1. ???virus?? - ??, ??; ???, ????; Inaba, Noriyuki; INABA, Noriyuki
Viral infections during pregnancy are of concern not only in terms of maternal morbidity and the possibility of attendant fetal loss, but because certain agents are capable of crossing the placenta and inducing chronic perinatal infections that have serious pathogenic potential for the fetus and newborn. In this paper, pregnancy and viral infections are reviewed mainly from the aspects of: 1. fundamental knowledge of virology 2. epidemiology 3. diagnosis 4. possible impact of maternal viral infections on themselves, fetuses and offspring 5. trial prevention and treatment. The most important viruses in connection with pregnancy are rubella, cytomegalovirus, hepatitis B virus...

2. Virus fitopatógenos transmisibles por semilla en judía tipo ¿granja asturiana¿ - González, Ana J.
Se analizaron muestras de semillas de judía tipo "granja asturiana" -desde 1994- mediante técnicas ELISA para detectar las virosis asociadas. El virus que con mayor frecuencia se asoció a este tipo de semilla fue el virus del mosaico común de la judía (BCMV), seguido del virus del mosaico del pepino (CMV). El virus del bronceado del tomate (TSWV) tuvo importancia en los cultivos del 94 y 95 en la variedad Bonafema. La presencia de otros virus fue testimonial. La transmisión del virus BCMV en la variedad Andecha, tras el análisis de 10.844 semillas procedentes de plantas infectadas, se situó en...

3. Viruses 1950. Proceedings of a conference on the similarities and dissimilarities between viruses attacking animals, plants, and bacteria, respectively. Held at the California Institute of Technology, Mar. 20-22, 1950. With contributions by J.G. Bald [and others] Edited by M. Delbrück. - Conference on the Similarities and Dissimilarities between Viruses Attacking Animals, Plants and Bacteria,
147 p.

4. Virus Diversity and the Emergence of Dengue - Thu, Hlaing Myat
The aims of this study were to investigate the role of the diversity of dengue virus populations in changing patterns of virus transmission and disease. Prior to the commencement of this study, dengue 2 virus (DENV-2) had been associated most frequently with severe disease, so the study commenced with this serotype. Because it was not possible to quantitate diversity in the entire 11 kb of the viral genome, the study focussed on the envelope (E) gene, because the E protein is the major protein on the surface of the virion and thus might be under strong selective pressure from the...

5. Virus Diversity and the Emergence of Dengue - Thu, Hlaing Myat
The aims of this study were to investigate the role of the diversity of dengue virus populations in changing patterns of virus transmission and disease. Prior to the commencement of this study, dengue 2 virus (DENV-2) had been associated most frequently with severe disease, so the study commenced with this serotype. Because it was not possible to quantitate diversity in the entire 11 kb of the viral genome, the study focussed on the envelope (E) gene, because the E protein is the major protein on the surface of the virion and thus might be under strong selective pressure from the...

6. Real-Time Virus Detection System Using iNetmon Engine - Sureswaran Ramadass; Azlan Bin Osman; Rahmat Budiarto; N. Sathiananthan; Ng Chin Keong; Choi Sy Jong
The fundamental problem with any network administration systems today is its ability to cope with the rising amount of virus intrusions. Currently available systems are only able to detect a virus after the network has been infected, therefore its non-real time. Depending on the malicious activities of the viruses, the detection will be carried out. Herewith, we are proposing a Real-Time Virus Detection system, which detects the arrival of virus intruders at the network layer rather than at the application layer. In this paper, we present an overview of the system design, which uses the iNetmon engine, Virus parser, Virus...

7. Detecção e análise molecular do vírus da cinomose canina - Pozza, Michel
O vírus da Cinomose Canina é uma doença multisistêmica cosmopolita com altos índices de mortalidade que afeta cães domésticos e diversos animais selvagens. Desde a década de 1960 tem sido controlado através de campanhas de vacinação porém, atualmente tem ocorrido o surgimento de diversos casos, em todo o mundo, de cães vacinados que desenvolveram a doença. O diagnóstico da Cinomose Canina é difícil e tem sido feito habitualmente através dos sinais clínicos da doença. No Brasil, bem como no Rio Grande do Sul somos carentes de dados sobre a epidemiologia e distribuição da Cinomose Canina. O objetivo deste estudo foi...

8. Characterization of Vesicular Stomatitis Virus Strains with Adaptability - Presloid, John B.
Vesicular stomatitis virus (VSV) is an RNA virus commonly used for the study of RNA virus evolution. Like other RNA viruses, VSV has a high mutation rate, averaging one mutation per genome per round of replication. This high mutation rate leads to a genetically heterogeneous population; each produced virus will have at least one new mutation. This collection of mutants is termed a quasispecies. Bottlenecking of a population results in the fixation of random mutations, which are more likely to be deleterious than those that are fixed through selection. Previous studies have found bottlenecked virus strains with adaptability defects that...

9. Purification and characterization of infectious myonecrosis virus of penaeid shrimp - POULOS, B; TANG, K; PANTOJA, C; BONAMI, Jean-Robert; LIGHTNER, D
The causative agent of myonecrosis affecting cultured Penaeus vannamei in Brazil was demonstrated to be a virus after purification of the agent from infected shrimp tissues. Purified viral particles were injected into specific pathogen-free P. vannamei, resulting in a disease that displayed the same characteristics as those found in the original shrimp used for purification. The virus was named infectious myonecrosis virus (IMNV). The viral particles were icosahedral in shape and 40 nm in diameter, with a buoyant density of 1(.)366 g ml(-1) in caesium chloride. The genome consisted of a single, double-stranded (dsRNA) molecule of 7560 bp. Sequencing of...

10. Identificación de virus que se transmiten a través de semillas de caraota (Phaseolus vulgaris L.) y fríjol (Vigna unguiculata (L.) Walpers) en áreas productoras de Venezuela - Peña, Z.; Trujillo, G.
Para conocer la incidencia de virus que se transmiten a través de la semilla en áreas productoras de caraota y fríjol, se evaluaron 53 materiales usados como semilla. Se seleccionaron aislamientos virales provenientes de las semillas sembradas en umbráculo protegido contra insectos; identificándose los aislamientos virales de caraota como: "Colombiana 1", "Colombiana 2" y "Tucutunemo" y el de fríjol como "Ojo negro". Para este estudio se multiplicó el material, se realizaron las pruebas de estabilidad en savia, se estudió la transmisión a través de insectos, se estudió el rango de hospedantes, microscopía electrónica y se realizaron pruebas serológicas con los...

11. UNA virus: first report of human infection in Argentina - Diaz,Luis Adrián; Spinsanti,Lorena Ivana; Almiron,Walter Ricardo; Contigiani,Marta Silvia
Una virus (UNAV), Togaviridae family, is widely distributed in South America, where infections have been detected in mosquitoes and vertebrate hosts (humans, birds and horses). We analyzed human sera from Córdoba inhabitants aged 44 to 89 years and using a neutralization test, we found a prevalence of UNAV antibodies of 3.8% (3/79). The low titers detected suggest past infections probably acquired in rural areas of the Province of Córdoba (central Argentina). None sera were found positive for MAYV neutralizing antibodies. This is the first report of human infections by UNAV in Argentina.

12. Metodologías para la extracción de virus provenientes de semillas de caraota (Phaseolus vulgaris L.) y frijol (Vigna unguiculata (L.) Walp.). - Peña P., Z. M.; Trujillo, G.
En Venezuela desde 1980 se ha señalado la presencia de microorganismos patógenos como bacteria, hongos y virus en la mayoría de las semillas de leguminosas estudiadas, incluye: comercial, registrada, fundación, experimental; y los métodos empleados para garantizar la sanidad de la semilla, no incluyen pruebas que permitan extraer los virus, no existen registros ni conocimiento en general de la introducción de enfermedades virales vía semilla en nuestro país, a pesar de la relevancia de esta forma de transmisión. Más del 50% de las enfermedades importantes en caraota (Phaseolus vulgaris L.) y en fríjol (Vigna unguiculata (L.) Walp.) más de 15 virus, se trasmiten por semillas. Por ello, se tomó...

13. Virus respiratorio sincicial bovino : padronização e comparação de tecnicas sorologicas - Helena Gallicchio Domingues
Neste trabalho foram adaptados e padronizados dois ensaios imunoenzimáticos (dot ELISA e S-ELISA), para auxiliar 110 diagnóstico do vírus respiratório sincicial bovino (BRSV). A amostra vira! padrão, BRSV -25-BR isolada 110 Brasil foi utilizada nos dois ensaios, tendo sido produzida em célula CER e processadas por ultracentrifugação em gradiente descontínuo de sacarose 30-55% (v/v). Foram analisadas 423 amostras de sorosco1etados nos principais centros de bovinocultura do país. as quais foram submetidas ao teste padrão de soroneutralização (SN). onde 67,8% das amostras foram positivas. A técnica de dot-EUSA, utjlizando O.7/µg de proteína purificada por disco, detectou 71,6% deamostras positivas, apresentando uma...

14. Persistent Virus Infection and T Cell Receptor Selection
Human cytomegalovirus (HCMV) is a β-herpesvirus that establishes a life-long presence in the infected host. The adaptive immune response is indispensable in controlling HCMV infection. Consequently, healthy individuals show no or mild symptoms following primary infection. In contrast, immunocompromised individuals who develop primary infection or recrudescence of HCMV can experience severe morbidity, and sometimes mortality. HCMV-specific T cell populations undergo changes in the architecture of their T cell receptor (TCR) repertoire following each episode of viral reactivation. A diverse TCR repertoire is thought to be required to provide the most efficient protection against virus infection. Perturbation to this repertoire, as...

15. Identificación del antígeno del virus de la fiebre porcina clásica en excretas porcinas sólidas y líquidas en una granja del estado de Guanajuato, México - Quezada Monroy, Juan Francisco; Mercado García, María del Carmen; Ramírez Hernández, Gerardo; Martínez Gamba, Roberto; Macías G., Martha
El presente estudio tuvo como objetivo detectar la presencia del virus de fiebre porcina clásica (vFPC) a partir de residuos orgánicos. Se evaluaron un total de 40 muestras del material de cárcamo de recolección, excretas sólidas y líquidos separados, de ocho granjas ubicadas en la región central de México, las cuales tienen implementado un sistema de tratamiento de excretas por medio de un separador de sólidos y líquidos. Todas las muestras se procesaron por medio de las pruebas de inmunofluorescencia directa, inmunoperoxidasa directa y ELISA de captura para evidenciar la presencia del vFPC. Todas las muestras resultaron negativas por las...

16. Objectives - D. Viruses,B. Transduction,C. Conjugation,D. Transposons
D. Ivanowsky, Martinus Beijerinck and Wendell Stanley. 2. List and describe structural components of viruses. 3. Explain why viruses are obligate parasites. 4. Describe three patterns of viral genome replication. 5. Explain the role of reverse transcriptase in retroviruses. 6. Describe how viruses recognize host cells. 7. Distinguish between lytic and lysogenic reproductive cycles using phage T 4 and phage l as examples. 8. Outline the procedure for measuring phage concentration in a liquid medium. 9. Describe several defenses bacteria have against phage infection. 10. Using viruses with envelopes and RNA viruses as examples, describe variations in replication cycles of animal viruses. 11. Explain how viruses may cause disease symptoms and describe...

17. Hemagglutination by Rabies Virus - Kuwert, Ernst; Wiktor, Tadeusz J.; Sokol, Frantisek; Koprowski, Hilary
Goose erythrocytes were agglutinated by five strains of rabies virus grown in monolayer cell cultures at pH 6.4 and at 0 to 4 C. Hemagglutination was not affected by the cell type in which the virus was grown. Prerequisites for occurrence of hemagglutination are absence of hemagglutination inhibitors (such as those contained in bovine serum) and a relatively high virus concentration (> 106 plaque-forming units of virus per ml). “Soluble” hemagglutinin was not present in crude preparations of extracellular virus. Treatment of purified preparations of extracellular virus with Tween 80 and ether did not result in release of a “soluble”...

18. Virus-Dependent Glycosylation - Sefton, Bartholomew M.
The oligosaccharides of the membrane glycoproteins of Sindbis virus, vesicular stomatitis virus, and Rous sarcoma virus were compared on the basis of apparent size and sugar composition. It appears that each virus acquires a different set of oligosaccharides during growth in a single type of cell.

19. Hemagglutination by Rabies Virus - Kuwert, Ernst; Wiktor, Tadeusz J.; Sokol, Frantisek; Koprowski, Hilary
Goose erythrocytes were agglutinated by five strains of rabies virus grown in monolayer cell cultures at pH 6.4 and at 0 to 4 C. Hemagglutination was not affected by the cell type in which the virus was grown. Prerequisites for occurrence of hemagglutination are absence of hemagglutination inhibitors (such as those contained in bovine serum) and a relatively high virus concentration (> 106 plaque-forming units of virus per ml). “Soluble” hemagglutinin was not present in crude preparations of extracellular virus. Treatment of purified preparations of extracellular virus with Tween 80 and ether did not result in release of a “soluble”...

20. Virus-Dependent Glycosylation - Sefton, Bartholomew M.
The oligosaccharides of the membrane glycoproteins of Sindbis virus, vesicular stomatitis virus, and Rous sarcoma virus were compared on the basis of apparent size and sugar composition. It appears that each virus acquires a different set of oligosaccharides during growth in a single type of cell.

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