Results 211 to 220 of about 13,373 (259)

Methylmalonic Acid Inhibits Respiration in Rat Liver Mitochondria

The Journal of Nutrition, 1995
Methylmalonic acid (MMA), which accumulates and is excreted in urine in mammals during vitamin B-12 deficiency, has been reported to inhibit succinate dehydrogenase, an enzyme involved in the mitochondrial tricarboxylic acid (TCA) cycle in rat liver.
S, Toyoshima, F, Watanabe, H, Saido, K, Miyatake, Y, Nakano   +4 more
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Colorimetric Method for Determination of Urinary Methylmalonic Acid

Annals of Clinical Biochemistry: International Journal of Laboratory Medicine, 1979
The colorimetric method for the determination of methylmalonic acid by coupling with diazotised p-nitroaniline has been re-examined. Extraction of the diazotised product into amyl alcohol and tetra-methyl ammonium hydroxide considerably increases its stability and sensitivity and reduces background absorbance.
A, Westwood, W, Taylor, G, Davies
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METABOLIC PRECURSORS OF METHYLMALONIC ACID IN VITAMIN-B12 DEFICIENCY

The Lancet, 1967
Abstract Valine, isoleucine and sodium propionate have been investigated as precursors of urinary methylmalonic acid in patients with vitamin B12 deficiency. Valine was administered to fifteen patients with vitamin B12 deficiency and provoked an increased excretion of methylmalonic acid in all cases. The same dose of valine had no effect on excretion
D, Gompertz, J H, Jones, J P, Knowles
openaire   +3 more sources

Serum cobalamin and methylmalonic acid in Alzheimer dementia

Acta Neurologica Scandinavica, 2009
The cobalamin status was evaluated in Alzheimer dementia (n = 26), other dementias (n = 24), various gerontopsychiatric disorders (n = 25), and in neuro-psychiatrically healthy controls (n = 20). Supplementing serum cobalamin we measured methylmalonic acid (MMA), a metabolite accumulating early in cobalamin deficiency.
M O, Kristensen, N C, Gulmann, J E, Christensen, K, Ostergaard, K, Rasmussen   +4 more
openaire   +2 more sources

Methylmalonic acid induces excitotoxic neuronal damage in vitro

Journal of Inherited Metabolic Disease, 2000
Methylmalonic aciduria (McKusick 251000) comprises a group of inherited metabolic disorders caused by deficient L-methylmalonyl-CoA mutase (EC 5.4.99.2) or its cofactor 5'-deoxyadenosylcobalamin that lead to an accumulation of methylmalonic acid (MMA) in body fluids as well as brain tissue (up to 1 mmol/L or even higher). Although the clinical spectrum
S, Kölker, B, Ahlemeyer, J, Krieglstein, G F, Hoffmann   +3 more
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Methylmalonic Acid Excretion in Vitamin B₁₂ Deficiency

British Journal of Haematology, 1966
methylmalonic acid was first isolated from pooled human urine in 1957 by Thomas and Stalder and convincing evidence has since been obtained to show that in man the isomerization of l‐methylmalonyl‐Co A to succinyl‐Co A is dependent on the B12 coenzyme dimethylbenzimidazolyl cobamide (White, 1962).
H V, Bashir, H, Hinterberger, B P, Jones
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The assay of methylmalonic acid in urine

Clinica Chimica Acta, 1972
Abstract The assay of methylmalonic acid in urine by modifications of the method of Giorgio and Plaut 5 , together with the use of a three wavelength correction is described. This revised procedure made possible the detection of small increases in the output of methylmalonic acid in vitamin B 12 deficiency which could not be estimated by the ...
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Gas chromatographic determination of urinary methylmalonic acid

Analytical Biochemistry, 1967
Abstract A method for the determination of methylmalonic acid in urine has been developed. The method consists of essentially two operations: ( 1 ) A separation of methylmalonic acid from most of the urinary components by ion-exchange chromatography.
Norman E. Hoffman, Joseph J. Barboriak
openaire   +1 more source

Urinary Methylmalonic Acid to Detect Vitamin B12 Deficiency

JAMA: The Journal of the American Medical Association, 1995
To the Editor. —In a recent Questions and Answers section, Dr Upshaw 1 asked which test to use to establish true functional vitamin B 12 deficiency. Dr Carmel, in reply, suggested the serum methylmalonic acid (MMA) assay noting, however, its limitations of expense and specificity. Recently, a review article on this subject recommended the urinary MMA
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Automated methylmalonic acid assay

Analytical Biochemistry, 1971
J M, Gawthorne, J, Watson, E L, Stokstad
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