Jean Franckson

AN IMPROVED METHOD FOR THE DETECTION OF HETEROZYGOSITY OF CONGENITAL VIRILIZING ADRENAL HYPERPLASIA

A modified short ACTH test for the detection of heterozygote carriers of 21‐hydroxylase deficiency (21‐OHD) was applied to twenty‐one controls and fourteen parents of children with 21‐OHD. The following modifications were introduced: (1) Endogenous ACTH was suppressed by dexamethasone administration prior to the test, (2) Plasma 17‐hydroxyprogesterone (17‐OHP), cortisol (F), progesterone (P), corticosterone (B) and Δ4‐ androstenedione (A) were measured, (3) Variables studied were the ratio of plasma increments (A) between precursors and end products, (4) Data were analysed by a step‐wise discriminant analysis. Significant alterations in the metabolic pathway of F, B and A were demonstrated. The discriminant analysis showed that the addition of B pathway data did not improve the discrimination potency of the test performed on F pathway data. The combination of variates which provided the best discrimination was the logarithmic sum of Δ 170HP/ΔF at 15 and 30 min. It led to a 94% correct classification for normals and carriers.

A direct radio-immunoassay for plasma Δ4-androstenedione. Application to children

Abstract A RIA for the estimation of Δ4-androstenedione in human plasma without chromatographie purification is analyzed. Sensitivity, accuracy, precision and specificity are shown to be, at least, equivalent to those of methods involving chromatography.

Glucose Metabolism in the Normal Anesthetized Dog Injected Successively with Anti-insulin Serum and Insulin

Seven fasted, healthy, anesthetized dogs were successively injected at a two-hour interval with guinea pig antiinsulin serum and with insulin. The dose of anti-insulin serum used had a total neutralizing potency of 2 U. insulin per kilogram body weight; the amount of insulin used was sufficient to restore normal blood glucose level. Glucose production was determined by hepatic catheterization; glucose tissue utilization by the study of the disappearance rate of a tracer dose of glucose l-C-14. Anti-insulin serum induced hyperglycemia in five dogs and failed to provoke any change in blood glucose among the two others. This difference of behavior was probably related with differing sensitivity to the same fast. In responders, hyperglycemia was accompanied by an increase in liver glucose output and by a reduction of tissue glucose utilization; insulin, when given in sufficient amount to restore normal blood glucose level, induced a decrease of glucose production and an increase in glucose utilization to basal values. In the nonresponders, together with a slight decrease in glucose utilization, a tendency to reduced glucose production was noticed. The doses of insulin necessary to provoke hypoglycemia were three times more important than those used in the responders. The action of insulin on liver glucose production observed in these acute deficiencies of insulin are discussed in relation to experiments previously carried out on normal dogs.

L'oxydation bismuthique des corticostéroïdes urinaires (fractionnement chromatographique sur colonne)☆

Resume Les auteurs etudient les caracteristiques chromatographiques des 17-cetosteroides obtenus par oxydation bismuthique de la cortisone, du cortisol et de la tetrahydrocortisone, dans un systeme de fractionnement sur colonne derive de la methode de Dingemanse .

Evaluation of a new procedure for isoamylase measurement by selective inhibition

The authors have evaluated a new procedure for the estimation of pancreatic and salivary isoamylase using a new selective inhibitor reagent (Enzamyl Isoamylase, Gödecke), Germany; composition covered by patent No. P 3404876.6). Provided the conditions of the assay presented here are correctly selected, a standard curve is not necessary and the activities of both isoenzymes can be calculated by a simple formula. In view of its rapidity and precision, this new procedure appears to be useful as a screening test. It correlates closely with a reference electrophoretic method.

L'oxydation bismuthique des corticostéroïdes urinaires: application à la mesure de la sécrétion de cortisol par dilution isotopique

Abstract A new method is described for the measurement of cortisol secretion rate by the isotope dilution technique. The main steps of the procedure are a bismuthate oxidation of the urinary metabolites of cortisol, an alumina column chromatography and the determination of the specific activity of the pooled major metabolites of cortisol. This procedure avoids the difficulties encountered in the methods using paper chromatography. For ten normal adult males, cortisol secretion rate was 22.0 mg/24 h with a standard deviation of 3.1 mg. These results are in fair agreement with the data recorded in the literature.

L'oxydation bismuthique des corticostéroïdes urinaires

Abstract The authors described the application to the urines of a method of selective determination of the 17-hydroxysteroids, using enzymic hydrolysis, bismuthate oxidation and column chromatography (17-ketogenic steroids). This procedure allows the simultaneous determination of the excretion rate of the 11-deoxyand 11-oxysteroids. The results obtained in normal subjects and after stimulation and suppression of the adrenal secretion (ACTH, dexamethasone, metopirone and pyrogens) show the practical interest of this method.

Effets d'une hyperglycémie prolongée sur le métabolisme glucidique du chien normal

~7~~~~~~~~~~~~~ (1936), ktudiant le chien normal soumis a des perfusions de longue durke, a rythme variable, a dissocie la notion de rendement de l’action de masse proprement dite et a prouvk que, si la captation augmente proportionnellement a la quantitk perfuske, le pourcentage de produit mktabolisi: a la sixikme heure devient de plus en plus faible lorsqu’on augmente le rythme de perfusion, jusqu’i atteindre une valeur basse

Diabetes Induced in Experimental animals by Insulin antibodies

Untill 1955, surgical removal of the pancreas or selective destruction of the beta-cells by alloxan injection were the commonest methods for producing an insulin deficient state. These procedures were open to criticism for numerous reasons: severe lesions induced in other organs, delayed appearance of the diabetic state, irreversibility of this condition. In fact those procedures studied far more the secondary injuries to the enzyme machinery of the tissues than the direct effects of the insulin deficiency.