Kallman's syndrome: effect of repeated stimulation of pituitary-gonadal axis with LH-RH.

The relative roles of the central nervous system and pituitary in the pathogenesis of olfactory gonadal dysplasia has been the subject of much speculation. Repeated stimulation of the pituitary gonadal axis with LH-RH provoked a moderate release of gonadotropins, insufficient however, to stimulate gonadal incretory function. This study supports the evidence that a hypothalamic defect is the basis for Kallman's syndrome.     

Immunodetection of a human chorionic gonadotropin-like substance in human sperm.

The presence of a human chorionic gonadotropin (hCG)-like substance in human spermatozoa is reported. A highly sensitive immunocytochemical procedure was utilized (double-antibody immunofluorescence technique). Rabbit anti-hCG or rabbit anti-hCG beta-subunit was used as the first antibody. A positive fluorescence reaction was found in all human specimens analyzed and in positive controls (choriocarcinoma cells). No fluorescence was detected in other species studied (sheep, pig, goat, horse, bull, and guinea pig), nor in the negative controls. These findings open a new research area on the physiologic role of this hCG-like substance in human reproduction.     

Precoital single doses of delta9-tetrahydrocannabinol block ovulation in the rabbit.

delta9-Tetrahydrocannabinol (delta9-THC) inhibits pituitary gonadotropin secretion in castrated rhesus monkeys. Also, delta9-THC blocks the ovulatory reflux in rabbits. We report now the dose-response relationship of precoital single doses of delta9-THC on luteinizing hormone (LH) release and ovulation in the rabbit. Forty-five female rabbits in estrous were divided into nine groups of five animals. Groups 1 to 5 received a single intramuscular dose of delta9-THC (5,2.5, 1.25, 0.612, and 0.306 mg/kg, respectively) 2 hours before mating; animals of group 6 received vehicle only. In animals of groups 7 and 8 ovulation was induced with 100 IU of human chorionic gonadotropic (hCG), given intravenously 2 hours after the administration of delta9-THC (5 mg/kg) or vehicle. Rabbit luteinizing hormone (rLH) was measured in plasma 90 to 120 minutes after coitus or hCG administration. After the injection of 5 mg of delta9-THC, luteinizing hormone-releasing factor (LH-RF) (20 microgram intravenously) was administered to the animals of group 9. All animals of groups 6, 7, and 8 ovulated. A dose-response curve was observed in the animals treated with delta9-THC and natural mating. Whereas none of the animals treated with 5 or 2.5 mg/kg ovulated, one of the group treated with 1.25 mg/kg, two of the group treated with 0.612 mg/kg, and all treated with 0.312 mg/kg ovulated. Ovulations correlated with postcoital levels of rLH. All animals of group 9 ovulated, indicating that the site of action of delta9-THC is suprapituitary, probably hypothalamic.     

Intrasellar subarachnoid herniation or empty sella associated with galactorrhea

Eight of 115 patients with empty sella had concurrent galactorrhea. All 8 patients had abnormal sellae, and the diagnosis of empty sella was made by polytome pneumoencephalography. There were no obvious endocrine dysfunctions, but 2 patients had elevated prolactin levels. One mechanism for production of galactorrhea may involve compression of the hypothalamus and/or pituitary stalk; this was suggested by most of our observations. There may be a coincidental association of empty sella with galactorrhea, and this association is probably more common than previously noted. Evaluation of patients with galactorrhea and abnormal sellae by polytome pneumoencephalography is emphasized.     

In vitro transformation of mouse mammary epithelial cells grown serum-free inside collagen gels

Mammary epithelial cells from 4-month-old virgin BALB/c mice were cultured inside collagen gels in the following serum-free media: Dulbecco's modified Eagle's medium:Hams's F-12 (1:1) supplemented with: insulin (10 micrograms/ml), bovine serum albumin (5 mg/ml), and epidermal growth factor (5 ng/ml); insulin, bovine serum albumin, progesterone (0.05 microgram/ml), and prolactin (1 microgram/ml); insulin, bovine serum albumin, progesterone, prolactin, and linoleic acid (10 micrograms/ml). Cells proliferated in all these media. The cells were treated with 0.01 micrograms/ml of 7,12-dimethylbenz(a)anthracene or 100 micrograms/ml of N-nitroso-N-methylurea on day 3 of culture and, subsequently, at 1-week intervals for 3-6 weeks. Tetradecanoylphorbol acetate (0.1 micrograms/ml) was added to selected cultures. The cultures were maintained for up to 9 weeks; the cells were then removed from the collagen gels, placed in monolayer culture for 2 days, and removed from monolayer culture, and 5 X 10(5) cells were transplanted to each of the gland-free mammary fat pads of 3-week-old female mice. Approximately 10 weeks after transplantation, the transplanted mammary fat pads were examined for outgrowths. Cells that were not treated with carcinogen and cultured for up to 9 weeks in different serum-free media and transplanted to the gland-free mammary fat pad produced only ductal outgrowths similar in morphology to the ducts of the virgin host's mammary glands. Six treatments with 7,12-dimethylbenz(a)anthracene, of cells grown in the presence of epidermal growth factor, induced 31% spindle cell tumors, 17% ductal hyperplasias, and 5% lobuloalveolar hyperplasias. Cells that were grown in epidermal growth factor and treated three times with N-nitroso-N-methylurea produced 23% ductal hyperplasias and 17% lobuloalveolar hyperplasias. Cells grown in the presence of progesterone and prolactin and treated three times with 7,12-dimethylbenz(a)anthracene produced up to 23% lobuloalveolar hyperplasias and 12% ductal hyperplasias. Three treatments with N-nitroso-N-methylurea of cells grown in progesterone- and prolactin-containing media produced a maximum of 50% lobuloalveolar hyperplasias and 33% ductal hyperplasias. The lobuloalveolar hyperplasias have the characteristics of the precancerous hyperplastic alveolar nodules found in mouse mammary tumorigenesis. The in vitro carcinogen-induced lobuloalveolar hyperplasias were transplantable, maintained their lobuloalveolar morphology in virgin hosts, and produced carcinomas.     

Perceived barriers to the regionalization of adult critical care in the United States: a qualitative preliminary study

Background  

Regionalization of adult critical care services may improve outcomes for critically ill patients. We sought to develop a framework for understanding clinician attitudes toward regionalization and potential barriers to developing a tiered, regionalized system of care in the United States.