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)

In 2001 and 2002, 235 outbreaks of bluetongue were observed in the Lazio and Tuscany regions of central Italy. During entomological surveillance Culicoides imicola, the main vector of bluetongue virus in the Mediterranean region, was detected in only 14 of 28 municipalities affected by outbreaks; Culicoides obsoletus was the most abundant species, contributing 83 per cent of individuals in catches, whereas C. imicola contributed only 2 per cent. In affected municipalities the maximum catch of C. obsoletus was 18,000 specimens, compared with 54 of C. imicola. In October 2002 bluetongue virus serotype 2 was isolated from a single pool of wild-caught, non-blood-engorged parous C. obsoletus inoculated on to BHK-21 cells. Its identity was confirmed by reverse transcriptase-PCR.
Vet Rec 2005 Mar 05
PMID:Identification of Culicoides obsoletus (Diptera: Ceratopogonidae) as a vector of bluetongue virus in central Italy. 1578 18

The human endogenous retrovirus K family (HERV-K) comprises 30 to 50 closely related proviruses, most of which are defective. In contrast to all other human endogenous retroviruses, some HERV-K proviruses have maintained open reading frames for all viral proteins. In addition to the structural proteins Gag and Env and the reverse transcriptase, two regulatory proteins (Rec and Np9) have been described. Malignant melanoma has the highest mortality among skin cancers and is particularly aggressive. To study the expression of HERV-K, a set of seven primers was developed that allows discrimination between full-length and spliced mRNA and mRNA from deleted and undeleted proviruses. Expression of full-length mRNA from deleted and undeleted proviruses was detected in all human cells investigated. Expression of spliced env and rec was detected in a teratocarcinoma cell line, in 45% of the metastatic melanoma biopsies, and in 44% of the melanoma cell lines. In normal neonatal melanocytes, spliced rec was detected but not spliced env. Viral proteins were shown to be expressed in primary melanomas, metastases, and melanoma cell lines by immunohistochemistry, immunofluorescence, and Western blot analyses using specific antisera. For the first time, antibodies against HERV-K were found in melanoma patients. Melanomas are, in addition to teratocarcinomas and human breast cancer, the third tumor type with enhanced expression of HERV-K.
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PMID:Expression of human endogenous retrovirus K in melanomas and melanoma cell lines. 1589 8

The human endogenous retrovirus-K encodes two potential tumor proteins, Rec and Np9. Rec is related to the Rev protein of HIV-1 and has been shown to be associated with tumor development in nude mice. Having shown the expression of human endogenous retrovirus-K in human melanomas and melanoma cell lines, tools were developed to allow the expression of the transmembrane envelope, Rec and Np9 mRNA and proteins to be studied in more detail. The expression of spliced env, rec and np9 was investigated by reverse transcriptase-polymerase chain reaction using a set of primers developed to discriminate between full-length and spliced mRNA. Env-specific, Rec-specific and Np9-specific antisera were produced, characterized and used to study protein expression in melanomas and melanoma cell lines by immunohistochemistry, immunofluorescence and Western blot analyses. Existence of human endogenous retrovirus-K Rec and Np9-specific antibodies in the sera of melanoma patients were analyzed by Western blot of immunofluorescence studies. The expression of both spliced env and rec mRNA was detected in 39% of the melanomas and in 40% of the melanoma cell lines and np9 mRNA was detected in 29 and 21%, respectively. In normal neonatal melanocytes, spliced rec mRNA was detected in the absence of spliced env mRNA. Using antisera specific for Rec and Np9, Rec protein was found in 14% of the melanomas but Np9 in none. In addition, cell surface expression of the putatively immunosuppressive transmembrane envelope protein and release of virus particles were shown. Antibodies specific for neither Rec nor Np9 were detected. The transmembrane envelope protein, Rec and Np9 proteins are expressed in melanoma cells with a pattern similar to that seen in teratocarcinoma cell lines. Additional experiments are needed to determine their involvement, if any, in cell proliferation and tumor progression.
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PMID:Expression of the human endogenous retrovirus-K transmembrane envelope, Rec and Np9 proteins in melanomas and melanoma cell lines. 1671 69

An idea to use 4'-C-substituted-2'-deoxynucleoside derivatives was proposed based on a working hypothesis to solve the problems of existing acquired immune deficiency syndrome chemotherapy (highly active antiretroviral therapy). Subsequent studies have successfully proved the validity of the idea and resulted in the development of 2'-deoxy-4'-C-ethynyl-2-fluoroadenosine, a nucleoside reverse transcriptase inhibitor, which is highly potent to all human immunodeficiency viruses type 1 (HIV-1s) including multidrug-resistant HIV-1 and has a low toxicity.
Chem Rec 2006
PMID:2'-deoxy-4'-C-ethynyl-2-fluoroadenosine, a nucleoside reverse transcriptase inhibitor, is highly potent against all human immunodeficiency viruses type 1 and has low toxicity. 1679 5

Coronavirus-positive samples of faeces collected in an Austrian animal shelter from 12 cats and 10 dogs were analysed by reverse transcriptase-pcr with primers amplifying a segment of the M protein gene, and by sequence analysis. In addition, the samples were subjected to S gene typing, using primers that differentiated between feline coronavirus (fcov) types I and II. A phylogenetic analysis of the M gene sequences revealed not only clearly segregating canine coronavirus (ccov) in the dogs, typical ccov sequences and the recently described fcov-like ccov, but also at least two genetic clusters of fcov in the cats, one species-specific, the other more closely related to fcov-like ccov. The M gene sequences of these new feline strains had at most 88 per cent identity with the fcov-like ccov strain 259/01 and only up to 85 per cent with any fcov sequence available in GenBank. In the phylogenetic tree they occupy an intermediate position between feline and canine coronaviruses.
Vet Rec 2006 Aug 05
PMID:M gene analysis of atypical strains of feline and canine coronavirus circulating in an Austrian animal shelter. 1689 24

There were 2030 designated cases of foot-and-mouth disease (FMD) during the course of the epidemic in the UK in 2001 (including four from Northern Ireland). Samples from 1720 of the infected premises (IPs) were received in the laboratory and examined for either the presence of FMD virus (virological samples from 1421 IPs) or both FMD virus and antibody (virological and serological samples from 255 IPs) or antibody alone (from 44 IPs). The time taken to issue final diagnostic results ranged from a few hours in cases in which positive results were obtained by ELISA on epithelia containing sufficient virus to be detected, to several days for samples containing small amounts of virus requiring amplification through cell culture, negative samples or samples tested for antibody. Two subsets of samples were analysed retrospectively by real-time reverse transcriptase-PCR (RT-PCR); first, epithelia that were negative by both ELISA and virus isolation (VI) in cell culture, and secondly, samples that were negative by ELISA on epithelial suspension but positive by VI. There was broad agreement between the RT-PCR and VI/ELISA combined, except that the RT-PCR procedure did not detect a group of related virus isolates from Wales. These viruses had evidently evolved during the epidemic and had a nucleotide substitution in the RT-PCR probe site, which prevented them from being detected by the routine diagnostic probe. No evidence of FMD virus, antibody or nucleic acid was found in approximately 23 per cent (390 of 1730) of IPs from which samples were received, suggesting that the incidence of FMD during the outbreak may have been over-reported.
Vet Rec 2006 Sep 16
PMID:Comparisons of original laboratory results and retrospective analysis by real-time reverse transcriptase-PCR of virological samples collected from confirmed cases of foot-and-mouth disease in the UK in 2001. 1698 May 22

This study investigated the effects of the vaccination of rams with a serotype 2 bluetongue virus vaccine on the quality of their semen. One group of 23 rams was vaccinated on days 0 and 47, and 23 rams were left unvaccinated. Samples of blood, serum and semen were collected regularly in order to detect the virus genome, and to compare the quality of the semen from the vaccinated and unvaccinated rams. Segment 10 of the genome of the vaccine strain was detected in the blood of the vaccinated animals by reverse transcriptase-PCR (RT-PCR) on days 7, 13 and 19 after the first vaccination, but no virus was isolated from the RT-PCR-positive blood or from any of the semen samples from the vaccinated animals. There was a significant decrease in the concentration and motility of the spermatozoa and an increase in the proportion of abnormal and dead spermatozoa after the first vaccination; however, after the second vaccination only smaller, non-significant changes were observed. On day 69, the quality of the semen of the vaccinated animals was not significantly different from that of the controls.
Vet Rec 2007 Mar 31
PMID:Transient adverse effects of an attenuated bluetongue virus vaccine on the quality of ram semen. 1740 Sep 1

During a field study in Zimbabwe, clinical specimens were collected from 403 cattle in six herds, in which the history of foot-and-mouth disease (FMD) vaccination and infection appeared to be known with some certainty. Five herds had reported outbreaks of disease one to five months previously but clinical FMD had not been observed in the sixth herd. A trivalent vaccine (South African Territories [SAT] types 1, 2 and 3) had been used in some of the herds at various times either before and/or after the recent outbreaks of FMD. The primary aim of this study was to evaluate the performance of serological tests for the detection of SAT-type FMD virus infection, particularly elisas for antibodies to non-structural proteins (NSPs) of FMD virus and solid phase competition ELISAS (SPCEs) for serotypes SAT1 and SAT2. Secondary aims were to examine NSP seroconversion rates in cattle that had been exposed to infection and to compare virus detection rates by virus isolation and real-time reverse transcriptase-PCR (rtRT-PCR) tests on both oesophagopharyngeal fluids and nasopharyngeal brush swabbings. In addition, the hooves of sampled animals were examined for growth arrest lines as clinical evidence of FMD convalescence. Laboratory tests provided evidence of FMD virus infection in all six herds; SAT2 viruses were isolated from oesophagopharyngeal fluids collected from two herds in northern Zimbabwe, and SAT1 viruses were isolated from three herds in southern Zimbabwe. Optimised rtRT-PCR was more sensitive than virus isolation at detecting FMD virus persistence and when the results of the two methods were combined for oesophagopharyngeal fluids, between 12 and 35 per cent of the cattle sampled in the convalescent herds were deemed to be carriers. In contrast, nasopharyngeal swabs yielded only two virus-positive specimens. The overall seroprevalence in the five affected herds varied with the different NSPS from 56 per cent to 75 per cent, compared with 81 per cent and 91 per cent by homologous SPCE and virus neutralisation tests respectively. However, if serological test results were considered only for the cattle in which persistent infection with FMD virus had been demonstrated, 70 to 90 per cent scored seropositive in the different NSPs.
Vet Rec 2007 May 12
PMID:Evaluation of laboratory tests for SAT serotypes of foot-and-mouth disease virus with specimens collected from convalescent cattle in Zimbabwe. 1749 71

Three alpacas (Vicugna pacos) aged two to 22 months with a history of illthrift and diarrhoea were examined postmortem, and tissues were collected for histology, including immunohistochemical labelling for pestivirus antigen, virus isolation and TaqMan reverse transcriptase-pcr assay. Blood samples from two clinical cases and the remaining herd members were tested for bovine viral diarrhoea virus (bvdv) antibody by serum neutralisation, antigen detection and pcr assay. The three affected alpacas were positive for bvdv by pcr of splenic tissue and/or heparinised blood. Non-cytopathic bvdv was isolated from several tissues and plasma of two of the alpacas. dna sequencing and phylogenetic analysis of the viral genome from the pcr product showed that the bvdv was of subgenotype 1b. Immunohistochemical examination of brain tissue was positive in two cases, consistent with a persistent infection. bvdv antibodies were detected in 16 of 25 clinically unaffected alpacas. There was no evidence of persistent infection in the in-contact animals. The source of the infection was not determined.
Vet Rec 2007 Jul 21
PMID:Bovine viral diarrhoea virus infection of alpacas (Vicugna pacos) in the UK. 1765 35

Four poll Dorset sheep and four Holstein-Friesian cattle were infected with the northern European strain of bluetongue virus (BTV), BTV-8, to assess its pathogenicity in UK breeds. The time course of infection was monitored in both species by using real-time reverse transcriptase-PCR (RT-PCR), conventional RT-PCR and serology. Two of the sheep developed severe clinical signs that would have been fatal in the field; the other two were moderately and mildly ill, respectively. The cattle were clinically unaffected, but had high levels of viral RNA in their bloodstream. Real-time RT-PCR detected viral RNA as early as one day after infection in the cattle and three days after infection in the sheep. Antibodies against BTV were detected by six days after infection in the sheep and eight days after infection in the cattle. Postmortem examinations revealed pathology in the cattle that was more severe than suggested by the mild clinical signs, but the pathological and clinical findings in the sheep were more consistent.
Vet Rec 2007 Aug 25
PMID:Clinical signs and pathology shown by British sheep and cattle infected with bluetongue virus serotype 8 derived from the 2006 outbreak in northern Europe. 1772 Sep 61


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