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1.
J Emerg Med ; 17(3): 405-12, 1999.
Article in English | MEDLINE | ID: mdl-10338229

ABSTRACT

Much has been written about "abuse" and "overutilization" of Emergency Departments (EDs). We undertook to study, from the patient's perspective, physician and patient factors that influence the patient's decision to seek ED care. The study was designed as a convenience cohort, multi-centre survey, conducted in 13 hospitals in the Greater Toronto Area. In our study group of 948, most ambulatory patients (93%) seeking care in an ED have a primary care physician. From the patient's perspective, most (76%) primary care physicians are not educating their patients about which situations warrant ED care and up to 54% are not informing their patients about which services are offered in the office. As many as 55% of patients presented to the ED because it was more convenient. Only a minority (23%) of patients felt their acuity of illness warranted an ED visit. Primary care physicians need to play a stronger role in educating their patients about the utilization of emergency care and the services offered in the office setting.


Subject(s)
Emergency Service, Hospital/statistics & numerical data , Health Services Misuse/statistics & numerical data , Patient Acceptance of Health Care/statistics & numerical data , Physician-Patient Relations , Adolescent , Adult , Family Practice , Health Services Accessibility/statistics & numerical data , Hospitals, Urban , Humans , Ontario , Surveys and Questionnaires
2.
Brain Res ; 764(1-2): 158-66, 1997 Aug 01.
Article in English | MEDLINE | ID: mdl-9295205

ABSTRACT

The neuroactive steroid, 3a-hydroxy-4-pregnen-20-one (3alphaHP), is a metabolite of progesterone and a precursor of 3alpha-hydroxy-5alpha-pregnan-20-one (5alphaP3alpha; allopregnanolone). In addition to analgesic and anxiolytic effects by interaction with the GABA(A) receptor complex, 3alphaHP regulates pituitary FSH secretion by rapid non-genomic interaction with the Ca2+-driven cell signaling mechanisms. Since gonadectomy and adrenalectomy do not result in elimination of 3alphaHP, and since there is the possibility of paracrine and/or autocrine regulation of FSH release, the capacity of pituitary cells to regulate levels (by synthesis, metabolism, and storage) of 3alphaHP was examined. Anterior pituitaries from random cycling female rats were incubated, either as fragments or as cultured cells, for 1, 4 or 8 h with 3H- or 14C-labeled progesterone. The steroid metabolites were identified by thin-layer chromatography, autoradiography, high pressure liquid chromatography (HPLC), derivatization and GC/MS. Pituitary cells actively converted progesterone to 3alphaHP along with 5alphaP3alpha, 5alpha-pregnane-3,20-dione, 20alpha-hydroxy-5alpha-pregnan-3-one, 3beta-hydroxy-5alpha-pregnan-20-one, 5alpha-pregnane-3alpha(beta), 20alpha-diols, 20alpha-hydroxy-4-pregnen-3-one, and 4-pregnene-3alpha(beta), 20alpha-diols. The results indicate the presence of the following steroidogenic enzymes in anterior pituitary cells: 3alpha-hydroxysteroid oxidoreductase (3alpha-HSO), 20alpha-HSO, 3beta-HSO, and 5alpha-reductase. The activities of 5alpha-reductase and 3alpha-HSO were approximately equal and greatly exceeded those of the other enzymes. After 8 h of incubation with 100 ng progesterone per pituitary, about 20% of the progesterone was metabolized and 3.18 ng of 3alphaHP had been formed. The accumulation of 3alphaHP increased approximately linearly with the time of incubation. Metabolism studies using [1,2,6,7-(3)H]3alphaHP showed that pituitary cells convert about 29% and 8% of the 3alphaHP to progesterone and 5alphaP3alpha, respectively, in 2 h. Specific radioimmunoassays determined 11.6 and 7.5 ng of 3alphaHP per pituitary, respectively, in 25- and 40-day-old non-cycling female rats; these concentrations of 3alphaHP were about 2-3-fold greater than those of progesterone in the same pituitaries. In older (80-100 days old) cycling rats, the levels of 3alphaHP were about 9.4 and 18.6 ng/pituitary at 13.00 h and 22.00 h, respectively, on the day of proestrus, while the concomitant circulating levels were 13.7 and 5.4 ng/ml. The results indicate a marked capacity of rat pituitary cells to synthesize the neuroactive and FSH regulating steroid, 3alphaHP, from progesterone, and in turn to metabolize 3alphaHP to the neurosteroid, allopregnanolone, and to progesterone. The studies suggest cyclic biosynthetic and metabolic pathways for 3alphaHP and other steroids in the pituitary. They also indicate that the regulation of FSH secretion by 3alphaHP may be (in part, or in whole) via paracrine or autocrine mechanisms.


Subject(s)
20-alpha-Dihydroprogesterone/analogs & derivatives , Pituitary Gland/metabolism , 20-alpha-Dihydroprogesterone/biosynthesis , 20-alpha-Dihydroprogesterone/metabolism , Animals , Autoradiography , Chromatography, High Pressure Liquid , Chromatography, Thin Layer , Female , Gas Chromatography-Mass Spectrometry , Pituitary Gland/cytology , Pituitary Gland/enzymology , Radioimmunoassay , Rats , Rats, Sprague-Dawley
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