Effects of ethanol on rat hypothalamic luteinizing hormone releasing hormone. A study utilizing radioimmunoassay

To further understand the mechanism of action by which ethanol (ETOH) decreases plasma luteinizing hormone (LH) levels, the effects of multiple i.p. injections of EOH (1.0--1.5 g/kg) or saline on hypothalamic luteinizing hormone releasing hormone (LHRH) and plasma LH concentrations were evaluated in intact and castrate male rats. After injections, animals were decapitated, brains rapidly removed, and blocks containing the hypothalamus [with median eminence (ME)] were isolated. Hypothalami were subjected to acetic acid extraction and LHRH content quantitated via radioimmunoassay (RIA). Hypothalamic LHRH was found to be inversely correlated with plasma LH. In response to castration, both saline and ETOH-treated rats showed a decrease in hypothalamic LHRH content with a concomitant increase in plasma LH; however, the ETOH-treated animals retained significantly greater concentrations of LHRH and showed significantly lower plasma LH levels when compared to saline-treated controls. Likewise, ETOH-treated intact animals showed significant increases in LHRH content, with LH levels remaining significantly lower than the saline-treated intact controls. Thus, these data from both intact and castrate rats provide evidence to support the hypothesis that alcohol-induced decreases in LH levels are due to a diminished release rate of hypothalamic LHRH.     

Quantitative Nasal Culture: a Tool in Antibiotic Research

The use of the quantitative nasal culture was investigated as a means of evaluation of new antimicrobial drugs in man. Cyclacillin was somewhat more active in vitro than penicillin G against penicillin G-resistant organisms. Cyclacillin was highly effective in suppressing staphylococci susceptible to penicillin G in nasal carriers but did not suppress staphylococci resistant to penicillin G. Although in previous studies by others cyclacillin was effective in treating mice infected with penicillin G-resistant staphylococci, in the present studies cyclacillin was not effective in suppressing nasal penicillin G-resistant staphylococci in man at doses which markedly suppressed penicillin G-sensitive organisms.     

The isolation of cholest-5-ene-3β,26-diol from human brain (Short Communication)

Cholest-5-ene-3beta,26-diol, isolated from human brain, was further characterized by oxidation to 3-oxocholest-4-en-26-ol and to 3-oxocholest-4-en-26-oic acid. Identification was achieved by comparison (by t.l.c., g.l.c. and g.l.c.-mass spectrometry) with corresponding reference compounds derived from kryptogenin.     

Filtering rate of the cladoceran,Daphnia pulex as a function of body size,light and acclimation

Daphnia pulex were raised under nine light intensities (0, 1.7, 3.5, 7, 14, 28, 55, and 110 ft-c), polarized light (6.6 ft-c), and four wavelength ranges.Light intensity significantly affected the relationship between filtering rate and body size of unacclimated animals. The b values were lowest at 7 and 14 ft-c and they increased above 7 ft-c as light intensity increased. There were significant differences among b values and adjusted means for unacclimated animals. Acclimation to their respective conditions resulted in some significant differences between b values and adjusted means. For acclimated animals there were no significant differences among b values but there were some differences among adjusted means. The filtering rates of unacclimated and acclimated animals were lower at 14 ft-c while 1.7 and 3.5 ft-c were generally stimulatory and the effect was more pronounced in larger animals. Light intensities above 28 ft-c tended to suppress the filtering rate of small unacclimated animals and stimulate filtering rate in larger unacclimated animals. After acclimation, intensities above 7 ft-c did not affect the filtering rate of either small or large animals.The effect of polarized light on filtering rate was inseparable from the effect of light intensity, however, acclimation to polarized light resulted in a significantly higher b value.There were no significant effects of wavelength among b values for unacclimated animals and the adjusted mean for blue wavelengths was significantly higher than for violet wavelengths. There were no significant differences among b values or adjusted means for acclimated animals. Acclimation to their respective wavelengths did result in some significant differences between b values and adjusted means. Except for the effects of blue wavelengths on unacclimated animals and red wavelengths on acclimated animals, the effects of wavelengths are inseparable from the effects of light intensity.This paper is part of a Ph.D. Thesis submitted to the Faculty of Graduate School of The University of Kansas.Supported in part by a NSF Summer Traineeship and a grant from the Research Corporation to St. Olaf College, Northfield, Minnesota 55057.     

Biochemical Studies of Bacterial Sporulation and Germination XIII. Adenylate Kinase of Vegetative Cells and Spores of Bacillus subtilis

The spore and vegetative cell adenylate kinases of Bacillus subtilis, purified about 1,000-fold, proved indistinguishable by several physical and functional tests, including polyacrylamide gel electrophoresis, DEAE cellulose chromatography, and specificity toward substrates. Adenylate kinase activity in cell extracts, followed throughout growth and sporulation, was found to reach a maximum near the end of exponential growth, remain at that level during sporulation, until shortly before the appearance of refractile forms, and then decline, along with total protein, during the subsequent maturation of the spores. The enzyme, stable in extracts of exponential growing cells, was unstable in extracts of sporulating cells, presumably as a result of degradation by protease(s) appearing after the end of exponential growth.     

Biochemical Studies of Bacterial Sporulation and Germination XIV. Phospholipids in Bacillus megaterium

The principal phospholipids of Bacillus megaterium throughout the cycle of growth and sporulation were found to be phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, and a hitherto unidentified isomer of glycosaminyl-phosphatidylglycerol. Phosphatidylglycerol predominated during vegetative cell growth and then declined as spores developed, whereas diphosphatidylglycerol became more prominent during spore maturation. The latter phosphatide was relatively inaccessible in the vegetative cell and was more accessible in the spore, as judged by solvent extraction under various conditions.     

Histoplasmosis in Montreal During the Fall of 1963, with Observations on Erythema Multiforme

Although Montreal is in an endemic area, significant clinical histoplasmosis with systemic manifestations has been, until recently, infrequently diagnosed. However, since the autumn of 1963, 31 cases of clinically significant histoplasmosis have been seen by the authors. These were divided into two groups: (1) patients in whom the diagnosis was established on the basis of histological and/or cultural demonstration of the fungus; (2) patients in whom the diagnosis was based on a positive histoplasmin skin test, a complement fixation antibody titre of 1:32 or greater and compatible clinical and radiological findings. An additional group of 11 patients who presented with erythema multiforme was investigated and a heretofore unrecognized relationship between histoplasmosis and erythema multiforme was established.