Search Results
Results 601 - 650 of 1393
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de Zwart L L - - 1996
1. 4-Hydroxy-2,3-nonenal (HNE) is an end product of lipid peroxidation (LPO) and a well known cytotoxic aldehyde that exhibits a variety of biological effects. In this study the in vivo disposition and covalent binding of i.p. administered [2-3H]HNE was examined in the rat. 2. It was found that several metabolites ...
Norman R W - - 1996
Twenty-four-hour urine collections are an important part of the metabolic evaluation of stone-formers, but are difficult for patients at work. At weekends the results might be different. Forty-five stone-formers who worked at day jobs from Monday to Friday collected urine for 24 h on a normal working day and also ...
Bort R - - 1996
Aceclofenac ([2-(2',6'-dichlorophenylamino)phenyl]acetoxyacetic acid) is a novel nonsteroidal antiinflammatory drug, the pharmacokinetics and drug metabolism of which show species differences. After oral administration to the rat, circulating aceclofenac rapidly disappears yielding [2-(2',6'-dichlorophenylamino)phenyl]acetic acid (diclofenac), which is then further oxidized to [2-(2',6'-dichloro-4'-hydroxyphenylamino)phenyl[acetic acid (4'-hydroxydiclofenac) and [2-(2',6'-dichloro-4'-hydroxyphenylamino)phenyl]acetic acid (4'-hydroxydiclofenac) and [2-(2',6'-dichlorophenylamino)-5-hydroxyphenyl]acetic acid (5-hydroxydiclofenac). ...
Christensen J J - - 1996
Recently, some Aerococcus-like organisms (ALOs), isolated from urine and blood of elderly patients with urinary tract infection, have been described. In this study ALOs and related taxons were tested for susceptibility by agar diffusion and agar dilution methods to 15 selected antimicrobial agents for diagnostic and taxonomic considerations. ALOs were ...
Bort R - - 1996
Metabolism of the new nonsteroidal antiinflammatory drug aceclofenac ([2-(2',6'-dichlorophenylamino)phenyl]acetoxyacetic acid) was investigated both in the in vitro hepatic human models and in vivo. Aceclofenac is metabolized in human hepatocytes and human microsomes to form [2-(2',6'-dichloro-4'-hydroxy- phenylamino)phenyl]acetoxyacetic acid as the major metabolite, which is then further conjugated. Minor metabolites were [2-(2',6'-dichlorophenylamino)-5-hydroxyphenyl]acetoxyacetic ...
Meng L J - - 1996
A series of pregnanediols and pregnanetriols doubly conjugated with N-acetylglucosamine and glucuronic or sulfuric acid has been identified in urine from pregnant women. Steroid conjugates were separated by ion-exchange chromatography and the glucuronide and monosulfate fractions were analysed by fast atom bombardment mass spectrometry. After removal of the acid moiety, ...
al-Harbi M M - - 1996
Camel urine treatment was found to cause a significant cytotoxic effect in the bone marrow cells of mice. This cytotoxicity at higher doses was comparable with that of standard drug cyclophosphamide (CP). However, unlike CP, the camel urine treatment failed to induce any clastogenicity. The cytotoxicity induced by camel urine ...
Bartges J W - - 1996
OBJECTIVE: To evaluate the effects of dilution and alkalinization, separately and together, on the stability of uric acid in canine urine stored at -20 C. DESIGN: Prospective-controlled study. ANIMALS: 5 dogs with confirmed ammonium urate uroliths, 6 Beagles, and 6 mixed-breed dogs. PROCEDURE: Dogs were fed a 31.4% protein (dry ...
Costa C C - - 1996
Three new metabolites of medium-chain fatty acid oxidation, 3-, 6- and 7-hydroxyoctanoyl beta-D-glucuronide, were identified in the urine of six infants who were fed a diet enriched in medium-chain triglycerides (MCT). Glucuronides were extracted from the urine by organic solvent extraction with ethyl acetate and by solid-phase extraction on Sep-Pak ...
Spracklin D K - - 1996
The volatile anesthetic sevoflurane is degraded to fluoromethyl 2,2-difluoro-1-(trifluoromethyl)vinyl ether (FDVE), a potent rat nephrotoxin. In rats in vivo, FDVE undergoes glutathione conjugation and metabolism to cysteine conjugates, whose bioactivation by renal cysteine conjugate beta-lyase has been implicated by the protective effects of (aminooxy)acetic acid, an inhibitor of cysteine conjugate ...
Henry C J - - 1996
Urine cortisol:creatinine ratios (UCCR) were determined from single urine samples obtained by cystocentesis in 47 cats allotted into 2 groups: 31 healthy cats and 16 sick, hospitalized cats with assorted clinical illnesses. The mean (+/- standard deviation) UCCR for healthy cats was 5.9 +/- 7.0 (median, 3.2; range, 0.6 to ...
Ong C N - - 1996
OBJECTIVE: To carry out a comprehensive field investigation to evaluate various conventional and recently developed biomarkers for exposure to low concentrations of benzene. METHODS: Analyses were carried out on environmental air, unmetabolised benzene in blood and urine, urinary trans, transmuconic acid, and three major phenolic metabolites of benzene: phenol, catechol, ...
Navarro M - - 1996
A procedure has been developed for determination of total selenium in urine by hydride generation atomic absorption spectrometry. Mineralization was performed with a nitric acid-perchloric acid mixture on a thermostated digestion block. The method was validated by comparison with the method involving mineralization in a microwave acid digestion bomb containing ...
Poon G K - - 1996
Limonene is a farnesyl transferase inhibitor that has shown antitumor properties. The drug had been given orally to cancer patients. Plasma and urine samples collected from the patients were examined by reversed-phase HPLC-atmospheric pressure chemical ionization and electrospray ionization MS. The drug underwent rapid conversion to hydroxylated and carboxylated derivatives. ...
Alemany G - - 1996
A TLC method for the simultaneous analysis of vanillylmandelic, homovanillic and 5-hydroxyindole-3-acetic acids in urine is described. The sample is cleaned up through a cyano minicolumn and extracted with diethyl ether. The acids are resolved by high-performance TLC, visualized by Folin Ciocalteau reagent and quantificated by densitometry at 600 nm ...
Carducci C - - 1996
An automatic and sensitive HPLC method for the determination of primary and secondary amino acids included cystine and homocystine in urine samples is described. After a simple ultrafiltration, urine samples were subjected to reduction of disulfides, carboxymethylation of free thiols and double precolumn derivatization with o-phthalaldehyde-3-mercaptopropionic acid and 9-fluroenylmethyl chloroformate. ...
Pulgarin J A - - 1996
A new method for the determination of nalidixic acid in urine is proposed for concentrations between 25 and 1000 ng ml(-1) by means of matrix isopotential synchronous fluorescence spectrometry. This new technique is useful for the determination of compounds in samples with unknown background fluorescence, such as nalidixic acid in ...
WroĊ„ski M - - 1996
The essential steps in the assay included electrolytic reduction of disulphides, neutralization, extraction of thiols with 0.1 M tributyltin hydroxide in octane, stripping of the extract with 2% acetic acid, fixing the washed-out amino thiols to a cation exchanger, elution with 2 M hydrochloric acid, oxidation with bromine and evaporation. ...
Tserng K Y - - 1996
Increased amounts of dicarboxylic acids are excreted in human urine under conditions of medium-chain triglyceride (MCT) feeding, abnormal fatty acid oxidation (FAO) and fasting. Criteria to distinguish dicarboxylic aciduria originating from MCT feeding and other conditions are needed in urinary organic acid profiling for detecting inborn errors of metabolism. Patterns ...
Bernauer U - - 1996
Chronic bioassays with trichloroethene (TRI) demonstrated carcinogenicity in mice (hepatocellular carcinomas) and rats (renal tubular cell adenomas and carcinomas). The chronic toxicity and carcinogenicity is due to bioactivation reactions. TRI is metabolized by cytochrome P450 and by conjugation with glutathione. Glutathione conjugation results in S-(dichlorovinyl) glutathione (DCVG) and is presumed ...
Asami M - - 1996
CS-670, a novel nonsteroidal anti-inflammatory drug, is a racemic prodrug. Plasma concentrations and urinary excretion of CS-670 and its metabolites were determined in experimental subjects after oral administration at a single 120 mg dose. CS-670 and four metabolites, the saturated ketone (M-A), unsaturated-alcohol (M-B), cis-alcohol (M-C), and trans-alcohol (M-D), were ...
Hallson P C - - 1996
The ability of three compounds, all similar in chemical structure to citric acid, to decrease calcium crystalluria has been measured. The measurements were made in normal human urine at 37 degrees C and compared with the crystal-decreasing power of citric acid when measured in the same way and in the ...
Valkonen S - - 1996
The scheme consists of analyses for phenol,2,5-hexanedione, and mandelic, trichloroacetic and methylhippuric acids in urine. The present participants are 31 laboratories from 14 countries. Samples are prepared by pooling urine obtained from occupationally exposed workers or by spiking with appropriate pure metabolites. Four sets of samples at two concentration levels ...
Pelclová D - - 1996
Oxidative phenotype P-450 2D6 was examined using sparteine test in 3 groups of persons to determine if there is a coincidence in the defect of the oxidative biotransformation of sparteine and impaired oxidation of toluene, which could explain interindividual differences in the amounts of hippuric acid in the urine in ...
Tuomainen A - - 1996
This study examined the possibility of using biological monitoring to assess deltamethrin exposure among greenhouse workers. The synthetic pyrethroid deltamethrin was sprayed in five greenhouses by cold for generators, and the exposure was biologically monitored by analysing the concentration of its metabolite, 3-phenoxybenzoic acid, by a gas chromato-graphic method after ...
Mori M A - - 1996
1. Conjugates of 2,4-dinitrobenzyl alcohol (2,4-DNB) and 2,6-dinitrobenzyl alcohol (2,6-DNB), which were major urinary metabolites of the male Wistar rat dosed orally with 2,4-dinitrotoluene (2,4-DNT) or 2,6-dinitrotoluene (2,6-DNT), were examined by hplc using potassium 2,4-dinitrobenzyl glucuronide (2,4-DNB-G), potassium 2,6-dinitrobenzyl glucuronide (2,6-DNB-G), pyridinium 2,4-dinitrobenzyl sulphate (2,4-DNB-S), and pyridinium 2,6-dinitrobenzyl sulphate (2,6-DNB-S) ...
Yin H - - 1996
1,2-Dichloro-1-fluoroethane (HCFC-141) and 1,1,2-trichloro-2-fluoroethane (HCFC-131) were chosen as models to study the regioselectivity of halogenated alkane metabolism. Metabolites in the urine of rats given HCFC-131 ip were the following: inorganic fluoride, chlorofluoroacetic acid, dichloroacetic acid, N-(2-hydroxyethyl)chlorofluoroacetamide, and three unidentified minor metabolites. In vitro incubation of HCFC-131 with either rat liver ...
Arthur K - - 1995
A gas chromatographic-mass spectrometric method is described for the assay of propionic acid and of isovaleric acid in physiological fluids by isotope dilution. The acids are derivatized to the pentafluorobenzyl esters to decrease volatility to render them suitable for GC-MS analysis. The following reference values were found. Propionic acid: plasma ...
Pietta P G - - 1995
An extract of Ginkgo biloba leaves (EGb) was administered by gastric probe to Wistar female rats, and urine and faeces samples were collected for 5 days and whole blood samples were withdrawn every 30 min for 6 h. After purification with SPE C18 cartridges, the samples were analysed by reversed-phase ...
el Sawalhy A - - 1995
Trypanosoma brucei gambiense, which causes human African trypanosomiasis, catabolizes the aromatic amino acid tryptophan via an initial aminotransferase catalyzed reaction to form several indole end products, which have been suggested to contribute to the pathogenesis of trypanosomiasis. To determine if this same pathway exists in T. evansi, the closely related ...
Petras T - - 1995
The cytotoxic lipid peroxidation product 4-hydroxynonenal (HNE) was infused into rat kidney. During the first 2 min a rapid degradation of a 100 microM HNE solution was demonstrated. After 5 min the consumption rate of 4-HNE reached a steady state of about 75 nmoles/ml. The total HNE consumption rate was ...
Taylor W G - - 1995
In rats treated ip with N-ethylbenzamide (EB) at doses of 250-500 mg/kg, this amide was metabolized by hydrolysis to ethylamine and benzoic acid, the latter detected in the urine as hippuric acid. Proposed metabolic pathways were investigated by treatment of male Wistar rats with EB and N-ethyl-alpha-13C-benzamide followed by examination ...
De La Peña A M - - 1995
A method is described for the simultaneous determination of the main urinary acetylsalicylic acid (aspirin) metabolites, salicyclic, salicyluric and gentisic acids, based on their native fluorescence. The urine was extracted into diethyl ether in acid medium, and back-extracted with glycine/sodium hydroxide buffer solution at pH 9.4. A comparative study of ...
Ruenitz P C - - 1995
The nonsteroidal antiestrogen tamoxifen (TAM) is subject to extensive biotransformation in humans and laboratory animals. In particular, the dimethylamino group of TAM undergoes N-demethylation and formal replacement with a hydroxyl group, affording major metabolites TAM amine and TAM alcohol, respectively. In the present study in ovariectomized rats, TAM was eliminated ...
Elia M - - 1995
Five healthy male subjects were continuously infused subcutaneously with [14C]bicarbonate (12.3 microCi/day) using a mini pump for 5 days while in a whole body calorimeter. Energy expenditure was varied over a range of 1.35-1.75 times basal metabolic rate. Urine collections were obtained throughout the study and used to measure the ...
Yang J M - - 1995
The sulphoxidation metabolites of moricizine, moricizine sulphoxide (M-sulphoxide) and moricizine sulphone (M-sulphone) were isolated and identified in the rat bile and urine and in human plasma and urine following administration of moricizine hydrochloride. The sulphoxide and sulphone were synthesized chemically by peroxidation of moricizine hydrochloride with hydrogen peroxide at 25 ...
Kostrewski P - - 1995
The possibility of evaluating occupational exposure to mesitylene based on the determination of unchanged solvent in capillary blood or 3,5-dimethylbenzoic acid in urine was investigated. The volunteers were exposed to mesitylene in a toxicological chamber (range 10-150 mg/m3). Concentrations of solvent or its metabolite in biological material were determined by ...
Diss E - - 1995
Methylmalonic aciduria is a rare metabolic disorder of amino acid metabolism that is characterized by accumulation of large amounts of methylmalonic acid in the blood and urine. To our knowledge this is the first case report of a patient with methylmalonic aciduria who carried a pregnancy to term; the outcome ...
Yin H - - 1995
1-Fluoro-1,1,2-trichloroethane (HCFC-131a), 1,2-dichloro-1,1-difluoroethane (HCFC-132b), and 1,1,1-trifluoro-2-chloroethane (HCFC-133a) were chosen as models for comparative metabolism studies on 1,1,1,2-tetrahaloethanes, which are under consideration as replacements for ozone-depleting chlorofluorocarbons (CFCs). Male Fischer 344 rats were given 10 mmol/kg ip HCFC-131a or HCFC-132b or exposed by inhalation to 1% HCFC-133a for 2 h. Urine ...
Atmani F - - 1995
Human urine contains several macromolecules which inhibit calcium oxalate crystallization. Uronic-acid-rich protein (UAP), a glycoprotein with a molecular weight of approximately 35 kDa, is one such inhibitor. Here we report the characterization of UAP extracted from rat urine using three chromatographic steps including diethylaminoethanol (DEAE)-Sephacel, Sephacryl S-300 and Mono Q ...
Alary J - - 1995
4-Hydroxy-2-nonenal (HNE), an aldehyde end product of lipid peroxidation in biological systems, is capable of producing a range of powerful biological effects. Despite its biological relevance, the metabolic fate of this aldehyde is unknown in vivo. This study examines the urinary excretion of HNE in the rat and the nature ...
Machida Y - - 1995
Novel cystathionine metabolites, perhydro-1,4-thiazepine-3,5-dicarboxylic acid (PHTZDC), cystathionine mono-oxo acids [S-(3-oxo-3-carboxy-n-propyl)cysteine and S-(2-oxo-2-carboxyethyl)homocysteine], cystathionine ketimines, cystathionine sulfoxide and N-acetylcystathionine sulfoxide were identified previously in the urine of patients with cystathioninuria. We have identified these compounds for the first time in the urine of D,L-propargylglycine-treated rats using LC/APCl-MS (liquid chromatography-mass spectrometry with ...
Elfarra A A - - 1995
Butadiene monoxide (BM), a mutagen and carcinogen, is the major metabolite of 1,3-butadiene in rats and mice. Because mercapturic acids (N-acetyl-L-cysteine S-conjugates) were expected in vivo metabolites of BM, reference BM-mercapturic acids were prepared by the reaction of racemic BM with N-acetyl-L-cysteine. Four isomers were purified and characterized as diastereomeric ...
Hallier E - - 1995
Urine samples from 20 male workers in the polyester industry exposed by inhalation to styrene concentrations ranging from 29 to 41 ppm were investigated. Excretion products of styrene metabolism, mandelic acid and mercapturic acids, were purified from the urine over an extraction column packed with Porapak Q, with subsequent ether ...
Van Offel J F JF Dienst Immunologie, Allergie en Reumatologie, Universitair Ziekenhuis Antwerpen, - - 1995
Ochronosis is a rare disease caused by an inherited lack of homogentisic acid oxidase. Alkaptonuria is the presence of homogentisic acid in urine. Ochronosis is characterized by the deposition of a dark pigment in tissues rich in collagen. A wide spectrum of clinical manifestations is described. The most important signs ...
Monté S Y - - 1994
In this work, oxidative metabolism of the new propellant, 1,1,1,2-tetrafluoroethane to trifluoroacetic acid in man is shown to be minimal. Alternative propellants and refrigerants are under development to replace the currently used chlorofluorocarbons which lead to stratospheric ozone depletion. One potentially useful replacement is the hydrofluorocarbon, 1,1,1,2-tetrafluoroethane (HFA-134a). Before it ...
Rossi R - - 1994
Reference values for tubular transport of sodium, phosphate, glucose and amino acids are generally based on inulin or creatinine short-term clearances, which are difficult to obtain in children. Hence, quantitative assessment of tubular transport capacities is rarely performed. For a simplified procedure, reference values for fractional sodium excretion, phosphate reabsorption ...
Matsumoto T - - 1994
4-Isopropenyltoluene (8) was administered orally to rabbits and the following four optically active metabolites, 2-(p-tolyl)propanoic acid (10), p-(1-carboxyethyl)benzoic acid (11), 2-hydroxy-2-(p-tolyl)propanoic acid (12), and 2-(p-tolyl)-1,2-propanediol (13) were isolated from urine in addition to an optically inactive metabolite, 4-isopropenylbenzoic acid (9). The enantiomeric ratios of the metabolites 10 and 11 were ...
van Rooyen J P - - 1994
The identity of two formerly novel citric acid analogues, homocitric acid and methylhomocitric acid, in urine samples from patients with propionic acidaemia was confirmed by gas chromatography and mass spectrometry. Authentic reference substances were synthesized using a Reformatskii reaction. Homocitric acid and methylhomocitric acid were detected as minor metabolites in ...
Turesky R J - - 1994
Heterocyclic aromatic amines (HAAs) are animal carcinogens and suspected human carcinogens which are formed in cooked foods at the low parts per billion level. HAAs in cooked meats were purified by either immunoaffinity chromatography or solid phase tandem extraction, which allowed for the simultaneous analysis of 11 HAAs by HPLC. ...
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