PubMed · 3153576
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B Watt. 1986. Cryptosporidium--an important human enteric pathogen.. https://pubmed.ncbi.nlm.nih.gov/3153576/
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Infection of macaques with chimeric simian/human immunodeficiency virus (SHIV) expressing the envelope protein of HIV-1 provides a model system for studying HIV-1 infection in humans. To this end, four rhesus macaques (Macaca mulatta) were given a single intravaginal (IVAG) inoculation of cell-free SHIVSF33A and longitudinal samples of peripheral blood and lymph nodes were analyzed for viremia, antigenemia, and various T-cell populations. Rhesus macaques infected IVAG with SHIVSF33A demonstrated a dramatic decrease in the CD4(+) PBMC subset in the initial weeks after viral exposure, a time that corresponded to peak in plasma viremia and antigenemia. Within 4 months of SHIVSF33A inoculation, partial to complete rebound of the CD4(+) PBMC was seen in these animals. Notably, the regeneration of the CD4(+) subset was associated with regeneration of the naive T-cell population and was concordant with clearance of plasma viremia. DNA heteroduplex tracking assays revealed transmission of minor variants within the SHIVSF33A inoculum to the IVAG-inoculated animals. The cell-free SHIVSF33A inoculum as well as virus isolated from animals early after transmission used the chemokine molecule CXCR4 as the primary cellular coreceptor, demonstrating that viruses expressing envelope glycoproteins of the syncytia inducing (SI) phenotype can be transported across the vaginal mucosa. Although none of the animals has yet to develop clinical symptoms of simian AIDS (SAIDS), infectious virus and viral nucleic acids could be persistently isolated from each animal. Furthermore, animals transfused with blood from IVAG-infected macaques drawn 2 weeks after inoculation suffered a more profound and sustained CD4(+) T-cell loss, persistent plasma viremia, and the development of SAIDS in one animal, indicating that IVAG-passaged SHIVSF33A was pathogenic. Taken together, these results establish that a pathogenic CXCR4-utilizing SHIVSF33A species crossed the cervicovaginal mucosa. Different courses of infection in the IVAG versus transfusion animals suggest that host-mediated responses elicited upon transmission across mucosal barriers may serve to limit viral replication and delay disease progression in the IVAG-infected animals.
Liposomal formulations have been shown to alter the efficacy and toxicity profiles of anthracylines for patients with HIV-related advanced Kaposi's sarcoma (KS). Using decision-analysis models, the costs and cost-effectiveness of the two U.S. Food and Drug Administration (FDA)-approved liposomal formulations of these agents were estimated. Estimates of costs, effectiveness, and cost-effectiveness were derived from clinical trial data of separate, randomized phase III trials of pegylated liposomal doxorubicin (20 mg/m2 every 3 weeks) and liposomal daunorubicin (40 mg/m2 every 2 weeks). Clinical response rates were 59% for pegylated liposomal doxorubicin and 25% for liposomal daunorubicin. Despite higher acquisition costs for pegylated liposomal doxorubicin, total estimated costs of treatment for KS and chemotherapy-related hematologic toxicities were similar ($7,066 U.S. compared with $6,621 U.S. for liposomal daunorubicin). Cost-effectiveness profiles, defined as average costs per responder, favored pegylated liposomal doxorubicin ($11,976 U.S./responder versus $26,483 U.S./responder for liposomal daunorubicin), reflecting the higher reported response rate in the phase III trial. Sensitivity analyses suggested that the costs and cost-effectiveness results would not differ markedly when evaluated over a range of assumptions, including response rate, neutropenia rate, and dosage variations.
The second AIDS-defining condition diagnosed chronologically is referred to in this report as the secondary AIDS diagnosis. In this study, we examined survival following a secondary AIDS diagnosis using demographic and clinical factors known within 1 year before secondary AIDS diagnosis. In a prospective cohort of 2412 HIV-seropositive homosexual men observed in the Multicenter AIDS Cohort Study (MACS), 609 presented with a secondary AIDS diagnosis between January 1, 1988 and March 31, 1995. To analyze the data, we used survival analysis methods including the Kaplan-Meier product-limit estimator and extended Cox models that allow for nonproportional hazards. The median survival time after a secondary diagnosis was 10.3 months. Rapidity of progression from an initial AIDS diagnosis to a secondary diagnosis was not associated with survival. Drug treatment did not show a beneficial effect because of confounding by indication (i.e., selection bias) and limited efficacy on advanced disease of treatments available prior to 1995. However, a beneficial effect was captured by the use of calendar periods as a proxy measure for the relative exposure to drug treatments. Later calendar year of secondary diagnosis, secondary Kaposi's sarcoma, and higher CD4+ cell count were found to be significantly (p < .05) associated with longer survival time. However, secondary AIDS diagnosis was a significant factor only in the short term. Using secondary Pneumocystis carinii pneumonia as the reference diagnosis, the relative hazard of death 3 months after the time of secondary Kaposi's sarcoma diagnosis was 0.56 (95% confidence interval [CI] = 0.36-0.89) whereas the relative hazard after concurrently diagnosed multiple secondary illnesses was 2.06 (95% CI = 1.26-3.38). After approximately 1 year from the secondary diagnosis, the type of diagnosis was no longer significantly associated with survival.