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Grases F - - 1994
OBJECTIVE: To study the initial steps of calcium oxalate monohydrate (COM) stone formation and the influence of the inhibitor substances citrate and phytic acid, using an in vitro model. MATERIALS AND METHODS: Experiments were performed using a device to simulate renal stone formation in conditions similar to those found in ...
Tomigahara Y - - 1994
1. Two major metabolites of 14C-labelled (4S,1R)-trans-Etoc[(S)-2-methyl-4-oxo-3-(2-propynyl)cyclopent-2-enyl (1R)-trans-chrysanthemate] were purified using a combination of chromatographic techniques and identified by spectroanalysis (nmr(HMBC) and FAB-, TSP-MS). These were established as new types of S-linked conjugates (sulphonic acid and mercapturic acid types). 2. To examine the mechanism of formation of the sulphonic acid ...
Urban G - - 1994
1. Chlorofluorohydrocarbons are presently being developed as alternatives for ozone-depleting chlorofluorocarbons. 1,1-Dichloro-2,2,2-trifluoro-[2-14C]-ethane (HCFC-123) is a chlorofluorohydrocarbon with potential widespread use and associated human exposure. As a part of the toxicological evaluation of HCFC-123, its metabolism was studied in rodents in a closed recirculating exposure system. 2. Two male rats were ...
Dugelay S - - 1994
Phenylacetate, derived from phenylalanine, is converted in human and primate liver to phenylacetylglutamine. The latter, which is excreted in urine, has been used to probe noninvasively the labeling pattern of liver citric acid cycle intermediates. We present nuclear magnetic resonance assays for the urinary concentration of phenylacetylglutamine and for the ...
Arano Y - - 1994
In pursuit of radiolabeled monoclonal antibodies (mAbs) with rapid urinary excretion of radioactivity from nontarget tissues, radioiodinated mAbs releasing a m-iodohippuric acid from the mAbs in nontarget tissues were designed. A novel reagent, maleimidoethyl 3-(tri-n-butylstannyl)hippurate (MIH), was synthesized by reacting N-(hydroxyethyl)maleimide with N-Boc-glycine before coupling with N-succinimidyl 3-(tri-n-butylstannyl)benzoate (ATE). MIH ...
Mashige F - - 1994
An HPLC system for the simultaneous determination of acidic catecholamine metabolites, related compounds and 5-hydroxyindoleacetic acid (5-HIAA) in human urine was developed. A mixed-mode (C18/anion-exchange) column with isocratic elution using citrate buffer and an eight-channel electrochemical detector were used. Vanilmandelic acid (VMA), 3,4-dihydroxyphenylacetic acid (DOPAC), 4-hydroxy-3-methoxyphenyllactic acid (vanillactic acid, VLA), ...
Yamaguchi T - - 1994
Seven bilirubin metabolites negative to the diazo reaction were identified in the urine of healthy persons by enzyme-linked immunosorbent assay (ELISA) using the anti-bilirubin monoclonal antibody 24G7. Two of the seven metabolites were isolated and their chemical structures were determined using fast-atom bombardment-mass spectroscopy (FAB-MS) and 1H-NMR. The two metabolites ...
Hui J - - 1994
Digoxin (D3) metabolism is partially mediated by the gastrointestinal tract via acid hydrolysis of digitoxose sugar moieties and bacterial reduction of the lactone. The hypothesis that hypochlorhydria influences digoxin disposition was tested in six normochlorhydric (NC) and four hypochlorhydric (HC) subjects. D3 tablets were administered daily for 19 to 28 ...
Kestell P - - 1994
1. Xanthenone-4-acetic acid (XAA) is an experimental antitumour agent which resembles flavone-8-acetic acid in its induction of cytokine synthesis, nitric oxide production and tumour haemorrhagic necrosis. We have investigated the excretion and metabolic fate of XAA in the BDF1 mouse. 2. XAA was administered intravenously at the maximal tolerated dose ...
Rodopoulos N - - 1994
Caffeine (CA) and its 14 main metabolites were determined in urine by reversed-phase high-performance liquid chromatography (RP-HPLC) and capillary electrophoresis (CE). After addition of 1,3,9-trimethylxanthine, uracil and beta-hydroxyethyltheophylline as internal standards, samples were separated by RP-HPLC into three fractions; A, B and C. The fractions were concentrated by lyophilization and ...
Cravedi J P - - 1994
Following subcutaneous administration of [3H]chloramphenicol (CP) to duck, HPLC and TLC analyses showed that the two most important metabolites in 0- to 24-hr excreta were CP-oxamic acid and CP-alcohol, which together accounted for about one-third of the radioactivity therein. The remainder was due to unchanged CP (15% dose), CP-base (5% ...
Sugahara K - - 1994
Liquid chromatography-atmospheric pressure chemical-ionization mass spectrometry (LC-APCI-MS) was used for the analysis of N-acetylamino acids that could not be determined with an amino acid analyzer. LC-APCI-MS could directly detect the protonated molecular ions of various synthetic N-acetylamino acids, distinguishing N-acetylserine from O-acetylserine and N(alpha)-acetyllysine from N(epsilon)- acetyllysine. Furthermore, N-acetylasparagine, N-acetylaspartic ...
Buchet J P - - 1994
A study was undertaken to assess whether the consumption of fish and shellfish containing a high concentration (> 1500 micrograms/kg) of organoarsenical compounds was associated with the release of a significant amount of inorganic arsenic (Asi) in vivo. Volunteers were given a known quantity of seafood (ray, cod, plaice, mussel) ...
Yoshioka K - - 1994
A sensitive and specific method was developed for measuring medium-chain dicarboxylic acids (adipic and suberic acid) in urine. These acids were extracted from urine with diethyl ether and converted into fluorescent derivatives with 9-anthryldiazomethane, which can be separated by high-performance liquid chromatography. The reproducibility was high and the recovery from ...
Van Dam J J - - 1994
A survey was conducted to check the toxicological impact of ethylene glycol present in a thermal decomposition mixture of type C hydraulic fluid on laboratory animals submitted to an inhalation test. The target organs, i.e. kidneys, of exposed rats were evaluated histologically and oxalic acid--the ethylene glycol metabolite thought to ...
Kataoka H - - 1994
A selective and sensitive method has been developed for the determination of sulphur amino acids by gas chromatography (GC). Sulphur amino acids were converted into their N(S)-isopropoxycarbonyl methyl ester derivatives and measured by GC with flame photometric detection using a DB-17 capillary column. The derivatives were sufficiently volatile and stable ...
Hippenstiel M J - - 1994
The maximum stability conditions for cocaine and its metabolite benzoylecgonine (BE) in urine were analyzed. Suggestions were presented after careful review of many studies and personal communications concerning cocaine and BE stability in urine. The optimal storage conditions for urine specimens with cocaine and BE were determined to be at ...
Seiler N - - 1994
Orotic acid was separated from other urinary constituents by ion-pair formation with tetrabutylammonium, and isocratic elution from a reversed-phase column. Absorbance at 280 nm was recorded for quantitation. Owing to the better column characteristics the separations are somewhat faster, and the sensitivity of the method is higher than those of ...
Vree T B TB Department of Clinical Pharmacy, Academic Hospital Nijmegen Sint Radboud, - - 1994
A gradient reversed-phase HPLC analysis for the direct measurement of salicylic acid (SA) with the corresponding glycine and glucuronide conjugates in plasma and urine of humans was developed. The glucuronides were isolated by preparative HPLC from human urine samples. The concentration of the glucuronides in the isolated fraction were determined ...
Horiuchi K - - 1994
A substance that exhibited a tryptophan-like fluorescence peak at 354 nm on excitation at 295 nm at neutral pH was isolated from human urine. This compound was determined by visible-light absorption spectroscopy, fluorescence spectroscopy, 1H and 13C NMR spectroscopies, and FAB-MS to be 1-(1',2',3',4',5'-pentahydroxypentyl)-1,2,3,4-tetrahydro-2-carboli ne-3- carboxylic acid. This compound, named ...
Kinuta M - - 1994
S-[2-Carboxy-1-(1H-imidazol-4-yl)ethyl]-3-thiolactic acid (CIE-TL), a novel imidazole compound with a sulphur-containing side chain, was isolated from normal human urine by ion-exchange column chromatography, and characterized by physicochemical analyses involving m.s., i.r. spectrophotometry, high-voltage paper electrophoresis and elemental analysis as well as chemical synthesis. CIE-TL was synthesized by the reaction of S-[2-carboxy-1-(1H-imidazol-4-yl)ethyl]cysteine ...
Atmani F - - 1994
We recently reported that human urine contains a newly identified urinary glycoprotein acting as a potent inhibitor against calcium oxalate crystallization. This inhibitor is a uronic-acid-rich protein (UAP) with a molecular weight of approximately 35 kDa. In the present study, UAP was isolated from urine of stone formers and of ...
Oreste P - - 1994
GAGs were purified from urine of dogs after intranasal administration of 40 mg/kg ITF 1300. The electrophoretic patterns of urine GAGs in acidic buffer showed the presence of heparin together with chondroitins, heparan sulfate, and hyaluronic acid. The heparin present in urines was purified using chondroitinase ABC, and its purity ...
Kawabata S - - 1994
Five metabolites were detected in the plasma and urine of a patient following ingestion of the organophosphate insecticide, phenthoate. Intact phenthoate was detected only in gastric lavage fluid. After methylation of acidic extracts of plasma and urine, phenthoate acid, demethyl phenthoate, demethyl phenthoate oxon acid, demethyl phenthoate S-isomer, and demethyl ...
Kaur M - - 1994
We screened 2560 referred cases for inborn errors of amino acid metabolism by chemical tests and thin-layer chromatography of urine/plasma. In 62(2.4%) cases, eleven inherited Mendelian disorders of amino acids were identified. The four commonest disorders were homocystinuria, alcaptonuria, maple syrup urine disease and nonketotic hyperglycinaemia. Ornithinaemia was detected in ...
Inoue H - - 1994
The metabolites of clentiazem in the urine or bile of rats and dogs were investigated. Fifteen basic, 6 acidic, 2 neutral and 4 conjugated metabolites were isolated. In the present paper, fourteen reference compounds as shown in Charts 1, 2 and 3 were synthesized to identify the structures of the ...
Linhart I - - 1994
1-Butylacrylate, an industrial monomer, is rapidly metabolized by carboxylesterase-catalyzed hydrolysis to acrylic acid and 1-butanol. Acrylic acid enters the intermediary metabolism and is efficiently degraded to carbon dioxide as the metabolic end product. To obtain a virtually complete metabolic pattern, rats were dosed by a single intraperitoneal dose of 1 ...
Huang M Y - - 1994
The urinary excretion of hippuric acid and methylhippuric acid was studied in workers (233 subjects; 122 men and 111 women) exposed to toluene and xylenes in combination and in non-exposed controls (281 subjects; 141 men and 140 women) recruited from the same factories or factories of the same regions. Smoking ...
Duran M - - 1994
Selective screening for inherited metabolic disorders can be performed efficiently by chromatographic techniques. Each technique is suited for a well-defined group of substances present in urine, plasma and CSF. A comprehensive screening programme may involve the analysis of amino acids, organic acids, imidazoles, purines and pyrimidines, oligosaccharides and mucopolysaccharides in ...
Sakai T - - 1994
For the gaschromatographic determination of total butoxyacetic acid (BAA), i.e., free plus conjugated BAA in urine, we studied the acid hydrolysis condition to cleave the conjugate. The optimum condition for hydrolysis was chosen to be 60 min boiling of the mixture of 1 ml twofold diluted urine and 1.2 ml ...
Lee K J - - 1994
The factors affecting micellar electrokinetic capillary chromatographic separation of hippuric and o-, m-, p-methylhippuric acid were investigated by changing the species of micelles, and adding urea to the micellar solution. The analysis of hippurates in human urine is demonstrated under optimum conditions using 20 mM phosphate buffer (pH 8.0) containing ...
Popp W - - 1994
Different parameters of biological monitoring were applied to 26 benzene-exposed car mechanics. Twenty car mechanics worked in a work environment with probably high benzene exposures (exposed workers); six car mechanics primarily involved in work organization were classified as non-exposed. The maximum air benzene concentration at the work places of exposed ...
Burns S P - - 1993
Argininosuccinate (ASA) is excreted in large amounts in the urine of patients with argininosuccinate lyase (EC 4.3.2.1) deficiency (ASLD). Previous workers have reported the presence of anhydrides of ASA in the urine of patients with this disorder. We have used 1H-NMR spectroscopy to investigate the presence of these compounds in ...
Zezulak M - - 1993
Analysis of the opiates, morphine and codeine, often proceeds by way of acid hydrolysis for release of the parent morphine from its glucuronide formed during metabolism. Following use, heroin is rapidly deacetylated to 6-monoacetylmorphine (6-MAM), which can be detected in the urine for a short time following injection of heroin. ...
Schäfer F F Institute of Occupational and Social Medicine, University of Ulm, - - 1993
This paper describes a procedure for the identification of phenylmercapturic acid in urine of benzene-exposed mice. Collected urine of benzene exposed mice was adjusted to pH 7 and applied to an anion exchanger. After extraction with diethyl ether and evaporation to dryness, the sample was dissolved in aqueous phosphoric acid ...
Bechtold W E - - 1993
Three biomarkers for benzene exposure were developed. The first biomarker, muconic acid in urine, results from the ring opening of a benzene metabolite. A gas chromatography/mass spectroscopy (GC/MS) assay was developed to measure urinary muconic acid, and the analyte in urine samples from workers occupationally exposed to benzene was determined. ...
Paul B D - - 1993
Benzoylecgonine, 11-nor-delta 9-tetrahydrocannabinol-9-carboxylic acid (THC-acid), phencyclidine, codeine, morphine, amphetamine, methamphetamine, and lysergic acid diethylamide were dissolved in urine, stored frozen in plastic tubes at -16 to -18 degrees C, defrosted, transferred to other tubes, and analyzed by gas chromatography/mass spectrometry (GC/MS); no significant loss of compound was observed, except for ...
Armstrong D W - - 1993
Recently it was found that normal adults excrete pipecolic acid primarily as the D-enantiomer even though it is present in the blood stream mainly as the L-enantiomer (i.e. > 98% L). This study of pipecolic acid stereochemistry was extended to subjects with peroxisomal deficiencies since they are known to have ...
Okada T - - 1993
Novel cystathionine mono-oxo acids, S-(3-oxo-3-carboxy-n-propyl) cysteine and S-(2-oxo-2-carboxyethyl) homocysteine, and cyclic amino acid, cystathionine ketimine, have been detected in the urine of a patient with cystathioninuria using liquid chromatography-mass spectrometry with an atmospheric pressure ionization interface system and an amino acid analyzer. To determine these cystathionine mono-oxo acids and cystathionine ...
Ghauri F Y - - 1993
The urine of rats fed on 1% paracetamol in the diet for up to 10 weeks was analysed using 500 MHz 1H NMR spectroscopy. After 3 weeks, paracetamol-dosed rats were found to excrete massive quantities of an unknown metabolite in the urine. Using a range of 1 and 2 dimensional ...
Loftus N J - - 1993
The metabolism and pharmacokinetics of [2H10]di-2-(ethylhexyl) adipate (DEHA) labelled on the ethyl side-chains was determined in six male volunteers. The dose administered was 46 mg [2H10]DEHA given orally. No parent molecule was found in plasma; however, the metabolite [2H5]2-ethylhexanoic acid (EHA) was detected (mean rate of formation: 1.63 +/- 1.19/hr; ...
Johnson E H - - 1993
An eight year old wild caught Cynomolgus monkey was diagnosed as having alkaptonuria, a condition characterized by the passage of a normal-colored urine which darkens upon standing. The underlying cause is the congenital lack of homogentisic acid oxidase with subsequent passage of homogentisic acid in the urine. No other clinical ...
Kataoka H - - 1993
A selective and sensitive method has been developed for the analysis of free and bound forms of O-phosphoamino acids, such as O-phosphoserine, O-phosphothreonine and O-phosphotyrosine, in urine samples by gas chromatography (GC). For free O-phosphoamino acid analysis, the urine sample was extracted with trichloroacetic acid and run through an ion ...
Nakamura S - - 1993
Following oral dosing of [14C]clentiazem to rats the metabolites in urine and bile were separated and their chemical structures were investigated by HPLC and GC-MS analyses. Fifteen basic, 6 acidic, 2 neutral and 4 conjugated metabolites were found in urine and/or bile. Eight basic metabolites (MB1-8) were identified as the ...
Kok D J - - 1993
Using urine samples and standard solutions, this study demonstrates that the existing procedure for measuring titratable acidity in the urine is not reliable and may result in overestimates of up to 25%. The accuracy is affected by loss of CO2, the presence of uric acid crystals, and the precipitation of ...
Takeda N - - 1993
1. Tyrosine and tryptophan, as well as 26 metabolites of these amino acids, were analyzed simultaneously in urine specimens from patients with neuroblastoma and control infants by a three-dimensional HPLC system to develop an early diagnosis. 2. Levels of detected compounds in urine from patients with neuroblastoma were generally higher ...
Houghton I T - - 1993
219 surgical patients of either Caucasian, Chinese or Nepalese origin were given pethidine 1 mg/kg by intramuscular injection as pre-operative medication. Urine was collected for 24 h and analysed for pethidine, pethidinic acid, pethidinic acid conjugates, norpethidine, norpethidinic acid, and norpethidinic acid conjugates. The mean proportion of the percentage of ...
Vree T B - - 1993
A gradient reversed-phase high pressure liquid chromatographic analysis was developed for the direct measurement of nalidixic acid with its acyl glucuronide, 7-hydroxymethylnalidixic acid with its acyl and ether glucuronides, and 7-carboxynalidixic acid in human plasma and urine. The glucuronides and 7-carboxynalidixic acid were not present in plasma after an oral ...
Yoshino H - - 1993
1. Several metabolites of 14C-labelled N-[4-chloro-2-fluoro-5-[(1-methyl- 2-propynyl)oxy]phenyl]-3,4,5,6-tetra-hydrophthalimide (S-23121) were identified. 2. The major urinary metabolites were found to be 4-chloro-2-fluoro-5-hydroxyaniline, its sulphate and glucuronide by t.l.c. cochromatography with authentic standards. 3. The major faecal metabolites in addition to the parent compound were six sulphonic acid conjugates having a sulphonic acid ...
Knapp F F FF - - 1993
To measure pancreatic lipase activity, we synthesized a triglyceride containing a radioiodinated fatty acid. The urinary excretion of radioactivity was measured in five rats following administration of the agent by feeding tube. We attached 15-phenylpentadecanoic acid (PPA) to position-3 of 1,2-dipalmitoyl-rac-glycerol (1,2-Pal) to form 1,2-Pal-3-PPA. The 1,2-Pal-3-IPPA (expected lipase substrate) ...
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