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V Calvez

Publications and source records attributed to V Calvez.

At least 73 records · Page 4Linked to original sources
PubMed1999

[Polymorphism of protease genes in patients infected with HIV-1 and response to therapy including a protease inhibitor].

Protease inhibitors (PIs) are recently introduced drugs that have improved the survival of HIV-infected patients when given in combination with two reverse transcriptase inhibitors. The HIV-1 protease gene is naturally highly polymorphic. Selection pressure due to IP use can result in major or minor resistance-associated mutations (RAMs). This study investigated whether presence before IP therapy of minor RAMs on the protease gene predicts the virological response. Of the 58 PI-naive patients included in the study, 12 had received two nucleoside reverse transcriptor inhibitors, 14 had received indinavir, 16 ritonavir, and 28 saquinavir-SGC. Viral load was measured on D0 (prior to PI initiation) and at M3 and M6 (Roche Monitor 1.5 with 200 and 20 copies/ml as the thresholds). The protease gene was fully sequenced on D0 using the ABI 377 automatic sequencer after RNA amplification by nested RT-PCR. None of the viral strains exhibited major mutations, but 57 of 58 (98%) had at least one minor mutation (median number of substitutions, 4), 60% had 1 to 4 substitutions, and 40% had 5 to 9 substitutions. Substitutions seen with a prevalence > 20% were located at codons 15, 35, 37, 41, 63, and 77. Numbers of substitutions at M3 and M6 were not correlated with viral load or the nature of the PI used, and neither were they significantly different between patients with more or fewer than 20 copies/ml. These data suggest that the protease genotype at PI initiation does not predict the efficacy of a regimen including a PI and is of no assistance in deciding whether or not to include a PI in a triple combination regimen.

Acquired Immunodeficiency Syndrome↗
PubMed1999

Stavudine resistance: an update on susceptibility following prolonged therapy.

The current report summarizes the available published and unpublished data from several investigators on resistance in clinical isolates following prolonged stavudine therapy. Results suggest that stavudine resistance is both modest in degree and infrequent in appearance. Phenotypic evaluation of 61 patients on stavudine therapy showed only modest changes in drug sensitivity following up to 29 months of treatment. The post-treatment isolates from 15 patients exhibited an increase in EC50 value > fourfold (level above variability of assay) when compared with the corresponding pretreatment isolates. However, the vast majority (11) of these pretreatment isolates either had unexpectedly low EC50 levels and/or had post-treatment isolates that lacked any amino acid changes within their reverse transcriptase (RT) gene to account for the observed change in sensitivity. Of the four remaining isolates, two appeared to have a multi-resistant phenotype to several nucleoside analogues and two had no detectable RT amino acid changes to account for the observed change in stavudine sensitivity. To date, clinical HIV-1 isolates displaying stavudine-specific resistance have yet to be reported. Furthermore, full or partial RT sequence analysis of 194 post-treatment isolates failed to identify any consistent amino acid changes. The strain-specific V75T mutation reported to confer stavudine resistance to the HXB2 HIV-1 strain in vitro, was found in only six isolates and did not correlate with stavudine resistance. This low incidence of stavudine resistance is in striking contrast to that observed with other nucleoside analogues and further supports the use of stavudine in first-line combination therapy for HIV patients.

Acquired Immunodeficiency Syndrome↗
PubMed1999

[Antiretroviral therapy and immune reconstitution].

The course of the HIV infection has been dramatically modified since the introduction of highly active antiretroviral therapy (HAART) combining inhibitors of the HIV-1 reverse transcriptase and protease. Despite some controversies about the extent to which the immune system can normalize, it is generally admitted nowadays that a numerical and functional CD4 cell profile more akin to asymptomatic HIV-infected individuals can be restored in AIDS patients and can confer host protection against opportunistic events. The best hallmark of such immune restoration is the massive decline in the mortality and morbidity related to AIDS that have been registered in all industrialized countries. These changes involve a recirculation of mature peripheral T cells, a regeneration of naive T cells from thymic origin and a restoration of memory CD4 T cell réactivities. Although these recent advances warrant increased optimism, HAART by reducing the virus burden is unable to restore immunity against HIV itself, except when introduced at the very early stage after virus inoculation. The single condition required for immune reconstitution is an efficient and durable inhibition of virus replication. These positive effects can be obtained at late stages of the disease even when the patients have been heavily pre-treated. They also demonstrate that HIV does not definitively alter the lymphoid tissues nor the immune defenses, even aller years of infection and severe immune suppression, except for HIV-specific CD4 T helper cells.

CD4 Lymphocyte Count↗
PubMed1998

Efficacy and tolerability of stavudine plus lamivudine in treatment-naive and treatment-experienced patients with HIV-1 infection.

BACKGROUND: A combination of two nucleoside analogues is currently the core of any antiretroviral regimen for HIV-1 infection. Stavudine plus lamivudine has shown an additive effect in vitro, as well as an absence of overlapping toxicity and cross-resistance. OBJECTIVE: To evaluate the antiviral efficacy of stavudine plus lamivudine in treatment-naive patients and in patients previously treated with other nucleoside reverse transcriptase inhibitors. DESIGN: Prospective, open-label pilot study. SETTING: Three urban clinical centers in Paris. PATIENTS: 83 patients with CD4+ cell counts between 50 and 400 cells/mm3 (42 treatment-naive and 41 treatment-experienced patients). INTERVENTIONS: Stavudine, 40 mg twice daily (30 mg twice daily in patients with a body weight < or = 60 kg), and lamivudine, 150 mg twice daily. MEASUREMENTS: Primary end points for efficacy included changes in plasma viral load and CD4+ cell count at 24 weeks compared with baseline. RESULTS: Therapy with stavudine plus lamivudine resulted in a median decrease of 1.66 log10 (10(1.66)) (range, -3.04 to -0.79 log10) in plasma HIV-1 RNA; the median increase in CD4+ cell count was 108 cells/mm3 (range, -58 to 406 cells/mm3) at week 24 in treatment-naive patients. In treatment-experienced patients, the median reduction in plasma HIV-1 RNA was 0.55 log10 (range, -2.86 to 0.52 log10), and the median increase in CD4+ cell count was 46 cells/mm3 (range, -188 to 311 cells/mm3). The percentages of patients with less than 3000 HIV-1 RNA copies/mL and less than 400 copies/mL at 24 weeks were, respectively, 57% (95% CI, 41% to 72%) and 26% (CI, 12% to 40%) among treatment-naive patients and 22% (CI, 10% to 38%) and 5% (CI, 1% to 17%) among treatment-experienced patients. Of 82 patients, 14 (17%) experienced grade 3 or 4 toxicity and 2 discontinued therapy because of intolerance toward treatment. CONCLUSION: Stavudine plus lamivudine seems to have a potent antiviral effect in treatment-naive and treatment-experienced patients. No major drug-limiting toxicity was found. This two-nucleoside combination should be considered in multidrug therapy for HIV.

Adult↗
PubMed1998

Long-lasting recovery in CD4 T-cell function and viral-load reduction after highly active antiretroviral therapy in advanced HIV-1 disease.

BACKGROUND: Highly active antiretroviral therapy (HAART) decreases viral load and increases CD4 T-cell counts in patients with advanced HIV-1 infection. Whether HAART can improve CD4 T-cell function, and the biological characteristics affecting immune reconstitution, remain unclear. We undertook an open prospective pilot study to address these issues. Both treatment-naïve and previously treated patients were included. METHODS: 20 patients (seven naïve, 13 previously treated) were treated with one protease inhibitor and two reverse-transcriptase inhibitors and followed up for 12 months. We measured CD4-cell proliferation in response to cytomegalovirus and tuberculin antigens and counted subsets of CD4 cells at baseline and months 1, 3, 6, 9, and 12. Patients who had no antigen-specific reactivity at baseline but developed it while receiving HAART were classified as immunological responders. FINDINGS: Four patients had antigen-specific reactivity at baseline compared with 14 at month 12 (p <0.001). Between month 3 and month 12 viral load fell by a median of 1.5 log copies/mL from baseline (4.6 log copies/mL) and CD4-cell count increased by a median of 63/microL (from 93/microL). Ten patients (six of seven naïve, four of 13 previously treated) were immunological responders. They differed significantly from the ten non-responders in that their viral-load reduction was sustained for 12 months, the increase in CD4 count was greater, and they showed an early increase in memory CD4 T cells with an increase of naïve T cells. INTERPRETATION: HAART can induce sustained recovery of CD4 T-cell reactivity against opportunistic pathogens in severely immunosuppressed patients. This recovery depends not on baseline values but on the amplitude and duration of viral-load reduction and the increase of memory CD4 T cells.

Adult↗
PubMed1998

Susceptibility of peripheral blood mononuclear cells to apoptosis is correlated to plasma HIV load.

OBJECTIVES: To quantify spontaneous and activation-induced apoptosis in peripheral blood mononuclear cells (PBMC) of HIV-infected patients and to look for correlations between PBMC apoptosis levels, stages of HIV disease, CD4 count, and plasma viral load. STUDY POPULATIONS: 75 consecutive inpatients and outpatients infected with HIV (mean CD4 count, 202 +/- 182 x 10(6)/L; mean plasma viral load, 4 +/- 1.29 log10 RNA copies/ml) and a control group composed of 18 healthy, HIV-negative adults. METHODS: Spontaneous apoptosis was detected at the single-cell level by direct incorporation of fluorescein-deoxyuridine triphosphate (dUTP) in PBMC DNA strand breaks. Activation-induced apoptosis was determined after in vitro stimulation with anti-CD3 antibodies and interleukin-2 (IL-2). RESULTS: Spontaneous apoptosis was low in patients and controls, whereas activation-induced apoptosis was significantly higher in HIV-infected patients (5.22 +/- 4.32% versus 2.46 +/- 1.77%, respectively; p = .009). The degree of activation-induced apoptosis was positively correlated with the plasma viral load (r = 0.29; p = .029) and negatively correlated with the CD4 count (r = -0.37; p = .0009). Although activation-induced apoptosis was significantly higher in patients fulfilling AIDS criteria, it did not differ significantly between patients with an acute AIDS-defining event and those with stable disease. CONCLUSION: Susceptibility of PBMC to apoptosis in HIV-1-infected patients is correlated to the plasma viral load and the stage of the disease.

Adult↗
PubMed1998

Prevalence of human herpesvirus 8 infection measured by antibodies to a latent nuclear antigen in patients with various dermatologic diseases.

BACKGROUND: Human herpesvirus 8 (HHV-8) has been detected in all epidemiological forms of Kaposi sarcoma (KS). The role of HHV-8 in dermatologic diseases other than KS is controversial. Some studies based on polymerase chain reaction findings suggest an association between HHV-8 and epithelial tumors of the skin, lymphoproliferative disorders, or pemphigus. OBJECTIVE: To assess the prevalence of antibodies against a latent nuclear antigen of HHV-8 in patients with various dermatologic diseases. DESIGN: An indirect immunofluorescence assay was used to search for HHV-8 antibodies. SETTING: Ambulatory or hospitalized patients from a university hospital associated with a research laboratory. PATIENTS: Eighty-three patients with various non-KS dermatologic diseases and 16 patients with KS who were seronegative for the human immunodeficiency virus. Controls were 100 healthy subjects living in the same area. RESULTS: Antibodies to HHV-8 were found in 100% (16/16) of the patients with KS and 3.6% (3/83) of the patients with non-KS dermatologic diseases: 1 patient with pemphigus vulgaris, 1 with discoid lupus erythematosus, and 1 with bullous pemphigoid. The prevalence of antibodies to HHV-8 in controls was 2% (2/100) and was not significantly different than the prevalence in patients with dermatologic diseases other than KS (P =.28). CONCLUSIONS: Our serologic study confirms the higher prevalence of HHV-8 antibodies in patients with KS and demonstrates that contrary to other human herpesviruses, HHV-8 is not a ubiquitous virus in France. We could not determine any causal association between HHV-8 and pemphigus or lymphoproliferative disorders of the skin.

Adult↗
PubMed1998

The level of human immunodeficiency virus (HIV) type 1 RNA in cerebrospinal fluid as a marker of HIV encephalitis.

We prospectively evaluated the level of human immunodeficiency virus (HIV) type 1 RNA in cerebrospinal fluid (CSF) as a marker of HIV encephalitis. Fifty-two HIV-1-infected patients (41 males and 11 females; mean age, 39 years) were tested for the presence of HIV-1 RNA in plasma and CSF. Samples of CSF were obtained by lumbar puncture to evaluate cognitive deficits, seizures, or fever among these patients. HIV encephalitis was diagnosed in 11 patients (21%), other CNS diseases were diagnosed in 12 (23%), and fever without CNS disease was diagnosed in 29 (56%). HIV-1 RNA was detectable in 92% of the plasma specimens and 75% of the CSF specimens. No significant difference was observed in CSF levels of HIV-1 RNA between patients with or without HIV encephalitis. CSF levels of HIV-1 RNA correlated with plasma levels of HIV-1 RNA (Spearman's rank correlation, +0.31; P = .02) and CSF white blood cell counts (Spearman's rank correlation, +0.4; P < .01). The absence of any significant difference between patients with or without HIV encephalitis suggests that the CSF HIV-1 RNA level is not a good marker for the diagnosis of HIV encephalitis.

AIDS Dementia Complex↗
PubMed1998

CD8hi+CD57+ T lymphocytes are enriched in antigen-specific T cells capable of down-modulating cytotoxic activity.

Major expansions of CD8hi+CD57+ T lymphocytes frequently occur during human immunodeficiency virus (HIV) infection and after transplantation. To investigate mechanisms of such cell expansion, we compared the activation and functional status of CD8hi+CD57+ and CD57-peripheral blood lymphocytes (PBL) from normal, bone marrow transplantation (BMT) and HIV+ donors. The CD8hi+CD57+ PBL from BMT and HIV+ donors preferentially displayed CD38 and HLA-DR activation markers without correlation between CD8hi+CD57+ percentages and HIV load, the CD45RA+ isoform in all ex vivo conditions but acquired CD45RO after in vitro expansion, CD11b and CD11c in BMT and HIV+ donors but decreased expression of CD62-L, VLA-2 and VLA-6. The CD8hi+CD57+ cells were positive for perforin and granzyme B and spontaneously mediated cytolytic activity in a CD3-redirected assay. In contrast the inhibitor of cytolytic functions (ICF) produced by CD8hi+CD57+ cells down-modulated the CD3-redirected cytolytic activity but only at low levels of CD3 cross-linking. While CD3-triggering induced a low, if any, short-term proliferation of CD8+CD57+ cells, this subset could be amplified after long-term stimulation either with mitogens or with HIV antigens, thereby enriched in HIV-specific T cells producing tumor necrosis factor-alpha. Altogether these data suggest that CD8hi+CD57+ cells represent a terminal differentiation state of activated effector cytotoxic T lymphocytes which are enriched in antigen-specific T cells and down-modulate their own cytolytic potential, thus participating in a negative control of effector cell functions during persistent viral infections or transplantations.

CD57 Antigens↗
PubMed1998

Line probe assay for detection of human immunodeficiency virus type 1 mutations conferring resistance to nucleoside inhibitors of reverse transcriptase: comparison with sequence analysis.

We compared the line probe assay (LiPA) to sequence analysis for the detection of mutations conferring resistance to nucleoside inhibitors of human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT). Plasma samples from 40 patients who had received zidovudine, dideoxyinosine, and dideoxycytosine, alone or in combination, and who were enrolled in the ALTIS 2 clinical trial (lamivudine [3TC] plus stavudine) were tested at enrollment and at week 24. RT PCR products from plasma were used for LiPA, and DNA was used for sequence analysis. LiPA gave uninterpretable results for 8.5% of the analyzed codons corresponding to 63 samples, mainly for codons 41, 69, and 70. Several minor discrepancies between the two methods occurred, mainly due to the ability of LiPA to detect mixed populations while sequence analyses detect a single homogeneous population. LiPA is suitable for detecting mixed populations and easy to implement in clinical laboratories and might be useful for epidemiological surveys of primary HIV-1 resistance.

Anti-HIV Agents↗
PubMed1998

Resistance to antiretroviral drugs.

There are many questions regarding testing for viral resistance to antiretroviral drugs and interpretation of test results. The most appropriate time for testing and the compartment from which to derive virus are still uncertain. Both phenotypic and genotypic tests are used to measure drug susceptibility; however, interpretation of results of these assessments is not clear-cut. Furthermore, correlation of these test results with clinical outcome or pharmacological data is limited by lack of studies and other confounding factors.

Anti-HIV Agents↗
PubMed1998

[Clinical importance of the quantification of HIV-1 RNA in cerebrospinal fluid for the diagnosis of HIV encephalitis].

We evaluated prospectively the HIV-1 RNA level in CSF as a marker of HIV encephalitis diagnosis. 110 HIV-1 infected patients (mean age: 39 years; sex-ratio M/F: 94/16) were tested for HIV-1 RNA in plasma and CSF. Lumbar punctures were performed to explore cognitive deficit, seizure or fever. HIV encephalitis was diagnosed in 15 patients (14%), other CNS disease in 34 (31%), and fever without CNS disease in 61 (55%). HIV-1 RNA was detectable in 93% of the plasma and in 62% of the CSF. No significant difference was observed in CSF HIV-1 RNA between patients with or without HIV encephalitis. CSF HIV-1 RNA was correlated with plasma HIV-1 RNA (p < 0.01), CSF protein (p < 0.01) and CSF white cell counts (p < 0.01). The absence of any significant difference between patients with or without HIV encephalitis, suggests that the CSF HIV-1 RNA level is not a good marker for its diagnosis.

AIDS Dementia Complex↗
PubMed1998

[HHV-8 related diseases].

KAPOSI'S DISEASE: HHV-8 sequences have been found in all the epidemiological forms of Kaposi's disease. There is a direct relationship between HHV-8 infection and PBMC and later development of Kaposi's disease. The HHV-8 sequences can be found in spindle cells or endothelial cells in Kaposi lesions. OTHER DISEASES: HHV-8 is also associated with certain lymphomas including body-cavity-based lymphomas and Castleman's disease. It has also been put forward that there is a relationship between HHV-8 and multiple myeloma, epithelial tumors in kidney transplant recipients, angiosarcoma, and angiolymphoid hyperplasia.

Herpesvirus 8, Human↗