Virus Norwalk
Mostrando 13-24 de 136 artigos, teses e dissertações.
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13. Detection of Norwalk virus in stool by polymerase chain reaction.
A method of reverse transcription (RT) and polymerase chain reaction (PCR) for the detection of Norwalk virus in human stools was developed. A cationic detergent, cetyltrimethylammonium bromide, was found to effectively remove from stool extracts factors that inhibit the RT-PCR assay. The specificities of the tests were shown by hybridization of the amplifie
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14. Reduction of Norwalk Virus, Poliovirus 1, and Bacteriophage MS2 by Ozone Disinfection of Water
Norwalk virus and other human caliciviruses (noroviruses) are major agents of gastroenteritis, and water is a major route of their transmission. In an effort to control Norwalk virus in drinking water, Norwalk virus reduction by bench-scale ozone disinfection was determined using quantitative reverse transcription (RT)-PCR for virus assays. Two other enteric
American Society for Microbiology.
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15. Detection of Norwalk virus in stool specimens by reverse transcriptase-polymerase chain reaction and nonradioactive oligoprobes.
A reverse transcriptase (RT)-polymerase chain reaction (PCR)-oligoprobe (OP), or RT-PCR-OP, method was developed for the detection of the Norwalk virus, which causes acute, epidemic gastroenteritis, in stool specimens. The Norwalk virus genome regions encoding the following two proteins were amplified by RT-PCR: the RNA polymerase (260-bp product) and a puta
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16. Norwalk-like viruses: demonstration of genomic diversity by polymerase chain reaction.
A reverse transcription-polymerase chain reaction (RT-PCR) amplification procedure was developed for the detection of Norwalk-like viruses in fecal specimens. Ninety-nine fecal specimens collected in the United Kingdom and containing small round-structured virus particles as determined by electron microscopy were tested. They came from 50 outbreaks and 16 sp
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17. Detection of Norwalk virus antibodies and antigen with a biotin-avidin immunoassay.
Biotin-avidin immunoassays (BAIs) were developed to detect Norwalk virus antigen and to measure Norwalk virus antibody. The BAI detected Norwalk virus infections by a fourfold titer rise in antibody in sera or by antigen in stool, with a sensitivity similar to or greater than that of the radioimmunoassay (RIA), and the BAI appeared to be more sensitive than
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18. Norwalk Virus N-Terminal Nonstructural Protein Is Associated with Disassembly of the Golgi Complex in Transfected Cells
Norwalk virus is the prototype strain for members of the genus Norovirus in the family Caliciviridae, which are associated with epidemic gastroenteritis in humans. The nonstructural protein encoded in the N-terminal region of the first open reading frame (ORF1) of the Norwalk virus genome is analogous in gene order to proteins 2A and 2B of the picornaviruses
American Society for Microbiology.
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19. Norwalk virus antigen and antibody response in an adult volunteer study.
To better define the optimum timing of specimen collection and identify alternate ways to diagnose Norwalk virus outbreaks, we looked at the timing of the antibody response and virus excretion in a human volunteer study. The Norwalk virus antibody titers and antigen in stool specimens were examined by biotin-avidin immunoassay. Our data suggest that in epide
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20. Detection of immunoglobulin M (IgM), IgA, and IgG Norwalk virus-specific antibodies by indirect enzyme-linked immunosorbent assay with baculovirus-expressed Norwalk virus capsid antigen in adult volunteers challenged with Norwalk virus.
Pre- and postexposure sera collected from 17 adult volunteers challenged with Norwalk virus as described previously (D. Y. Graham, X. Jiang, T. Tanaka, A. Opekun, P. Madore, and M. K. Estes, J. Infect. Dis. 170:34-43, 1994) were examined for Norwalk virus-specific immunoglobulin M (IgM), IgA, and IgG by indirect enzyme-linked immunosorbent assays with recomb
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21. Identification of minireovirus as a Norwalk-like virus in pediatric patients with gastroenteritis.
In 1977, 30- to 32-nm virus-like particles, named minireovirus because of their unique morphologic appearance, were detected by electron microscopy in the stools of infants and young children with gastroenteritis. Sequence analysis of approximately 2,800 consecutive bases derived from overlapping PCR clones of a recent minireovirus clinical isolate showed 52
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22. Immune response and prevalence of antibody to Norwalk enteritis virus as determined by radioimmunoassay.
A solid-phase microtiter radioimmunoassay was established for the detection of Norwalk virus and its antibody, with clinical materials from human volunteers previously studied in Massachusetts as reagents. A study of 308 Massachusetts residents showed that serum antibody to Norwalk agent was rarely present during childhood but was detectable in approximately
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23. Expression and Self-Assembly of Grimsby Virus: Antigenic Distinction from Norwalk and Mexico Viruses
A cDNA obtained from Grimsby virus (GRV), a Norwalk-like virus, purified from a stool sample of a symptomatic adult associated with a gastroenteritis outbreak in the United Kingdom, was used to obtain the complete nucleotide sequence of the second open reading frame (ORF2). The ORF2 sequence of GRV predicts a capsid of 539 amino acids (aa) which exhibits aa
American Society for Microbiology.
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24. Immunoglobulin M responses to the Norwalk virus of gastroenteritis.
Eighty-seven serum specimens from 20 human subjects experimentally inoculated one or more times with Norwalk virus were quantitatively examined for virus-specific immunoglobulin M (IgM). A sensitive and specific radioimmunoassay for anti-Norwalk virus blocking activity was applied to whole serum and to separate IgM and IgG fractions obtained by sucrose densi