Search PubMed⌕ Search

Biomedical subjects

R Jean

Publications and source records attributed to R Jean.

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

HNK-1+ (Leu-7) and other lymphocyte subsets in long-term survivors with renal allotransplants.

At 5 or more years after renal transplantation, 42 patients were studied for their lymphocyte subsets to Leu-1, Leu-2, Leu-3, and Leu-7. It was found that, in this group of patients who ranged from 25 to 60 years of age, there was a significant decrease in the number of T helper cells and a decrease in the absolute level of T lymphocytes, with no significant change in the number of T suppressor cells. On a relative basis, the helper/suppressor ratio was decreased in patients when compared with normal persons. This was due to an increase in the relative numbers of suppressor cells. It was demonstrated that the Leu-7+ subset, which marks the NK population, was significantly elevated, in relative proportion, in peripheral blood when compared with controls. This was not seen on an absolute basis. The age-dependence of the relative numbers of Leu-7+ cells was seen in the normal control population and in the transplant cohort. There was no significant correlation between lymphocyte subset measurements and delayed-type hypersensitivity skin tests in the transplant population. A finding of interest is that 6 of the patients who had been treated for malignant disease during their posttransplant course had significantly higher numbers of Leu-7+ cells on a relative basis. In 5 of these patients, for whom data was available on absolute numbers, there was also a highly significant difference in the absolute numbers of Leu-7+ cells in these treated and surviving allograft recipients. It is speculated that this finding may suggest that an increase in Leu-7+ cells marks posttransplant patients who have a successful outcome following the treatment of malignancy, for which they are at increased risk.

Adult↗
PubMed1985

Two-color immunofluorescence and flow cytometry analysis of lymphocytes in long-term renal allotransplant recipients: identification of a major Leu-7+/Leu-3+ subpopulation.

Using two-color immunofluorescence with fluorescein isothiocyanate (FITC)- and phycoerythrin (PE)-labeled monoclonal antibodies to human lymphocyte antigens and flow cytometry, we studied lymphocyte subsets in 16 long-term renal allotransplant recipients at risk for a mean of 78 +/- 15 mo. The absolute number of Leu-1+, Leu-2a+, and Leu-3a+ lymphocytes is significantly decreased compared with a control population, whereas Leu-7+ and Leu-15+ subsets remain unchanged despite standard chronic immunosuppression (azathioprine and prednisone). Within the Leu-7+ subset, we found various phenotypes. Doubly fluorescent lymphocytes Leu-7+/Leu-1+ and Leu-7+/Leu-2a+ are not significantly different in the transplant population compared with a normal control population. The Leu-7+/Leu-3a+ subpopulation is seen to be significantly elevated, and the Leu-7+/Leu-15+ subpopulation decreases significantly. The relationship between the modification of these two phenotypes within the Leu-7 subset may be an important correlate of decreased NK cell activity in long-term renal allotransplant recipients. These Leu-7+/Leu-3a+ cells, normally less than 1% of peripheral blood lymphocytes, have no known functional activity.

Adult↗
PubMed1984

Specific 5 alpha-dihydrotestosterone receptor and 5 alpha-reductase activity in human amniotic fluid cells.

A macromolecular component which specifically binds tritium-labeled-dihydrotestosterone is present in cultured amniotic fluid cells. The androgen-binding complex is characterized by a 3.6S sedimentation coefficient, an apparent dissociation constant of 1 nmol/L, a mean binding capacity of 243 +/- 140 fmol/mg of DNA, and a specificity for testosterone and dihydrotestosterone. Similar properties have been reported for the androgen receptor of the fetal genital skin fibroblast, which suggests that the tritium-labeled-dihydrotestosterone-binding component in amniotic fluid cells is the androgen receptor. Amniotic fluid cell monolayers incubated with serum-free medium containing testosterone are able to transform testosterone into dihydrotestosterone. The 5 alpha-reduced product has been characterized by thin-layer chromatography and capillary column gas-liquid chromatography. Androgen receptors and 5 alpha-reductase activity are expressed in amniotic fluid cells. The prenatal diagnosis of 5 alpha-reductase deficiency or complete androgen insensitivity syndrome (testicular feminization) is thus theoretically possible and obviously prenatal testing would be indicated in the family at high risk.

3-Oxo-5-alpha-Steroid 4-Dehydrogenase↗
PubMed1983

[Idiopathic pulmonary hemosiderosis and celiac disease in a child. Case report].

An enteropathy with almost total atrophy of the villi was discovered in a 13-year old girl with idiopathic pulmonary haemosiderosis. Coeliac disease was strongly suspected but could not be proven. This case draws attention to the possible association of an idiopathic pulmonary haemosiderosis with a coeliac disease.

Adolescent↗
PubMed1983

[Pneumoblastoma in children. Apropos of 2 cases].

Pulmonary blastoma is an exceedingly rare primary neoplasm in the paediatric age group. Pre-operative diagnosis is impossible because of its lack of specificity in clinical and radiological signs. The only diagnosis is the histopathological one. It is a malignant tumor capable of metastasis with a poor prognosis. The best method of treatment is still unknown but at the present time, the only survivals are the result of a complete and early surgical excision. The authors report 2 paediatric cases which have been observed at the hospital of Montpellier (France) for a 20 years period. They try to determine why children's pulmonary blastoma is slightly different from the adults one. They ask the question of histogenesis.

Adolescent↗
PubMed1982

[Continuous predetermined insulin infusion in insulin-dependent diabetes mellitus (author's transl)].

At the present, prognosis of insulin-dependent diabetes depends on it's degenerative complications. Many studies have confirmed that the incidence of severe degenerative complications of early onset parallels the degree of metabolic unbalance. Unfortunately, in many diabetic patients satisfactory metabolic control is difficult to ensure because of the irregular absorption of insulin injected discontinuously in subcutaneous tissues. This is true even under strict diet conditions. Continuous insulin infusion at a predetermined dosage was therefore suggested. Data on basic requirements is provided by an artificial pancreas. Satisfactory results have already been reported with intravenous and subcutaneous routes. Intramuscular and intraperitoneal routes are at present under trial. The use of portable pumps facilitates these techniques. The insulin dosage must be correctly determined and adjusted to the patient's diet and activity. In brittle diabetes, these methods can provide, at least temporarily, a satisfactory metabolic balance, and useful data for adjusting further therapy.

Adult↗
PubMed1982

Androgen receptors in cultured human skin fibroblasts.

Human skin may be considered as a target organ for androgens, since events characteristic of androgen action have been described in this tissue, as well as in cultured human skin fibroblasts. The culture of human skin fibroblasts gives the opportunity to work on living cells, under controlled conditions, in a renewable material from a single skin biopsy. Using this method, we showed the presence od DHT-receptors in the human fetus and we studied the ontogenesis of androgen receptors in relation to sexual differentiation. In the neonatal period, the physiological T rise was not concurrent with a variation in sex skin androgen receptors. The evolution of DHT binding during puberty is now under investigation. These data suggest that the androgen receptor is not modulated by plasma androgens. Androgen receptor determination is of value in defining the biochemical defects involved in partial and complete androgen insensitivity syndrome (twenty-six cases in our study). In idiopathic hirsutism, DHT binding is used to detect an eventual local hypersensitivity. Fibroblast cultures have also been shown to be an excellent model for the screening of compounds which might block the expression of androgen action by competing for the androgen receptors. Cultured skin fibroblasts are a valuable model for the study of androgen and antiandrogen action in human skin.

3-Oxo-5-alpha-Steroid 4-Dehydrogenase↗