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D Fries

Publications and source records attributed to D Fries.

At least 163 records · Page 9Linked to original sources
PubMed1981

Immunological studies in human ageing. I. In vitro functions of T cells and polymorphs.

T-cells were investigated by the E rosette assay, PHA stimulation, allogeneic MLC and CML responses, in a group of 100 healthy aged people over 70 years old, and compared to young control individuals less than 45 years old. No major difference was found between the two groups, except for PHA stimulation which was significantly reduced in old individuals when low mitogen concentration was used. These observations suggest that only some T cells subsets are affected by ageing, without modification of the total T lymphocyte number. Contrarily, the phagocytic activities of polymorphonuclear cells assessed in a group of 38 aged people were dramatically decreased, using either the NBT test or a direct phagocytosis assay.

Aged↗
PubMed1981

[T lymphocytes functions in mercuric chloride-induced membranous glomerulonephritis in man. Evidence for a defect of presentation of the histocompatibility class II molecules at the cell surface (author's transl)].

Membranous glomerulonephritis (MGN) is one of the well documented manifestations of autoimmunity during chronic mercuric chloride (HgCl2) intoxication. We have carried out immunological investigation of the T cell functions in a patient presenting an HgC12-induced MGN. Circulating auto-antibodies and immune complexes were absent from the serum. Lymphocyte transformation with HgCl2 over a wide range of doses (10(-3) to 10(-8) M) was negative. E rosettes, mitogen reactivity, allogeneic reactivity evidenced by a one way mixed lymphocyte culture gave slightly diminished results. These findings contrasted with a severe impairment of the stimulative ability of lymphocytes. This defect might be related to the inability of D, DR products to be exposed at the cell surface and impeding the allogeneic recognition by foreign lymphocytes. This lymphocyte defect in the course of an HgC12 MGN in man would be correlated with lymphocyte abnormalities found in experimental HgC12-treated rats. The results of this study would favour the hypothesis of a direct role of HgC12 on lymphocyte rather than a direct action on glomerular basement membrane.

Adult↗
PubMed1980

Hamster flank organ hydrolase and lipase activity.

The hydrolase and lipase activities of homogenates of the golden Syrian hamster flank organ (sebaceous complex) and skin were studied using synthetic fluorogenic substrates, 4-methylumbelliferone butyrate (4 MUB) or 4-methylumbelliferone palmitate (4 MUP). Homogenates of both flank organ and skin demonstrate a higher level of hydrolase activity (MUB substrate) than lipase activity. Flank organ however is enriched in lipase activity (4 MUP substrate) demonstrating 8 times as much activity as the skin. Systemic androgen treatment of female hamsters significantly stimulates the flank lipase activity while topical estradiol or the antiandrogen flutamide significantly decrease lipase. Testosterone and estradiol have a converse and weaker influence on hydrolase activity suggesting that this activity may be associated with different cell types. These effects do not appear to be direct since these compounds do not inhibit either enzyme in vitro. This data suggests a role for endogenous tissue lipases in the maturation of sebaceous tissue. Tetracycline and retinoic acid inhibit the activity of both enzymes in vitro. Retinoic acid also inhibited both in vivo while tetracycline inhibited only the lipase.

Animals↗
PubMed1979

[Production of O antigens and antibodies during urinary tract infections due to Escherichia coli (author's transl)].

In 138 adults with monomicrobial E. coli urinary tract infections, IgG coated bacteriuria (ACB) are found in 9/10 acute pyelonephritis, 21/24 chronic pyelonephritis, 2/5 acute prostatitis, and in only 6/99 lower UTI. These urinary antibodies are synthetised localy because IgA-S are found in 75%, in the kidney because humoral IgG antibodies are detected in only 40% of the ACB + patients. O6, O18, O22, O75, are the four most frequent O antigens (47,5%) and no difference were found in the distribution of O serotypes according to ACB production or clinical signs. But rough strains are significantly more frequent in pyelonephritis, suggesting a modification of the bacterial wall. The use of ACB test and O serotyping allows a better follow-up of patients, but relapses with ACB- and reinfection with ACB+ show the complexity of the relation host-E. coli.

Acute Disease↗