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)

Healthy subjects were administered single oral doses of 800 mg or 400 mg 3-[2-(benzoxazol-2-yl)ethyl]-5-ethyl-6-methylpyridin-2(1H)-o ne (L-696,229), a nonnucleoside inhibitor of the human immunodeficiency virus-type 1 (HIV-1) reverse transcriptase (RT). Plasma or urine samples were collected over a period of 48 hr. Pooled plasma (0.5-6 hr) and urine (0-24 hr) samples were analyzed by HPLC-UV and HIV-1 RT inhibition assay using poly rC.dG as a template primer. The parent compound and several common metabolites were detected in both samples. The metabolic profiles were also similar to those obtained from a rat liver slice incubation with [3H]L-696,229. The in vitro metabolites were identified by NMR and MS as 5 alpha-hydroxyethyl- (major), 5,6-dihydrodiol-, 6'-hydroxy-, 6-hydroxymethyl-, and 5-vinyl analogs, and a benzoxazole ring hydrolysis product. Most of the significant metabolites in human plasma and urine were found to be identical to the in vitro metabolites, as established by HPLC-UV and MS. Hydrolysis of the plasma and urine with beta-glucuronidase/sulfatase indicated the presence of significant amounts of conjugates of the parent compound and 5 alpha-hydroxyethyl metabolite. Most of the other primary metabolites were also present in conjugated forms, albeit in small quantities. In addition, two secondary metabolites were isolated and identified from the hydrolyzed urine as 5-acetyl-6'-hydroxy- and 5 alpha-hydroxyethyl-6-hydroxymethyl- analogs.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Metabolism of 3-[2-(benzoxazol-2-yl)ethyl]-5-ethyl-6-methylpyridin-2 (1H)-one (L-696,229), an HIV-1 reverse transcriptase inhibitor, by rat liver slices and in humans. 751 52

We have developed a method by which a researcher can quickly alter the specificity of a trans hairpin ribozyme. Utilizing this PCR method, two oligonucleotides, and any target vector, new ribozyme template sequences can be generated without the synthesis of longer oligonucleotides. We have produced templates with altered specificity for both standard and modified (larger) ribozymes. After transcription, these ribozymes show specific cleavage activity with the new substrate beta-glucuronidase (GUS), and no activity against the original substrate (HIV-1, 5' leader sequence). Utilizing this technique, it is also possible to produce an inactive ribozyme that can be used as an antisense control. Applications of this procedure would provide a rapid and economical system for the assessment of trans ribozyme activity.
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PMID:Alteration of hairpin ribozyme specificity utilizing PCR. 758 Aug 97

From human urine the following metabolites of sulfamethoxazole (S) were isolated by preparative HPLC: 5-methylhydroxysulfamethoxazole (SOH), N4-acetyl-5-methylhydroxysulfamethoxazole (N4SOH) and sulfamethoxazole-N1-glucuronide (Sgluc). The compounds were identified by NMR, mass spectrometry, infrared spectrometry, hydrolysis by beta-glucuronidase and ratio of capacity factors. The analysis of S and the metabolites N4-acetylsulfamethoxazole (N4), SOH, N4-hydroxysulfamethoxazole (N4OH), N4SOH, and Sgluc in human plasma and urine samples was performed with reversed-phase gradient HPLC with UV detection. In plasma, S and N4 could be detected in high concentrations, while the other metabolites were present in only minute concentrations. In urine, S and the metabolites and conjugates were present. The quantitation limit of the compounds in plasma are respectively: S and N4 0.10 micrograms/ml; N4SOH 0.13 micrograms/ml; N4OH 0.18 micrograms/ml; SOH 0.20 micrograms/ml; and Sgluc 0.39 microgram/ml. In urine the quantitation limits are: N4 and N4OH 1.4 micrograms/ml; S 1.5 micrograms/ml; N4SOH 1.9 micrograms/ml; SOH 3.5 micrograms/ml; and Sgluc 4.1 micrograms/ml. The method was applied to studies with healthy subjects and HIV positive patients.
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PMID:Isolation, identification and determination of sulfamethoxazole and its known metabolites in human plasma and urine by high-performance liquid chromatography. 782 Feb 61

Envelope glycoproteins of human immunodeficiency viruses (HIV-1 and HIV-2) can interact with high-mannose glycans and with the mannosyl or N-acetylglucosaminyl core of complex-type oligosaccharidic structures. HIV-1 glycoproteins also specifically bind sulphated polysaccharides such as dextran sulphate (DS) and heparin. Here, we show that the latter property is shared by HIV-2 recombinant gp140 (rgp140) precursor glycoprotein. Binding of rgp140 and of corresponding rgp160 of HIV-1 to heparin- and DS-substituted (sulphated dextran beads; SDB) affinity matrices was inhibited by the soluble specific ligand and also by fetuin, asialofetuin or the anionic simple carbohydrate derivative mannose-6-phosphate (M6P). Interaction of HIV-1 rgp120 subunit with the two affinity matrices was also inhibited by M6P, but only rgp120 binding to heparin-agarose, and not that to SDB, was affected by fetuin and asialofetuin. These results suggest that HIV-1 and HIV-2 envelope glycoproteins presumably display different sulphated polysaccharide and carbohydrate recognition sites. Some of these may be common or in close proximity: with respect to rgp160, for example, the sites may be common on the gp41 moiety and/or in a region of gp120 which would be more accessible when expressed on rgp160 than on processed gp120, while they may be distinct on the cleaved gp120 subunit. Finally, because M6P is a marker of lysosomal enzymes, we verified that HIV-1 and HIV-2 envelope glycoproteins could specifically bind in a M6P-inhibitable manner to a representative lysosomal enzyme, bovine liver beta-glucuronidase coupled to agarose, suggesting that they may possibly interfere with lysosomal enzyme sorting in HIV-infected cells.
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PMID:Interactions of HIV-1 and HIV-2 envelope glycoproteins with sulphated polysaccharides and mannose-6-phosphate. 818 46

Recombinant HIV-1 Rev protein was overexpressed in Escherichia coli using translational coupling to the beta-glucuronidase gene and demonstrated to interact with high affinity and specificity with the Rev responsive element (RRE). A complex Rev-dependent binding pattern was observed using the gel shift assay which could be simplified to one or two primary bands in the presence of stoichiometric concentrations of RRE. Competition of these bands with a series of homopolymer RNA species demonstrated that Rev is essentially a poly-G binding protein, although poly-I was also shown to compete for specific RRE binding. The stoichiometry of the Rev-dependent gel shift complexes was determined using 125I-labeled Rev. The stable, lowest mobility complex was determined to possess a ratio of between 7 and 8 Rev molecules per RRE containing RNA fragment while the two fastest migrating complexes contained ratios of one and two Rev molecules per RRE, respectively. Using the Hill equation as a model for cooperative interactions, a Hill coefficient of n(app) = 2 was obtained from fitting of direct nitrocellulose filter binding assays, reflecting cooperatively bound Rev molecules on the RRE under equilibrium binding conditions. An increase in ionic strength from 0.0 to 0.3 M NaCl reduced cooperative Rev binding to the RRE, but specificity of Rev for the RRE relative to antisense RNA was increased 100,000-fold. At molar ratios of Rev to RRE above 2, Rev dissociated from the RRE with a T1/2 of approximately 20-25 min.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Biochemical characterization of binding of multiple HIV-1 Rev monomeric proteins to the Rev responsive element. 839 95

An isocratic reversed-phase LC-MS method for measuring concentrations of 5-chloro-2',3'-dideoxy-3'-fluorouridine (935U83; I) directly and its 5'-glucuronide metabolite (5-chloro-2',3'-dideoxy-5'-O-beta-D-glucopyranuronosyl-3'-fluorour idine) indirectly in human plasma was developed, validated, and applied to a Phase I clinical study. The pyrimidine nucleoside, I, was extracted from human plasma by using anionic solid-phase extraction. The concentration of the glucuronide conjugate was determined from the difference between the molar concentration of I in a sample hydrolyzed with beta-glucuronidase and the nonhydrolyzed sample. Recovery of I from human plasma averaged 90%. The bias of the assay for I ranged from -5.5 to 7.1% during the validation and from -6.0 to 1.4% during application of the assay to the Phase I single-dose escalation study. The intra- and inter-day precision was less than 8% for I and its glucuronide conjugate. The lower and upper limits of quantitation for a 50-microliters sample were 4 ng/ml and 3000 ng/ml, respectively. No significant endogenous interferences were noted in human plasma obtained from drug-free volunteers nor from predose samples of HIV-infected patients.
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PMID:Validation of a high-performance liquid chromatographic-mass spectrometric method for the measurement of 5-chloro-2',3'-dideoxy-3' -fluorouridine (935U83) in human plasma. 897 6

Gingival crevicular fluid (GCF) levels of the polymorphonuclear leukocyte (PMN) lysosomal enzyme beta-glucuronidase (beta G), the pro-inflammatory cytokine interleukin 1 beta (IL-1 beta), and immunoglobulins (IgA, IgG, and IgM) were examined in 16 HIV seropositive (HIV+) and 10 HIV seronegative (HIV-) injecting drug users (IDU). Each subject received a periodontal examination including assessment of probing depth, attachment level, bleeding on probing, and plaque and calculus accumulation. GCF was collected from the mesial surfaces of premolar and molar teeth using filter paper strips. Although HIV+ subjects had a significantly lower number of peripheral blood CD4+ T cells/mm3 compared to HIV- subjects, there were no significant differences in mean probing depth, percentage of sites exhibiting bleeding on probing, or plaque and calculus accumulation between HIV- and HIV+ subjects. When the GCF components were analyzed, we found no significant differences between HIV- and HIV+ subjects in GCF levels of beta G, IL-1 beta, IgA or IgM, but GCF levels of IgG were significantly increased in HIV+ subjects. When sites were categorized by probing depth, no differences in the levels of beta G, IgA, IgG, and IgM existed between sites with probing depth < or = 3 mm compared to sites with probing depth > or = 4 mm in both HIV- and HIV+ IDU. However, levels of IL-1 beta in GCF were increased in the deeper sites (> or = 4 mm) in HIV+ IDU when compared to sites with PD < or = 3 mm. Analyzing GCF constituents in relation to the CD4 cell number, no differences were found between subjects with < or = 400 or > 400 CD4 cells/mm3 with respect to the levels of IL-1 beta, IgG, and IgM. However, the level beta G was significantly decreased in the HIV+ IDU with < or = 400 CD4 cells when compared to those with > 400 CD4 cells/mm3, while levels of IgA were significantly higher in HIV+ subjects with < or = 400 CD4 cells/mm3. Our results suggest that levels of IgG, and in immunodeficient subjects IgA were increased in GCF of HIV+ IDU while decreased levels of beta G were found in immunodeficient HIV+ IDU. These findings may be local manifestations of systemic alterations and suggest that analysis of GCF may provide insight into the immune and inflammatory responses of HIV-infected individuals to periodontal microorganisms.
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PMID:Inflammatory and immune mediators in crevicular fluid from HIV-infected injecting drug users. 910 Feb

A review of periodontal disease as a manifestation of HIV infection suggests a shift in emphasis over the past 5 years. Initially the focus was on newly described forms of periodontal disease (i.e., HIV-associated gingivitis or linear gingival erythema (LGE); HIV-associated periodontitis or necrotizing ulcerative periodontitis (NUP). While the clinical definition of LGE varies from study to study, an association between LGE and Candida infection has been described. Furthermore, the prevalence of NUP is quite low and this disorder is associated with severe immunosuppression. In contrast, the focus today is on the accelerated rate of chronic adult periodontitis occurring in seropositive patients. While the organisms that characterize adult periodontitis in seronegative individuals are present in subgingival plaque from seropositive individuals, reports suggest that atypical pathogens are also present (i.e., Mycoplasma salivarium, Enterobacter cloacae). Recent studies from our laboratory have identified a novel strain of Clostridium isolated from the subgingival plaque of injecting drug users that has pathologic potential. This organism, however, was found in both seropositive and seronegative individuals in this cohort, suggesting an association with lifestyle rather than serostatus. In addition, data has been published examining the local host response in periodontitis in seropositive individuals. Distinctly elevated levels of IgG in gingival crevicular fluid (GCF) have been observed in seropositive patients. Furthermore, data from our laboratory examining inflammatory mediators in GCF (polymorphonuclear leukocyte lysosomal enzyme beta-glucuronidase and the pro-inflammatory cytokine interleukin-1 beta) suggests an altered response in patients with HIV infection. The alteration manifests as the absence of the expected strong correlation between polymorphonuclear leukocyte activity in the gingival crevice and clinical measures of existing periodontal disease, as well as elevated levels of interleukin-1 beta in sites with deeper probing depths. Therefore, it can be concluded that the progression of periodontal disease in the presence of HIV infection is dependent upon the immunologic competency of the host as well as the local inflammatory response to typical and atypical subgingival microorganisms.
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PMID:Epidemiology and diagnosis of HIV-associated periodontal diseases. 945 78

Two HPLC methods were developed: one for the quantitation of HBY 097 reverse transcriptase inhibitor and its metabolites M2 and M3 in human serum, and one for the quantitation of metabolite M5 in urine. The HPLC procedure for the quantitation of HBY 097 and its metabolites M2 and M3 in human serum involved protein precipitation with acetonitrile followed by automated on-line trace enrichment. The HPLC procedure for the analysis of metabolite M5 in urine involved enzymatic hydrolysis of urine with beta-glucuronidase to convert metabolite M5 (glucuronide of M3) to M3. Reverse phase chromatographic separation with gradient elution. UV detection at 335 nm, and internal standard were used to quantitate analytes in both procedures. The lower quantitation limits were 25 ng ml-1 for HBY 097 and metabolites M2 and M3 in serum, and 0.5 microgram ml-1 for the metabolite M5 in urine measured as metabolite M3 after hydrolysis. The HBY 097 and metabolite M3 concentrations were specific but metabolite M2 was semi-specific because the two diastereomers of M2 were not resolved by the present chromatographic procedure. Both procedures were applied to the quantitation of HBY 097 and its metabolites in serum and urine of HIV positive patients who were enrolled in a clinical study of drug safety and pharmacokinetics.
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PMID:Quantitative analysis of HBY 097 and its metabolites in human serum and urine by HPLC. 957 37

Periodontal manifestations of human immunodeficiency virus (HIV) infection were first described in 1987. Initially, the lesions receiving attention were HIV-associated gingivitis (now known as linear gingival erythema [LGE]) and HIV-associated periodontitis (now known as necrotizing ulcerative periodontitis [NUP]). The true prevalence of LGE was difficult to determine due to variable diagnostic criteria. Recently, LGE has been associated with intraoral Candida infection. The prevalence of NUP is low (< or = 5%), and this lesion is associated with pronounced immunosuppression. Current focus on the periodontal manifestations of HIV infection centers on rapid progression of chronic adult periodontitis in HIV+ patients. Attempts to identify the pathogenesis of the increased progression of periodontitis have not proven successful. For example, analysis of subgingival plaque for the presence of bacterial pathogens has failed to detect differences between HIV+ and HIV- patients. Recently our laboratory has identified alterations in the host response in the gingival crevice of HIV+ patients. Comparing HIV+ and HIV- injecting drug users (IDU), levels of the proinflammatory cytokine interleukin-1 beta (IL-1 beta) in gingival crevicular fluid (GCF) were slightly elevated at sites with a probing depth of 1 to 3 mm. At deeper sites (> or = 4 mm), total IL-1 beta in GCF was significantly greater in HIV+ individuals. Using the lysosomal acid glycohydrolase beta-glucuronidase (beta G) as a measure of the influx of polymorphonuclear leukocytes (PMN) into the gingival crevice, our data indicated a significant correlation of total beta G in GCF and probing depth in the HIV-IDU (r = 76; P = .02). This result was similar to what we have observed in other studies. In contrast, for HIV+ subjects, total beta G was not associated with probing depth (r = .20; NS). These data suggest that HIV+ patients have altered regulation of PMN recruitment into the gingival crevice. We have begun to investigate the conditions under which subgingival Candida may contribute total periodontal lesions in HIV+ individuals. Candida from subgingival sites has been cultured in HIV+ individuals. Subgingival Candida was distinct from Candida isolated from tongue and buccal mucosal surfaces (as indicated by genomic fingerprinting). We hypothesize the absence of adequate priming of PMN by HIV+ patients. This may be due to a reduced Th1 lymphocyte response. The inability of HIV+ individuals to adequately prime PMN may allow Candida to colonize the subgingival environment. In that milieu, it may act directly or in concert with subgingival bacterial pathogens, or as a cofactor (by inducing production of proinflammatory cytokines) to increase the occurrence of periodontal attachment loss.
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PMID:New concepts regarding the pathogenesis of periodontal disease in HIV infection. 972 91


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