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)

Chemically induced hypothyroidism changes the functions of rat alveolar macrophages. Treatment of female rats with an anti-thyroid drug, methimazole (1% aqueous solution in drinking water for 6 weeks) significantly (p less than 0.05) reduced the ability of alveolar macrophages (MAM) to phagocytose and kill the yeast, Saccharomyces cerevisiae. Undigested yeasts were observed in phagolysosomes within MAM using transmission electron microscopy. The activities of the lysosomal enzymes, acid phosphatase and beta-glucuronidase, and the Fc receptor binding ability for immunoglobulin G, were lowered in MAM when compared with control macrophages (CAM). MAM also produced less tumor necrosis factor under the stimulation of lipopolysaccharide.
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PMID:Effect of methimazole-induced hypothyroidism on alveolar macrophages. 167 73

For the enantiospecific assay of propranolol in biological material, formation of diastereomeric derivatives is one possible approach. The aim of the present study was the development and optimization of three analytical methods based on different chiral reagents: phenylethylisocyanate and the acyl chloride as well as the isocyanate that are derived from the fluorescent S-flunoxaprofen. Pronethalol is used as internal standard in all three procedures and improves the coefficients of variation significantly. After extraction from human plasma or urine, propranolol is reacted with one of these compounds in anhydrous organic solvents with addition of triethylamine. The diastereomeric derivatives are then resolved on an octadecylsilane column using mixtures of water and methanol with or without addition of glacial acetic acid. Good resolutions of the diastereomeric derivatives are found under these conditions. Conjugates are cleaved prior to analysis using beta-glucuronidase-arylsulfatase and assayed as parent propranolol enantiomers. All three procedures were suitable for analysis of propranolol enantiomers in biological samples in the lower nanogram range (1-2 ng/mL). A preliminary clinical study confirmed the known enantiospecificity in the pharmacokinetics of propranolol and showed high concentrations of conjugates with R/S ratios that were similar to those of the parent enantiomers.
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PMID:Improved enantiospecific RP-HPLC assays for propranolol in plasma and urine with pronethalol as internal standard. 168 29

For the enantiospecific assay of propranolol in biological material, formation of diastereomeric derivatives is one possible approach. The aim of the present study was the development and optimization of three analytical methods based on different chiral reagents: phenylethylisocyanate and the acyl chloride as well as the isocyanate that are derived from the fluorescent S-flunoxaprofen. Pronethalol is used as internal standard in all three procedures and improves the coefficients of variation significantly. After extraction from human plasma or urine, propanolol is reacted with one of these compounds in anhydrous organic solvents with addition of triethylamine. The diastereomeric derivatives are then resolved on an octadecylsilane column using mixtures of water and methanol with or without addition of glacial acetic acid. Good resolutions of the diastereomeric derivatives are found under these conditions. Conjugates are cleaved prior to analysis using beta-glucuronidase-arylsulfatase and assayed as parent propranolol enantiomers. All three procedures were suitable for analysis of propranolol enantiomers in biological samples in the lower nanogram range (1-2 ng/mL). A preliminary clinical study confirmed the known enantiospecificity in the pharmacokinetics of propranolol and showed high concentrations of conjugates with R/S ratios that were similar to those of the parent enantiomers.
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PMID:Improved enantiospecific RP-HPLC assays for propranolol in plasma and urine with pronethalol as internal standard. 168 58

The activity patterns during development for acid phosphatase (Ac-P), alkaline phosphatase (A1-P), beta-glucuronidase (beta G), and UDP-glucuronyltransferase (UDPGT) have been determined in various tissues of the rat for corn oil and distilled water controls as well as in animals prenatally exposed to four fetotoxic chemicals. Postnatal assays were performed on both sexes separately. In control animals, tissue-specific differences between male and female activity levels were found for UDPGT. In the liver of mature offspring, enzyme activity was greater in males than in females. Although no sex difference was observed in the intestine, the kidneys of females exhibited higher values than those of males. An original computer-assisted methodology is presented, designed (a) to permit a mathematical description for the complex curves exhibited by these ontogeny profiles, and (b) to assess the statistical significance of chemical-induced alterations in these complex developmental patterns, specifically, to target sensitive periods and subtle changes near the fetotoxic threshold. Oral administration (days 6-18 of gestation) of 3,3',4,4'-tetrachlorobiphenyl (4CB) to pregnant females resulted in an induction of liver UDPGT activity in offspring postnatally, and some alterations in the perinatal pattern of beta G in the same tissue. This treatment also produced differences in the intestinal patterns of Ac-P and male UDPGT. No significant changes were observed in offspring exposed to diethylstilbestrol (DES). Treatment with zeranol (ZN) caused reductions in activity over the entire postnatal period for beta G in liver, brain, intestine, and kidney, for A1-P in brain, and for Ac-P in the intestine. Cadmium-treated dams gave birth to offspring that exhibited slightly altered ontogenies only in intestine for UDPGT and AcP. The alterations in these developmental profiles indicate periods of increased sensitivity, and may be useful in directing more specific studies into the fetotoxic mechanisms of these compounds.
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PMID:Fetotoxic alterations in the normal ontogenies of rat microsomal and lysosomal enzymes. 177 May 2

A rapid and sensitive method for extracting temazepam from human serum and urine is presented. Free temazepam is extracted from plasma and urine samples using n-butyl chloride with nitrazepam as the internal standard. Temazepam glucuronide is analyzed as free temazepam after incubating extracts with beta-glucuronidase. Separation is achieved using a C8 reversed-phase column with a methanol-water-phosphate buffer mobile phase. An ultraviolet detector operated at 230 nm is used and a linear response is observed from 20 ng/ml to 10 micrograms/ml. The limit of detection is 15.5 ng/ml and the limit of quantitation is 46.5 ng/ml. Coefficients of variation are less than 10% for concentrations greater than 50 ng/ml. Application of the methodology is demonstrated in a pharmacokinetic study using eight healthy male subjects.
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PMID:Determination of temazepam and temazepam glucuronide by reversed-phase high-performance liquid chromatography. 178 47

The new United States Drinking Water Regulations state that water systems must analyze for Escherichia coli or fecal coliforms on any routine or repeat sample that is positive for total coliforms. The proposed methods for the detection of E. coli are based on beta-glucuronidase activity, using the fluorogenic substrate 4-methylumbelliferyl beta-D-glucuronide (MUG). This study was conducted to determine whether beta-glucuronidase negative E. coli were present in significant numbers in environmental waters. Two hundred and forty E. coli cultures were isolated from 12 water samples collected from different environmental sources. beta-glucuronidase activity was determined using lauryl tryptose broth with MUG, EC broth with MUG, and the Autoanalysis Colilert (AC) procedure. The isolates were also evaluated by the standard EC broth gas fermentation method for fecal coliforms. The results confirm that assaying for the enzyme beta-glucuronidase utilizing the MUG substrate is an accurate method for the detection of E. coli in environmental waters.
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PMID:Evaluation of beta-glucuronidase assay for the detection of Escherichia coli from environmental waters. 180 10

A medium containing the fluorogenic substrate 4-methylumbelliferyl-beta-D-glucuronide was developed for the isolation and identification of Escherichia coli within 7.5 h and was based on the detection of beta-glucuronidase. Optimum conditions for the rapid development of fluorescent colonies were determined. The optimum temperature was 41.5 degrees C. Development of fluorescence was delayed when carbohydrates were incorporated into the medium. Water samples were used to evaluate the medium by surface plating and membrane filtration. The frequency of false-negative results was 6.1% and false-positives were 3.7% for freshwater samples. The false-positive organisms were identified as Klebsiella spp. and Shigella sonnei. The potential applications of the medium are discussed.
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PMID:A rapid fluorogenic method for the detection of Escherichia coli by the production of beta-glucuronidase. 187 84

The present study examines the structure of the lysosomal system of mature oocytes in mussels, Mytilus galloprovincialis, after a 21 day exposure to the water accommodated fraction (WAF) of two crude oils (types Ural and Maya) and of a commercial lubricant oil. The automated image analysis indicates that lysosomes, showing cytochemically demonstrable beta-glucuronidase activity, are smaller and much more numerous in oocytes of mussels treated with a 40% dose of Ural- and Lubricant-WAF when compared to controls. It is suggested that the structure of the lysosomal system of oocytes is different from that of somatic cells (i.e., digestive cells) and that budding or "fission" into smaller bodies occurs in oocyte lysosomes under certain petroleum hydrocarbon-exposure conditions. These changes in the lysosomal compartment appear to be associated to the process of gamete release or spawning.
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PMID:Automated measurement of lysosomal structure alterations in oocytes of mussels exposed to petroleum hydrocarbons. 195 29

1. Orally administered 3H-benzo[a]pyrene (3H-BaP) was excreted in the bile of White Suckers predominantly as water soluble metabolites some of which were hydrolyzed by arylsulfatase or beta-glucuronidase. 2. Non-hydrolysible polar metabolites comprised a substantial proportion of biliary metabolites. 3. HPLC analysis revealed fluorescent and 3H-labelled peaks which co-eluted with standards of the glucuronide and sulfate conjugates of BaP. 4. The most polar peak co-chromatographed with a double-radiolabelled metabolite produced in vitro with 3H-BaP and 35S-glutathione. 5. Inhibition of epoxide hydrolase in vitro reduced all water soluble metabolites except the glutathione conjugate of BaP. 6. Glutathione conjugation represents a major hepatic detoxication pathway of BaP in White Suckers.
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PMID:The role of glutathione S-transferases in the hepatic metabolism of benzo[a]pyrene in white suckers (Catostomus commersoni) from polluted and reference sites in the Great Lakes. 197 53

Recently, Escherichia species other than Escherichia coli have been isolated from potable water. Environmental isolates as well as clinical isolates of E. adecarboxylata, E. blattae, E. fergusonii, E. hermannii, and E. vulneris were assayed for the enzyme beta-glucuronidase by using EC MUG medium and the Colilert system. None of the isolates were positive for the enzyme by either method.
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PMID:Assay for beta-glucuronidase in species of the genus Escherichia and its applications for drinking-water analysis. 201 93


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