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D Rochu

Publications and source records attributed to D Rochu.

32 records · Page 2Linked to original sources
PubMed1987

Human albumin genetic variants: an attempt at a classification of European allotypes.

The relative mobility of albumin and proalbumin genetic variants was estimated by means of cellulose acetate electrophoresis performed with three buffer systems at different pH (8.6, 5.0, and 6.9) after addition of a reference protein and dilution of sera. Numerous experiments using samples of reference variants corroborated the accuracy and reproducibility of this technique. The estimation of the variants' relative mobility at three pH allowed us to distinguish three fast-moving variants (Gent, Vanves, and Reading) and five slow-moving variants (Sondrio, Roma, Christchurch, Lille, and B) in the French population. The frequency of alloalbuminemia in this population is .0004 and is characterized by the high occurrence of albumin B and of the two proalbumin variants, Christchurch and Lille. In order to classify the variants of European origin, the methodology that we developed, owing to its more resolutive possibilities, should be employed as a first step in their identification until establishment of a structural nomenclature making mention of the amino acid substitution characterizing each variant.

Albumins↗
PubMed1986

Waldenström's macroglobulinemia in monozygotic twins.

This paper reports a unique familial occurrence of Waldenström's macroglobulinemia (WM) in monozygotic twins. The determination of twin monozygosity has been performed by electrophoretic and immunological typing of genetic systems (erythrocyte blood groups, leucocyte antigens and serum protein polymorphism). The two monoclonal IgM differ one from the other by their light chain type and their idiotypic determinants. Although a genetic predisposition to WM exists in these twins, the gene recombination leading to idiotypic specificity and light chain assortment occurs independently of the monoclonal malignant involvement.

Aged↗
PubMed1986

Occurrence of normal circulating proalbumin in a hemophilic A patient after acute hepatitis related to the delta virus.

Circulating proalbumin in humans has been described in two distinct events: genetic variants of proalbumin related to mutations at the cleavage site, and normal proalbumin related to an abnormal cleaving enzyme system. We report a case of acquired proalbuminemia that appeared after an acute episode of hepatitis related to the delta agent, in a chronic carrier of hepatitis B virus. This component, not present in normal plasma, was identified as proalbumin by immunological methods. It was indistinguishable from the molecule normally present in hepatocytes as judged by electrophoretic mobility, limited susceptibility to tryptic digestion, and its inability to bind labeled Ni. We suggest that this release of proalbumin is related to the concurrent presence of both hepatitis B and delta virus in some of the infected hepatocytes.

Adult↗
PubMed1985

Pst I polymorphism of the antithrombin III gene in a French population.

Pst I endonuclease fragment length polymorphism of the antithrombin III probe was studied in a French population. Among 25 subjects tested, 15 were found heterozygous at the Pst I site, so that this polymorphism might serve as a useful markers of antithrombin III gene in families with antithrombin III deficiency.

Antithrombin III↗
PubMed1984

Klebsiella plasmid K21 is not involved in the aetiology of ankylosing spondylitis.

The possibility that a plasmid carried by Klebsiella pneumoniae plays a role in the pathogenesis of ankylosing spondylitis was explored. K. pneumoniae K21 contains a congruent to 25-kb plasmid, but this plasmid is not present in lymphocyte DNAs of ankylosing spondylitis HLA-B27 patients, as demonstrated by molecular hybridization experiments.

Blotting, Southern↗
PubMed1982

[High molecular-weight polymers in human albumin solutions. Quantitative determination by polyacrylamide gradient electrophoresis].

Isolated albumin almost always contains polymerized forms which appear during preparation and storage of the protein. The proportion of polymerized forms reflects the degree of stability of the solution. The quantitative estimation of the polymers is usually performed by gel chromatography. In this work, the high resolution power of polyacrylamide gradient gel electrophoresis (Gradient PAGE) was used to separate the polymers present in the preparations of human serum albumin. The analysis of the different peaks obtained by gel chromatography allows to conclude that peak 1 contains aggregates and high polymers, peak 2 trimer and dimer and peak 3 the monomer of albumin. The aggregates of the peak 1 can be dissociated by SDS and correspond, in gradient PAGE, to the high polymers. By using gradient PAGE in the presence of SDS under the conditions described in this paper, it is possible to estimate the proportion of high polymers and aggregates present in albumin preparations. These results are similar to those obtained by chromatography followed by a protein assay but noticeably inferior to those resulting from measurements performed by absorbance at 280 nm.

Chromatography, Gel↗
PubMedDate not supplied

ABO-blood-group-related idiotypic network: mimicry of oligosaccharide epitope by rabbit antiidiotypic antibodies to murine monoclonal anti-A antibody.

The idiotypy of antibodies (Ab) specific for oligosaccharide determinants of blood groups of the human ABO system was studied through a cascade. Xenogenic antiidiotypic Ab (Ab2) raised in rabbits to the murine monoclonal anti-A61 (Ab1) were screened for reactivity with various anti-ABH Ab. Three anti-A and three anti-A,B monoclonal antibodies (mAb) which were developed in the same mouse strain as that producing Ab1, as well as a human polyclonal anti-A, were found to share cross-reactive idiotopes (CRI) with Ab1. CRI on murine mAb could be due to a Biozzi recurrent Id on anti-A Ab reacting with anti-Id "à la Oudin", while CRI on human anti-A Ab suggested the presence of paratope-induced anti-Id. Inhibition by Ab2 of haemagglutination of A, B or O human red blood cells by many murine anti-ABH mAb, and by polyclonal or monoclonal human anti-A, strongly supported the occurrence of anti-Id mimicking ABH epitopes belonging to type 2 determinants carried by human erythrocytes. Furthermore, a rabbit immunized with Ab2 produced a potent Ab3 response characterized by anti-H-type-2 specificity. Altogether, these results are consistent with the first successful production of anti-Id Ab that mimics the tridimensional shape of a well defined and strictly carbohydrate epitope, eliciting a haemagglutinating Ab3.

ABO Blood-Group System↗
PubMedDate not supplied

[Rare phenotypes of alpha-1 antitrypsin: study of a case of the M1X variant].

Alpha-1 antitrypsin is the major component responsible for the normal alpha 1 band in human serum. Some genetic variants giving double alpha-1 band, may be associated with pathological process. In the course of a systematic screening of blood donors a double-band alpha-1 pattern was observed in a serum, due to the heterozygous expression of a genetic variant of the PI system. A possible clinical significance of the variant was investigated by characterizing it. The very rare allotype PI*X was identified and its frequency in the population of french blood donors was estimated around to one for 10,000.

Adult↗