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Prevalent Genotypes (prevalent + genotype)
Selected AbstractsPrevalence of erythrovirus genotypes in the myocardium of patients with dilated cardiomyopathy,JOURNAL OF MEDICAL VIROLOGY, Issue 7 2008U. Kühl Abstract Parvovirus B19 (PVB19) is a member of the human erythrovirus family detected frequently in endomyocardial biopsies from patients with dilated cardiomyopathy. Human erythroviruses cluster into three genotypes 1,3 which share a high degree of homology between major structural proteins and may cause indistinguishable infections clinically and serologically. In human cardiac tissue erythrovirus genotypes other than PVB19 have not yet been reported. Three hundred seventeen consecutive patients with symptomatic dilated cardiomyopathy (median left ventricular ejection fraction: 28.6%, range 5,45%) who underwent endomyocardial biopsy for the elucidation of the etiology, were analyzed using a new consensus PCR assay designed for the detection of the three erythrovirus genotype sequences. Endomyocardial biopsies of 151 (47.6%) patients were erythrovirus-positive. Genotype 1 specific sequences were detected in 43/151 (28.5%) of positive biopsy samples, whereas genotype 2-specific sequences so far considered rare in human disease and not yet been described in human heart tissue was identified in 108/151 (71.5%) of virus-positive endomyocardial biopsies with a preference in patients above 50 years of age. In spite of younger age, systolic left ventricular dysfunction of genotype 1-positive patients was significantly reduced as compared to genotype 2-positive patients (24.4,±,10.4% vs. 31.0,±,9.5%, P,=,0.0001) at the initial presentation. The data show that two genetically distinct erythrovirus variants with a different age distribution are detectable in endomyocardial biopsies of patients with dilated cardiomyopathy. The erythrovirus genotype 2, not described previously in human heart tissue, is highly prevalent in the heart but the less prevalent genotype 1 is associated with more severe disturbed cardiac function. J. Med. Virol. 80: 1243,1251, 2008. © 2008 Wiley-Liss, Inc. [source] Molecular and serological aspects of HBsAg-negative hepatitis B virus infections in North AmericaJOURNAL OF MEDICAL VIROLOGY, Issue 1 2003C.C. Hsia Abstract A few hepatitis B virus (HBV) infections are characterized by the presence of HBV DNA in serum or liver tissue, or both, in the absence of detectable hepatitis B surface antigen (HBsAg) in serum. However, such infections have rarely been described previously in North American patients. In the present study, 31 hepatocellular carcinoma (HCC) patients from the United States and Canada who had no detectable HBsAg in their serum were studied. In these 31 HBsAg-negative HCC patients, HBV DNA was detected in HCC and/or in adjacent nontumorous liver tissue using nested polymerase chain reaction (PCR) in 5/9 (56%) patients from the United States and in 12/22 (55%) from Canada. The 17 HBV DNA-positive/HBsAg-negative patients from the United States and Canada included 9 without any serological markers for HBV and 8 with detectable antibodies to hepatitis B core antigen. In these patients, HBV genotype C was the most prevalent genotype (11/17; 64%). HBV genotypes have not been previously reported in HCC patients from North America. Replicative intermediate forms of HBV (covalently closed circular HBV DNA) were detected in 2/17 (12%) HBV DNA-positive/HBsAg-negative patients, indicating that at least two of these patients had actively replicating HBV infections. The use of tests to detect HBV DNA permitted the identification of HBV infections in HBsAg-negative HCC patients from North America. Among these patients, those with antibody to hepatitis C virus (HCV) would otherwise have been designated "HCV-associated HCCs" based on serological tests alone. These findings provide a new perspective on determining the possible viral etiologies of HCCs in North America. J. Med. Virol. 70: 20,26, 2003. © 2003 Wiley-Liss, Inc. [source] Distribution of fimA genotypes of Porphyromonas gingivalis in subjects with various periodontal conditionsMOLECULAR ORAL MICROBIOLOGY, Issue 4 2004C. G. Missailidis Fimbria encoded by the gene fimA is considered one of the main factors in the colonization of the oral cavity by Porphyromonas gingivalis. Allelic variation in fimA led to the classification of strains of P. gingivalis into six genotypes. The occurrence of P. gingivalis was determined by polymerase chain reaction using 16S rRNA primers in 302 subgingival samples obtained from 102 Brazilian subjects exhibiting different periodontal conditions. Distribution of fimA genotypes was assessed in 146 P. gingivalis positive samples by polymerase chain reaction using primers pairs homologous to the different fimA genes. P. gingivalis was detected in 51 of 57 (89.4%) patients with periodontal attachment loss, in six of 20 gingivitis patients (30.0%) and in two of 25 (8.0%) subjects with a healthy periodontium. Variant type II was the only type detected in 53 sites (39.3%), distributed among 19 periodontitis patients (37.3%) and in one patient with no periodontal destruction. Type Ib was the second most prevalent genotype in periodontitis patients (19.6%). Genotype V was not detected in the studied population. Type IV was the most commonly type found among gingivitis patients, either alone or in combination with other genotypes. Multiple genotypes were detected in nine sites (6.1%). A fimA genotype was not identified in 26 sites (17.8%) of 146 sites positive for P. gingivalis, suggesting that other alleles of fimA not yet sequenced may be prevalent in this population. These data demonstrated that P. gingivalis type II strains followed by type Ib are more prevalent in periodontitis patients from a multiracial population in Brazil, suggesting an increased pathogenic potential of these types. [source] Human papillomavirus (HPV) genotype distribution in invasive cervical cancers in France: EDITH study ,INTERNATIONAL JOURNAL OF CANCER, Issue 2 2008Jean-Luc Prétet Abstract Invasive cervical cancer (ICC) remains a significant cause of morbidity and mortality in France. Since human papillomavirus (HPV) is the necessary cause of ICC, the aim of this study was to assess the type-specific prevalence of HPV in ICC in France in order to locally evaluate the potential benefit of an HPV 16/18 L1 virus-like particles (VLP) vaccination. A total of 516 histological specimens collected in 15 centers were analyzed. Among them, 86% had a diagnosis of squamous cell carcinoma (SCC) whereas 14% were adenocarcinomas (ADC). HPV genotyping was performed using the INNO-LiPA assay allowing the specific detection of 24 HPV genotypes both high risk (HR) and low risk (LR). The overall HPV prevalence in ICC was 97%. The most prevalent genotypes were HPV 16 (73%) and HPV 18 (19%) followed by HPV 31 (7%), 33, 68, 45, 52 and 58 (4.1,2.3%). HPV 16 and/or 18 were associated with 82% of ICC, 10% being HPV 16 and 18 coinfections. While HPV 16 was the most prevalent type in both SCC (74%) and ADC (64%), HPV 18 was by far more prevalent in ADC (37%) compared to SCC (16%; p < 0.001). Multiple infections with at least two different HR HPV genotypes were observed in 22% of ICC. Given the high HPV 16/18 prevalence and taking into account possible production of crossneutralizing antibodies against other HPV types, HPV 16/18 L1 VLP vaccination would be expected to significantly reduce the burden of ICC in France. © 2007 Wiley-Liss, Inc. [source] Epidemiology of enterovirus types causing neurological disease in Austria 1999,2007: Detection of clusters of echovirus 30 and enterovirus 71 and analysis of prevalent genotypesJOURNAL OF MEDICAL VIROLOGY, Issue 2 2009Birgit Ortner Abstract Between 1999 and 2007 1,388 stool specimens from patients with acute flaccid paralysis or aseptic meningitis were submitted to the Austrian reference laboratory for poliomyelitis. Samples (201) yielded non-poliovirus enterovirus in culture. One hundred eighty-one viruses were available for typing and 78 isolates which remained serologically untyped were further analyzed by CODEHOP-PCR and sequencing of the VP1 gene and the 5,-untranslated region (5,-UTR). Typing revealed an Echovirus 30 outbreak in northwestern Austria in 2000, which was in accordance with the situation in Europe, and no dramatic seasonal changes of Coxsackie viruses were observed. In 2002/2003 a small outbreak of enterovirus 71 (EV71), affected 12 patients in the province of Styria. This virus was identified as genotype C1 and appeared to be genetically distinct from the isolates observed in 2001/2002 in Vienna. In 2004 two unrelated cases occurred in Lower Austria, which were identified as genotype C4, which has been described associated with high mortality most recently in China. In contrast to the situation in Asia the detected EV71 cases were not associated with hand,foot,mouth disease, but with serous meningitis only. This was surprising as a recent publication suggested a reduced neurovirulence of C1 genotype in children in Norway, presumably due to alterations in 5,-UTR and polymerase gene. However, comparing the 5,-UTR of the Austrian isolates and established virulent reference strains to the Norwegian isolate and an attenuated EV71 laboratory strain we did not find an indication that the genotype C1 possesses a RNA structure in its 5,-UTR leading to reduced neurovirulence. J. Med. Virol. 81:317,324, 2009. © 2008 Wiley-Liss, Inc. [source] Evidence for predominant clones in a cyclically parthenogenetic organism provided by combined demographic and genetic analysesMOLECULAR ECOLOGY, Issue 12 2000L. Haack Abstract Aphids are particularly interesting models in the study of genetic and demographic components of plant adaptation because of their breeding system which combines parthenogenesis and sexual reproduction (i.e. cyclical parthenogenesis), and the frequent emergence of host-adapted races reported in this group. In this paper, patterns of host adaptation were assessed on local populations of the aphid Sitobion avenae by following their demographic and genetic structure in a maize field for two consecutive years. The existence of putative generalist (polyphagous) or specialized (host-adapted) genotypes was also investigated by comparing the genotypic distribution of this aphid on maize and other cultivated host plants, using five microsatellite loci. Although population dynamics revealed strong variation in aphid abundance during the colonization period on maize, two genotypes identified at seven additional microsatellite loci were predominant and exhibited stable frequencies over cropping season and between years. Based on present and earlier studies, these two prevalent genotypes were shown to survive on different host plants other than maize, to colonize large geographical zones and to persist parthenogenetically for several years. All these data strongly suggest that these two genotypes are asexual generalist clones that could have been favoured by agricultural practices encountered in western Europe. Besides these two clones, a continual replacement of rare genotypes was observed on maize in both years. Hypotheses involving selection via aphid,plant interactions and natural enemies were proposed for explaining the disappearance of these genotypes on maize. [source] GENOTYPE AND ALLELE FREQUENCIES OF N -ACETYLTRANSFERASE 2 AND GLUTATHIONE S -TRANSFERASE IN THE IRANIAN POPULATIONCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 11 2007Anahita Torkaman-Boutorabi SUMMARY 1.,Xenobiotic-metabolizing enzymes constitute an important line of defence against a variety of carcinogens. Many are polymorphic, constituting the basis for the wide interindividual variation in metabolic capacity and possibly a source of variation in the susceptibility to chemical-induced carcinogenesis. The aim of the present study was to determine the frequencies of important allelic variants in the N- acetyltransferase 2 (NAT2) and glutathione S- transferase (GST) genes in the Iranian population and compare them with frequencies in other ethnic populations. 2Genotyping was performed in a total of 229 unrelated healthy subjects (119 men, 110 women) for NAT2 and 170 unrelated healthy subjects (89 men, 81 women) for GST from the general Tehran population. A combination of polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) was applied for typing of NAT2 polymorphisms. Detection of GSTM1 and GSTT1 null alleles was performed simultaneously using a multiplex PCR assay. 3The frequencies of specific NAT2 alleles were 0.299, 0.314, 0.380, 0.007 and 0.000 for *4 (wild-type), *5 (C481T, M1), *6 (G590A, M2), *7 (G857A, M3) and *14 (G191A, M4), respectively. The most prevalent genotypes were NAT2 *5/*6 (29.70%) and *4/*6 (21.40%). The GSTM1 - and GSTT1 -null alleles were detected in 44.7 and 21.2% of subjects, respectively. 4We found that Iranians resemble Indians with regard to allelic frequencies of the tested variants of NAT2. The predominance of slow (49.36%) and intermediate (41.47%) acetylation status compared with wild-type rapid acetylation status (9.17%) in the study group suggests the significant prevalence of the slow acetylator (SA) phenotypes in the Iranian population. Our data confirmed that Iranians are similar to other Caucasian populations in the frequency of both GSTM1 - and GSTT1 -null alleles. [source] | |||||||||||||