Biomedical subjects

R Duclos

Publications and source records attributed to R Duclos.

4 recordsLinked to original sources

PubMed1991

Comparison of oral bioavailability of two dosage-forms of progesterone in women.

For poorly water soluble drugs, the dissolution process in biological fluids the rate limiting step in absorption. However, the utilization of some galenic processes such as solid dispersions (SD) leads to an improvement in quality and intensity of the drug gastro-intestinal absorption. In a previous work, the in vitro studies of the dissolution curves of both the pure micronized progesterone (MP) and the progesterone-PEG 6000 SD revealed marked increases in the progesterone dissolution rates for all the SD investigated compared to the pure MP. The aim of this work was to investigate the in vitro results after oral administration of the two pharmaceutical forms to menopaused volunteer women.

Administration, Oral↗

PubMed1988

Increase of uterine motility and simultaneous decrease of progesterone concentrations in the rat after bilateral ovariectomy at mid-pregnancy.

Comparison of uterine activities recorded during the control period to those obtained during the two recording periods after ovariectomy (0-30 min and 30-60 min) showed an increase of the amplitude of uterine contractions (P less than 0.005) and a decrease of the interval between two successive uterine contractions (P less than 0.005) and the delay of electrical activities (P less than 0.005). Progesterone treatment (50 mg/kg i.m.) of ovariectomized rats prevented the abrupt fall in plasma progesterone concentrations, measured by RIA, which in turn inhibited the increase of uterine mechanical and electrical activities. A close relation between the increase of myometrial activity and the decrease of progesterone concentrations after ovariectomy is suggested. The activation of the myometrium would be principally induced by the fall of progesterone or by the variation of the oestrogen/progesterone ratio; these changes in sexual steroid hormones would augment the uterine sensitivity to physiological stimuli or modify the activity of other factors involved in the regulation of the myometrium.

Animals↗

PubMed1988

Variation of myometrial activities and steroid sexual hormones following bilateral ovariectomy in the rat at midpregnancy.

The effects of bilateral ovariectomy on uterine motility and levels of progesterone, oestradiol, cAMP, adrenaline and PGF2 alpha were studied in the rat at midpregnancy. Animals were randomly divided into two groups, at least 15 rats in each, sham-operated serving as controls and ovariectomized. The spontaneous uterine mechanical activity of Wistar rats was recorded isometrically and the electrical activities were recorded simultaneously by two bipolar electrodes. Within 30 minutes of ovariectomy a significant increase of the amplitude of uterine contractions was observed and the simultaneity of electrical activity was significantly improved; these effects became more pronounced at 1h post-ovariectomy (p less than 0.005). Plasma progesterone levels decreased by 20% (p less than 0.01) at 30 min and by 50% (p less than 0.001) 1h after ovariectomy, whereas oestrogen levels remained unchanged. Levels of adrenaline, cAMP and PGF2 alpha in the uterine tissue 1h following ovariectomy were affected as follows: adrenaline (p less than 0.05) and cAMP (p less than 0.001) were reduced and PGF2 alpha augmented (p less than 0.05). It appears that variation of the ratio oestrogens/progesterone induces precociously the activation of uterine mobility and exerts an effect on some factors involved in the regulation of the rat myometrium at midpregnancy.

Animals↗

PubMed1986

[Overload histiocytosis in 2 hemodialyzed patients. Possible role of dextran 40].

The authors report two cases of singular overloading histiocytosis, observed in patients treated with regular dialysis and undergoing feverish cachectic disease. The observations of the two patients show a same histiocytosis infiltration of ganglions, liver, muscles, lung, pleura and pericardium, consisting in an accumulation of PAS positive intracytoplasmic substance, refringent at polarisation, microcrystalline on electron microscopy and on ionic analysis. Clinical likeness appears with PVP thesaurismosis but the histochemical findings are different. A favorable issue occurred with corticosteroïd treatment. Nature of PAS positive substance is uncertain. An exogenous origin is undoubted, and some elements call for the responsibility of dextran 40.

Adult↗