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Biomedical subjects

J Frezal

Publications and source records attributed to J Frezal.

At least 37 records · Page 2Linked to original sources
PubMed1985

Assignment to chromosome 12 of the gene coding for the human cell surface antigen CD9(p24) using the monoclonal antibody ALB6.

An analysis of 20 independent man-mouse and man-hamster hybrids has shown that the gene coding for the cell-surface protein CD9(p24), a differentiation antigen recognized by the monoclonal antibody ALB6, is located on chromosome 12. A positive correlation was shown between CD9(p24) and chromosome 12 and all other chromosomes were excluded. In addition a synteny was observed between CD9(p24) and LDH-B, a well known marker of chromosome 12 (out of 27 hybrids, 15 were LDH-B+ ALB6+ and 12 were LDH-B-ALB6-). Expression of the antigen in hybrid CH-35K issued from parental fibroblasts possessing a balanced reciprocal translocation 46,X,Y,t(X,12)(q23,q12) indicated that the gene for CD9(p24) is probably localized on 12q12----pter. Monoclonal antibodies ALB6, Ba2 and 602/29 recognize the same protein of molecular weight 21 to 24 KD controlled by a gene located on chromosome 12. It is known that Ba2 and 602/29 recognize two different epitopes but the existence of a third epitope recognized by ALB6 remains to be shown.

Animals↗
PubMed1984

Human genes for glutathione S-transferases.

The tissue distribution of different glutathione S-transferases (GST) is analysed by electrophoresis. The existence of GST"e" (erythrocyte), GST3, GST1, and GST2 is confirmed. GST"e" the fastest and most thermolabile of different GST analysed is observed only in erythrocyte cells. GST3 which migrates more slowly than GST"e" is present in all tissues and cells analysed, excepted for erythrocyte cells in which only GST"e" is observed. GST1 presents a polymorphism with four phenotypes, 1, 1/2, 2, and 0 controlled by three alleles 1, 2, and 0 (null). With the sample of 56 livers analysed the different frequencies obtained are 9%, 5%, 43%, 43% for the phenotypes 1, 1/2, 2, and 0 respectively and 0.074 (p), 0.279 (q), 0.647 (r) for the alleles, 1, 2, and 0 (null). GST2 presents variant patterns due probably, in the majority of cases, to post-synthetic modifications rather than allelic variation. Two new GST are described, GST4 and GST5. GST4 abundant in muscle tissue is a dimeric protein. GST4 forms with GST1 a heterodimeric band. GST5 is observed in brain homogenates. For the chromosome localization the results obtained by man (leucocytes)-mouse somatic cell hybrid analysis indicate that the gene for leucocytes GST is on chromosome 11. This gene is the structural GST3 gene.

Alleles↗
PubMed1984

[Epidemiological and genetic study of 3 congenital cardiopathies with neonatal disclosure].

A familial study was undertaken on 382 probands with transposition of the great vessels, 348 with coarctation of the aorta and 143 with hypoplastic left heart syndrome. It allowed to assess in sibs the frequency of identical congenital heart diseases (respectively 0.15, 0.42 and 3.41%) and of all 7.32%). The epidemiological study did not provide further data worth noting. At the origin of the transposition of the great vessels, tetratogenetic factors are added to genetic factors, whose part is of little importance; hypoplastic left heart syndromes are heterogeneous (recessive autosomal transmission, chromosome abnormalities, sporadic cases). Coarctations of the aorta, which are dependent on different mechanisms are also heterogeneous. It is possible that common factors, whether hereditary or not, play a part on one hand in hypoplastic left heart syndromes and coarctations of the aorta, and, on the other hand, in some congenital heart diseases.

Abortion, Spontaneous↗
PubMed1983

Coreactivation of four inactive X genes in a hamster x human hybrid and persistence of late replication of reactivated X chromosome.

Hamster-human hybrids which contained an inactive human X chromosome were treated by 5-azacytidine. Hypoxanthine guanine phosphoribosyltransferase derepressed hybrids were selected and derepression of three other loci, phosphoglycerate kinase, alpha-galactosidase, and glucose-6-phosphate dehydrogenase were studied. Among 32 hybrids selected for hypoxanthine guanine phosphoribosyltransferase, two were found to be reactivated at four X loci. The independence or nonindependence of the reactivation events will be discussed. No correlation was found between the time of replication and the expression or nonexpression of the X chromosome genes: X chromosomes reactivated at four loci remained late replicating; conversely early replication can exist without the expression of some X genes.

Animals↗
PubMed1982

Congenital lactic acidosis, alpha-ketoglutaric aciduria and variant form of maple syrup urine disease due to a single enzyme defect: dihydrolipoyl dehydrogenase deficiency.

A 6-month-old girl with vomiting, hypotonia and motor retardation was found to have elevated blood lactate, pyruvate, and branched chain amino acids associated with ketoglutaric aciduria. The combination of a congenital lactic acidosis with a variant form of maple syrup urine disease and ketoglutaric aciduria suggested a defect of a single component, common to pyruvate dehydrogenase, to branched chain ketoacid dehydrogenase, and to alpha-ketoglutarate dehydrogenase. Dihydrolipoyl dehydrogenase is the common component (E3). The three enzyme activities and the E3 component activity were found to be reduced in liver and cultured fibroblasts, thus confirming that a single defect of this component can result in a multiple deficiency involving several oxidative decarboxylation reactions.

Acidosis↗
PubMed1982

[Double deficiency of sulfite and xanthine oxidase causing encephalopathy and due to a hereditary anomaly in the metabolism of molybdenum].

The clinical features and biological results in a second patient with a metabolic defect of the molybdenum cofactor are described. The first case was reported in 1978 by Duran et al. Their clinical description was similar with early encephalopathy and myoclonial and dislocation of the lens. Biologically, this condition is characterised by secondary hypo-uricemia and hypo-uricuria due to xanthine oxidase deficiency and by sulphituria, resulting from sulphite oxidase deficiency. These two enzymes have a common hepatic molybdenum cofactor, the structure and metabolism of which are only partially known.

Brain Diseases, Metabolic↗
PubMed1981

Biochemical evidence for the non-inactivation of the steroid sulfatase locus in human placenta and fibroblasts.

Steroid sulfatase activities are significantly higher in placentas obtained after the birth of girls than after the birth of boys, and also in female fibroblasts compared to male strains. This constitutes biochemical evidence for the non-inactivation of the X-linked sulfatase locus. No hydrolytic activity is found in the fibroblasts of ichthyotic boys. Heterozygosity is demonstrated in the fibroblasts of the four mothers studied, as they have steroid sulfatase activity of less or equivalent to the normal male value.

Cells, Cultured↗
PubMed1981

Neonatal glutaric aciduria type II: an X-linked recessive inherited disorder.

A new case of neonatal glutaric aciduria type II is reported. Neonatal acidosis, hypoglycemia, and hyperammonemia were characteristic. The baby died at four days of age. Organic acid analysis revealed massive glutaric aciduria with elevated concentrations of butyric, isobutyric, n-butyric, and isovaleric acid in his urine. The baby's pedigree suggested strongly an X-linked recessive mode of inheritance. Clinically, biochemically, and genetically glutaric aciduria type II is an heterogeneous disorder. The neonatal form is an X-linked inherited disorder which presents early in life, and is associated with metabolic acidosis, hypoglycemia, and hyperammonemia, and leads to death in the neonatal period. The mild form is an autosomal recessive inherited disease which may present even in adults, and is associated with recurrent hypoglycemia without ketosis and usually improves. Nevertheless the same unusual organic acid pattern is observed in both forms. The basic biochemical defect must be distinct and has not been elucidated.

Acidosis↗
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

[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↗