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Wanders R J - - 1988
The ability of human liver to oxidize L-pipecolic acid was investigated. Liver from control subjects was found to contain L-pipecolic acid oxidase, an H2O2-producing enzyme not previously demonstrated in mammals. In livers from patients with the cerebro-hepato-renal syndrome of Zellweger, a genetic disease characterized by the absence of morphologically distinguishable ...
Zimmerman B J - - 1988
Allopurinol has been shown to provide significant protection against ischemia/reperfusion-induced microvascular and parenchymal cell injury. It has been hypothesized that the protection seen with allopurinol after ischemia/reperfusion (I/R) is caused by inhibition of xanthine oxidase. However, recent reports suggest that the beneficial effects of allopurinol in I/R may be caused ...
Venkateswarlu Y - - 1988
Scorpion (Buthus tamulus) venom was subjected to neutralization by treating the venom with various chemicals such as hydrochloric acid, sodium hydroxide, thiourea, formaldehyde, zinc sulphate, acetic acid and trichloroacetic acid. The venom was also subjected to heat treatment. The levels of total protein, free amino acids and protease activity in ...
Schreiner C L - - 1988
In previous studies we have found that porcine kidney fibroblasts will grow in medium containing D-2-hydroxy-4-methylthiobutanoic acid (D-methionine hydroxy analogue, D-MHA) as the sole source of methionine but not in medium containing the L-isomer (L-MHA) alone. The fibroblasts have been found to have both D-2-hydroxy acid dehydrogenase (EC 1.1.99.6), which ...
Konno R - - 1988
A simple and rapid method to screen for mutant mice (Mus musculus) lacking D-amino-acid oxidase activity has been devised. Mice were given water containing small amounts (0.02%) of either D-methionine or D-phenylalanine. Urinary levels of the D-amino acid were examined using thin-layer chromatography. Some mice excreted substantial amounts of the ...
Hoshi M - - 1988
Mouse embryos at the 1-cell stage were cultured in various concentrations of mycophenolic acid and xanthine. Mycophenolic acid at 10 and 2.5 micrograms/ml completely inhibited development to the morula and blastocyst stages, respectively. The addition of xanthine reversed the inhibitory effects of mycophenolic acid on the embryos but the reversal ...
Gale G R - - 1988
Administration of caffeine (CAF) to mice as early as 6 hr prior to injection of a hepatotoxic but nonlethal dose of acetaminophen (ACM) significantly antagonized the hepatotoxic action of ACM as judged by serum levels of alanine aminotransferase (ALT) activity. Administration of CAF after ACM produced complete antagonism only when ...
Silverman R B - - 1988
Mechanism-based enzyme inactivator, alanine racemase, S-adenosylhomocysteine hydrolase, D-amino acid aminotransferase, gamma-aminobutyric acid aminotransferase, arginine decarboxylase, aromatase, L-aromatic amino acid decarboxylase, dihydrofolate reductase, dihydroorotate dehydrogenase DNA polymerase I, dopamine beta-hydroxylase, histidine decarboxylase, beta-lactamase, monoamine oxidase, ornithine decarboxylase, serine proteases, testosterone 5 alpha-reductase, thymidylate synthetase, xanthine oxidase.
Frandsen J C - - 1988
1. Radiolabeled epinephrine, norepinephrine, octopamine and histamine were introduced into homogenates of mixed sexes of the nematode Trichostrongylus colubriformis and the labeled derivatives formed during incubation were identified by HPLC. Vanillylmandelic acid (VMA), 4-hydroxy-3-methoxyphenyl glycol (HMPG) and metanephrine were formed from epinephrine. 2. VMA, HMPG and normetanephrine were produced from ...
Nagata Y - - 1988
1. Two simple, rapid and sensitive methods are described for measurement of D-amino acid oxidase (DAO) activity using crude tissue extracts for the study of distribution patterns. 2. They detect products of oxidative deamination of D-amino acids catalyzed by DAO, i.e. alpha-keto acids and H2O2 by measuring light absorbances at ...
Bacher M A - - 1988
Induction of the cytochrome P-450 mixed-function oxidase and specifically the cytochrome P-450 IVA1 isoenzyme by seven phenoxyacid herbicides in rat liver have been studied. Liver microsomes from rats orally treated with the herbicides at 3 dose levels showed a significant increase in total cytochrome P-450 content with 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) ...
Liesivuori J - - 1987
Adult male rabbits were injected i.v. with 100 mg buffered formic acid per kg body weight daily for 5 days with 24 h between the doses. The fifth dose was labelled with 14C-formic acid. Rabbits were killed 1, 2 and 20 h after the last injection. The highest formic acid ...
Vamecq J - - 1987
Peroxisomal fatty acyl-CoA oxidase was inhibited by micromolar concentrations of antimycin A, an inhibitor of mitochondrial respiration. The inhibition was observed with all three substrates tested, i.e. palmitoyl-CoA, trihydroxycoprostanoyl-CoA and hexadecanedioyl-CoA. The peroxisomal D-amino acid oxidase was also inhibited by antimycin, but the peroxisomal L-alpha-hydroxyacid oxidase and uric acid oxidase ...
Juorio A V - - 1987
The addition of L-3,4-dihydroxyphenylalanine, L-5-hydroxytryptophan or m-tyrosine to cultured isolated astrocytes does not elicit the synthesis of either dopamine, 5-hydroxytryptamine or m-tyramine, respectively. In contrast, the astrocytes show ability to take up and store dopamine and 5-hydroxytryptamine that are in turn respectively metabolized to 3,4-dihydroxyphenylacetic acid or 5-hydroxyindoleacetic acid. These ...
Young L J - - 1987
Metalloprotein autoreduction is a complex phenomenon composed of multiple reactions, the nature of which depends on the metal, its prosthetic group, and the manner in which they interact with the protein. In all types of autoreduction the protein amino acid side chains are implicated as being a potential source of ...
Draye J P - - 1987
A previously unreported metabolite of mammalian phytanic acid catabolism, 2-oxophytanic acid, was identified by gas chromatography/mass spectrometry analysis. The formation of 2-oxophytanic acid was demonstrated to result from the oxidation of L-2-hydroxyphytanic acid, a reaction catalysed by a rat-kidney-cortex H2O2-generating oxidase. The pH optimum for the L-2-hydroxyphytanate oxidase activity was ...
Ricci G - - 1987
A simple procedure has been developed for the detection of L-amino acid oxidase, glutamine transaminase, pantetheinase, and acylase I in solution and on polyacrylamide gels. The method is based on the strong absorbance at 296 nm of some ketimine rings which can be directly produced by the enzymatic reaction or ...
Rivot J P - - 1987
Treated carbon fiber electrodes were used with differential normal pulse voltammetry (DNPV) for in vivo determination of the relative participation of uric acid (UA) to peak 3 derived between 250-300 mV in the dorsal horn of the spinal cord of anesthetized rats. In vitro, treated carbon fiber electrodes respond linearly ...
Basu D K - - 1987
This study was designed to evaluate the effect of an exogenous free radical generating system consisting of purine plus xanthine oxidase on the isolated rat heart and in particular to assess the possible contribution of arachidonic acid or its metabolites to toxicity produced by this drug combination. Purine plus xanthine ...
Fulco A J - - 1987
In a recent publication (Narhi, L.O. and Fulco, A.J.[1986] J. Biol. Chem. 261, 7160-7169) we described the characterization of a catalytically self-sufficient 119,000 Dalton cytochrome P-450 fatty acid monooxygenase (P-450BM-3) induced by barbiturates in Bacillus megaterium ATCC 14581. We have now examined cell-free preparations from 12 distinct strains of B. ...
Popova L P - - 1987
The influence of abscisic acid (ABA) on carbon metabolism, rate of photorespiration, and the activity of the photorespiratory enzymes ribulose bisphosphate oxygenase and glycolate oxidase in 7-day-old barley seedlings (Hordeum vulgare L. var. Alfa) was investigated. Plants treated with ABA had enhanced incorporation of labeled carbon from (14)CO(2) into glycolic ...
Perotti M E - - 1987
The intracellular localization of D-amino acid oxidase in rat kidney and liver has been investigated using the indirect immunogold postembedding technique. Different fixation and embedding conditions for optimal preservation of antigenicity and fine structure have been tested. Immunolabelling was possible only in tissues embedded in polar resins (glycol methacrylate and ...
Seifert R - - 1987
Both cis and trans unsaturated fatty acids and sodium dodecyl sulfate activated NADPH oxidase in plasma membranes of human neutrophils in the presence of neutrophil cytosol. In contrast, 5,8,11,14-icosatetraynoic acid, saturated fatty acids, esters, peroxides and 4 beta-phorbol 12-myristate 13-acetate, a potent activator of protein kinase C, were inactive. 5,8,11,14-icosatetraynoic ...
Parrott S - - 1987
Escherichia coli K12 grows on 2-phenylethylamine as sole carbon and energy source by converting it, via phenylacetaldehyde, to phenylacetic acid. Phenylacetaldehyde was formed by the action of an inducible amine oxidase and catalase activity was increased sixfold, presumably to ensure removal of the H2O2 that was expected to be a ...
Soltysik S - - 1987
We measured the redox potentials of frozen inactivated L-amino-acid oxidase (L-amino-acid:oxygen oxidoreductase (deaminating), EC 1.4.3.2) and inhibitor-bound (anthranilic acid) enzyme, and compared these redox properties to those of active L-amino-acid oxidase and benzoate-bound D-amino-acid oxidase (EC 1.4.3.3), respectively. The redox properties of the inactive enzyme are similar to the properties ...
Komuniecki P R - - 1987
Ascaris suum L3 larvae isolated from rabbit lungs undergo the third ecdysis to L4 larvae after 3 days in culture under a gas phase of 85% N2/10% CO2/5% O2. The L3 larvae contain substantial malic enzyme activity and are capable of producing small amounts of the reduced organic acids characteristic ...
Abdelsalam E B - - 1987
Organophosphorus compounds are esters of alcohols with phosphoric acids or anhydrides of phosphoric acids with some other acids. The most important groups are the phosphates, phosphorothionates, phosphorothioates, phosphoroamidates, phosphorochloridate and phosphonates. The metabolism of phosphorothionates and phosphorothioates involves initial activation (oxidative desulphuration) followed by hydrolysis of the active metabolites. Activation ...
Tan N H - - 1987
The enzymatic activities of four samples of Malayan cobra venom were investigated. There was significant variation in the contents of L-amino acid oxidase, alkaline phosphomonoesterase, acetylcholinesterase, phospholipase A, 5'-nucleotidase and hyaluronidase. The phosphodiesterase content was, however, constant. Storage of the lyophilized venom powder at 25 degrees C for 1 month ...
Varma S D - - 1986
The potential of ascorbic acid acting against the toxic effects of active oxygen species on the lens has been studied. The active species of oxygen were generated by the action of xanthine oxidase on xanthine. Rat lenses incubated in medium containing xanthine and xanthine oxidase were physiologically damaged, as evidenced ...
Foppoli C - - 1986
S-(1-carboxyethyl)-L-cysteine (1-CEC) and S-(1-carboxypropyl)-L-cysteine (1-CPC) are oxidatively deaminated by L-aminoacid oxidase with consumption of half a mole of oxygen per mole of substrate in the presence of catalase. This reaction gives rise to the corresponding alpha-ketoacids, identified by some chemical and chromatographic tests and by comparison with synthetic compounds. It ...
Taylor D W - - 1986
The deamination of L-amino acids by L-amino acid oxidase, which creates a change in the ionic strength of an HPLC eluent, is used to allow conductometric detection of L-amino acids. An example separation is given, and the conductometric method is compared to other methods of amino acid detection in the ...
Biemond P - - 1986
Xanthine oxidase is able to mobilize iron from ferritin. This mobilization can be blocked by 70% by superoxide dismutase, indicating that part of its action is mediated by superoxide (O2-). Uric acid induced the release of ferritin iron at concentrations normally found in serum. The O2(-)-independent mobilization of ferritin iron ...
Beattie P J - - 1986
Ethylene glycol monomethyl ether (EGME) and ethylene glycol monoethyl ether (EGEE) have recently been shown to be potent reproductive toxicants in laboratory animals. The toxicity of these compounds is believed to be due to their metabolites, methoxyacetic acid (MAA) and ethoxyacetic acid (EAA). Since the primary targets of EGME and ...
Mendez A J - - 1986
A fluorometric assay for triglycerides in nanomole quantities is described. Glycerol is liberated from triglycerides with lipase from Chromobacter viscosum, then converted by glycerol kinase to glycerol-3-phosphate, which is oxidized by glycerol-3-phosphate oxidase, producing H2O2. The H2O2 ultimately forms a peroxidase-catalyzed fluorogen with p-hydroxyphenylacetic acid. The excitation and emission wavelengths ...
Sparks D L - - 1986
The armamentarium of the forensic thanatologist includes the examiner's subjective assessment of bodily changes together with comprehensive evaluation of environmental and associated factors to estimate the postmortem interval (PMI). Of the various objective means, postmortem accumulation of potassium in vitreous humor is a widely used gauge. In view of the ...
Sugihara K - - 1986
The liver enzyme responsible for the reduction of aromatic and heterocyclic hydroxamic acids to the corresponding amides was investigated with salicylhydroxamic acid, benzohydroxamic acid, anthranilhydroxamic acid, and nicotinohydroxamic acid. Rabbit liver cytosol exhibited significant reductase activities toward the hydroxamic acids under anaerobic conditions when supplemented with an electron donor of ...
Mitchell R J - - 1986
The level of indole-3-acetic acid (IAA) in shortleaf pine (Pinus echinata Mill.) roots was increased by inoculation with the ectomycorrhizal fungus Pisolithus tinctorius (Pers.) Coker and Couch. Indole-3-acetic acid oxidase activity was also increased suggesting that the increased level of IAA was the result of increased synthesis. Boron fertilization reduced ...
Reich N O - - 1986
Clofibrate, an antilipidemic drug that acts by a still obscure mechanism, is known to specifically increase up to 30-fold the activity of the hepatic cytochrome P-450 isozyme that omega-hydroxlates lauric acid. The thesis that accelerated catabolism of medium-length fatty acids initiated by omega-hydroxylation contributes significantly to the antilipidemic action of ...
Moreno C M - - 1986
Several substrates and roles have been proposed for D-amino acid oxidase (E.C. 1.4.3.3.); however, there is no proof that they possess the required characteristics to account for the ubiquity, large amounts and great activity of the enzyme as found in diverse cells and tissues. Based on the similar stereoposition of ...
Vo-Quang Y - - 1986
DL-(1-Amino-2-propenyl)phosphonic acid was synthesized through the sequential oxidation, sulfoxide elimination, and deprotection of diphenyl [1-[(benzyloxycarbonyl)amino]-3-(phenylthio)propyl] phosphonate. This analogue of vinylglycine is a strong inhibitor of the alanine racemases from Pseudomonas aeruginosa and Streptococcus faecalis and of the D-Ala:D-Ala ligase from this latter species. This molecule is ineffective against the whole ...
Dabholkar A S - - 1986
In the hepatocytes of 'normal' fetal mice from mothers which were carriers of muscular dysgenesis, catalase and D-amino acid oxidase (DAAO) positive as well as negative peroxisomes were observed. DAAO reaction product was occasionally localized in patches around cell membranes and DAAO-positive peroxisomes were frequently observed near mitochondria.
Youngman R J - - 1986
In the presence of peroxidase, myoglobin or hemoglobin, Tetrachlorodecaoxide (TCDO) forms an active oxygen species which is similar to the product of the polymorphonuclear leucocyte (PMNL) myeloperoxidase reaction and the 'Klebanoff Model' of phagocytosis, but it is also produced under anaerobic conditions. Randomly destructive species such as the free OH ...
Kerckaert I - - 1986
Myocardial H2O2 production was studied by means of the in vivo administration of aminotriazole (AT), which inactivates the catalase-H2O2 complex compound I. Measurements of the residual catalase activity in male and female rats indicate that beta-oxidation of fatty acids in peroxisomes does not contribute in a substantial way to energy ...
Budden S S - - 1986
We describe a relatively new syndrome in four children with characteristic facial dysmorphism, sensorineural hearing loss, severe visual impairment with retinitis pigmentosa, hypotonia, hepatomegaly, and severe developmental delay. Two patients had intracranial hemorrhage secondary to a vitamin K-responsive clotting defect; both had steatorrhea. Liver biopsy specimens in two children showed ...
Yu P H - - 1986
A rapid, sensitive, and specific method for the determination of monoamine oxidase (MAO) activities toward different substrates is described. The assay is based on high-performance liquid chromatographic (HPLC) separation and electrochemical detection of the aldehyde or acid products. The aldehyde metabolic intermediates were observed to be quite stable in 0.1 ...
Mizutani S - - 1985
The degradation of oxytocin (formula; see text) by human placental particulate and soluble fractions, pregnant and non-pregnant sera, and purified enzymes such as microsomal placental leucine aminopeptidase (P-LAP), retroplacental serum P-LAP and placental post-proline endopeptidase, was studied by measuring liberated amino acids with a high performance liquid chromatograph (HPLC). While ...
Price W A - - 1985
L-Tryptophan, the amino acid precursor of serotonin and several other monoamines, has frequently been employed as an adjunct with tricyclic antidepressants and monoamine oxidase inhibitors to increase their effectiveness in treating affective disorders. Combined use of L-tryptophan with electroconvulsive therapy (ECT) has generally not been successful and, in fact, may ...
Herzberg G R - - 1985
An enzymatic assay for the measurement of methanol has been developed. The assay uses alcohol oxidase and peroxidase coupled to the oxidation of 2,2'-azino-di-(3-ethyl)-benzthiazoline-6-sulfonic acid as the chromogen. The assay is linear up to 50 nmol of methanol in a 200-microliters sample and sensitive; 1.25 nmol of methanol in a ...
Carlin G - - 1985
The inhibitory effect of various anti-inflammatory drugs on the xanthine oxidase derived depolymerization of hyaluronic acid was studied. The depolymerization was assayed by repeated viscosity measurements. By using a low xanthine oxidase activity, the decrease in viscosity with time followed first order reaction kinetics and was therefore suitable for kinetic ...
Couto A S - - 1985
Trypomastigote forms (infective) of Trypanosoma cruzi incorporate (3H)-palmitic acid and D-(3H)-galactose into glycolipids. Palmitic acid-labeled acidic glycolipids were partially hydrolyzed with neuraminidase. The labeling of these compounds when the intact cell surface was labeled with galactose oxidase plus NaB3H4 indicates the membrane location of the sialoglycolipids.
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