Double isotope dilution derivative technique for testosterone glucuronoside in urine

A double isotope dilution derivative technique for the determination of testosterone glucuronoside in urine has been developed. This is a highly specific and sensitive method which is applicable to the measurement of testosterone in submicrogram amounts in urine and other biological fluids. This method has been used to study normal prepubertal and pubertal males, normal females and subjects with gonadal dysgenesis, Cushing's syndrome, congenital adrenal hyperplasia, idiopathic hirsutism, Addison's disease and hypogonadism. The patients were studied after stimulation and suppression of gonads or adrenal glands to delineate the source of the androgen and its physiological control mechanism. The testosterone production of normal males determined by the method presented herein corresponds to results of others.

Aflatoxin production and degradation by Aspergillus flavus in 20-liter fermentors

Yields of from 200 to 300 mg per liter of aflatoxins B(1) and G(1) were produced by two strains of Aspergillus flavus in 20-liter fermentors under proper conditions of inoculum (well-dispersed growth) and aeration (0.5 volume per volume per min of air, 300 rev/min, 30 psi back pressure, baffles). Peak yields were usually attained in 72 hr, after which the aflatoxin concentration declined rapidly. Degradation of aflatoxin depended primarily on mycelial lysis and high-aeration conditions. Cultures previously reported not to degrade aflatoxin could be induced to do so under these conditions. The percentage and rate of toxin degradation were independent of toxin concentration, and appeared to be nonenzymatic and nonspecific. Degradation simulating that occurring in the fermentor was achieved by reacting aflatoxin with peroxidized methyl esters of vegetable oil; initial degradation was rapid and appeared to involve a complex series of reactions.

Aldosterone excretion in normal children and in children with adrenal hyperplasia

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Solubility of krypton and xenon in blood, protein solutions, and tissue homogenates

The solubility of krypton and xenon in human serum albumin solutions, in hemoglobin solutions, in human blood, rabbit muscle, and beef brain homogenates has been measured at 1 atm total pressure and at temperatures of 25, 30, and 37 C. The solubilities of krypton in 1 g human albumin were found to be 0.0624, 0.0412, and 0.0195 ml at 25, 30, and 37 C, respectively. The amount of xenon dissolved in 1 g human albumin was found to be 0.2382, 0.1954, and 0.1493 ml at 25, 30, and 37 C, respectively. The amount of krypton and xenon dissolved in 1 g hemoglobin at 37 C was 0.0247 and 0.3661 ml, respectively. The solubility of cyclopropane in human serum albumin and hemoglobin solutions was calculated from the literature. The solubility coefficient of krypton, xenon, and cyclopropane in these biological solutions was found to be the sum of the solubility coefficients of the respective gas in the individual components of the biological solution. The solubilities of krypton and xenon in biological solutions decrease as temperature is raised.

krypton, xenon, and cyclopropane; measurements of gas solubility; human blood—krypton and xenon solubility; human albumin—krypton, xenon, and cyclopropane solubility; human hemoglobin—krypton, xenon, and cyclopropane solubility; rabbit's muscle homogenate—krypton and xenon solubility; beef's brain homogenate—krypton and xenon solubility

Submitted on September 28, 1964