Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019693 (HIV)
 170,526 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Thailand experienced its first case of AIDS in 1984. Approximately 800,000 Thais were infected with HIV in 1995 and 1 million Thais became infected by the year 2000. There have been 5 major epidemic waves: among male homosexuals (started 1984-5), intravenous drug users (started 1988), female commercial sex workers (started 1989), male clients (started 1990), and housewives and the newborn (started 1991). Approximately 96 per cent of HIV-1 infected Thais carried recombinant subtype A/E, the rest carried B'. In a male seroconvertors cohort of 235 cases, median time to show CD4 <200 cells/microL was 6.8 years. Five years survival was significantly lower than that of the other subtype B seroconvertors study, i.e., 82 per cent compared to 90 per cent. Interestingly, 13.5 per cent of seronegative Thais showed homozygous SDF1-3'A polymorphism, which suggests that approximately one-tenth of Thais may become long-term non-progressors after HIV-1 infection. Primary HIV infection syndrome is rare among Thai patients (1.1%). In contrast, it was 50-90 per cent in Western cohorts. In early symptomatic patients, one-third developed pruritic pappular eruptions (PPEs). In advanced stage, disseminated tuberculosis, Pneumocystis carinii pneumonia (PCP), cryptococcosis, and esophageal candidiasis are commonly found. In Northern Thailand, however, Penicillium marneffei infection or penicillosis is more common than cryptococcosis. The recent understanding of HIV pathogenesis suggests that HIV eradication is unlikely to be achievable with current strategies. Several National HIV treatment guidelines including the Thai guideline have been recommended treatment with triple antiretroviral regimen when patients become symptomatics or CD4+ <200. Current development of antiretroviral therapy which includes new agents, new formulas, and pharmacokinetic enhancements, is directed to better potency, higher genetic resistant barrier, less pill burden, and once a day dosing. These will ultimately improve the adherence and the long-term effectiveness of antiretroviral treatment. In reality, however, although the cost of triple regimen is dramatically declining, many patients still can not afford it. Primary prophylaxis and early diagnosis and treatment of opportunistic infection should be considered in patients with CD4+ <200 cells/microL. Modified short course ZDV studies and donation campaigns for preventing mother-to-child transmission, clinical trials to investigate the best use of expensive anti HIV medications in a poor resource setting have been or are being conducted. Nine phase I/II HIV-1 vaccine trial protocols have been or are being tested. A phase III trial of gp120 subtype B/E (AIDSVAX, VaxGen) was started in 1999, a total of 2,500 volunteers will be enrolled, and interim analysis is planned for August 2002. Thai investigators are also participating in pre-clinical development of recombinant BCG and DNA vaccines. Multidisciplinary and multi-level approaches, both by the government and private sectors, have had a positive impact on the HIV epidemic as shown by the declining seroprevalence of HIV infection in Thai male conscripts, and of major sexually transmitted diseases in men. Nevertheless, more effort at the grass roots level is needed to ensure further success and sustainability of the control of the HIV epidemic in Thailand.
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PMID:Update on HIV/AIDS in Thailand. 1152 20

Mycobacterial infection occurs commonly in patients with acquired immune deficiency syndrome. Incubation of monocytoid cell line U937 cells, which was cotransfected HIV-1 long terminal repeat sequence (LTR) chloramphenicol acetyltransferase (CAT) plasmid and Tat expression plasmid, with Mycobacterium smegmatis, Mycobacterium avium, Mycobacterium bovis BCG and Mycobacterium tuberculosis resulted in enhancement of CAT production, indicating that these mycobacteria could activate LTR in this cell line. The amount of CAT in the cells coexisting with M. smegmatis was higher than that infected with other mycobacteria. The amounts of CAT production in the cells coculturing with M. avium and M. bovis BCG were intermediate. M. tuberculosis slightly stimulated CAT production. The amount of tumor necrosis factor (TNF)-alpha produced by transfected U937 cells was correlated with the amount of CAT production. The interleukin (IL)-1beta and IL-6 levels in the supernatant from coculturing with all species were similar. The antibody to TNF-alpha inhibited CAT production induced by mycobacterial infections. The anti-IL-1beta and anti-IL-6 antibodies, however, scarcely influenced stimulation of LTR by mycobacteria. In addition, U937 cells transfected with full length LTR CAT plasmid showed increased CAT production by activation with mycobacteria, but the cells transfected with mutant LTR CAT constructs from which the nuclear factor (NF)-kappaB binding site was deleted did not show activation. These findings indicated that activation of Mycobacterium-induced LTR CAT is NF-kappaB dependent. These findings suggested that activation of HIV-1 LTR by mycobacteria was mainly mediated by NF-kappaB-induced secondary release of cytokine TNF-alpha.
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PMID:TNF-alpha-mediated activation of HIV-1 LTR in monocytoid cells by mycobacteria. 1154 16

Mycobacterial infection is a common occurrence in patients with acquired immune deficiency syndrome. Incubation of U1, a chronically HIV-1-infected human promonocytic cell line, with Mycobacterium smegmatis, M. avium, M. bovis BCG and M. tuberculosis resulted in enhancement of p24 antigen release in the supernatant, indicating that these mycobacteria could activate HIV replication from this cell line. The amount of p24 in the culture infected with M. smegmatis was higher than in cultures infected with other mycobacteria. The amounts of p24 release in cultures infected with M. avium and M. bovis BCG were intermediate. M. tuberculosis slightly stimulated HIV replication. The amount of TNF-alpha produced by U1 cells was correlated with the amount of p24 antigen release. The IL-1beta and IL-6 levels in the supernatant from cultures infected with all species were the same. The antibody to TNF-alpha inhibited p24 release induced by mycobacterial infections. The anti-IL-1beta and anti-IL-6 antibodies, however, scarcely influenced stimulation of HIV replication by mycobacterial infection. These data suggested that activation of HIV replication by mycobacteria mainly occurred by secondary release of cytokine TNF-alpha.
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PMID:TNF-alpha-mediated multiplication of human immunodeficiency virus in chronically infected monocytoid cells by mycobacterial infection. 1155 51

The recombinant Mycobacterium bovis BCG (rBCG) vector-based vaccine secreting the V3 principal neutralizing epitope of human immunodeficiency virus type 1 (HIV-1) Japanese strain was reported to induce both humoral and cellular immune responses effectively [Proc. Natl. Acad. Sci. USA. 92 (1995) 10693]. The antigen-secreting rBCG system was applied to the V3 epitope of clade E HIV-1 in this study. The V3 sequence of 19 amino acids (aa) and 15aa fused with mycobacterial alpha-antigen was not secreted while 12aa and 11aa sequences were successfully secreted from BCG cells. Serum IgG from guinea pig which was immunized with 12aa epitope-secreting recombinant BCG neutralized the WHO reference strain as well as primary field isolates of clade E virus. The serum IgG could also neutralize Thai B (clade B') strains which possessed a conserved GPGQ motif in their V3 sequences. These data suggest that the rBCG construct secreting the 12aa epitope is implicated in the development of a prophylactic vaccine in Thailand in which both clade E and B' viruses are prevalent.
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PMID:Cross-clade neutralizing antibody production against human immunodeficiency virus type 1 clade E and B' strains by recombinant Mycobacterium bovis BCG-based candidate vaccine. 1173 43

The immune response is able to contain but not eliminate Mycobacterium tuberculosis. Antigens that are specific to M. tuberculosis can identify latent infection accurately even after BCG vaccination. Genes that are required for persistence of the organism have been identified and new drugs are being developed to disrupt their function. This offers the hope of shortened courses of therapy. New drugs are urgently needed for multidrug-resistant tuberculosis, particularly as some areas are reporting a high prevalence of fluoroquinolone resistance. The sputum smear is the standard rapid diagnostic test for pulmonary tuberculosis, but is frequently negative in HIV infection. The yield of smear can be increased by sputum induction and by concentration. Innovative methods of providing directly observed therapy have been devised. Preventive therapy is effective in HIV infection and probably improves survival. However, the duration of benefit of preventive therapy seems to be relatively short-lived. Effective long-term reduction of tuberculosis risk in HIV-infected patients can be achieved with highly active antiretroviral therapy.
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PMID:Advances in adult pulmonary tuberculosis. 1198 4

Tuberculosis is among the top ten causes of global mortality and affects low-income countries in particular. This paper examines, through a literature review, the impact of tuberculosis control measures on tuberculosis mortality and transmission, and constraints to scaling-up. It also provides estimates of the effectiveness of various interventions using a model proposed by Styblo. It concludes that treatment of smear-positive tuberculosis using the WHO directly observed treatment, short-course (DOTS) strategy has by far the highest impact. While BCG immunization reduces childhood tuberculosis mortality, its impact on tuberculosis transmission is probably minimal. Under specific conditions, an additional impact on mortality and transmission can be expected through treatment of smear-negative cases, intensification of case-finding for smear-positive tuberculosis, and preventive therapy among individuals with dual tuberculosis-HIV infection. Of these interventions, DOTS is the most cost-effective at around US$ 5-40 per disability-adjusted life year (DALY) gained. The cost for BCG immunization is likely to be under US$ 50 per DALY gained. Treatment of smear-negative patients has a cost per DALY gained of up to US$ 100 in low-income countries, and up to US$ 400 in middle-income settings. Other interventions, such as preventive therapy for HIV-positive individuals, appear to be less cost-effective. The major constraint to scaling up DOTS is lack of political commitment, resulting in shortages of funding and human resources for tuberculosis control. However, in recent years there have been encouraging signs of increasing political commitment. Other constraints are related to involvement of the private sector, health sector reform, management capacity of tuberculosis programmes, treatment delivery, and drug supply. Global tuberculosis control could benefit strongly from technical innovation, including the development of a vaccine giving good protection against smear-positive pulmonary tuberculosis in adults; simpler and shorter drug regimens for treatment of tuberculosis disease and infection; and improved diagnostics for tuberculosis infection and disease.
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PMID:Interventions to reduce tuberculosis mortality and transmission in low- and middle-income countries. 1198 8

Tuberculosis is one of the most frequent opportunistic infections in HIV-infected patients in developing countries. In some instances, manifestations of pulmonary tuberculosis precede all other HIV related signs and symptoms because of the high virulence of M. tuberculosis. In order to characterise the interaction between these two pathogens, clinical and immunological parameters in pulmonary tuberculosis patients with and without HIV infection were compared. Amongst newly diagnosed pulmonary tuberculosis patients the association of some of these changes with the clinical outcome were evaluated. Of these, 44% were co-infected with HIV. Pulmonary tuberculosis patients with HIV-1 presented more frequently with lymphadenopathy and diarrhoea than those without HIV-1. Peripheral blood CD4+ counts were significantly lower in patients with pulmonary tuberculosis with HIV-1 than those with pulmonary tuberculosis alone, P= 0.0292. Low CD4+ lymphocyte counts, lymphadenopathy and BCG scar absence could serve as indicators of HIV-1 infection in pulmonary tuberculosis (PTB) patients.
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PMID:Markers in HIV associated tuberculosis in Kenya. 1215 55

Coincubation of monocytoid cell line U937 cells cotransfected with HIV-1 LTR CAT plasmid and Tat expression plasmid, with Mycobacterium smegmatis, M. avium, M. bovis BCG and M. tuberculosis enhanced chloramphenicol acetyltransferase (CAT) production, indicating that these mycobacteria could activate the LTR in this cell line. The amount of CAT in the cells coincubated with M. smegmatis was higher than that infected with the other mycobacteria after 12, 24 and 48 hour time periods. However, the amount of CAT production in the cells cocultured with M. tuberculosis was higher than those coincubated with the other mycobacteria at 72 hours. These findings indicated that avirulent mycobacteria such as M. smegmatis may activate HIV replication at an early time and its effects are gradually decreased, while the effect of virulent M. tuberculosis increased gradually, and lasted for a long time resulting in an acceleration of HIV disease in patients.
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PMID:Changed activation of HIV-1 LTR in monocytoid cells by mycobacteria with temporal progression of infection. 1217 80

Tuberculosis (TB) infects at least one third of the global population and causes 8 million new cases and 3 million deaths annually. 300,000 of these deaths are to children under age 15 years. The resurgence of TB is due to poor case management compounded by the growing resistance of Mycobacterium tuberculosis to anti-TB drugs and the spread of HIV infection. The World Health Organization (WHO) Global TB Program's (GTB) priority is to increase the use of drug therapy to cure infectious cases, thereby preventing the spread of the disease. Effective drugs already exist, but they need to be used more widely. About 20 potential new vaccine candidates are currently in research and development, with new vaccine candidates or formulations becoming available on an almost weekly basis. Molecular scientists are also hoping to determine how M. tuberculosis evades drugs. BCG, the standard anti-TB vaccine, has been around for more than 70 years, and provides consistently high protection against the most severe forms of TB in children. However, BCG is only 0-80% effective against the adult form of the disease, that which is responsible for most TB cases and deaths. Current research and development efforts are focused upon making a safe vaccine out of M. tuberculosis, making BCG into a more dependably effective vaccine, using proteins secreted by M. tuberculosis to make a nonliving vaccine, and using M. tuberculosis genes as vaccines.
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PMID:Vaccine researchers rise to the challenge of resurgent TB. 1217 18

While there is concern that children with HIV infections may have decreased immune responses or experience adverse effects from immunization, the present state of knowledge finds that the benefits of immunization outweigh the risks. In 1987, the World Health Organization recommended that asymptomatic individuals with HIV infections should receive all of the Expanded Program of Immunization antigens according to schedule. Symptomatic individuals should not receive BCG. In Uganda, BCG is administered at birth or shortly thereafter, which should minimize adverse effects in HIV-infected infants. HIV-positive adults with symptoms should receive inactivated vaccines.
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PMID:Immunization and HIV / AIDS. 1228 9


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