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In order to determine the uptake and the metabolism of [3H]T by the mycelium of Penicillium crustosum, cultures of the fungi containing radiolabeled testosterone were developed at different pHs. Also, the metabolism of this androgen in the growth medium of the fungus was determined. Results show that the [3H]T was taken up by the mycelium at pHs 6, 7, 8 and 9. In addition, the presence of [3H]DHT in the incubation medium indicated the participation of 5 alpha-reductase. The maximal activities of this enzyme were determined at pHs 6 and 8, suggesting the presence of two isozymes: type 1 (pH 8), and type 2 (pH 6). Into the mycelium only [3H]T was identified, indicating that isozymes are produced by the fungus under testosterone stimuli.

In order to study lipid synthesis in female hamster flank organs during the estrous cycle, glands were obtained from different animals during different phases of the cycle. Lipid metabolism of [U-14C]glucose was studied under in vitro conditions. The radioactive lipids formed, were extracted from the glands and quantified. An aliquot of the extract was submitted to TLC to isolate and identify the lipids formed. Lipid synthesis in the glands increased significantly during estrous compared with the diestrous phase, suggesting the influence of sex hormones on lipid metabolism in flank organs. The radioactive lipids isolated and identified were: phospholipids, cholesterol, glycerides, waxes, and cholesterol esters. The percentages of conversation from [U-14C]glucose to cholesterol esters were minor in extracts from glands of diestrous animals as compared to estrous and proestrous animals, whereas glycerides and waxes increased significantly in metestrous and diestrous animals. To verify and evaluate the role of estrogen and progesterone in lipid synthesis, three different groups of gonadectomized female hamsters were injected daily with estradiol, progesterone, and 5 alpha-progesterone. After treatments, glands were incubated with [U-14C]glucose to determine the incorporation of radioactive glucose into lipids under culture conditions. The radioactive lipids synthesized were subsequently extracted and identified. The results showed that estrogen had no effect on in vitro [U-14C]glucose incorporation into lipids by flank organs, compared to the vehicle, whereas progesterone and 5 alpha-progesterone increased radioactive lipid synthesis by the glands significantly (p < 0.05). The radioactive lipids isolated and identified from extracts of gonadectomized female hamster flank organs were: phospholipids, cholesterol, triglycerides, waxes, and cholesterol esters. Gonadectomy increased phospholipid synthesis and decreased that of monoglycerides, diglycerides, and waxes. The percentages of conversion from [U-14C]glucose to cholesterol esters were higher after progesterone and 5 alpha-progesterone treatments than in vehicle and estrogen-treatments. Our data indicate that progesterone and 5 alpha-progesterone-treatments increased the in vitro [U-14C]glucose incorporation into lipids in flank organs from gonadectomized female hamsters. Furthermore, the major lipid synthesized by glands under these stimuli were cholesterol fatty acids. Thus, progesterone and 5 alpha-progesterone alter the consistency of sebum from gonadectomized female glands.

We demonstrated for the first time that progesterone and 5 alpha-dihydroprogesterone stimulate [U-14C]glucose incorporation into lipids in gonadectomized female hamster flanking organs. We also found that cholesterol stearate is the major lipid synthesized female hamster flanking organs under progesterone and 5 alpha-dihydroprogesterone stimulation. In this manner, progesterone and 5 alpha-dihydroprogesterone alter the consistency of sebum from gonadectomized female glands.

The 5 alpha-reduction of levonorgestrel (LNG) as well as its binding capacity to the androgen receptors of the hamster flank organ were investigated. Furthermore, the effects of LNG and its 5 alpha-reduced metabolite in the flank organ test and on [U-14C]glucose incorporation into lipids by this tissue were determined. Homogenates from female hamster flank organs were incubated in the presence of [3H]LNG at pH 7.4. The radioactive 5 alpha-LNG metabolite was isolated and its purity was assessed. Competition experiments for androgen binding receptors were carried out with 1.38 nM [3H-7 alpha-17 alpha]dimethyl-19- nortestosterone (DMNT), Kd, plus a range of increasing concentrations of the different unlabeled steroid hormones. The flank organ test was performed in vivo, and [U-14C]glucose incorporation into lipids was determined under organ culture conditions. The 5 alpha-LNG had the same binding capacity to androgen receptors (AR) as LNG in male flank organs. The flank organ test demonstrated that 5 alpha-LNG activity was similar to that observed for levonorgestrel and testosterone (T) on gonadectomized male hamster flank organs. Topical applications of LNG or 5 alpha-LNG increased [U-14C]glucose incorporation into lipids in a way similar to that of T. The overall data indicate that LNG and 5 alpha-LNG produced androgenic activity in the lipid pathway of male flank organs, and that 5 alpha-reduction is not essential for the LNG effect on this tissue.

The role of testosterone and levonorgestrel action on the flank organ by measuring sebaceous gland lipogenesis of female hamsters by the metabolic incorporation of 14C-glucose were investigated. Also, a partial characterization of the radiolabeled lipid fraction was obtained. The effects of in vivo steroids administration were evaluated by 14C-U-glucose metabolic incorporation into lipids by the female hamster flank organs in culture conditions, in the presence or absence of LNG and/or T in the incubation medium. The radioactive lipids were identified by thin layer chromatography. Levonorgestrel alone or together with testosterone on female hamster flank organs decreased the organ weight and sebum content compared with T-treatment alone. In culture conditions, a rapid and significant increase of radiolabeled glucose was observed with T. By contrast when LNG was present in the incubation medium, no differences in 14C-U-glucose incorporation were observed when compared with their controls. When T+LNG were added, a similar result to the obtained when using LNG alone was determined. Testosterone increased glycerides and free fatty acids but decreased polar lipids; whereas LNG did not have any effect in the relative proportions of 14C-U-glucose incorporated into the different classes of lipids, when it was compared with their controls. The results indicated that LNG abolished the increasing effect of 14C glucose incorporation caused by T and changed the lipid composition induced on female hamsters flank organs.

Twenty-two infants with moderate dehydration due to diarrhea in whom oral rehydration therapy (ORT) was contraindicated or who failed to respond to this method of therapy were treated with rapid intravenous rehydration (RIR). Clinical signs of dehydration without shock allowed us to estimate 5% to 10% of weight loss. Patients were 11 days to 19 months old, and 9 of them were undernourished. A standard solution containing 90 mmol/L sodium, 80 mmol/L chloride, 30 mmol/L bicarbonate, 20 mmol/L potassium and 111 mmol/L glucose was used for all patients. The IV infusion was maintained until the rehydration was completed at a rate of 15 to 20 mL/kg/hour. Complete rehydration was successfully achieved in all patients. A total of 89.5 +/- 25.0 mL/kg (mean +/- SD) was needed and the duration of the IV infusion was 5.1 +/- 1.6 hours. Weight gain achieved was 6.5 +/- 1.6%. None of the patients developed hypernatremia following treatment. The initial base deficit, -9.5 +/- 6.6, was reduced to -3.5 +/- 2.9. All of the patients tolerated refeeding immediately after completion of the IV infusion. Our study suggests that this modality of rehydration is well tolerated, safe and effective and enhances the possibility of an early hospital discharge.

Microscopic dissociation constants of 3-hydroxy-alpha-(methylamino)methyl-benzenemethanol have been calculated from the titration spectrophotomeric data (c = 3.8 x 10(-4) M. Ionic strength = 0.16; buffer system: H3BO3/KOH) by application of a spectral deconvolution method. The results found (pKa = 9.48; pKb = 9.71; pKc = 10.12 and pKd = 9.88) are in good concordance with those obtained from the conventional regression linear method (pKa = 9.45; pKb = 9.77; pKc = 10.14 and pKd = 9.81).

The spectrum of doubly ionized tungsten (W III) was produced in a sliding-spark discharge and recorded photographically on the NIST 10.7-m normal-incidence vacuum spectrograph in the 600-2680 Å spectral region. The analysis has led to the establishment of 71 levels of the interacting 5 d 4 , 5 d 3 6 s and 5 d 2 6 s 2 even configurations and 164 levels of the interacting 5 d 3 6 p and 5 d 2 6 s 6 p odd ones. A total of 2636 lines have been classified as transitions between the 235 experimentally determined levels. Comparison between the observed levels and those calculated from matrix diagonalizations with least-squares fitted parameters shows an rms deviation of ±87 cm -1 for the even configurations and ±450 cm -1 for the odd ones.

The in vitro metabolism of 2,2-3-H-androstenedione by the pituitary, hypothalamus, and hippocampus of intact and castrated adult male rats was studied. Conversion of androstenedione to radiochemically pure 5alpha-androstanedione, testosterone, 5alpha-dihydrotestosterone, androsterone, and traces of 3alpha, 5alpha-androstanediol was demonstrated in minced preparations of the three tissues in the absence of cofactors. 5alpha-androstanedione was the metabolite formed in the highest proportion. The pituitary showed the highest enzymatic conversions followed in decreasing order by the hippocampus and the hypothalamus. Castration performed three weeks prior to the experiments resulted in a significant decrease of pituitary 17beta-old-dehydrogenase activity with a concomitant increase of 5alpha-reductase. No significant changes were observed after castration in the hypothalamus and the hippocampus.

Hypothalamic and pituitary gonadotropin function and responsiveness in four patients with well-documented Stein-Leventhal syndrome were studied. All patients were of reproductive age and had had menstrual disorders since menarche. Estrogen production was assessed by measuring the circulating levels of immunoreactive estradiol, by vaginal smears, and by the progestogen-induced menses test. Gonadotropin function was evaluated by measuring the serum levels of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) in blood samples obtained at 15-minute intervals for 150 minutes. Pituitary gonadotropin reserve and responsiveness were studied by giving an intravenous bolus of synthetic LH-releasing hormone (LH-RH) and measuring the circulating gonadotropin levels before and after the injection.