Pituitary hypoplasia and lactotroph dysfunction in mice deficient for cyclin-dependent kinase-4

The lactotroph undergoes dynamic regulation of cell cycle progression during pregnancy, as well as throughout the development of the pituitary. We recently reported that female mice with targeted disruption of Cdk4, one of the G(1)-regulatory cyclin-dependent kinases, are unable to support embryo implantation because of defective progesterone secretion from the corpus luteum. In this study, we demonstrate that this phenotype is not attributable to a primary defect in the corpus luteum but is a consequence of defective prolactin (PRL) production caused by inappropriate development of the pituitary lactotroph population. Specifically, the pituitary of Cdk4-deficient mice is extremely hypoplastic. Lactotrophs and somatotrophs of prepubertal Cdk4-deficient mice were 80% decreased in number, relative to those in wild-type mice, whereas gonadotrophs were unaffected. Lactotrophs of Cdk4-deficient mice did not proliferate in response to estrogen administration, whereas estrogen could induce the expression of galanin, an estrogen-responsive factor required for lactotroph proliferation. The reduction in lactotroph numbers was reflected by markedly diminished serum PRL levels in both prepubertal and postcoital Cdk4-deficient mice. Administration of PRL, after mating, significantly increased serum progesterone levels and restored implantation in Cdk4-deficient female mice. These observations demonstrate that Cdk4 is required for normal proliferation of the lactotroph population.     

Daily serum follicle-stimulating hormone, luteinizing hormone, and plasma testosterone and androstenedione in hirsute women with polycystic sclerotic ovaries: effects of diethylstilbestrol and norethindrone acetats

Serum follicle-stimulating hormone (FSH), luteinizing hormone (LH), plasma plasma testosterone and androstenedione, were determined daily in 5 women with mild to hirsutism and polycystic sclerotic ovaries, and in 2 normal controls. Blood was sampled daily for 10 days before and 10 days during administration of diethylstilbestrol 3 mg daily or norethindrone acetate 5 mg daily, during Cycle Days 2-12 in controls. FSH was significantly (p = .05 or less) decreased in 4 patients by diethylstilbestrol, and in the vehicle for serum triglyceride, pre-beta lipoprotein, was not significantly elevated in any subjects. Though the mechanism of these pills' effect on serum lipids is not known, although it appeared to increase in 4 patients and 1 control during stimulation. must produce caution in evaluating long-term oral contraceptive administration.     

Testosterone and estradiol concentrations in paired maternal and cord sera and their correlation with the concentration of chorionic gonadotropin.

Testosterone (T) and estradiol (E2) concentrations were determined and correlated with beta human chorionic gonadotropin (beta-HCG) concentrations in 43 paired maternal and cord sera (22 female and 21 male infants). Mean (+/- SD) maternal E2 concentrations were significantly (P less than .005) higher when the sex of the fetus was male than when the sex of the fetus was female (20.6 +/- 3.9 vs 13.5 +/- 3.2 ng/ml). Maternal T concentrations were not significantly different when related to the sex of the fetus (males, 114.8 +/- 60.7 vs females, 113.8 +/- 54.5 ng/100 ml, P greater than .1). Regression analysis did not show a significant correlation between maternal T or E2 concentrations and maternal beta-HCG concentrations. Mean cord serum T and E2 concentrations of male infants were significantly greater than that of female infants (T, 38.8 +/- 8.5 vs 25.8 +/- 7.1 ng/100 ml, P less than .005; E2, 9.1 +/- 3.3 vs 6.6 +/- 2.0 ng/ml, P less than .005). Regression analysis showed a significant (P less than .005) correlation between cord beta-HCG concentrations and E2 concentrations for male infants (r = .7) and female infants (r = .6). A significant correlation between cord beta-HCG concentrations and T concentrations was found for male infants (r = .5; P less than .01) but not for female infants (r = .3; P greater than .05). There was no correlation between maternal and infant E2 concentrations (males, r = .3, P greater than .05; females, r = .3, P greater than .2) or T concentrations (males, r = .02, P greater than 0.4; females, r = .06, P greater than .3). These data (1) confirm the sex difference in cord serum T and E2 concentrations, (2) indicate that the lower beta-HCG concentrations in mothers of male infants are associated with E2 concentrations which are greater than those in mothers of female infants, and (3) are consistent with an influence of beta-HCG on fetal T and E2 secretion.     

Post discharge nausea and vomiting after ambulatory laparoscopy is not reduced by promethazine prophylaxis

PURPOSE: To determine the incidence of post-discharge nausea and vomiting (PDNV) following outpatient laparoscopic procedures in women, and to assess the efficacy of the prophylactic administration of promethazine prior to discharge from hospital. METHODS: Ninety-five healthy women scheduled for ambulatory laparoscopic cholecystectomy or gynecological surgery completed this double blind, placebo controlled study. A standardized fentanyl-propofol-nitrous oxide-isoflurane anesthetic was used, and all patients received 0.5 mg droperidol i.v., intraoperatively. Subjects were randomized to receive 0.6 mg x kg(-1) promethazine or placebo i.m. prior to transfer from the post-anesthetic recovery (PAR) unit. The incidence and severity of nausea, pain, and drowsiness were documented using patient diaries at four time intervals during the first 24 hr postoperatively using four-point self-assessment scales. RESULTS: After discharge home, the overall incidence of nausea was 48%, moderate to severe nausea 30%, vomiting 17% and rescue antiemetic use 28%, with no difference between those receiving saline or promethazine. The need for antiemetics in the PAR was associated with subsequent PDNV, with those requiring PAR antiemetics being four times as likely to vomit after discharge (P = 0.008). CONCLUSION: Despite the prophylactic administration of 0.5 mg droperidol i.v., patients undergoing ambulatory laparoscopic surgery reported a high incidence of nausea after discharge. Patients requiring antiemetics in the PAR were at higher risk for PDNV. The incidence of nausea was not altered by prophylactic administration of 0.6 mg x kg(-1) promethazine i.m. before discharge.     

Polarized secretion of transgene products from salivary glands in vivo

Previously (Kagami et al. Hum. Gene Ther. 1996;7:2177-2184) we have shown that salivary glands are able to secrete a transgene-encoded protein into serum as well as saliva. This result and other published data suggest that salivary glands may be a useful target site for vectors encoding therapeutic proteins for systemic delivery. The aim of the present study was to assess in vivo if transgene-encoded secretory proteins follow distinct, polarized sorting pathways as has been shown to occur "classically" in cell biological studies in vitro. Four first-generation, E1-, type 5 recombinant adenoviruses were used to deliver different transgenes to a rat submandibular cell line in vitro or to rat submandibular glands in vivo. Subsequently, the secretory distribution of the encoded proteins was determined. Luciferase, which has no signal peptide, served as a cell-associated, negative control and was used to correct for any nonspecific secretory protein release from cells. The three remaining transgene products tested, human tissue kallikrein (hK1), human growth hormone (hGH), and human alpha1-antitrypsin (halpha1AT), were predominantly secreted (>96%) in vitro. Most importantly, in vivo, after a parasympathomimetic secretory stimulus, both hK1 and hGH were secreted primarily in an exocrine manner into saliva. Conversely, halpha1AT was predominantly secreted into the bloodstream, i.e., in an endocrine manner. The aggregate results are consistent with the recognition of signals encoded within the transgenes that result in specific patterns of polarized protein secretion from rat submandibular gland cells in vivo.     

Bayesian spatial risk prediction of Schistosoma mansoni infection in western Côte d'Ivoire using a remotely-sensed digital elevation model

An important epidemiologic feature of schistosomiasis is the focal distribution of the disease. Thus, the identification of high-risk communities is an essential first step for targeting interventions in an efficient and cost-effective manner. We used a remotely-sensed digital elevation model (DEM), derived hydrologic features (i.e., stream order, and catchment area), and fitted Bayesian geostatistical models to assess associations between environmental factors and infection with Schistosoma mansoni among more than 4,000 school children from the region of Man in western C?te d'Ivoire. At the unit of the school, we found significant correlations between the infection prevalence of S. mansoni and stream order of the nearest river, water catchment area, and altitude. In conclusion, the use of a freely available 90 m high-resolution DEM, geographic information system applications, and Bayesian spatial modeling facilitates risk prediction for S. mansoni, and is a powerful approach for risk profiling of other neglected tropical diseases that are pervasive in the developing world.     

Highly improved precision of the hypophysectomized female rat body weight gain bioassay for growth hormone by increased frequency of injections, avoidance of antibody formation, and other simple modifications

Mediocre precision has been a frustrating feature of the hypophysectomized female rat body weight gain bioassay for GH, especially human GH (hGH), in the original procedural format of injections once daily, ip, for 10-14 days. Consequently, the principal conditions that influence the bioassay's precision were identified and appropriately modified, by detailed systematic analysis of the daily body weight gain response to treatment with bovine GH (bGH) and hGH. Under identical conditions, the slope and precision of dose-response curves for hGH were markedly inferior to those for bGH. This prompted revision of the injection frequency for hGH to four times daily, sc. Dramatic improvement in slope and precision for hGH resulted, nearly equal to the excellent slope and precision attained for bGH with twice daily injections, sc. In addition, direct and indirect assessment of GH antibody formation pinpointed day 8 as the time of onset of growth-neutralizing antibodies, which are deleterious to precision and accuracy. Accordingly, the injection period was limited to 7 days. A warm environment of 31-32 C to sustain optimal animal health and responsiveness and objective specifications for selection of animals were also used. These modifications, incorporated into standardized procedures (four times daily injections, sc, 7 consecutive days, for hGH; twice daily injections, sc, 7 consecutive days, for bGH) produced a lambda, the index of precision, which hovered on the highly respectable bioassay value of 0.2 consistently and reliably. The demonstration of differing performance characteristics and differing immunogenicities of bGH and hGH in the rat invalidates the use of one as the reference standard for the bioassay of the other, and beclouds the quantitative meaning of all prior data derived in that way.