Search PubMed⌕ Search

Biomedical subjects

P Dupont

Publications and source records attributed to P Dupont.

At least 91 records · Page 5Linked to original sources
PubMed1994

Many areas in the human brain respond to visual motion.

1. The regions of the human brain responsive to motion were mapped using the H2(15)O position emission tomography (PET) activation technique and compared by viewing a moving random dot pattern with a stationary dot pattern. The stimulus was optimized in dot density and 3 degrees in diameter. 2. In addition to bilateral foci at the border between Brodmann areas 19 and 37, a V1/V2 focus and a focus in the cuneus reported earlier, we observed activations in other visual areas (lower BA 19 and the parieto-occipital fissure) in the cerebellum and in two other, presumed vestibular areas, the posterior bank of lateral sulcus and at the border of BA 2/40. 3. Homologies between monkey and human cortex are discussed.

Adult↗
PubMed1993

Different perceptual tasks performed with the same visual stimulus attribute activate different regions of the human brain: a positron emission tomography study.

To investigate the processing of visual form in human cerebral cortex, we used the PET (positron emission tomography) activation technique to compare the human brain regions that are involved in a visual detection task and two orientation discrimination tasks: the temporal same-different (TSD) task, which includes a short-term memory component, and the identification (ID) task, which is without this component. As a control task we used passive viewing. Stimuli were identical in all four tasks. Subtraction of passive viewing from detection showed that the detection task activates early visual cortical regions (areas 17/18) as well as several motor brain regions, while decreasing activity in several higher order frontal, temporal, and parietal regions. Comparing the ID task to the detection task revealed no further visual cortical activation, while comparison of the TSD task to the detection task revealed an activation of several right visual cortical regions, one of which remained significant after the subtraction of ID from TSD (right area 19). These experiments demonstrate the task dependence of visual processing, even for very closely related tasks, and the localization of the temporal comparison component involved in orientation discrimination in human area 19.

Adult↗
PubMed1992

[The bronchial arteries and their anastomoses with the coronary arteries].

We studied bronchial arteries (BA) and their anastomoses with coronary arteries in 53 adult subjects (30 female and 23 male, mean age 82) and one 2 month old child. Each subject had 1 to 4 BAs, born from an area on the anterior side of the descending aorta measuring less than 2 cm in diameter in 62 percent of the cases and never exceeding 4 cm in the other cases. In 6 cases BAs vascularize the left auricle; more than half of all cases had an anastomose with the coronary arteries: 11 with the right coronary artery and 9 with the left one. These anastomoses preserve the vascularization of the carina after a cardio-pulmonary transplantation. The may have a function of vascular supply in some coronarian patients and the study of associated coronary pathology gives confirmation of it in one fourth of the cases.

Aged↗
PubMed1991

Comparative endocrinological and clinical effects of percutaneous estradiol and oral conjugated estrogens as replacement therapy in menopausal women.

Sixty-three healthy post-menopausal women participated in the study aimed at determining the efficiency of percutaneous administration of estradiol (E2) giving physiological plasma levels of the estrogen to provide an efficient relief of climacteric and urogenital symptoms. Among these women, 31 had previous hysterectomy and were randomly allocated to one of the two estrogen replacement therapies while, similarly, the 32 women having an uterus were randomly divided between two groups who received in addition to estrogens, micronized oral progesterone. As estrogen, women received either E2 by percutaneous administration (Oestrogel) or oral conjugated estrogens (Premarin). With Oestrogel, serum E2 and estrone levels were within those seen during premenopause and showed a ratio close to 1.0. Climacteric symptoms were reduced or eliminated similarly in all groups. No changes was noticed on the concentration of serum angiotensinogen with Oestrogel therapy while a 2.5-fold increase was found in women receiving Premarin. As indicated by the 24-week endometrial biopsy, the progestational response induced by oral progesterone at the dose used was sufficient in twenty out of thirty-two women to cause endometrial atrophy, thus suggesting the need for higher amounts of micronized progesterone in a proportion of women. The present data also indicate that Oestrogel provides efficient relief of climacteric and urogenital symptoms without exerting any detectable effect on hepatic function while maintaining the ratio of serum E2/E1 at the physiological value of 1.0.

Administration, Cutaneous↗
PubMed1991

Changes in plasma lipoprotein and apolipoprotein composition in relation to oral versus percutaneous administration of estrogen alone or in cyclic association with utrogestan in menopausal women.

Sixty-three postmenopausal women were assigned to four treatment groups and received either Premarin or percutaneous 17 beta-estradiol (Oestrogel) alone or in combination with micronized progesterone (Utrogentan). The oral administration of estrogen alone to hysterectomized women resulted in: 1) a significant increase in triglyceride levels in plasma and all major lipoprotein fractions, 2) a significant increase in very low density lipoprotein cholesterol, 3) a significant decrease in low density lipoprotein (LDL) cholesterol but not LDL apo B concentration, 4) a significant increase in all the lipid components of high density lipoprotein (HDL) as well as apo AI, 5) and a significant increase in HDL2 cholesterol. In contrast, percutaneous administration of estrogen to hysterectomized women only increased HDL2 cholesterol and the triglyceride and cholesterol content of the whole HDL fraction. These results suggest that the route of estrogen administration is important in determining effects on lipoprotein metabolism. The same two estrogens were given to women with natural menopause, along with utrogestan, a micronized progesterone. The simultaneous administration of Utrogestan reversed the HDL cholesterol elevating effect of percutaneous estrogen alone, but it had no effect on other plasma lipoproteins. On the other hand, utrogestan in combination with oral estrogen had several potential beneficial effects on plasma lipoproteins. This combination did not negate the effects of oral estrogen alone on HDL, rather it further increased the concentrations of HDL cholesterol and apo AI. It also did not negate the LDL cholesterol lowering effect of oral estrogen alone. Furthermore, utrogestan lowered the magnitude of hypertriglyceridemia induced by oral estrogen alone. These results suggest that Utrogestan has lower potency of androgenic action and has desirable effects when given in cyclic combination with estrogen.

Administration, Cutaneous↗
PubMed1990

Pregnancy in a patient with treated Wilson's disease: a case report.

Pregnancy should have a successful outcome in a patient with treated Wilson's disease if complications are excluded before conception. Chelating treatment must be maintained, although there is some concern about its teratogenicity. We describe the course of pregnancy in a patient followed up in our department.

Adult↗
PubMed1990

Hormonal and biochemical changes during treatment of endometriosis with the luteinizing hormone-releasing hormone (LH-RH) agonist [D-Trp6,des-Gly-NH2(10)]LH-RH ethylamide.

The effect of medical oophorectomy induced by treatment with the luteinizing hormone-releasing hormone (LH-RH) agonist [D-Trp6,des-Gly-NH2(10)]LH-RH ethylamide was studied in 34 patients with laparoscopically proven endometriosis. Tamoxifen was administered during the 1st month of therapy to prevent flare-up of the disease during the estrogen surge. Fifteen women had a decrease of their laparoscopy scores translated into an improvement in the stage of disease, whereas in 12 others, the decrease in their scores was not enough to allow a change of disease stage. The 2nd laparoscopy was not performed in 7 women. Medical oophorectomy, after daily injection of the LH-RH agonist (LH-RH-a), was accompanied by low levels of circulating estradiol. The serum concentration of all delta 4-3-ketosteroids was significantly decreased during medical oophorectomy, whereas the level of circulating delta 5-3 beta-hydroxysteroids was not altered except for pregnenolone. The present data indicate that medical oophorectomy induced by an LH-RH-a in association with tamoxifen is a very efficient and well tolerated therapy in endometriosis.

Adrenal Cortex Hormones↗