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

Between April, 1989, and August 1990. in Busia, Siaya, Kisumu, and South Nyanza districts of Western Kenya, health workers recruited 144 sputum smear positive tuberculosis (TB) cases and 432 age, sex, and neighborhood matched controls. They also recruited 132 newly detected leprosy cases and 384 matched controls. Researchers wanted to determine the association between HIV-1 and TB and between HIV-1 and leprosy. TB cases were more likely to be HIV-1 seropositive than were their controls, regardless of age (odds ratio = 4.9). Less than 30-year-old female TB patients were less likely to be HIV-1 seropositive than were less than 30-year-old male TB patients (OR, 2.8 vs. 8.1), while the opposite was true for older TB patients (OR, 19.6 vs. 2.6). Though not statistically different, the OR was greater for certain TB cases than for possible TB cases (13.7 vs. 3.5) and for BCG negative cases than for BCG positive cases (16.5 vs. 3.1). Etiologic fractions indicated that HIV infection was responsible for 31% of TB cases among males and 11% of TB cases among females. Overall, leprosy cases and controls had lower HIV seropositivity rates than did their TB counterparts (OR, 1.8 vs. 4.9). Even though none of the ORs for the association between HIV infection and leprosy were statistically significant from unity, the fact that ORs were greater than unity in all (1.4-2.4) but 1 group (5-29 year old females, OR = 0.5) indicated a possible trend towards positive association. Though not statistically different, polar lepromatous type of leprosy and the leprosy category of histopathologically confirmed cases had the highest ORs (3.7 and 1.9, respectively). Multibacillary leprosy cases had a higher OR than did paucibacillary leprosy (2 vs. 1.6).
 ...
PMID:A case control study on human immunodeficiency virus-1 (HIV-1) infection as a risk factor for tuberculosis and leprosy in western Kenya. 813 90

The host immune response of cell-mediated immunity, particularly that of cytotoxic T lymphocytes (CTLs), is a major immune defence mechanism which may provide resistance to a human immunodeficiency virus type 1 (HIV-1) spread leading to acquired immune deficiency syndrome (AIDS). To prevent the accompanying activity of HIV-1 proteins responsible for the loss of helper T-lymphocyte function, it is crucial to develop a live attenuated recombinant vaccine expressing only T- or both T- and B-cell epitopes. Here, we examined the expression of the HIV-1 Env protein V3 region (15 amino acids from Arg315 to Lys329) in Mycobacterium bovis BCG as a fused form with an extracellular alpha antigen of Mycobacterium kansasii. Balb/c mice inoculated with this recombinant BCG (rBCG), rapidly induced V3 peptide-specific CTLs. Target cell lysis was restricted to the murine class I major histocompatibility complex, H-2d. A similar CTL response was also elicited after Balb/c mice were immunized with the same rBCG even when pre-inoculated with non-recombinant BCG. Thus, the rapid induction of HIV-1-specific CTLs indicates that this vaccine may be a therapeutic approach to preventing progression to AIDS.
 ...
PMID:Cytotoxic T lymphocyte response in mice induced by a recombinant BCG vaccination which produces an extracellular alpha antigen that fused with the human immunodeficiency virus type 1 envelope immunodominant domain in the V3 loop. 814 98

The continuing presence of tuberculosis in the world and its reappearance in industrialized countries again emphasizes the need to maintain and reinforce tuberculosis control. Despite the existence of effective drugs, there are still, deplorably, nearly 20 million cases of active tuberculosis throughout the world, with at least 3 million deaths annually. Almost 1.7 billion people are infected with the Koch bacillus. These figures are approximate and probably underestimate the real situation, as precise epidemiological data are not available. The rules of tuberculosis control are reviewed in this article, with distinctions drawn between low prevalence countries, where the objective is to eradicate the disease, and high prevalence countries, where it must be contained and reduced as quickly as possible the interruption of the claim of transmission of tuberculosis and the necessary collective measures are described in turn. The role of new techniques, particularly those based on molecular biology, is discussed. The importance of case finding and treatment in groups at risk in France is underlined, as are the role of BCG and the importance of protective measures, particularly in hospitals and in vulnerable subjects. The association between tuberculosis and HIV is well-known, but the HIV epidemic does not seem to be the only reason for the current resurgence of the tuberculosis problem in France in particular.
 ...
PMID:[The campaign against tuberculosis in 1993. Imperatives and current perceptions]. 822 Nov 89

There has been significant progress on several candidate vaccines against HIV infection over the past few years, i.e., live recombinant virus vaccines, inactivated virus vaccines, and purified antigens (subunit vaccines). There have been many phase I studies in healthy volunteers uninfected with HIV, as well as phase II trials with high-risk uninfected volunteers. Most of them focused on productions of neutralizing antibodies and cytotoxic T lymphocytes (CTLs) against HIV Env proteins. In addition, host immune responses, particularly cell-mediated immunity, were shown to be a major immune defense mechanism which may provide resistance to HIV spread leading to AIDS, indicating the possibility to develop prophylactic vaccine which may prevent the onset of AIDS in HIV carriers. However, various studies have implicated the concurrent activities of several HIV proteins, such as Env gp120, Env gp41, Tat, and Nef, in the induction of immunodeficiency. Therefore, the role of HIV-1 proteins in inducing immunodeficiency after HIV vaccination should be considered. Here, I introduce a recombinant BCG (rBCG) vaccine which expresses the immunodominant gp120 epitope. The tuberculosis vaccine strain Mycobacterium bovis BCG is a widely used vaccines with a low rate of serious complications. To develop a vaccine expressing an immunodominant epitope in the gp120 V3-loop, we used our system to express and secrete an epitope which was fused with an extracellular alpha antigen of Mycobacterium kansasii. Balb/c mice inoculated with this rBCG, rapidly induced HIV-specific CTLs. Target cell lysis was restricted to the murine class I major histocompatibility complex, H-2d.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:[HIV vaccine trials]. 822 64

It has been shown recently that BCG can be used as a live recombinant vaccine to stimulate immune responses. Proliferative or cytotoxic T-cell responses against several viral proteins such as HIV Gag, Env or Nef were obtained after parenteral immunization with BCG expressing these proteins. Antibody responses were also obtained after immunization of mice with recombinant BCG strain which expressed lac Z under the control of a promoter sequence isolated from Mycobacterium paratuberculosis. We have used this recombinant vaccine in guinea-pigs to investigate the influence of various routes of immunization on the immunogenicity of a foreign antigen expressed by recombinant BCG. Guinea-pigs were immunized by oral, respiratory or intradermal routes and proliferative responses, delayed-type hypersensitivity and antibody responses specific for beta-galactosidase were followed for 16 weeks. Results demonstrated that humoral and cellular immune responses specific for beta-galactosidase can be produced in all groups of guinea-pigs. However, the respiratory and especially the oral route of administration induced higher local and systemic immune responses than the intradermal route of immunization. Moreover, the oral immunization of mice with this recombinant BCG induced IgA responses which could be detected in both sera and intestinal secretions. Therefore, this study demonstrates for the first time that oral immunization with recombinant BCG can induce strong cellular and humoral immune responses.
 ...
PMID:Oral immunization with recombinant BCG induces cellular and humoral immune responses against the foreign antigen. 829 80

A 3-month-old infant with HIV-1 infection who recently immigrated from Ethiopia developed regional lymphadenitis and systemic symptoms subsequent to BCG immunization. She was suffering from axillary lymphadenitis ipsilateral to the BCG vaccination site, failure to thrive, unresolving fever and hepatosplenomegaly. Acid-fast bacilli were seen on staining and Mycobacterium bovis was isolated from the regional lymph node. The infant responded promptly to triple antituberculous therapy but died 2 months later from overwhelming pneumonia and respiratory failure. This case emphasizes the iatrogenic hazards of BCG immunization in HIV-1 infected infants. With the increasing prevalence of pediatric HIV-1 infection, indiscriminate BCG immunization programs should be reconsidered. While infants with asymptomatic HIV-1 infection at risk for tuberculosis should be immunized, BCG immunization should be withheld in those with symptomatic disease.
 ...
PMID:Mycobacterium bovis lymphadenitis complicating BCG immunization in an infant with symptomatic HIV-1 infection. 834 56

As the end of the twentieth century approaches new methods are needed for the treatment and control of tuberculosis. Vaccination needs to be rethought, and BCG either improved or replaced. Chemotherapy is no longer enough to meet the needs of impoverished countries, non-compliant patients, and increasingly drug-resistant organisms. The next major step forward should logically come from immunology. Following the clear differentiation of two pathways of cellular immune response to mycobacterial challenge, and the recent description of two functional types of helper T cells, ideas of what controls them have allowed the logical development of a potential new vaccine and a new immunotherapy. These are based on a killed environmental organism, Mycobacterium vaccae NCTC 11659. With this simple preparation together with chemotherapy we may be armed as never before to face the inevitable challenge that tuberculosis will present to the twenty first century. Parallels recognised between cell death in tuberculosis and infection with the human immunodeficiency virus open the possibility that the progress made in immunotherapy in tuberculosis might be applicable to HIV. If this proves the case then we may also have control over the latest, and worst, risk factor for tuberculosis at the time we need it most.
 ...
PMID:New concepts for the control of tuberculosis in the twenty first century. 837 52

Tuberculosis (TB) has long been under control in developed countries. Recently, however, the stability of this comfortable position has begun to erode. More than 7 million people are affected by active TB in developing countries where poor infrastructure thwarts control efforts and TB interacts with HIV infection. The 3 major strategies for controlling TB remain BCG vaccination in children, preventive therapy, and reducing the sources of infection through case identification and curative treatment. The international health community should confer high priority to research and resources upon improving these strategies. TB is highly prevalent in the tropics not because it is a tropical disease, but because it is an opportunistic disease of poverty, overcrowding, and malnutrition which are seen in higher incidence in tropical countries with relatively newly exposed populations and countries where health infrastructure is hindered by economic disadvantage and political instability. Sections review global trends; the size of the problem; tuberculosis in tropical Australia; tuberculosis and HIV infection; the current status of TB prevention; and the current status of case control.
 ...
PMID:Tuberculosis in the tropics. 837 94

Even before the onset of the HIV epidemic, studies reported large variations in the protective effect of BCG against TB. The current HIV/AIDS epidemic has increased the incidence of tuberculosis in many countries in sub-Saharan Africa. Thus, local estimates of the effectiveness of BCG are needed which take prevalence of HIV into account for planning strategies for vaccination and TB control programmes. A case control study was conducted in Lusaka, Zambia. The study included 116 TB cases and 154 hospital controls. Eighty-eight per cent of controls had BCG scars compared to 77 per cent of the cases. BCG was not associated with TB in HIV positive children (OR 1.0, 95 per cent CI 0.2, 4.6). However, there was 59 per cent protective effect (OR 0.41, 95 per cent CI 0.18, 0.92) in HIV negative children. The results also suggest an eight times higher risk of TB in HIV positive children.
 ...
PMID:HIV, BCG and TB in children: a case control study in Lusaka, Zambia. 841 15

Recommendations state that, where the risk of tuberculosis is high, BCG should be administered to infants as early in life as possible, even if the mother is known to be HIV-infected. BCG should be withheld from individuals with symptomatic HIV infections. However, continuing reports from sub-Saharan Africa and elsewhere of BCG complications in HIV-infected persons call for a re-assessment of current vaccination policies. For HIV-infected infants any benefit of BCG vaccination may be marginal because the prognosis is very poor. It is however not possible to exclude HIV-infected children from BCG vaccination at birth. HIV-uninfected infants born to HIV-infected mothers are at great risk of tuberculosis infection, which justifies routine vaccination. BCG rarely causes serious complications. Theoretically, persons with asymptomatic HIV infection may be at greater risk of complications from BCG vaccines, but available data are inconclusive in that respect. To vaccinate children with BCG at one year of age does not seem feasible and would increase the risk of tuberculosis especially for uninfected infants of HIV seropositive mothers. Available data seem to indicate that routine vaccination of newborns is indeed safe, even in areas with high prevalence of HIV infection.
 ...
PMID:Use of BCG in high prevalence areas for HIV. 852 87


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>