Sequential inhibition by progesterone: Effects on sexual receptivity and associated changes in brain cytosol progestin binding in the female rat

The purpose of this study was to examine the role of cytosol progestin receptors (CPRs) in the activation of mating behavior in the estrogen (E₂) stimulated, ovariectomized rat, following the administration of a dose of progesterone (P; 2.5 mg) which is sufficiently large to inhibit the re-induction of sexual receptivity by subsequent P (‘sequential inhibition’). In order to control for competition by unlabeled P in our binding studies, aliquots of cytosol supernatants were passed through LH-20 columns prior to in vitro incubation with the radioactive ligand, [^{staggered 3}H]R5020 (double column assay).Three days following E₂ priming, all animals used in biochemical studies received either P (2.5 mg) or vehicle injections (propylene glycol; PG) 24, 28 or 72 h prior to the administration of P (0.5 mg). When P (0.5 mg) was given 24 h after P or PG treatment, animals which had received P previously showed significantly decreased lordosis quotients (LQ), lordosis quality (LS) and proceptivity scores relative to PG controls (‘sequential inhibition’). The inhibitory effects of previous P (2.5 mg) were transient, and were not observed if P (0.5 mg) was delayed until 72 h after P or PG treatment.Three days following E₂ priming, all animals used in biochemical studies received either P (2.5 mg) or PG. When we did not control for competition by unlabeled P, [^{staggered 3}H]R5020 binding in the cortex, mediobasal hypothalamus-preoptic area (MBH-POA) and pituitary was decreased by 60%, 3 h after 2.5 mg P. When we used the double column assay to remove P in the tissue, [^{staggered 3}H]R5020 binding in all tissues was decreased by 20% at 3 h after 2.5 mg P. By 24 h, after 2.5 mg P, the competitive effect of tissue P on [^{staggered 3}H]R5020 binding was not measurable; and cytosol progestin receptor (CPR) levels were less than or equal to those seen at 3 h. By 72 h after 2.5 mg P, CPRs had returned to control levels in all tissues.Our data suggest: (1) the double column assay is necessary to estimate CPR levels when P is present in the tissue; (2) when one controls for competition by P, CPR depletion 3 h after P is measurable but not extensive; depletion occurs in tissues in which CPRs are induced by E₂ (pituitary, MBH-POA), as well in cerebral cortex, where CPR levels are not included by E₂; (3) at 24 h, CPR levels are less than or equal to those seen at 3 h in all tissues; this may be the result of the initial depletion associated with nuclear translocation, or it may indicate that P regulates its own receptor concentration in the central nervous system (down-regulation); and (4) after a large dose of P (2.5 mg), reduced CPR levels correlated with P's reduced ability to facilitate sexual receptivity.     

Comparative Clinical Study of Two Hypnotic Drugs

The comparative sleep-inducing and sleep-sustaining effects of glutethimide, 0.5 g., and ethchlorvynol, 0.5 g., were studied in 20 patients hospitalized for a considerable time (average: 21 years; minimum nine years and maximum 32 years) and not receiving psychotropic agents. Assessment of sleep and para-sleep parameters (pre-sleep tension; frequency of awakening at night; post-sleep activity) revealed that patients fell asleep faster (P>.001) and slept for a longer time with ethchlorvynol than with glutethimide.     

Unsuspected duplex ureters.

Three cases of unsuspected duplex ureters are presented. It is suggested that nonvisualizing upper pole segments should be suspected whenever a duplication occurs on the contralateral side regardless of the radiographic appearance.     

Invasive Exserohilum sinusitis in a patient with aplastic anemia

A case of acute, invasive, sinusitis caused by the dematiaceous mold Exserohilum rostratum is presented. Herein we examine the subtypes of fungal sinusitis and briefly discuss some characteristics, pathologic and microbiologic differential diagnoses and management strategies of Exserohilum sinus infection in an immunocompromised patient.     

Ethics roundtable debate: Child with severe brain damage and an underlying brain tumour

A young person presents with a highly malignant brain tumour with hemiparesis and limited prognosis after resection. She then suffers an iatrogenic cardiac and respiratory arrest that results in profound anoxic encephalopathy. A difference in opinion between the treatment team and the parent is based on a question of futile therapy. Opinions from five intensivists from around the world explore the differences in ethical and legal issues. A Physician-ethicist comments on the various approaches.     

Disease and nonbattle injury patterns: afloat data from the U.S. Fifth Fleet (2000-2001)

Disease and nonbattle injury (DNBI) patterns were analyzed for reports from the Commander Fifth Fleet for 2000-2001 covering 217,972 person-weeks. The overall DNBI rate was 4.38 visits per 100 person-weeks with the largest subcategory being "other medical/surgical" conditions (1.36 visits/100 person-weeks and over 30% of the initial patient visits). This was followed by dermatological (0.89 visits/100 person-weeks) and respiratory conditions (0.65 visits/100 person-weeks). Collapsing total injuries would have created the third largest incidence category. The mean DNBI rate for cruisers/destroyers/ frigates (4.23 visits/100 person-weeks; SD, 2.64 visits) was not significantly different from aircraft carriers (4.76 visits/100 person-weeks; SD, 1.60, t(df = 207) = -0.91, p = 0.363) but was statistically different from supply ships (8.93 visits/100 person-weeks; SD, 2.44, t(df = 191) = -6.23, p = 0.000) and amphibious support ships (8.07 visits/100 person-weeks; SD, 3.99, t(df = 190) = -4.72, p = 0.000). These results are compared with historical data from land-based units, and the limitations in shipboard DNBI reporting are discussed.