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)

Chromatographic separation of highly polar basic drugs with ideal ionspray mass spectrometry volatile mobile phases is a difficult challenge. A new quantification procedure was developed using hydrophilic interaction chromatography-mass spectrometry with turbo-ionspray ionization in the positive mode. After addition of deuterated internal standards and simple clean-up liquid extraction, the dried extracts were reconstituted in 500 microL pure acetonitrile and 5 microL was directly injected onto a Waters Atlantis HILIC 150- x 2.1-mm, 3-microm column. Chromatographic separations of cocaine, seven metabolites, and anhydroecgonine were obtained by linear gradient-elution with decreasing high concentrations of acetonitrile (80-56% in 18 min). This high proportion of organic solvent makes it easier to be coupled with MS. The eluent was buffered with 2 mM ammonium acetate at pH 4.5. Except for m-hydroxy-benzoylecgonine, the within-day and between-day precisions at 20, 100, and 500 ng/mL were below 7 and 19.1%, respectively. Accuracy was also below +/- 13.5% at all tested concentrations. The limit of quantification was 5 ng/mL (%Diff < 16.1, %RSD < 4.3) and the limit of detection below 0.5 ng/mL. This method was successfully applied to a fatal overdose. In Switzerland, cocaine abuse has dramatically increased in the last few years. A 45-year-old man, a known HIV-positive drug user, was found dead at home. According to relatives, cocaine was self-injected about 10 times during the evening before death. A low amount of cocaine (0.45 mg) was detected in the bloody fluid taken from a syringe discovered near the corpse. Besides injection marks, no significant lesions were detected during the forensic autopsy. Toxicological investigations showed high cocaine concentrations in all body fluids and tissues. The peripheral blood concentrations of cocaine, benzoylecgonine, and methylecgonine were 5.0, 10.4, and 4.1 mg/L, respectively. The brain concentrations of cocaine, benzoylecgonine, and methylecgonine were 21.2, 3.8, and 3.3 mg/kg, respectively. The highest concentrations of norcocaine (about 1 mg/L) were measured in bile and urine. Very high levels of cocaine were determined in hair (160 ng/mg), indicating chronic cocaine use. A low concentration of anhydroecgonine methylester was also found in urine (0.65 mg/L) suggesting recent cocaine inhalation. Therapeutic blood concentrations of fluoxetine (0.15 mg/L) and buprenorphine (0.1 microg/L) were also discovered. A relatively high concentration of Delta(9)-THC was measured both in peripheral blood (8.2 microg/L) and brain cortex (13.5 microg/kg), suggesting that the victim was under the influence of cannabis at the time of death. In addition, fluoxetine might have enhanced the toxic effects of cocaine because of its weak pro-arrhythmogenic properties. Likewise, combination of cannabinoids and cocaine might have increase detrimental cardiovascular effects. Altogether, these results indicate a lethal cocaine overdose with a minor contribution of fluoxetine and cannabinoids.
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PMID:A fatal overdose of cocaine associated with coingestion of marijuana, buprenorphine, and fluoxetine. Body fluid and tissue distribution of cocaine and its metabolites determined by hydrophilic interaction chromatography-mass spectrometry(HILIC-MS). 1551 97

Influenza virus infection can cause severe complications in human immunodeficiency virus type-1 (HIV-1)-infected individuals leading to an increased risk of complications and death compared to that seen in uninfected individuals. We assessed the capacity of influenza virus (Flu) to modulate transcription of the HIV-1 long terminal repeat (LTR) in human CD4+ T cells. We found that Flu is able to promote expression of both the transiently transfected and stably integrated HIV-1 LTR-driven reporter gene. Experiments performed with Arthrobacter-derived neuraminidase and ammonium chloride revealed that Flu-dependent activation of HIV-1 transcription required an intimate contact between Flu and the target cell and efficient entry of Flu inside human CD4+ T cells. Amplification of a Flu-specific mRNA by RT-PCR indicated that human T cells were indeed productively infected with Flu. Virus preparations rendered noninfectious after UV irradiation could no longer upregulate HIV-1 LTR activity. Furthermore, experiments conducted with wild type and NF-kappaB-mutated HIV-1 LTR-directed reporter vectors suggested that the positive action of Flu on HIV-1 LTR activity was mediated through the induction of NF-kappaB. Our data show that fully competent Flu can lead to NF-kappaB-dependent activation of HIV-1 transcription in CD4+ T cells.
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PMID:Influenza virus activates human immunodeficiency virus type-1 gene expression in human CD4-expressing T cells through an NF-kappaB-dependent pathway. 1563 53

We present a simple chromatographic method to detect and quantify protease inhibitors (PI), metabolites and non-nucleoside reverse transcriptase inhibitors (NNRTIs) in human plasma of HIV-1 infected patients and in peripheral blood mononuclear cells (PBMCs) using either liquid chromatography coupled with ultraviolet (LC-UV) or liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). A solid-liquid extraction was carried out on 500 microl of plasma as pre-treatment. Calibration curve ranges were from 50 (100) to 5000 ng/ml (indinavir). PBMC pellets from 7 ml of blood were lysed with methanol/tris with a calibration curve ranging from 0.25 to 250 ng/pellet. Simple modifications in the mobile phase composition (slight increase of ammonium acetate concentration and addition of methanol for LC-UV) easily linked the two analytical systems.
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PMID:Development of an assay method for the detection and quantification of protease and non-nucleoside reverse transcriptase inhibitors in plasma and in peripherical blood mononuclear cells by liquid chromatography coupled with ultraviolet or tandem mass spectrometry detection. 1579 20

A sensitive and accurate liquid chromatography-tandem mass spectrometric (LC-MS/MS) method for the intracellular determination of nine antiretroviral drugs in human peripheral blood mononuclear cells (PBMCs) is proposed. PBMCs are isolated by density gradient centrifugation using Vacutainer CPT tubes and cell count is performed with a Coulter instrument. Single-step extraction of drugs from PBMCs pellets is performed with MeOH 50% (with clozapine added as internal standard, I.S.) and the supernatant is injected onto a 2.1 mm x 30 mm SymmetryShield 3.5 microm-RP18 column equipped with a 2.1 x 10 mm guard column. Chromatographic separations are performed using a gradient program with a mixture of 2 mM ammonium acetate containing 0.1% formic acid and acetonitrile with 0.1% formic acid. Analytes quantification is performed by electro-spray ionisation-triple quadrupole mass spectrometry using the selected reaction monitoring (SRM) detection mode. The positive mode is used for the HIV protease inhibitors (PIs) indinavir, amprenavir, saquinavir, ritonavir, nelfinavir, lopinavir, atazanavir and the non-nucleoside reverse transcriptase inhibitors (NNRTIs) nevirapine, and the negative mode is applied for efavirenz. The calibration curves are prepared using blank PBMCs spiked with antiretroviral drugs at concentrations ranging from 0.5 to 100 ng/ml of cell extracts and fitted to a quadratic regression model weighted by 1/(concentration)(2). The lower limit of quantification is less than 0.5 ng/ml. The mean extraction recovery for all PIs/NNRTIs is always above 88%. The method is precise, with mean inter-day CV% within 0.6-10.2%, and accurate (range of inter-day deviation from nominal values -7.2 to +8.3%). This analytical method can be conveniently used in clinical research for the assessment of intracellular levels of all PIs/NNRTIs commercially available at present using a simple one-step cell extraction of PBMCs followed by liquid chromatography coupled with tandem triple quadripole mass detection.
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PMID:Intracellular measurements of anti-HIV drugs indinavir, amprenavir, saquinavir, ritonavir, nelfinavir, lopinavir, atazanavir, efavirenz and nevirapine in peripheral blood mononuclear cells by liquid chromatography coupled to tandem mass spectrometry. 1583 90

An HPLC-MS/MS assay for the determination of an HIV integrase inhibitor, 5-(1,1-dioxido-1,2-thiazinan-2-yl)-N-(4-fluorobenzyl)-8-hydroxy-1,6-naphthyridine-7-carboxamide (I) in human plasma has been developed and validated. Compound I and a stable isotope labeled internal standard (II) were isolated from 0.5 mL plasma samples by solid phase extraction using an Ansys SPEC C-8 96-well plate. Extracts were separated on a Hypersil BDS C-18 HPLC column (3.0 mmx50 mm, 3 microm) with a mobile phase consisting of 25 mM ammonium formate pH 3.0:acetonitrile (60:40) vol%/vol% pumped at 0.5 mL/min. A Sciex API 365 mass spectrometer equipped with an atmospheric pressure chemical ionization source was operated in selected reaction monitoring (SRM) mode with the precursor-to-product ion transitions m/z 431-->109 (I) and m/z 437-->115 (II) used for quantitation. The assay was validated over the concentration range of 10-5000 ng/mL and was found to have acceptable accuracy, precision, linearity, and selectivity. The mean extraction recovery from spiked plasma samples was 69%. The intra-day accuracy of the assay was within 4% of nominal and intra-day precision was better than 4% C.V. Following a 200 mg dose of the compound administered to human subjects, concentrations of I ranged from 21.1 to 1500 ng/mL in plasma samples collected up to 12 h after dosing. Inter-day accuracy and precision results for quality control samples run over a 3-month period alongside clinical samples showed mean accuracies of within 6% of nominal and precision better than 3.5% C.V.
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PMID:Determination of an investigational HIV integrase inhibitor in human plasma using high performance liquid chromatography with tandem mass spectrometric detection. 1586 94

Water and 80% ethanol extracts of 20 Thai medicinal plants used to treat AIDS were tested for their HIV type 1 reverse transcriptase inhibitory activity. The water extracts of Ipomoea carnea subsp. fistulosa (aerial parts), Vitex glabrata (branch), Vitex trifolia (aerial part), Vitex negundo (aerial part), Canna indica (rhizome), and Justicia gendarussa (aerial part) showed HIV-1 RT inhibition ratio (% IR) higher than 90% at a 200 microg/ml concentration. The water extract of Canna indica rhizomes (IC(50) 22.56 microg/ml) was selected for further study, i.e. for its HIV-1 RT inhibition activity and the purification and characterization of the active proteins. Proteins in water extract were fractionated by ammonium sulfate precipitation and separated by sodium dodecyl sulfate acrylamide gel electrophoresis (SDS-PAGE), yielding two proteins, Cip31 (31 kDa) and Cip14 (14 kDa) with IC50 of 17.41 and 19.25 microg/ml and isoelectric point (pI) of 3.5 and 6.35, respectively. Both proteins showed significant HIV-1 RT inhibition.
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PMID:In vitro HIV type 1 reverse transcriptase inhibitory activities of Thai medicinal plants and Canna indica L. rhizomes. 1595 Nov 45

A series of regioisomeric bis-fulleropyrrolidines bearing two ammonium groups have been synthesized and their activities against HIV-1 and HIV-2 have been evaluated. Two trans isomers have been endowed with interesting antiviral properties, confirming the importance of the relative positions of the substituent on the C(60) cage. In addition, reduced amphiphilicity of molecules to other compounds previously reported decreases their cytotoxicity in CEM cell cultures. None of the compounds showed any inhibitory activity against a variety of DNA and RNA viruses other than HIV.
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PMID:Anti-HIV properties of cationic fullerene derivatives. 1597 10

We identified a postentry restriction, termed Lv2, which determines the cellular tropism of two related human immunodeficiency virus type 2 (HIV-2) isolates and is dependent on the sequence of the capsid (CA) and envelope (Env) proteins. To explain the reliance on both CA and Env, we proposed that restrictive Envs deliver susceptible capsids to a compartment where Lv2 is active whereas nonrestrictive Envs deliver capsids into a compartment where Lv2 is either absent or less active. To test this model, we used compounds that affect endocytic pathways (ammonium chloride, bafilomycin A1, hypertonic sucrose) or lipid rafts (methyl-beta-cyclodextrin) to treat restrictive cells and show that restricted virus can be rescued from Lv2 if a lipid-raft-dependent, pH-independent endocytic pathway is inhibited. Furthermore, viral entry into HeLa/CD4 cells containing a tailless CD4 receptor, located outside lipid rafts, was fully permissive. Finally, we show that a variety of primary HIV-1 and HIV-2 viruses are susceptible to Lv2. Thus, we show that the route of entry, determined by the viral envelope, can influence cellular tropism by avoiding intracellular blocks to infection.
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PMID:An envelope-determined, pH-independent endocytic route of viral entry determines the susceptibility of human immunodeficiency virus type 1 (HIV-1) and HIV-2 to Lv2 restriction. 1601 4

Diffuse large B-cell lymphoma (DLBCL) is more prevalent and more often fatal in HIV-infected patients and SIV-infected monkeys compared to immune-competent individuals. Molecular, biological, and immunological data indicate that virus-associated lymphomagenesis is similar in both infected hosts. To find genes specifically overexpressed in HIV/SIV-associated and non-HIV/SIV-associated DLBCL we compared gene expression profiles of HIV/SIV-related and non-HIV-related lymphomas using subtractive hybridization and Northern blot analysis. Our experimental approach allowed us to detect two genes (a-myb and pub) upregulated solely in HIV/SIV-associated DLBCLs potentially involved in virus-specific lymphomagenesis in human and monkey. Downregulation of the pub gene was observed in all non-HIV-associated lymphomas investigated. In addition, we have found genes upregulated in both non-HIV- and HIV-associated lymphomas. Among those were genes both with known (set, ND4, SMG-1) and unknown functions. In summary, we have demonstrated that simultaneous transcriptional upregulation of at least two genes (a-myb and pub) was specific for AIDS-associated lymphomas.
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PMID:Differential gene expression in HIV/SIV-associated and spontaneous lymphomas. 1623 49

The UEV domain of the TSG101 protein functions in the vacuolar protein-sorting pathway and in the budding process of HIV-1 and other retroviruses by recognizing ubiquitin in proteins tagged for degradation and short sequences in viral proteins containing an essential and well conserved PTAP motif, respectively. A deep understanding of these interactions is key to the rational design of much-needed novel antivirals. Here, the crystal structure of the TSG101 UEV domain (TSG101-UEV) is presented. TSG101-UEV was crystallized in the presence of PEG 4000 and ammonium sulfate. Under these conditions, crystals were obtained in space group R3, with unit-cell parameters a = b = 97.9, c = 110.6 A, alpha = beta = 90, gamma = 120 degrees . Phases were solved by molecular replacement and the crystal structure of TSG101-UEV was refined to an R factor of 18.8% at 2.2 A resolution. A comparison between the crystal structure and previously reported NMR structures has revealed significant differences in the conformation of one of the loops implicated in ubiquitin recognition. Also, the resulting structure has provided information about the presence of water molecules at the binding interface that could be of relevance for peptide recognition.
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PMID:Structure of human TSG101 UEV domain. 1655 48


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