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J Yvart

Publications and source records attributed to J Yvart.

52 records · Page 3Linked to original sources

[Cad antigen in the French population].

An investigation of Cad phenotypes in the French population had been carried out in 1973, in four Blood Transfusion Centers (Mulhouse, Nancy, Paris, Versailles), B and O red cells were tested with the Dolichos Biflorus lectin. Out of 78.528 donors, 56 were found to have the Cad antigen on their red cells. The mean frequency was 0,07%. Nevertheless, this frequency varied among the four above mentioned Blood Transfusion Centers: the observed differences were probably due to the preparation procedure of the Dolichos biflorus extract. The family investigation permitted the analysis of four families with at least three Cad individuals. The independence of the Cad system and of Auberger, Gc, Hp, C'3, PGM, Pac and ADA was demonstrated. A quantitative agglutination study on these Cad samples using the Dolichos biflorus lectin,and a selected AB serum showed a high variability of the erythrocyte Cad Strength, even within one family. Most Cad samples were found polyagglutinable when a sensitive technique and selected AB sera were used. All adult sera contained an anti-Cad1 antibody, except Cad1 individuals. Although strong Sda reactivity was always found in Cad red cells, the anti-Cad and anti Sda specificities were not identical: this was demonstrated by the absorption and inhibition tests of anti-Cad and anti-Sda reagents absorption and inhibition tests of anti-Cad and anti-Sda reagents with Sda material. From thf Cad red cells, there was no evidence of the existence of separable anti-A1 and anti-Cad agglutinins in the Dolichos biflorus lectin.

Blood Group Antigens↗

Detection of hepatitis B virus DNA in serum by a simple spot hybridization technique: comparison with results for other viral markers.

A simplified spot method for determination in serum of hepatitis B virus DNA (HBV DNA) by molecular hybridization is proposed. For simultaneous testing of 30 serum samples, it reduced to about 1 hr the duration of the steps preceding hybridization proper. The method also greatly reduced the loss of DNA during these steps and allowed more sensitive detection in samples of only 25 or 50 microliters. HBV DNA was determined in 181 serum samples by this method, and the results were pooled with 67 previous determinations by the Southern blot technique. Results for the pool were then compared to those obtained with radioimmunoassay for serological HBV markers. Ninety-six of the 248 samples were HBV DNA positive. Eleven others gave variable or inconclusive results, probably due to low viral particle titers. Seventy-two HBsAg- and HBeAg-positive sera contained HBV DNA, confirming that HBeAg is a marker of active viral replication. Fourteen other HBsAg- and HBeAg-positive sera, obtained from eight patients, were either HBV DNA negative or oscillated between negative and positive, or, again, were weakly positive; serological follow-up in 7 patients showed seroconversion to anti-HBe in 5, 3 of which became HBsAg negative. Eight of the HBsAg-positive sera were negative or borderline for HBeAg but contained HBV DNA and may, therefore, have been infective; seven of these sera had anti-HBe. Six HBsAg-negative sera contained HBV DNA and may also have been infective; five of these exhibited HBV antibodies. These results indicate that molecular hybridization not only provides a more sensitive and direct method for detecting hepatitis B virus in serum but also defines additional serological patterns with predictive or epidemiological value.

DNA, Viral↗

Seroimmunologic classification of chronic hepatitis in 57 children.

A seroimmunologic evaluation of 57 children with chronic hepatitis is presented. Twenty-one patients had chronic persistent hepatitis and 36 had chronic active hepatitis. Serum samples obtained before treatment were tested for HBsAg, anti-HBs, anti-HBc, smooth muscle antibody, and antibody to endoplasmic reticulum. A persistently positive HBsAg was observed in the serum of 18 of the 21 patients with chronic persistent hepatitis. The chronic active hepatitis group was divided into three subgroups according to the presence of hepatitis B-virus markers (7 patients), smooth muscle antibody (10 patients), and endoplasmic reticulum antibody (9 patients). Determination of these markers could be useful for classifying children with chronic hepatitis.

Adolescent↗