Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.2.1.31 (beta-glucuronidase)
7,680 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To study the disposition kinetics of methamphetamine (MAP), we have developed a sensitive high-performance liquid chromatographic (HPLC) assay to quantitate the enantiomers of MAP and its major metabolites, amphetamine (AP), p-hydroxymethamphetamine (p-OH-MAP), and p-hydroxyamphetamine (p-OH-AP), the latter two of which are hydroxylated metabolites, in rat urine. To determine conjugated hydroxylated metabolites, urine samples were treated with beta-glucuronidase. Both hydrolyzed and nonhydrolyzed p-OH-MAP and p-OH-AP were extracted into ethyl acetate and back extracted with 0.05M HCl. To determine MAP and AP, urine samples were extracted with benzene, followed by back extraction into 0.05M HCl. The acid layer was collected, and to it was added (-)-1-(9-fluorenyl)ethyl chloroformate (FLEC) for the derivatization of MAP and its metabolites. Derivatization was allowed to proceed for 24 h at room temperature. The derivatized products were separated on a C18 column with a mobile phase consisting of acetate buffer (pH 3.6)-acetonitrile-tetrahydrofuran. Quantitation was achieved using a fluorescence detector at an excitation wavelength of 265 nm and an emission wavelength of 330 nm. Linear standard curves were obtained over the concentration range of 5-100 ng/mL. The interday and intraday coefficients of variation for the assay for all eight enantiomers at 10 and 75 ng/mL were less than 13%. The detection limit was 5 ng/mL or 0.5 ng on-column.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Separation and quantitation of the enantiomers of methamphetamine and its metabolites in urine by HPLC: precolumn derivatization and fluorescence detection. 756 90

The possibility of minimizing organ damage following cardiopulmonary bypass (CPB) was examined. In the control group, n = 21, upon completion of CPB, elevation of the lysosomal enzyme beta-glucuronidase, which is a sensitive indicator of cellular damage, was affected by the concentration of granulocyte elastase (r = 0.59) or the endothelial-derived constricting factor, endothelin, (r = 0.8). Renal damage, which was detected by an increase in renal tubular enzymes (N-acetyl-beta-D-glucosaminidase and gamma-glutamyltranspeptidase) in urine, was also affected by endothelin (r = 0.79, r = 0.56), elastase (r = 0.6, r = 0.71), and by free hemoglobin levels (r = 0.76, r = 0.82). Next, the efficacy of pharmacological intervention for the prevention of renal damage was evaluated. During CPB, the administration of an elastase inhibitor (ulinastatin, 3 x 10(5) IU), n = 8, or a calcium antagonist (nicaldipine HCl, elastase release inhibitor; 5 gamma/kg per min), n = 8, significantly reduced the elevation of beta-glucuronidase and renal tubular enzymes (p < 0.05). Although the ulinastatin and nicardipine groups demonstrated low values of elastase in the Intensive Care Unit (ICU), only the values of the nicardipine group reached statistical significance (p < 0.05). A reduction in endothelin levels compared to the control group was observed in the nicardipine group. However, preventive and counteractive effects of nicardipine against vasoconstriction caused by endothelin were also considered to play an important role in the prevention of renal damage. The addition of haptoglobin (4,000 IU) to the priming solution of the CPB also reduced levels of renal tubular enzymes (p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Pharmacological intervention for renal protection during cardiopulmonary bypass. 830

This assay method allows a simultaneous determination of imipramine, desipramine, their 2-hydroxylated metabolites, and imipramine-N-oxide in 0.5 ml of plasma or 0.1 ml of urine within 35 min by an ion-paired, reversed phase (C18) high-performance liquid chromatography (HPLC) with electrochemical detection. The analytes are extracted from alkalinized plasma or urine with 5 ml of a 90/10 mixture (by vol) of diethyl either/2-propanol, back-extracted into 0.5 ml of 0.1 mol/L phosphoric acid. Urine samples are enzymatically treated with beta-glucuronidase/arylsulfatase before extraction. The electrochemical detection is performed with a glassy carbon electrode set at +0.85 V against the Ag/AgCl reference electrode. Recoveries for the analytes and the internal standard (propericiazine) from plasma or urine ranged from 66.4 to 105.7% with coefficients of variation (CVs) of < 6.8%. The intra- and interassay CVs for the analytes were < 17.4% in plasma and < 14.2% in urine. The limits of determination (a signal-to-noise ratio of 3) for imipramine, desipramine, 2-hydroxyimipramine, 2-hydroxydesipramine, and imipramine-N-oxide were 0.5, 0.3, 0.02, 0.02, and 1.0 microgram/L, respectively. Only four of the 23 psychotropic drugs, which might be coadministered with imipramine or desipramine, were considered to be the possible sources to interfere with the assay. We evaluated clinical applicability of this method by determining plasma concentration- and urinary excretion-time courses of the respective analytes in an extensive and a poor metabolizer of the debrisoquine/sparteine-type oxidation after a single oral dose of imipramine HCl (25 mg). The present method appears to be suitable not only for the therapeutic drug monitoring of imipramine and its active metabolites but also for studying the pharmacogenetically related metabolism of imipramine or desipramine.
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PMID:Simultaneous high-performance liquid chromatography-electrochemical detection determination of imipramine, desipramine, their 2-hydroxylated metabolites, and imipramine N-oxide in human plasma and urine: preliminary application to oxidation pharmacogenetics. 833 3

Consumption of fossil fuels has increased indoor and outdoor concentrations of polycyclic aromatic hydrocarbons (PAHs) and nitrogen dioxide (NO2). To study the combined effect of PAH administration and NO2 exposure on mutagenicity of urine from animals we injected 400 mg/kg body wt i.p. one of five kinds of PAH (pyrene, fluoranthene, fluorene, anthracene and chrysene) into ICR mice, Wistar rats, Syrian golden hamsters or Hartley guinea pigs after exposure to 20 p.p.m. NO2 gas for 24 h and then exposed the animals to NO2 gas for an additional 24 h. During the latter 24 h we collected the urine and assayed its mutagenicity with the Ames Salmonella strains after treatment with beta-glucuronidase and arylsulfatase and extraction with dichloromethane. The urine from mice treated with both PAH and NO2 showed high mutagenicity for Salmonella typhimurium strains TA98 and TA100, whereas the urine from mice treated with PAH and air showed almost no mutagenic activity. The mutagenicity was decreased in nitroreductase- and acetyltransferase-deficient strains TA98NR and TA98/1,8-DNP6 respectively. Treatment with a mixture of 20% of each of the five kinds of PAH and NO2 augmented the urinary mutagenicity of mice 1.5-fold. The urine from hamsters treated with pyrene or fluoranthene and NO2 was also highly mutagenic, but that from rats or guinea pigs was not very mutagenic. The mutagenicity was also decreased in strains TA98NR and TA98/1,8-DNP6. These results suggest that the urine contains nitro compounds and that the nitration of PAHs occurs in the body of animals under exposure to NO2 gas. Actually, the nitrated metabolites of pyrene, 1-nitro-6/8-hydroxypyrene and 1-nitro-3-hydroxypyrene, were detected in the urine from mice treated with pyrene under exposure to NO2 gas. To elucidate the mechanism of in vivo nitration, NO2 (20 p.p.m.) was bubbled through 50 mM Tris-HCl buffer (pH 7.4) or dichloromethane solution containing pyrene or 1-hydroxypyrene (10 microg/ml). Pyrene was not nitrated by NO2 in either aqueous or organic solutions. However, 1-hydroxypyrene was changed to nitrohydroxypyrenes by NO2 in the Tris-HCl buffer, but not in the organic solution. Ascorbic acid, alpha-tocopherol, glutathione oleic acid and hemoglobin were found to inhibit the nitration of 1-hydroxypyrene in aqueous solution. The urinary mutagenicity of mice treated with both pyrene and NO2 was also decreased by oral administration of ascorbic acid and alpha-tocopherol. These results suggest that 1-hydroxypyrene is nitrated by an ionic reaction in the animal body after hydroxylation of pyrene in the liver.
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PMID:In vivo formation of mutagens by intraperitoneal administration of polycyclic aromatic hydrocarbons in animals during exposure to nitrogen dioxide. 870 53

Testing human hair for drugs of abuse is a relatively new technique which requires control before being fully accepted in justice applications. Laboratories must be able to demonstrate that they can accurately determine what drugs are present in unknown hair samples and at what levels. To date few exercises have been organized in USA, Germany and France, all devoted to opiates, cocaine and cannabis. However, the number of drugs which can be detected in hair is growing every day. Among them, amphetamine and related compounds, such as MDMA, are of major interest due to increasing abuse. At the initial state of this work, four different preparation procedures were used to test amphetamine, MDA and MDMA. Direct methanol extraction, acid (HCl 0.1 N), alkaline (NaOH 1 N) and enzymatic (beta-glucuronidase/arylsulfatase) hydrolyses were compared. Best recoveries were observed after alkaline hydrolysis. The same hair sample was powdered and sent to 16 laboratories, in USA (4), Germany (6), France (3), Spain (1), Japan (1) and Korea (1) to test amphetamine, methamphetamine, MDA and MDMA. All laboratories returned results within 3 months. Amphetamine tested positive 13 times with concentrations ranging from 3.3 to 17.5 ng/mg. Only 2 laboratories identified methamphetamine, using GC/MS, at low concentration (0.8 and 1.8 ng/mg), which appears to be a false positive. MDA and MDMA both tested positive in 14 cases, with concentrations ranging from 1.8 to 19.5, and 8.9 to 100.0 ng/mg for MDA and MDMA, respectively. These scattered results clearly indicated that new exercises are needed to ensure quality in hair testing. This is one of the major aims of the Society of Hair Testing.
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PMID:Interlaboratory comparison of quantitative determination of amphetamine and related compounds in hair samples. 904 20

In this study, a very reliable HPLC method was developed for the determination of fenofibric acid and reduced fenofibric acid in the biological samples described as follows. After addition of the internal standard solution and 0.5 M HCl to the biological sample, fenofibric acid, reduced fenofibric acid and the internal standard were extracted with a mixed solvent of n-hexane and ethyl acetate (90:10) from the mixture. The acids were back-extracted from the organic phase with 0.1 M Na2HPO4 and then re-extracted from the aqueous phase with a mixed solution of n-hexane and ethyl acetate (95:5) after addition of 0.5 M HCl. The organic phase was evaporated to dryness under the vacuum. The residue was dissolved in MeOH and diluted with distilled water. An aliquot of the resulting solution was injected on the HPLC. High reproducibility was observed in this HPLC method (C.V.% less than 4%). Moreover it was confirmed that the conjugates in the urine could be hydrolyzed by incubation at 37 degrees C for 18 h after addition of 400 IU of beta-glucuronidase.
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PMID:[High-performance liquid chromatographic method for the determination of fenofibric acid and reduced fenofibric acid in human blood, plasma and urine]. 980 May 17

Residues of 19-nortestosterone (19-NT) and diethylstilboestrol (DES) are excreted in bovine urine, mainly conjugated to glucuronic acid. Prior to quantification, urine must be deconjugated, which is commonly performed by enzymatic or chemical hydrolysis. The efficiencies of two enzymatic and two chemical deconjugation methods were studied. The range of efficiencies obtained for DES were 51.8% (beta-glucuronidase, incubation at 37 degrees C overnight) and 2.7% (methanolic HCl), respectively. Similarly, efficiencies for NT ranged from 43.1% (beta-glucuronidase, incubation at 55 degrees C for 2 h) to 12.7% (methanolic HCl). The results highlight that within control laboratories significant underestimation of drug residue content in samples may occur, due to poor deconjugation.
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PMID:Comparison of the efficiences of enzymatic and chemical hydrolysis of (nortestosterone and diethylstilboestrol) glucuronides in bovine urine. 1141 66

From the roots of the Chinese medicinal herb Pseudostellaria heterophylla a single-chained lectin with a molecular weight of 36 kDa and high hemagglutinating activity was isolated. The lectin was adsorbed on DEAE-cellulose in 10 mM Tris-HCI buffer (pH 7.4) and was eluted by the same buffer containing 50 mM NaCl. It was adsorbed on SP-Sepharose in 10mM NH4OAc (pH 4.5) and eluted by approximately 0.5 M NaCl in the same buffer. The hemagglutinating activity of the lectin could not be inhibited by a large variety of monosaccharides, but was largely abrogated by exposure to 0.05 M HCl, 0.05M NaOH or 80 degrees C. However, about 50% of the activity remained after exposure to 0.025M NaOH or 40 degrees C. Despite possession of an N-terminal sequence exhibiting some similarity to thaumatin-like proteins with antifungal activity, the lectin was devoid of antifungal activity. The lectin exerted some inhibitory effect on the glycohydrolases alpha-glucosidase, beta-glucosidase and beta-glucuronidase which are involved in HIV infection but had no suppressive action on human immunodeficiency virus-type 1 reverse transcriptase.
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PMID:A novel lectin from Pseudostellaria heterophylla roots with sequence simularity to Kunitz-type soybean trypsin inhibitor. 1144 23

Quality assurance data show that there is very significant inter-laboratory variation of the quantitation of codeine, especially in patient samples. The authors have examined hydrolysis procedures for codeine glucuronide (C6G) and morphine-3- and -6-glucuronides (M3G, M6G) because these are often present together in urine samples. Comparisons of hydrolysis using two different sources of beta-glucuronidases and various concentrations of hydrochloric acid were made. Samples were concentrated using solid phase extraction, derivatized and quantified by selective ion monitoring using gas chromatography-mass spectrometry (GC-MS). and beta-glucuronidase efficiently hydrolyzed M3G (90-95%), while hydrolysis of M6G was lower (60-85%) and that of C6G was very poor (45-58%). These findings were confirmed on examination of urine samples containing codeine and morphine from subjects who had taken codeine, morphine, or heroin. Erratic inter-laboratory quality assurance results for codeine are most probably a result of incomplete C6G hydrolysis. The authors' optimized hydrolysis method using 50% HCl for 1.5 hours at 120 degrees C gave reproducible results that approached the spiked concentration.
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PMID:Optimizing the hydrolysis of codeine and morphine glucuronides in urine. 1235 38

Rubber tree (Hevea brasiliensis Muell. Arg.) is an important industrial crop for natural rubber production. At present, more than 9.5 million hectares in about 40 countries are devoted to rubber tree cultivation with a production about 6.5 million tons of dry rubber each year. The world supply of natural rubber is barely keeping up with a global demand for 12 million tons of natural rubber in 2020. Tapping panel dryness (TPD) is a complex physiological syndrome widely found in rubber tree plantations, which causes severe yield and crop losses in natural rubber producing countries. Currently, there is no effective prevention or treatment for this serious malady. As it is a perennial tree crop, the integration of specific desired traits through conventional breeding is both time-consuming and labour-intensive. Genetic transformation with conventional breeding is certainly a more promising tool for incorporation of agronomically important genes that could improve existing Hevea genotype. This chapter provides an Agrobacterium-mediated transformation protocol for rubber tree using immature anther-derived calli as initial explants. We have applied this protocol to generate genetically engineered plants from a high yielding Indian clone RRII 105 of Hevea brasiliensis (Hb). Calli were co-cultured with Agrobacterium tumefaciens harboring a plasmid vector containing the Hb superoxide dismutase (SOD) gene and the reporter gene used was beta-glucuronidase (GUS) gene (uidA). The selectable marker gene used was neomycin phosphotransferase (nptII) and kanamycin was used as selection agent. We found that a suitable transformation protocol for Hevea consists of a 3-d co-cultivation with Agrobacterium in the presence of 20 mM acetosyringone, 15 mM betaine HCl, and 11.55 mM proline followed by selection on medium containing 300 mg/L kanamycin. Transformed calli surviving on medium containing 300 mg/L kanamycin showed a strong GUS-positive reaction. Upon subsequent subculture into fresh media, we obtained somatic embryogenesis and germinated plantlets, which were found to be GUS positive. The integration of uidA, nptII, and HbSOD transgenes into Hevea genome was confirmed by polymerase chain reaction (PCR) as well as Southern blot analysis.
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PMID:Rubber Tree (Hevea brasiliensis Muell. Arg). 1703 60


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