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Line Probe (line + probe)
Selected AbstractsHuman immunodeficiency virus type 1 and hepatitis C virus Co-infection and viral subtypes at an HIV testing center in BrazilJOURNAL OF MEDICAL VIROLOGY, Issue 6 2006G.A.S. Pereira Abstract Human immunodeficiency virus (HIV) testing sites have been recognized recently as potential settings for hepatitis C virus (HCV) screening since both viruses share common routes of transmission. HIV and HCV prevalence, predictors, co-infection rates, and viral subtypes were studied in 592 attendants at an anonymous HIV Counseling and Testing Center in central Brazil. Anti-HIV-1 and -HCV antibodies were screened by ELISA, and Western blots were used to confirm HIV infection. Among HIV-seropositive samples, reverse transcriptase-polymerase chain reaction (RT-PCR) and nested-PCR were used to subtype HIV-1 by the Heteroduplex Mobility Analysis (HMA) and HCV by the line probe assay (INNO-LiPA). HIV and HCV seroprevalence was 3.2% (95% CI 2.0,4.9) and 2.5% (95% CI 1.5,4.0), respectively. Intravenous drug use was the risk factor most strongly associated with both HIV and HCV infections, even in a population with few intravenous drug users (n,=,6); incarceration was also associated with HCV. HIV/AIDS-positive sexual partner and homosexual/bisexual behaviors were associated independently with HIV-1. The prevalence of HCV infection among HIV-positive persons was 42% (95% CI 20,66), higher than in HIV-negative persons (1.2%; 95% CI 0.5,2.5). HIV-1 subtype B was identified in the env and gag regions of the genome. HCV subtype 3a predominated among co-infected persons and one HCV subtype 1a was detected. Overall, a similar prevalence of HIV and HCV infections and a higher prevalence of HCV among HIV-positive persons were observed. Integrated HIV and HCV screening at HIV testing sites may represent a unique opportunity to provide diagnosis and prevention strategies at a single visit. J. Med. Virol. 78:719,723, 2006. © 2006 Wiley-Liss, Inc. [source] Introduction of HIV type 1 non-B subtypes into Eastern Andalusia through immigrationJOURNAL OF MEDICAL VIROLOGY, Issue 1 2003Marta Alvarez Abstract A study of the distribution of HIV-1 subtypes in the native and immigrant populations of Eastern Andalusia (Southern Spain) was conducted to determine any changes between 1983 and 2001 and to identify antiretroviral resistance mutations in non-B subtype strains among the immigrant population. The study included 111 native patients from Eastern Andalusia: 94 infected with HIV before 1996 and 17 infected since 1996. A parallel study was conducted on 26 HIV-positive immigrants from Africa. Subtyping was done with the heteroduplex mobility assay. Resistance mutations were determined by line probe assay. A total of 137 patients were studied: 9.2% had subtype A (n,=,12), 80.8% subtype B (n,=,105), and 1.5% subtype C (n,=,2). Among the Eastern Andalusia population infected before 1996, 10.9% had non-B subtypes, compared with 23.5% of those infected after that year. The greatest percentage of non-B subtypes (52.4%) was found among the immigrant population. Resistance mutation K70R was detected in one of the six immigrants with non-B subtype and M41L in another. There has been a slight increase in the diversity of HIV-1 subtypes in Eastern Andalusia over the past few years, possibly influenced by non-B subtypes introduced by immigrants from sub-Saharan Africa. J. Med. Virol. 70: 10,13, 2003. © 2003 Wiley-Liss, Inc. [source] Hepatitis B virus genotypes and HBsAg subtypes in refugees and injection drug users in the United States determined by LiPA and monoclonal EIAJOURNAL OF MEDICAL VIROLOGY, Issue 3 2001Paul D. Swenson Abstract Hepatitis B virus (HBV) genotyping and hepatitis B surface antigen (HBsAg) subtyping were carried out on sera from 196 HBsAg-positive patients, including 151 refugees entering the United States and 45 injection drug users in Seattle. HBsAg subtyping was performed by enzyme immunoassay (EIA) using a panel of monoclonal antibodies and the HBV genotype was determined by polymerase chain reaction (PCR) followed by detection of amplified HBV DNA by a reverse-phase hybridization line probe assay (LiPA) using genotype-specific probes. HBV DNA was detected by PCR in 155 (79%) of the 196 sera and all 155 were genotyped by LiPA. Samples from Southeast Asia were predominantly genotype B/subtype ayw1 and genotype C/adr; samples from the former Soviet Union and eastern Europe were mostly genotype D/ayw2 and genotype D/ayw3; samples from east Africa were mainly genotype A/adw2 and genotype D/ayw2; and samples from injection drug users were mostly genotype D/ayw3 and genotype A/adw2. Some strains of ayw3 gave atypical monoclonal antibody reactivity patterns in the subtyping assay due to a Val/Ala instead of a Thr at amino acid residue 118 and a Thr instead of a Met at residue 125. A strain of ayw2 also gave an atypical monoclonal antibody reactivity pattern due to an Ala instead of a Thr at amino acid residue 123. LiPA genotyping and monoclonal EIA subtyping can provide useful information for epidemiological studies. J. Med. Virol. 64:305,311, 2001. © 2001 Wiley-Liss, Inc. [source] Performance of sequence analysis, INNO-LiPA line probe assays and AFFIGENE assays in the detection of hepatitis B virus polymerase and precore/core promoter mutationsJOURNAL OF VIRAL HEPATITIS, Issue 6 2006A. Olivero Summary., In this study, we compare results obtained by sequences analysis and commercial kits in the detection of hepatitis B virus (HBV) polymerase and precore (PC) and core promoter mutations. A total of 23 serum samples from lamivudine treated patients were tested for polymerase mutations by direct sequencing, INNO-LiPA HBV DR and AFFIGENE HBV DE/3TC. Full concordance among the three assays was observed in 63% of the total analysed codons. Concordant results were obtained between sequencing and LiPA in 80%, between sequencing and AFFIGENE in 73% and between LiPA and AFFIGENE in 74% of all tested codons. All discrepancies were observed in mixed population samples in which AFFIGENE and LiPA detected additional viral variants not revealed by sequence. In two patients, with serial samples, LiPA detected earlier than sequence and AFFIGENE an emerging mutate strain. PC and core promoter viral variants were detected in 28 serum samples collected from 14 HBV inactive carriers and from 14 hepatitis B patients with chronic liver disease. Direct sequencing, INNO-LiPA HBV PreCore and AFFIGENE HBV MUTANT VL 19 showed fully coincident results in 88% of tested positions. These findings showed that all assays evaluated were sensitive and accurate tools to analyse HBV genomic variability. Sequence analysis is essential to study new emerging mutations as LiPA and AFFIGENE assays are more easily useful in clinical laboratories to detect the appearance of well-characterized HBV variants. [source] Molecular identification and characterization of rifampicin-resistant Mycobacterium tuberculosis isolates by line probe assay: an approach for rapid diagnosis of multidrug-resistant tuberculosisLETTERS IN APPLIED MICROBIOLOGY, Issue 3 2008C. Bicmen Abstract Aim:, Early identification and characterization of rifampicin-resistant (Rr) Mycobacterium tuberculosis isolates recovered from the samples of tuberculosis (TB) patients in the Aegean (West Anatolian) Region was intended. Methods and Results:, Sixty isolates [47 (78·3%) multidrug-resistant (MDR)], which were identified as M. tuberculosis complex and phenotypically resistant to rifampicin by both BACTEC mycobacteria growth indicator tube (MGIT) 960 and 460 systems were analysed by a commercial line probe assay (INNO-LiPA Rif TB). The concordance of LiPA with the in vitro susceptibility test was found as 98·3%. Among the isolates, S531L (R5 pattern; 46·7%) and L511P/R, S512T, Q513L/K (,S1 pattern; 11·7%) were the most frequent mutation patterns. As compared with the BACTEC systems and conventional techniques for cultivation, identification and in vitro susceptibility testing, INNO-LiPA Rif TB after cultivation in BACTEC MGIT 960 system provided an average of 20 days early diagnosis of RrM. tuberculosis isolates. Conclusions:, Rapid molecular identification and characterization of RrM. tuberculosis isolates after BACTEC MGIT 960 cultivation would be useful for faster diagnosis, infection control and planning of accurate treatment in MDR-TB patients. Significance and Impact of the Study:, Patients with MDR-TB need a specified treatment and efficient follow-up strategies. Rapid and practical methodologies to diagnose and follow these patients should be applied in routine use. [source] Human papillomavirus-associated increase in p16INK4A expression in penile lichen sclerosus and squamous cell carcinomaBRITISH JOURNAL OF DERMATOLOGY, Issue 2 2008D.M. Prowse Summary Background, Human papillomaviruses (HPVs) are sexually transmitted human carcinogens that may play a role in the oncogenesis of penile cancer. Objectives, To investigate the role of HPV infection and expression of the tumour suppressor protein p16INK4A in the pathogenesis of penile cancer. Methods, By means of polymerase chain reaction amplification and reverse hybridization line probe assay to detect HPV infection, and immunohistochemical staining for p16INK4A and Ki67, we analysed 26 penile squamous cell carcinomas (SCCs) and 20 independent penile lichen sclerosus (LS) lesions from 46 patients. Results, HPV DNA was found in 54% of penile SCCs and 33% of penile LS cases in single and multiple infections. High-risk HPV 16 was the predominant HPV type detected. No relationship between Ki67 expression and HPV infection was observed. Strong immunostaining for p16INK4A correlated with HPV 16/18 infection in both penile LS and penile SCC. In our penile SCC series the cancer margins were also associated with penile LS in 13 of 26 lesions, and HPV was detected in seven of the 13 SCC cases associated with LS and in six of the 11 SCC lesions not involving LS. Conclusions, Our study shows a high prevalence of HPV 16 and p16INK4A expression in penile lesions, consistent with an active role for HPV in interfering with the retinoblastoma pathway. High-risk HPV infection could be involved in the tumorigenic process in 50% of penile cancers, and the use of prophylactic HPV vaccines has the potential to prevent these cancers. [source] Pyrazinamide resistance in multidrug-resistant Mycobacterium tuberculosis isolates in JapanCLINICAL MICROBIOLOGY AND INFECTION, Issue 8 2010H. Ando Clin Microbiol Infect 2010; 16: 1164,1168 Abstract Thirty-six multidrug-resistant (MDR) Mycobacterium tuberculosis isolates collected in Japan were examined for pyrazinamide susceptibility and pyrazinamidase activity, and analysed by pncA sequencing and a hybridization-based line probe assay (LiPA), which was used to detect pncA mutations for the rapid identification of pyrazinamide-resistant isolates. Pyrazinamide resistance was found in 19 (53%) of them. All pyrazinamide-resistant isolates had no pyrazinamidase activity and at least one mutation in pncA. Among the pncA mutations, 11 had not been previously reported. The results of the LiPA were fully consistent with the DNA sequencing results. A majority of MDR M. tuberculosis isolates in Japan were resistant to pyrazinamide. [source] | |||||||||||||