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Query: UMLS:C0019693 (HIV)
 170,526 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cytomegalovirus (CMV) is a major cause of inflammatory organ disease in immunosuppressed persons. To elucidate the mechanisms of CMV-induced inflammation, we investigated whether tumor necrosis factor-alpha (TNF-alpha) was involved in the pathogenesis of CMV colitis in patients with AIDS. In in situ hybridization experiments, TNF-alpha mRNA was shown to be abundantly present in colonic mucosa from AIDS patients with CMV colitis but not in colonic mucosa from control (AIDS and normal) subjects. The TNF-alpha transcripts, identified in macrophage-like cells containing cytomegalic inclusions, were positively associated with CMV, but not HIV-1, within the mucosa. In in vitro experiments, a patient-derived isolate of CMV, but not HIV-1Ba-L, induced human monocytes to express TNF-alpha mRNA and to release increased levels of TNF-alpha peptide following stimulation. CMV induction of TNF-alpha may play a critical role in CMV-induced inflammation and, since TNF-alpha upregulates expression of HIV-1, offers a mechanism by which CMV could serve as a co-factor for HIV-1 expression without both viruses infecting the same cell.
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PMID:Cytomegalovirus induction of tumor necrosis factor-alpha by human monocytes and mucosal macrophages. 133 Nov 70

Previous studies have indicated that most HLA-A2-binding peptides are 9 amino acid (aa) residues long, with a Leu at position 2 (P2), and a Val or Leu at P9. We compared the binding properties of different peptides by measuring the rate of dissociation of beta 2-microglobulin from peptide-specific HLA-A2 complexes. The simplest peptide that we identified that could form HLA-A2 complexes had the sequence (in single letter aa code) GLFGGGGGV, indicating that three nonglycine aa are sufficient for binding to HLA-A2. To determine whether most nonapeptides that contained Leu at P2 and Val or Leu at P9 could bind to HLA-A2, we tested the binding of nonapeptides selected from published HIV and melanoma protein sequences, and found that six of seven tested formed stable HLA-A2 complexes. We identified an optimal antigenic undecapeptide from the cytomegalovirus gB protein that could form stable HLA-A2 complexes that contained apparent anchor residues at P2 and P11 (sequence FIAGN-SAYEYV), indicating that the spacing between anchor residues can be somewhat variable. Finally, we tested the importance of every aa in the influenza A matrix peptide 58-66 (sequence GILGFVFTL) for binding to HLA-A2, by using Ala-substituted and Lys-substituted peptides. We found that multiple positions were important for stable binding, including P2, P3, P5-P7, and P9. We conclude that the P2 and P9 anchor residues are of prime importance for peptide binding to HLA-A2. However, other peptide side chains (especially at P3) contribute to the stability of the interaction. In certain cases, the optimal length for peptide binding can be longer than 9 residues.
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PMID:Sequence motifs important for peptide binding to the human MHC class I molecule, HLA-A2. 133 Dec 39

We have evaluated the microbiologic output and clinical significance of the detection of cytomegalovirus in 111 bronchoalveolar lavage specimens from immunosuppressed patients with pneumonitis. The samples were simultaneously processed by conventional tube culture and the rapid shell-vial centrifugation culture assay. Cytomegalovirus was recovered from 30 specimens (27%). The rapid shell-vial procedure was more sensitive than the tube culture, but in two cases cytomegalovirus was isolated only in tube cultures. Cytomegalovirus was considered clinically significant in only 3 from 13 HIV positive patients. All culture positive, HIV negative patients received treatment with ganciclovir. However, ganciclovir was never used on culture negative, HIV negative patients and cytomegalovirus related morbi-mortality was not found in these patients. A prospective study is needed to conclude if a cytomegalovirus negative culture also has a treatment exclusion value in HIV positive patients.
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PMID:[Cytomegaloviruses in the bronchoalveolar lavage fluids of immunocompromised patients: microbiological results and clinical significance]. 133 84

CD8+ cell antiviral activity and cytomegalovirus (CMV) were investigated in vivo as possible cofactors influencing the outcome of HIV-1 infection. The role of CD8+ cell suppression of HIV replication was evaluated by depleting CD8+ cells in two infected chimpanzees by inoculation with monoclonal anti-CD8 antibodies. Two other infected animals were injected with chimpanzee CMV (CCMV)-infected human fibroblasts to determine if exposure to this virus would induce HIV replication. Treatment with anti-CD8 antibody resulted in recovery of virus from the CD4+ lymphocytes of one animal at 1, 4, and 6 months, and from a second animal at 1 month postinoculation. In contrast, virus had been recovered only once or not at all from these infected chimpanzees for 4 years prior to treatment. Similarly, HIV was recovered from the CD4+ cells of the two animals 2 to 3 months after inoculation of CCMV-infected fibroblasts but not after inoculation of control uninfected fibroblasts. These studies suggest that CD8+ cell-mediated suppression and the presence of other viruses (such as CMV) could act as cofactors in influencing the extent of HIV-1 replication in vivo and, possibly, progression to disease.
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PMID:HIV-1 expression in chimpanzees can be activated by CD8+ cell depletion or CMV infection. 133 78

The responsibility of HIV in the occurrence of AIDS is definitely established, but "cofactors" are strongly suspected to intervene, which would explain the difference courses followed by the disease in one patient or the other. Some of these cofactors are related to the host or result from his behaviour. Thus, age at the time of HIV acquisition and the patient's HLA group are associated with differences in the speed of progression towards AIDS. Attitudes that lead to reexposure to the virus by the sexual or intravenous routes shorten the duration of the asymptomatic phase. Other cofactors are environmental in nature. Among the infectious agents, cytomegalovirus and some mycoplasmas have been the object of the most through studies. The responsibility of some physicochemical substances, such as cocaine, vitamin D and corticosteroids, acting as cofactors of increasing severity, mostly rests on data obtained in vitro and need clinical confirmation in man. However, the study of cofactors already seems to be a promising line of research aimed at understanding AIDS and hence its therapeutic approach.
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PMID:[HIV cofactors in the course of AIDS]. 133 99

The authors have specified the following criteria for the withdrawal of embryonal tissue at their department: 1) only tissue from dead fetus is allowed to be used in neurotransplantation; 2) embryonal tissue is to be obtained after spontaneous abortions from volunteers or from women asking for artificial abortion; 3) the women should be informed about the curative purposes of embryonal tissue voluntary donorship and they must give a written consent; 4) decision on abortion should be separated from the use of embryonal tissue; 5) women should not know recipients; no payments should be made for tissue; 6) the donor is not permitted to impregnate in order to use embryos for research or clinical purposes; 7) sampling of BWR, HBsAG, anti-HIV, cytomegalovirus, herpes I and II is to be made for serologic examinations and that from the cervix for cultivation and sensitivity, as well as ultrasound verification of a germinal age is done in potential donors; 8) consent should be signed to embryonal brain transplantation by recipient or his legitimate deputy if the recipient is certifiable. The above criteria should protect both the donor and the recipient. The use of embryonal tissue cultures seems to be promising. In addition to legal and ethic problems, immunological problems and problems concerning the aseptic withdrawal of embryonal tissue are falling off.
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PMID:[The legal and ethical aspects of nerve tissue transplantation]. 133 6

Immunofluorescence and immunoperoxidase test directed against early viral antigens, and DNA-DNA hybridization were compared with viral isolation for their abilities to detect Cytomegalovirus (CMV) in the urine of 89 HIV infected patients. From the 100 urine samples collected, 70 were found positive by at least one method. Considering viral isolation as the "gold standard" technique, immunofluorescence and immunoperoxidase had a sensitivity of 92.3% and 88% respectively, with a specificity in both cases of 95%. DNA-DNA hybridization showed a sensitivity of 90% but with lower (60%) specificity. All of the three assays were effective in detecting CMV from urine and the technical advantage of each is discussed.
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PMID:Detection of cytomegalovirus in urine of HIV-infected patients by DNA-DNA hybridization comparison with virus isolation, immunofluorescence and immunoperoxidase. 133 14

HIV-1-related neurological diseases, excluding opportunistic infections and HIV encephalitis, are considered here. Most occur in severely immunosuppressed patients, with CD4 counts of under 200 x 10(6) l-1. Primary brain lymphoma and metastases from systemic non-Hodgkin's lymphoma, the second commonest cause of cerebral mass lesions in AIDS, are usually aggressive B cell tumours. Their poor median survival after treatment, compared with that of lymphomas in non-AIDS patients, seems related to systemic complications, particularly opportunistic infections. Kaposi's sarcoma produces neurological symptoms exceptionally. Cerebral infarction is often unrecognized clinically but large vessel arteritic occlusions may occur. Intracranial haemorrhages occur mostly in thrombocytopenic patients. Seizures are frequently referred to the neurologist; investigation may lead to a diagnosis of AIDS. Nearly 50% of patients with seizures have cerebral toxoplasmosis or cryptococcal meningitis; HIV-1 encephalitis is presumed to be the cause in 30%. A subacute or chronic vacuolar myelopathy with pyramidal and posterior column signs is the commonest form of spinal cord involvement in AIDS; its cause remains unknown. Peripheral nerve syndromes occur at all stages of HIV-1 infection. Distal symmetrical peripheral neuropathies are the most frequent, particularly a painful form with axonal atrophy, associated with CMV infection, and seen during ARC or AIDS. Mononeuritis multiplex due to vasculitis, CMV, or lymphoma and a serious lumbosacral polyradiculopathy due to CMV are infrequent. The commonest myopathy is due to zidovudine (AZT); it usually responds to drug withdrawal. The nature, prognosis and optimal management of most other myopathies is yet to be determined.
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PMID:Other neurological diseases in HIV-1 infection: clinical aspects. 134 49

In recent years, the antiviral armamentarium has expanded considerably. Currently available agents are virustatic, inhibiting specific steps in the process of viral replication. No agent is active against nonreplicating or latent viruses. Acyclovir is useful in the treatment of genital herpes, herpes simplex encephalitis, mucocutaneous herpetic infection, varicella infection in the immunosuppressed host, and herpes zoster infection in the normal and the immunosuppressed host. It can also be used for prevention of herpesvirus infection in immunocompromised patients. Ganciclovir is indicated for the treatment of cytomegalovirus retinitis in patients with acquired immunodeficiency syndrome (AIDS) and is effective in the management of organ-specific cytomegalovirus infection in other immunocompromised patients. Chronic hepatitis C and condyloma acuminatum due to human papillomavirus respond to therapy with interferon alfa-2b. Patients with human immunodeficiency virus infection and CD4 lymphocyte counts of less than 500 cells/mm3 should be treated with zidovudine. Amantadine is useful in a therapeutic and prophylactic role in the management of influenza A virus infection. With the expanded use of and indications for antiviral therapy, clinically significant resistance to these agents has been encountered with increasing frequency.
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PMID:Antiviral agents. 134 78

Interaction between herpesviruses and human immunodeficiency virus (HIV)1 is postulated in the progression of HIV disease. In order to evaluate the specific antibody responses directed to Epstein-Barr virus (EBV) and cytomegalovirus (CMV) and to provide serological evidence suggesting reactivation of these viruses able to accelerate the immunodeficiency, we studied IgA and IgG titres to EBV and CMV in the serum of HIV positive patients in relation to the CD4 cell number. The titres of IgG antibodies to EBV and the prevalence of IgG to CMV were significantly higher in HIV positive patients compared to control high risk HIV negative subjects. In HIV infected patients, anti-VCA IgG antibodies increased and anti-EBNA IgG antibodies decreased progressively in relation to the decline of CD4 cell number whereas anti-CMV IgG antibodies did not varied significantly at the same time. Anti-VCA IgA and anti-EA IgG antibodies were found uncommonly and with low titres. IgA antibodies to EA and CMV were not detected in any patient. The variations in EBV antibody response that we describe in HIV infection were previously reported in other immunodeficiency states and could be distinctive of these diseases.
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PMID:Antibodies to Epstein-Barr virus and cytomegalovirus in relation to CD4 cell number in human immunodeficiency virus 1 infection. 134 40


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