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)

Replication of human immunodeficiency virus type 1 (HIV-1) is dependent on the viral Rev protein. This protein acts in concert with the cis-acting rev-responsive element present in intron-containing RNAs to facilitate nuclear export of these RNAs. Here we show that a cis-acting 219-nucleotide sequence from an unrelated "simple" retrovirus, Mason-Pfizer monkey virus (MPMV), enables Rev-independent HIV-1 replication. This sequence is present in an untranslated region near the 3' end of the MPMV genome. The MPMV element is also able to efficiently substitute for Rev in expression of Gag/Pol and Env proteins from subgenomic constructs. We hypothesize that the MPMV element functions by interacting with a cellular factor that plays a role in mRNA transport analogous to that of the Rev protein. It might be possible to exploit this element in the development of an HIV vaccine.
 ...
PMID:A small element from the Mason-Pfizer monkey virus genome makes human immunodeficiency virus type 1 expression and replication Rev-independent. 810 97

Synthetic peptides derived from influenza virus and human immunodeficiency virus were tested for their ability to promote the assembly of HLA-A2 and HLA-B51 molecules in T2 cell lysates. Specific assembly was detected by an enzyme-linked immunosorbent assay. The most significant HLA-A2 assembly was obtained in the presence of peptides known to be targets for HLA-A2-restricted cytotoxic T lymphocytes (influenza matrix M.58-66 and HIV Pol 476-484). Three of a batch of Nef peptides corresponding to epitopic regions for cytotoxic T lymphocytes, caused significant assembly of HLA-A2 (Nef 83-91, 137-145 and 144-153), but only at high concentrations (100 microM). As these peptides bound relatively weakly, it is unlikely that they are good candidates for HLA-A2-restricted CTL epitopes. Peptides matrix M.60-68, Nef 186-194, and Plasmodium falciparum sh.77-85 produced the most significant assembly of HLA-B51. These peptides have a dominant hydrophobic anchor residue (V, L. I) at position 9 that could occupy pocket "F". Our results also suggest that another hydrophobic residue (V, L) at position 3 or 4 may anchor to hydrophobic pocket "D" of HLA-B51. Proline at position 2 greatly increases HLA-B51 anchoring.
 ...
PMID:A simple assay for detection of peptides promoting the assembly of HLA class I molecules. 812 45

We have compared cytoplasmic CD4 mRNA accumulation, CD4 biosynthesis and steady-state levels of both CD4 protein and mRNA in a variety of clonal derivatives of U-937 cells, chronically infected with human immunodeficiency virus type 1 IIIB (HIV-1), that express various cellular and viral phenotypes. These phenotypes included defective processing of either gp160 or Gag-Pol, viruses with severely limited host-range, and inability to generate viral products. All clones, with the exception of the one that failed to generate viral mRNA and proteins, did not express cell surface CD4. Furthermore, each of these clones had steady-state levels of CD4 mRNA which were either equivalent to or higher than those of the parental U-937 cell line. Patterns of cytoplasmic CD4 mRNA levels resembled those of total RNA, suggesting that CD4 mRNA transport from the nucleus to the cytoplasm was unaffected by HIV-1 infection. Profiles of steady-state levels of the CD4 protein resembled those of CD4 mRNA in the UHC clones, but CD4 biosynthesis was reduced in all clones with the exception of that which failed to express viral products. This report is the first demonstration that steady-state CD4 biosynthesis is reduced in HIV-1-infected cells. In general, there was a good correlation between high levels of expression of gp160 and reduced CD4 biosynthesis. These results suggest that HIV-1 env gene products may contribute to the observed reduction in levels of CD4 biosynthesis.
 ...
PMID:Correlation between high level gp160 expression and reduced CD4 biosynthesis in clonal derivatives of human immunodeficiency virus type 1-infected U-937 cells. 815 1

Extremely high frequencies of the A nucleotide are found in the RNA genomes of the lentivirus group of retroviruses. It is presently unknown what molecular force is responsible for this A-pressure. In this manuscript, we demonstrate a correlation between this 'A-pressure' and the amino acid-usage of the lentivirus family. We compared the amino acid composition of the Gag and Pol proteins of the human immunodeficiency viruses type 1 and 2 (HIV-1 and HIV-2) with that of the second group of human retroviruses; the human T-cell leukemia viruses type I and II (HTLV-I and HTLV-II). Differences in total amino acid content correlate with the preference for A-rich codons in the HIV genome. A pair-wise comparison of homologous amino acid positions in the Pol proteins indicates that both conservative and non-conservative changes can be accounted for by this A-bias. The putative molecular mechanism underlying this A-pressure and the evolutionary consequences are discussed.
 ...
PMID:The unusual nucleotide content of the HIV RNA genome results in a biased amino acid composition of HIV proteins. 820 75

Virologic and immunologic studies were performed on five patients presenting with primary human immunodeficiency virus type 1 (HIV-1) infection. CD8+ cytotoxic T lymphocyte (CTL) precursors specific for cells expressing antigens of HIV-1 Gag, Pol, and Env were detected at or within 3 weeks of presentation in four of the five patients and were detected in all five patients by 3 to 6 months after presentation. The one patient with an absent initial CTL response had prolonged symptoms, persistent viremia, and low CD4+ T-cell count. Neutralizing antibody activity was absent at the time of presentation in all five patients. These findings suggest that cellular immunity is involved in the initial control of virus replication in primary HIV-1 infection and indicate a role for CTL in protective immunity to HIV-1 in vivo.
 ...
PMID:Temporal association of cellular immune responses with the initial control of viremia in primary human immunodeficiency virus type 1 syndrome. 820 39

Previous studies on electrochemical reduction of the HIV reverse transcriptase inhibitor, 3'-azido-3'-deoxythymidine (Zidovudine, AZT) and several of its analogues, have been extended to 2'-AZdT and two of the intracellular metabolites of AZT, the 5'-O-glucuronide (GAZT) and the 5'-phosphate (AZTMP). Also investigated were azido nucleosides with aglycons susceptible to electrochemical reduction, cytosine and adenine. The surface activities of these compounds at the mercury electrode were examined. In all instances, reduction of the azido group was a two-electron process, with conversion to an amino group. For an azido adenine nucleoside, it proved possible to reduce the azido group without affecting the aglycon. Electrochemical reduction is shown to provide a simple one-step synthesis of amino nucleosides from the available azido nucleosides. The reduced compounds, several hitherto unknown, are useful reference standards for following intracellular metabolism of azido nucleosides, and may also prove of interest as new potential antimetabolites.
Acta Biochim Pol 1993
PMID:Electrochemical reduction products of azido nucleosides, including zidovudine (AZT): mechanisms and relevance to their intracellular metabolism. 821 58

Antinociceptive activity of seven pentapeptide fragments of human adenovirus type 2 (Ad2) virion proteins: Thr-Val-Pro-Pro-Arg (1), Thr-Arg-Pro-Pro-Arg (2), Thr-Gly-Pro-Pro-Thr (3), Pro-Arg-Pro-Pro-Thr (4), Phe-Val-Pro-Pro-Arg (5), Ala-Arg-Pro-Pro-Ala (6), Tyr-Gly-Pro-Pro-Lys (7)--analogs of known tuftsin inhibitor Thr-Lys-Pro-Pro-Arg, was measured by hot-plate procedure. Also two tuftsin-like fragments of epitopes of HIV-1 and HIV-2: Thr-Lys-Ala-Lys (8), Thr-Lys-Glu-Lys (9), and tuftsin analog Thr-Lys-Asp-Lys (10) were tested. In the control experiments the effects of tuftsin and pentapeptide tuftsin inhibitor were also studied. The peptides 2, 4 and 5 were found to produce very strong analgesia after the icv injection. It was observed that pretreatment with peptide 8 remarkably diminished the antinociceptive effect induced by tuftsin.
Pol J Pharmacol
PMID:The analgesic activity of some tuftsin- and tuftsin inhibitor-like fragments of the viral coat proteins. 822 Jun 60

The product of the vpr open reading frame of human immunodeficiency virus type 1 (HIV-1) is a 15-kDa, arginine-rich protein that is present in virions in molar quantities equivalent to that of Gag. We report here the results of our investigations into the mechanism by which Vpr is incorporated into virions during assembly in infected cells. For these studies we used an expression vector encoding a Vpr molecule fused at its amino terminus to a nine-amino-acid peptide from influenza virus hemagglutinin. The tagged Vpr expression vector and a vpr mutant HIV-1 provirus were used to cotransfect COS cells, and the resulting virions were tested for the presence of the tagged protein on immunoblots probed with monoclonal antibody against the hemagglutinin peptide. The COS-produced virions were found to contain readily detectable amounts of tagged Vpr and smaller amounts of a putative tagged Vpr dimer. Infectivity of the particles was not altered by incorporation of tagged Vpr. Our results using this system in combination with mutant HIV-1 proviruses suggested that incorporation of Vpr into virions requires the carboxy-terminal Gag protein of HIV-1 (p6) but not gp160, Pol, or genomic viral RNA. In addition, analysis of mutated, tagged Vpr molecules suggested that amino acids near the carboxy terminus (amino acids 84 to 94) are required for incorporation of Vpr into HIV-1 virions. The single cysteine residue near the carboxy terminus was required for production of a stable protein. Arginine residues tested were not important for incorporation or stability of tagged Vpr. These results suggested a novel strategy for blocking HIV-1 replication.
 ...
PMID:Incorporation of Vpr into human immunodeficiency virus type 1 virions: requirement for the p6 region of gag and mutational analysis. 823 Apr 45

A case is described of a 62 years old patient in the initial stage of clinically overt HIV infection. The infection occurred probably 11 years earlier by means of blood transfusion during open heart surgery. The possible reasons for the long-term asymptomatic carriage of the virus and factors influencing the development of symptomatic HIV infection (AIDS) are discussed.
Pol Arch Med Wewn 1993 Jul
PMID:[Eleven year period of asymptomatic HIV infection in a patient after open heart surgery]. 823 8

Prevalence of HAV infection markers was studied in 100 drug addicts whose sera were collected between 1988 and 1989. Anti-HAV antibodies were found in 65 (65%) of the tested drug addicts and in 55% of the individuals serving as the control group. No correlation between the presence of HAV infection markers, and sex, duration of drug abuse or HIV status was seen. However, drug addicts with anti-HAV antibodies were older than those without these antibodies. There was no difference in a mean titre of anti-CMV and anti-HSV type 1 antibodies between the individuals with and without HAV infection markers. It suggests that the tested markers are specific for HAV infection.
Pol Tyg Lek
PMID:[Markers of hepatitis A infection in drug addicts]. 823 38


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