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B Masquelier

Publications and source records attributed to B Masquelier.

At least 19 recordsLinked to original sources
PubMed2006

HIV-1 reverse transcriptase (RT) genotypic patterns and treatment characteristics associated with the K65R RT mutation.

BACKGROUND: The K65R HIV-1 reverse transcriptase (RT) mutation is a multidrug resistance mutation which may be correlated with specific antiretroviral combinations and with the presence or absence of other RT resistance mutations. OBJECTIVES: The aims of this study were: (i) to determine the prevalence of the K65R mutation in a cohort of antiretroviral-treated patients; (ii) to study genotypic patterns and treatment characteristics in patients in whom the K65R mutation was present. STUDY DESIGN: We included in the study all antiretroviral-experienced patients followed up at the Bordeaux University Hospital in 2003 and 2004 for whom an HIV-1 genotypic resistance analysis was available. Information on RT resistance mutations was reported from a hospital database including therapeutic and biological parameters. The prevalence of K65R was investigated for all patients. Genotypic patterns and treatment characteristics were examined at the time of detection of the K65R mutation. RESULTS: The prevalence of K65R was 1.9% (26 of 1404 patients). K65R was associated with nucleoside RT inhibitor-based regimens in 22 patients, and with tenofovir disoproxil fumarate, lamivudine, didanosine and abacavir in 23, 17, 17 and eight patients, respectively. The M184V and Q151M mutations were the most commonly co-selected substitutions. Thymidine analogue mutations (TAMs) were rarely co-selected with K65R and inversely associated with K65R. CONCLUSION: The K65R mutation may emerge preferentially in the absence of zidovudine and TAMs, suggesting the possibility of an antagonistic interaction between K65 and TAMs.

Anti-HIV Agents↗
PubMed2004

Detection of human immunodeficiency virus type 1 antiretroviral resistance mutations by high-density DNA probe arrays.

Genotypic resistance testing has become an important tool in the clinical management of patients infected with human immunodeficiency virus type 1 (HIV-1). Standard sequencing methodology and hybridization-based technology are the two principal methods used for HIV-1 genotyping. This report describes an evaluation of a new hybridization-based HIV-1 genotypic test of 99 clinical samples from patients infected mostly with HIV-1 subtype B and receiving treatment. This test combines RNA extraction with magnetic silica particles, amplification by nested reverse transcriptase PCR, and detection with high-density probe arrays designed to detect 204 antiretroviral resistance mutations simultaneously in Gag cleavage sites, protease, reverse transcriptase, integrase, and gp41. The nested reverse transcriptase PCR success rates at viral loads exceeding 1,000 copies/ml were 98% for the 2.1-kb amplicon that covers the Gag cleavage sites and the protease and reverse transcriptase genes, 92% for the gp41 amplicon, and 100% for the integrase amplicon. We analyzed 4,465 relevant codons with the HIV-1 DNA chip genotyping assay and the classic sequence-based method. Key resistance mutations in protease and reverse transcriptase were identified correctly 95 and 92% of the time, respectively. This test should be a valuable alternative to the standard sequence-based system for HIV-1 drug resistance monitoring and a useful diagnostic tool for simultaneous multiple genetic analyses.

Anti-HIV Agents↗
PubMed2004

[Viral assumption and inverted papilloma: role of human herpes viridae n 8].

INTRODUCTION: The aetiology of inverted papillomas is still not known. Current thinking favours a viral agent in particular OBJECTIVE: To widen viral research to "Human Herpes Viridae n 8" (HHV 8). MATERIAL AND METHOD: 14 patients were included in a prospective study over a 38 months period. The average age was 49.6 years. The technique used is the PCR. RESULTS: No samples revealed the presence of HHV n8. CONCLUSION: The virus "human herpes viridae" was found in no samples, but as long as the etiopathogeny of the inverted papilloma is unknown. Further viral research is needed.

Adult↗
PubMed2001

Mechanism of virologic failure after substitution of a protease inhibitor by nevirapine in patients with suppressed plasma HIV-1 RNA.

A prospective study was set up to evaluate the emergence of HIV-1 resistance after a switch from an effective protease inhibitor (PI)-containing regimen to a multitherapy regimen including nevirapine (NVP). After 6 months with an undetectable viral load under a PI-containing regimen, the patients were switched to NVP with conservation of the associated nucleoside reverse transcriptase inhibitors (NRTIs). Patients were followed-up at 1 month and then every 3 months after switching therapy. Nucleotide sequence analysis of the pol gene was performed at the first points of virologic failure. Thirty-four patients were included. The NRTI-naive group (22 patients) had begun antiretroviral therapy with a PI-containing regimen, whereas 12 patients (experienced group) had been previously treated by nucleoside mono-and/or dual therapy. After a median follow-up of 40 weeks, no patient of the naive group, versus 41% of the experienced group, developed a virologic failure after the change toward NVP ( p =.003). The virologic failures were associated with the appearance of NNRTI-resistant mutations. All rebound mutants also presented NRTI-resistance mutations. These results are consistent with a higher risk of virologic failure after a switch to an NNRTI in patients with prior suboptimal treatment and suggest the hypothesis that archived resistant viruses may facilitate the emergence of NNRTI resistance.

Anti-HIV Agents↗
PubMed2001

Prevalence of resistance mutations in antiretroviral-naive chronically HIV-infected patients in 1998: a French nationwide study.

OBJECTIVE: To estimate the prevalence of resistance-conferring mutations to antiretroviral drugs in previously untreated patients with chronic HIV-1 infection as a basis for French recommendations on viral genotyping before antiretroviral treatment initiation. DESIGN: Resistance mutations were sought in samples from 404 patients seen in 23 specialized centres throughout metropolitan France in 1998. METHODS: The protease and reverse transcriptase (RT) genes of plasma virions were sequenced. Primary and secondary protease and RT gene mutations were identified from the International AIDS Society resistance testing - USA panel. RESULTS: The prevalence of patients with primary and secondary mutations were 3.7% (95% CI 1.7-5.7) and 50.3% (95% CI 45.0-55.6), respectively. The prevalence of patients with mutations associated with resistance to nucleoside RT inhibitors (NRTI) and non-nucleoside RT inhibitors was 3.3% (95% CI 1.5-5.1) and 0.8% (95% CI 0.0-1.7), respectively. The prevalence of patients with NRTI primary mutations differed according to whether seropositivity had been diagnosed more or less than one year previously (0.2 versus 2.2% P = 0.023). Primary mutations associated with protease inhibitor resistance occurred at a prevalence of 1.9% (95% CI 0.5-3.4) with no difference according to the duration of known seropositivity. CONCLUSION: In France, in 1998, the prevalence of patients with primary mutations associated with resistance to antiretroviral drugs was low. Genotyping before the initiation of therapy was not recommended in chronically HIV-1-infected naive patients. A national sentinel survey of resistance in this clinical setting is performed regularly to update the recommendations for resistance testing.

Adult↗
PubMed2001

Clinical, biologic, and behavioral predictors of early immunologic and virologic response in HIV-infected patients initiating protease inhibitors.

Predictors of virologic (plasma HIV RNA viral load [VL] < 500 copies/ml) and immunologic (rise in CD4+ cell count > 50 cells/mm3) response after 4 months of therapy (M4) were studied in 750 HIV-1-infected patients prospectively enrolled at the initiation of a protease inhibitor (PI)-containing regimen. A virologic response was observed in 80% of patients, and an immunologic response was observed in 64%. Sixty-two percent of patients self-reported full adherence to therapy at 1 month of therapy (M1) and M4. In multivariate analysis, a virologic response was more frequent in fully adherent patients (odds ratio [OR] = 2.0; p =.001). An immunologic response was associated with age < 36 years (OR =1.4; p =.03), baseline VL (OR = 1.5 per 1 log10 copies/ml higher; p <.01), decrease in VL at M1 (OR = 1.5 per 1 log10 copies/ml decrease; p <.01), baseline total lymphocyte count (OR = 1.7 per 50% lower; p <.001), and baseline CD4+ cell percentage > or = 20% (OR =1.9; p <.001) but not with adherence to therapy. Full adherence seems to be a major predictor of a virologic response to PI-containing triple therapy. An immunologic response may be possible despite incomplete adherence, at least early in therapy.

Adult↗
PubMed2001

Zidovudine genotypic resistance in HIV-1-infected newborns in the French perinatal cohort.

A retrospective study was set up to investigate the frequency of zidovudine (ZDV)-resistant HIV-1 in infected newborns after ZDV prophylaxis in the French Perinatal Cohort study. Nucleotide sequence analysis was carried out from 34 infants' isolates and 18 maternal plasma samples. Mutations related to ZDV resistance were found in the HIV-1 reverse transcriptase in 7 of 34 children (20%). Evidence of mother-child transmission of ZDV-resistant HIV-1 was found in 4 cases. Phylogenetic analysis showed that 14 of 34 HIV-1 isolates from the infants belonged to non-B subtypes. The presence of ZDV resistance-encoding mutations in the newborn isolates was associated with a longer total duration of exposure to ZDV. In a context of a wide HIV-1 variability, ZDV resistance can be one of the factors contributing to mother-child transmission.

Anti-HIV Agents↗
PubMed2001

Genotypic and phenotypic resistance patterns of human immunodeficiency virus type 1 variants with insertions or deletions in the reverse transcriptase (RT): multicenter study of patients treated with RT inhibitors.

Genomic rearrangements in the 5' part of the human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) have been involved in multidrug resistance to nucleoside RT inhibitors (NRTI). We carried out a retrospective, multicenter study to investigate the prevalence, variability, and phenotypic consequences of such rearrangements. Data concerning the HIV-1 RT genotype and the biological and clinical characteristics of NRTI-treated patients were collected from 10 virology laboratories. Sensitivities of the different HIV-1 variants to RT inhibitors were analyzed in a single-cycle recombinant virus assay. Fifty-two of 2,152 (2.4%) RT sequences had a rearrangement in the 5' part of the RT, with an extensive molecular variation. The number of codons inserted between positions 68 and 69 ranged from 1 (3 samples) or 2 (41 samples) to 5 and 11 in one case each. In four cases, codon 67 was deleted. High levels of phenotypic resistance to zidovudine (AZT), lamivudine (3TC), stavudine (d4T), abacavir (ABC), and didanosine (ddI) were found in 95, 92, 72, 62, and 15% of the 40 samples analyzed, respectively. Resistance to AZT, d4T, and ABC could be found in the absence of the T215Y/F mutations. Resistance to 3TC could develop in the absence of specific mutations. Low-level resistance to ddI was noticed in 40% of the patients. The deletions of codon 67 seemed to have little effect on NRTI sensitivity. Most of the rearrangements were shown to contribute to cross-resistance to NRTI. The results regarding susceptibility to ddI raise the question of the interpretation of the phenotypic data concerning this drug.

Drug Resistance, Microbial↗
PubMed1999

Comparison of the immunoglobulin-G-specific seroreactivity of different recombinant antigens of the human herpesvirus 8.

The open reading frames ORF 52, ORF 65, K12, and K8.1 of the human herpesvirus 8 (HHV8) were expressed as glutathione-S-transferase (GST) fusion proteins and analysed by Western blotting (WB) and enzyme-linked immunosorbent assay (ELISA). The open reading frame (ORF) 65 and K8.1 antigens gave the highest reactivity (71%) in sera from HIV-dependent Kaposi's sarcoma (KS) patients. Therefore both antigens appear to be essential for HHV8 diagnostics, whereas ORF K12 and ORF 52 were of minor importance. Using polymerase chain reaction (PCR) out of the peripheral blood of these KS patients, 48% were detected as positive. By testing an N-terminal-deleted construct (amino acid 80-171) of ORF 65, we could show that the N-terminal region of this protein is essential to mediate full immunogenic reactivity. By analysing different deletion mutants of ORF K8.1, the major epitope was found to be located between aa 29 and 101. The prevalence of antibodies directed against the different antigens was determined for healthy blood donors to be 3-6%. The different antibody patterns obtained in HIV-patients with and without KS support the hypothesis that different antibody profiles develop during the course of KS.

Antigens, Viral↗
PubMed1999

The Spectrum of Cutaneous Lymphomas in HIV infection: a study of 21 cases.

We studied 21 HIV-associated lymphomas with cutaneous presentation to determine whether they showed features of primary cutaneous lymphoma arising fortuitously or whether they represented the cutaneous involvement of AIDS systemic lymphoma. Besides rare mycosis fungoides (n = 3), which shared typical clinicopathologic lesions, nonepidermotropic large-cell lymphomas (n = 18) were predominant. They frequently presented as a solitary nodule or tumor. Seven of the eight large T-cell lymphomas had a CD30-positive (CD30+) phenotype but did not express ALK protein. Overexpression of p53 protein was observed in six cases. Although EBV-EBER transcripts were detected in two of them, LMP1 protein was absent. Except for their original prevalence, the features of these T-cell CD30+ cutaneous lymphomas were the same as in immunocompetent patients. The 10 B-cell cutaneous lymphoma were immunoblastic or centroblastic lymphomas, with a differential expression of BCL-6 and Syndecan. Four of them expressed CD30, EBER-EBV transcripts, and LMP1 and p53 proteins. This B-cell CD30+ EBV+ phenotype contrasts with cutaneous lymphoma in immunocompetent patients. Human herpesvirus 8 was not involved in lymphomagenesis since its sequences were detected in a single patient with Kaposi's sarcoma and Castleman's disease. These lymphomas occurred in severely immunocompromised patients with a low CD4 count. Death was due to immunodepression rather than to lymphoma spread, suggesting avoiding aggressive immunosuppressive treatment in such patients.

Adult↗
PubMed1999

Zidovudine resensitization and dual HIV-1 resistance to zidovudine and lamivudine in the delta lamivudine roll-over study.

OBJECTIVE: To study zidovudine resensitization and dual resistance to zidovudine/lamivudine in HIV-1 isolates from nucleoside reverse transcriptase (RT) inhibitor-experienced patients during selective pressure exerted by zidovudine/lamivudine combination therapy. DESIGN AND METHODS: HIV-1 isolates from 29 patients receiving zidovudine/lamivudine combination therapy in the Delta roll-over study were analysed at entry and during a 1 year follow-up period for phenotypic susceptibility to zidovudine and lamivudine in the ANRS PBMC assay. The RT gene from codon 20 to 230 and at codon 333 was analysed by nucleotide sequencing of the corresponding isolates. RESULTS: HIV-1 isolates from 23 of the 29 patients were phenotypically resistant to zidovudine at baseline; 61% of these patients showed significant zidovudine resensitization during follow-up. The zidovudine IC50 value correlated positively with log10 plasma HIV-1 RNA (P = 0.02) and negatively with the CD4 cell count (P = 0.004). Zidovudine resensitization (related to acquisition of the M184V mutation) was transient, with evolution towards dual resistance to zidovudine and lamivudine in 20 of the 29 patients. The phenotype of certain dually resistant isolates coincided with the emergence of multiple mutations in the 5' part of the RT gene. CONCLUSIONS: M184V-mediated zidovudine resensitization of HIV-1 is transient in most patients who are given zidovudine/lamivudine combination therapy when zidovudine resistance has already emerged. The subsequent evolution towards dual phenotypic resistance to zidovudine/lamivudine corresponds to complex genotypic profiles.

Anti-HIV Agents↗
PubMed1996

Kinetics of appearance of neutralizing antibodies in 12 patients with primary or recent HIV-1 infection and relationship with plasma and cellular viral loads.

HIV-1 primary infection is characterized by a short high titer viremia, which rapidly declines as the immune response emerges. The role of autologous neutralizing antibodies in the decline of viral replication was evaluated in 12 patients with primary or recent HIV-1 infection. Neutralizing antibodies detected for each patient could not generally be observed before several months after isolation of the first obtained HIV isolate. The plasma viral load, as measured by quantitation of the HIV-1 RNA, underwent a global decrease during the first 6 months of the infection, but this decrease did not seem to be associated with the emergence of neutralizing antibodies. The proviral load in peripheral blood mononuclear cells, which was studied by quantitative DNA polymerase chain reaction, exhibited fluctuations and was not as well curtailed as the plasma viremia in the majority of patients.

Adult↗
PubMed1996

Neonatal characteristics in rapidly progressive perinatally acquired HIV-1 disease. The French Pediatric HIV Infection Study Group.

OBJECTIVE: To identify clinical and laboratory parameters at birth that are associated with the rapidly progressive form of human immunodeficiency virus type 1 (HIV-1) disease in children born to infected mothers. DESIGN: Multicenter, prospective study of infants born to HIV-seropositive mothers. SETTING: A total of 62 obstetric and pediatric centers in France. PARTICIPANTS: Of 1386 children born to HIV-1-seropositive mothers at least 18 months before the cutoff date, 267 were infected. Infection was defined as serological positivity at 18 months or death from HIV disease before the age. MAIN OUTCOME MEASURE: Category C events (including opportunistic infections, recurrent severe bacterial infections, cancers, specific encephalopathy, and wasting syndrome) in the new pediatric Centers for Disease Control and Prevention classification during the first year of life, according to clinical, immunological, and virological findings at birth. RESULTS: The risk of category C manifestations at 12 months was significantly higher when an infected newborn had liver and/or spleen enlargement and/or adenopathies (38.1% vs 15.1%; relative risk [RR], 2.5; 95% confidence interval [CI], 1.4 to 6.0; P<.02) or a low proportion (<30%) of CD4+ cells at birth (45.5% vs 15.0%; RR, 3.0; 95% CI, 1.4 to 6.4; P<.005). Similarly, HIV-1 culture and/or polymerase chain reaction positivity during the first week of life was associated with a higher risk of the early, severe form of HIV infection (26.4% vs 9.3%; RR, 2.8; 95% CI, 1.3 to 6.1; P<.006). In case of positive antigenemia at birth, the risk was 50.0% vs 14.4% (RR, 3.5; 95% CI, 1.9 to 6.2; P<.001). These parameters, determined at birth, were strongly interrelated and could reflect active disease onset in utero in some cases of early, severe HIV-1 disease in childhood. CONCLUSIONS: These prognostic markers, particularly virological parameters, are of value in monitoring children infected by HIV and might serve as a basis for early therapeutic intervention.

AIDS Serodiagnosis↗
PubMed1996

Multicenter evaluating of a commercially available PCR assay for diagnosing enterovirus infection in a panel of cerebrospinal fluid specimens.

Thirteen laboratories participated in blind tests of a panel of 20 coded cerebrospinal fluid specimens (7 uninfected samples, 3 samples infected with 1 50% tissue culture infective dose [TCID50]/0.1 ml [nonenterovirus strains], and 10 samples infected with 10, 1, or 0.1 TCID50/0.1 ml [three different enterovirus serotypes]) on the Amplicor enterovirus PCR assay (Roche Diagnostic Systems). The panel was also evaluated by in-house PCR (two nested-PCR and three one-step PCR assay) or tissue culture (eight laboratories). The viral load was shown to influence greatly the sensitivity of the assay. The average sensitivity of the Amplicor test ranged from 67 to 98% for viral titers of 1 to 10 TCID50/0.1 ml, respectively; titers of 0.1 TCID50/0.1 ml resulted in a sensitivity of only 16%. The overall specificity of the Amplicor test was 98%. The Amplicor assay compared favorably to the five in-house PCR tests (no significant difference in either sensitivity or specificity) and was much more sensitive than tissue culture (P < 0.001), even for high viral loads. It was easy to perform, rapid (about 6 h), well-standardized, and appeared to be suitable for the diagnosis of enterovirus meningitis on a routine basis in laboratories trained in molecular biology techniques.

Base Sequence↗