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M Duran

Publications and source records attributed to M Duran.

At least 181 records · Page 10Linked to original sources
PubMed1991

Gas chromatography method for the separation of amino acids enantiomers in plasma and urine. Application in a case of short bowel syndrome.

Urinary amino acids were isolated from the urine of healthy controls and a patient with a short bowel syndrome. Following derivatization with isopropyl alcohol/HCl and trifluoroacetic anhydride the amino acid enantiomers were separated by gas chromatography on a Chirasil-L-Val column. All subjects excreted D-alanine (10-30% of total Ala). The percentage D-alanine was higher in the patient with the short bowel syndrome. The excretion of D-alanine did not correlate with the D-lactate excretion. An intestinal origin for the D-amino acids is the most probable explanation.

Adolescent↗
PubMed1991

Medium- and long-chain 3-hydroxymonocarboxylic acids: analysis by gas chromatography combined with mass spectrometry.

Medium- and long-chain 3-hydroxymonocarboxylic acids represent intermediates in the beta-oxidation of fatty acids: they accumulate in the plasma of patients with an inherited deficiency of long-chain 3-hydroxyacylcoenzyme A dehydrogenase. 3-Hydroxy acids with chain lengths varying from 6 to 16 were synthesized by a Reformatzky reaction. Capillary gas chromatography of the pertrimethylsilyl derivatives was performed on a CP-Sil 19 CB column, coupled to a quadrupole mass spectrometer in the electron impact mode. Calculation of the retention indices showed that the separation of the 3-hydroxy acids from the homologous straight-chain fatty acids may be troublesome, stressing the need for mass spectrometric identification.

Carboxylic Acids↗
PubMed1991

3-Hydroxydicarboxylic aciduria due to long-chain 3-hydroxyacyl-coenzyme A dehydrogenase deficiency associated with sudden neonatal death: protective effect of medium-chain triglyceride treatment.

Two siblings were found to be affected by long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency, one of which died suddenly and unexpectedly on the 3rd day of life suffering from extreme hypoketotic hypoglycaemia. The younger sibling started to have feeding problems, lowered consciousness, and liver dysfunction at the age of 5 months. Her urine contained large amounts of C6-C14 3-hydroxydicarboxylic acids and conjugated 3-hydroxyoctanoic acid, as verified by gas chromatography/mass spectrometry. Plasma long-chain acylcarnitine was increased. A clue to the diagnosis was given by the results of a phenylpropionic acid loading test. This revealed small, but significant amounts of conjugated 3-hydroxyphenylpropionic acid (phenylhydracrylic acid) in the patient's urine. Subsequently, the activity of long-chain 3-hydroxyacyl-CoA dehydrogenase was found to be deficient in cultured skin fibroblasts. Based on the findings obtained by a medium-chain triglyceride load, a diet enriched in this type of fat was prescribed. On this regimen the patient started to thrive, signs of cardiomyopathy disappeared, and her liver function normalized.

3-Hydroxyacyl CoA Dehydrogenases↗
PubMed1991

Infantile isolated sulphite oxidase deficiency: report of a case with negative sulphite test and normal sulphate excretion.

We present the clinical and biochemical data of a patient with infantile isolated sulphite oxidase deficiency with late onset of symptoms. A comparison of the biochemical parameters is made with the neonatal type of this disease and with the data of described patients with the combined defect of sulphite oxidase and xanthine oxidase, due to molybdenum cofactor deficiency. False-negative sulphite dip stick test as a pitfall in the diagnosis of sulphite oxidase deficiency is discussed.

Humans↗
PubMed1991

[Molecular genetic aspects of phenylketonuria (PKU)].

In phenylketonuria (PKU) usually there is a defect in the phenylalanine hydroxylase (PAH) gene. Eight restriction fragment length polymorfisms (RFLP's) in the PAH gene together constitute the haplotype. A considerable number of mutations, responsible for the gene defect, some of which are rather frequent, have been described. Here, we present the first results of investigations on the distribution of haplotypes and mutations in PKU patients in the Netherlands. A short literature review is presented.

Haplotypes↗
PubMed1990

Sialyl-alpha 2-6-mannosyl-beta 1-4-N-acetylglucosamine, a novel compound occurring in urine of patients with beta-mannosidosis.

Human beta-mannosidosis urine was fractionated by gel permeation chromatography on Bio-Gel P-2 and by high performance liquid chromatography on Partisil 10 SAX. Besides the disaccharide Man beta 1-4GlcNAc as the major component, a sialic acid-containing compound was detected in an amount of 10% compared to that of Man beta 1-4GlcNAc. Structural characterization of the oligosaccharide and of its reduced analogue by sugar composition analysis, methylation analysis, gas-liquid chromatography-mass spectrometry, and 500-MHz 1H NMR spectroscopy gave conclusive evidence for a novel urinary constituent: NeuAc alpha 2-6Man beta 1-4GlcNAc. This linear trisaccharide can be considered as the result of an alpha 2-6-sialylation of the major accumulating compound, Man beta 1-4GlcNAc. The hitherto unknown linkage between sialic acid and mannose was shown to be susceptible to sialidase digestion.

Carbohydrate Sequence↗
PubMed1990

Rapid diagnosis of 3-hydroxy-3-methylglutaryl-coenzyme A lyase deficiency via enzyme activity measurements in leukocytes or platelets using a simple spectrophotometric method.

Patients with 3-hydroxy-3-methylglutaric aciduria due to a deficiency of 3-hydroxy-3-methylglutaryl Coenzyme A lyase usually present with a life-threatening crisis of hypoglycemia, metabolic acidosis and hyperammonemia. Diagnosis of this inborn error of leucine degradation is usually based upon gas-chromatographic analysis of organic acids in a patient's urine. In this paper we describe a simple spectrophotometric method allowing the activity of HMG-CoA lyase to be measured in leukocytes or platelets within a few hours, thus contributing to a rapid, unequivocal diagnosis and subsequent treatment. The validity of the method was established by demonstrating a deficient activity of HMG-CoA lyase in two patients with 3-hydroxy-3-methylglutaric aciduria. Furthermore, using this method, heterozygote detection can be done with great reliability.

Blood Platelets↗
PubMed1990

Accumulation of mannosyl-beta(1----4)-N-acetylglucosamine in fibroblasts and leukocytes of patients with a deficiency of beta-mannosidase.

Cultured fibroblasts from two brothers with beta-mannosidosis were shown to accumulate the disaccharide mannosyl-beta(1----4)-N-acetylglucosamine in amounts of 52 and 68 nmol/mg protein. Structural identification of the Man beta(1----4)GlcNAc, isolated by HPLC, was performed by 500-MHz 1H-NMR spectroscopy and sugar composition analysis. Control fibroblasts did not contain a detectable amount of Man beta(1----4)GlcNAc. The disaccharide was also present in leukocytes from these patients, but not in controls, as could be demonstrated by thin-layer chromatography and sugar composition analysis. However, the amounts in leukocytes (5 and 6 nmol/mg protein) were much smaller than those in fibroblasts.

Cells, Cultured↗
PubMed1990

O-phosphohydroxylysinuria: a new inborn error of metabolism?

An abnormal ninhydrin positive compound was observed in the urine of two unrelated patients with neurological abnormalities. The compound was isolated by cation exchange followed by preparative paper chromatography and finally purified via cation exchange column chromatography. Its identification as O-phosphohydroxylysine resulted from FAB mass spectrometry and NMR spectroscopy. Chemical synthesis confirmed the structure. It was tentatively postulated that these patients had a defect of the metabolism of hydroxylysine, viz., a deficiency of the enzyme O-phosphohydroxylysine phospholyase.

Adolescent↗
PubMed1990

Quasi-moyamoya disease and heterozygosity for homocystinuria in a five-year-old girl.

We report a patient with quasi-Moyamoya disease who presented with acute left hemiparesis. Routine metabolic evaluation was normal. However, by performing a methionine loading test and measurement of cystathionine synthase activity in cultured fibroblasts the diagnosis of heterozygosity for homocystinuria (HC) was established. Only recently it has been shown that heterozygosity for HC is a risk factor for premature cerebrovascular disease in adults. The present case suggests that also in children with cerebrovascular disorders the analysis of its pathogenesis should include extensive metabolic studies on homocysteine metabolism.

Arterial Occlusive Diseases↗