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Determines the survival improvement of children with AIDS severe pneumocystis carinii pneumonia (PCP) when administered with corticosteroids in addition to antimicrobials. Death of children treated with antimicrobials; Survival of children in corticosteroid therapy; Selection procedures; Measurements and results.

Abstract: Background: Substance use by youth living with HIV (YLWH) is a concern, given potential interactions with virus-associated immune suppression and adverse effects on risk behaviors, neurocognition, and adherence. Self-report substance use measures provide efficient cost-effective assessments. Analyses describe self-reported substance use among YLWH and examine agreement with toxicology assays. Methods: Seventy-eight youth age 18–24 years (87% male, 71% African–American) with behaviorally acquired HIV-1 infection and 55 uninfected youth completed the Alcohol, Smoking, and Substance Involvement Screening Test to assess drug use frequency, including tobacco, marijuana, cocaine, and alcohol, over the prior three months. Elisa-based toxicology assays were used to detect 27 substances in plasma. Chi-square tests compared substance use between YLWH and uninfected youth; Kappa statistics compared agreement between self-report and toxicology. Results: YLWH reported marijuana (49%), tobacco (56%), and alcohol (87%) use, with 20%, 28% and 3% reporting daily use of each substance, respectively; other substance use was uncommon. Uninfected youth reported less tobacco use but otherwise similar substance use. All youth who reported daily use of marijuana or tobacco had positive plasma toxicology results, while concordance decreased with less frequent self-reported use. Among youth reporting no substance use, few tested positive (4% YLWH, 2% uninfected youth for cannabis; 8%YLWH for tobacco). Conclusions: Youth report high rates of marijuana, tobacco, and alcohol use. Concordance between self-report and toxicology for marijuana and tobacco use, particularly for daily users, supports self-report as a valid indicator of substance use in research studies of youth with or without HIV-1 infection. [Copyright &y& Elsevier]

Abstract: Intravenous immunoglobulin (IVIg) is used in treating immunodeficiencies and autoimmune or inflammatory disorders. As manufacturing processes and storage can alter IgG molecules, pharmacokinetic assessments are important for new preparations. Thus, we studied pharmacokinetics of IgPro10, a new 10% liquid IVIg product stabilised with l-proline, in patients with common variable immunodeficiency (CVID) and X-linked agammaglobulinaemia (XLA). Patients received IgPro10 for ≥4 months (median dose of 444mg/kg, at 3- or 4-week intervals). Median total IgG serum concentrations increased from 10.2g/l pre-infusion to 23.2g/l at infusion end. Serum IgG concentrations decreased in a biphasic manner; median terminal half-life was 36.6 days. Median half-lives were 33.2 for IgG1, 36.3 for IgG2, 25.9 for IgG3 and 36.4 days for IgG4. Specific antibody concentrations (anti-CMV, anti-Hemophilus influenzae type B, anti-tetanus toxoid and anti-Streptococcus pneumoniae) decreased with median half-lives of 22.3–30.5 days. IgPro10 pharmacokinetics were similar in patients with CVID and XLA, although patients with CVID showed higher levels of anti-tetanus and anti-S. pneumoniae antibodies than patients with XLA, suggesting residual specific antibody production. IgPro10 pharmacokinetics fulfilled expectations for and were similar to intact IgG products. Administration of IgPro10 at 3- or 4-week intervals achieved sufficient plasma concentrations of total IgG, IgG subclasses and antibodies specific to important pathogens. [Copyright &y& Elsevier]

Abstract: Regions of HIV-1 gag between p2 and p6Gag/p6Pol, in addition to protease (PR), develop genetic diversity in HIV-1 infected individuals who fail to suppress virus replication by combination protease inhibitor (PI) therapy. To elucidate functional consequences for viral replication and PI susceptibility by changes in Gag that evolve in vivo during PI therapy, a panel of recombinant viruses was constructed. Residues in Gag p2/p7NC cleavage site and p7NC, combined with residues in the flap of PR, defined novel fitness determinants that restored replicative capacity to the posttherapy virus. Multiple determinants in Gag have a dominant effect on PR phenotype and increase susceptibility to inhibitors of drug-resistant or drug-sensitive PR genes. Gag determinants of drug sensitivity and replication alter the fitness landscape of the virus, and viral replicative capacity can be independent of drug sensitivity. The functional linkage between Gag and PR provides targets for novel therapeutics to inhibit drug-resistant viruses. [Copyright &y& Elsevier]

Human immunodeficiency virus type 1 (HIV-1) protease activity is targeted at nine cleavage sites comprising different amino acid sequences in the viral Gag-Pol polyprotein. Amino acid polymorphisms in protease and in regions of Gag, particularly p7NC and the C-cleavage site between p2 and p7NC, occur in natural variants of HIV-1 within infected patients. Studies were designed to examine the role of natural polymorphisms in protease and to identify determinants in Gag that modulate protease processing activity. Closely related Gag-Pol regions from an HIV-1-infected mother and two children were evaluated for processing in an inducible expression system, for protease activity on cleavage-site analogues, and for impact on replication by recombinant viruses. Gag-Pol regions displayed one of three processing phenotypes based on the appearance of Gag intermediates and accumulation of mature p24CA. Gag-Pol regions that were processed rapidly to produce p24CA resulted in high-level replication by recombinant viruses, while slow-processing Gag-Pol variants resulted in recombinant viruses that replicated with reduced kinetics in both T cell lines and peripheral blood mononuclear cells. Direct impact by Gag sequences on processing by protease was assessed by construction of chimeric Gag-Pol regions and by site-directed mutagenesis. Optimal protease activity occurred when Gag and Pol regions were derived from the same gag-pol allele. Heterologous Gag regions generally diminished rates and extent of protease processing. Natural polymorphisms in novel positions in p7NC and the C-cleavage site have a dominant effect on protease processing activity. Accumulation of Gag products after processing at the C site appears to delay subsequent cleavage and production of mature p24CA. [Copyright &y& Elsevier]

Deals with a study which examined virologic and immunologic responses for HIV-infected children treated with indinavir. Methods; Patient characteristics; Immunologic and virologic responses; Relationship between virologic response and repopulation of CD4 T cells; Analysis of immunologic responses in patients with transient virologic response.

Features a study on protease genotype, a variable in outcome to combination therapy for human immunodeficiency virus (HIV) type I infection, among protease inhibitor-naive children and adolescents who had received extensive treatment with reverse-transcriptase inhibitors. Response to therapy; Viral and immune response to therapy; Genetic relationship among viruses; Discussion.