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Biomedical subjects

C Charpentier

Publications and source records attributed to C Charpentier.

At least 127 records · Page 7Linked to original sources
PubMed1981

[Lysinuric protein intolerance: a severe hyperammonemia secondary to l-arginine deficiency (author's transl)]].

Lysinuric protein intolerance is an autosomal recessive disease, due to a defect in intestinal, renal and hepatic dibasic amino acid transport. Two new cases in the same family are reported. The disease appears progressively during the first months of life with failure to thrive, anorexia, vomiting, diarrhea, hepatosplenomegaly, muscular weakness, osteoporosis, anemia, leukothrombocytopenia, hyperammonemia and orotic aciduria after a high-protein intake. Hyperdibasicamino-aciduria was associated with subnormal plasma concentrations of the same aminoacids. Oral l-arginine, l-ornithine, l-lysine, and lysyl-glycine loads confirmed the diagnosis. The supplementation of the diet with l-citrulline resulted in normal levels of blood ammonia. However, hepatosplenomegaly, muscular weakness, osteoporosis remained unchanged and growth was not improved. These may be due to lysine deficiency.

Amino Acid Metabolism, Inborn Errors↗
PubMed1980

Glycine transport by cultured skin fibroblasts from a patient with isolated hyperglycinuria.

Glycine transport is studied in cultured skin fibroblasts from a patient with isolated hyperglycinuria and from five normal subjects. Fibroblasts from the patient take up glycine less well than do cell lines from controls. Kinetic studies are consistent with a single transport system in the patient's and controls' cell lines. Vmax value in the hyperglycinuric lines is normal, but the apparent affinity is always reduced as opposed to those of four different control lines separately tested. Statistical analysis shows significant difference between Km values.

Amino Acid Metabolism, Inborn Errors↗
PubMed1980

[Prognosis of congenital methylmalonic aciduria. Correlations between tolerance to proteins, response to vitamin B12 and enzymatic defect (author's transl)].

In 14 patients with methylmalonic acidemia we studied the correlations between clinical severity (considered in terms of survival and number of acute episodes), daily tolerance to proteins (amounts of leucine, valine, methionine, threonine compatible with good health and a methylmalonic acid excretion below 4 mmol/24h), the in vivo response to vitamin B12 and the nature of the enzymatic defect. This study showed that 2 groups of patients with congenital methylmalonic acidemia may be delineated with respect to prognosis. In patients with complete methylmalonyl CoA mutase deficiency, unresponsive to vitamin B12 in vitro and in vivo, the disease begins most often in the neonatal period and evolution is severe, with frequent acute episodes. Their tolerance to precursor aminoacids is similar to the minimal need (10-15 moles i.e. a total proteic intake of 6-9 g/24 h). None of the 8 patients of this group survived for more than 3 years. Conversely, in the second group (patients with normal in vitro MMCoA mutase activity in the presence of vitamin B12 in excess) the disease begins later, evolution is less severe and tolerance to protein intake is normal or subnormal. However, in this group, in vivo response to vitamin B12 is not constant.

Amino Acid Metabolism, Inborn Errors↗
PubMed1980

[Effects of propionic acid metabolic precursors in biotin-deprived rats].

Biotin deficiency induced in the rat, with a biotin-deficient diet but with added avidin involves clinical symptoms of deficiency as well as an important drop (80%) in propionyl-CoA carboxylase activity in the liver, heart and kidneys. But major biochemical anomalies (ketoacidosis and increased urinary elimination of propionic acid), characteristic of propionic acidaemia due to propionyl-CoA carboxylase deficiency in man, are not observed in the rat. Nevertheless, abnormal urinary elimination of methylcitrate and tiglylglycine reflects an appreciable decrease in the metabolism of propionyl-CoA in these animals. The propionyl-CoA load caused by the administration of metabolic precursors of this substance, mainly L-isoleucine, does not induce important biochemical variations except for excretion of propionylglycine.

Animals↗
PubMed1980

[Alopecia, chronic candidodis, mental retardation and repeated ketoacidosic comas curable by biotin administration: multiple carboxylases deficiency (author's transl)].

Multiple carboxylases deficiency, a recently identified metabolic disease in infants, can be cured by the administration of biotine, a cofactor of the carboxylases: pyruvate, propionyl coenzyme A (CoA), methylcrotonyl CoA, and acetyl CoA. The disorder presents as alopecia, associated with chronic candidosis, psychomotor retardation, and frequent episodes of ketoacidosis coma which responded to biotine treatment. Biological signs, related to the deficiency of the individual enzymes, are observed as hyperlactacidemia, propionic aciduria, and methylcrotonylglycinuria. The metabolic basis of this vitamin-dependent size is still obscure, but the research stimulated by this new disease should clarify the still poorly understood physiological role of this vitamin in humans.

Acidosis↗
PubMed1979

[Propionic acidemia and sodium dipropylacetate].

After administering sodium dipropylacetate to normal rats and biotin-deficient rats, we observed a slight hyperglycinemia, significant constant hyperglycinuria, but no accumulation of propionic acid in the blood or significant urinary elimination. Hepatic propionyl-CoA carboxylase activity, in vivo and in vitro, did not change, neither did sodium dipropylacetate inhibit propionyl-CoA carboxylase nor induce propionic acidemia resulting from a deficiency in this enzyme.

Acyl Coenzyme A↗
PubMed1979

[Emergency treatment of inborn amino errors of amino acid metabolism detected in the neonatal period].

The indications and effects of exchange transfusion, peritoneal dialysis, osmotic diuresis and early feeding have been studied in 28 children with inborn errors of aminoacid metabolism presenting in the neonatal period. Exchange-transfusion has only a transitory and incomplete effect but it is simple and quick. Peritoneal dialysis has a remarkable and often life-saving effect because the blood levels of toxic metabolites are reduced very effectively in organic acidaemias. However the rate of removal may decline if plasma concentrations fall below a critical level (1.2 mmol/L foor leucine). If the dialysis is prolonged for more than 36 hours it may cause hypoprotidaemia. Osmotic diuresis increases the 45 ml/min. However it is of little elimination of methylmalonic acid because the renal clearance is between 15 and 45 ml/min. However it is of little value in maple syrup urine disease, propionic acidaemia or isovaleric acidaemia because the renal clearance of the toxic metabolites is so low. The early re-introduction of low protein high calorie of a low protein and high calorie diet by continuous intragastric feeding is very important. The authors propose a protocol for the treatment of babies presenting inborn errors of aminoacid metabolism in the neonatal period. Peritoneal dialysis should be started as soon as the diagnosis is considered and continued for 24 to 36 hours. An exchange of transfusion shold be undertaken before and after the dialysis, together with an osmotic diuresis if appropriate. Continuous enteral feeding should be given, the quantity being adjusted to the baby's requirements.

Amino Acid Metabolism, Inborn Errors↗
PubMed1978

[Comparative effects of different inhibitors of phenylalanine hydroxylase and dihydropteridine reductase. In vivo and in vitro study in rats].

The effects of inhibitors of phenylalanine hydroxylase and dihydropteridine reductase have been tested in vivo and in vitro to induce classical phenylketonuria and the variant due to dihydropteridine reductase deficiency. In addition two inhibitors of intestinal absorption of phenulalanine were investigated. Blood, urine, and hepatic parameters have been measured and are discussed.

Animals↗
PubMed1977

[Evidence of the haptenic nature of peptidomannans from two yeasts: Saccharomyces oviformis and Candida mycoderma].

Following the observation that it is not possible to immunize rabbits against peptidomannans, extracted from Saccharomyces oviformis and Candida mycoderma, these glycopeptides have been coupled to bovine serum albumine in order to make them immunogenic. Two methods have been used for the coupling: the cyanogen bromide method and the carbodiimide method. Rabbits have been injected intravenously with these conjugates. Using different serologic technics: agglutination, immunodiffusion, counterimmunoelectrophoresis, immunoelectrophoresis we have shown that only peptidomannan-SAB conjugates prepared by the cyanogen bromide method are immunogenic.

Agglutination Tests↗
PubMed1976

[The traps of Guthrie's test].

Presently, 90% of the newborn infants are undergoing screening for phenylketonuria before discharge from the maternity hospital. The tests of detection on urine (search for phenylpyruvic acid) and blood (evaluation of serum phenylalanine) have to be interpreted according to the fetal age, the age at sampling, the conditions of anabolism and the protid intake.

Age Factors↗
PubMed1976

[Isovaleric acidemia. Study and treatment in 3 brothers].

The cases of 3 sibs presenting with isovaleric acidemia are reported. The first infant died when he was 9 day-old. The two others appear to have benefited from a controlled leucine diet which was introduced from the first days on of life. The clinical symptomatology, highly typical of the disease, is described. Diagnosis was not assessed on amino-acids chromatography but on the chromatography of volatile fatty acids. The mode of treatment is described: peritoneal dialysis, with the object of rounding a crucial cape, and overall controlled leucine diet, but supplemented by essential amino-acids.

Amino Acid Metabolism, Inborn Errors↗