Results 161 to 170 of about 5,521 (201)

Oxidation of 3‐hydroxykynurenine. An EPR investigation

Journal of Heterocyclic Chemistry, 1990
AbstractA weak alkaline solution of 3‐hydroxykynurenine was oxidized using potassium ferricyanide. A stable epr signal was recorded, probably arising from a phenoxazine intermediate. A plausible radical mechanism for this reaction is presented.
A. BOLOGNESE, BONOMO, Raffaele, R. CHILLEMI, S. SCIUTO   +3 more
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The Modification of Proteins by 3-Hydroxykynurenine

Experimental Eye Research, 1993
The autoxidation and reactivity towards proteins of 3-hydroxykynurenine, a tryptophan metabolite found in the human lens, has been studied. At neutral pH, 3-hydroxykynurenine was readily oxidized using molecular oxygen with the formation of several coloured products.
G M, Stutchbury, R J, Truscott
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Determination of endogenous 3-hydroxykynurenine in plasma

Microchemical Journal, 1984
Abstract A method is described which permits determination of 3-hydroxykynurenine ( l -3-(2-amino-3-hydroxybenzoyl)-alanine), a metabolite of tryptophan, in plasma with a limit of detection of less than 0.1 pmol. This compound can be extracted by means of adsorption onto a strong anion-exchange resin at pH 9.5 in the presence of an antioxidant ...
Stig Allenmark, Maj-Britt Bengtsson, Kerstin Nordström, Claes Hallert   +3 more
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Biphotonic ionization of kynurenine and 3-hydroxykynurenine

Journal of Photochemistry and Photobiology A: Chemistry, 2007
Abstract The photoionization of kynurenine (KN) and 3-hydroxykynurenine (3OHKN) in aqueous solutions proceeds via a biphotonic mechanism. The precursors for ionization are the triplet states TKN and T3OHKN, absorbing the second light quantum. The addition of solvated electrons to the parent molecules with the rate constant 2.0 × 1010 M−1 s−1 results ...
O.A. Snytnikova, P.S. Sherin, Yu.P. Tsentalovich   +2 more
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3-Hydroxykynurenine in human urine

Clinica Chimica Acta, 1960
Abstract An investigation has been made into the determination of 3-hydroxykynurenine in urine. Urine was passed through an ion-exchange resin and 3-hydroxykynurenine determined in the 5N hydrochloric acid eluate by means of the molybdate-phosphate reaction.
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Identification of 3-Hydroxykynurenine and Xanthurenic Acid and Quantitation of 3-Hydroxykynurenine Transaminase Activity Using HPLC with Electrochemical Detection

Journal of Liquid Chromatography & Related Technologies, 1998
Abstract Identification of 3-hydroxykynurenine and xanthurenic acid and determination of 3-hydroxykynurenine transaminase activity using HPLC with electrochemical detection (HPLC-ED) are described using mosquito larval samples as testing materials.
J. Li, G. Li
openaire   +1 more source

Epigallocatechin 3-gallate attenuates neuronal damage induced by 3-hydroxykynurenine

Toxicology, 2004
3-Hydroxykynurenine (3-HK), which is an endogenous metabolite of tryptophan in the kynurenine pathway, is a potential neurotoxin in several neurodegenerative disorders. Epigallocatechin 3-gallate (EGCG), a major compound of green tea, is recognized as a promising natural substance for protection against neuronal diseases.
Ji Hoon Jeong
exaly   +3 more sources

3-hydroxykynurenine as O2⨪ scavenger in the blowfly, Aldrichina grahami

Biochemical and Biophysical Research Communications, 1986
We studied the distribution of O2-.-scavenging activity in 6-day-old larvae of Aldrichina grahami. Total activity was highest in the muscle. The specific activity per milligram of protein in the Malpighian tubules was highest, 10 times the highest elsewhere. Most of the O2-. scavenging activity in muscle depended on superoxide dismutase.
N, Goshima, A, Wadano, K, Miura
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Isolation of Kynurenine and 3-Hydroxykynurenine from Human Pathological Urine

Nature, 1955
IN 1951, 3-hydroxyanthranilic acid was isolated from the urine of a patient with pulmonary tuberculosis after administration of 1-tryptophan1. This result caused us to examine the urine of various subjects, including some tuberculous patients not receiving special diet or supplementary administration of tryptophan.
L, MUSAJO, C A, BENASSI, A, PARPAJOLA
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A new fluorimetric method for the determination of 3-hydroxykynurenine

Clinica Chimica Acta, 1970
Abstract A new fluorimetric assay for the determination of 3-hydroxykynurenine has been developed, which is based on the reaction of the compound with p -toluenesulfonyl chloride in basic condition to yield a fluorescent product. In combination with the thin-layer chromatographic technique this assay has been used to estimate the urinary excretion ...
M, Watanabe, Y, Watanabe, M, Okada
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