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P Divry

Publications and source records attributed to P Divry.

At least 91 records · Page 5Linked to original sources

Hypoxanthine and xanthine concentrations determined by high performance liquid chromatography in biological fluids from patients with xanthinuria.

In the present paper, we report the biochemical features of six cases of xanthinuria. For these studies, the concentrations of hypoxanthine and xanthine have been measured in urine, plasma and also erythrocyte samples by a rapid, sensitive high performance liquid chromatographic (HPLC) method. The analyses of plasma and erythrocyte samples require a very sensitive method relative to physiological concentrations and rigorous sampling conditions in order to achieve accurate results. In the cases reported in the literature, total oxypurine levels (hypoxanthine + xanthine) have been generally measured in plasma and urine by an enzymatic spectrophotometric method. In our studies, using HPLC, we found that xanthine is the major oxypurine compound in plasma and urine samples from patients with xanthinuria. In erythrocytes, a biological sample which has not been analysed up to now, we found that xanthine is present at high concentrations whereas it is not detectable in erythrocytes from healthy subjects.

Adult↗

Defective succinic semialdehyde dehydrogenase activity in 4-hydroxybutyric aciduria.

Succinic semialdehyde dehydrogenase deficiency has been demonstrated in a fourth patient with 4-hydroxybutyric aciduria. Lysates of freshly isolated lymphocytes and cultured lymphoblasts of the patient had much lower than control activity in the conversion of U-14C-4-aminobutyric acid to 14C-succinic acid in an assay designed to estimate succinic semialdehyde dehydrogenase utilizing endogenous 4-aminobutyrate transaminase. Lymphocyte and lymphoblast lysates of the patient accumulated U-14C-succinic semialdehyde when incubated with U-14C-4-aminobutyric acid and NAD+ whereas none could be detected in controls. Assays using U-14C-succinic semialdehyde as substrate for succinic semialdehyde dehydrogenase in lysates of cultured lymphoblasts characterized the patient as having a severe deficiency of succinic semialdehyde dehydrogenase. The data indicate that defective activity of succinic semialdehyde dehydrogenase is responsible for 4-hydroxybutyric aciduria.

4-Aminobutyrate Transaminase↗

Gas chromatography--mass spectrometry (GC--MS) diagnosis of two cases of medium chain acyl-CoA dehydrogenase deficiency.

Two patients with hypoketotic hypoglycaemia and dicarboxylic aciduria are described. Studies of their urinary organic acids by gas chromatography-mass spectrometry (GC-MS) showed an excretion of dicarboxylic acids (adipic suberic and sebacic acids), unsaturated dicarboxylic acids (cis-octenedioic and decenedioic acids),5-hydroxyhexanoic acid, hexanoyl-glycine and suberylglycine. Deficiency of the medium chain acyl-CoA dehydrogenase (MCAD) in fibroblasts was documented for both children. Despite a similar presentation (hypoglycaemic coma), organic acid profile (dicarboxylic aciduria and suberylglycine excretion) and enzyme deficiency (MCAD), they did not respond similarly to glucose infusion.

Acyl-CoA Dehydrogenase↗

[Medium chain acyl-CoA dehydrogenase deficiency. Apropos of a case with demonstration of this enzyme deficiency].

The medium chain acyl-CoA deshydrogenase defect: a new inherited metabolic disorder. This enzymatic defect blocks the catabolism of non esterified fatty acids during fasting. Thus, this disease is revealed by a coma due to hypoglycemia in a young child; the presence of dicarboxylic aciduria in such a situation is the main evidence for this diagnosis. Finally, the enzymatic studies performed on skin fibroblasts show a defect in medium chain acyl-CoA deshydrogenase. When a child is investigated away from a coma episode, the ketotic diet induces dicarboxylic aciduria but must be performed in an intensive care unit for its dangers.

Acyl-CoA Dehydrogenase↗

General (medium-chain) acyl-CoA dehydrogenase deficiency (non-ketotic dicarboxylic aciduria): quantitative urinary excretion pattern of 23 biologically significant organic acids in three cases.

Urinary analysis of the pattern of 23 organic acid metabolites derived from fatty acids in three patients with general (medium-chain) acyl-CoA dehydrogenase deficiency was performed. Although there exist quantitative differences in the excreted amounts of the different metabolites in the three patients the qualitative picture was the same. The excretion of adipic, suberic and sebacic acids was substantial, whereas that of dodecanedioic acid was within or just above control limit. The monounsaturated C6-C10-dicarboxylic acid excretion was only marginally or not increased. 5-OH-hexanoic acid and hexanoylglycine were excreted in excessive amounts, whereas 7-OH-octanoic acid, 9-OH-decanoic acid, octanoylglycine and decanoylglycine were excreted in limited amounts. The excreted amounts of 6-OH-hexanoic, 8-OH-octanoic and 10-OH-decanoic acids were not or only marginally elevated compared to controls. In one of the patients the excretion of ethylmalonic and methylsuccinic acids was enhanced, whereas the excretion of these two acids in the two other patients was comparable to that in controls. The urinary excretion of hexanoic, octanoic, decanoic and dodecanoic acids was just a little above the control limit, whereas the esterified hexanoic and octanoic acids were excreted in appreciable amounts. It is argued that the microsomal omega- and omega-1-oxidation systems are involved in the dicarboxylic and omega-1-OH-monocarboxylic acids formation at C10 and C12 level and that the C8-C6-dicarboxylic and omega-1-OH-monocarboxylic acids are formed from higher chained acids by beta-oxidation in both mitochondria and peroxisomes.

Acyl-CoA Dehydrogenase↗

Urinary excretion of deuterated metabolites in patients with tyrosinemia type I after oral loading with deuterated L-tyrosine.

1. The metabolic fate of orally given deuterated L-tyrosine, 50 mg/kg body weight, was investigated in seven patients with tyrosinemia type I in order to obtain evidence that the primary defect is at the level of fumarylacetoacetase. 2. The absence of fumarylacetoacetase could be proved in liver biopsy specimens obtained from four patients. 3. All patients excreted deuterated succinylacetoacetate and deuterated succinylacetone was detected in six out of seven. The total amount of these compounds was rather low; maximal 8.3% of the dose. The peak of the excretion occurred 3-6 h after loading, indicating an endogenous formation of the metabolites. 4. All patients excreted deuterated 4-hydroxyphenyl acids, probably reflecting secondary 4-hydroxyphenylpyruvate dioxygenase deficiency connected with liver damage. 5. No evidence for other secondary routes of tyrosine metabolism was found.

4-Hydroxyphenylpyruvate Dioxygenase↗

Dicarboxylic aciduria due to medium chain acyl CoA dehydrogenase defect. A cause of hypoglycemia in childhood.

Dicarboxylic aciduria was found during hypoglycemic episode in a 14 months old girl. Her brother had died at the age of 4 years during febrile illness. A ketogenic diet induced in this patient a severe hypoglycemia. Urinary organic acid profile exhibited abnormal excretion of the C6-C10 dicarboxylic acids (adipic-suberic-sebacic) and related metabolites (5 hydroxyhexanoic, hexanoylglycine, suberyl glycine). This pattern suggested a defect in fatty acids beta oxidation. Plasma carnitine values was within control limits. Similar clinical findings and urinary organic acids excretion have been described in 6 patients since the initial case of Gregersen. Enzymatic studies on cultivated fibroblasts from our patient showed a defect in medium chain CoA dehydrogenase. The treatment of this disease consists of glucose infusion during attacks and prevention of fasting. This rare disease must be considered in a child with non ketotic hypoglycemia or Reye's syndrome.

Acyl-CoA Dehydrogenases↗

Effect of oral lipid administration on glucose homeostasis in small-for-gestational-age infants.

The metabolic effect of feeding with 1.3 g/kg bw lipids (67% medium chain triglycerides) was studied in 15 small-for-gestational age (SGA) term infants. It was compared to a control group of 7 SGA term infants, to 7 term infants with an appropriate birth weight (AGA) and to 7 AGA preterm infants. Plasma glucose concentration rose from (M +/- SE) 3.6 +/- 0.2 to 4.4 +/- 0.3 mmol/l at 30 min in SGA term infants (p less than 0.01). A similar increase was observed in AGA term and preterm infants. The lipid load produced no change in plasma glucagon concentration but a significant increase in insulin/glucagon molar ratio was observed in AGA term infants only. In term SGA infants, the disappearance rate of glucose in plasma after the lipid load was similar to the control: 1.24% per min. The evolution of blood pyruvate and lactate concentration was not modified by the lipid load. Despite lower concentrations of free fatty acids and ketone bodies (KB) in SGA infants than in AGA term infants, the lipid load induced a 120% increase of ketone bodies in SGA infants and a 40% increase only in AGA infants. These data show that these lipids produce a hyperglycemic response in SGA infants as in AGA infants without any change of the disappearance rate of glucose. They suggest that these lipids can stimulate gluconeogenesis and ketogenesis in SGA infants.

Administration, Oral↗

Serum orosomucoid concentration in newborn infants.

Serum orosomucoid concentration was measured by laser nephelometry in 1970 serum samples collected from 1170 full term and preterm infants. The determinations were carried out in 1 h. Reference values are given: they show that the low levels at birth are influenced by gestational age. The concentrations increase rapidly during the first week in all infants, the adult values being reached by 10 months of age. High levels of orosomucoid concentration were detected in 85% of the infants with severe bacterial infections. Serum orosomucoid concentration proved less valuable in viral and parasitic infection. Twenty-six per cent of the sick infants without infection had a slightly elevated orosomucoid level which decreased rapidly. In the bacterial infections the evolution of serum orosomucoid concentration followed the clinical course. Thus serum orosomucoid concentration was a useful parameter for diagnosis and monitoring of bacterial infection in neonates.

Bacterial Infections↗

Laser nephelometry of orosomucoid in serum of newborns: reference intervals and relation to bacterial infections.

Orosomucoid was evaluated by laser-nephelometry in 1790 sera collected from 1170 newborns. Within-run precision (CV) was 2.1 to 4.2%, between-run 2.9 to 5.2%. Results correlated well with radial immunodiffusion (r = 0.989). Results can be obtained within 1 h. Orosomucoid concentrations in serum at birth range from 130 to 200 mg/L and are influenced by gestational age during the first two days of postnatal life. Thereafter, the values increase very rapidly in the first week of life, concentrations being the same as in adults by about 10 months. In 66 of 78 cases of severe bacterial infections, orosomucoid concentrations were above normal. Evidently, serum orosomucoid constitutes an useful index in diagnosis and monitoring of bacterial infections in the neonatal period.

Adult↗

Uric acid, monosodium urate and ammonium urate urinary relative saturations in normo-uricuric calcium oxalate stone formers.

Monosodium urate (NaU), ammonium urate (NH4U) and uric acid (UA) urinary relative saturations were studied in 15 normo-uricuric calcium oxalate (CaOx) recurrent stone formers whose CaOx relative saturation was identical to age- and sex-matched controls. NaU and NH4U relative saturations were constantly below 1 and not higher in stone formers than in controls, suggesting that heterogeneous nucleation is an unlikely mechanism of CaOx stone formation in vivo. Such values of NaU relative saturation would also tend to rule out any change in the CaOx formation product or urinary inhibitory activity. However, at a given urinary flow rate, NaU relative saturation was suggestively higher in stone formers than in controls. Some disturbance in the equilibrium between NaU and urinary inhibitors might then exist even in normo-uricuric CaOx stone formers.

Animals↗

[Glutaric aciduria. 1 new case].

A 4 year old girl with mild mental retardation presented with convulsions, coma and hepatomegaly. She died rapidly. The main biochemical findings were hypoglycaemia, metabolic acidosis, generalised aminoaciduria, elevation of the plasma and urine alpha-amino adipic acid, massive urine excretion of glutaric and glutaconic acids with traces of alpha-hydroxyglutaric acid. The diagnosis of glutaric aciduria was confirmed by the low activity of glutaryl CoA dehydrogenase in liver tissue. This diagnosis should be considered in children with progressive neurological disorders (dystonia, choreoathetosis) and in children with an illness similar to Reye's syndrome.

Amino Acid Metabolism, Inborn Errors↗