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)

The human colonic adenocarcinoma cell line HT29 can be infected with various isolates of human immunodeficiency virus type 1 (HIV-1) and type 2 (HIV-2). In some cases, the virus was able to perform its complete cycle of replication as demonstrated by the persistent production of mature viral particles in the cell-free culture supernatant. We have cultured HT29 cells chronically infected with the replicative strain HIV1-NDK in a chemically defined serum-free medium. Under these conditions, the cells were able to maintain a high level of viral replication, as demonstrated by reverse transcriptase activities and in situ hybridization studies. By indirect immunofluorescence labeling and electron microscopy, we observed that serum starvation was associated with the differentiation of HIV-1-infected HT29 cells into mucous-secreting cells resembling epithelial goblet cells of the colonic mucosa. These mucous-secreting cells, which accounted for 50% of the overall population, produced mature particles of HIV through their apical membrane in the vicinity of mucous granules. These data suggest that HIV-infected goblet cells in the colonic mucosa may produce the virus in the colorectal lumen; this could explain the route of transmission of HIV in the case of anal intercourse.
 ...
PMID:Replication and apical budding of HIV-1 in mucous-secreting colonic epithelial cells. 128 Jun 83

To persuade South Africa to abolish its apartheid policy several measures have been taken by the international community, including economic sanctions. The harm done by sanctions to the South African economy is obvious. As economic activity has slowed down, unemployment, especially in the black community, has risen. For the unemployed poverty and hunger are harsh realities while for those lucky enough to have jobs income remains quite high. Prostitution has become a way of redistributing income and for many families it is the only way to avoid starvation. With prostitution, however, has come AIDS: it is estimated that HIV infection is doubling every 5-8 months. On 1 calculation 85% of sexually active blacks could be infected with HIV by 1996; most would proceed to AIDS and die, leaving millions of children without parents. Although economic sanctions have speeded up some measure of reform in South Africa they are now harming the very people they were intended to help. Furthermore insidious voices are already being heard saying the government should stop all reform processes and anti-AIDS campaigns and just "sit it out" for the next few years. A further consequence of an ailing economy is the unavailability of funding for those who wish to curb the spread of AIDS via educational and other programs. [Full text]
 ...
PMID:Apartheid and AIDS. 257 92

During the past 20 years, millions of people have died in Cambodia as the result of violence, starvation, and preventable diseases. During this period, the public health system was also decimated as health professionals were killed. Efforts to provide health care were further stymied by inadequate training and low salaries that forced doctors to depend upon private practices in urban areas for their income. The health indicators in Cambodia reflect this situation, with life expectancy at 47 years for men and 49 for women, infant mortality at 120/1000 live births, child mortality at 190/1000, and maternal mortality at 9/1000 births. Malaria causes 5000-10,000 deaths each year, and the annual incidence of pulmonary tuberculosis is 250/100,000. The spread of HIV in South East Asia is also posing a major threat to Cambodia, and each month 300-400 people are injured or die as a result of the explosion of 1 of the 13 million land mines (scattered throughout the country of 9 million inhabitants). Many Cambodians suffer mental illness as a result of the decades of violence and displacement. Today Cambodians are struggling to reestablish their public health system with the help of international donor agencies, and there is hope that an appropriate and sustainable system will be in place within 10 years.
 ...
PMID:Cambodian health in transition. 764 May 94

Wasting may not be an inevitable consequence of HIV infection but may be a consequence of multiple nutritional insults that are additive without periods of replenishment in between. Protein energy malnutrition in AIDS patients may be consequential to underlying illness and concomitant to death as a result of that illness or may hasten a patient's demise, that is, starvation with fatal loss of body cell mass. Mortality is closely related to weight loss. Malnutrition may be a result of decreased intake, malabsorption, altered metabolism, or any combination of the three. Nutritional strategies to prevent PEM include appetite stimulation, early nutritional supplementation with oral supplements, and the diagnosis and treatment of malabsorption and underlying infections. More aggressive measures such as gastrostomy or jejunostomy tube placement and total parenteral feedings are still being evaluated. Nutritional supplementation to enhance the immune system or manipulate metabolism may be adjunctive to the above strategies. Early intervention and attention to nutritional status may have long-term benefits to patients with this disease.
 ...
PMID:Nutritional aspects of HIV infection. 808 74

Nutritional support of patients with HIV or acquired immune deficiency syndrome (AIDS) has many similarities to other disease states in that the same nutritional products and techniques are used. Some patients with HIV, and many with AIDS without secondary infection, experience a metabolic milieu similar to patients with cancer cachexia. In providing dietary counselling to the HIV patient, we encounter many of the obstacles that must be overcome to improve nutrition in cancer: anorexia, gastrointestinal discomfort, lethargy, and poor nutrient utilization, which limit the ability for nutritional repletion. When a secondary infection is superimposed on HIV, patients resemble more highly catabolic trauma patients or patients in the intensive care unit (ICU), where, despite aggressive efforts to feed, there is usually a net nitrogen wasting leading to the more rapid development of cachexia. However, even in this setting, feeding will limit substantially net catabolism when compared to total starvation. Because the nutritional needs of HIV patients vary greatly, individual strategies have to be designed as the patient moves through the stages of disease. Patients are generally able to consume adequate nutrition either as regular food or dietary supplements during the latency period of viral replication. Once secondary infections become prevalent, artificial diets administered by tube or by vein may be required during the period of active secondary infections, with dietary supplements often helpful during more quiescent periods. Patients with HIV are among the most challenging for clinicians providing nutritional support. Knowledge from treatment of patients with other diseases may be useful, but more data must be gathered on the unique aspects of aetiology and treatment of the anorexia, malabsorption, and ultimate wasting associated with AIDS.
 ...
PMID:Nutrition support and the human immunodeficiency virus (HIV). 811 86

Rat pheochromocytoma PC12 cells were permanently transfected with a plasmid vector, containing the tat gene of human immunodeficiency virus type 1 (HIV-1). Various clones were obtained showing the production of different levels of bioactive Tat protein (Tat) after transient cotransfection with an HIV-1 long terminal repeat-chloramphenicol acetyltransferase reporter plasmid. Under conditions of serum starvation, tat-positive PC12 clones expressing high levels of Tat showed a significantly (P < 0.05) higher proliferation rate with respect to both mock-transfected PC12 cells and tat-positive PC12 cells expressing lower levels of Tat. Moreover, all tat-positive PC12 cell clones showed a partial morphological differentiation into sympathetic-like neurons, when seeded in low density (5 x 10(3) cells/cm2) cultures. On the other hand, mock-transfected PC12 cells showed the round shaped morphology typical of untreated PC12 cells and displayed signs of neuronal differentiation only after treatment with 100 ng/ml of nerve growth factor. The addition of 5 micrograms/ml of anti-Tat monoclonal antibody to the culture medium of tat-positive PC12 cell clones almost completely blocked their increased proliferation rate (P < 0.05), but did not affect neuronal differentiation. A significant (P < 0.05) increase in cell proliferation was consistently observed in PC12 cells supplemented with low concentrations of Tat (5 to 25 ng/ml), whereas neuronal differentiation was hardly affected by exogenous Tat. Our data strongly suggest that Tat exerts a complex influence on the proliferation and differentiation of PC12 cells, and this might help in increasing understanding of the pathogenesis of the frequent neurological disorders observed in AIDS patients.
 ...
PMID:Influence of the human immunodeficiency virus type 1 Tat protein on the proliferation and differentiation of PC12 rat pheochromocytoma cells. 827 65

We test the hypothesis that human immunodeficiency virus (HIV)-related weight loss is accompanied by inappropriately large losses of fat-free mass (FFM). Our secondary aims were to examine whether FFM increases during weight gain and to compare several techniques for measuring FFM change. FFM was measured at intervals averaging 5 months in 21 AIDS patients by means of skinfold thickness (SF), dual-energy x-ray absorptiometry (DEXA), total body water (TBW), and bioelectrical impedance using the equation of the manufacturer of the equipment (BIA(EZComp)) and a published prediction equation (BIA(Segal)). The FFM content of weight loss was similar for SF (57%), DEXA (60%), TBW (55%) and BIA(EZComp) (65%), but the result from BIA(Segal) (78%) was higher. The results were close to predicted starvation values apart from the results with BIA(Segal), which were significantly higher than predicted values. Weight gain was also composed of a large proportion of FFM. There were large intermethod differences in measurements of absolute FFM, but for measuring changes in FFM, the bias between SF, DEXA, and TBW was minimal. The results of BIA vary with the prediction equation used. In this group of patients with the acquired immune deficiency syndrome (AIDS), weight loss was composed of a large proportion of FFM, but in general this is compatible with undernutrition as the underlying cause and does not support the hypothesis of excessive FFM catabolism in HIV disease. SF, DEXA, TBW, and BIA(Segal) show reasonable agreement for measuring body composition changes. This information should be considered in the design of future intervention studies for HIV-related wasting.
 ...
PMID:Longitudinal changes in body composition measured with a variety of methods in patients with AIDS. 905 20

AIDS-related Kaposi sarcoma (AIDS-KS) is the most common malignancy associated with HIV infection, with an incidence of 10-30% of all AIDS patients. As such, there have been a large number of AIDS-KS cell strains isolated and numerous studies conducted to elucidate the mechanisms of malignancy in this disease. We have reported histological grade associated differences in the ability of AIDS-KS cell strains to proliferate under conditions of minimal growth factor supplementation, with strains derived from high grade lesions having enhanced proliferation potential. Furthermore, we found that this difference in in vitro growth characteristics was not attributed to grade associated differences in autologous growth factor release. These current investigations explored the hypothesis that grade associated growth differences could be attributed to differences in the expression of the components of the IL-6 receptor, or expression/inducibility of the pleotrophic transcription factor NF-kappa B. We determined there were no significant grade associated differences in the expression of either component (IL-6R alpha chain or gpl30) of the IL-6 receptor. However, non-lesional oral derived cell strain lysates from AIDS-KS patients (n = 4) contained significantly lower concentrations of both components of the IL-6 receptor than AIDS-KS strains (n = 8) and lower concentrations of gp-130 than normal human oral derived fibroblasts (n = 2). Comparative analysis of sera concentrations of soluble components of the IL-6 receptor did not demonstrate significant differences between HIV+/KS+ (n = 7), HIV+/KS- (n = 9) and normal (HIV-/KS-) (n = 4) populations. Further, no differences were detected in the expression of NF-kappa B in AIDS-KS cell strains (n = 5) derived from both high and low histological grade lesions as compared to nonlesional AIDS-KS cell stain (n = 1) and normal human oral derived fibroblasts (n = 2) under conditions of: constitutive/proliferative growth, sera starvation, oxidative stress, and mitogen reintroduction after sera starvation. In conclusion, these investigations have eliminated two explanations for histological grade associated differences for in vitro growth potential of AIDS-related KS cell strains and further substantiated the lack of systemic paracrine cytokine/cytokine receptor effects in AIDS-KS pathogenesis.
 ...
PMID:Expression of interleukin-6 receptors and NF-kappa B in AIDS-related Kaposi sarcoma cell strains. 921 76

Although apoptosis is considered one of the major mechanisms of CD4(+) T cell depletion in HIV-infected patients, the virus-infected cells somehow appear to be protected from apoptosis, which generally occurs in bystander cells. Vpr is an auxiliary HIV-1 protein, which, unlike the other regulatory gene products, is present at high copy number in virus particles. We established stable transfectants of CD4+ T Jurkat cells constitutively expressing low levels of vpr. These clones exhibited cell cycle characteristics similar to those of control-transfected cells. Treatment of control clones with apoptotic stimuli (i.e., cycloheximide/tumor necrosis factor alpha (TNF-alpha), anti-Fas antibody, or serum starvation) resulted in a massive cell death by apoptosis. In contrast, all the vpr-expressing clones showed an impressive protection from apoptosis independently of the inducer. Notably, vpr antisense phosphorothioate oligodeoxynucleotides render vpr-expressing cells as susceptible to apoptosis induced by cycloheximide and TNF-alpha as the control clones. Moreover, the constitutive expression of HIV-1 vpr resulted in the upregulation of bcl-2, an oncogene endowed with antiapoptotic activities, and in the downmodulation of bax, a proapoptotic factor of the bcl-2 family. Altogether, these results suggest that low levels of the endogenous vpr protein can interfere with the physiological turnover of T lymphocytes at early stages of virus infection, thus facilitating HIV persistence and, subsequently, viral spread. This might explain why apoptosis mostly occurs in bystander uninfected cells in AIDS patients.
 ...
PMID:The HIV-1 vpr protein acts as a negative regulator of apoptosis in a human lymphoblastoid T cell line: possible implications for the pathogenesis of AIDS. 944 20

Wasting is a debilitating complication of the human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) and is a major cause of morbidity and mortality. The etiology of wasting in HIV/AIDS is complex and its origins are multifactorial. Both patterns of simple starvation and the more complex metabolic and endocrine alterations associated with stress and trauma have been described in patients with the AIDS wasting syndrome. Observations suggest that the pathophysiology of the wasting in individual patients with HIV/AIDS may vary according to the primary cause of wasting and underlying disease activity. Optimal treatment of the AIDS wasting syndrome will depend on a thorough evaluation of all possible contributing factors. This review addresses the pathophysiologic basis of weight loss in HIV/AIDS, based on the current literature.
 ...
PMID:The etiology of wasting in the human immunodeficiency virus and acquired immunodeficiency syndrome. 962 88


1 2 3 4 5 6 Next >>