsula region of the United States. Bursae of Fabricius were collected weekly from 1 to 4 wk of age from broilers on 10 farms with a history of poor performance. Microscopic pathology was used to determine the infectious bursal disease (IBD) status of the broilers. Bursae from 1- and 2-wk-old broilers did not show IBD microscopic lesions. Moreover, broilers on 1 of the 10 farms were IBD lesion free at 3 and 4 wk of age. However, 3 of 9 and 9 of 9 farms yielded broilers with IBD-affected bursae from 3- and 4-wk-old commercial broilers, respectively. Ten IBDV isolates were recovered from 3 of 3 lesion-positive bursal pools at 3 wk of age and 7 of 9 lesion-positive bursal pools at 4 wk of age. Analysis of the viral protein (VP) 2 genes identified all isolates as serotype 1 Delaware (Del) variant viruses. Five field isolates, each representing different molecular clades of the Delaware variant viruses, were selected for further study. Experimental infection of specific-pathogen-free white leghorn chickens with isolates DMV/4813/07, DMV/4947/07, DMV/4955/07, DMV/5038/07, and DMV/5041/07 produced gross and microscopic pathology of the bursa consistent with Delaware variant infection. Monoclonal antibody testing showed DMV/4813/07, DMV/4947/07, DMV/ 4955/07, and DMV/5041/07 to be similar to previous recognized variant viruses. However, DMV/5038/07 was found to be unreactive with the monoclonal antibodies that typically recognize reference strains STC, Del E, GLS, RS593, and AL2. In a challenge of immunity study, 10-day-old progeny from breeders immunized with a commercially available inactivated IBDV vaccine containing the Del E and classic strains were protected to a lesser degree against isolate DMV/5038/07 compared to Del E challenge based on microscopic lesion scores (P < 0.01) of the bursa. This result suggests the virus is antigenically different from the Del E strain contained in the vaccine. Collectively, the monoclonal antibody and progeny challenge of immunity findings suggest DMV/5038/07 is antigenically different from the Del E strain contained in the vaccine. PMID:22545532

Gelb, J; Jackwood, D J; Mundt, E; Pope, C R; Hein, R; Slacum, G; Harris, J M; Ladman, B S; Lynch, P; Bautista, D A; Ruano, J M; Troeber, M M

2012-03-01

184

Prevalence and transmission of honeybee viruses.  

PubMed

Transmission mechanisms of six honeybee viruses, including acute bee paralysis virus (ABPV), black queen cell virus (BQCV), chronic bee paralysis virus (CBPV), deformed wing virus (DWV), Kashmir bee virus (KBV), and sacbrood bee virus (SBV), in honey bee colonies were investigated by reverse transcription-PCR (RT-PCR) methods. The virus status of individual queens was evaluated by examining the presence of viruses in the queens' feces and tissues, including hemolymph, gut, ovaries, spermatheca, head, and eviscerated body. Except for head tissue, all five tissues as well as queen feces were found to be positive for virus infections. When queens in bee colonies were identified as positive for BQCV, DWV, CBPV, KBV, and SBV, the same viruses were detected in their offspring, including eggs, larvae, and adult workers. On the other hand, when queens were found positive for only two viruses, BQCV and DWV, only these two viruses were detected in their offspring. The presence of viruses in the tissue of ovaries and the detection of the same viruses in queens' eggs and young larvae suggest vertical transmission of viruses from queens to offspring. To our knowledge, this is the first evidence of vertical transmission of viruses in honeybee colonies. PMID:16391097

Chen, Y P; Pettis, J S; Collins, A; Feldlaufer, M F

2006-01-01

185

INFECTIOUS DOSE OF NORWALK VIRUS  

EPA Science Inventory

The Norwalk virus and related viruses (caliciviruses) have been identified as a common cause of waterborne disease. Moreover, there are many outbreaks of waterborne disease every year where the causative agent was never identified, and it is thought that many of these are due to ...

186

Antivirals for High Hazard Viruses,  

National Technical Information Service (NTIS)

In large areas of the world there exist extremely high hazard viruses for which there are no vaccines for prophylaxis and no effective drugs for therapy. Examples of such viruses are Ebola, Argentine, Bolivian, Crimean-Congo, and Korean hemorrhagic fevers...

P. G. Canonico

1988-01-01

187

Influenza Virus Assembly and Budding  

PubMed Central

Influenza A virus causes seasonal epidemics, sporadic pandemics and is a significant global heath burden. Influenza virus is an enveloped virus that contains a segmented negative strand RNA genome. Assembly and budding of progeny influenza virions is a complex, multistep process that occurs in lipid raft domains on the apical membrane of infected cells. The viral proteins hemagglutinin (HA) and neuraminidase (NA) are targeted to lipid rafts, causing the coalescence and enlargement of the raft domains. This clustering of HA and NA may cause a deformation of the membrane and the initiation of the virus budding event. M1 is then thought to bind to the cytoplasmic tails of HA and NA where it can then polymerize and form the interior structure of the emerging virion. M1, bound to the cytoplasmic tails of HA and NA, additionally serves as a docking site for the recruitment of the viral RNPs and may mediate the recruitment of M2 to the site of virus budding. M2 initially stabilizes the site of budding, possibly enabling the polymerization of the matrix protein and the formation of filamentous virions. Subsequently, M2 is able to alter membrane curvature at the neck of the budding virus, causing membrane scission and the release of the progeny virion. This review investigates the latest research on influenza virus budding in an attempt to provide a step-by-step analysis of the assembly and budding processes for influenza viruses.

Rossman, Jeremy S.; Lamb, Robert A.

2011-01-01

188

Preventing zoonotic influenza virus infection.  

PubMed

We evaluated 49 swine industry workers and 79 nonexposed controls for antibodies to swine influenza viruses. Multivariate modeling showed that workers who seldom used gloves (odds ratio [OR] 30.3) or who smoked (OR 18.7) most frequently had evidence of previous H1N1 swine virus. These findings may be valuable in planning for pandemic influenza. PMID:16707061

Ramirez, Alejandro; Capuano, Ana W; Wellman, Debbie A; Lesher, Kelly A; Setterquist, Sharon F; Gray, Gregory C

2006-06-01

189

VIRUS TRANSPORT IN THE SUBSURFACE  

EPA Science Inventory

The importance of virus transport in the subsurface is highlighted by implications to human health as well as drinking water regulations. The structure of virus particles is defined along with their colloidal physiochemical properties and a discussion of their more prominent sou...

190

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...

191

West Nile Virus and Wildlife  

Microsoft Academic Search

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,

Peter P. Marra; Sean Griffing; Carolee Caffrey; A. Marm Kilpatrick; Robert McLean; Christopher Brand; Emi Saito; Alan P. Dupuis; Laura Kramer; Robert Novak

2004-01-01

192

Cassava virus diseases in Africa  

Microsoft Academic Search

Cassava plays a key role in the food security of sub-Saharan Africa, but as a vegetatively propagated crop, it is particularly vulnerable to the effects of virus diseases and these therefore represent a major threat to the livelihoods of millions of Africans. Nine viruses have been isolated from African cassava, but only cassava mosaic geminiviruses (CMGs) and Cassava brown streak

J. M. Threshb

193

Cassava virus diseases in Africa  

Microsoft Academic Search

Abstract Cassava plays a key role in the food security of sub-Saharan Africa, but as a vegetatively propagated crop, it is particularly vulnerable to the effects of virus diseases and these therefore represent a major,threat to the livelihoods of millions of Africans. Nine viruses have been isolated from African cassava, but only cassava mosaic geminiviruses (CMGs) and Cassava brown streak

J. p. Legg; J. m. Thresh

194

Human viruses: discovery and emergence  

PubMed Central

There are 219 virus species that are known to be able to infect humans. The first of these to be discovered was yellow fever virus in 1901, and three to four new species are still being found every year. Extrapolation of the discovery curve suggests that there is still a substantial pool of undiscovered human virus species, although an apparent slow-down in the rate of discovery of species from different families may indicate bounds to the potential range of diversity. More than two-thirds of human viruses can also infect non-human hosts, mainly mammals, and sometimes birds. Many specialist human viruses also have mammalian or avian origins. Indeed, a substantial proportion of mammalian viruses may be capable of crossing the species barrier into humans, although only around half of these are capable of being transmitted by humans and around half again of transmitting well enough to cause major outbreaks. A few possible predictors of species jumps can be identified, including the use of phylogenetically conserved cell receptors. It seems almost inevitable that new human viruses will continue to emerge, mainly from other mammals and birds, for the foreseeable future. For this reason, an effective global surveillance system for novel viruses is needed.

Woolhouse, Mark; Scott, Fiona; Hudson, Zoe; Howey, Richard; Chase-Topping, Margo

2012-01-01

195

Genetic Diversity of Toscana Virus  

PubMed Central

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).

Collao, Ximena; Palacios, Gustavo; Sanbonmatsu-Gamez, Sara; Perez-Ruiz, Mercedes; Negredo, Ana I.; Navarro-Mari, Jose-Maria; Grandadam, Marc; Aransay, Ana Maria; Lipkin, W. Ian; Tenorio, Antonio

2009-01-01

196

Virus-derived transgenes expressing hairpin RNA give immunity to Tobacco mosaic virus and Cucumber mosaic virus  

Microsoft Academic Search

BACKGROUND: An effective method for obtaining resistant transgenic plants is to induce RNA silencing by expressing virus-derived dsRNA in plants and this method has been successfully implemented for the generation of different plant lines resistant to many plant viruses. RESULTS: Inverted repeats of the partial Tobacco mosaic virus (TMV) movement protein (MP) gene and the partial Cucumber mosaic virus (CMV)

Qiong Hu; Yanbing Niu; Kai Zhang; Yong Liu; Xueping Zhou

2011-01-01

197

New aspects of influenza viruses.  

PubMed Central

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.

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

1992-01-01

198

Marine Viruses: Truth or Dare  

NASA Astrophysics Data System (ADS)

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.

Breitbart, Mya

2012-01-01

199

EPSTEIN-BARR VIRUS  

PubMed Central

Epstein-Barr virus (EBV)-transformed autologous lymphoblasts were repeatedly inoculated into three squirrel monkeys. Each animal developed the heterophile antibodies of infectious mononucleosis and EBV-specific antibodies. After serologic responses had disappeared or markedly declined, the animals were challenged with either whole cells, cell filtrate, or cell ghosts. Animals challenged with living cells and cell ghosts developed agglutinin responses; the recipient of filtrate did not. The results suggest that EBV induces the appearance of the infectious mononucleosis heterophile antigen on the transformed cell membrane.

Shope, Thomas; Miller, George

1973-01-01

200

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

PubMed Central

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.

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

201

Pathogenicity and immunogenicity of influenza viruses with genes from the 1918 pandemic virus  

Microsoft Academic Search

The 1918 influenza A H1N1 virus caused the worst pandemic of influenza ever recorded. To better understand the pathogenesis and immunity to the 1918 pandemic virus, we generated recombinant influenza viruses possessing two to five genes of the 1918 influenza virus. Recombinant influenza viruses possessing the hemagglutinin (HA), neuraminidase (NA), matrix (M), nonstructural (NS), and nucleoprotein (NP) genes or any

Terrence M. Tumpey; Adolfo García-Sastre; Jeffery K. Taubenberger; Peter Palese; David E. Swayne; Christopher F. Basler

2004-01-01

202

A Seven-Segmented Influenza A Virus Expressing the Influenza C Virus Glycoprotein HEF  

Microsoft Academic Search

Influenza viruses are classified into three types: A, B, and C. The genomes of A- and B-type influenza viruses consist of eight RNA segments, whereas influenza C viruses only have seven RNAs. Both A and B influenza viruses contain two major surface glycoproteins: the hemagglutinin (HA) and the neuraminidase (NA). Influenza C viruses have only one major surface glycoprotein, HEF

Qinshan Gao; Edward W. A. Brydon; Peter Palese

2008-01-01

203

Infectious vaccinia virus recombinants that express hepatitis B virus surface antigen  

NASA Astrophysics Data System (ADS)

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.

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

1983-04-01

204

STRAWBERRY NECROTIC SHOCK VIRUS: A NEW VIRUS PREVIOUSLY THOUGHT TO BE TOBACCO STREAK VIRUS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Tobacco streak virus (TSV) has a wide host range that exceeds 80 species (Fulton, 1948). Most of the efforts carried out previously comparing TSV isolates was based on immunological relations between them. The isolates of the virus from Fragaria and Rubus have been considered very closely related, ...

205

The Acute bee paralysis virus-Kashmir bee virus-Israeli acute paralysis virus complex.  

PubMed

Acute bee paralysis virus (ABPV), Kashmir bee virus (KBV) and Israeli acute paralysis virus (IAPV) are part of a complex of closely related viruses from the Family Dicistroviridae. These viruses have a widespread prevalence in honey bee (Apis mellifera) colonies and a predominantly sub-clinical etiology that contrasts sharply with the extremely virulent pathology encountered at elevated titres, either artificially induced or encountered naturally. These viruses are frequently implicated in honey bee colony losses, especially when the colonies are infested with the parasitic mite Varroa destructor. Here we review the historical and recent literature of this virus complex, covering history and origins; the geographic, host and tissue distribution; pathology and transmission; genetics and variation; diagnostics, and discuss these within the context of the molecular and biological similarities and differences between the viruses. We also briefly discuss three recent developments relating specifically to IAPV, concerning its association with Colony Collapse Disorder, treatment of IAPV infection with siRNA and possible honey bee resistance to IAPV. PMID:19909972

de Miranda, Joachim R; Cordoni, Guido; Budge, Giles

2009-11-11

206

Immunogenicity of combination DNA vaccines for Rift Valley fever virus, tick-borne encephalitis virus, Hantaan virus, and Crimean Congo hemorrhagic fever virus  

Microsoft Academic Search

DNA vaccines for Rift Valley fever virus (RVFV), Crimean Congo hemorrhagic fever virus (CCHFV), tick-borne encephalitis virus (TBEV), and Hantaan virus (HTNV), were tested in mice alone or in various combinations. The bunyavirus vaccines (RVFV, CCHFV, and HTNV) expressed Gn and Gc genes, and the flavivirus vaccine (TBEV) expressed the preM and E genes. All vaccines were delivered by gene

Kristin Spik; Amy Shurtleff; Anita K. McElroy; Mary C. Guttieri; Jay W. Hooper; Connie Schmaljohn

2006-01-01

207

Pheasant Virus: New Class of Ribodeoxyvirus  

Microsoft Academic Search

Cocultivation of cells derived from embryos of golden pheasants or Amherst pheasants with chicken embryo cells infected with Bryan strain of Rous sarcoma virus resulted in the detection of viruses which appear to be endogenous in these pheasant cells. The pheasant viruses (PV) were similar to avian leukosis-sarcoma viruses (ALSV) in their gross morphology, in the size of their RNA,

T. Hanafusa; H. Hanafusa; C. E. Metroka; W. S. Hayward; C. W. Rettenmier; R. C. Sawyer; R. M. Dougherty; H. S. Distefano

1976-01-01

208

Biologically Inspired Defenses Against Computer Viruses  

Microsoft Academic Search

Today's anti-virus technology, based largely on analysis of existing viruses by human experts, is just barely able to keep pace with the more than three new computer viruses that are writ­ ten daily. In a few years, intelligent agents nav­ igating through highly connected networks are likely to form an extremely fertile medium for a new breed of viruses. At

Jeffrey O. Kephart; Gregory B. Sorkin; William C. Arnold; David M. Chess; Gerald Tesauro; Steve R. White

1995-01-01

209

Ebola Virus Antibodies in Fruit Bats, Bangladesh  

PubMed Central

To determine geographic range for Ebola virus, we tested 276 bats in Bangladesh. Five (3.5%) bats were positive for antibodies against Ebola Zaire and Reston viruses; no virus was detected by PCR. These bats might be a reservoir for Ebola or Ebola-like viruses, and extend the range of filoviruses to mainland Asia.

Islam, Ariful; Yu, Meng; Anthony, Simon J.; Epstein, Jonathan H.; Khan, Shahneaz Ali; Khan, Salah Uddin; Crameri, Gary; Wang, Lin-Fa; Lipkin, W. Ian; Luby, Stephen P.; Daszak, Peter

2013-01-01

210

Polyoma Virus: Production in Bacillus subtilis  

Microsoft Academic Search

Particles of complete polyoma virus are produced in competent Bacillus subtilis incubated with DNA isolated from purified, conventionally grown polyoma virus. The virus grown in B. subtilis is biologically identical to polyoma virus produced by animal cells. Quantitative parameters of the system have been established, and fluctuation tests indicate that viral replication occurs within the infected bacteria.

K. E. Bayreuther; W. R. Romig

1964-01-01

211

Taxonomic Classification of Human Hepatitis B Virus  

Microsoft Academic Search

Summary Sufficient data have accumulated to permit the ICTV Study Group on the Nomenclature of Hepatitis Viruses to recognize human hepatitis B virus as a member of a unique group of viruses and to classify it, together with a number of related animal viruses, into a new family called the Hepadnaviridae. Over the past decade, the International Committee on Taxonomy

Ian D. Gust; Christopher J. Burrell; Anthony G. Coulepis; William S. Robinson; Arie J. Zuckerman

1986-01-01

212

Analysis of Complete Puumala Virus Genome, Finland  

PubMed Central

Puumala virus causes nephropathia epidemica, a rodent-borne zoonosis that is endemic to Europe. We sequenced the complete Puumala virus genome that was directly recovered from a person who died and compared it with those of viruses from local bank voles. The virus strain involved was neither a unique nor rare genetic variant.

Plyusnina, Angelina; Razzauti, Maria; Sironen, Tarja; Niemimaa, Jukka; Vapalahti, Olli; Vaheri, Antti; Henttonen, Heikki

2012-01-01

213

Analysis of complete Puumala virus genome, Finland.  

PubMed

Puumala virus causes nephropathia epidemica, a rodent-borne zoonosis that is endemic to Europe. We sequenced the complete Puumala virus genome that was directly recovered from a person who died and compared it with those of viruses from local bank voles. The virus strain involved was neither a unique nor rare genetic variant. PMID:23171600

Plyusnina, Angelina; Razzauti, Maria; Sironen, Tarja; Niemimaa, Jukka; Vapalahti, Olli; Vaheri, Antti; Henttonen, Heikki; Plyusnin, Alexander

2012-12-01

214

Interference Between the Vaccinal Virus and the Common Rabies Virus (Interference Entre le Virus Vaccinal et le Virus Rabique des Rues).  

National Technical Information Service (NTIS)

An interference between the vaccinal virus and the virus of rabies has been demonstrated using the rabbit. The method of inoculation for the vaccinal virus as well as for the rabies virus was the intradermal method and this method allowed the demonstratio...

J. Vieuchange M. A. Chabaud C. Vialat

1969-01-01

215

Alberto del Pozo  

NSDL National Science Digital Library

The Cuban Heritage Collection of the University of Miami Libraries was a recipient of 17 original illustrations by Alberto del Pozo in 1998 from the Campilli family. "The Oricha Collection" is their gift, and it contains illustrations in pen, crayon, and ink and the collection "pays homage to the primary gods and goddesses that comprise the Afro-Cuban religion of Santer'a." The "Introduction" near the top of the page, is a good place for visitors to start learning about Pozo, who was a Parson's School of Design-trained, Cuban artist who died at the age of 47. The "Biographical Sketch" is worth looking at as well. Examples of his colorful, heavily patterned and symbolism-intensive drawings of Santeria gods and goddesses can be found in the link "Gallery". The description of each drawing is given in English and Spanish. Finally, visitors interested in more information on the Santeria, can look at the "Further Readings" link for authoritative books on the subject.

216

Sulla struttura eletronica del nitrobenzolo  

Microsoft Academic Search

Riassunto  È presentato un calcolo di alcune grandezze fisiche del nitrobenzolo mediante il metodo M.O. con una ragionevole scelta dei\\u000a parametri necessari. Per il momento elettrico, la frequenza del primo massimo di assorbimento nell’ultravioletto, le densità\\u000a elettroniche, gli ordini di legame, gli indici di valenza libera e l’energia di risonanza si ottengono valori in ottimo accordo\\u000a con le previsioni. Anche il

M. Simonetta; A. Vaciago

1954-01-01

217

African swine fever virus morphogenesis.  

PubMed

This review summarizes recent structural and molecular biology studies related to the morphogenesis of African swine fever virus (ASFV). ASFV possesses icosahedral morphology and is constituted by four concentric layers: the central nucleoid, the core shell, the inner envelope and the icosahedral capsid. The extracellular virus acquires an external envelope by budding through the plasma membrane. The genes coding for 19 of the 54 structural proteins of the ASFV particle are known and the localization within the virion of 18 of these components has been identified. ASFV morphogenesis occurs in specialized areas in the cytoplasm, named viral factories, which are proximal to the microtubule organization center near the nucleus. Investigations of the different steps of morphogenesis by immunocytochemical and electron microscopy techniques, as well as molecular biology and biochemical studies, have shed light on the formation of the different domains of the virus particle, including the recognition of endoplasmic reticulum membranes as the precursors of the virus inner envelope, the progressive formation of the capsid on the convex face of the inner envelope and the simultaneous assembly of the core shell on the concave side of the envelope, with the pivotal contribution of the virus polyproteins and their proteolytic processing by the virus protease for the development of this latter domain. The use of ASFV inducible recombinants as a tool for the study of the individual function of structural and nonstructural proteins has been determinant to understand their role in virus assembly and has provided new insights into the morphogenetic process. PMID:23059353

Salas, María L; Andrés, Germán

2012-10-08

218

Viruses and Interactomes in Translation*  

PubMed Central

A decade of high-throughput screenings for intraviral and virus-host protein-protein interactions led to the accumulation of data and to the development of theories on laws governing interactome organization for many viruses. We present here a computational analysis of intraviral protein networks (EBV, FLUAV, HCV, HSV-1, KSHV, SARS-CoV, VACV, and VZV) and virus-host protein networks (DENV, EBV, FLUAV, HCV, and VACV) from up-to-date interaction data, using various mathematical approaches. If intraviral networks seem to behave similarly, they are clearly different from the human interactome. Viral proteins target highly central human proteins, which are precisely the Achilles' heel of the human interactome. The intrinsic structural disorder is a distinctive feature of viral hubs in virus-host interactomes. Overlaps between virus-host data sets identify a core of human proteins involved in the cellular response to viral infection and in the viral capacity to hijack the cell machinery for viral replication. Host proteins that are strongly targeted by a virus seem to be particularly attractive for other viruses. Such protein-protein interaction networks and their analysis represent a powerful resource from a therapeutic perspective.

Meyniel-Schicklin, Laurene; de Chassey, Benoit; Andre, Patrice; Lotteau, Vincent

2012-01-01

219

21 CFR 866.3360 - Lymphocytic choriomeningitis virus serological reagents.  

Code of Federal Regulations, 2013 CFR

... false Lymphocytic choriomeningitis virus serological reagents. 866.3360 Section...866.3360 Lymphocytic choriomeningitis virus serological reagents. (a) Identification. Lymphocytic choriomeningitis virus serological reagents are devices...

2013-04-01

220

Respiratory syncytial virus infection disrupts monolayer integrity and function in cystic fibrosis airway cells.  

PubMed

Background: Respiratory Syncytial Virus (RSV) infection is a common contributor to pulmonary symptoms in children with cystic fibrosis (CF). Here we examined RSV infection in immortalized bronchial epithelial cells (CFBE41o-) expressing wild-type (wt) or F508del cystic fibrosis transmembrane conductance regulator (CFTR), for monolayer integrity and RSV replication. Methods: CFBE41o- monolayers expressing wt or F508del CFTR were grown on permeable supports and inoculated with RSV A2 strain. Control experiments utilized UV-inactivated RSV and heat-killed RSV. Monolayer resistance and RSV production was monitored for up to six days post-infection. Results: Within 24 h, a progressive decrease in monolayer resistance was observed in RSV infected F508del CFBE41o- cells, while the monolayer integrity of RSV infected wt CFTR CFBE41o- cells remained stable. RSV replication was necessary to disrupt F508del CFBE41o- monolayers as UV-irradiated and heat killed RSV had no effect on monolayer integrity, with an earlier and much more pronounced peak in RSV titer noted in F508del relative to wt CFTR-expressing cells. RSV infection of wt CFBE41o- monolayers also resulted in blunting of CFTR response. Conclusions: These findings identify an enhanced sensitivity of CFBE41o- cells expressing F508del CFTR to RSV infection, replication and monolayer disruption independent of the cellular immune response, and provide a novel mechanism by which cystic fibrosis airway epithelia are susceptible to RSV-dependent injury. PMID:24056672

Kong, Michele; Maeng, Patrick; Hong, Jeong; Szczesniak, Rhonda; Sorscher, Eric; Sullender, Wayne; Clancy, John Paul

2013-09-19

221

Respiratory Syncytial Virus Infection Disrupts Monolayer Integrity and Function in Cystic Fibrosis Airway Cells  

PubMed Central

Background: Respiratory Syncytial Virus (RSV) infection is a common contributor to pulmonary symptoms in children with cystic fibrosis (CF). Here we examined RSV infection in immortalized bronchial epithelial cells (CFBE41o-) expressing wild-type (wt) or F508del cystic fibrosis transmembrane conductance regulator (CFTR), for monolayer integrity and RSV replication. Methods: CFBE41o- monolayers expressing wt or F508del CFTR were grown on permeable supports and inoculated with RSV A2 strain. Control experiments utilized UV-inactivated RSV and heat-killed RSV. Monolayer resistance and RSV production was monitored for up to six days post-infection. Results: Within 24 h, a progressive decrease in monolayer resistance was observed in RSV infected F508del CFBE41o- cells, while the monolayer integrity of RSV infected wt CFTR CFBE41o- cells remained stable. RSV replication was necessary to disrupt F508del CFBE41o- monolayers as UV-irradiated and heat killed RSV had no effect on monolayer integrity, with an earlier and much more pronounced peak in RSV titer noted in F508del relative to wt CFTR-expressing cells. RSV infection of wt CFBE41o- monolayers also resulted in blunting of CFTR response. Conclusions: These findings identify an enhanced sensitivity of CFBE41o- cells expressing F508del CFTR to RSV infection, replication and monolayer disruption independent of the cellular immune response, and provide a novel mechanism by which cystic fibrosis airway epithelia are susceptible to RSV-dependent injury.

Michele, Kong; Patrick, Maeng; Jeong, Hong; Rhonda, Szczesniak; Eric, Sorscher; Wayne, Sullender; John Paul, Clancy

2013-01-01

222

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

Code of Federal Regulations, 2013 CFR

...2013-01-01 2013-01-01 false Bovine Virus Diarrhea Vaccine, Killed Virus. 113.215 Section 113.215 Animals and...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS;...

2013-01-01

223

Primary Virus-Cell Interactions in the Immunofluorescence Assay of Venezuelan Equine Encephalomyelitis Virus.  

National Technical Information Service (NTIS)

The conditions under which Venezuelan equine encephalomyelitis (VEE) virus attached to host cells markedly influenced the assay of virus by the fluorescent cell-counting technique. When virus inoculum was centrifuged onto McCoy cell monolayers, approximat...

N. Hahon K. O. Cooke

1967-01-01

224

Morphology and morphogenesis of Soldado virus (Hughes group); similarities with viruses of the Bunyaviridae family  

Microsoft Academic Search

Summary Morphology and morphogenesis of Soldado virus were studied in the brain of infected suckling mice. The results suggest this virus and other viruses of Hughes group may be classified as members of Bunyaviridae family.

C. Chastel; G. Rogues; J.-C. Beaucournu

1979-01-01

225

Why do RNA viruses recombine?  

PubMed Central

Recombination occurs in many RNA viruses and can be of major evolutionary significance. However, rates of recombination vary dramatically among RNA viruses, which can range from clonal to highly recombinogenic. Here, we review the factors that might explain this variation in recombination frequency and show that there is little evidence that recombination is favoured by natural selection to create advantageous genotypes or purge deleterious mutations, as predicted if recombination functions as a form of sexual reproduction. Rather, recombination rates seemingly reflect larger-scale patterns of viral genome organization, such that recombination may be a mechanistic by-product of the evolutionary pressures acting on other aspects of virus biology.

Simon-Loriere, Etienne; Holmes, Edward C.

2012-01-01

226

NEUTRALIZATION OF EPIDEMIC INFLUENZA VIRUS  

PubMed Central

A linear relationship exists between the logarithm of the quantity of epidemic influenza virus neutralized and the logarithm of the quantity of antiserum which is capable of achieving this result. This relationship is the same for the serum of a ferret convalescent from experimental influenza as for the serum of a rabbit immunized with the virus. By means of the linear relationship between virus and antiserum it is possible to determine a fixed, rather than a relative, value for the neutralizing capacity of a serum.

Horsfall, Frank L.

1939-01-01

227

Enzyme-linked immunosorbent assay-based detection of antibodies to antigenic subtypes of infectious bursal disease viruses of chickens.  

PubMed Central

An enzyme-linked immunosorbent assay (ELISA) using a fragment of the infectious bursal disease virus (IBDV) VP2 gene expressed in baculovirus was developed. A 944-bp portion of the VP2 gene from the Del-A strain of IBDV was ligated into the pAc360 transfer vector and transfected into baculovirus, Recombinant baculoviruses were identified by dot blot hybridization. The recombinant baculovirus 9A5 expressed a 57-kDa VP2 fusion protein, which was immunoprecipitated. This baculovirus-expressed VP2 was used as an antigen in an ELISA (Ohio State University [OSU]-ELISA). Titers of sera from specific-pathogen-free chickens infected with different strains of IBDV in our laboratory were determined by the OSU-ELISA, commercial ELISAs, and a virus neutralization assay. The results indicate that all sera from the specific-pathogen-free chickens infected with IBDV strains contained high titers of neutralizing antibodies. Each of these antisera also tested positive with the commercial ELISA kits. The OSU-ELISA did not detect antibodies to all strains of IBDV tested. This ELISA detected antibodies to the antigenically similar Delaware variant strains Del-A, Del-E, and GLS but did not detect or detected very poorly antibodies to antigenically heterologous classic IBDV strains STC, D78, and BVM. Although the antiserum to the IN strain of IBDV contained a virus-neutralizing antibody titer, the OSU-ELISA did not detect antibodies in this serum, suggesting IN is antigenically heterologous to Del-A. Titers to the IN strain were detected with the commercial ELISA kits. The OSU-ELISA detected antibodies to the SAL strain, suggesting this virus is antigenically similar to Del-A, which is supported by previously reported vaccination and challenge studies. In conclusion, the OSU-ELISA could be used to detect antibodies to a subgroup of IBDV strains, while commercially available ELISA kits detected antibodies to all the antigenic subtypes of IBDV tested.

Jackwood, D J; Henderson, K S; Jackwood, R J

1996-01-01

228

Evolution of Computer Virus Concealment and AntiVirus Techniques: A Short Survey  

Microsoft Academic Search

This paper presents a general overview on evolution of concealment methods in computer viruses and defensive techniques employed by anti-virus products. In order to stay far from the anti-virus scanners, computer viruses gradually improve their codes to make them invisible. On the other hand, anti-virus technologies continually follow the virus tricks and methodologies to overcome their threats. In this process,

Babak Bashari Rad; Maslin Masrom; Suhaimi Ibrahim

2011-01-01

229

CROP VIRUSES AND VIRUS DISEASES: A GLOBAL PERSPECTIVE  

Microsoft Academic Search

Viruses were distinguished as a separate group of plant pathogens in the 1890s, as a consequence of pioneering studies in\\u000a Russia and the Netherlands (Bos, 2000). They have since received much attention from plant pathologists and more recently\\u000a from molecular biologists. Nevertheless, the information available on the distribution, prevalence, and importance of plant\\u000a viruses and the diseases they cause is

J. M. Thresh

230

Vesicular Stomatitis Virus and RNA Viruses as Gene Therapy Vectors  

Microsoft Academic Search

The ability of RNA viruses to efficiently reproduce in transformed cells was first recognized nearly 100 yr ago. However,\\u000a it wasn’t until the late 1990s that a resurrection of the interest in the ability of certain viruses to preferentially replicate\\u000a in malignant cells and less so in normal cells occurred, the curiosity being to evaluate whether these agents could be

Glen N. Barber

231

Antiviral Drugs for Viruses Other Than Human Immunodeficiency Virus  

PubMed Central

Most viral diseases, with the exception of those caused by human immunodeficiency virus, are self-limited illnesses that do not require specific antiviral therapy. The currently available antiviral drugs target 3 main groups of viruses: herpes, hepatitis, and influenza viruses. With the exception of the antisense molecule fomivirsen, all antiherpes drugs inhibit viral replication by serving as competitive substrates for viral DNA polymerase. Drugs for the treatment of influenza inhibit the ion channel M2 protein or the enzyme neuraminidase. Combination therapy with Interferon-? and ribavirin remains the backbone treatment for chronic hepatitis C; the addition of serine protease inhibitors improves the treatment outcome of patients infected with hepatitis C virus genotype 1. Chronic hepatitis B can be treated with interferon or a combination of nucleos(t)ide analogues. Notably, almost all the nucleos(t) ide analogues for the treatment of chronic hepatitis B possess anti–human immunodeficiency virus properties, and they inhibit replication of hepatitis B virus by serving as competitive substrates for its DNA polymerase. Some antiviral drugs possess multiple potential clinical applications, such as ribavirin for the treatment of chronic hepatitis C and respiratory syncytial virus and cidofovir for the treatment of cytomegalovirus and other DNA viruses. Drug resistance is an emerging threat to the clinical utility of antiviral drugs. The major mechanisms for drug resistance are mutations in the viral DNA polymerase gene or in genes that encode for the viral kinases required for the activation of certain drugs such as acyclovir and ganciclovir. Widespread antiviral resistance has limited the clinical utility of M2 inhibitors for the prevention and treatment of influenza infections. This article provides an overview of clinically available antiviral drugs for the primary care physician, with a special focus on pharmacology, clinical uses, and adverse effects.

Razonable, Raymund R.

2011-01-01

232

Simultaneous detection of cucumber mosaic virus, tomato mosaic virus and potato virus Y by flow cytometry.  

PubMed

The simultaneous detection is described of cucumber mosaic virus (CMV), potato virus Y (PVY) and tomato mosaic virus (ToMV) by flow cytometry. Extracts from leaves of healthy and CMV or PVY infected plants were incubated with latex particles, each with a diameter of 3 microm. Extracts from ToMV infected or uninfected plants, however, were incubated with particles, each with a diameter of 6 microm. Beads were washed and incubated in succession with primary and secondary antibodies, the latter labeled with phycoerythrin (PE) or fluorescein (FITC). CMV and PVY were distinguished on the basis of the fluorescence emitted by FITC and PE; ToMV was distinguished from CMV and PVY on the basis of the different diameter (6 microm) of the particles on which it was adsorbed. The three viruses were detected also by another approach. Latex particles with a diameter of 3, 6 and 10 microm were separately sensitized with antibodies specific for CMV, PVY and ToMV. An equal number of sensitized particles was mixed and incubated with the plant extracts containing the three viruses and then with anti-CMV, anti-PVY and anti-ToMV antibodies labeled with FITC. The study describes also a virus purification method based on the use of antibody coated latex particles. The method is simple technically and applicable to the purification of large as well as minute amounts of different viruses (CMV, PVY and ToMV). PMID:9504759

Iannelli, D; D'Apice, L; Cottone, C; Viscardi, M; Scala, F; Zoina, A; Del Sorbo, G; Spigno, P; Capparelli, R

1997-12-01

233

Toscana Virus in Spain  

PubMed Central

Toscana virus (TOSV, Phlebovirus, family Bunyaviridae) infection is one of the most prevalent arboviruses in Spain. Within the objectives of a multidisciplinary network, a study on the epidemiology of TOSV was conducted in Granada, in southern Spain. The overall seroprevalence rate was 24.9%, significantly increasing with age. TOSV was detected in 3 of 103 sandfly pools by viral culture or reverse transcription–polymerase chain reaction from a region of the L gene. Nucleotide sequence homology was 99%–100% in TOSV from vectors and patients and 80%–81% compared to the Italian strain ISS Phl.3. Sequencing of the N gene of TOSV isolates from patients and vectors indicated 87%–88% and 100% homology at the nucleotide and amino acid levels, respectively, compared to the Italian strain. These findings demonstrate the circulation of at least 2 different lineages of TOSV in the Mediterranean basin, the Italian lineage and the Spanish lineage.

Sanbonmatsu-Gamez, Sara; Perez-Ruiz, Mercedes; Collao, Ximena; Sanchez-Seco, Maria Paz; Morillas-Marquez, Francisco; de la Rosa-Fraile, Manuel; Navarro-Mari, Jose Maria; Tenorio, Antonio

2005-01-01

234

Feline immunodeficiency virus latency  

PubMed Central

Despite highly effective anti-retroviral therapy, HIV is thought to persist in patients within long-lived cellular reservoirs in the form of a transcriptionally inactive (latent) integrated provirus. Lentiviral latency has therefore come to the forefront of the discussion on the possibility of a cure for HIV infection in humans. Animal models of lentiviral latency provide an essential tool to study mechanisms of latency and therapeutic manipulation. Of the three animal models that have been described, the feline immunodeficiency virus (FIV)-infected cat is the most recent and least characterized. However, several aspects of this model make it attractive for latency research, and it may be complementary to other model systems. This article reviews what is known about FIV latency and chronic FIV infection and how it compares with that of other lentiviruses. It thereby offers a framework for the usefulness of this model in future research aimed at lentiviral eradication.

2013-01-01

235

Feline immunodeficiency virus latency.  

PubMed

Despite highly effective anti-retroviral therapy, HIV is thought to persist in patients within long-lived cellular reservoirs in the form of a transcriptionally inactive (latent) integrated provirus. Lentiviral latency has therefore come to the forefront of the discussion on the possibility of a cure for HIV infection in humans. Animal models of lentiviral latency provide an essential tool to study mechanisms of latency and therapeutic manipulation. Of the three animal models that have been described, the feline immunodeficiency virus (FIV)-infected cat is the most recent and least characterized. However, several aspects of this model make it attractive for latency research, and it may be complementary to other model systems. This article reviews what is known about FIV latency and chronic FIV infection and how it compares with that of other lentiviruses. It thereby offers a framework for the usefulness of this model in future research aimed at lentiviral eradication. PMID:23829177

McDonnel, Samantha J; Sparger, Ellen E; Murphy, Brian G

2013-07-06

236

Human immunodeficiency virus endocrinopathy  

PubMed Central

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.

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

2011-01-01

237

Genetic variability and heterogeneity of Venezuelan equine encephalitis virus vector Ochlerotatus taeniorhynchus (Diptera: Culicidae) populations of the Colombian Atlantic coast, based on microsatellite loci  

Microsoft Academic Search

In Colombia, the mosquito Ochlerotatus taeniorhyn- chus has been identified as an efficient vector of the epidemic-epi- zootic Venezuelan equine encephalitis virus. We evaluated the ge- netic variability and heterogeneity of this mosquito in Colombian populations using eight microsatellite DNA loci. Two hundred and ten mosquito specimens collected from seven populations of the Co- lombian Atlantic coast (San Bernardo del

F. Bello; V. Becerra

238

Varicella-zoster virus.  

PubMed Central

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.

Arvin, A M

1996-01-01

239

Varicella zoster virus vasculopathy  

PubMed Central

Objective: Varicella zoster virus (VZV) is an under-recognized yet treatable cause of stroke. No animal model exists for stroke caused by VZV infection of cerebral arteries. Thus, we analyzed cerebral and temporal arteries from 3 patients with VZV vasculopathy to identify features that will help in diagnosis and lead to a better understanding of VZV-induced vascular remodeling. Methods: Normal and VZV-infected cerebral and temporal arteries were examined histologically and by immunohistochemistry using antibodies directed against VZV, endothelium, and smooth muscle actin and myosin. Results: All VZV-infected arteries contained 1) a disrupted internal elastic lamina; 2) a hyperplastic intima composed of cells expressing ?-smooth muscle actin (?-SMA) and smooth muscle myosin heavy chain (SM-myosin) but not endothelial cells expressing CD31; and 3) decreased medial smooth muscle cells. The location of VZV antigen, degree of neointimal thickening, and disruption of the media were related to the duration of disease. Conclusions: The presence of VZV primarily in the adventitia early in infection and in the media and intima later supports the notion that after reactivation from ganglia, VZV spreads transaxonally to the arterial adventitia followed by transmural spread of virus. Disruption of the internal elastic lamina, progressive intimal thickening with cells expressing ?-SMA and SM-MHC, and decreased smooth muscle cells in the media are characteristic features of VZV vasculopathy. Stroke in VZV vasculopathy may result from changes in arterial caliber and contractility produced in part by abnormal accumulation of smooth muscle cells and myofibroblasts in thickened neointima and disruption of the media.

Nagel, M.A.; Traktinskiy, I.; Azarkh, Y.; Kleinschmidt- DeMasters, B.; Hedley-Whyte, T.; Russman, A.; VanEgmond, E.M.; Stenmark, K.; Frid, M.; Mahalingam, R.; Wellish, M.; Choe, A.; Cordery-Cotter, R.; Cohrs, R.J.

2011-01-01

240

Japanese Encephalitis Virus Vaccine Inactivated  

Center for Biologics Evaluation and Research (CBER)

... Complete List of Vaccines Licensed for Immunization and Distribution in the US. -. Japanese Encephalitis Virus Vaccine Inactivated. -. JE-Vax. -. -. -. ... More results from www.fda.gov/biologicsbloodvaccines/vaccines/approvedproducts

241

Viruses in Soil and Groundwater.  

National Technical Information Service (NTIS)

Human viruses usually gain access to soil systems through intentional or unintentional discharges of domestic wastewater. Intentional land treatment/disposal systems represent an attractive alternative to surface water discharges, providing both economic ...

J. M. Vaughn E. F. Landry

1981-01-01

242

Novel vaccines against influenza viruses  

PubMed Central

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.

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

2011-01-01

243

Feasibility Study: Rubella Virus Vaccine.  

National Technical Information Service (NTIS)

The attenuated strain of rubella virus, was serially passed 14 times in AGMK cells and the markers of attenuation were verified. Rubella hemagglutinin and complement fixing antigen were produced in good titers in BHK-21 cells in sufficient quantities for ...

R. G. Brackett

1967-01-01

244

Virus Diseases of Small Fruits,  

National Technical Information Service (NTIS)

The illustrated handbook was compiled by international authorities on virus and viruslike diseases of small fruits. Crops covered are in the plant genera Fragaria (strawberry), Vaccinium (blueberry and cranberry), Ribes (currant and gooseberry), and Rubus...

R. H. Converse

1987-01-01

245

MEASLES VIRUS VACCINE LIVE (ATTENUVAX)  

Center for Biologics Evaluation and Research (CBER)

Text Version... Measles is a common childhood disease, caused by measles virus (paramyxovirus), that may be associated with serious complications and/or ... More results from www.fda.gov/downloads/biologicsbloodvaccines/vaccines

246

Bronchiolitis and Respiratory Syncytial Virus  

MedlinePLUS

ADVICE FOR PATIENTS Bronchiolitis and Respiratory Syncytial Virus B ronchiolitis is an infection that affects the lungs and breathing passages; the name “bronchiolitis” means inflammation of the small airways in the ...

247

Rapid Detection of Enveloped Viruses.  

National Technical Information Service (NTIS)

This report discusses the continuing effort to enhance the sensitivity of type A influenza virus detection systems utilizing the monoclonal antibodies to M-protein. Combinations of purified monoclonal antibodies to M-protein used as capture antibodies for...

D. J. Bucher

1986-01-01

248

Russian winter wheat mosaic virus  

Technology Transfer Automated Retrieval System (TEKTRAN)

The chapter contains a description of the Winter wheat (Russian) mosaic disease symptoms, transmission and occurrence. Characteristics of the disease agent, Winter wheat (Russian) mosaic virus are outlined, as are control measures....

249

Viroids and hepatitis delta virus.  

PubMed

There is a subviral world, whose most prominent representatives are viroids. Despite being solely composed by a circular, highly structured RNA of ~250 to 400 nucleotides without protein-coding ability (all viruses code for one or more proteins), viroids can infect and incite specific diseases in higher plants. The RNA of human hepatitis delta virus (HDV), the smallest genome of an animal virus, displays striking similarities with viroids: It is circular, folds into a rodlike secondary structure, and replicates through a rolling-circle mechanism catalyzed by host enzymes and cis-acting ribozymes. However, HDV RNA is larger (~1700 nucleotides), encodes a protein in its antigenomic polarity (the ? antigen), and depends for transmission on hepatitis B virus. The presence of ribozymes in some viroids and in HDV RNA, along with their structural simplicity, makes them candidates for being molecular fossils of the RNA world that presumably preceded our extant world based on DNA and proteins. PMID:22932968

Flores, Ricardo; Ruiz-Ruiz, Susana; Serra, Pedro

2012-08-29

250

Arthropod viruses and small RNAs.  

PubMed

The recently characterized small RNAs provide a new paradigm for physiological studies. These molecules have been shown to be integral players in processes as diverse as development and innate immunity against bacteria and viruses in eukaryotes. Several of the well-characterized small RNAs including small interfering RNAs, microRNAs and PIWI-interacting RNAs are emerging as important players in mediating arthropod host-virus interactions. Understanding the role of small RNAs in arthropod host-virus molecular interactions will facilitate manipulation of these pathways for both management of arthropod pests of agricultural and medical importance, and for protection of beneficial arthropods such as honey bees and shrimp. This review highlights recent research on the role of small RNAs in arthropod host-virus interactions with reference to other host-pathogen systems. PMID:23932976

Vijayendran, Diveena; Airs, Paul M; Dolezal, Kelly; Bonning, Bryony C

2013-08-08

251

Chenopodium Quinoa Willd. as a local lesion host of Marmor cichorii Kví?ala ( Cichorium virus 1 Kv?.)  

Microsoft Academic Search

\\u000a Souhrn  Kví?alou (1956) popsaný virus skvrnitosti a žloutenky ?ekanky, známý pouze zCichorium intybus L. var.sativum Bl. byl mechanicky p?enesen naChenopodium Quinoa Willd., na jehož listech vyvolává žluté lokální nekrotické lese. Lese jsou podobné jako u 6 srovnávaných kmen? viru oby?ejné\\u000a okurkové mosaiky [Cucumis virus 1 (Doolittle) Smith,Marmor cucumeris var.vulgare Holmes], avšak projeví se za delší dobu po o?kování (9 dní).\\u000a \\u000a ??????  ????????

Jaroslav Br?ák

1960-01-01

252

Overview of hepatitis E virus  

Microsoft Academic Search

Hepatitis E virus (HEV) is an enterically transmitted virus usually presenting as an acute self-limiting disease. However,\\u000a mortality increases dramatically from around 1% to 20% in pregnant women. HEV has been the cause of very large outbreaks of\\u000a hepatitis in developing countries and is also responsible for a significant number of sporadic cases. It is clear that cases\\u000a occur outside

Susan Skidmore

2002-01-01

253

Measles virus antigen in panencephalitis  

Microsoft Academic Search

In a retrospective study of 42 cases with a histopathologic diagnosis of subacute sclerosing panencephalitis (SSPE) or similar panencephalitic processes, measles virus antigen was traced by means of indirect immunofluorescence (IF) and peroxidase-antiperoxidase (PAP) techniques on protease-pretreated histological sections from formol-fixed, paraffin-embedded brain biopsy or autopsy tissue, stored for up to 32 years. Measles virus antigen was detected in 28

H. Budka; H. Lassmann; Th. Popow-Kraupp

1982-01-01

254

Simian virus 40 in humans  

Microsoft Academic Search

Simian virus 40 (SV40) is a monkey virus that was administered to human populations by contaminated vaccines which were produced in SV40 naturally infected monkey cells. Recent molecular biology and epidemiological studies suggest that SV40 may be contagiously transmitted in humans by horizontal infection, independently from the earlier administration of SV40-contaminated vaccines. SV40 footprints in humans have been found associated

Fernanda Martini; Alfredo Corallini; Veronica Balatti; Silvia Sabbioni; Cecilia Pancaldi; Mauro Tognon

2007-01-01

255

Plant Viruses Transmitted by Whiteflies  

Microsoft Academic Search

One-hundred and fourteen virus species are transmitted by whiteflies (family Aleyrodidae). Bemisia tabaci transmits 111 of these species while Trialeurodes vaporariorum and T. abutilonia transmit three species each. B. tabaci and T. vaporariorum are present in the European–Mediterranean region, though the former is restricted in its distribution. Of the whitefly-transmitted virus species, 90% belong to the Begomovirus genus, 6% to

David R. Jones

2003-01-01

256

Transient inhibition of polyoma virus synthesis by sendai virus (parainfluenza I). II. Mechanism of the interference by inactivated virus.  

PubMed

The mechanism of the transient inhibition of polyoma virus synthesis by betapropiolactone-inactivated Sendai virus was studied. Polyoma virus early functions did not appear to be affected, although deoxyribonucleic acid (DNA) and structural protein synthesis were inhibited 60 and 35% respectively. The inhibition of macromolecular synthesis was not sufficient to account for the 90% inhibition of infectious progeny formation. Encapsidation of polyoma DNA into mature virions appears to be completely inhibited after superinfection by beta-propiolactone-inactivated Sendai virus. Ultraviolet irradiation of live or beta-propiolactone-inactivated Sendai virus preparations abolishes the interfering capacity, indicating that a functional Sendai virus ribonucleic acid molecule is the interfering component. PMID:4345489

Smith, G L; Consigli, R A

1972-12-01

257

Transient Inhibition of Polyoma Virus Synthesis by Sendai Virus (Parainfluenza I) II. Mechanism of the Interference by Inactivated Virus 1  

PubMed Central

The mechanism of the transient inhibition of polyoma virus synthesis by betapropiolactone-inactivated Sendai virus was studied. Polyoma virus early functions did not appear to be affected, although deoxyribonucleic acid (DNA) and structural protein synthesis were inhibited 60 and 35% respectively. The inhibition of macromolecular synthesis was not sufficient to account for the 90% inhibition of infectious progeny formation. Encapsidation of polyoma DNA into mature virions appears to be completely inhibited after superinfection by beta-propiolactone-inactivated Sendai virus. Ultraviolet irradiation of live or beta-propiolactone-inactivated Sendai virus preparations abolishes the interfering capacity, indicating that a functional Sendai virus ribonucleic acid molecule is the interfering component.

Smith, Gary L.; Consigli, Richard A.

1972-01-01

258

Virus detection using nanoelectromechanical devices  

NASA Astrophysics Data System (ADS)

We have used a resonating mechanical cantilever to detect immunospecific binding of viruses, captured from liquid. As a model virus, we used a nonpathogenic insect baculovirus to test the ability to specifically bind and detect small numbers of virus particles. Arrays of surface micromachined, antibody-coated polycrystalline silicon nanomechanical cantilever beams were used to detect binding from various concentrations of baculoviruses in a buffer solution. Because of their small mass, the 0.5 ?m×6 ?m cantilevers have mass sensitivities on the order of 10-19 g/Hz, enabling the detection of an immobilized AcV1 antibody monolayer corresponding to a mass of about 3×10-15 g. With these devices, we can detect the mass of single-virus particles bound to the cantilever. Resonant frequency shift resulting from the adsorbed mass of the virus particles distinguished solutions of virus concentrations varying between 105 and 107 pfu/ml. Control experiments using buffer solutions without baculovirus showed small amounts (<50 attograms) of nonspecific adsorption to the antibody layer.

Ilic, B.; Yang, Y.; Craighead, H. G.

2004-09-01

259

Virus-Like Particles, Methods of Preparation, and Immunogenic Compositions.  

National Technical Information Service (NTIS)

Briefly described, virus-like particles, methods of preparing virus-like particles, immunogenic compositions that include virus-like particles, and methods of liciting an immune response using immunogenic compositions that include virus-like particles are...

C. Yang Q. Yao R. W. Compans S. M. Kang

2003-01-01

260

9 CFR 113.203 - Feline Panleukopenia Vaccine, Killed Virus.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2010-01-01 false Feline Panleukopenia Vaccine, Killed Virus. 113.203...Killed Virus Vaccines § 113.203 Feline Panleukopenia Vaccine, Killed Virus. Feline Panleukopenia Vaccine, Killed Virus,...

2010-01-01

261

9 CFR 113.203 - Feline Panleukopenia Vaccine, Killed Virus.  

Code of Federal Regulations, 2010 CFR

...2009-01-01 2009-01-01 false Feline Panleukopenia Vaccine, Killed Virus. 113.203...Killed Virus Vaccines § 113.203 Feline Panleukopenia Vaccine, Killed Virus. Feline Panleukopenia Vaccine, Killed Virus,...

2009-01-01

262

Polynucleotide Ligase Activity in Cells Infected with Simian Virus 40, Polyoma Virus, or Vaccinia Virus  

PubMed Central

The conversion of simian virus 40 (SV40) component II deoxyribonucleic acid to component I has been used to assay polynucleotide ligase in extracts of tissue culture cells. All cell types examined, including chicken, hamster, mouse, monkey, and human cells, contained adenosine triphosphate-dependent ligase. After infection of mouse embryo, monkey kidney, and HeLa cells with polyoma virus, SV40, and vaccinia virus, respectively, the enzyme activity increased, but its cofactor requirement was unchanged. In vaccinia virus-infected cells, the increased activity was localized in the cytoplasm. Ligase induction occurred in the presence of cytosine arabinoside but was prevented by puromycin. Rifampicin blocked the production of infectious vaccinia particles but had little effect on the induction of ligase.

Sambrook, J.; Shatkin, A. J.

1969-01-01

263

Structure of viruses: a short history.  

PubMed

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. Starting in the 1990s, these enveloped viruses were studied by combining cryo-electron microscopy of the whole virus with X-ray crystallography of their protein components. These structures gave information on virus assembly, virus neutralization by antibodies, and virus fusion with and entry into the host cell. The same techniques were also employed in the study of complex bacteriophages that were too large to crystallize. Nevertheless, there still remained many pleomorphic, highly pathogenic viruses that lacked the icosahedral symmetry and homogeneity that had made the earlier structural investigations possible. Currently some of these viruses are starting to be studied by combining X-ray crystallography with cryo-electron tomography. PMID:23889891

Rossmann, Michael G

2013-05-01

264

FENOLOGÍA DEL CULTIVO DEL CHILE (CAPSICUM ANNUUM L.)  

Microsoft Academic Search

RESUMEN Datos diarios de temperaturas máximas y mínimas del aire fueron usados para determinar las unidades calor, que sirvieron como referencia para definir las principales etapas fenológicas en seis tipos diferentes de chile (Capsicum annuum). Las unidades calor sirvieron para inferir el período de mayor requerimiento de nutrimentos, así como la relación con la sintomatología de las enfermedades más importantes

Salvador Montes Hernández; Elena Heredia García; J. Alfonso; Aguirre Gómez

265

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 false Coat Protein of Watermelon Mosaic 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;...

2013-07-01

266

Space as a Metafictional Marker: Borges' 'Tema del traidor y del héroe' and Bertolucci's Strategia del ragno  

Microsoft Academic Search

:In this study, I analyse space as a key marker of the metafictional characteristic of Jorge Luis Borges' story 'Tema del traidor y del héroe' (in Ficciones) and Bernardo Bertolucci's film Strategia del ragno. I contend that the presentation of space – this understudied 'other' with regard to time in criticism of Borges – is a major aspect of the

Ilka Kressner

267

Space as a Metafictional Marker: Borges' 'Tema del traidor y del héroe' and Bertolucci's Strategia del ragno  

Microsoft Academic Search

In this study, I analyse space as a key marker of the metafictional characteristic of Jorge Luis Borges' story 'Tema del traidor y del héroe' (in Ficciones) and Bernardo Bertolucci's film Strategia del ragno. I contend that the presentation of space – this understudied 'other' with regard to time in criticism of Borges – is a major aspect of the

Ilka Kressner

268

Considerazioni sulla proprieta' insulino-legante del siero del soggetto normale e del diabetico mai trattato con insulina  

Microsoft Academic Search

Riassunto Gli AA. rilevano che i sieri dell'individuo normale e del diabetico mai trattato con insulina sono provvisti di proprietà insulino-legante di entità analoga. In alcuni sieri, sia del soggetto normale che del diabetico, è presente un'attività insulino-legante superiore ai valori massimi normali, che diminuisce dopo aggiunta di µU 500 di insulina bovina.

Michele Lunetta; Giuseppe Calcagno; Luciano Motta; Turiddu Lombardo

1968-01-01

269

Occurrence of Six Honeybee Viruses in Diseased Austrian Apiaries  

Microsoft Academic Search

The occurrence, prevalence, and distribution patterns of acute bee paralysis virus (ABPV), black queen cell virus (BQCV), chronic bee paralysis virus (CBPV), deformed wing virus (DWV), Kashmir bee virus (KBV), and sacbrood virus (SBV) were investigated in 90 Austrian honeybee colonies suffering from symptoms of depop- ulation, sudden collapse, paralysis, or dark coloring by employing reverse transcription-PCR. Infestation with parasites

Olga Berenyi; Tamas Bakonyi; Irmgard Derakhshifar; Hemma Koglberger; Norbert Nowotny

2006-01-01

270

Stochastic analysis of virus transport in aquifers  

USGS Publications Warehouse

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 associated with solid surfaces than to the inactivation rate of viruses in solution.

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

1999-01-01

271

Recombinant infectious bursal disease virus carrying hepatitis C virus epitopes.  

PubMed

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

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

2010-11-24

272

Emerging and Re-emerging Swine Viruses.  

PubMed

In the past two decades or so, a number of viruses have emerged in the global swine population. Some, such as porcine reproductive and respiratory syndrome virus (PRRSV) and porcine circovirus type 2 (PCV2), cause economically important diseases in pigs, whereas others such as porcine torque teno virus (TTV), now known as Torque teno sus virus (TTSuV), porcine bocavirus (PBoV) and related novel parvoviruses, porcine kobuvirus, porcine toroviruses (PToV) and porcine lymphotropic herpesviruses (PLHV), are mostly subclinical in swine herds. Although some emerging swine viruses such as swine hepatitis E virus (swine HEV), porcine endogenous retrovirus (PERV) and porcine sapovirus (porcine SaV) may have a limited clinical implication in swine health, they do pose a potential public health concern in humans due to zoonotic (swine HEV) or potential zoonotic (porcine SaV) and xenozoonotic (PERV, PLHV) risks. Other emerging viruses such as Nipah virus, Bungowannah virus and Menangle virus not only cause diseases in pigs but some also pose important zoonotic threat to humans. This article focuses on emerging and re-emerging swine viruses that have a limited or uncertain clinical and economic impact on pig health. The transmission, epidemiology and pathogenic potential of these viruses are discussed. In addition, the two economically important emerging viruses, PRRSV and PCV2, are also briefly discussed to identify important knowledge gaps. PMID:22225855

Meng, X J

2012-01-01

273

Viruses and viruslike particles of eukaryotic algae.  

PubMed Central

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

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

1991-01-01

274

Phylogenetic Properties of RNA Viruses  

PubMed Central

A new word, phylodynamics, was coined to emphasize the interconnection between phylogenetic properties, as observed for instance in a phylogenetic tree, and the epidemic dynamics of viruses, where selection, mediated by the host immune response, and transmission play a crucial role. The challenges faced when investigating the evolution of RNA viruses call for a virtuous loop of data collection, data analysis and modeling. This already resulted both in the collection of massive sequences databases and in the formulation of hypotheses on the main mechanisms driving qualitative differences observed in the (reconstructed) evolutionary patterns of different RNA viruses. Qualitatively, it has been observed that selection driven by the host immune response induces an uneven survival ability among co-existing strains. As a consequence, the imbalance level of the phylogenetic tree is manifestly more pronounced if compared to the case when the interaction with the host immune system does not play a central role in the evolutive dynamics. While many imbalance metrics have been introduced, reliable methods to discriminate in a quantitative way different level of imbalance are still lacking. In our work, we reconstruct and analyze the phylogenetic trees of six RNA viruses, with a special emphasis on the human Influenza A virus, due to its relevance for vaccine preparation as well as for the theoretical challenges it poses due to its peculiar evolutionary dynamics. We focus in particular on topological properties. We point out the limitation featured by standard imbalance metrics, and we introduce a new methodology with which we assign the correct imbalance level of the phylogenetic trees, in agreement with the phylodynamics of the viruses. Our thorough quantitative analysis allows for a deeper understanding of the evolutionary dynamics of the considered RNA viruses, which is crucial in order to provide a valuable framework for a quantitative assessment of theoretical predictions.

Pompei, Simone; Loreto, Vittorio; Tria, Francesca

2012-01-01

275

Adaptive Mutations in Sindbis Virus E2 and Ross River Virus E1 That Allow Efficient Budding of Chimeric Viruses  

Microsoft Academic Search

Alphavirus glycoproteins E2 and E1 form a heterodimer that is required for virus assembly. We have studied adaptive mutations in E2 of Sindbis virus (SIN) and E1 of Ross River virus (RR) that allow these two glycoproteins to interact more efficiently in a chimeric virus that has SIN E2 but RR E1. These mutations include K129E, K131E, and V237F in

KYONGMIN HWANG KIM; ELLEN G. STRAUSS; JAMES H. STRAUSS

2000-01-01

276

Adeno-associated viruses.  

PubMed

Adeno-associated virus (AAV) vectors have evolved over the past decade as a particularly useful gene -vector for in vivo applications. In contrast to oncoretro- and lentiviral vectors, this vector stays essentially episomal after gene transfer, making it safer because of the absence of insertional mutagenesis. AAV's non-pathogenicity is a further advantage. For decades, this vector could only be produced at a small scale for research purposes and, eventually, used at very small doses for clinical studies, because only transfection methods were available, which have limited scalability. However, since the development of scalable production methods, this bottleneck is resolved and, from a technical point of view, large quantities of AAV vectors can be produced, opening the possibility of using AAV vectors for whole body treatments in gene therapy trials. This chapter presents the basic principles of small- and large-scale production procedures as well as detailed procedure of small-scale production, purification, and analytical protocols for AAV vectors. In Chapter 10, the reader will find a large-scale production method based on the use of the insect cell/baculovirus system. PMID:21590399

Mezzina, Mauro; Merten, Otto-Wilhelm

2011-01-01

277

Virus-Induced Neuronal Apoptosis Blocked by the Herpes Simplex Virus Latency-Associated Transcript  

Microsoft Academic Search

Latent infections with periodic reactivation are a common outcome after acute infection with many viruses. The latency-associated transcript (LAT) gene is required for wild-type reactivation of herpes simplex virus (HSV). However, the underlying mechanisms remain unclear. In rabbit trigeminal ganglia, extensive apoptosis occurred with LAT- virus but not with LAT+ viruses. In addition, a plasmid expressing LAT blocked apoptosis in

Guey-Chuen Perng; Clinton Jones; Janice Ciacci-Zanella; Melissa Stone; Gail Henderson; Ada Yukht; Susan M. Slanina; Florence M. Hofman; Homayon Ghiasi; Anthony B. Nesburn; Steven L. Wechsler

2000-01-01

278

Synthesis of Virus-Specific Proteins in Cells Infected with Venezuelan Equine Encephalomyelitis Virus.  

National Technical Information Service (NTIS)

The use of polyacrylamide jells has facilitated the investigation of virus-specific proteins both in the form of virions and in cells infected by the virus. This method has made possible the separation of virus-specific proteins of the polio-virus and the...

F. I. Ershov L. V. Uryvaev V. M. Zhdanov

1971-01-01

279

Mechanisms for enveloped virus budding: Can some viruses do without an ESCRT?  

Microsoft Academic Search

Many enveloped viruses complete their replication cycle by forming vesicles that bud from the plasma membrane. Some viruses encode “late” (L) domain motifs that are able to hijack host proteins involved in the vacuolar protein sorting (VPS) pathway, a cellular budding process that gives rise to multivesicular bodies and that is topologically equivalent to virus budding. Although many enveloped viruses

Benjamin J. Chen; Robert A. Lamb

2008-01-01

280

Protection against respiratory infection with bovine virus diarrhoea virus by passively acquired antibody  

Microsoft Academic Search

Howard, C. J., Clarke, M. C. and Brownlie, J., 1989. Protection against respiratory infection with bovine virus diarrhoea virus by passively acquired antibody. Vet. Microbiol., 19: 195-203. Susceptibility to infection with bovine virus diarrhoea virus (BVDV) was compared for calves with varying amounts of specific antibody in their sera passively acquired from the ingestion of colostrum. Challenge consisted of intranasal

C. J. HOWARD; M. C. CLARKE; J. BROWNLIE

1989-01-01

281

Sendai Virus and Herpes Virus Type 1 Induce Apoptosis in Human Peripheral Blood Mononuclear Cells  

Microsoft Academic Search

Recent reports suggest that several viruses, besides human immunodeficiency virus, induce apoptosis in infected cells. We report here that Sendai virus or Herpes simplex virus type 1 (HSV-1), two potent inducers of interferon-?, caused cell death in a consistent number of human peripheral blood mononuclear cells. A careful analysis of infected cells by different techniques, such as optical and electron

Franco Tropea; Leonarda Troiano; Daniela Monti; Elena Lovato; Walter Malorni; Gabriella Rainaldi; Paolo Mattana; Giuseppe Viscomi; Maria Cristina Ingletti; Marinella Portolani; Claudio Cermelli; Andrea Cossarizza; Claudio Franceschi

1995-01-01

282

Kupe Virus, a New Virus in the Family Bunyaviridae, Genus Nairovirus, Kenya  

Microsoft Academic Search

We have previously described isolation and preliminary identification of a virus related to Dugbe virus (DUGV), family Bunyaviridae, genus Nairovirus. Six isolates of the virus were obtained from pools of Amblyomma gemma and Rhipicephalus pulchellus ticks collected from hides of cattle in Nairobi, Kenya, in October 1999. We report results of further characterization of this virus, including growth kinetics in

Mary B. Crabtree; Rosemary Sang; Barry R. Miller

2009-01-01

283

Mouse Neuroinvasive Phenotype of West Nile Virus Strains Varies Depending upon Virus Genotype  

Microsoft Academic Search

Despite recent advances in the genetics of West Nile (WN) virus, relatively little is known about the molecular basis of virulence of this virus. In particular, although the genotype of the WN virus strain that was recently introduced into North America has been determined, there have been few experimental studies on the virulence phenotype of the virus. We compared genetic

David W. C. Beasley; Li Li; Miguel T. Suderman; Alan D. T. Barrett

2002-01-01

284

Nyamanini and Midway Viruses Define a Novel Taxon of RNA Viruses in the Order Mononegavirales  

Microsoft Academic Search

Here, we report the sequencing and classification of Nyamanini virus (NYMV) and Midway virus (MIDWV), two antigenically related viruses that were first isolated in 1957 and 1966, respectively. Although these viruses have been cultured multiple times from cattle egrets, seabirds, and their ticks, efforts to classify them taxonomically using conventional serological and electron microscopic approaches have failed completely. We used

Kathie A. Mihindukulasuriya; Nang L. Nguyen; Guang Wu; Henry V. Huang; Vsevolod L. Popov; Robert B. Tesh; David Wang

2009-01-01

285

GENOMIC SEQUENCING OF DEER TICK VIRUS AND PHYLOGENY OF POWASSAN-RELATED VIRUSES OF NORTH AMERICA  

Microsoft Academic Search

Powassan (POW) virus is responsible for central nervous system infection in humans in North America and the eastern parts of Russia. Recently, a new flavivirus, deer tick (DT) virus, related to POW virus was isolated in the United States, but neither its pathogenic potential in human nor the taxonomic relationship with POW virus has been elucidated. In this study, we

G. KUNO; H. ARTSOB; N. KARABATSOS; K. R. TSUCHIYA; G. J. J. CHANG

2001-01-01

286

GB virus C\\/hepatitis G virus replicates in human haematopoietic cells and vascular endothelial cells  

Microsoft Academic Search

A novel flavivirus, GB virus C (GBV-C)\\/hepatitis G virus (HGV), has been detected in chronic liver disease patients. It is known that the viral RNA can be detected in C 5% of American blood donors. However, the implications for liver disease and the sites of virus replication remain unknown. Possible sites of virus replication were studied by using cell lines

Atsushi Handa; Kevin E. Brown

287

Genetic Diversity in RNA Virus Quasispecies Is Controlled by Host-Virus Interactions  

Microsoft Academic Search

Many RNA viruses have genetically diverse populations known as quasispecies. Important biological char- acteristics may be related to the levels of diversity in the quasispecies (quasispecies cloud size), including adaptability and host range. Previous work using Tobacco mosaic virus and Cucumber mosaic virus indicated that evolutionarily related viruses have very different levels of diversity in a common host. The quasispecies

WILLIAM L. SCHNEIDER; MARILYN J. ROOSSINCK

2001-01-01

288

Marina Del Rey Subregional Plan.  

National Technical Information Service (NTIS)

The Marina del Ray Subregional Plan was created for submission to the South Coast Regional Commission of the California Coastal Zone Conservation Commission. Since there are not, as yet, any other coastal subregional plans to use as examples, this plan fo...

M. McCoy C. Walecka

1975-01-01

289

Del Mar College GIS Program  

NSDL National Science Digital Library

Del Mar College offers a comprehensive geospatial program with certificates and Associates degrees in GIS. This site includes description of the program and courses, along with further contact information. By clicking on the link for "Geographic Information Systems" you may download a PDF with information about the program.

2010-10-28

290

Induction of protective immunity in swine by recombinant bamboo mosaic virus expressing foot-and-mouth disease virus epitopes  

Microsoft Academic Search

BACKGROUND: Plant viruses can be employed as versatile vectors for the production of vaccines by expressing immunogenic epitopes on the surface of chimeric viral particles. Although several viruses, including tobacco mosaic virus, potato virus X and cowpea mosaic virus, have been developed as vectors, we aimed to develop a new viral vaccine delivery system, a bamboo mosaic virus (BaMV), that

Chung-Da Yang; Jia-Teh Liao; Chen-Yen Lai; Ming-Hwa Jong; Chi-Ming Liang; Yeou-Liang Lin; Na-Sheng Lin; Yau-Heiu Hsu; Shu-Mei Liang

2007-01-01

291

Del Pezzo surfaces with Du Val singularities  

NASA Astrophysics Data System (ADS)

In this paper we study the problem of existence of orbifold Kaehler-Einstein metrics on del Pezzo surfaces of degree 1 with Du Val singular points. Moreover we compute global log canonical thresholds of del Pezzo surfaces of degree 1 with Du Val singularities and of del Pezzo surfaces of Picard rank 1 with Du Val singularities.

Kosta, Dimitra

2009-04-01

292

Realistic Approach to Virus Classification and Nomenclature  

Microsoft Academic Search

Prompted by Professor Lwoff's article ``Principles of Classification and Nomenclature of Viruses'' (Nature, 215, 13; 1967), Drs Gibbs and Harrison defend the idea of the cryptogram, and explain its advantage over a binomial system of nomenclature for viruses.

A. J. Gibbs

1968-01-01

293

Predicting "Airborne" Influenza Viruses: (Trans-) mission Impossible?  

PubMed Central

Repeated transmission of animal influenza viruses to humans has prompted investigation of the viral, host, and environmental factors responsible for transmission via aerosols or respiratory droplets. How do we determine – out of thousands of influenza virus isolates collected in animal surveillance studies each year – which viruses have the potential to become “airborne”, and hence pose a pandemic threat? Here, using knowledge from pandemic, zoonotic and epidemic viruses, we postulate that the minimal requirements for efficient transmission of an animal influenza virus between humans are: efficient virus attachment to (upper) respiratory tissues, replication to high titers in these tissues, and release and aerosolization of single virus particles. Investigating “airborne” transmission of influenza viruses is key to understand – and predict – influenza pandemics.

Sorrell, E.M.; Schrauwen, E.J.A.; Linster, M.; De Graaf, M.; Herfst, S.; Fouchier, R.A.M.

2011-01-01

294

Recombination and Transmission Studies with Influenza Virus.  

National Technical Information Service (NTIS)

Transmission of influenza virus infection in mice can be correlated with demonstrable airborne virus in the vicinity of infector mice during the period of their infectiousness; the critical difference that distinguishes transmissible and non-transmissible...

E. D. Kilbourne

1966-01-01

295

Predicting 'airborne' influenza viruses: (trans-) mission impossible?  

PubMed

Repeated transmission of animal influenza viruses to humans has prompted investigation of the viral, host, and environmental factors responsible for transmission via aerosols or respiratory droplets. How do we determine-out of thousands of influenza virus isolates collected in animal surveillance studies each year-which viruses have the potential to become 'airborne', and hence pose a pandemic threat? Here, using knowledge from pandemic, zoonotic and epidemic viruses, we postulate that the minimal requirements for efficient transmission of an animal influenza virus between humans are: efficient virus attachment to (upper) respiratory tissues, replication to high titers in these tissues, and release and aerosolization of single virus particles. Investigating 'airborne' transmission of influenza viruses is key to understand-and predict-influenza pandemics. PMID:22440921

Sorrell, E M; Schrauwen, E J A; Linster, M; De Graaf, M; Herfst, S; Fouchier, R A M

2011-09-03

296

West Nile Virus: Symptoms and Treatment  

MedlinePLUS

... message, please visit this page: About CDC.gov . West Nile Virus Share Compartir Add this to... Añadir en... ... Most people (70-80%) who become infected with West Nile virus do not develop any symptoms. Febrile illness ...

297

Adaptation of Newcastle Virus to Mammals.  

National Technical Information Service (NTIS)

Strain 'T' of the Newcastle virus was adapted to guinea pigs and other mammals. Following the intracerebral inoculation, the adapted virus caused an infection, clinically expressed by signs of central nervous system disease (irritability, anorexia, locomo...

V. N. Syurin

1966-01-01

298

FAQ: West Nile Virus and Dead Birds  

MedlinePLUS

... Digg Google Bookmarks FAQ: West Nile Virus & Dead Birds How do birds get infected with West Nile ... dead bird sightings to local authorities. How do birds get infected with West Nile virus? West Nile ...

299

Differentiation of porcine reproductive and respiratory syndrome virus N protein using a virus-based ELISA.  

PubMed

The bacterially expressed nucleocapsid (N) protein of porcine respiratory and reproductive syndrome virus (PRRSV) was used as immunogen to generate a rabbit-derived polyclonal antibody. The immunoreactivity of the protein to the antibody was confirmed by Western blot analysis. Using PRRSV, transmissible gastroenteritis virus, porcine epidemic diarrhea virus, pseudorabies virus, and avian infectious bronchitis virus as coating antigens, a virus-based ELISA was established. The polyclonal antibody against PRRSV N protein used as a diagnostic agent was capable of differentiating PRRSV from the other viruses. PMID:21529294

Li, Guangxing; Ren, Xiaofeng

2011-04-01

300

The dsRNA viruses.  

PubMed

The dsRNA viruses represent a large, diverse group of pathogens (affecting a very wide range of host species), several of which are of medical, veterinary or agricultural importance. Many of the icosahedral dsRNA viruses show striking structural and functional similarities that reflect the similar problems that they face replicating their dsRNA genomes while avoiding the dsRNA activated defence mechanisms of their host species. These similarities appear to indicate a common if distant ancestry that is not always evident simply by comparison of nucleotide or amino acid sequences. To facilitate the identification and comparisons of cognate proteins from different species, genera and families of dsRNA viruses, a series of tables were originally constructed for the 7th International Symposium of dsRNA viruses held in Aruba in 2000. These have now been updated and extended (for the 8th Symposium, held in Tuscany 2003) and are available from the dsRNA virus website at. PMID:15010213

Mertens, Peter

2004-04-01

301

Why genes overlap in viruses  

PubMed Central

The genomes of most virus species have overlapping genes—two or more proteins coded for by the same nucleotide sequence. Several explanations have been proposed for the evolution of this phenomenon, and we test these by comparing the amount of gene overlap in all known virus species. We conclude that gene overlap is unlikely to have evolved as a way of compressing the genome in response to the harmful effect of mutation because RNA viruses, despite having generally higher mutation rates, have less gene overlap on average than DNA viruses of comparable genome length. However, we do find a negative relationship between overlap proportion and genome length among viruses with icosahedral capsids, but not among those with other capsid types that we consider easier to enlarge in size. Our interpretation is that a physical constraint on genome length by the capsid has led to gene overlap evolving as a mechanism for producing more proteins from the same genome length. We consider that these patterns cannot be explained by other factors, namely the possible roles of overlap in transcription regulation, generating more divergent proteins and the relationship between gene length and genome length.

Chirico, Nicola; Vianelli, Alberto; Belshaw, Robert

2010-01-01

302

Fungal transmission of plant viruses.  

PubMed

Thirty soilborne viruses or virus-like agents are transmitted by five species of fungal vectors. Ten polyhedral viruses, of which nine are in the family Tombusviridae, are acquired in the in vitro manner and do not occur within the resting spores of their vectors, Olpidium brassicae and O. bornovanus. Fungal vectors for other viruses in the family should be sought even though tombusviruses are reputed to be soil transmitted without a vector. Eighteen rod-shaped viruses belonging to the furo- and bymovirus groups and to an unclassified group are acquired in the in vivo manner and survive within the resting spores of their vector, O. brassicae, Polymyxa graminis, P. betae, and Spongospora subterranea. The viral coat protein has an essential role in in vitro transmission. With in vivo transmission a site in the coat protein-read through protein (CP-RT) of beet necrotic yellow vein furovirus determines vector transmissibility as does a site in a similar 98-kDa polyprotein of barley mild mosaic bymovirus. The mechanisms by which virions move (or are moved) into and out of the protoplasm of zoospores or of thalli needs study. PMID:15012536

Campbell, R N

1996-01-01

303

Droplet Microfluidics for Virus Discovery  

NASA Astrophysics Data System (ADS)

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.

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

2012-02-01

304

Viruses and thyroiditis: an update  

PubMed Central

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.

Desailloud, Rachel; Hober, Didier

2009-01-01

305

Serological relationship of the Tacaribe complex of viruses to lymphocytic choriomeningitis virus.  

PubMed

By means of the indirect fluorescent-antibody test, cross serological reactivity was demonstrated between lymphocytic choriomeningitis (LCM) virus and the viruses of the Tacaribe complex. Antisera to all members of the Tacaribe complex reacted with LCM virus; LCM antisera gave significant staining of Amapari virus, but minimal or inconsistent reactions with Tacaribe virus, and no reaction with two other viruses of the Tacaribe complex. A low level cross-reaction was observed in complement fixation tests of Machupo and Pichinde antisera against LCM antigen. Immunization with Tacaribe and Amapari viruses did not protect mice against challenge with LCM virus. Because of the identical appearance of the virions, the sharing of antigens, and the many biological similarities between LCM and the Tacaribe complex viruses, it is proposed that they be considered as constituting a new taxonomic group of viruses. PMID:4985595

Rowe, W P; Pugh, W E; Webb, P A; Peters, C J

1970-03-01

306

Serological Relationship of the Tacaribe Complex of Viruses to Lymphocytic Choriomeningitis Virus  

PubMed Central

By means of the indirect fluorescent-antibody test, cross serological reactivity was demonstrated between lymphocytic choriomeningitis (LCM) virus and the viruses of the Tacaribe complex. Antisera to all members of the Tacaribe complex reacted with LCM virus; LCM antisera gave significant staining of Amapari virus, but minimal or inconsistent reactions with Tacaribe virus, and no reaction with two other viruses of the Tacaribe complex. A low level cross-reaction was observed in complement fixation tests of Machupo and Pichinde antisera against LCM antigen. Immunization with Tacaribe and Amapari viruses did not protect mice against challenge with LCM virus. Because of the identical appearance of the virions, the sharing of antigens, and the many biological similarities between LCM and the Tacaribe complex viruses, it is proposed that they be considered as constituting a new taxonomic group of viruses.

Rowe, Wallace P.; Pugh, Wendell E.; Webb, Patricia A.; Peters, Clarence J.

1970-01-01

307

The wonder world of microbial viruses  

PubMed Central

The first congress on Viruses of Microbes took place at the Institut Pasteur in Paris, France, on 21–25 June 2010. The advances in genomics and metagenomics reported at this meeting reveal striking and unexpected complexity of the virus world. Viruses, in particular viruses that infect prokaryotes and unicellular eukaryotes, are emerging as the most abundant class of biological entities on earth and a major evolutionary and geochemical force.

Koonin, Eugene V

2012-01-01

308

[Pulmonary complications in children with human immunodeficiency virus infection].  

PubMed

Pulmonary complications in children infected by human immunodeficiency virus (HIV) are common and may be the first manifestation of acquired immunodeficiency syndrome (AIDS). The aim of our study was to review pulmonary diseases and complications in pediatric patients with HIV infection in a large tertiary hospital in Santiago, Chile. We performed a retrospective, descriptive analysis of 17 patients with HIV infection controlled at the Hospital Dr. Sótero del Rio. Respiratory complications/diseases were: overall pneumonia (n: 14), recurrent pneumonia (n: 10), citomegalovirus associated pneumonia (n: 4), Pneumocystis jiroveci associated pneumonia (n: 1) pulmonary tuberculosis (n: 1), lymphoid interstitial pneumonia (n: 3) and chronic pulmonary disease (n: 7). Microorganisms isolated were mostly atypical and frequently associated with severe and chronic pulmonary damage. A high degree of suspicion is required to detect atypical microorganisms promptly, in order to rapidly implement pathogen targeted therapy that could potentially decrease the possibility of sequelae. PMID:17728918

Brockmann V, Pablo; Viviani S, Támara; Peña D, Anamaría

2007-08-20

309

Amelioration of Influenza Virus Pathogenesis in Chickens Attributed to the Enhanced Interferon-Inducing Capacity of a Virus with a Truncated NS1 Gene  

Microsoft Academic Search

Avian influenza virus (AIV) A\\/turkey\\/Oregon\\/71-SEPRL (TK\\/OR\\/71-SEPRL) (H7N3) encodes a full-length NS1 protein and is a weak inducer of interferon (IFN). A variant, TK\\/OR\\/71-delNS1 (H7N3), produces a truncated NS1 protein and is a strong inducer of IFN. These otherwise genetically related variants differ 20-fold in their capacities to induce IFN in primary chicken embryo cells but are similar in their sensitivities

Angela N. Cauthen; David E. Swayne; Margaret J. Sekellick; Philip I. Marcus; David L. Suarez

2007-01-01

310

Reassortment of Thogoto Virus (a Tick-borne Influenza-like Virus) in a Vertebrate Host  

Microsoft Academic Search

SUMMARY Reassortment is an important factor in the evolution of segmented genome viruses. For arthropod-borne viruses it is important to determine whether the vertebrate host acts as a site of reassortant virus formation since vertebrates often act as amplifying hosts. Mutants of Thogoto virus, a tick-borne orthomyxo-like virus, were shown to produce wild-type progeny in a dually infected permissive host

LINDA D. JONES; CLIVE R. DAVIES; BERNADETTE M. GREEN; PATRICIA A. NUTTALL

1987-01-01

311

Reverse Genetics of Measles Virus and Resulting Multivalent Recombinant Vaccines: Applications of Recombinant Measles Viruses  

Microsoft Academic Search

An overview is given on the development of technologies to allow reverse genetics of RNA viruses, i.e., the rescue of viruses\\u000a from cDNA, with emphasis on nonsegmented negative-strand RNA viruses ( Mononegavirales ), as exemplified for measles virus\\u000a (MV). Primarily, these technologies allowed site-directed mutagenesis, enabling important insights into a variety of aspects\\u000a of the biology of these viruses. Concomitantly,

M. A. Billeter; H. Y. Naim; S. A. Udem

312

Variation and evolution of plant virus populations  

Microsoft Academic Search

Over the last 15 years, interest in plant virus evolution has re-emerged, as shown by the increasing number of papers published on this subject. In recent times, research in plant virus evolution has been viewed from a molecular, rather than populational, standpoint, and there is a need for work aimed at understanding the processes involved in plant virus evolution. However, accumulated

Fernando García-Arenal; Aurora Fraile; José M. Malpica

2003-01-01

313

Studies with rinderpest virus in tissue culture  

Microsoft Academic Search

Summary The stability of cultured rinderpest virus, in maintenance medium containing 5% normal ox serum, was studied at 4°, 37°, and 56° C. The half-life at these temperatures was calculated and the results compared with figures available for other strains of rinderpest virus in cattle tissues and for measles virus in tissue culture fluids.

W. Plowright; R. D. Ferris

1962-01-01

314

Chimeric Measles Viruses with a Foreign Envelope  

Microsoft Academic Search

Measles virus (MV) and vesicular stomatitis virus (VSV) are both members of the Mononegavirales but are only distantly related. We generated two genetically stable chimeric viruses. In MGV, the reading frames of the MV envelope glycoproteins H and F were substituted by a single reading frame encoding the VSV G glyco- protein; MG\\/FV is similar but encodes a G\\/F hybrid

PIUS SPIELHOFER; THOMAS BACHI; THOMAS FEHR; GUDRUN CHRISTIANSEN; ROBERTO CATTANEO; KARIN KAELIN; MARTIN A. BILLETER; HUSSEIN Y. NAIM

1998-01-01

315

Signal Transduction in Resistance to Plant Viruses  

Microsoft Academic Search

Salicylic acid is part of a signal transduction pathway that induces resistance to viruses, bacteria and fungi. In tobacco and Arabidopsis the defensive signal transduction pathway branches downstream of salicylic acid. One branch induces PR-1 proteins and resistance to bacteria and fungi, while the other triggers induction of resistance to RNA and DNA viruses. This virus-specific branch can be activated

Alex M. Murphy; Androulla Gilliland; Chui Eng Wong; Joanne West; Davinder P. Singh; John P. Carr

2001-01-01

316

Further immunization studies with mammary tumor virus.  

PubMed

A single i.m. dose of formalin-inactivated murine mammary tumor virus greatly reduces viral expression and mammary tumorigenesis in Af (tumor incidence, 39%) and RIIIf (tumor incidence, 11%) mice, which carry only endogenous, gamete-transmitted virus. In C57BL mice, 1 mug of vaccine in Freund's complete adjuvant protects against later challenge with RIII virus. PMID:175938

Charney, J; Holben, J A; Cody, C M; Moore, D H

1976-02-01

317

Beet mosaic virus: epidemiology and damage  

Microsoft Academic Search

Overview:<\\/strong>The aim of the studies described in this thesis was to obtain a thorough understanding of the main factors determining the spread of a potyvirus in a high plant density crop. The factors studied included the relationships between virus, host and vector, the spread of the virus around an initial virus source consisting of one or more infected plants, the

A. N. Dusi

1999-01-01

318

Advances in virus research. Volume 32  

SciTech Connect

This book describes advances in the field of virus research. Topics covered include: Retroid virus genome replication; viral oncogenes, v-yes and kerbB, and their cellular counterparts; hepatitis A; and molecular studies of brome Mosaic virus using infectious transcripts from cloned cDNA.

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

1987-01-01

319

Advances in virus research. Volume 31  

SciTech Connect

This book presents topics in virus research and advances made in this field. Topics covered include: ambisense RNA genomes of arenaviruses and phleboviruses; the molecular basis of antigenic variation in influenza virus; epitope mapping of flavivirus glycoproteins; regulation of adenovirus mRNA formation; regulation of protein synthesis in virus infected animal cells; and antibody-dependent enhancement of vira infectivity.

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

1986-01-01

320

Plant virus taxonomy : some current issues  

Microsoft Academic Search

Summary Classification of viruses is regulated by the International Committee on the Taxonomy of Viruses (ICTV). This organisation provides not only the rules to be applied but has to approve all new names for virus species, genera or higher taxa. Anybody may make a taxonomic proposal but most frequently they are generated by specialist study groups that exist for most

M. J. ADAMS

321

Pathogenesis of Dengue Vaccine Viruses in Mosquitoes.  

National Technical Information Service (NTIS)

The dengue-2 vaccine virus (S-1) and its parent virus (PR-159) were compared for their ability to infect orally, to replicate in, and subsequently to be transmitted by Aedes aegypti mosquitoes. The vaccine virus was markedly less efficient in its ability ...

B. J. Beaty T. H. G. Aitken

1982-01-01

322

Ubiquitous Reassortments in influenza a viruses  

Microsoft Academic Search

Influenza A virus is a negative stranded RNA virus, composed of eight segmented RNA molecules, including polymerases (PB2, PB1, PA), haemaglutin (HA), nucleoprotein (NP), neuraminidase (NA), matrix protein (MP), and nonstructure gene (NS). The influenza A viruses are notorious for rapid mutations, frequent genomic reassortments, and possible recombinations. Among these evolutionary events, genetic reassortments refer to exchanges of internal fragments

Xiu-feng Wan; Mufit Ozden; Guohui Lin

2008-01-01

323

Arctic-like rabies virus, Bangladesh.  

PubMed

Arctic/Arctic-like rabies virus group 2 spread into Bangladesh ?32 years ago. Because rabies is endemic to and a major public health problem in this country, we characterized this virus group. Its glycoprotein has 3 potential N-glycosylation sites that affect viral pathogenesis. Diversity of rabies virus might have public health implications in Bangladesh. PMID:23171512

Jamil, Khondoker Mahbuba; Ahmed, Kamruddin; Hossain, Moazzem; Matsumoto, Takashi; Ali, Mohammad Azmat; Hossain, Sohrab; Hossain, Shakhawat; Islam, Aminul; Nasiruddin, Mohammad; Nishizono, Akira

2012-12-01

324

Role of viruses in human evolution  

Microsoft Academic Search

The study of viral molecular genetics has produced a considerable body of research into the se- quences and phylogenetic relationships of human and an- imal viruses. A review of this literature suggests that humans have been afflicted by viruses throughout their evolutionary history, although the number and types have changed. Some viruses show evidence of long-standing inti- mate relationship and

Linda M. Van Blerkom

2003-01-01

325

RNAi suppressors encoded by pathogenic human viruses  

Microsoft Academic Search

RNA silencing or RNAi interference (RNAi) serves as an innate antiviral mechanism in plants, fungi and animals. Human viruses, like plant viruses, encode suppressor proteins or RNAs that block or modulate the RNAi pathway. This review summarizes the mechanisms by which pathogenic human viruses affect the RNAi pathway. Furthermore, some applications of the viral RNAi suppressor functions and the consequences

Walter de Vries; Ben Berkhout

2008-01-01

326

GENETIC VARIABILITY IN MAIZE CHLOROTIC DWARF VIRUS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Maize chlorotic dwarf virus (MCDV) (genus Waikavirus; family Sequiviridae) is a picorna-like virus transmitted by the black-faced leafhopper, Graminella nigrifrons, in a semi-persistent manner using a virus-encoded helper protein. The MCDV genome contains one large open reading frame encoding a poly...

327

Computer Viruses and Safe Educational Practices.  

ERIC Educational Resources Information Center

|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…

Azarmsa, Reza

1991-01-01

328

Some properties of feline panleukopenia virus  

Microsoft Academic Search

Summary Feline panleukopenia virus was isolated from a peracute, fatal disease in a 3-month-old Burmese kitten by inoculation of a 1 per cent spleen suspension onto freshly seeded cultures of a feline embryo (FEmb) cell line. The virus was assayed by the detection of intranuclear inclusion bodies in stained coverslips of FEmb cells. The virus was not inactivated by ether,

M. J. Studdert; J. E. Peterson

1973-01-01

329

A Classification of Viruses Through Recursion Theorems  

Microsoft Academic Search

We study computer virology from an abstract point of view. Viruses and worms are self-replicating programs, whose constructions are essen- tially based on Kleene's second recursion theorem. We show that we can classify viruses as solutions of fixed point equations which are obtained from dierent versions of Kleene's second recursion theorem. This lead us to consider four classes of viruses

Guillaume Bonfante; Matthieu Kaczmarek; Jean-yves Marion

2007-01-01

330

Virus entry: molecular mechanisms and biomedical applications  

Microsoft Academic Search

Viruses have evolved to enter cells from all three domains of life — Bacteria, Archaea and Eukaryotes. Of more than 3,600 known viruses, hundreds can infect human cells and most of those are associated with disease. To gain access to the cell interior, animal viruses attach to host-cell receptors. Advances in our understanding of how viral entry proteins interact with

Dimiter S. Dimitrov

2004-01-01

331

Persistent rubella virus infection in laboratory animals  

Microsoft Academic Search

Summary Several strains of rubella virus were able to establish a persistent or carrier-type infection in adult hamsters and suckling rabbits. No evidence of rubella virus persistence for prolonged periods was detected in suckling and adult ferrets or in adult rabbits, although serological studies suggested that these animals had been infected with rubella virus.

J. S. Oxford; C. W. Potter

1971-01-01

332

Inhibition of Interferons by Ectromelia Virus  

Microsoft Academic Search

Ectromelia virus (EV) is an orthopoxvirus (OPV) that causes mousepox, a severe disease of laboratory mice. Mousepox is a useful model of OPV infection because EV is likely to be a natural mouse pathogen, unlike its close relatives vaccinia virus (VV) and variola virus. Several studies have highlighted the importance of mouse interferons (IFNs) in resistance to and recovery from

Vincent P. Smith; Antonio Alcami

2002-01-01

333

An Epidemiological View of Worms and Viruses  

Microsoft Academic Search

The communal nature of the Internet exposes organizations and home computer users to a multitude of worms, viruses, and other malicious software (malware) threats such as spyware and Trojan horses. Viruses are program fragments attached to normal programs or files that hijack the execution control of the host program to reproduce copies of the virus. Worms are automated self-replicating programs

Thomas M. Chen

334

ENTOMOPATHOGENIC VIRUS FROM GLASSY-WINGED SHARPSHOOTER  

Technology Transfer Automated Retrieval System (TEKTRAN)

The glassy-winged sharpshooter, GWSS, has been shown to be susceptible to insect virus infections. A new virus was isolated from field caught GWSS and partially sequenced. Sequence identity showed that this was a new sharpshooter virus separate from those already reported by Hunter et. al. 2004, and...

335

Occult hepatitis B virus infection.  

PubMed

Many studies have shown that hepatitis B virus infection may also occur in hepatitis B surface antigen-negative patients. This occult infection has been identified both in patients with cryptogenic liver disease and in patients with hepatitis C virus-related chronic hepatitis, and much evidence suggests that it may be a risk factor of hepatocellular carcinoma development. However several aspects of this occult infection remain unclear such as its prevalence and the factor(s) involved in the lack of circulating hepatitis B surface antigen. Moreover, it is uncertain whether the occult hepatitis B virus infection may contribute to chronic liver damage, considering that it is usually associated with a suppressed viral replication. Evidence and hypotheses concerning this fascinating field of bio-medical research are reviewed. PMID:11215565

Raimondo, G; Balsano, C; Craxì, A; Farinati, F; Levrero, M; Mondelli, M; Pollicino, T; Squadrito, G; Tiribelli, C

2000-12-01

336

[Capping strategies in RNA viruses].  

PubMed

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

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

2012-04-25

337

Viruses & kidney disease: beyond HIV  

PubMed Central

HIV-infected patients may acquire new viral co-infections; they may also experience the reactivation or worsening of existing viral infections, including active, smoldering, or latent infections. HIV-infected patients may be predisposed to these viral infections due to immunodeficiency or to risk factors common to HIV and other viruses. A number of these affect the kidney, either by direct infection or by deposition of immune complexes. In this review we discuss the renal manifestations and treatment of hepatitis C virus, BK virus, adenovirus, cytomegalovirus, and parvovirus B19 in patients with HIV disease. We also discuss an approach to the identification of new viral renal pathogens, using a viral gene chip to identify viral DNA or RNA.

Waldman, Meryl; Marshall, Vickie; Whitby, Denise; Kopp, Jeffrey B.

2008-01-01

338

Treatment of gastrointestinal viruses.  

PubMed

The most common enteric viruses responsible for diarrhoea are rotavirus, enteric adenoviruses, caliciviruses including the Norwalk agent and astrovirus. These infections are usually mild to moderate in severity, self-limiting and of short duration and thus, specific antiviral therapy is not recommended. The standard management of these infections is restoration of fluid and electrolyte balance and then maintenance of hydration until the infection resolves. WHO oral rehydration therapy (ORT) was introduced about 30 years ago and has saved the lives of many infants and young children. During the last 10 years it has become evident that the efficacy of ORT can be increased by reducing the osmolality of the WHO oral rehydration solution (ORS) to produce a relatively hypotonic solution. Hypotonic ORS appears to be safe and effective in all forms of acute diarrhoea in childhood. Complex substrate ORS, which is also usually hypotonic, has been shown to have increased efficacy in cholera but not in other bacterial or viral diarrhoeas. Nevertheless, the scientific rationale for using rice or resistant starch as substrate in ORS is of physiological interest. Other treatments such as hyperimmune bovine colostrum, probiotics and antiviral agents are largely experimental and have not been introduced into routine clinical practice. Cytomegalovirus (CMV) infection of the gastrointestinal tract occurs mainly in the immunocompromised although it has been reported in immunocompetent individuals. CMV infects both the oesophagus and colon to produce oesophagitis, often with discrete ulcers, and colitis, respectively. Both conditions can be treated with ganciclovir or foscarnet. Failure to respond to monotherapy is an indication to use both agents concurrently. PMID:11444033

Farthing, M J

2001-01-01

339

Lagos Bat Virus in Kenya?  

PubMed Central

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.

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

2008-01-01

340

Preventing respiratory syncytial virus infections  

PubMed Central

Respiratory syncytial virus infection is the leading cause of lower respiratory tract infections in young children. Palivizumab, a respiratory syncytial virus-specific monoclonal antibody, reduces the hospitalization rate of high-risk children but it is very costly. This statement replaces three previous position statements from the Canadian Paediatric Society about this topic, and was updated primarily to discuss recent changes in the American Academy of Pediatrics guidelines in the Canadian context. It reviews the published literature and provides recommendations regarding palivizumab use in high-risk children.

Robinson, JL

2011-01-01

341

Neonatal herpes simplex virus infections.  

PubMed

Neonatal herpes simplex virus infections are uncommon, but because of the morbidity and mortality associated with the infection they are often considered in the differential diagnosis of ill neonates. The use of polymerase chain reaction for diagnosis of central nervous system infections and the development of safe and effective antiviral therapy has revolutionized the diagnosis and management of these infants. Initiation of long-term antiviral suppressive therapy in these infants has led to significant improvement in morbidity. This article summarizes the epidemiology of neonatal herpes simplex virus infections and discusses clinical presentation, diagnosis, management, and follow up of infants with neonatal herpes disease. PMID:23481105

Pinninti, Swetha G; Kimberlin, David W

2013-04-01

342

Charting the host adaptation of influenza viruses.  

PubMed

Four influenza pandemics have struck the human population during the last 100 years causing substantial morbidity and mortality. The pandemics were caused by the introduction of a new virus into the human population from an avian or swine host or through the mixing of virus segments from an animal host with a human virus to create a new reassortant subtype virus. Understanding which changes have contributed to the adaptation of the virus to the human host is essential in assessing the pandemic potential of current and future animal viruses. Here, we develop a measure of the level of adaptation of a given virus strain to a particular host. We show that adaptation to the human host has been gradual with a timescale of decades and that none of the virus proteins have yet achieved full adaptation to the selective constraints. When the measure is applied to historical data, our results indicate that the 1918 influenza virus had undergone a period of preadaptation prior to the 1918 pandemic. Yet, ancestral reconstruction of the avian virus that founded the classical swine and 1918 human influenza lineages shows no evidence that this virus was exceptionally preadapted to humans. These results indicate that adaptation to humans occurred following the initial host shift from birds to mammals, including a significant amount prior to 1918. The 2009 pandemic virus seems to have undergone preadaptation to human-like selective constraints during its period of circulation in swine. Ancestral reconstruction along the human virus tree indicates that mutations that have increased the adaptation of the virus have occurred preferentially along the trunk of the tree. The method should be helpful in assessing the potential of current viruses to found future epidemics or pandemics. PMID:21109586

dos Reis, Mario; Tamuri, Asif U; Hay, Alan J; Goldstein, Richard A

2010-11-25

343

Expression of rabies virus glycoprotein from a recombinant vaccinia virus  

Microsoft Academic Search

Rabies is one of the oldest diseases known to man, but its successful control has remained elusive. Although effective vaccines of tissue culture origin against rabies do exist1, such preparations are expensive. Live vaccinia virus (VV) recombinants expressing influenza or hepatitis B antigens have recently been used to immunize against these diseases2-4. We have now used this approach to produce

M. P. Kieny; R. Lathe; R. Drillien; D. Spehner; S. Skory; D. Schmitt; T. Wiktor; H. Koprowski; J. P. Lecocq

1984-01-01

344

Viruses and host evolution: virus-mediated self identity.  

PubMed

Virus evolution has become a topic that involves population based selection. Both quasispecies based populations and reticulated mosaic exchange of populations of genetic elements are now well established. This has led us to the understanding that a cooperative consortia can be a crucial aspect of virus driven evolution. Thus viruses exist in groups that can cooperate. However, consortial based evolution (group selection) has long been dismissed by evolutionary biologist. Recently, biocommunication theory has concluded that the evolution and editing of any code or language requires a consortial based process in order to adhere to pragmatic (context) requirements for meaning (in conflict with survival of the fittest concepts). This has led to the idea that viruses are the natural editors of biological codes or language. In this chapter, I present the view that the persistence of virus information in their host provides a natural process of host code editing that is inherently consortial. Since persistence requires mechanisms to attain stability and preclude competition, it also provided mechanisms that promote group identity. Accordingly, I review the viral origins of addiction modules and how these affect both persistence and group identity. The concepts emerging from addiction module based group identity are then generalized and applied to social identity systems as well. I then examine the prokaryotes and the involvement of viral elements in the emergence of their group identity systems (biofilms). Here, integrating dsDNA agents prevailed. In the eukaryotes, however, a large shift in virus-host evolution occurred in which the role of dsDNA agents was diminished but the role of retroviruses and retroposons was greatly enhanced. These agents provided greatly expanded and network based regulatory complexity that was controlled by sensory inputs. From this perspective, the role of virus in the origin of the adaptive immune system is then outlined. I then consider human evolution from the perspective of the great HERV colonization. The origin of a large social brain able to support the learning of language is presented from this viral perspective. The role of addiction modules in the origin of extended social bonding of humans is outlined and applied to the emergence of language as a system of group identity. PMID:22399381

Villarreal, Luis

2012-01-01

345

A cross-species view on viruses  

PubMed Central

We describe the creative ways that virologists are leveraging experimental cross-species infections to study the interactions between viruses and hosts. While viruses are usually well adapted to their hosts, cross-species approaches involve pairing viruses with species that they don’t naturally infect. These cross-species infections pit viruses against animals, cell lines, or even single genes from foreign species. We highlight examples where cross-species infections have yielded insights into mechanisms of host innate immunity, viral countermeasures, and the evolutionary interplay between viruses and hosts.

Sawyer, Sara L.; Elde, Nels C.

2012-01-01

346

Política de comentarios del NCI  

Cancer.gov

Animamos a los usuarios a compartir sus ideas relacionadas con los temas en discusión en las secciones o foros determinados para tal fin en este sitio web u otros sitios administrados por el Instituto Nacional del Cáncer. Revisamos y publicamos los comentarios de acuerdo a la política indicada a continuación. Nos reservamos el derecho, a nuestra completa discreción, a no publicar o eliminar comentarios que no están de acuerdo con nuestra política.

347

Persistence of virus lipid signatures upon silicification  

NASA Astrophysics Data System (ADS)

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.

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

2011-12-01

348

Method for detecting viruses in aerosols.  

PubMed Central

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

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

1985-01-01

349

SEROLOGICAL STUDIES OF SWINE INFLUENZA VIRUSES  

PubMed Central

1. Cross-neutralization tests with sera from swine recovered from infection with swine influenza indicated the serological identity of 7 strains of swine influenza virus obtained from different sources. 2. Cross-neutralization tests with sera from rabbits, immunized to swine influenza virus, exposed serological differences among the same 7 swine influenza virus strains. Two strains appeared to be serologically similar and were characterized by the ability to produce effective homologous virus-neutralizing sera which were, however, poor or ineffective against the heterologous virus strains. Two other strains were also serologically similar but produced antibodies effective not only against themselves, but against all heterologous strains as well. The remaining 3 strains were intermediate in their ability to produce heterologous virus-neutralizing antibodies. 3. The human influenza viruses included, especially strains WS and Oakham, were most effectively differentiated serologically from the swine influenza viruses by rabbit antisera. 4. The suggestion is advanced that swine antisera express the antigenic composition of the swine influenza viruses, while rabbit antisera reflect either their antigenic arrangement or the arrangement of the components responsible for their mouse pathogenicity. On this interpretation the 7 strains of swine influenza virus studied would be considered to have similar antigenic compositions but differing antigenic structures. 5. The serological differences among strains of the swine influenza virus, detectible by rabbit antisera, are probably of no practical significance so far as the natural disease, swine influenza, is concerned.

Shope, Richard E.

1939-01-01

350

Expanding networks of RNA virus evolution  

PubMed Central

In a recent BMC Evolutionary Biology article, Huiquan Liu and colleagues report two new genomes of double-stranded RNA (dsRNA) viruses from fungi and use these as a springboard to perform an extensive phylogenomic analysis of dsRNA viruses. The results support the old scenario of polyphyletic origin of dsRNA viruses from different groups of positive-strand RNA viruses and additionally reveal extensive horizontal gene transfer between diverse viruses consistent with the network-like rather than tree-like mode of viral evolution. Together with the unexpected discoveries of the first putative archaeal RNA virus and a RNA-DNA virus hybrid, this work shows that RNA viral genomics has major surprises to deliver. See research article: http://www.biomedcentral.com/1471-2148/12/91

2012-01-01

351

Virus-Induced Aggregates in Infected Cells  

PubMed Central

During infection, many viruses induce cellular remodeling, resulting in the formation of insoluble aggregates/inclusions, usually containing viral structural proteins. Identification of aggregates has become a useful diagnostic tool for certain viral infections. There is wide variety of viral aggregates, which differ by their location, size, content and putative function. The role of aggregation in the context of a specific virus is often poorly understood, especially in the case of plant viruses. The aggregates are utilized by viruses to house a large complex of proteins of both viral and host origin to promote virus replication, translation, intra- and intercellular transportation. Aggregated structures may protect viral functional complexes from the cellular degradation machinery. Alternatively, the activation of host defense mechanisms may involve sequestration of virus components in aggregates, followed by their neutralization as toxic for the host cell. The diversity of virus-induced aggregates in mammalian and plant cells is the subject of this review.

Moshe, Adi; Gorovits, Rena

2012-01-01

352

Virus-induced aggregates in infected cells.  

PubMed

During infection, many viruses induce cellular remodeling, resulting in the formation of insoluble aggregates/inclusions, usually containing viral structural proteins. Identification of aggregates has become a useful diagnostic tool for certain viral infections. There is wide variety of viral aggregates, which differ by their location, size, content and putative function. The role of aggregation in the context of a specific virus is often poorly understood, especially in the case of plant viruses. The aggregates are utilized by viruses to house a large complex of proteins of both viral and host origin to promote virus replication, translation, intra- and intercellular transportation. Aggregated structures may protect viral functional complexes from the cellular degradation machinery. Alternatively, the activation of host defense mechanisms may involve sequestration of virus components in aggregates, followed by their neutralization as toxic for the host cell. The diversity of virus-induced aggregates in mammalian and plant cells is the subject of this review. PMID:23202461

Moshe, Adi; Gorovits, Rena

2012-10-17

353

Determination of Virus Abundance in Marine Sediments  

PubMed Central

In this study, we optimized procedures to enumerate viruses from marine sediments by epifluorescence microscopy using SYBR Green I as a stain. The highest virus yields from the bulk of the sediments were obtained by utilizing pyrophosphate and 3 min of sonication. The efficiency of extraction benthic viruses by pyrophosphate-ultrasound treatment was about 60% of the extractable virus particles. Samples treated with nucleases had increased virus counts, suggesting a masking effect of extracellular DNA. No significant differences were observed between virus counts obtained by epifluorescence microscopy and transmission electron microscopy. Both formaldehyde and glutaraldehyde gave significant reductions of virus counts after only 24 h of sediment storage, but no further loss occurred after 7 days.

Danovaro, R.; Dell'Anno, A.; Trucco, A.; Serresi, M.; Vanucci, S.

2001-01-01

354

Viruses and prions of Saccharomyces cerevisiae.  

PubMed

Saccharomyces cerevisiae has been a key experimental organism for the study of infectious diseases, including dsRNA viruses, ssRNA viruses, and prions. Studies of the mechanisms of virus and prion replication, virus structure, and structure of the amyloid filaments that are the basis of yeast prions have been at the forefront of such studies in these classes of infectious entities. Yeast has been particularly useful in defining the interactions of the infectious elements with cellular components: chromosomally encoded proteins necessary for blocking the propagation of the viruses and prions, and proteins involved in the expression of viral components. Here, we emphasize the L-A dsRNA virus and its killer-toxin-encoding satellites, the 20S and 23S ssRNA naked viruses, and the several infectious proteins (prions) of yeast. PMID:23498901

Wickner, Reed B; Fujimura, Tsutomu; Esteban, Rosa

2013-01-01

355

Neutrophil uptake of vaccinia virus in vitro  

SciTech Connect

We studied human neutrophils for uptake of vaccinia virus. Uptake was determined radiometrically and by electron microscopy. Vaccinia virus was labeled with /sup 14/C or /sup 3/H, incubated with neutrophils, and quantified in neutrophil pellets in a new radiometric phagocytosis assay. Better results were obtained from assays of (/sup 3/H)thymidine-labeled virus; uptake increased through 1 hr and then plateaued. Phagocytosis of 3H-labeled Staphylococcus aureus was normal. Uptake of virus was serum dependent. Hexose monophosphate shunt activity was measured by two methods. No /sup 14/CO/sub 2/ from (/sup 14/C)1-glucose accompanied uptake of vaccinia virus, in contrast to the respiratory burst accompanying bacterial phagocytosis. Electron microscopy showed intact to slightly digested intraphagolysosomal vaccinia virus. Pock reduction assay showed a decrease in viral content due to neutrophils until 6 hr of incubation, when a modest but significant increase was observed. Thus, neutrophil uptake of vaccinia virus is distinguished from bacterial phagocytosis.

West, B.C.; Eschete, M.L.; Cox, M.E.; King, J.W.

1987-10-01

356

Emerging infectious diseases associated with bat viruses.  

PubMed

Bats play important roles as pollen disseminators and pest predators. However, recent interest has focused on their role as natural reservoirs of pathogens associated with emerging infectious diseases. Prior to the outbreak of severe acute respiratory syndrome (SARS), about 60 bat virus species had been reported. The number of identified bat viruses has dramatically increased since the initial SARS outbreak, and most are putative novel virus species or genotypes. Serious infectious diseases caused by previously identified bat viruses continue to emerge throughout in Asia, Australia, Africa and America. Intriguingly, bats infected by these different viruses seldom display clinical symptoms of illness. The pathogenesis and potential threat of bat-borne viruses to public health remains largely unknown. This review provides a brief overview of bat viruses associated with emerging human infectious diseases. PMID:23917838

Shi, ZhengLi

2013-08-07

357

VIRUS DISEASES OF ORNAMENTAL HIBISCUS  

Technology Transfer Automated Retrieval System (TEKTRAN)

The diagnosis of virus diseases of ornamental hibiscus or shoe flower, Hibiscus rosa-sinensis and H. hybrid, was conducted using tissue blot immunoassay techniques. Reverse transcription-polymerase chain reaction was used to amplify the viral coat protein (CP) gene from infected hibiscus and its nu...

358

Reflections on viruses and cancer  

Microsoft Academic Search

In recent years human and animal cancers have increasingly been shown to have a viral component in their aetiology. Oncogenic viruses will continue to be discovered although with certain cancers there is also an important environmental component, and with others — congenital cancers and cancers of early childhood — an important genetic component. There is thus the probability that ‘cancer’

C. Darcel

1994-01-01

359

Powassan Virus Encephalitis, Minnesota, USA  

PubMed Central

Powassan virus (POWV) is a rare tick-borne agent of encephalitis in North America. Historically, confirmed cases occurred mainly in the northeastern United States. Since 2008, confirmed cases in Minnesota and Wisconsin have increased. We report a fatal case of POWV encephalitis in Minnesota. POWV infection should be suspected in tick-exposed patients with viral encephalitis.

Sonnesyn, Steven

2012-01-01

360

Powassan virus encephalitis, Minnesota, USA.  

PubMed

Powassan virus (POWV) is a rare tick-borne agent of encephalitis in North America. Historically, confirmed cases occurred mainly in the northeastern United States. Since 2008, confirmed cases in Minnesota and Wisconsin have increased. We report a fatal case of POWV encephalitis in Minnesota. POWV infection should be suspected in tick-exposed patients with viral encephalitis. PMID:23017222

Birge, Justin; Sonnesyn, Steven

2012-10-01

361

Ecological Studies on Amapari Virus.  

National Technical Information Service (NTIS)

(1) Amapari virus has been isolated from only two of the many species of rodents and other vertebrates studied at Serra do Navio, Amapa, Brazil. These are Oryzomys capito goeldii and Neacomys guianae. The isolation rate for each species over 4 years was c...

F. P. Pinheiro J. P. Woodall

1969-01-01

362

Who Let the Virus In?  

NSDL National Science Digital Library

Fifty-second monthly installment of our "What A Year!" website project, introducing life science breakthroughs to middle and high school students and their teachers. Respiratory syncytial virus, RSV for short, is so common that almost every child in the United States under two years of age has been infected once, and that half of children under three have been infected at least twice.

2011-11-01

363

A virus-based biocatalyst  

NASA Astrophysics Data System (ADS)

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.

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

364

Viruses as Quasispecies: Biological Implications  

Microsoft Academic Search

During viral infections, the complex and dynamic distributions of variants, termed viral quasispecies, play a key role in the adaptability of viruses to changing environments and the fate of the population as a whole. Mutant spectra are continuously and avoidably generated during RNA genome replication, and they are not just a by-product of error-prone replication, devoid of biological relevance. On

E. Domingo; V. Martín; C. Perales; A. Grande-Pérez; J. García-Arriaza; A. Arias

365

West Nile Virus and Wildlife  

NSDL National Science Digital Library

This peer-reviewed resource from BioScience is about West Nile virus in wildlife. 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.

PETER P. MARRA, SEAN GRIFFING, CAROLEE CAFFREY, A. MARM KILPATRICK, ROBERT McLEAN, CHRISTOPHER BRAND, EMI SAITO, ALAN P. DUPUIS, LAURA KRAMER, and ROBERT NOVAK (;)

2004-05-01

366

Classifying Hepatitis B Virus Genotypes  

Microsoft Academic Search

In 1988, hepatitis B virus (HBV) was classified into four genotypes by a sequence divergence in the entire genome exceeding 8%, and designated by capital letters of the alphabet from A to D. There are seven genotypes of HBV (A–G) at present, and an eighth is on the horizon. They have an uneven geographical distribution, and only a few of

Yuzo Miyakawa; Masashi Mizokami

2003-01-01

367

Recombination in Hepatitis C Virus  

PubMed Central

Hepatitis C virus (HCV) is a Flavivirus with a positive-sense, single-stranded RNA genome of about 9,600 nucleotides. It is a major cause of liver disease, infecting almost 200 million people all over the world. Similarly to most RNA viruses, HCV displays very high levels of genetic diversity which have been used to differentiate six major genotypes and about 80 subtypes. Although the different genotypes and subtypes share basic biological and pathogenic features they differ in clinical outcomes, response to treatment and epidemiology. The first HCV recombinant strain, in which different genome segments derived from parentals of different genotypes, was described in St. Petersburg (Russia) in 2002. Since then, there have been only a few more than a dozen reports including descriptions of HCV recombinants at all levels: between genotypes, between subtypes of the same genotype and even between strains of the same subtype. Here, we review the literature considering the reasons underlying the difficulties for unequivocally establishing recombination in this virus along with the analytical methods necessary to do it. Finally, we analyze the potential consequences, especially in clinical practice, of HCV recombination in light of the coming new therapeutic approaches against this virus.

Gonzalez-Candelas, Fernando; Lopez-Labrador, F. Xavier; Bracho, Maria Alma

2011-01-01

368

West Nile Virus Research Continues  

Microsoft Academic Search

t was the summer of 2002 and the West Nile Virus (WNV) was making its inexorable journey across the United States. The equine population had already been devastated and there were reports of neurological disease and death in camelids, but no one really knew what the risk was to alpacas and llamas. The Alpaca Research Foundation (ARF) Board of Directors

Michelle Anne Kutzler

369

Autoimmunity in Dengue Virus Infection  

Microsoft Academic Search

Dengue haemorrhagic fever (DHF) is a complicated disease associated with viral and immune pathogenesis. There is still no effective vaccine to prevent the progression of DHF because of its undefined pathogenic mechanisms. The generation of autoimmunity in dengue virus (DEN) infection has been implicated in dengue pathogenesis. Based on our previous studies showing antibodies (Abs) against DEN nonstructural protein 1

Chiou-Feng Lin; Huan-Yao Lei; Ching-Chuan Liu; Hsiao-Sheng Liu; Trai-Ming Yeh; Shun-Hua Chen; Yee-Shin Lin

2004-01-01

370

Nonpathogenic Simian Immunodeficiency Virus Infections  

PubMed Central

The simian immunodeficiency viruses (SIVs) are a diverse group of viruses that naturally infect a wide range of African primates, including African green monkeys (AGMs) and sooty mangabey monkeys (SMs). Although natural infection is widespread in feral populations of AGMs and SMs, this infection generally does not result in immunodeficiency. However, experimental inoculation of Asian macaques results in an immunodeficiency syndrome remarkably similar to human AIDS. Thus, natural nonprogressive SIV infections appear to represent an evolutionary adaptation between these animals and their primate lentiviruses. Curiously, these animals maintain robust virus replication but have evolved strategies to avoid disease progression. Adaptations observed in these primates include phenotypic changes to CD4+ T cells, limited chronic immune activation, and altered mucosal immunity. It is probable that these animals have achieved a unique balance between T-cell renewal and proliferation and loss through activation-induced apoptosis, and virus-induced cell death. A clearer understanding of the mechanisms underlying the lack of disease progression in natural hosts for SIV infection should therefore yield insights into the pathogenesis of AIDS and may inform vaccine design.

Klatt, Nichole R.; Silvestri, Guido; Hirsch, Vanessa

2012-01-01

371

Antigenic variants of rabies virus  

Microsoft Academic Search

Rabies viruses isolated from different animal species in various parts of the world were in the past considered to be antigenically closely related. Only when the antibodies produced in animals immunized with whole virions or viral components were assayed by the plaque reduction method, were some minor differences detected in the antigenic composition of various rabies strains (1). On the

T. J. WIKTOR; H. KOPROWSKI

1980-01-01

372

Mayaro Fever Virus, Brazilian Amazon  

PubMed Central

In February 2008, a Mayaro fever virus (MAYV) outbreak occurred in a settlement in Santa Barbara municipality, northern Brazil. Patients had rash, fever, and severe arthralgia lasting up to 7 days. Immunoglobulin M against MAYV was detected by ELISA in 36 persons; 3 MAYV isolates sequenced were characterized as genotype D.

Azevedo, Raimunda S.S.; Silva, Eliana V.P.; Carvalho, Valeria L.; Rodrigues, Sueli G.; Neto, Joaquim P. Nunes; Monteiro, Hamilton A.O.; Peixoto, Victor S.; Chiang, Jannifer O.; Nunes, Marcio R.T.

2009-01-01

373

Elimination of Protease Activity Restores Efficient Virion Production to a Human Immunodeficiency Virus Type 1 Nucleocapsid Deletion Mutant  

PubMed Central

The nucleocapsid (NC) region of human immunodeficiency virus type 1 (HIV-1) Gag is required for specific genomic RNA packaging. To determine if NC is absolutely required for virion formation, we deleted all but seven amino acids from NC in a full-length NL4-3 proviral clone. This construct, DelNC, produced approximately four- to sixfold fewer virions than did the wild type, and these virions were noninfectious (less than 10?6 relative to the wild type) and severely genomic RNA deficient. Immunoblot and high-pressure liquid chromatography analyses showed that all of the mature Gag proteins except NC were present in the mutant virion preparations, although there was a modest decrease in Gag processing. DelNC virions had lower densities and were more heterogeneous than wild-type particles, consistent with a defect in the interaction assembly or I domain. Electron microscopy showed that the DelNC virions displayed a variety of aberrant morphological forms. Inactivating the protease activity of DelNC by mutation or protease inhibitor treatment restored virion production to wild-type levels. DelNC-protease mutants formed immature-appearing particles that were as dense as wild-type virions without incorporating genomic RNA. Therefore, protease activity combined with the absence of NC causes the defect in DelNC virion production, suggesting that premature processing of Gag during assembly causes this effect. These results show that HIV-1 can form particles efficiently without NC.

Ott, David E.; Coren, Lori V.; Chertova, Elena N.; Gagliardi, Tracy D.; Nagashima, Kunio; Sowder II, Raymond C.; Poon, Dexter T. K.; Gorelick, Robert J.

2003-01-01

374

Restricted Expression of Retrovirus Nucleic Acids and Proteins in Primate Type C Virus (Gibbon Ape Leukemia Virus-Simian Sarcoma Virus)-initiated Human B-Lymphoblast Cultures  

Microsoft Academic Search

Fresh human B-lymphoblasts established in culture following exposure of adult peripheral blood leukocytes to type C retro- viruses of the simian sarcoma virus\\/simian sarcoma-associ ated virus-gibbon ape leukemia virus group were analyzed in detail for the presence of the infecting virus. Viral expression ranged from production of low levels of intact virus in a few cultures to the presence of

P. D. Markham; F. W. Ruscelli; V. S. Kalyanaraman; L. Ceccherini-Nelli; N. R. Miller; M. S. Reitz; S. Z. Salahuddin; R. C. Gallo

375

Common Themes of Antibody Maturation to Simian Immunodeficiency Virus, Simian-Human Immunodeficiency Virus, and Human Immunodeficiency Virus Type 1 Infections  

Microsoft Academic Search

Characterization of virus-specific immune responses to human immunodeficiency virus type 1 (HIV-1) and simian immunodeficiency virus (SIV) is important to understanding the early virus-host interactions that may determine the course of virus infection and disease. Using a comprehensive panel of serological assays, we have previously demonstrated a complex and lengthy maturation of virus-specific antibody responses elicited by attenuated strains of

KELLY STEFANO COLE; MICHAEL MURPHEY-CORB; OPENDRA NARAYAN; SANJAY V. JOAG; GEORGE M. SHAW; RONALD C. MONTELARO; Marion Merrell Dow

1998-01-01

376

Replication of Semliki Forest virus.  

PubMed

Replication of Semliki Forest virus, a typical alphavirus, takes place in the cytoplasm of many eukaryotic cells. The virus genome, the 42 S RNA, directs the synthesis of at least two RNA-dependent RNA polymerases. By the aid of these enzymes complementary 45 S RNA is synthesized; it serves as a template for the synthesis of positive RNA strands with sedimentation values of 45 S and 26 S. In BHK cells close to 200,000 molecules of each RNA species are produced per cell. Both 26 S and 42 S RNAs are associated with polysomes synthesizing viral structural proteins. The 26 S RNA is a duplication of the nucleotide sequences coding for the virion proteins. These are translated as a polyprotein with the capsid protein at the N-terminal end followed by the envelope proteins E2 and E1. Usually only small amounts of nonstructural proteins are synthesized at the exponential phase of virus growth, indicating that a translational control operates in Semliki Forest virus-infected cells. One of our temperature-sensitive mutants, ts-1, directs, however, the synthesis of two nonstructural proteins with MWs of 78,000 and 86,000 when grown at the nonpermissive temperature. The assembly of the viral nucleocapsid begins by association of the capsid protein with the 42 S RNA, which is still serving as a messenger. In this process a cytoplasmic structure sedimenting at about 65 S is presumably one of the capsid protein donors. The 140 S nucleocapsid buds through the host cell plasma membrane whereby the capsid protein interacts with the envelope proteins creating a specific viral envelope devoid of host proteins. Altogether 5,000 to 20,000 virus particles are released from each cell by the end of the growth cycle, representing about 10% of the 42 S RNA molecules synthesized during the infection. PMID:1107685

Kääriäinen, L; Keränen, S; Lachmi, B; Söderlund, H; Tuomi, K; Ulmanen, I

1975-10-01

377

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

PubMed Central

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.

Jahrling, Peter B.

2010-01-01

378

DelPhi: a comprehensive suite for DelPhi software and associated resources  

PubMed Central

Background Accurate modeling of electrostatic potential and corresponding energies becomes increasingly important for understanding properties of biological macromolecules and their complexes. However, this is not an easy task due to the irregular shape of biological entities and the presence of water and mobile ions. Results Here we report a comprehensive suite for the well-known Poisson-Boltzmann solver, DelPhi, enriched with additional features to facilitate DelPhi usage. The suite allows for easy download of both DelPhi executable files and source code along with a makefile for local installations. The users can obtain the DelPhi manual and parameter files required for the corresponding investigation. Non-experienced researchers can download examples containing all necessary data to carry out DelPhi runs on a set of selected examples illustrating various DelPhi features and demonstrating DelPhi’s accuracy against analytical solutions. Conclusions DelPhi suite offers not only the DelPhi executable and sources files, examples and parameter files, but also provides links to third party developed resources either utilizing DelPhi or providing plugins for DelPhi. In addition, the users and developers are offered a forum to share ideas, resolve issues, report bugs and seek help with respect to the DelPhi package. The resource is available free of charge for academic users from URL: http://compbio.clemson.edu/DelPhi.php.

2012-01-01

379

Cross-protection between Tacaribe complex viruses. Presence of neutralizing antibodies against Junin virus (Argentine hemorrhagic fever) in guinea pigs infected with Tacaribe virus.  

PubMed

Cross-protection between Junin virus and five other Tacaribe complex viruses and the serological response of guinea pigs inoculated with Tacaribe virus are reported here. Previous infection with Tamiami or Pichinde viruses significantly delayed guinea pig deaths. A 58% survival rate was found among animals immunized with three doses of Amapari virus, while guinea pigs inoculated with one dose of Machupo or Tacaribe virus were fully protected against Junin virus. Neutralization tests performed in serum samples of guinea pigs immunized with five doses of Tacaribe virus showed that they developed monologous and heterologous neutralizing antibodies. PMID:178627

Weissenbacher, M C; Coto, C E; Calello, M A

380

AISLAMIENTO, IDENTIFICACIÓN Y CARACTERIZACIÓN PARCIAL DE LAS PROPIEDADES PROBIÓTICAS DE CEPAS DE Lactobacillus sp. PROCEDENTES DEL TRACTO GASTROINTESTINAL DE POLLOS DE CEBA ISOLATION, IDENTIFICATION AND PARTIAL CHARACTERIZATION OF THE PROBIOTIC PROPERTIES OF Lactobacillus sp. STRAINS OBTAINED FROM THE GASTROINTESTINAL TRACT OF BROILERS  

Microsoft Academic Search

Isolation of different strains of Lactobacillus sp. from the gastrointestinal tract (GIT) of broilers was carried out aiming to make a preliminary selection and identification of those strains which could resist the main natural barriers in the digestive flow: acid pH (pH 2) and bile salts (1.5 g L of Ox-biles). As result, 20 strains with probiotic activity potential were

A. J. Rondón; L. M. Samaniego; R. Bocourt; S. Rodríguez; G. Milián; M. J. Ranilla; M. Laurencio; M. Pérez

2008-01-01

381

Managing diseases caused by viruses, viroids, and phytoplasmas  

Technology Transfer Automated Retrieval System (TEKTRAN)

Plant viruses and virus-like pathogens are of considerable economic importance in potato production. The plant viruses and viroids are small, noncellular pathogens. In contrast, phytoplasmas are cellular organisms. In this chapter, information is presented on a number of virus and virus-like pat...

382

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...

383

Intrinsic interference between swine influenza and fowl plague virus  

Microsoft Academic Search

Summary Multiplication of swine influenza (SW) virus is inhibited by fowl plague virus (FPV) at the level of RNA synthesis when host cells are infected with both viruses at a high multiplicity of infection. Under these conditions reassortment between the two viruses cannot be detected. The inhibitory effect of FPV is highly reduced and recombinants between the two viruses could

R. Rott; M. Orlich; C. Scholtissek

1981-01-01

384

Influenza virus RNA structure: unique and common features.  

PubMed

The influenza A virus genome consists of eight negative-sense RNA segments. Here we review the currently available data on structure-function relationships in influenza virus RNAs. Various ideas and hypotheses about the roles of influenza virus RNA folding in the virus replication are also discussed in relation to other viruses. PMID:20923332

Gultyaev, Alexander P; Fouchier, Ron A M; Olsthoorn, René C L

2010-10-05

385

Selective Phosphorylation of Antiviral Drugs by Vaccinia Virus Thymidine Kinase  

Microsoft Academic Search

The antiviral activity of a new series of thymidine analogs was determined against vaccinia virus (VV), cowpox virus (CV), herpes simplex virus, and varicella-zoster virus. Several compounds were identified that had good activity against each of the viruses, including a set of novel 5-substituted deoxyuridine analogs. To investigate the possibility that these drugs might be phosphorylated preferentially by the viral

Emma Harden; Kathy A. Keith; Mary P. Johnson; Alexis McBrayer; Ming Luo; Shihong Qiu; Debasish Chattopadhyay; Xuesen Fan; Paul Torrence; Earl Kern; Mark Prichard

2007-01-01

386

Modeling the dynamics of virus shedding into the saliva of Epstein-Barr virus positive individuals  

PubMed Central

Epstein-Barr virus (EBV) can infect both B cells and epithelial cells. Infection of B cells enables the virus to persist within a host while infection of epithelial cells is suggested to amplify viral output. Data from a recent study have shown that the virus shedding in EBV positive individuals is relatively stable over short periods of time but varies significantly over long periods. The mechanisms underlying the regulation of virus shedding within a host are not fully understood. In this paper, we construct a model of ordinary differential equations to study the dynamics of virus shedding into the saliva of infected hosts. Infection of epithelial cells is further separated into infection by virus released from B cells and virus released from epithelial cells. We use the model to investigate whether the long-term variation and short-term stability of virus shedding can be generated by three possible factors: stochastic variations in the number of epithelial cells susceptible to virus released from infected B cells, to virus released from infected epithelial cells, or random variation in the probability that CD8+ T cells encounter and successfully kill infected cells. The results support all three factors to explain the long-term variation but only the first and third factors to explain the short-term stability of virus shedding into saliva. Our analysis also shows that clearance of virus shedding is possible only when there is no virus reactivation from B cells.

Huynh, Giao T; Rong, Libin

2012-01-01

387

The modulation of apoptosis by oncogenic viruses  

PubMed Central

Transforming viruses can change a normal cell into a cancer cell during their normal life cycle. Persistent infections with these viruses have been recognized to cause some types of cancer. These viruses have been implicated in the modulation of various biological processes, such as proliferation, differentiation and apoptosis. The study of infections caused by oncogenic viruses had helped in our understanding of several mechanisms that regulate cell growth, as well as the molecular alterations leading to cancer. Therefore, transforming viruses provide models of study that have enabled the advances in cancer research. Viruses with transforming abilities, include different members of the Human Papillomavirus (HPV) family, Hepatitis C virus (HCV), Human T-cell Leukemia virus (HTLV-1), Epstein Barr virus (EBV) and Kaposi’s Sarcoma Herpesvirus (KSHV). Apoptosis, or programmed cell death, is a tightly regulated process that plays an important role in development and homeostasis. Additionally, it functions as an antiviral defense mechanism. The deregulation of apoptosis has been implicated in the etiology of diverse diseases, including cancer. Oncogenic viruses employ different mechanisms to inhibit the apoptotic process, allowing the propagation of infected and damaged cells. During this process, some viral proteins are able to evade the immune system, while others can directly interact with the caspases involved in apoptotic signaling. In some instances, viral proteins can also promote apoptosis, which may be necessary for an accurate regulation of the initial stages of infection.

2013-01-01

388

The modulation of apoptosis by oncogenic viruses.  

PubMed

Transforming viruses can change a normal cell into a cancer cell during their normal life cycle. Persistent infections with these viruses have been recognized to cause some types of cancer. These viruses have been implicated in the modulation of various biological processes, such as proliferation, differentiation and apoptosis. The study of infections caused by oncogenic viruses had helped in our understanding of several mechanisms that regulate cell growth, as well as the molecular alterations leading to cancer. Therefore, transforming viruses provide models of study that have enabled the advances in cancer research. Viruses with transforming abilities, include different members of the Human Papillomavirus (HPV) family, Hepatitis C virus (HCV), Human T-cell Leukemia virus (HTLV-1), Epstein Barr virus (EBV) and Kaposi's Sarcoma Herpesvirus (KSHV).Apoptosis, or programmed cell death, is a tightly regulated process that plays an important role in development and homeostasis. Additionally, it functions as an antiviral defense mechanism. The deregulation of apoptosis has been implicated in the etiology of diverse diseases, including cancer. Oncogenic viruses employ different mechanisms to inhibit the apoptotic process, allowing the propagation of infected and damaged cells. During this process, some viral proteins are able to evade the immune system, while others can directly interact with the caspases involved in apoptotic signaling. In some instances, viral proteins can also promote apoptosis, which may be necessary for an accurate regulation of the initial stages of infection. PMID:23741982

Fuentes-González, Alma Mariana; Contreras-Paredes, Adriana; Manzo-Merino, Joaquín; Lizano, Marcela

2013-06-06

389

Pheasant virus: new class of ribodeoxyvirus.  

PubMed

Cocultivation of cells derived from embryos of golden pheasants or Amherst pheasants with chicken embryo cells infected with Bryan strain of Rous sarcoma virus resulted in the detection of viruses which appear to be endogenous in these pheasant cells. The pheasant viruses (PV) were similar to avian leukosis-sarcoma viruses (ALSV) in their gross morphology, in the size of their RNA, in the presence of a virion-associated RNA-dependent DNA polymerase (DNA nucleotidyltransferase; deoxynucleoside triphosphate: DNA deoxynucleotidyltransferase; EC 2.7.7.7), and in their growth characteristics. PV also serves as a helper for the glycoprotein-defective Rous sarcoma virus. However, PV was shown to be different from both ALSV and reticuloendotheliosis virus in the following properties: (i) PV does not have ALSV group specific antigens; (ii) the protein composition of PV is different from those of the other two groups of viruses; (iii) PV fails to complement the defective polymerase of alpha type Rous sarcoma virus; and (iv) PV RNA shows no detectable homology with nucleic acids of the other two groups of viruses. Thus, PV appears to be a new class of RNA viruses which contain RNA-dependent DNA polymerase. PMID:57621

Hanafusa, T; Hanafusa, H; Metroka, C E; Hayward, W S; Rettenmier, C W; Sawyer, R C; Dougherty, R M; Distefano, H S

1976-04-01

390

IMMUNIZATION EXPERIMENTS WITH SWINE INFLUENZA VIRUS  

PubMed Central

1. Swine influenza virus obtained from the lungs of infected ferrets or mice, when administered intramuscularly or subcutaneously, immunizes swine to swine influenza. 2. Ferrets, which have received subcutaneous injections of swine influenza virus obtained from the lungs of infected ferrets, are immune to intranasal infection with this virus. Similar injections with virus from the lungs of infected mice or swine do not immunize. 3. Mice can be immunized to intranasal infection with swine influenza virus by the subcutaneous injection of virus obtained from the lungs of infected mice, but not by similar injection with virus from the lungs of infected ferrets or swine. Repeated injections induce greater immunity than a single one. 4. Intraperitoneal inoculation of both mice and ferrets with swine influenza virus immunizes them to intranasal infection and it appears to make little or no difference whether the virus used as vaccine is obtained from the lungs of infected mice, ferrets, or swine. 5. Field experiments in which swine influenza followed the intramuscular administration of virus are cited as examples of the hazard involved in the use of this means of immunization in a densely crowded susceptible population.

Shope, Richard E.

1936-01-01

391

THE LEECH AS A POTENTIAL VIRUS RESERVOIR  

PubMed Central

Leeches, fed on swine infected with hog cholera, contained virus for as long as 87 days after their infective blood meals. In three instances, infected leeches apparently transmitted hog cholera virus to susceptible swine in the process of normal feeding. Myxoma virus persisted in leeches for as long as 154 days after the ingestion of a blood meal from rabbits with myxomatosis. Leeches fed consecutively, first on swine with hog cholera, and later on rabbits with myxomatosis, acquired both viruses. In such dually infected leeches, the hog cholera virus persisted for as long as 122 days and the myxoma virus for as long as 110 days, the longest periods tested. Leeches fed consecutively, first on rabbits with myxomatosis, and later on swine with hog cholera, acquired only the myxoma virus. Hog cholera virus could not be demonstrated in such dually fed leeches. Myxoma and hog cholera viruses appeared to be present in about equivalent amounts in the anterior and posterior thirds of the bodies of infected leeches. Myxoma and hog cholera viruses were present in the bloody gut contents of infected leeches but were not demonstrable in the body tissues of these leeches. It seems from the findings presented that leeches are not biological carriers of either myxoma or hog cholera virus but instead carry these two agents mechanically in their gastrointestinal tracts. In doing this, they appear to protect the viruses from various deleterious chemical and physical influences to which they would have been exposed in the open. It is speculated that leeches could play a role in nature in perpetuating the blood-borne viruses of certain diseases in which close association with bodies of fresh water is of epidemiological importance.

Shope, Richard E.

1957-01-01

392

Ayuda para usar el sitio web en español del Instituto Nacional del Cáncer  

Cancer.gov

Página de guía que le permite al lector entender la forma en que está organizado el sitio web del Instituto Nacional del Cáncer (NCI), las categorías de información disponibles y las políticas que rigen este sitio web.

393

Characterization of a Replication-Defective Human Immunodeficiency Virus Type 1 att Site Mutant That Is Blocked after the 3? Processing Step of Retroviral Integration  

PubMed Central

Two activities of retroviral integrase, 3? processing and DNA strand transfer, are required to integrate viral cDNA into a host cell chromosome. Integrase activity has been analyzed in vitro using purified protein and recombinant DNA substrates that model the U3 and U5 ends of viral cDNA or by using viral preintegration complexes (PICs) that form during virus infection. Numerous studies have investigated changes in integrase or viral DNA for effects on both 3? processing and DNA strand transfer activities using purified protein, but similar analyses have not been carried out using PICs. Here, we analyzed PICs from human immunodeficiency virus type 1 (HIV-1) strain 604del, an integration-defective mutant lacking 26 bp of U5, and revE1, a revertant of 604del containing an additional 19-bp deletion, for levels of 3? processing activity that occurred in infected cells and for levels of in vitro DNA strand transfer activity. Whereas revE1 supported one-third to one-half of the level of wild-type DNA strand transfer activity, the level of 604del DNA strand transfer activity was undetectable. Surprisingly, integrase similarly processed the 3? ends of 604del and revE1 in vivo. We therefore conclude that 604del is blocked in its ability to replicate in cells after the 3? processing step of retroviral integration. Whereas Western blotting showed that wild-type, revE1, and 604del PICs contained similar levels of integrase protein, Mu-mediated PCR footprinting revealed only minimal protein-DNA complex formation at the ends of 604del cDNA. We propose that 604del is replication defective because proteins important for DNA strand transfer activity do not stably associate with this cDNA after in vivo 3? processing by integrase.

Chen, Hongmin; Engelman, Alan

2000-01-01

394

Evidence that Bean Golden Mosaic Virus Invades Non-phloem Tissue in Double Infections with Tobacco Mosaic Virus  

Microsoft Academic Search

SUMMARY Bean leaves that had been doubly infected systemically with the legume strain of tobacco mosaic virus (CP-TMV) and bean golden mosaic virus (BGMV) were studied ultrastructurally. Virus particles and the cytopathological changes associated with each virus in single infections occurred within the same cell when plants were doubly infected, indicating that individual systemically infected host cells can multiply viruses

R. J. Carr; K. S. Kim

1983-01-01

395

Bunyaviridae: Morphologic and Morphogenetic Similarities of Bunyamwera Serologic Supergroup Viruses and Several Other Arthropod-Borne Viruses  

Microsoft Academic Search

Summary Thin section electron microscopic examination of several viruses of the Bunyamwera serologic supergroup of arbo viruses confirmed their precise similarities in morphology and morphogenesis and their differences from viruses of other groups. Several viruses that are serologically unrelated to the supergroup were indistinguishable from Bunyamwera virus when observed in the same way. A separate taxonomic group or ‘family’, ultimately

Frederick A. Murphy; Alyne K. Harrison; Sylvia G. Whitfield

1973-01-01

396

A Pathogenic Threshold of Virus Load Defined in Simian Immunodeficiency Virus or Simian-Human Immunodeficiency VirusInfected Macaques  

Microsoft Academic Search

To determine if a specific pathogenic threshold of plasma viral RNA could be defined irrespective of virus strain, RNA levels in the plasma of more than 50 infected rhesus macaques (Macaca mulatta) were measured. Animals were inoculated intravenously with either simian immunodeficiency virus (SIV) or simian-human immunodeficiency virus (SHIV) strains of known pathogenic potential (SIV8980, SIVsmm-3, SIVmac32H\\/J5, SIVmac32H\\/1XC, reverse transcriptase-SHIV,

PETER TEN HAAFT; BABS VERSTREPEN; KLAUS UBERLA; BRIGITTE ROSENWIRTH; JONATHAN HEENEY

1998-01-01

397

Virus-Specific Cofactor Requirement and Chimeric Hepatitis C Virus\\/GB Virus B Nonstructural Protein 3  

Microsoft Academic Search

GB virus B (GBV-B) is closely related to hepatitis C virus (HCV) and causes acute hepatitis in tamarins (Saguinus species), making it an attractive surrogate virus for in vivo testing of anti-HCV inhibitors in a small monkey model. It has been reported that the nonstructural protein 3 (NS3) serine protease of GBV-B shares similar substrate specificity with its counterpart in

NANCY BUTKIEWICZ; NANHUA YAO; WEIDONG ZHONG; JACQUELYN WRIGHT-MINOGUE; PAUL INGRAVALLO; RUMIN ZHANG; JAMES DURKIN; DAVID N. STANDRING; BAHIGE M. BAROUDY; DAVID V. SANGAR; STANLEY M. LEMON; JOHNSON Y. N. LAU; ZHI HONG

2000-01-01

398

Host range and some properties of Physalis mosaic virus, a new virus of the turnip yellow mosaic virus group  

Microsoft Academic Search

An apparently undescribed virus was isolated fromPhysalis subglabrata in Illinois, USA, and its properties were studied. The virus was namedPhysalis mosaic virus (PMV). It was readily transmitted by sap inoculation to 23 out of 34 Solanaceae tested, toChenopodium foetidum andSonchus oleraceus but not to 28 other non-solanaceous species inoculated. Purified preparations of PMV contained isometric particles of 27 nm in

D. Peters; A. F. L. M. Derks

1974-01-01

399

Human immunodeficiency virus, herpes virus infections, and pulmonary vascular disease  

PubMed Central

The following state-of-the-art seminar was delivered as part of the Aspen Lung Conference on Pulmonary Hypertension and Vascular Diseases held in Aspen, Colorado in June 2012. This paper will summarize the lecture and present results from a nonhuman primate model of infection with Simian (Human) Immunodeficiency Virus - nef chimeric virions as well as the idea that polymorphisms in the HIV-1 nef gene may be driving the immune response that results in exuberant inflammation and aberrant endothelial cell (EC) function. We will present data gathered from primary HIV nef isolates where we tested the biological consequences of these polymorphisms and how their presence in human populations may predict patients at risk for developing this disease. In this article, we also discuss how a dysregulated immune system, in conjunction with a viral infection, could contribute to pulmonary arterial hypertension (PAH). Both autoimmune diseases and some viruses are associated with defects in the immune system, primarily in the function of regulatory T cells. These T-cell defects may be a common pathway in the formation of plexiform lesions. Regardless of the route by which viruses may lead to PAH, it is important to recognize their role in this rare disease.

Flores, Sonia C.; Almodovar, Sharilyn

2013-01-01

400

Neoplastic transformation of chimpanzee cells induced by adenovirus type 12--simian virus 40 hybrid virus.  

PubMed Central

The adenovirus 12--simian virus 40 hybrid virus produced neoplastic transformation of chimpanzee skin fibroblasts in vitro. The transformed fibroblasts showed morphological alteration and became permanent lines. The transformed cells contained both adenovirus 12 and simian virus 40 large tumor antigens and were virus producers. However at passage 9, one line (WES) was found to be a nonproducer, producing neither infectious virus nor virus-specific antigen detectable by the complement fixation test. Virus particles were not detected nor could infectious hybrid virus be rescued from this line by cocultivation with Vero cells. The transformed cells formed large cell aggregates and grew in liquid growth medium above an agar base, formed colonies in soft agar, and grew to high saturation densities; the normal chimpanzee skin fibroblasts did not. One transformed WES line produced tumors when transplanted subcutaneously into newborn nude mice, thus providing an important tool for studying tumor immunity in the chimpanzee. Images

Rhim, J S; Trimmer, R; Arnstein, P; Huebner, R J

1981-01-01

401

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

PubMed Central

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.

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

402

Evolution and ecology of influenza A viruses.  

PubMed Central

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) There is evidence that most new human pandemic strains and variants have originated in southern China. (viii) There is speculation that pigs may serve as the intermediate host in genetic exchange between influenza viruses in avian and humans, but experimental evidence is lacking. (ix) Once the ecological properties of influenza viruses are understood, it may be possible to interdict the introduction of new influenza viruses into humans. Images

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

1992-01-01

403

Los dilemas del desarrollo territorial: repercusiones del zapatismo en la Selva Lacandona de Chiapas1  

Microsoft Academic Search

Este artículo discute los dilemas del desarrollo territorial en la Selva Lacandona. En particular analiza las relaciones entre movimientos sociales, nuevas formas de gobernanza ambiental y desarrollo en esta región del estado de Chiapas, en México. Con base en el llamado enfoque territorial del desarrollo rural (Schejtman y Berdegué, 2004), planteamos que en el contexto actual de globalización, para lograr

Luis Reygadas

404

Virus infections in the nervous system.  

PubMed

Virus infections usually begin in peripheral tissues and can invade the mammalian nervous system (NS), spreading into the peripheral (PNS) and more rarely the central (CNS) nervous systems. The CNS is protected from most virus infections by effective immune responses and multilayer barriers. However, some viruses enter the NS with high efficiency via the bloodstream or by directly infecting nerves that innervate peripheral tissues, resulting in debilitating direct and immune-mediated pathology. Most viruses in the NS are opportunistic or accidental pathogens, but a few, most notably the alpha herpesviruses and rabies virus, have evolved to enter the NS efficiently and exploit neuronal cell biology. Remarkably, the alpha herpesviruses can establish quiescent infections in the PNS, with rare but often fatal CNS pathology. Here we review how viruses gain access to and spread in the well-protected CNS, with particular emphasis on alpha herpesviruses, which establish and maintain persistent NS infections. PMID:23601101

Koyuncu, Orkide O; Hogue, Ian B; Enquist, Lynn W

2013-04-17

405

Satellite RNAs and Satellite Viruses of Plants  

PubMed Central

The view that satellite RNAs (satRNAs) and satellite viruses are purely molecular parasites of their cognate helper viruses has changed. The molecular mechanisms underlying the synergistic and/or antagonistic interactions among satRNAs/satellite viruses, helper viruses, and host plants are beginning to be comprehended. This review aims to summarize the recent achievements in basic and practical research, with special emphasis on the involvement of RNA silencing mechanisms in the pathogenicity, population dynamics, and, possibly, the origin(s) of these subviral agents. With further research following current trends, the comprehensive understanding of satRNAs and satellite viruses could lead to new insights into the trilateral interactions among host plants, viruses, and satellites.

Hu, Chung-Chi; Hsu, Yau-Heiu; Lin, Na-Sheng

2009-01-01

406

Fatal Case of Deer Tick Virus Encephalitis  

PubMed Central

SUMMARY Deer tick virus is related to Powassan virus, a tickborne encephalitis virus. A 62-year-old man presented with a meningoencephalitis syndrome and eventually died. Analyses of tissue samples obtained during surgery and at autopsy revealed a widespread necrotizing meningoencephalitis. Nucleic acid was extracted from formalin-fixed tissue, and the presence of deer tick virus was verified on a flavivirus-specific polymerase-chain-reaction (PCR) assay, followed by sequence confirmation. Immunohistochemical analysis with antisera specific for deer tick virus identified numerous immunoreactive neurons, with prominent involvement of large neurons in the brain stem, cerebellum, basal ganglia, thalamus, and spinal cord. This case demonstrates that deer tick virus can be a cause of fatal encephalitis.

Tavakoli, Norma P.; Wang, Heng; Dupuis, Michelle; Hull, Rene; Ebel, Gregory D.; Gilmore, Emily J.; Faust, Phyllis L.

2010-01-01

407

Genomic organization of Borna disease virus.  

PubMed Central

Borna disease virus is a neurotropic negative-strand RNA virus that infects a wide range of vertebrate hosts, causing disturbances in movement and behavior. We have cloned and sequenced the 8910-nucleotide viral genome by using RNA from Borna disease virus particles. The viral genome has complementary 3' and 5' termini and contains antisense information for five open reading frames. Homology to Filoviridae, Paramyxoviridae, and Rhabdoviridae is found in both cistronic and extracistronic regions. Northern analysis indicates that the virus transcribes mono- and polycistronic RNAs and uses termination/polyadenylylation signals reminiscent of those observed in other negative-strand RNA viruses. Borna disease virus is likely to represent a previously unrecognized genus, bornaviruses, or family, Bornaviridae, within the order Mononegavirales. Images

Briese, T; Schneemann, A; Lewis, A J; Park, Y S; Kim, S; Ludwig, H; Lipkin, W I

1994-01-01

408

Elution of viruses from coastal sediments.  

PubMed Central

Enteric viruses were eluted from estuarine sediments by using four organic mixtures; these solutions, with or without various supplements, were compared by determining their abilities to desorb virus from sediments taken from shellfish-harvesting sites. The least effective eluents consisted of glycine buffer, milk preparations, and beef extract paste. When virus type and sediment composition were taken into consideration, higher percentages of virus recovery were achieved with isoelectric casein, powdered beef extract, and nutrient broth mixtures. In addition to the type of eluent used, variations in virus recovery were due to the pH of the eluent, the composition of the sediment, and the type of virus being extracted. No clear distinction between the values of protein and inorganic ion supplements could be made.

Tsai, S C; Ellender, R D; Johnson, R A; Howell, F G

1983-01-01

409

Impacts of West Nile Virus on wildlife  

USGS Publications Warehouse

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.

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

2004-01-01

410

Virus-Based Chemical and Biological Sensing  

PubMed Central

Viruses have recently proven useful for the detection of target analytes such as explosives, proteins, bacteria, viruses, spores, and toxins with high selectivity and sensitivity. Bacteriophages (often shortened to phages), viruses that specifically infect bacteria, are currently the most studied viruses, mainly because target-specific nonlytic phages (and the peptides and proteins carried by them) can be identified by using the well-established phage display technique, and lytic phages can specifically break bacteria to release cell-specific marker molecules such as enzymes that can be assayed. In addition, phages have good chemical and thermal stability, and can be conjugated with nanomaterials and immobilized on a transducer surface in an analytical device. This Review focuses on progress made in the use of phages in chemical and biological sensors in combination with traditional analytical techniques. Recent progress in the use of virus—nanomaterial composites and other viruses in sensing applications is also high-lighted.

Mao, Chuanbin; Liu, Aihua; Cao, Binrui

2009-01-01

411

Whitefly transmission of sweet potato viruses.  

PubMed

Three genera of plant viruses, Begomovirus (Geminiviridae), Crinivirus (Closteroviridae) and Ipomovirus (Potyviridae), contain members that infect sweet potato (Ipomoea batatas) and are transmitted by whiteflies. The begomoviruses, Sweet potato leaf curl virus (SPLCV) and Ipomoea leaf curl virus (ILCV), and the ipomovirus Sweet potato mild mottle virus are transmitted by Bemisia tabaci, the sweet potato whitefly. The crinivirus, Sweet potato chlorotic stunt virus (SPCSV), is transmitted by B. tabaci and Trialeurodes abutilonea, the bandedwinged whitefly. Transmission experiments were done with three of these viruses using laboratory-reared whiteflies and 2-day acquisition and transmission feeding periods. SPLCV and ILCV were transmitted from single and double infections by B. tabaci at rates of 5-10%. Transmission rates for SPLCV by B. tabaci were 15-20%. T. abutilonea transmitted SPCSV at a rate of ca. 3% but did not transmit ILCV or SPLCV. PMID:15036843

Valverde, Rodrigo A; Sim, Jeonggu; Lotrakul, Pongtharin

2004-03-01

412

Human and Animal Viruses in Food (Including Taxonomy of Enteric Viruses)  

Microsoft Academic Search

1.0. INTRODUCTION In recent years, there has been an increase in the incidence of food-borne diseases worldwide, with viruses now recognized as a major cause of these illnesses. The viruses implicated in food-borne disease are the enteric viruses, which are found in the human gut, excreted in human feces, and transmitted by the fecal-oral route. Many different viruses are found

Gail E. Greening

413

Slow Evolutionary Rate of GB Virus C\\/Hepatitis G Virus  

Microsoft Academic Search

.   With the aim of elucidating evolutionary features of GB virus C\\/hepatitis G virus (GBV-C\\/HGV), molecular evolutionary analyses\\u000a were conducted using the entire coding region of this virus. In particular, the rate of nucleotide substitution for this virus\\u000a was estimated to be less than 9.0 × 10?6 per site per year, which was much slower than those for other RNA

Yoshiyuki Suzuki; Kazuhiko Katayama; Shuetsu Fukushi; Tsutomu Kageyama; Akira Oya; Hirofumi Okamura; Yasuhito Tanaka; Masashi Mizokami; Takashi Gojobori

1999-01-01

414

Virus Neutralising Antibodies Against 22 Bovine Viral Diarrhoea Virus Isolates in Vaccinated Calves  

Microsoft Academic Search

Seven of nine colostrum deprived calves, free from bovine viral diarrhoea virus (BVDV), were vaccinated with a commercially available vaccine containing two inactivated strains of BVDV, an inactivated strain of bovine herpesvirus-1 and modified-live strains of bovine respiratory syncytial virus and para-influenza-3 virus. The two other calves were kept as controls. The virus neutralising (VN) antibodies induced by vaccination were

C. Hamers; E. Di valentin; C. Lecomte; M. Lambot; E. Joris; B. Genicot; P. Pastoret

2002-01-01

415

Systemic vaccination with inactivated bovine virus diarrhoea virus protects against respiratory challenge  

Microsoft Academic Search

Inactivated bovine virus diarrhoea virus, strain 11249nc, inoculated subcutaneously three times with Quil-A into calves protected against intranasal challenge with the same strain. Virus was isolated from nasopharyngeal swabs taken 4 to 8 days post challenge and blood taken 4 to 6 days post challenge from control calves but not from vaccinated calves. A second strain of virus, Kyl203nc, was

C. J. Howard; M. C. Clarke; P. Sopp; J. Brownlie

1994-01-01

416

Host Range Restriction of Parainfluenza Virus Growth Occurs at the Level of Virus Genome Replication  

Microsoft Academic Search

To illuminate the molecular basis for host range restriction of parainfluenza virus replication, we have examined the types of virus macromolecules produced during abortive infection of nonpermissive MDBK cells with human parainfluenza virus type 1 (hPIV1). While these cells do not support production of hPIV1 virus, they can be infected by hPIV1 as evidenced by accumulation of intracellular viral NP

TAO TAO; KEVIN W. RYAN

1996-01-01

417

Recombinant measles viruses expressing heterologous antigens of mumps and simian immunodeficiency viruses  

Microsoft Academic Search

We have genetically engineered a panel of recombinant measles viruses (rMVs) that express from various positions within the MV genome either the HN or F surface glycoproteins of mumps virus (MuV) or the env, gag or pol proteins from simian immunodeficiency virus (SIV). All rMVs were rescued from the respective antigenomic plasmid constructs; progeny viruses replicated comparably to the progenitor

Z. Wang; L. Hangartner; T. I. Cornu; L. R. Martin; A. Zuniga; M. A. Billeter; H. Y. Naim

2001-01-01

418

Virus-host interaction in the simian immunodeficiency virus-infected brain  

Microsoft Academic Search

With the increased survival of human immunodeficiency virus (HIV)-infected individuals resulting from therapy, disorders in\\u000a other target organs of the virus, such as the brain, are becoming more prevalent. Here the author reviews his laboratory’s\\u000a work on the simian immunodeficiency virus (SIV)\\/nonhuman model of acquired immunodeficiency syndrome (AIDS), which has revealed\\u000a unique characteristics of both the virus that infects the

Howard S. Fox

2008-01-01

419

Tentative description of Hippeastrum latent virus in Hippeastrum hybridum plants and differentiation from Hippeastrum mosaic virus  

Microsoft Academic Search

In mosaic-diseased plants ofHippeastrum hybridum two viruses were found. One virus with a normal length of 706 nm caused local lesions onHyoscyamus niger test plants and mosaic symptoms in the leaves ofH. hybridum. This virus was identified with theHippeastrum mosaic virus (HMV) (*\\/*?*\\/*?E\\/E?S\\/*) and had a dilution end point between 10?3 and 10?4, a thermal inactivation point between 55–60°C and

J. E. Brölman-Hupkes; Commelin Scholten

1975-01-01

420

21 CFR 866.3305 - Herpes simplex virus serological assays.  

Code of Federal Regulations, 2010 CFR

...2009-04-01 2009-04-01 false Herpes simplex virus serological assays. 866... Serological Reagents § 866.3305 Herpes simplex virus serological assays. (a) Identification . Herpes simplex virus serological assays...

2009-04-01

421

21 CFR 866.3305 - Herpes simplex virus serological assays.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Herpes simplex virus serological assays. 866... Serological Reagents § 866.3305 Herpes simplex virus serological assays. (a) Identification . Herpes simplex virus serological assays...

2010-04-01

422

21 CFR 866.3330 - Influenza virus serological reagents.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Influenza virus serological reagents. 866...Serological Reagents § 866.3330 Influenza virus serological reagents. (a) Identification. Influenza virus serological reagents are...

2010-04-01

423

9 CFR 113.203 - Feline Panleukopenia Vaccine, Killed Virus.  

Code of Federal Regulations, 2013 CFR

... Feline Panleukopenia Vaccine, Killed Virus. 113.203 Section 113.203 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.203 Feline...

2013-01-01

424

9 CFR 113.216 - Bovine Rhinotracheitis Vaccine, Killed Virus.  

Code of Federal Regulations, 2013 CFR

...Bovine Rhinotracheitis Vaccine, Killed Virus. 113.216 Section 113.216 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.216 Bovine...

2013-01-01

425

9 CFR 113.210 - Feline Calicivirus Vaccine, Killed Virus.  

Code of Federal Regulations, 2013 CFR

... Feline Calicivirus Vaccine, Killed Virus. 113.210 Section 113.210 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.210 Feline...

2013-01-01

426

9 CFR 113.214 - Parvovirus Vaccine, Killed Virus (Canine).  

Code of Federal Regulations, 2013 CFR

... false Parvovirus Vaccine, Killed Virus (Canine). 113.214 Section 113...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.214 Parvovirus...

2013-01-01

427

9 CFR 113.34 - Detection of hemagglutinating viruses.  

Code of Federal Regulations, 2013 CFR

... false Detection of hemagglutinating viruses. 113.34 Section 113.34 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...113.34 Detection of hemagglutinating viruses. The test for detection of...

2013-01-01

428

9 CFR 113.205 - Newcastle Disease Vaccine, Killed Virus.  

Code of Federal Regulations, 2013 CFR

...false Newcastle Disease Vaccine, Killed Virus. 113.205 Section 113.205 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.205 Newcastle...

2013-01-01

429

21 CFR 866.3520 - Rubeola (measles) virus serological reagents.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Rubeola (measles) virus serological reagents. 866.3520... § 866.3520 Rubeola (measles) virus serological reagents. (a) Identification. Rubeola (measles) virus serological reagents are devices...

2013-04-01

430

9 CFR 113.213 - Pseudorabies Vaccine, Killed Virus.  

Code of Federal Regulations, 2013 CFR

... false Pseudorabies Vaccine, Killed Virus. 113.213 Section 113.213 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.213...

2013-01-01

431

9 CFR 113.204 - Mink Enteritis Vaccine, Killed Virus.  

Code of Federal Regulations, 2013 CFR

...false Mink Enteritis Vaccine, Killed Virus. 113.204 Section 113.204 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.204 Mink...

2013-01-01

432

21 CFR 866.3480 - Respiratory syncytial virus serological reagents.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Respiratory syncytial virus serological reagents. 866.3480... § 866.3480 Respiratory syncytial virus serological reagents. (a) Identification. Respiratory syncytial virus serological reagents are devices...

2013-04-01

433

21 CFR 866.3510 - Rubella virus serological reagents.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Rubella virus serological reagents. 866.3510 Section...Serological Reagents § 866.3510 Rubella virus serological reagents. (a) Identification. Rubella virus serological reagents are devices...

2013-04-01

434

21 CFR 866.3400 - Parainfluenza virus serological reagents.  

Code of Federal Regulations, 2013 CFR

... 2013-04-01 false Parainfluenza virus serological reagents. 866.3400 Section...Reagents § 866.3400 Parainfluenza virus serological reagents. (a) Identification. Parainfluenza virus serological reagents are devices...

2013-04-01

435

9 CFR 113.211 - Feline Rhinotracheitis Vaccine, Killed Virus.  

Code of Federal Regulations, 2013 CFR

...Feline Rhinotracheitis Vaccine, Killed Virus. 113.211 Section 113.211 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.211 Feline...

2013-01-01

436

9 CFR 113.201 - Canine Distemper Vaccine, Killed Virus.  

Code of Federal Regulations, 2013 CFR

...false Canine Distemper Vaccine, Killed Virus. 113.201 Section 113.201 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.201 Canine...

2013-01-01

437

9 CFR 113.201 - Canine Distemper Vaccine, Killed Virus.  

Code of Federal Regulations, 2010 CFR

...false Canine Distemper Vaccine, Killed Virus. 113.201 Section 113.201 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.201 Canine...

2009-01-01

438

Stability at systems of usual differential equations in virus dynamics  

NASA Astrophysics Data System (ADS)

In this paper we discuss different models of differential equations systems, that describe virus dynamics in different situations (HIV-virus and Hepatitis B-virus). We inquire the stability of differential equations. We use theorems of the stability theory.

Schröer, H.

439

21 CFR 866.3510 - Rubella virus serological reagents.  

Code of Federal Regulations, 2010 CFR

...Identification. Rubella virus serological reagents are...identify antibodies to rubella virus in serum. The identification...in the uterus with rubella virus may be born with multiple congenital...rubella syndrome). (b) Classification. Class II. The...

2009-04-01

440

21 CFR 866.3510 - Rubella virus serological reagents.  

Code of Federal Regulations, 2010 CFR

...Identification. Rubella virus serological reagents are...identify antibodies to rubella virus in serum. The identification...in the uterus with rubella virus may be born with multiple congenital...rubella syndrome). (b) Classification. Class II. The...

2010-04-01

441

21 CFR 866.3480 - Respiratory syncytial virus serological reagents.  

Code of Federal Regulations, 2010 CFR

...diagnosis of respiratory syncytial virus infections and provides epidemiological...on diseases caused by these viruses. Respiratory syncytial viruses cause a number of respiratory...bronchopneumonia. (b) Classification. Class I (general...

2009-04-01

442

21 CFR 866.3940 - West Nile virus serological reagents.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false West Nile virus serological reagents. 866...Serological Reagents § 866.3940 West Nile virus serological reagents. (a) Identification. West Nile virus serological reagents...

2013-04-01

443

21 CFR 866.3940 - West Nile virus serological reagents.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false West Nile virus serological reagents. 866...Serological Reagents § 866.3940 West Nile virus serological reagents. (a) Identification. West Nile virus serological reagents...

2010-04-01

444

21 CFR 866.3940 - West Nile virus serological reagents.  

Code of Federal Regulations, 2010 CFR

...2009-04-01 2009-04-01 false West Nile virus serological reagents. 866...Serological Reagents § 866.3940 West Nile virus serological reagents. (a) Identification. West Nile virus serological reagents...

2009-04-01

445

21 CFR 866.3520 - Rubeola (measles) virus serological reagents.  

Code of Federal Regulations, 2010 CFR

...2009-04-01 2009-04-01 false Rubeola (measles) virus serological reagents...Serological Reagents § 866.3520 Rubeola (measles) virus serological reagents. (a) Identification. Rubeola (measles) virus serological...

2009-04-01

446

21 CFR 866.3520 - Rubeola (measles) virus serological reagents.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Rubeola (measles) virus serological reagents...Serological Reagents § 866.3520 Rubeola (measles) virus serological reagents. (a) Identification. Rubeola (measles) virus serological...

2010-04-01

447

Foot-and-mouth disease virus L peptidase  

Technology Transfer Automated Retrieval System (TEKTRAN)

Foot-and-mouth disease virus (FMDV), equine rhinitis A virus (ERAV) and bovine rhinitis B virus (BRBV) comprise the genus Aphthovirus of the Picornaviridae family. Seven genera within this family, Aphthoviruses, Cardioviruses, Erboviruses (ERBV), Kobuviruses, Senecaviruses, Sapeloviruses, and Tescho...

448

Influenza virus and neurological diseases.  

PubMed

Influenza viruses rarely cause acute encephalopathy. Post-influenzal encephalitis, which occurs a few weeks after recovery from influenza is thought to be an autoimmune process associated with demyelination and vasculopathy. It has been suggested that Economo lethargic encephalitis followed by postencephalitic Parkinsonism was associated with the influenza A epidemic of 1918 (Spanish flu). The incidence of Reye's syndrome has markedly decreased due to the avoidance of salicylates in the treatment of influenza or varicella. One inactivated flu vaccine is thought to have caused Guillain Barre syndrome due to molecular mimicry between viral protein and myelin, which triggered autoimmune responses. The persistence of influenza virus genes in neural cells as one of the causes of chronic degenerative diseases of the central nervous system by inducing apoptosis of the host cells is yet to be proven. PMID:9316161

Hayase, Y; Tobita, K

1997-08-01

449

West Nile Virus in California  

PubMed Central

West Nile virus (WNV) was first isolated in California during July 2003 from a pool of Culex tarsalis collected near El Centro, Imperial County. WNV transmission then increased and spread in Imperial and Coachella Valleys, where it was tracked by isolation from pools of Cx. tarsalis, seroconversions in sentinel chickens, and seroprevalence in free-ranging birds. WNV then dispersed to the city of Riverside, Riverside County, and to the Whittier Dam area of Los Angeles County, where it was detected in dead birds and pools of Cx. pipiens quinquefasciatus. By October, WNV was detected in dead birds collected from riparian corridors in Los Angeles, west to Long Beach, and through inland valleys south from Riverside to San Diego County. WNV was reported concurrently from Arizona in mid-August and from Baja, Mexico, in mid-November. Possible mechanisms for virus introduction, amplification, and dispersal are discussed.

Lothrop, Hugh; Chiles, Robert; Madon, Minoo; Cossen, Cynthia; Woods, Leslie; Husted, Stan; Kramer, Vicki; Edman, John

2004-01-01

450

Physical Chemistry of DNA Viruses  

NASA Astrophysics Data System (ADS)

The relative simplicity of viruses makes it possible to apply generic physical approaches to the understanding of their structure and function. We focus here on viruses that have double-stranded (ds)DNA genomes that are enclosed in a protein container called the capsid. Their structures are now known in precise detail from cryo-electron microscopy. dsDNA is a stiff, highly charged polymer, and typical viral DNAs have contour lengths 1000 times longer than the radius of the capsid into which they are introduced in the assembly process, which is driven by a biological motor. As a result, the confined DNA is highly stressed. The energy stored in the dsDNA, which is compressed to crystalline densities, drives the ejection of the genome into the host at the start of an infection. Experiments have examined the packaging and ejection of the genomes, which have also been the subject of analytic theories and simulations.

Knobler, Charles M.; Gelbart, William M.

2009-05-01

451

West Nile Virus Maps - 2002  

NSDL National Science Digital Library

The US Geological Survey Center for Integration of Natural Disaster Information has provided these maps of reported occurrences of West Nile Virus (WNV). "The West Nile Virus Surveillance System is intended to monitor the geographic and temporal spread of WNV over the contiguous United States." Maps include 2002 surveillance data for birds, humans, mosquitoes, sentinel chicken flocks, and data submitted by veterinarians. Maps from previous years are available, including comprehensive maps through 2000, and maps of 2001 data. It is unclear whether the 2002 maps are based on 2002 data alone, or include all data through June of 2002. Brief background on WNV and surveillance activities help make this site appealing to a broader audience.

452

Dengue Virus Infection in Africa  

PubMed Central

Reported incidence of dengue has increased worldwide in recent decades, but little is known about its incidence in Africa. During 1960–2010, a total of 22 countries in Africa reported sporadic cases or outbreaks of dengue; 12 other countries in Africa reported dengue only in travelers. The presence of disease and high prevalence of antibody to dengue virus in limited serologic surveys suggest endemic dengue virus infection in all or many parts of Africa. Dengue is likely underrecognized and underreported in Africa because of low awareness by health care providers, other prevalent febrile illnesses, and lack of diagnostic testing and systematic surveillance. Other hypotheses to explain low reported numbers of cases include cross-protection from other endemic flavivirus infections, genetic host factors protecting against infection or disease, and low vector competence and transmission efficiency. Population-based studies of febrile illness are needed to determine the epidemiology and true incidence of dengue in Africa.

Kuritsky, Joel N.; Letson, G. William; Margolis, Harold S.

2011-01-01

453

Dengue virus infection in Africa.  

PubMed

Reported incidence of dengue has increased worldwide in recent decades, but little is known about its incidence in Africa. During 1960-2010, a total of 22 countries in Africa reported sporadic cases or outbreaks of dengue; 12 other countries in Africa reported dengue only in travelers. The presence of disease and high prevalence of antibody to dengue virus in limited serologic surveys suggest endemic dengue virus infection in all or many parts of Africa. Dengue is likely underrecognized and underreported in Africa because of low awareness by health care providers, other prevalent febrile illnesses, and lack of diagnostic testing and systematic surveillance. Other hypotheses to explain low reported numbers of cases include cross-protection from other endemic flavivirus infections, genetic host factors protecting against infection or disease, and low vector competence and transmission efficiency. Population-based studies of febrile illness are needed to determine the epidemiology and true incidence of dengue in Africa. PMID:21801609

Amarasinghe, Ananda; Kuritsk, Joel N; Letson, G William; Margolis, Harold S

2011-08-01

454

West nile virus neuroinvasive disease.  

PubMed

West Nile virus (WNV), first recognized in North America in 1999, was responsible for the largest arboviral epidemic of human encephalitis in history and continues to be the most frequent cause of epidemic meningoencephalitis in North America. WNV neuroinvasive disease (WNND) occurs in fewer than 1% of infected individuals, with presentations including aseptic meningitis, encephalitis, and poliomyelitis. Between 1999 and 2009, over 12,000 cases of WNND were reported in the United States, with the peak annual incidence occurring in epidemics of 2002 and 2003. In this review, we first summarize the epidemiology of WNV over the past decade and the salient clinical features of WNND, including a discussion of laboratory and radiographic findings, risk factors, morbidity, and mortality. In addition, we review recent progress in our understanding of virus and host determinants of the pathogenesis of WNND, as well as the prospects for the development of specific therapeutic targets. PMID:21544522

Debiasi, Roberta L

2011-08-01

455

Do human polyoma viruses and human immunodeficiency virus share common co-receptors?  

PubMed

Host and/or viral factors involved in human polyomavirus (HPoV) infection in persons living with HIV remain unknown. A hypothesis is outlined suggesting the importance of the co-receptors CCR5, CCR2, and CXCR4 not only for HIV, but also for HPoV. Functionally capable receptors coded by wild-type (wt) genotypes could facilitate internalization of HPoV in the cell resulting in brain and/or kidney infection/s in HIV infected individuals. Forty-nine Bulgarians with HIV, all treated by HAART, without neurological and/or kidney disorders, were tested for JCV and BKV and genotyped for CCR5 (CCR5del32), CCR2 (CCR2-64I), and CXCR4 (SDF1-3'A). In 27/49 (55.1%) individuals a co-infection with HPoV was identified-BKV in 12/49 (24.5%), JCV-in another 12/49 (24.5%), and both viruses-in 3/49 (6.1%). A high frequency of wt CCR5 was found in patients with HPoV (91.7% for BKV and JCV and in 100% with both viruses). V/V of CCR2 was presented in 75% for BKV and JCV and in 66.7% for BKV plus JCV. SDF1-3'G/G predominated in JCV infected patients (75%), while G/A and A/A genotypes were more frequent in patients with BKV (41.7%). Also, 21/22 (95.4%) persons without HPoV infection were heterozygous for SDF1 and CCR2. The number of individuals bearing wt of all co-receptors in the group of persons not infected with HPoV was lower (P = 0.03) than that with polymorphism/s in one or two genes (SDF1 and CCR2) in the same group. The results suggest a probable role of co-receptors used by HIV to facilitate infection with HPoV. PMID:19950235

Borissov, Kalin; Tsekov, Iliya; Gavazova, Rayna; Kalvatchev, Zlatko; Argirova, Radka

2010-01-01

456

Transgenic gene silencing strategies for virus control  

Microsoft Academic Search

Co-suppression of transgenes and their homologous viral sequences by RNA silencing is a powerful strategy for achieving high-level\\u000a virus resistance in plants. This review provides a brief overview of RNA silencing mechanisms in plants and discusses important\\u000a transgene construct design features underpinning successful RNA silencing-mediated transgenic virus control. Application of\\u000a those strategies to protect horticultural and field crops from virus

R. G. Dietzgen; N. Mitter

2006-01-01

457

Replication of avian influenza viruses in humans  

Microsoft Academic Search

Summary Volunteers inoculated with avian influenza viruses belonging to subtypes currently circulating in humans (H1N1 and H3N2) were largely refractory to infection. However 11 out of 40 volunteers inoculated with the avian subtypes, H4N8, H6N1, and H10N7, shed virus and had mild clinical symptoms: they did not produce a detectable antibody response. This was presumably because virus multiplication was limited

A. S. Beare; R. G. Webster

1991-01-01

458

Viruses and Cancer--A Review  

PubMed Central

The answer to the important question, “Do viruses play a role in human cancer?” is still unknown. Although many scientists think that they may play a role, straightforward attempts to isolate human tumor viruses in animals or in tissue cultures have failed. Possibly the most sensitive test object, newborn human infants, of course cannot be used as test objects, and this may explain the failure to isolate human tumor viruses. At present, it would appear that the best means of tackling the problem of viral-induced carcinogenesis is to study the basic characteristics of known tumor viruses and the basic aspects of their interactions with cells. Both RNA-containing and DNA-containing viruses, two obviously different classes of virus, can cause cancer and therefore both classes must be studied in order to obtain a complete picture of the role of viruses in causing cancer in animals and cell transformation in vitro. Such basic studies already have yielded information of great importance to general biology. A number of exciting developments have occurred in the area of virus-induced cancer. One of these is the oncogenic capacity in hamsters of certain human adenoviruses, and an intensive probe of their possible role in human cancer is in progress. Another is the detection by electron microscopy of virus-like particles in the tissues and serum of patients with leukemia. Rigid criteria have been suggested to establish etiologic significance of viruses recovered from human cancer tissues and of the virus-like particles observed by electron microscopy in serum or malignant tissues from cancer patients. If viruses are eventually found to play a role in human cancer, then perhaps the disease can be prevented by vaccines and treated with antiviral substances. ImagesFigure 1.Figure 2.Figure 3.Figure 4.Figure 5.Figure 6.Figure 7.

McAllister, Robert M.

1965-01-01

459

Nucleotide sequence of cassava latent virus DNA  

Microsoft Academic Search

Only two groups of plant viruses, the caulimoviruses1,2 and the geminiviruses3, are known to contain a genome of DNA. Unlike that of the caulimoviruses, the genome of the geminivinises is composed of single-stranded, covalently-closed circles of DNA. There is evidence that the geminiviruses, specifically bean golden mosaic virus4 and tomato golden mosaic virus5, have a genome composed of two similar-sized

John Stanley; Michael R. Gay

1983-01-01

460

Cell-Free Synthesis of Encephalomyocarditis Virus  

PubMed Central

We developed a system for complete replication of encephalomyocarditis virus (EMCV) in a test tube by using an in vitro translation extract from Krebs-2 cells. Efficient virus synthesis occurred in a narrow range of Mg2+ and EMCV RNA concentrations. Excess input RNA impaired RNA replication and virus production but not translation. This suggests the existence of a negative-feedback mechanism for regulation of RNA replication by the viral plus-strand RNA or proteins.

Svitkin, Yuri V.; Sonenberg, Nahum

2003-01-01

461

Tubule-Guided Movement of Plant Viruses  

Microsoft Academic Search

Plant viruses move from cell to cell through plasmodesmata, which are complex gatable pores in the\\u000a cell wall. While plasmodesmata normally allow the diffusion of only small molecules, they can be biochemically\\u000a or structurally modified by virus-encoded movement proteins to enable the passage of either infectious ribonucleoprotein\\u000a complexes or entire virus particles. In the latter case, the movement protein forms

Christophe Ritzenthaler; Christina Hofmann

462

Dating the emergence of pandemic influenza viruses.  

PubMed

Pandemic influenza viruses cause significant mortality in humans. In the 20th century, 3 influenza viruses caused major pandemics: the 1918 H1N1 virus, the 1957 H2N2 virus, and the 1968 H3N2 virus. These pandemics were initiated by the introduction and successful adaptation of a novel hemagglutinin subtype to humans from an animal source, resulting in antigenic shift. Despite global concern regarding a new pandemic influenza, the emergence pathway of pandemic strains remains unknown. Here we estimated the evolutionary history and inferred date of introduction to humans of each of the genes for all 20th century pandemic influenza strains. Our results indicate that genetic components of the 1918 H1N1 pandemic virus circulated in mammalian hosts, i.e., swine and humans, as early as 1911 and was not likely to be a recently introduced avian virus. Phylogenetic relationships suggest that the A/Brevig Mission/1/1918 virus (BM/1918) was generated by reassortment between mammalian viruses and a previously circulating human strain, either in swine or, possibly, in humans. Furthermore, seasonal and classic swine H1N1 viruses were not derived directly from BM/1918, but their precursors co-circulated during the pandemic. Mean estimates of the time of most recent common ancestor also suggest that the H2N2 and H3N2 pandemic strains may have been generated through reassortment events in unknown mammalian hosts and involved multiple avian viruses preceding pandemic recognition. The possible generation of pandemic strains through a series of reassortment events in mammals over a period of years before pandemic recognition suggests that appropriate surveillance strategies for detection of precursor viruses may abort future pandemics. PMID:19597152

Smith, Gavin J D; Bahl, Justin; Vijaykrishna, Dhanasekaran; Zhang, Jinxia; Poon, Leo L M; Chen, Honglin; Webster, Robert G; Peiris, J S Malik; Guan, Yi

2009-07-13

463

Antigenic comparison of swine influenza virus isolates  

Microsoft Academic Search

Summary Cross hemagglutination inhibition (HI) and neuraminidase inhibition (NI) tests demonstrated strong antigenic relationship between A\\/Swine\\/Wisconsin\\/1\\/73 (SW\\/73) and A\\/Swine\\/Shope\\/15\\/31 (SW\\/31) influenza viruses. An eightyone fold purification of virus was achieved by adsorption and elution followed by differential ultracentrifugation and sedimentation through linear sucrose gradient. Radio-immunoassay using purified125I labeled viral antigens revealed antigenic variation between the two virus isolates. Neuraminidase of

D. M. Nath; L. S. Rodkey; H. C. Minocha

1975-01-01

464

Virus Cross-infection in Paediatric Wards  

Microsoft Academic Search

In a survey of virus cross-infection in paediatric wards there were 15 cross-infections due to respiratory syncytial (R.S.) virus and 16 due to influenza A, both during a four-month period, and 19 due to parainfluenza viruses over two years. The illnesses produced by these infections acquired in hospital ranged from a slight cold to severe pneumonia: in 17 of the

P. S. Gardner; S. D. M. Court; J. T. Brocklebank; M. A. P. S. Downham; D. Weightman

1973-01-01

465

Bacterial virus contamination of fetal bovine sera  

Microsoft Academic Search

Summary  Thirty-seven lots of fetal bovine sera were examined for the presence ofEscherichia coli-specific bacterial viruses, and 23 were positive. No correlation was found between the presence of bacterial virus and poor\\u000a growth-promoting qualities of the sera. One bacterial virus contaminant of fetal bovine serum was isolated and examined by\\u000a electron microscopy.

Fred C. Chu; Joyce B. Johnson; Henry C. Orr; Peter G. Probst; John C. Petricciani

1973-01-01

466

Structure of Turnip Yellow Mosaic Virus  

Microsoft Academic Search

IN this communication we report some of the results of the early stages of an X-ray diffraction study of crystals of turnip yellow mosaic virus1,2. The two most important conclusions from the interpretation of the X-ray diagrams concern: (a) the packing of the virus particles in the crystal; and (b) the arrangement of protein sub-units in the individual virus particle.

A. Klug; J. T. Finch; Rosalind E. Franklin

1957-01-01

467

Varicella Zoster Virus Immune Evasion Strategies  

Microsoft Academic Search

\\u000a The capacity of varicella zoster virus (VZV) to cause varicella (chickenpox) relies upon multiple steps, beginning with inoculation\\u000a of the host at mucosal sites with infectious virus in respiratory droplets. Despite the presence of a powerful immune defense\\u000a system, this virus is able to disseminate from the site of initial infection to multiple sites, resulting in the emergence\\u000a of distinctive

Allison Abendroth; Paul R. Kinchington; Barry Slobedman

468

Frequent reassortment among influenza C viruses.  

PubMed

In a 9-year survey from December 1990 to December 1999 in Sendai City, Japan, we succeeded in isolating a total of 45 strains of influenza C virus. These 45 strains were isolated in clusters within 4 months in a year, especially from winter to early summer. Previous studies of the hemagglutinin-esterase genes of various influenza C virus isolates revealed the existence of five distinct virus lineages (Aichi/1/81-, Yamagata/26/81-, Mississippi/80-, Sao Paulo/82-, and Kanagawa/1/76-related lineage) in Japan between 1970 and the early 1990s (Y. Matsuzaki, K. Mizuta, H. Kimura, K. Sugawara, E. Tsuchiya, H. Suzuki, S. Hongo, and K. Nakamura, J. Gen. Virol. 81:1447-1452, 2000). Antigenic and genetic analyses of the 45 strains showed that they could be divided into these five virus lineages and a few antigenic groups were cocirculating in Sendai City. In 1990 and 1991 the dominant antigenic group was the Aichi/1/81 virus group, and in 1992 it was Yamagata/26/81 virus group. The Mississippi/80 virus group was isolated from 1993 to 1996, and the Yamagata/26/81 virus group reemerged in 1996 and continued to circulate until 1999. This finding led us to a speculation that the replacement of the dominant antigenic groups had occurred by immune selection within the human population in the restricted area. Phylogenetic analysis of seven RNA segments showed that 44 viruses among the 45 strains isolated in our surveillance work were reassortant viruses that have various genome compositions distinguishable from those of the reference strains of the each lineage. This observation suggests that the reassortment between two different influenza C virus strains occurs frequently in nature and the genome composition of influenza C viruses may influence their ability to spread in humans. PMID:12502803

Matsuzaki, Y; Mizuta, K; Sugawara, K; Tsuchiya, E; Muraki, Y; Hongo, S; Suzuki, H; Nishimura, H

2003-01-01

469

Effects of Caffeine on Herpes Simplex Virus  

Microsoft Academic Search

Summary At concentrations greater than 1 mg\\/ml, caffeine inhibited plaque formation by herpes simplex virus type 1 (HSV-1), suppressed growth of HSV-1 at various steps of the replicative cycle, but did not inactivate virus infectivity. These effects were independent of each other and persisted through completion of virus replication, as determined by one-step growth studies. Some replication steps appeared to

Kimiyasu Shiraki; Fred Rapp

1988-01-01

470

Molecular cloning of lymphadenopathy-associated virus  

Microsoft Academic Search

Lymphadenopathy-associated virus (LAV) is a human retrovirus first isolated1 from a homosexual patient with lymphadenopathy syndrome, frequently a prodrome or a benign form of acquired immune deficiency syndrome (AIDS)2. Other LAV isolates have subsequently been recovered from patients with AIDS or pre-AIDS3-5 and all available data are consistent with the virus being the causative agent of AIDS. The virus is

Marc Alizon; Pierre Sonigo; Françoise Barré-Sinoussi; Jean-Claude Chermann; Pierre Tiollais; Luc Montagnier; Simon Wain-Hobson

1984-01-01

471

Epidemiology of virus infection and human cancer.  

PubMed

The International Agency for Research on Cancer (IARC) has comprehensively assessed the human carcinogenicity of biological agents. Seven viruses including Epstein-Barr virus (EBV), hepatitis B virus (HBV), hepatitis C virus (HCV), Kaposi's sarcoma herpes virus (KSHV), human immunodeficiency virus, type-1 (HIV-1), human T cell lymphotrophic virus, type-1 (HTLV-1), and human papillomavirus (HPV) have been classified as Group 1 human carcinogens by IARC. The conclusions are based on the findings of epidemiological and mechanistic studies. EBV, HPV, HTLV-1, and KSHV are direct carcinogens; HBV and HCV are indirect carcinogens through chronic inflammation; HIV-1 is an indirect carcinogen through immune suppression. Some viruses may cause more than one cancer, while some cancers may be caused by more than one virus. However, only a proportion of persons infected by these oncogenic viruses will develop specific cancers. A series of studies have been carried out to assess the viral, host, and environmental cofactors of EBV-associated nasopharyngeal carcinoma, HBV/HCV-associated hepatocellular carcinoma, and HPV-associated cervical carcinoma. Persistent infection and high viral load are important risk predictors of these virus-caused cancers. Risk calculators incorporating host and viral factors have also been developed for the prediction of long-term risk of hepatocellular carcinoma. These risk calculators are useful for the triage and clinical management of infected patients. Both clinical trials and national programs of immunization or antiviral therapy have demonstrated a significant reduction in the incidence of cancers caused by HBV, HCV, and HPV. Future researches on gene-gene and gene-environment interaction of oncogenic viruses and human host are in urgent need. PMID:24008291

Chen, Chien-Jen; Hsu, Wan-Lun; Yang, Hwai-I; Lee, Mei-Hsuan; Chen, Hui-Chi; Chien, Yin-Chu; You, San-Lin

2014-01-01

472

Allergens, Viruses, and Asthma Exacerbations  

Microsoft Academic Search

In adults and children with asthma, viral infections (rhinovirus (RV) infection being the most prevalent) will often trigger an increase in symptomatology. The mechanisms responsible for viral-induced exacerbations remain uncertain. Proposed mechanisms include direct infection of the lower respiratory tract, the inflammatory response to viruses, increases in bronchial responsiveness and up-regulation of intercellular adhesion molecule-1 expression in bronchial epithe- lium.

Clare S. Murray; Angela Simpson; Adnan Custovic

2004-01-01

473

Control of feline leukaemia virus  

Microsoft Academic Search

Feline leukaemia virus (FeLV) usually occurs in its natural species, the domestic cat. FeLV is also important to human individuals as a comparative model, as it may cause a variety of diseases, some malignant and some benign, such as immunosuppression, which bears a resemblance to AIDS (acquired immune deficiency syndrome) in man. FeLV is transmitted among cats by contagion. The

K. Weijer; F. G. C. M. Uytdehaag; A. D. M. E. Osterhaus

1989-01-01

474

Olfactory transmission of neurotropic viruses  

Microsoft Academic Search

Olfactory receptor neurons are unique in their anatomical structure and function. Each neuron is directly exposed to the external\\u000a environment at the site of its dendritic nerve terminals where it is exposed to macromolecules. These molecules can be incorporated\\u000a into by olfactory receptor neurons and transported transsynaptically to the central nervous system. Certain neurotropic pathogens\\u000a such as herpes simplex virus

Isamu Mori; Yukihiro Nishiyama; Takashi Yokochi; Yoshinobu Kimura

2005-01-01

475

Flow cytometric detection of viruses  

Microsoft Academic Search

Representatives from several different virus families (Baculoviridae, Herpesviridae, Myoviridae, Phycodnaviridae, Picornaviridae, Podoviridae, Retroviridae, and Siphoviridae) were stained using a variety of highly fluorescent nucleic acid specific dyes (SYBR Green I, SYBR Green II, OliGreen, PicoGreen) and examined using a standard flow cytometer equipped with a standard 15 mW argon-ion laser. The highest green fluorescence intensities were obtained using SYBR Green

Corina P. D. Brussaard; Dominique Marie; Gunnar Bratbak

2000-01-01

476

West Nile Virus Neuroinvasive Disease  

Microsoft Academic Search

West Nile virus (WNV), first recognized in North America in 1999, was responsible for the largest arboviral epidemic of human\\u000a encephalitis in history and continues to be the most frequent cause of epidemic meningoencephalitis in North America. WNV\\u000a neuroinvasive disease (WNND) occurs in fewer than 1% of infected individuals, with presentations including aseptic meningitis,\\u000a encephalitis, and poliomyelitis. Between 1999 and

Roberta L. DeBiasi

2011-01-01

477

Viruses and microRNAs  

Microsoft Academic Search

The discovery of RNA interference and cellular microRNAs (miRNAs) has not only affected how biological research is conducted but also revealed an entirely new level of post-transcriptional gene regulation. Here, I discuss the potential functions of the virally encoded miRNAs recently identified in several pathogenic human viruses and propose that cellular miRNAs may have had a substantial effect on viral

Bryan R Cullen

2006-01-01

478

Membrane Fusion Tropism and Heterotypic Functional Activities of the Nipah Virus and Hendra Virus Envelope Glycoproteins  

Microsoft Academic Search

Nipah virus (NiV) and Hendra virus (HeV) are novel paramyxoviruses from pigs and horses, respectively, that are responsible for fatal zoonotic infections of humans. The unique genetic and biological characteristics of these emerging agents has led to their classification as the prototypic members of a new genus within the Paramyxovirinae subfamily called Henipavirus. These viruses are most closely related to

Katharine N. Bossart; Lin-Fa Wang; Michael N. Flora; Kaw Bing Chua; Sai Kit Lam; Bryan T. Eaton; Christopher C. Broder

2002-01-01

479

New evidence that deformed wing virus and black queen cell virus are multi-host pathogens  

Microsoft Academic Search

The host-range breadth of pathogens can have important consequences for pathogens’ long term evolution and virulence, and play critical roles in the emergence and spread of the new diseases. Black queen cell virus (BQCV) and Deformed wing virus (DWV) are the two most common and prevalent viruses in European honey bees, Apis mellifera. Here we provide the evidence that BQCV

X. Zhang; S. Y. He; J. D. Evans; J. S. Pettis; G. F. Yin; Y. P. Chen

480

Characterization of the Early Steps of Hepatitis C Virus Infection by Using Luciferase Reporter Viruses  

Microsoft Academic Search

The lack of an efficient system to produce hepatitis C virus (HCV) particles has impeded the analysis of the HCV life cycle. Recently, we along with others demonstrated that transfection of Huh7 hepatoma cells with a novel HCV isolate (JFH1) yields infectious viruses. To facilitate studies of HCV replication, we generated JFH1-based bicistronic luciferase reporter virus genomes. We found that

George Koutsoudakis; Artur Kaul; Eike Steinmann; Stephanie Kallis; Volker Lohmann; Thomas Pietschmann; Ralf Bartenschlager

2006-01-01

481

EXISTING ANTIVIRALS ARE EFFECTIVE AGAINST INFLUENZA VIRUSES WITH GENES FROM THE 1918 PANDEMIC VIRUS  

Technology Transfer Automated Retrieval System (TEKTRAN)

The 1918 influenza pandemic caused more than 20 million deaths worldwide. Under biosafety level 3Ag containment, a recombinant influenza virus bearing the 1918 influenza virus hemagglutinin (HA) and neuraminidase (NA) was generated. This virus is highly virulent in mice, pointing to the 1918 HA and...

482

Virus Subtype-Specific Features of Natural Simian Immunodeficiency Virus SIVsmm Infection in Sooty Mangabeys  

Microsoft Academic Search

Simian immunodeficiency virus (SIV) SIVsmm naturally infects sooty mangabeys (SMs) and is the source virus of pathogenic infections with human immunodeficiency virus type 2 (HIV-2) and SIVmac of humans and macaques, respectively. In previous studies we characterized SIVsmm diversity in naturally SIV-infected SMs and identified nine different phylogenetic subtypes whose genetic distances are similar to those reported for the different

Cristian Apetrei; Rajeev Gautam; Beth Sumpter; Anders C. Carter; Thaidra Gaufin; Silvija I. Staprans; J. Else; M. Barnes; R. Cao; S. Garg; J. M. Milush; D. L. Sodora; I. Pandrea; G. Silvestri

2007-01-01

483

Vaccination of Macaques against Pathogenic Simian Immunodeficiency Virus with Venezuelan Equine Encephalitis Virus Replicon Particles  

Microsoft Academic Search

Vaccine vectors derived from Venezuelan equine encephalitis virus (VEE) that expressed simian immuno- deficiency virus (SIV) immunogens were tested in rhesus macaques as part of the effort to design a safe and effective vaccine for human immunodeficiency virus. Immunization with VEE replicon particles induced both humoral and cellular immune responses. Four of four vaccinated animals were protected against disease for

NANCY L. DAVIS; IAN J. CALEY; KEVIN W. BROWN; MICHAEL R. BETTS; DAVID M. IRLBECK; KATHRYN M. MCGRATH; MARY J. CONNELL; DAVID C. MONTEFIORI; JEFFREY A. FRELINGER; RONALD SWANSTROM; PHILIP R. JOHNSON; ROBERT E. JOHNSTON

2000-01-01

484

Real-Time PCR to Identify Variola Virus or Other Human Pathogenic Orthopox Viruses  

Microsoft Academic Search

Background: Variola virus (family Poxviridae, genus Orthopoxvirus) and the closely related cowpox, vaccinia, and monkeypox viruses can infect humans. Efforts are mounting to replenish the smallpox vaccine stocks, optimize diagnostic methods for poxviruses, and de- velop new antivirals against smallpox, because it is feared that variola virus might be used as a weapon of bioterrorism. Methods: We developed an assay

Natale Scaramozzino; Audrey Ferrier-Rembert; Anne-laure Favier; Corinne Rothlisberger; Stephane Richard; Jean-Marc Crance; Hermann Meyer; Daniel Garin

2007-01-01

485

Virus reactivation in pigs latently infected with a thymidine kinase negative vaccine strain of pseudorabies virus  

Microsoft Academic Search

Summary Attenuated, gene-deletion mutants of pseudorabies virus (PRV) were tested for their ability to establish a reactivatable latent infection in pigs. The viruses (designated A, B, and C) were from each of three vaccines commercially available in the United States. Viruses A and C were similar in that they had genetically engineered gene deletions for thymidine kinase (TK) and glycoprotein

W. L. Mengeling

1991-01-01

486

Leukemogenicity and cell transformation mechanisms in vitro by Gross murine leukemia virus: analysis of virus subpopulations.  

PubMed Central

The leukemogenic activity of Gross murine leukemia virus adapted to rats was tested in W/Fu rats and NIH/Swiss mice. All animals infected with this virus developed thymic and nonthymic T-cell leukemia with a short latency period. It was observed that cell-free extracts from thymic lymphoma tissue of mice and rats, induced by either Gross murine leukemia virus or Gross murine leukemia virus adapted to rats, consisted of both small-plaque-forming and large-plaque-forming viruses, as determined by the XC plaque test. MCF-type virus was found in these virus complexes. Transformed cell foci were induced in SC-1 cell layers by double infection of the cloned MCF-type virus and an ecotropic virus. SC-1 cells containing transformed cell foci were shown to be tumorigenic upon inoculation into nude mice. The formation of transformed cell foci in mink lung cells was also observed after double infection with the cloned MCF-type virus and a xenotropic virus. The possible mechanism of leukemogenesis by endogenous viruses is discussed. Images

Hamada, K; Yanagihara, K; Kamiya, K; Seyama, T; Yokoro, K

1981-01-01

487

Mucosal Model of Immunization against Human Immunodeficiency Virus Type 1 with a Chimeric Influenza Virus  

Microsoft Academic Search

Previously, we constructed a chimeric influenza virus that expresses the highly conserved amino acid sequence ELDKWA of gp41 of human immunodeficiency virus type 1 (HIV-1). Antisera elicited in mice by infection with this chimeric virus showed neutralizing activity against distantly related HIV-1 isolates (T. Muster, R. Guinea, A. Trkola, M. Purtscher, A. Klima, F. Steindl, P. Palese, and H. Katinger,

THOMAS MUSTER; BORIS FERKO; ANNELIES KLIMA; MARTIN PURTSCHER; ALEXANDRA TRKOLA; PETRA SCHULZ; ANDREAS GRASSAUER; OTHMAR G. ENGELHARDT; ADOLFO GARCIA-SASTRE; PETER PALESE; ANDHERMANN KATINGER

488

Role of T Cells in Virus Control and Disease after Infection with Pneumonia Virus of Mice  

Microsoft Academic Search

Infection of mice with pneumonia virus of mice (PVM) is used as a natural host experimental model for studying the pathogenesis of infection with the closely related human respiratory syncytial virus. We analyzed the contribution of T cells to virus control and pathology after PVM infection. Control of a sublethal infection with PVM strain 15 in C57BL\\/6 mice was accompanied

Stefanie Frey; Christine D. Krempl; Annette Schmitt-Graff; Stephan Ehl

2008-01-01

489

Frozen Commodity Shrimp: Potential Avenue for Introduction of White Spot Syndrome Virus and Yellow Head Virus  

Microsoft Academic Search

Since 1992, white spot syndrome virus (WSSV) and yellow head virus (YHV) have caused mortalities in cultured shrimp throughout Asia. By 1995, WSSV was detected in Texas and South Carolina, and the virus has also been recently reported in Central and South America (Nicaragua, Honduras, Guatemala, Panama, Colombia, Peru, and Ecuador). The importation of live infected shrimp is the principal

S. V. Durand; K. F. J. Tang; D. V. Lightner

2000-01-01

490

A Virus Similar to Human Hepatitis B Virus Associated with Hepatitis and Hepatoma in Woodchucks  

Microsoft Academic Search

Particles with properties similar to those associated with human hepatitis B were found in serum from woodchucks with chronic hepatitis and hepatocellular carcinoma. It is suggested that woodchuck hepatitis virus is a second member of a novel class of viruses represented by the human hepatitis B virus.

Jesse Summers; Jo Marie Smolec; Robert Snyder

1978-01-01

491

Complete nucleotide sequence of Kashmir bee virus and comparison with acute bee paralysis virus  

Microsoft Academic Search

The complete nucleotide sequence of a novel virus is presented here together with serological evidence that it belongs to Kashmir bee virus (KBV). Analysis reveals that KBV is a cricket paralysis-like virus (family Dicistroviridae: genus Cripavirus), with a non-structural polyprotein open reading frame in the 59 portion of the genome separated by an intergenic region from a structural polyprotein open

J. R. de Miranda; M. Drebot; S. Tyler; M. Shen; C. E. Cameron; D. B. Stoltz; S. M. Camazine

2004-01-01

492

Investigation of xenotropic murine leukemia virus-related virus (XMRV) in human and other cell lines  

Microsoft Academic Search

Xenotropic murine leukemia virus-related virus (XMRV) was discovered in human prostate tumors and later in some chronic fatigue syndrome (CFS) patients. However, subsequent studies have identified various sources of potential contamination with XMRV and other murine leukemia virus (MLV)-related sequences in test samples. Biological and nucleotide sequence analysis indicates that XMRV is distinct from known xenotropic MLVs and has a

Dhanya K. Williams; Teresa A. Galvin; Hailun Ma; Arifa S. Khan

2011-01-01

493

Marburg virus-like particles protect guinea pigs from lethal Marburg virus infection  

Microsoft Academic Search

Ongoing outbreaks of filoviruses in Africa and concerns about their use in bioterrorism attacks have led to intense efforts to find safe and effective vaccines to prevent the high mortality associated with these viruses. We previously reported the generation of virus-like particles (VLPs) for the filoviruses, Marburg (MARV) and Ebola (EBOV) virus, and that vaccinating mice with Ebola VLPs (eVLPs)

Kelly L Warfield; Dana L Swenson; Diane L Negley; Alan L Schmaljohn; M. Javad Aman; Sina Bavari

2004-01-01

494

Multiplex Real Time PCR For Detection of Wheat Streak Mosaic Virus and Triticum Mosaic Virus  

Technology Transfer Automated Retrieval System (TEKTRAN)

Wheat streak mosaic virus (WSMV) and Triticum mosaic virus (TRIMV) are widespread throughout the southwestern Great Plains states. Using conventional diagnostics such as Enzyme-Linked Immunosorbent Assays (ELISA), these two viruses are commonly found together in infected wheat samples. Methods for m...

495

Human Immunodeficiency Virus-Like Particles Produced by a Vaccinia Virus Expression Vector  

Microsoft Academic Search

Infectious retrovirus particles consist of a core structure containing RNA and gag-pol polypeptides surrounded by a lipid membrane studded with env proteins. A recombinant vaccinia virus was designed to express the entire gag-pol precursor protein of the human immunodeficiency virus type 1. Synthesis and processing of gag proteins occurred in mammalian cells infected with this live recombinant virus, and reverse

Velissarios Karacostas; Kunio Nagashima; Matthew A. Gonda; Bernard Moss

1989-01-01

496

Relative Sensitivity of Hepatitis B Virus and Other Hepatotropic Viruses to the Antiviral Effects of Cytokines  

Microsoft Academic Search

We have previously shown that hepatitis B virus (HBV) replication is inhibited noncytopathically in the livers of transgenic mice following injection of HBV-specific cytotoxic T lymphocytes (CTLs) or infection with unrelated hepatotropic viruses, including lymphocytic choriomeningitis virus (LCMV) and adenovirus. These effects are mediated by gamma interferon (IFNg), tumor necrosis factor alpha (TNFa), and IFNa\\/b .I n the present study,

HEIKE MCCLARY; RICK KOCH; FRANCIS V. CHISARI; LUCA G. GUIDOTTI

2000-01-01

497

Generation and Characterization of a Recombinant Vesicular Stomatitis Virus Expressing the Glycoprotein of Borna Disease Virus  

Microsoft Academic Search

Borna disease virus (BDV) is an enveloped virus with a nonsegmented negative-strand RNA genome whose organization is characteristic of mononegavirales. However, based on its unique genetics and biological features, BDV is considered to be the prototypic member of a new virus family, Bornaviridae, within the order Mononegavirales. BDV cell entry occurs via receptor-mediated endocytosis, a process initiated by the recogni-

Mar Perez; Roberto Clemente; Clinton S. Robison; E. Jeetendra; Himangi R. Jayakar; Michael A. Whitt; Juan C. de la Torre

2007-01-01

498

HIGH VIRUS TITER IN FEATHER PULP OF CHICKENS INFECTED WITH SUBGROUP J AVIAN LEUKOSIS VIRUS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Subgroup J avian leukosis viruses (ALVs), which are a recombinant virus between exogenous and endogenous ALVs, can spread by either vertical or horizontal transmission. Exogenous and endogenous ALVs, can be detected in feather pulp. In this study, virus titers in feather pulp of chickens infected w...