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)

Covalent linkage of myristate (tetradecanoate; 14:0) to the NH2-terminal glycine residue of the human immunodeficiency virus 1 (HIV-1) 55-kDa gag polyprotein precursor (Pr55gag) is necessary for its proteolytic processing and viral assembly. We have shown recently that several analogs of myristate in which a methylene group is replaced by a single oxygen or sulfur atom are substrates for Saccharomyces cerevisiae and mammalian myristoyl-CoA:protein N-myristoyltransferase (EC 2.3.1.97; NMT) despite their reduced hydrophobicity. Some inhibit HIV-1 replication in acutely infected CD4+H9 cells without accompanying cellular toxicity. To examine the mechanism of their antiviral effects, we performed labeling studies with two analogs, 12-methoxydodecanoate (13-oxamyristate; 13-OxaMyr) and 5-octyloxypentanoate (6-oxamyristate; 6-OxaMyr), the former being much more effective than the latter in blocking virus production. [3H]Myristate and [3H]13-OxaMyr were incorporated into Pr55gag with comparable efficiency when it was coexpressed with S. cerevisiae NMT in Escherichia coli. [3H]6-OxaMyr was not incorporated, even though its substrate properties in vitro were similar to those of 13-OxaMyr and myristate. [3H]13-OxaMyr, but not [3H]6-OxaMyr, was also efficiently incorporated into HIV-1 Pr55gag and nef (negative factor) in chronically infected H9 cells. Analog incorporation produced a redistribution of Pr55gag from membrane to cytosolic fractions and markedly decreased its proteolytic processing by viral protease. 13-OxaMyr and 3'-azido-3'-deoxythymidine (AZT) act synergistically to reduce virus production in acutely infected H9 cells. Unlike AZT, the analog is able to inhibit virus production (up to 70%) in chronically infected H9 cells. Moreover, the inhibitory effect lasts 6-8 days. These results suggest that (i) its mechanism of action is distinct from that of AZT and involves a late step in virus assembly; (ii) the analog may allow reduction in the dose of AZT required to affect viral replication; and (iii) combinations of analog and HIV-1 protease inhibitors may have synergistic effects on the processing of Pr55gag.
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PMID:Incorporation of 12-methoxydodecanoate into the human immunodeficiency virus 1 gag polyprotein precursor inhibits its proteolytic processing and virus production in a chronically infected human lymphoid cell line. 200 42

A 31-year-old woman, heroin addict since ten years, and infected by the human immunodeficiency virus (HIV) since one year, was admitted to the intensive care unit for respiratory failure (PaO2 = 40 mmHg and PaCO2 = 14.8 mmHg, despite breathing pure oxygen). She had been followed up for 6 months for increasing dyspnoea due to chronic cor pulmonale for which no satisfactory explanation had been put forward. Artificial ventilation with 8 cmH2O positive end-expiratory pressure and 100% oxygen was completely inefficient. She died within a few hours. Postmortem lung biopsy revealed talc particles within interalveolar walls and alveolar macrophages as well as the expected alterations in blood vessels. Pulmonary hypertension due to talc microemboli is a well-known cause of respiratory failure in heroin addicts. Such a diagnosis should not be overlooked in a patient infected with HIV. Respiratory failure may not be only due to opportunist infections, or tumours related to the HIV infection.
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PMID:[Respiratory failure in a HIV seropositive heroin addict female]. 200 73

Hydrogen peroxide and oxygen radicals are agents commonly produced during inflammatory processes. In this study, we show that micromolar concentrations of H2O2 can induce the expression and replication of HIV-1 in a human T cell line. The effect is mediated by the NF-kappa B transcription factor which is potently and rapidly activated by an H2O2 treatment of cells from its inactive cytoplasmic form. N-acetyl-L-cysteine (NAC), a well characterized antioxidant which counteracts the effects of reactive oxygen intermediates (ROI) in living cells, prevented the activation of NF-kappa B by H2O2. NAC and other thiol compounds also blocked the activation of NF-kappa B by cycloheximide, double-stranded RNA, calcium ionophore, TNF-alpha, active phorbol ester, interleukin-1, lipopolysaccharide and lectin. This suggests that diverse agents thought to activate NF-kappa B by distinct intracellular pathways might all act through a common mechanism involving the synthesis of ROI. ROI appear to serve as messengers mediating directly or indirectly the release of the inhibitory subunit I kappa B from NF-kappa B.
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PMID:Reactive oxygen intermediates as apparently widely used messengers in the activation of the NF-kappa B transcription factor and HIV-1. 206 63

Undesired side effects and complications of gastrointestinal endoscopy and premedication are rare events. However, this is true only of endoscopic units with experienced investigators, modern equipment and monitoring. The complication rate of upper gastrointestinal endoscopy is about 0.1% with cardiopulmonary events predominating. The typical complication of colonoscopy is perforation, seen in 0.2%. The relevant ERCP specific complication is acute pancreatitis in about 1%, followed by acute cholangitis. The most serious complications of laparoscopy are hemorrhage from the liver biopsy site, bleeding from abdominal wall varices, and perforation of the colon. The cardiopulmonary mortality is low for upper gastrointestinal endoscopy as well as for colonoscopy (1 death/20,000 procedures). Premedication, chronic obstructive pulmonary disease, coronary heart disease, valvular heart disease and, last but not least, advanced age, must be considered risk factors for the development of complications of gastrointestinal endoscopy. Balanced indication, particularly in the elderly patient, should be the consequence. If possible, endoscopy should be performed without sedatives. If premedication is necessary, it should be used sparingly. Not only patients at high risk for the development of cardiopulmonary complications, but all patients undergoing endoscopy must be carefully monitored after premedication, during and after endoscopy. The non-invasive procedure of pulse-oximetry is appropriate for continuous monitoring of arterial oxygen saturation in patients with cardiopulmonary diseases, irrespective of their premedication status. Antibiotic prophylaxis is recommended in patients with valvular heart disease or prosthetic valves. Standardized cleaning and disinfection of the instruments is of great importance to avoid hepatitis B or HIV transfer.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Complications of diagnostic gastrointestinal endoscopy. 183 80

Oxygen-sulfur exchange at the C-4 carbonyl of several modified pyrimidine nucleosides, including 3'-azido-3'-deoxythymidine (AZT), is described in an effort to enhance the lipophilicity and, thereby, the delivery to the central nervous system of the sulfur analogues without compromising the anti-HIV activities of the parental structures. Preparation of 3'-azido-3'-deoxy-4-thiothymidine (3) proceeded from 4-thiothymidine (1) and utilized the same methodology developed for the initial synthesis of AZT. Thiation of 2',3'-didehydro-3'-deoxythymidine (4a) and 2',3'-didehydro-2',3'-dideoxyuridine (4c) was carried out with Lawesson's reagent on the corresponding 5'-O-benzoate esters, 4b and 4d, to give 5a and 5c, respectively. The latter, on alkaline hydrolysis, gave 2',3'-didehydro-3'-deoxy-4-thiothymidine (5b) and 2',3'-didehydro-2',3'-dideoxyuridine (5d), respectively. The same series of reactions were applied to the 5'-O-benzoate esters of 2',3'-dideoxyuridine (6a) and 3'-deoxythymidine (6b) to give 2',3'-dideoxy-4-thiouridine (7d) and 3'-deoxy-4-thiothymidine (7b), respectively. Characterization of the saturated and unsaturated thionucleosides included mass spectrometric studies. Under electron impact conditions, the thiated analogues gave more intense parent ions than the corresponding oxygen precursors. The lipophilicity of thymidine and the 3'-deoxythymidine derivatives are enhanced significantly, as indicated, by increases in corresponding P values (1-octanol-0.1 M sodium phosphate) upon replacement of the 4-carbonyl oxygens by sulfur. Compounds 5b, 5d, 7b, and 7d were evaluated for their effects on HIV-induced cytopathogenicity of MT-2 and CEM cells. Only 5b and 7b were moderately active in protecting both cell lines against the cytolytic effect of HIV. The inhibitory effects of analogues 5b, 5d, 7b, and 7d on thymidine phosphorylation by rabbit thymus thymidine kinase were evaluated. Only 3 showed moderate affinity (Ki = 54 microM) for the enzyme. The generally weak anti-HIV activities of the remaining thio analogues are consistent with correspondingly low susceptibilities to thymidine kinase phosphorylation as estimated from the respective Ki values of the synthetic nucleosides. However, the phosphorylation of the 5'-monophosphate derivatives to their respective 5'-triphosphates must also be considered in connection with the weak in vitro anti-HIV effects of these thiated compounds.
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PMID:Synthesis and in vitro evaluation of some modified 4-thiopyrimidine nucleosides for prevention or reversal of AIDS-associated neurological disorders. 215 6

The clinical presentation of 60 consecutive Pneumocystis carinii pneumonias in 58 HIV-infected patients (48 men, 10 women, mean age 34 [22-53] years) was prospectively evaluated from April to August 1989 and compared with 60 consecutive P. carinii pneumonias in 59 HIV-infected patients (55 men, 4 women, mean age 37.5 [22-60] years) between 1981-88. Mortality rates within 14 days after diagnosis of P. carinii pneumonia were 50% (8 of 16 patients) until 1985, 20.5% (9 of 44) between 1986 and August 1988, and 1.7% (one of 60) in 1989. The degree of severity of the pneumonias at time of diagnosis was markedly lower in 1989, as shown by following parameters (averages of 1989, compared with averages of 1981-88): lactate dehydrogenase 540 (250-1419) U/l versus 680 (235-1920) U/l (not significant); alveolo-arterial difference of partial oxygen tension (pA-aO2) 22.9 (0.5-73.5) mmHg versus 39.7 (19-70) mmHg (P less than 0.001); score of radiological findings 1.4 (0-3) versus 2.7 (0-4) (P less than 0.001). In 1989, mainly clinical symptoms (dry cough: 57 of 60 cases, dyspnea: 44 of 60 cases, fever: 43 of 60 cases) initiated the diagnostic procedure: chest radiographs, lactate dehydrogenase and pA-aO2 were normal in 13, 25 and 33 episodes, respectively. The lower mortality rate of P. carinii pneumonia could not primarily be explained by therapeutical progress since the treatment of choice did not change fundamentally since 1981. Above all, early diagnosis fundamentally determined the probability of survival.
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PMID:[Pneumocystis carinii pneumonia in HIV infection: better prognosis because of early diagnosis]. 222 63

Respiratory failure secondary to Pneumocystis carinii pneumonia (PCP) is associated with high mortality in AIDS patients. In a search for prognostic indicators, we reviewed hospital charts of 13 AIDS patients admitted to our intensive care service from 1982 to 1989. Mortality rate was higher from 1982 to 1987 (4/5 patients) than later (3/8 patients). There was no significant difference between survivors and non survivors of this acute episode with regard to sex. HIV risk factors, time elapsed since AIDS diagnosis, vital signs (blood pressure, heart rate, respiratory rate), hemoglobin, white blood cell count, platelets, total and T4 lymphocytes, electrolytes, lactate dehydrogenase, P24 antigen Apache II and SAPS scores and corticosteroid treatment. Higher mortality was associated with more advanced age and an oxygen alveolar-arterial gradient greater than 65 mm Hg with an inspired fraction of oxygen of 0.21. We conclude that only the alveolo-arterial gradient could represent a prognostic indicator of practical interest. It is our belief that improvement since 1988 can be explained by earlier diagnosis and prompt treatment before development of severe lung alterations.
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PMID:[Survival of HIV-positive patients hospitalized in intensive care for respiratory insufficiency and pneumocystis carinii pneumonia]. 227 Apr 46

Bronchoalveolar lavage was used in 170 immunocompromised patients for detection of causative agents. Pneumocystis carinii was isolated 18 times from HIV-positive patients and 14 times from patients suffering from immunodeficiencies due to various other diseases. Patients with AIDS were in better clinical condition, had fewer infiltrates on chest x-ray, a higher oxygen partial pressure and lower LDH-plasma concentration than HIV-negative patients. In spite of the earlier stage of the disease patients with AIDS experience prodromal symptoms for a longer time and the number of isolated pneumocystis was larger. Mortality in AIDS patients was significantly lower than in patients with other causes of immunodeficiency.
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PMID:[Pneumocystis carinii pneumonia in HIV-positive and HIV-negative patients]. 233 26

Oligodeoxynucleotides with a phosphorus atom in which one of the non-bridging oxygen atoms is substituted by selenium were prepared and investigated with respect to their antisense properties. A general synthesis of phosphoroselenoate analogs of oligonucleotides is described using potassium selenocyanate as the selenium donor. The compounds, characterized by 31P NMR, were shown to decompose to phosphate with a half-life of ca. 30 days. Melting temperatures of duplexes between poly(rA) or poly(rI) with oligo(dT) and oligo(dC), respectively, indicate diminished hybridization capability of phosphoroselenoate oligomers relative to both the unmodified phosphodiester oligomers and the phosphorothioate congeners. A phosphoroselenoate 17-mer is a sequence specific inhibitor of rabbit beta-globin synthesis in wheat germ extract and in injected Xenopus oocytes. In contrast phosphoroselenoate analogs are potent non-sequence specific inhibitors in rabbit reticulocyte lysate. In vitro HIV assays were carried out on a phosphoroselenoate sequence and compared with a phosphorothioate analogue that has previously been shown to exhibit anti-HIV activity (Matsukura et al., Proc. Natl. Acad. Sci. (1987) 84, 7706-7710). The phosphoroselenoate was somewhat less active, and was much more toxic to the cells.
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PMID:Phosphoroselenoate oligodeoxynucleotides: synthesis, physico-chemical characterization, anti-sense inhibitory properties and anti-HIV activity. 268 24

Myristoyl-CoA:protein N-myristoyltransferase (NMT; EC 2.3.1.97) catalyzes the cotranslational linkage of myristate to the N-terminal glycine residues of several cellular, viral, and oncoproteins. We have recently synthesized a series of sulfur- and oxygen-substituted analogs of myristic acid that are similar in length to the 14:0 fatty acid yet have hydrophobicities equivalent to dodecanoate or decanoate. Previous in vitro enzyme assays and metabolic labeling studies indicate that some of these analogs are excellent substrates for NMT and are incorporated into subsets of cellular N-myristoyl proteins. Their sequence-specific incorporation probably arises from cooperative interactions between the acyl CoA and peptide binding sites of NMT. The human immunodeficiency virus 1 (HIV-1) and Moloney murine leukemia virus (MoMLV) depend on myristoylation of gag polyprotein precursors for assembly. We have tested four analogs--12-methoxydodecanoic acid, 10-propoxydecanoic acid, 5-octyloxypentanoic acid, and 11-ethylthioundecanoic acid--for their ability to block replication of these retroviruses. All reduce HIV-1 replication when incubated with CD4+ H9 cells for 10 days at 10-100 microM. 12-Methoxydodecanoic acid is most effective, producing a concentration-dependent decrease in (i) reverse transcriptase activity (to levels that were 5-10% of control at 20-40 microM), (ii) p24 levels, and (iii) syncytia formation. This degree of inhibition of HIV-1 replication is equivalent to that seen with 5 microM 3'-azido-3'-deoxythymidine and is accomplished without apparent toxicity, as measured by cell viability, protein, and nucleic acid synthesis. 5-Octyloxypentanoic acid inhibits MoMLV assembly in a dose-dependent fashion without accompanying cellular toxicity, while 12-methoxydodecanoic acid has no effect. These data suggest that the use of cellular NMT activity to deliver analogs of myristate with altered physical-chemical properties to proteins that undergo this cotranslational modification may represent an effective anti-viral therapeutic strategy as well as a way to investigate the role of covalently bound fatty acid in viral assembly.
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PMID:Replication of human immunodeficiency virus 1 and Moloney murine leukemia virus is inhibited by different heteroatom-containing analogs of myristic acid. 281 17


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