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B Genetet

Publications and source records attributed to B Genetet.

At least 19 recordsLinked to original sources
PubMed1992

Interferon production in severe hemophiliacs with and without HIV antibodies.

The interferon (IFN) system, both serum IFN levels and the in vitro IFN production, was investigated in 38 clinically asymptomatic multitransfused hemophiliacs, half positive and half negative for HIV antibodies. In most patients, no circulating IFN was detected; similar levels of IFN-alpha were obtained after peripheral blood mononuclear cell (PBMC) stimulation with Sendai virus both in hemophiliacs and controls, while production of IFN-gamma following stimulation with phytohemagglutin (PHA) was diminished in a large number of patients irrespective of their HIV serology. These data indicate that the deficiency in IFN-gamma generation is not only related to HIV contamination but may be a direct consequence of the chronic antigenic stimulation through Factor VIII concentrates.

HIV Seropositivity↗
PubMed1992

Is there a mechanical factor of haemolysis in patients with positive IgG-type direct antiglobulin test?

In autoimmune haemolytic anaemia, the presence of antibodies on the erythrocyte membrane results in haemolysis through an immune process, but does it not alter the rheological properties of red blood cells (RBC), thus adding a mechanical factor to haemolysis? This study was designed to examine the rheological properties of erythrocytes sensitized with IgG-type antibodies. The study involved 20 patients with anaemia and positive direct antiglobulin test, including 12 with straightforward haemolysis, 10 samples sensitized in vitro, and 20 controls. The following haemorheological parameters were studied: erythrocyte filtration, blood and plasma viscosities, titration of adenosine triphosphate (ATP) and 2-3-DPG, erythrocyte morphology under scanning electron microscopy. The results showed increased erythrocyte rigidity (P less than 0.025) as well as higher blood viscosity compared to controls with similar haematocrit values, and unaltered ATP and 2-3-DPG (consistently with scanning electron microscope observations). These haemorheological disorders were more noticeable in patients with clear-cut haemolysis, and there was a correlation between the increase in erythrocyte rigidity indices and the haemolytic parameters, especially haptoglobin (P less than 0.001). The in vitro study confirmed the results obtained ex vivo. To conclude, the mechanical properties of antibody-coated erythrocytes are impaired, which may promote the immunological mechanism favouring haemolysis in the spleen.

Aged↗
PubMed1992

No major monoclonal lymphocyte population in the thyroid of patients with Graves' disease: study of gene rearrangement by restriction fragment length polymorphism and polymerase chain reaction.

The present study aimed at determining the mono-, oligo-, or polyclonal nature of intrathyroid lymphocytes at the DNA level in patients with Graves' disease. Two techniques were used to seek monoclonal rearrangement in DNA derived from intrathyroidal lymphocytes obtained from six patients. The first was restriction fragment length polymorphism using two specific probes from the B-chain of T-cell receptor and the other from the heavy chain immunoglobulin gene; the second was polymerase chain reaction using a couple of specific primers from the variable and joining regions of heavy chain immunoglobulins. The results for the patients with Graves' disease were compared with those obtained for circulating T-and B-lymphocytes, granulocytes (negative controls), and T- and B-leukemic cells (positive controls). The results with restriction fragment length polymorphism favored a polyclonal origin for the lymphocytes in all cases, since no rearrangement was visualized. The results with polymerase chain reaction were analogous, and the technique was 10 times more sensitive in the detection of rearrangement.

Adult↗
PubMed1991

A human anti-Jkb monoclonal antibody.

Peripheral blood mononuclear cells of an immunized patient were transformed with Epstein-Barr virus and then fused with P3X63Ag8 mouse myeloma cells by polyethylene glycol. After the cloning, a hybridoma cell line secreting specific anti-Jkb monoclonal antibody was isolated. The antibody was produced in supernatant form and tested for its use as a blood grouping reagent.

Animals↗
PubMed1990

Antithyroid drugs and Graves' disease: a prospective randomized evaluation of the efficacy of treatment duration.

A prospective randomized study was performed in patients with hyperthyroid Graves' disease (GD) in order to compare long (18 months) and short term (6 months) antithyroid drug treatment on the remission rate. A therapeutic protocol was offered to all GD patients who had not been treated for this disease previously. All patients studied who followed the protocol were rechecked 2 yr after treatment was withdrawn, or earlier in the case of relapse. Of the patients having undergone long term treatment, 61.8% still were in remission 2 yr after treatment withdrawal, whereas only 41.7% of the patients treated for 6 months were in remission (P less than 0.05). Such findings clearly establish that treatment duration has a direct beneficial incidence on the remission rate. These results were confirmed by the fact that treatment for 18 months resulted in remission in 7 of 15 patients who had previously relapsed after a 6-month course of therapy. This improvement in relation to treatment duration might be due to the immunosuppressive action of carbimazole. No significant difference was observed between relapse and remission groups, regardless of treatment duration, for HLA ABDr, serum T3 and T4, and T3/T4 ratio determined before treatment. Only the thyroid-stimulating antibody levels determined at the time of diagnosis and at the end of treatment were higher in the relapse group, a difference that was relevant only globally, due to value scattering. Furthermore, thyroid-stimulating antibody levels at the end of treatment may indicate remission or, conversely, continuance of the pathological process.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1979

Serum ferritin as a possible marker of the hemochromatosis allele.

To determine whether a correlation exists between the biochemical expression of hemochromatosis and the HLA genotype, we studied 174 family members of 32 persons with the disease. Persons who shared both HLA haplotypes with the proband (and presumably having two hemochromatosis alleles) differed significantly from those who shared only one haplotype (and presumably having one hemochromatosis allele) in terms of serum iron (P less than 0.001 for both sexes), unsaturated iron-binding capacity (P less than 0.01 for female and P less than 0.0001 for male subjects) and serum ferritin (P less than 0.0001 for female and P less than 0.00001 for male subjects). The only significant difference between relatives having one hemochromatosis allele and age and sex-matched controls was related to serum ferritin values in male subjects (P less than 0.05, despite considerable overlap). In our hands, serum ferritin was the best indicator of disordered iron metabolism and was elevated among most homozygous but among few heterozygous family members.

Adolescent↗
PubMed1979

[Demonstration by iron overloading study and HLA genotyping of recessive transmission of idiopathic haemochromatosis in two pseudodominant pedigrees (author's transl)].

We studied iron overloading and HLA genotype in two families with overt forms of idiopathic haemochromatosis in two successive generations. In each family the spouse of the patient with overt haemochromatosis in the first generation had clinical and laboratory signs of moderate iron overload and a HLA haplotype A3, B14 and A3, B7 respectively--which is frequently associated with the haemochromatosis gene. This specific HLA haplotype had been transmitted to the second generation patient with overt disease, which thus could be considered as having received a haemochromatosis gene from each parent. Although the finding of cases of overt disease in successive generation firstly suggests a dominant transmission the genetical analysis of these families lead to further strong argument in favour of recessive inheritance of idiopathic haemochromatosis.

Adolescent↗
PubMed1979

HLA determinants in idiopathic hemochromatosis.

HLA-A and B antigens were defined in 154 unrelated idiopathic hemochromatosis patients. The study confirmed the highly significant positive association with HLA antigens A3 (corrected P less than 10(-10)) and B14 (corrected P less than 10(-9)). HLA-DR typing showed increased frequency of the specificity DRw6, which was frequently associated with the phenotype A3, B14 and antigen B14, suggesting linkage disequilibrium. This was borne out by PLT data.

Epitopes↗
PubMed1979

HLA antigens in chronic alcoholic pancreatitis.

HLA typing was performed in 90 unrelated patients with chronic alcohol-associated pancreatitis. Compared with 523 healthy controls, an increased frequency was found for the HLA-B series antigen, B40 (Pless than 0.00041, corrected P less than 0.011). The increase was slightly more pronounced in patients without pancreatic calcifications than in those with calcifications. Factors such as alcohol consumption, age of disease onset and the presence of diabetes did not affect antigen frequency distribution.

Adult↗
PubMed1979

Role of blood transfusions and pregnancies in kidney transplantation.

A retrospective study in 71 cadaver renal transplant patients showed a significantly better 2-year graft survival rate (62%) in patients who received pretransplant transfusions or who were parous than in nontransfused patients or patients who have not been pregnant (29%). The beneficial influence of blood transfusion and of pregnancy is thus confirmed. An additive effect of blood transfuion and pregnancy is suggested by the results of this study.

Blood Transfusion↗
PubMed1979

[Relations of HLA A2, A3, B12 antigens, and A2-B12 supposed haplotype association, with latent herpes virus infection in patients with chronic renal disease (author's transl)].

Comparison of 105 patients suffering of chronical renal failure with 108 normal persons showed that, in the former group, a relation could be established between HLA A2, A3, and B12 histocompatibility antigens as well as haplotype association A2-B12, and chronic infection by herpes virus. The high number of herpes virus observed in patient group bearing the BW 35 antigen was discussed.

Adolescent↗
PubMed1978

The gene(s) controlling the synthesis of C1 esterase inhibitor is not linked to the genes of the HLA system and is not on the 6th chromosome.

Certain genes of the complement system are carried by the 6th chromosome and are sometimes linked to particular genes of the HLA system. This study shows that in 15 patients suffering from hereditary angioneurotic oedema the gene(s) controlling the synthesis of C1 esterase inhibitor is not linked to the genes HLA-A or B and is not on the 6th chromosome.

Angioedema↗