Biomedical subjects
H Zouaghi
Publications and source records attributed to H Zouaghi.
[Familial distal tubular acidosis].
This study concerned a Tunisian family of 52 members. We have looked for distal tubular acidosis (D.T.A.) after we had discovered that 2 members of this family suffered from nephrocalcinosis with D.T.A. Twenty six of our patients (group I) suffered from D.T.A., 17 from confirmed metabolic acidosis with low urinary pH (5.22 +/- 0.25). Patients of latest groups may present a D.T.A. with intact capacity to lower urinary pH. Our literature review revealed 27 families composed of 228 patients.
High-affinity binding of testosterone in serum from normal developing chick embryos and during the graft-versus-host reaction.
The sera of developing chicken embryos contain high-affinity, low-capacity protein binding sites for testosterone. The affinities remain constant throughout development, with mean values for the association constants of approx. 3.6 X 10(8) M-1 at 25 degrees C, whereas the concentration of sites varies markedly as a function of age: from approx. 2 nmol/g serum proteins in 11-day embryos, it rises to a peak of approx. 5-8 nmol at 14-16 days, then drops to approx. 2.6 nmol at 18 days and only 0.8-1 nmol in adults. Testosterone binding is inhibited by corticosterone, progesterone and dihydrotestosterone, and is little affected by estradiol. The testosterone and corticosterone binding properties of chicken sera show close similarities: parallel ontogenic patterns; constant ratios, throughout development, of the equilibrium binding parameters of the two steroids; mutual binding inhibition. The evidence strongly suggests that the two activities are associated, at least in part, with a common protein carrier(s). In growing embryos which undergo a graft-versus-host reaction, elicited by the graft of adult spleen tissue at 9 days of age, the testosterone and corticosterone binding activities are significantly decreased. This decrease is due to a fall in the number of sites, whereas association constants are not affected. This is the first high-affinity, saturable, testosterone-binding property to be described in an embryonic serum.
Total and unbound cortisol-, progesterone-, oestrone- and transcortin-binding activities in sera from patients with myocardial infarction: evidence for differential responses of good and bad prognostic cases.
Day-of-admission sera from myocardial infarction patients (MI) and patients with cardiopathies other than MI (non-MI) were analysed for total and unbound cortisol (F), progesterone (P4), oestrone (E1), and corticosteroid binding activities (CBG). The MI who survived (n = 28) showed high increases of F, P4 and E1 compared to healthy controls. By contrast, the MI who died within 10 days of admission (n = 6) had unchanged F and less increased P4 and E1 than survivors. The non-MI (n = 6) had higher F and E1 than controls but normal P4. The unbound steroids were increased in all patients: however, the MI who died showed much smaller rises than survivors (P less than 0.001 for unbound F and E1 increases in survivors vs. deceased). The CBG activity was in all MI lower than in normals (P less than 0.001) but unchanged in non-MI. These results are discussed in terms of the potential significance of unbound plasma steroids as predictors of MI severity.
Serum inflammatory responses of transcortin binding activities and of total and free corticosterone and progesterone levels in developing rats: a kinetic approach.
The kinetics of the inflammatory responses of 5 serum parameters involved in specific protein-hormone interactions were studied, namely: transcortin (CBG) binding activities; total corticosterone (B), main ligand of CBG; unbound corticosterone (free B); total progesterone (P4), main competitor of B for binding on CBG; and the free P4. The studies were performed in developing animals, i.e. on rats given a single turpentine injection at 1, 10, 21 or 90 days of post-natal age. The responses showed similar trends at all ages, but age-dependent differences in kinetics and reactivities. Common characteristics were 3-5-fold increases of the hormone parameters as soon as 4-8 h after the injection, and 2-3-fold decreases in CBG activities. A remarkable age-dependent difference was the contrast of early CBG decrease in adults (4 h after turpentine) to the delayed occurrence of this reaction in immatures (8-24 h after turpentine). On the other hand, the increase of free B lasted for 72 h in neonates, but only 40 h in rats treated at 21 or 90 days. Age-dependent characteristics were seen also in reactivities: the peak increases in the hormone levels were highest in the young, while the peak decreases of CBG were most marked in the mature animals. The results suggest that the regulatory mechanisms governing the mutual effects of hormonal activities and CBG synthesis might depend on the stage of development.
[Calendula arvensis L. Impact of saponins on toxicity, hemolytic effect, and anti-inflammatory activity].
The study of the chemical composition of Calendula arvensis var. eu arvensis Maire reveals the presence of saponins. These saponins confer a haemolytic property on the plant. In our work we have, first determined the saponin responsible for the haemolytic property; and then we have studied the impact of the saponins on the acute toxicity and the anti-inflammatory activity induced by carrhageenin oedema.