Biomedical subjects

M Dupuy

Publications and source records attributed to M Dupuy.

6 recordsLinked to original sources

PubMed1992

[Prolactin microadenoma in men. Study of 14 cases].

Macroprolactinomas have been well documented in men over the past several years. By contrast, to the best of our knowledge, there have been no reports of microprolactinomas in men. We describe here 14 cases of microprolactinomas occurring in male patients (14 to 53 years old) and discovered on the basis of endocrine symptoms. Nine patients complained of impotence and/or decreased libido, 8 had gynecomastia with or without galactorrhea, 1 had undergone incomplete puberty. All patients had hyperprolactinemia (225 +/- 65 micrograms/l, mean +/- SEM, N less than 13 micrograms/l); plasma testosterone levels were low in 9 (162 +/- 33 ng/dl, mean +/- SEM; N = 308 - 876 ng/dl), while plasma luteinizing hormone (LH) and follicle-stimulating hormone (FSH) levels and their responses to LH-releasing hormone (LHRH) were normal in all cases. Among the 14 patients, 12 had no hypopituitarism and 2 had only partial corticotrope insufficiency; none had visual disturbances and only one complained of headaches. The sella turcica was normal in size and shape in 2 cases but a double floor and/or a thinner part of the floor was observed in 12. CT scan of MRI demonstrated in all cases an intrasellar microadenoma with a mean size of 7 mm (range, 3 to 10 mm) and no preferential localization. One patient was treated with bromocriptine, while the others underwent surgery via the transsphenoidal route. Immunocytochemistry demonstrated immunoreactive-prolactin (IR-PRL) cells in all the adenomas. Surgery resulted in normalization of plasma PRL in 11 of the 13 patients and in lowering PRL levels in the others 2.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1991

Pituitary enlargement with suprasellar extension in functional hyperprolactinemia due to lactotroph hyperplasia: a pseudotumoral disease.

Beside the well characterized PRL-secreting adenomas, a wide spectrum of functional hyperprolactinemic states exists. We describe here five women, 21-38 yr old, all suspected of having a PRL-secreting adenoma because of a pseudotumoral appearance of the pituitary on computerized tomographic (CT) scan or magnetic resonance imaging (MRI). Four had oligomenorrhea with or without galactorrhea, one had amenorrhea with galactorrhea, and two complained of infertility. In the same patient, basal plasma PRL levels were variable on different days, sometimes normal (mean +/- SEM, 11.3 +/- 1.5 micrograms/L), sometimes elevated (49 +/- 7 micrograms/L), but in all cases, a PRL response of large amplitude to TRH (6- to 8-fold increase in the basal value) was observed. Basal plasma levels of estradiol were within luteal phase normal values (0.41 +/- 0.13 pmol/L), while progesterone levels were low (1.92 +/- 0.47 nmol/L). CT scan or MRI showed an intrasellar mass with suprasellar extension, suggesting a tumoral process. However, the signal intensity was homogeneous, and on coronal views, the suprasellar extension was pyramidal and symmetrical, and the pituitary stalk was always in the midline. The five patients were operated on by the transsphenoidal route, but no adenoma was found. Surgical biopsies were taken in four cases, and lactotroph hyperplasia, i.e. enlarged cell cords consisting mainly of PRL cells, was found in three of them. One case displayed a continuum between areas of lactotroph hyperplasia and adenomatous PRL cells. We conclude that functional hyperprolactinemia may mimic on CT scan or MRI a PRL-secreting adenoma.

Adult↗

PubMed1991

[Study of loosening and wear of total hip prosthesis. Apropos of a series followed-up over 10 years].

After reviewing 30 cases of patients having had a total hip arthroplasty by the Charnley's technique between 1970 and 1978, the authors study the radiographic parameters of the cup and of the femoral stem, using geometric buildings described by Sutherland. On the acetabulum, the inclinaition angle, the medialisation and the wear of the cup were calculated. The varisation of the stem and its migration were looked for on the femur. The presence of a radiolucent line, prosthesis--bone or cement--bone and the importance of peri-articular calcifications, was also noted. The verticalisation of the cup and its anteversion were a pejorative factor. The medialisation was disquieting only if it was associated with a verticalisation. The wear more than 2 mm was noted only in 5 cases; the radiolucent line was pejorative only if it was type cement--bone; the type cement--cup, rare, was of less bad prognostic. On the femur, the most failing was the varus of the stem which determined a loosening most often when it was present. The disquieting radiolucent line was always type cement--bone and was always associated with a bicortical reaction showing a mobility of the stem. In a last part, the authors studied the wear of expanted cups in polyethylene which was different of the fluage. A distinction between the theoretical wear and the clinical wear was made. Photographs in scanning electron microscopy which permit to describe the different types of wear are presented.

Adult↗

PubMed1979

[Selective diffusion and osmosis: application to the problem of the functioning of the nephron].

In this article, we propose a new hypothesis concerning biological semipermeable membranes, the walls of vessels or tubules of the human organism. As regards the properties of diffusion of the membranes, this hypothesis includes the phenomena of active and passive transport; as far as the properties of diffusion and osmosis are concerned, it takes into account the orientation of the phenomena, which explains its name: hypothesis of selectivity. By applying this theory to the problem of the transport of salts and urea in the nephrons, we demonstrate that this property is a necessary and sufficient condition to explain the part and working of the functional unit of the kidney, i.e., the nephron, and to validate its operating model, subject of our study. No contradiction has appeared within the present experimental results.

Biological Transport↗

PubMed1979

[Model of the function of the nephron].

After a short review of the functional anatomy of the kidney, we express the usual hypotheses about the phenomena of reabsorption and filtration in the loop of Henle and the collecting duct. Starting from these hypotheses and the laws of biophysics, we formulate the equations of the model. This model accounts for the great increase in concentration of electrolyte and urea in the loop of Henle, the collecting duct and the interstitium, as we "go down" from the outer medullary area towards the inner areas, the active transportation of sodium in the loop of Henle being limited to the thick ascending limb.

Absorption↗

PubMedDate not supplied

Computer-assisted patient-care management.

A computer-assisted patient-care management system is currently operating in two patient-care units as part of a pilot project at the Hôpital Cardiologique, a member institution of the Hospices Civils de Lyon. The system includes the management of administrative records (notice of admission set to the patient-care unit, appointment for admission sent to the patient, notice of admission set to the physician requesting hospitalization, admissions and discharges, patient census) and of patient-care records (orders, examinations, laboratory tests, medications, injections and treatments, a summary list or orders to be carried out during the day, labels for laboratory specimens and requistions for the tests and examinations to be performed); and the medical management of the patient (clinical summary of patient status at admission, results of tests and examinations, summary of hospitalization, data for research and statistics). Computerization was begun in 1977, following the implementation of individualized patient-care records in 1976. The system will be evaluated in 1978 and extended to the remainder of the hospital (18 patient-care units) by the end of 1979.

Computers↗