The reinforcing actions of a serotonin-3 receptor agonist within the ventral tegmental area: evidence for subregional and genetic differences and involvement of dopamine neurons.

Studies from our laboratory indicated that local perfusion of the ventral tegmental area (VTA) with a serotonin-3 (5-HT(3)) receptor agonist increased dopamine (DA) neuronal activity and that the self-infusion of ethanol (EtOH) and cocaine into the posterior VTA could be inhibited with coadministration of a 5-HT(3) receptor antagonist. The study tested the hypothesis that activating 5-HT(3) receptors within the VTA produces reinforcing effects. The study also examined whether there were differences between Wistar rats and a line of rats selectively bred for high alcohol consumption with regard to the self-infusion of a 5-HT(3) receptor agonist within the VTA.

Longitudinal assessment of immune response and viral characteristics in HIV-infected patients with prolonged CD4(+)/viral load discordance.

Although suppression of HIV-1 RNA below the limit of detection is associated with optimal outcomes, many patients can maintain or increase their CD4(+) count for prolonged time periods in the presence of persistent low-level viremia. We followed seven patients with prolonged (>5 years) discordant CD4(+)/viral load (VL) responses on protease inhibitor (PI)-based highly active antiretroviral therapy (HAART) prospectively for 1 year to assess evolution of immune function, viral phenotype, replication capacity (RC), and resistance profile. Immune function was assessed by qualitative and quantitative measurement of cellular activation (CD38(+)HLA-DR(+) and CD38 antibodies bound per cell), and the interferon (IFN)-() ELISpot assay.

Prolonged CD4+ cell/virus load discordance during treatment with protease inhibitor-based highly active antiretroviral therapy: immune response and viral control.

Mechanisms that underly discordant CD4+ cell/virus load (VL) responses in patients who receive highly active antiretroviral therapy (HAART) were studied in 30 human immunodeficiency virus (HIV)-positive patients, in 3 groups. Discordant responders maintained CD4+ cell levels >200/mm(3) with stable or increasing trend, despite sustained VLs of 500-5000 copies/mL, for >2 years. Treatment-success patients had CD4+ cell counts >200/mm(3) with stable or increasing trend and VLs <50 copies/mL, for >2 years.

Immune reconstitution in human immunodeficiency virus-infected children receiving highly active antiretroviral therapy: a cohort study.

Background: Highly active antiretroviral therapy (HAART) has brought about rapid declines in HIV-1 RNA concentrations and an increase in CD4+ counts in HIV-1-infected children. These changes are often accompanied by clinical improvement; however, the extent to which immune reconstitution occurs is not known.

Design: We compared two cohorts (n = 35) of HIV-1-infected children to evaluate the effects of HAART on immune recovery.

Immunologic profile of human immunodeficiency virus-infected patients during viral remission and relapse on antiretroviral therapy.

A dissociation between plasma human immunodeficiency virus (HIV) RNA levels and CD4(+) cell counts has been reported in patients experiencing viral relapse while receiving antiretroviral therapy. This study compared patients with stable CD4(+) lymphocytes during viral relapse while receiving treatment with patients who had sustained virus suppression. Plasma HIV RNA levels, lymphocyte immunophenotyping, and T cell receptor excision circle (TREC) levels were measured.