Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.7.49 (reverse transcriptase)
 31,746 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A 4-year-old aboriginal boy developed encephalitis due to Murray Valley encephalitis virus (MVE) following an earlier infection with Kunjin virus (KUN). The illness was severe, resulting in cerebral atrophy and profound physical and intellectual disability. The earlier KUN infection complicated his serological profile and delayed antibody responses to MVE. By contrast, the reverse transcriptase-polymerase chain reaction (RT-PCR) assay detected MVE in serum 3 days after the onset of illness and 4 days before the appearance of MVE-specific IgM. We suggest that MVE-specific RT-PCR provides rapid and specific diagnosis of MVE and should be used more widely for the diagnosis of acute viral encephalitis in cases originating from flavivirus endemic areas.
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PMID:Early diagnosis of Murray Valley encephalitis by reverse transcriptase-polymerase chain reaction. 1074 Aug 7

The development of single, sensitive, fluorogenic reverse transcriptase-polymerase chain reaction (TaqMan) assays were required for the rapid and specific detection of three encephalitic viruses found in the Australasian region, namely; Japanese encephalitis virus (JEV), Murray Valley encephalitis virus (MVEV), and Kunjin virus (KUNV). Primers and a fluorogenic probe were individually designed to be complementary to a nucleotide region encompassing the 3' terminus of the nonstructural (NS) 5 gene and a portion of the 3' untranslated region (NS5-3'UTR) of each of the viral genomes respectively. Synthetically produced primer and probe controls were developed to minimize the likelihood of contamination and generation of false positives. Viral RNA from singly infected mosquitoes could be detected in pools of 1000 mosquitoes and positive mosquito pools collected from the field have been identified using each assay, indicating a high level of sensitivity and suitability for use in mosquito surveillance programs. In addition, the JEV TaqMan assay has been used to detect successfully viral RNA in sentinel pig serum samples. These assays potentially offer superior and timely detection of encephalitic viruses from surveillance samples, which is essential for the rapid implementation of vector control measures and continued monitoring of virus activity in the Australasian region.
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PMID:Detection of Australasian Flavivirus encephalitic viruses using rapid fluorogenic TaqMan RT-PCR assays. 1504 Dec 13

Biological transmission of arboviruses to a vertebrate host occurs when virions are expelled along with saliva during blood feeding by a hematophagous arthropod. We undertook experiments to determine whether mosquitoes expectorate flaviviruses in their saliva while sugar feeding. Batches of Culex annulirostris Skuse and Culex gelidus Theobald (Diptera: Culicidae) were orally infected with Japanese encephalitis (family Flaviviridae, genus Flavivirus, JEV), Kunjin (family Flaviviridae, genus Flavivirus, KUNV; a subtype of West Nile virus), and Murray Valley encephalitis (family Flaviviridae, genus Flavivirus, MVEV) viruses. After a 7-d extrinsic incubation, these mosquitoes were offered sucrose meals via cotton pledgets, which were removed daily and processed for viral RNA by using real-time TaqMan reverse transcriptase-polymerase chain reaction (RT-PCR) assays. JEV, MVEV, and KUNV RNA was detected in all pledgets removed from batches of Cx. gelidus on days 7-14 postexposure. In contrast, detection rates were variable for Cx. annulirostris, with KUNV detected in 0.3 M sucrose pledgets on all days postexposure, and JEV and MVEV detected on 57 and 50% of days postexposure, respectively. Higher concentrations of sucrose in the pledget did not increase virus detection rates. When individual JEV-infected Cx. gelidus were exposed to the sucrose pledget, 73% of mosquitoes expectorated virus with titers that were detectable by TaqMan RT-PCR. These results clearly show that flaviviruses are expectorated by infected mosquitoes during the process of sugar feeding on artificial pledgets. Potential applications of the method for arboviral bioassays and field surveillance are discussed.
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PMID:Expectoration of Flaviviruses during sugar feeding by mosquitoes (Diptera: Culicidae). 1791 18