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New Pathway of Conversion of Pyridoxal to 4-Pyridoxic Acid
Enzyme, 1976The only enzyme demonstrated so far to catalyze the formation of 4-pyridoxic acid, the final excretory product of vitamin B6, was aldehyde oxidase. In this paper we have presented an evidence that another enzyme, NAD+-dependent aldehyde dehydrogenase, is capable of catalyzing this reaction.
M Stanulović +3 more
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Clinica Chimica Acta, 2017
We quantified pyridoxal 5'-phosphate (PLP), pyridoxal (PL), and 4-pyridoxic acid (PA) in the cerebrospinal fluid (CSF) of children and to investigate the effect of age, sex, epilepsy, and anti-epileptic drug (AED) therapy on these vitamers.CSF samples prospectively collected from 116 pediatric patients were analyzed. PLP, PL, and PA were measured using
Tomoyuki Akiyama +10 more
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We quantified pyridoxal 5'-phosphate (PLP), pyridoxal (PL), and 4-pyridoxic acid (PA) in the cerebrospinal fluid (CSF) of children and to investigate the effect of age, sex, epilepsy, and anti-epileptic drug (AED) therapy on these vitamers.CSF samples prospectively collected from 116 pediatric patients were analyzed. PLP, PL, and PA were measured using
Tomoyuki Akiyama +10 more
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Clinica Chimica Acta, 2017
We quantified pyridoxal 5'-phosphate (PLP), pyridoxal (PL), and 4-pyridoxic acid (PA) in paired serum and cerebrospinal fluid (CSF) samples from children and investigated the effect of age on the concentrations and CSF-to-serum ratios of these vitamers.Serum and CSF samples prospectively collected from 49 pediatric patients were analyzed.
Tomoyuki Akiyama +7 more
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We quantified pyridoxal 5'-phosphate (PLP), pyridoxal (PL), and 4-pyridoxic acid (PA) in paired serum and cerebrospinal fluid (CSF) samples from children and investigated the effect of age on the concentrations and CSF-to-serum ratios of these vitamers.Serum and CSF samples prospectively collected from 49 pediatric patients were analyzed.
Tomoyuki Akiyama +7 more
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A synthesis of the lactone of 5‐pyridoxic acid
Recueil des Travaux Chimiques des Pays-Bas, 1959AbstractThe reduction of dimethyl 2‐methyl‐3‐hydroxypyridine 4,5‐dicarboxylate (I) with sodium borohydride and aluminium chloride gives no pyridoxol but a precursor i.e. the lactone II, corresponding to 5‐pyridoxic acid. No isomeric lactone (III) corresponding to 4‐pyridoxic acid was isolated.
J. P. Wibaut +4 more
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The Journal of Nutritional Biochemistry, 1991
Abstract Plasma and urine from individuals ingesting large amounts of vitamin B 6 contain several unidentified vitamin B 6 metabolites. Based on movement in 6 TLC solvents, elution in HPLC, and ultraviolet and infrared spectra, two of these metabolites have been identified as 5-pyridoxic acid and its lactone.
Thomas A. Pauly +2 more
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Abstract Plasma and urine from individuals ingesting large amounts of vitamin B 6 contain several unidentified vitamin B 6 metabolites. Based on movement in 6 TLC solvents, elution in HPLC, and ultraviolet and infrared spectra, two of these metabolites have been identified as 5-pyridoxic acid and its lactone.
Thomas A. Pauly +2 more
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Analytical Biochemistry, 1986
Simultaneous and direct assays of pyridoxal, pyridoxal-5'-phosphate, and pyridoxic acid in human serum are described. The method applied is based on the reaction of these compounds with beryllium in an ammoniacal medium to yield highly fluorescent derivatives.
Soledad Rubio +3 more
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Simultaneous and direct assays of pyridoxal, pyridoxal-5'-phosphate, and pyridoxic acid in human serum are described. The method applied is based on the reaction of these compounds with beryllium in an ammoniacal medium to yield highly fluorescent derivatives.
Soledad Rubio +3 more
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Neurochemical Research, 1985
Previous studies from this laboratory have shown that pyridoxal-5'-sulphate, the synthetic analogue of pyridoxal phosphate, causes epileptic seizures including tonic-clonic convulsions. These seizure activities are prevented or reversed by GABA or muscimol.
Manuchair Ebadi +2 more
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Previous studies from this laboratory have shown that pyridoxal-5'-sulphate, the synthetic analogue of pyridoxal phosphate, causes epileptic seizures including tonic-clonic convulsions. These seizure activities are prevented or reversed by GABA or muscimol.
Manuchair Ebadi +2 more
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The American Journal of Clinical Nutrition, 1986
A high-performance liquid chromatography method for quantitation of urinary 4-pyridoxic acid excretion is presented. Urine samples were treated with HCl to form 4-pyridoxic acid lactone. Acid-treated urine samples were diluted and analyzed by cation-exchange chromatography involving post-column alkalinization and fluorescence detection.
Johan B. Ubbink +3 more
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A high-performance liquid chromatography method for quantitation of urinary 4-pyridoxic acid excretion is presented. Urine samples were treated with HCl to form 4-pyridoxic acid lactone. Acid-treated urine samples were diluted and analyzed by cation-exchange chromatography involving post-column alkalinization and fluorescence detection.
Johan B. Ubbink +3 more
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Russian Journal of General Chemistry, 2008
The mechanism of chemical transformations of pyridoxal and pyridoxal 5′-phosphate condensation products with amino acids is studied by kinetic measurements. The Schiff bases are shown to be fairly stable in neutral media. In acid media, the Schiff bases are hydrolyzed into the initial components. In alkaline media, cleavage of α-hydrogen from the amino
I. T. Tuleberdiev, F. V. Pishchugin
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The mechanism of chemical transformations of pyridoxal and pyridoxal 5′-phosphate condensation products with amino acids is studied by kinetic measurements. The Schiff bases are shown to be fairly stable in neutral media. In acid media, the Schiff bases are hydrolyzed into the initial components. In alkaline media, cleavage of α-hydrogen from the amino
I. T. Tuleberdiev, F. V. Pishchugin
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Reactions of pyridoxal with aromatic carboxylic acids in alcoholic medium
Russian Journal of General Chemistry, 2017© 2017, Pleiades Publishing, Ltd. Reactions of pyridoxal with benzoic acid and its derivatives in alcoholic medium afforded alkoxyfuropyridinium salts with potential biological activity.
Alexey V. Trifonov +5 more
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