AIDS-related infections

The course of HIV disease in renal allograft recipients

The clinical course of HIV seropositive renal allograft recipients is ill defined. Thus, a retrospective analysis of mortality, morbidity and graft survival was performed in two groups of HIV-positive patients. Group 1 (nine patients), seropositive for an indefinite period of time prior to transplantation (eight i.v. drug abusers, one homosexual), all lost their grafts after a mean period of 23 +/- 11 months from chronic rejection (six), complicated by focal glomerular sclerosis and nephrotic syndrome in three cases, sepsis (two) and death with a functioning graft (one). Four patients died, two from sepsis, one from Kaposi's sarcoma and one from fluid overload. Of the remaining five patients, all on hemodialysis, one had AIDS and four were asymptomatic after a mean period of 44 months following graft failure. Prolonged hospitalizations for both infections and acute rejection were common. Group 2 (six patients) seroconverted in the perioperative period, and two had functioning allografts at 78 and 100 months post-transplant. Causes of allograft loss, patient death and infection-related complications were similar to those of group 1, but acute rejection was rare. In conclusion, HIV infection in renal allograft recipients was associated with poor allograft survival due mainly to rejection, mostly chronic, often complicated by glomerular sclerosis and nephrotic syndrome. Infectious complications requiring hospitalization were also increased.

Nonnucleoside pyrrolopyrimidines with a unique mechanism of action against human cytomegalovirus

Based upon a prior study which evaluated a series of nonnucleoside pyrrolo[2,3-d]pyrimidines as inhibitors of human cytomegalovirus (HCMV), we have selected three active analogs for detailed study. In an HCMV plaque-reduction assay, compounds 828, 951, and 1028 had 50% inhibitory concentrations (IC(50)s) of 0.4 to 1.0 microM. Similar results were obtained when 828 and 951 were examined by HCMV enzyme-linked immunosorbent assay (IC(50)s = 1.9 and 0.4 microM, respectively) and when 828 was tested in a viral DNA-DNA hybridization assay (IC(50) = 1.3 microM). In yield-reduction assays with a low multiplicity of infection (MOI), all three compounds caused multiple log(10) reductions in virus titer, and the activities of these compounds were comparable to the activity of ganciclovir (GCV; IC(90) = 0.2 microM). In contrast to the reduction of viral titers by GCV, the reduction of viral titers by 828, 951, and 1028 decreased with increasing MOI. Cytotoxicity in human foreskin fibroblasts and KB cells ranged from 32 to >100 microM. In addition, 828 (the only compound tested) was less toxic against human bone marrow progenitor cells than GCV. Time-of-addition and time-of-removal studies established that the three pyrrolopyrimidines inhibited HCMV replication before GCV had an effect on viral DNA synthesis but after viral adsorption. Compound 828 was equally effective against GCV-sensitive and GCV-resistant HCMV clinical isolates. Combination studies with 828 and GCV showed that the effects of the two compounds on HCMV were additive but not synergistic. Taken together, the data indicate that these pyrrolopyrimidines target a viral protein that is required in an MOI-dependent manner and that is expressed early in the HCMV replication cycle.

Stress and HIV disease progression: psychoneuroimmunological framework

Psychoneuroimmunology (PNI) is the study of the interrelationships among behavior, neural and endocrine function, and the immune system. PNI investigates the relationships among stress, physiological dysregulation, and health outcomes. Research has supported the theory that emotional distress and the resultant neuroendocrine activation can induce immune system suppression. This suppression has significant implications for disease susceptibility and progression. HIV disease and its extensive immunological consequences are explored within this framework. Potential physiological pathways that may mediate stress-induced dysregulation within the context of HIV disease are identified. Key HIV-related PNI research studies are reviewed and critically analyzed. Implications for nursing practice and research are discussed.

Effect of d-fenfluramine on the lymphocyte response of HIV+ humans

The objective of this study was to analyse the effect of d-dexfenfluramine (d-FEN) on the human lymphocyte response, in vitro. Experiments were designed to determine whether d-FEN augments specific human immune parameters associated with protection from opportunistic microbial pathogens and particularly focuses on d-FEN as a means by which to augment the function of CD8+ and CD4+ lymphocytes. Lymphocytes were examined for three reasons: (1) for their ability to inhibit the growth of Candida albicans; (2) for their ability to proliferate in response to a mitogen; and, (3) their cytokine profile (vis., production of IL-2, IFN-gamma and TNF-alpha). Peripheral blood mononuclear cells (PBMC) were obtained from 20 HIV+ patients. The patients were diagnosed as HIV+ within the past 0.5-9 years. d-FEN was found to augment the capacity of CD8+ lymphocytes to inhibit the growth of the opportunistic microbial pathogen, C. albicans. d-FEN enhanced the capacity of CD4+ lymphocytes to proliferate in response to the mitogen, Concanavalin A, and to increase the amount of IL-2 produced by CD4+ and CD8+ lymphocytes from AIDS patients. d-FEN increased the number of CD4+ and CD8+ lymphocytes that produced IFN-gamma from either non-AIDS or AIDS patients and increased the number of AIDS patient's CD8+ lymphocytes that produce TNF-alpha. These in vitro data suggest that d-FEN may be effective in enhancing immune function in immunocompromised individuals.

Structure-based design and synthesis of lipophilic 2,4-diamino-6-substituted quinazolines and their evaluation as inhibitors of dihydrofolate reductases and potential antitumor agents

The synthesis and biological activities of 14 6-substituted 2,4-diaminoquinazolines are reported. These compounds were designed to improve the cell penetration of a previously reported series of 2,4-diamino-6-substituted-pyrido[2,3-d]pyrimidines which had shown significant potency and remarkable selectivity for Toxoplasma gondii dihydrofolate reductase (DHFR), but had much lower inhibitory effects on the growth of T. gondii cells in culture. The target N9-H analogues were obtained via regiospecific reductive amination of the appropriate benzaldehydes with 2,4,6-triaminoquinazoline, which, in turn, was synthesized from 2,4-diamino-6-nitroquinazoline. The N9-CH3 analogues were synthesized via a regiospecific reductive methylation of the corresponding N9-H precursors. The compounds were evaluated as inhibitors of DHFR from human, Pneumocystis carinii, T. gondii, rat liver, Lactobacillus casei, and Escherichia coli, and selected analogues were evaluated as inhibitors of the growth of tumor cells in culture. These analogues displayed potent T. gondii DHFR inhibition as well as inhibition of the growth of T. gondii cells in culture. Further, selected analogues were potent inhibitors of the growth of tumor cells in culture in the in vitro screening program of the National Cancer Institute with GI50s in the nanomolar and subnanomolar range. Crystallographic data for the ternary complex of hDHFR-NADPH and 2,4-diamino-6-[N-(2', 5'-dimethoxybenzyl)-N-methylamino]pyrido[2,3-d]pyrimidine, 1c, reveal the first structural details for a reversed N9-C10 folate bridge geometry as well as the first conformational details of a hybrid piritrexim-trimetrexate analogue.

X-ray crystallographic studies of Candida albicans dihydrofolate reductase. High resolution structures of the holoenzyme and an inhibited ternary complex

The recent rise in systemic fungal infections has created a need for the development of new antifungal agents. As part of an effort to provide therapeutically effective inhibitors of fungal dihydrofolate reductase (DHFR), we have cloned, expressed, purified, crystallized, and determined the three-dimensional structure of Candida albicans DHFR. The 192-residue enzyme, which was expressed in Escherichia coli and purified by methotrexate affinity and cation exchange chromatography, was 27% identical to human DHFR. Crystals of C. albicans DHFR were grown as the holoenzyme complex and as a ternary complex containing a pyrroloquinazoline inhibitor. Both complexes crystallized with two molecules in the asymmetric unit in space group P21. The final structures had R-factors of 0.199 at 1.85-A resolution and 0.155 at 1.60-A resolution, respectively. The enzyme fold was similar to that of bacterial and vertebrate DHFR, and the binding of a nonselective diaminopyrroloquinazoline inhibitor and the interactions of NADPH with protein were typical of ligand binding to other DHFRs. However, the width of the active site cleft of C. albicans DHFR was significantly larger than that of the human enzyme, providing a basis for the design of potentially selective inhibitors.

Cryptococcal polysaccharides bind to CD18 on human neutrophils

CD18, the beta chain of the beta 2 integrin family of adhesion molecules, is associated with three different alpha chains (CD11a, -b, and -c) and is expressed on the surface of all types of leukocytes. CD18-containing molecules are up-regulated on the surface of neutrophils (polymorphonuclear cells [PMN]) in response to chemotactic agents and are implicated in mediating adhesion to an inflamed endothelium, which is a prerequisite to migration of PMN into infected tissues. In a previous study, we found that a cryptococcal culture filtrate (CneF), when injected into the bloodstream of mice to simulate the antigenemia in cryptococcosis, inhibits PMN accumulation at the site of an inflammatory stimulus. In the present study, we assessed the ability of CneF and its individual components, i.e., glucuronoxylomannan (GXM), galactoxylomannan (GalXM), and mannoprotein (MP), to interact with CD18 on human PMN. CneF labeled with 14C was shown to bind to human PMN in a dose-dependent manner. Pretreatment of PMN with anti-CD18, but not an isotype-matched control monoclonal antibody (MAb) or anti-CD11a MAb, blocked the binding of 14C-labeled CneF to PMN. In addition, CneF, GXM, and GalXM but not MP significantly blocked the binding of the anti-CD18 MAb to CD18 on the surface of unactivated and formyl methionyl leucyl phenylalanine-activated PMN as determined by indirect immunofluorescence staining and flow cytometric analysis. In the same experiments, the cryptococcal polysaccharides did not affect the binding of an anti-CD11a or anti-L-selectin MAb to the surface of PMN at 4 degrees C. The results suggest that CneF and its components GXM and GalXM bind to CD18 on human PMN. Based on our findings, we propose that CD18 is a possible molecular target of cryptococcal polysaccharides and that binding of the polysaccharides to CD18 has the potential to inhibit leukocyte infiltration into inflammatory sites.

Synthesis of non-nucleoside analogs of toyocamycin, sangivamycin, and thiosangivamycin: the effect of certain 4- and 4,6-substituents on the antiviral activity of pyrrolo[2,3-d]pyrimidines

A number of 4-substituted 7-(ethoxymethyl)- and 7-[(2-methoxyethoxy)methyl]pyrrolo[2,3-d]-pyrimidine-5-carbonitrile and -5-thiocarboxamide derivatives and several 7-substituted 4,6-diaminopyrrolo[2,3-d]pyrimidine-5-carbonitrile, -5-carboxamide, and -5-thiocarboxamide analogs related to the nucleoside antibiotics toyocamycin and sangivamycin were prepared and tested for activity against human cytomegalovirus (HCMV) and herpes simplex virus type 1 (HSV-1). Biologically, modifications at the 4-position were not well tolerated in cell culture, and in almost all cases no activity against HCMV or HSV-1 was observed. Furthermore, none of the compounds inhibited the growth of L1210 murine leukemic cells in vitro. In sharp contrast to the 4-substituted compounds, all of the 4,6-diamino 5-nitrile and the 5-thioamide analogs were active against HCMV, whereas the 5-carboxamides were inactive. The corresponding 4-amino 6-methylamino and 6-dimethylamino 5-nitrile analogs were inactive against HCMV, establishing that an amino group at both C-4 and C-6 is a likely requirement for antiviral activity. Overall, our results demonstrate that an amino group at C-4 and a thioamide moiety at C-5 of a 7-substituted pyrrolo[2,3-d]pyrimidine are essential for activity against HCMV, whereas a 4,6-diamino analog does not necessarily require a thioamide group at C-5 for activity against HCMV.

2,4-diamino-5-deaza-6-substituted pyrido[2,3-d]pyrimidine antifolates as potent and selective nonclassical inhibitors of dihydrofolate reductases

Fifteen novel nonclassical and two classical 2,4-diamino-6-(benzylamino)pyrido[2,3-d]pyrimidine antifolates were synthesized as potential inhibitors of Pneumocystis carinii, (pc) Toxoplasma gondii, (tg) rat liver (rl), and human (h) recombinant dihydrofolate reductases (DHFR). These analogues lack a 5-methyl substitution which has been shown to be important for increased hDHFR inhibitory activity. In addition, they contain a reversal of the C9-N10 bridge present in folates and most antifolates. The synthesis of the compounds involved the reaction of 2,4,6-triaminopyrimidine with the sodium salt of nitromalonaldehyde to afford the key intermediate 2,4-diamino-6-nitropyrido[2,3-d]pyrimidine (7), in a single step. Reduction of 7 to the 2,4,6-triaminopyrido[2,3-d]pyrimidine (8), followed by reductive amination with the appropriate benzaldehydes or phenylacetaldehydes afforded the target compounds. N9 methylation of these analogues was carried out using formaldehyde and sodium cyanoborohydride. The analogues demonstrated significant inhibition of pcDHFR and tgDHFR. N9 methylation significantly increased DHFR inhibitory potency. Compound 11, the 3'4'5'-trimethoxy-substituted analogue with a selectivity ratio of 9.4 for tgDHFR (compared to rlDHFR) was the most selective analogue of the nonclassical series. Compound 22, the N9 methyl 2'5'-dimethoxy-substituted analogue was the most potent analogue against tgDHFR (IC 50 = 6.3 nM) and was the second most selective analogue for tgDHFR (compared to rlDHFR) in the nonclassical series. The naphthyl-substituted analogues 23-25 were generally more potent against rlDHFR than against pcDHFR and tgDHFR. Selected analogues were also evaluated against Streptococcus faecium (sf) DHFR, Escherichia coli (ec) DHFR, Lactobacillus casei (lc) DHFR and tgDHFR with hDHFR as the mammalian reference, under slightly different assay conditions than those employed for rlDHFR. Analogues 11 and 22 had selectivity ratios of greater than 100 for tgDHFR (compared to hDHFR). Analogue 22 in particular, was the most selective analogue of the nonclassical series against tgDHFR (selectivity ratio = 303.5) with excellent potency (28 nM). Analogue 11, also displayed significant selectivity for sfDHFR (selectivity ratio = 4902). Compound 22 was evaluated in vivo for the inhibition of the growth of T.gondii trophozoites in mice, where at 50 mg/kg orally, it demonstrated distinct prolongation of survival without toxicity. Compounds 11, 12 and 21-23 were evaluated as antitumor agents in the National Cancer Institutes preclinical in vitro screening program. Compounds 12, 22, and 23 showed GI50s for tumor growth inhibition in the 10 -6 - 10 -7 M range.

Lipophilic antifolates as agents against opportunistic infections. 1. Agents superior to trimetrexate and piritrexim against Toxoplasma gondii and Pneumocystis carinii in in vitro evaluations

2,4-Diaminopteridines (21 compounds) and 2,4-diamino-5-methyl-5-deazapteridines (34 compounds) along with three 2,4-diamino-5-unsubstituted-5-deazapteridines and four 2,4-diaminoquinazolines, each with an aryl groups attached to the 6-position of the heterocyclic moiety through a two-atom bridge (either CH2NH, CH2N(CH3),CH2S, or CH2CH2), were synthesized and evaluated as inhibitors of the growth of Toxoplasma gondii in culture and as inhibitors of dihydrofolate reductase enzymes from T. gondii, Pneumocystis carinii, and rat liver. Exceptionally high levels of combined potency and selectivity as growth inhibitors of T. gondii and as inhibitors of the microbial enzymes relative to the mammalian enzyme were found among the 5-methyl-5-deazapteridines but not for the other heterocyclic types. Thirty of the 34 5-methyl-5-deaza compounds gave growth inhibition IC50 values lower than that of pyrimethamine (0.4 microM) with 14 compounds below 0.1 microM, values that compare favorably with those for piritrexim and trimetrexate (both near 0.02 microM). As inhibitors of T gondii DHFR, all but three of the 34 5-methyl-5-deaza compounds gave IC50 values in the order of magnitude with those of piritrexim (0.017 microM) and trimetrexate (0.010 microM), and 17 compounds of this group gave IC50 values versus P. carinii DHFR similarly comparable with those of piritrexim (0.031 microM) and trimetrexate (0.042 microM). Thirteen of these congeners gave both T. gondii growth inhibition and DHFR inhibition IC50 values of 0.10 microM or less, thus indicating facile penetration of the cell membrane. Eleven of these inhibitors of both T. gondii growth and DHFR have selectivity ratios (IC50 rat liver divided by IC50 T. gondii) of 5 or greater for the parasite DHFR. The highest selectivity ratio of nearly 100 belongs to the 5-methyl-5-deaza compound whose 6-substituent is CH2CH2C6H3(OCH3)2-2,5. This compound is over 10(3)-fold more selective for T. gondii DHFR than bridge homologue piritrexim (selectivity ratio 0.088), a compound now in clinical trials. The candidate with CH2NHC6H3(CH3)2-2,5 in the 6-position gave the highest P. carinii DHFR selectivity ratio of 4.0, which is about 60-fold more selective than trimetrexate (0.071) and 80-fold more selective than piritrexim (0.048) toward this enzyme. The 10 best compounds with respect to potency and selectivity includes six compounds bearing 2,5-disubstituted phenyl groups in the side chain (with little, if any, difference in effects of methyl, methoxy, or ethoxy), two side chains bearing 1-naphthyl groups, and two with 5,6,7,8-tetrahydro-1-naphthyl groups. Bridge groups represented in the 10 choice compounds are CH2NH, CH2N(CH3), CH2CH2, and CH2S. The high levels of both potency and selectivity among these agents suggest that in vivo studies now underway may lead to agents that could replace trimetrexate and piritrexim in treatment of toxoplasmosis and P. carinii pneumonia.

Molecular docking towards drug discovery

Fueled by advances in molecular structure determination, tools for structure-based drug design are proliferating rapidly. Lead discovery through searching of ligand databases with molecular docking techniques represents an attractive alternative to high-throughout random screening. The size of commercial databases imposes severe computational constraints on molecular docking, compromising the level of calculational detail permitted for each putative ligand. We describe alternative philosophies for docking which effectively address this challenge. With respect to the dynamic aspects of molecular recognition, these strategies lie along a spectrum of models bounded by the Lock-and-Key and Induced-Fit theories for ligand binding. We explore the potential of a rigid model in exploiting species specificity and of a tolerant model in predicting absolute ligand binding affinity. Current molecular docking methods are limited primarily by their ability to rank docked complexes; we therefore place particular emphasis on this aspect of the problem throughout our validation of docking strategies.

Synthesis of non-nucleoside analogs of toyocamycin, sangivamycin, and ++thiosangivamycin: influence of various 7-substituents on antiviral activity

A number of 7-substituted 4-aminopyrrolo[2,3-d]pyrimidine-5-carbonitrile, -5-carboxamide, and -5-thiocarboxamide derivatives related to the nucleoside antibiotics toyocamycin and sangivamycin were prepared and tested for their activity against human cytomegalovirus (HCMV) and herpes simplex virus type-1 (HSV-1). Treatment of 2-amino-5-bromo-3,4-dicyanopyrrole (1) with triethyl orthoformate followed by alkylation via the sodium salt method with a variety of alkylating agents furnished the corresponding 1-substituted pyrroles 2a-k. Ring annulation was achieved with methanolic ammonia affording the 7-substituted 4-amino-6-bromopyrrolo++-[2,3-d]pyrimidine-5-carbonitrile derivatives 3a-k. Debromination of 3a-k, via catalytic hydrogenation, gave the corresponding 7-substituted 4-aminopyrrolo[2,3-d]pyrimidine-5-carbonitrile analogs 4a-j,l. A selective reduction of 4-amino-6-bromo-7-allylpyrrolo[2,3-d]-pyrimidine-5-carbon ril e (3k) in zinc and acetic acid furnished 4-amino-7-allylpyrrolo-[2,3-d]pyrimidine-5-carbonitrile (4k). Conventional functional group transformations involving the 5-cyano group of 4 furnished the 5-carboxamide derivatives 5a-1 and the 5-thio-amide analogs 6a-l. A similar transformation of the aglycone of toyocamycin (4m) furnished the corresponding aglycone of thiosangivamycin (6m). Several of the new compounds (4-6a-ej-l) were evaluated for their ability to inhibit the growth of L1210 murine leukemic cells. Whereas a number of the carboxamide (5) and thioamide (6) derivatives had modest activity, the corresponding nitrile analogs (4) were all inactive. All compounds were tested for activity against HCMV and HSV-1. The non-nucleoside nitrile analogs 4a-m and carboxamide derivatives 5a-l were, with a few exceptions, essentially inactive against HCMV and HSV-1 and relatively nontoxic. In direct contrast, nearly all of the thioamide derivates 6a-1, including the aglycone of thiosangivamycin (6m), were good inhibitors of HCMV and HSV-1. Most were noncytotoxic in their antiviral concentration range. Cytotoxicity which was observed appeared to be a consequence of DNA synthesis inhibition. Several of these compounds, such as 6b,e, were particularly interesting inhibitors of HCMV with IC(50)'s ranging from 0.1 to 1.3 muM. The antiviral activity of both compounds was well separated from cytotoxicity in KB, HFF, and L1210 cells.

Vitality and growth in HIV-infected gay men

The emphasis in the psychosocial literature on Human Immunodeficiency Virus (HIV) has been placed, correctly, on the traumatic impact of AIDS in terms of mortality, bereavement, suicide, psychopathology, and coping with life amid enormous multiple stressors. However, an important aspect of the HIV epidemic has been paid only minimal attention: many HIV-positive gay men have experienced beneficial, or even life-transforming, aspects of their situation. Seven HIV-positive gay men are described here who have successfully integrated HIV into a framework of world- and self-beliefs that allows for coherence, stability, emotional vitality, and positive self-regard. Eight general characteristics of these men are presented. These men represent a subgroup from a sample of 19 subjects in a qualitative clinical interview study exploring how HIV-positive gay men ascribe meaning to AIDS and their own HIV infection [1].

1992 AAD Award for Excellence in Education: The Integrated Basic and Clinical Science Conference Series at the University of Texas Southwestern Medical Center

This article was written to share information concerning the establishment and implementation of a successful, integrated basic and clinical science conference series for resident trainees in dermatology. We discuss the underlying philosophy and describe the concepts employed in, and the dynamics that have resulted from, this educational experiment. Finally, we include the schedule and references for the 1993-1994 academic year.

Toxoplasmic encephalitis in the AIDS patient

Toxoplasmic encephalitis is recognized as a major cause of opportunistic infection of the central nervous system in patients with acquired immune deficiency syndrome (AIDS). Often this protozoal infection is benign, but in the AIDS patient it can cause life-threatening complications. Usually, toxoplasmic encephalitis is a latent infection activated in the brain in some 5% to 15% of AIDS patients. Treatment with oral antibiotics is effective, but relapse is common, and there may be permanent brain tissue damage with resultant neurological deficits. This article acquaints the rehabilitation nurse with the diagnosis and acute nursing care of toxoplasmic encephalitis. Rehabilitation nurses need to know about this chronic condition because rehabilitation is key to its successful long-term care and management.

Current status of HIV therapy: II. Opportunistic diseases

Infections and malignancies account for most deaths in patients with AIDS and will continue to do so as long as HIV-induced immunosuppression is progressive and irreversible. Co-trimoxazole has emerged as the preferred agent for prevention of Pneumocystis carinii pneumonia. As appropriate broad-spectrum agents are developed, multiple opportunistic pathogen prophylaxis could become effective.

Improved synthesis and biological evaluation of an acyclic thiosangivamycin active against human cytomegalovirus

We previously described the synthesis and in vitro antiviral activity of an acyclic thiosangivamycin analog (Gupta et al., 1989a). In order to extend these initial studies, a new, multi-gram synthesis of 4-amino-7-[(2-hydroxy- ethoxy)methyl]pyrrolo]2,3-d]pyrimidine-5-thiocarboxamide (compound 229) was achieved in 5 steps from the known 5-amino-2-bromo-3,4-dicyanopyrrole in good overall yield. In plaque reduction assays with HCMV, compound 229 had an IC50 of 7 microM; in yield reduction assays the IC90 was 25 microM. The compound was less active against MCMV, HSV-1, HSV-2, and least active against VZV. Concentrations of compound 229 up to 32 microM did not affect the growth of KB cells for incubation periods up to 72 h. At 100 microM, a prolongation in population doubling time from 21 h (untreated) to 35 h was noted. This inhibition, however, was reversible upon removal of the compound suggesting the inhibition was cytostatic rather than cytotoxic. Flow cytometric studies with compound 229 in HFF cells revealed an accumulation of cells in S phase and a concurrent loss of cells in G2/M phase, suggesting an early S phase blockage. We conclude there is adequate separation between antiviral activity and cytotoxicity to merit further work with this class of pyrrolopyrimidines.

AIDS acquired by drug consumption and other noncontagious risk factors

The hypothesis that human immunodeficiency virus (HIV) is a new, sexually transmitted virus that causes AIDS has been entirely unproductive in terms of public health benefits. Moreover, it fails to predict the epidemiology of AIDS, the annual AIDS risk and the very heterogeneous AIDS diseases of infected persons. The correct hypothesis must explain why: (1) AIDS includes 25 previously known diseases and two clinically and epidemiologically very different epidemics, one in America and Europe, the other in Africa; (2) almost all American (90%) and European (86%) AIDS patients are males over the age of 20, while African AIDS affects both sexes equally; (3) the annual AIDS risks of infected babies, intravenous drug users, homosexuals who use aphrodisiacs, hemophiliacs and Africans vary over 100-fold; (4) many AIDS patients have diseases that do not depend on immunodeficiency, such as Kaposi's sarcoma, lymphoma, dementia and wasting; (5) the AIDS diseases of Americans (97%) and Europeans (87%) are predetermined by prior health risks, including long-term consumption of illicit recreational drugs, the antiviral drug AZT and congenital deficiencies like hemophilia, and those of Africans are Africa-specific. Both negative and positive evidence shows that AIDS is not infectious: (1) the virus hypothesis fails all conventional criteria of causation; (2) over 100-fold different AIDS risks in different risk groups show that HIV is not sufficient for AIDS; (3) AIDS is only 'acquired,' if at all, years after HIV is neutralized by antibodies; (4) AIDS is new but HIV is a long-established, perinatally transmitted retrovirus; (5) alternative explanations disprove all assumptions and anecdotal cases cited in support of the virus hypothesis; (6) all AIDS-defining diseases occur in matched risk groups, at the same rate, in the absence of HIV; (7) there is no common, active microbe in all AIDS patients; (8) AIDS manifests in unpredictable and unrelated diseases; and (9) it does not spread randomly between the sexes in America and Europe. Based on numerous data documenting that drugs are necessary for HIV-positives and sufficient for HIV-negatives to develop AIDS diseases, it is proposed that all American/European AIDS diseases, that exceed their normal background, result from recreational and anti-HIV drugs. African AIDS is proposed to result from protein malnutrition, poor sanitation and subsequent parasitic infections. This hypothesis resolves all paradoxes of the virus-AIDS hypothesis. It is epidemiologically and experimentally testable and provides a rational basis for AIDS control.

Stochastic methods for short term projections of symptomatic HIV disease

We designed and implemented stochastic methods for short term projections of HIV disease at the local level, that accommodate various states or stages of the disease. We gave particular attention to projection of the number of patients with HIV disease who need care, when durations of stay in these various states depend on current methods for treating opportunistic infections. We consider two types of data as input to these projections. One concerns seroprevalence surveys conducted over time and from which we can obtain time series estimates of the numbers of HIV-infected individuals. The other is a reported time series of AIDS cases adjusted for delays in reporting. Several projections, with data from the City of Philadelphia, illustrate this method. In addition, we consider a Monte Carlo method for computing confidence bounds on a projection.

Current status of HIV therapy: II. Opportunistic diseases

Infections and malignancies account for most deaths in patients with AIDS--and will continue to do so as long as HIV-induced immunosuppression is progressive and irreversible. Options available for prevention and improved management of such diseases are changing as new agents emerge, new combinations of agents are developed, and new indications for available agents are identified.

AIDS epidemiology: inconsistencies with human immunodeficiency virus and with infectious disease

The newly defined syndrome AIDS includes 25 unrelated parasitic, neoplastic, and noninfectious indicator diseases. Based on epidemiological correlations, the syndrome is thought to be due to a new, sexually or parenterally transmitted retrovirus termed human immunodeficiency virus (HIV). The following epidemiological data conflict with this hypothesis. (i) Noncorrelations exist between HIV and AIDS; for example, the AIDS risks of infected subjects vary greater than 10-fold with their gender or country. Abnormal health risks that are never controlled as independent AIDS causes by AIDS statistics, such as drug addiction and hemophilia, correlate directly with an abnormal incidence of AIDS diseases. Above all, the AIDS diseases occur in all risk groups in the absence of HIV. (ii) American AIDS is incompatible with infectious disease, because it is almost exclusively restricted to males (91%), because if it occurs, then only on average 10 years after transfusion of HIV, because specific AIDS diseases are not transmissible among different risk groups, and because unlike a new infectious disease, AIDS has not spread exponentially since the AIDS test was established and AIDS received its current definition in 1987. (iii) Epidemiological evidence indicates that HIV is a long-established, perinatally transmitted retrovirus. HIV acts as a marker for American AIDS risks, because it is rare and not transmissible by horizontal contacts other than frequent transfusions, intravenous drugs, and repeated or promiscuous sex. It is concluded that American AIDS is not infectious, and suggested that unidentified, mostly noninfectious pathogens cause AIDS.