F. C. Koch

Procedure for Quantitative Extraction of Sex Hormones from Urine

Summary and Conclusions 1. A method for the extraction and assay of male and female hormones from normal urines has been described. 2. This procedure consists in 2-hour acid hydrolysis of the urine, extraction with ten times the volume of benzene using the extractor described, and separation into male and female fractions by alkali. 3. The assay is conducted with standards in parallel and results expressed in international units. 4. An alternative procedure for male hormone alone using an adsorption process is likewise described.

Effect of Testosterone Propionate in Eunuchoidism

Conclusion Testosterone propionate causes enlargement of the prostate and progression of secondary sex characters in the eunuchoid, together with a gain in weight, nitrogen and sodium retention, and a slight increase in the basal metabolic rate.

Amorphous Pepsin of Higher Activity Than Crystalline Pepsin from Commercial and Crystalline Pepsin

Summary 1. Coagulated egg white removes peptic activity from concentrated solutions of commercial and crystalline pepsins. 2. The pepsins recovered by elution from the egg white are more active than crystalline pepsin. Preparations No. 1 and No. 2 from commercial pepsin and preparation P-3B from crystalline pepsin are respectively 1.5 to 1.7 and 2.5 to 3.0 times as active as crystalline pepsin. 3. Preparations No. 1 and No. 2 have about the same activity as the product Herriott et al. isolated from crystalline pepsin by salt fractionation while preparation P-3B has the same activity as the fraction isolated by the same workers by salt fractionation from (a) pepsinogen, and (b) crystalline pepsin prepared from pepsinogen.

Studies on Hemoglobin Formation in the Rat.

Conclusions 1. Wheat gluten is an adequate dietary protein for promoting hemoglobin synthesis in the rat. Casein is not superior to wheat gluten for this purpose. 2. Hemoglobin and tryptophane in the diet are no better utilized than gluten for hemoglobin production in the rat. 3. The blood forming process in the rat is not & pendent upon the presence of vitamins A, B, or E in the diet.

A New Apparatus and an Improved Method for Chromato-graphic Adsorption

Summary A new apparatus whose advantages are increased speed and uniformity of column has been described. A new method of working with colorless, non-fluorescent compounds by use of a color reaction has also been reported.

Nutritional Value of Proteins as Influenced by Exposure to Ultraviolet Irradiation.

The experiments described below include (A) in vitro digestion experiments on irradiated and non-irradiated proteins with pepsin and trypsin respectively and (B) growth and metabolism studies on rats kept on low protein diets where the protein was either irradiated or non-irradiated. A. In vitro Digestion Experiments on Irradiated and Non-irradiated Purified Proteins with Pepsin and Trypsin, Respectively. 1. Tryptic Digestion of Casein. The irradiated product was prepared by exposing dry casein (Merck according to Hammarsten) for 2 1/2 hours at a distance of 18 inches to the mercury quartz lamp in a current of air. The digestion experiments with irradiated and non-irradiated casein were carried out as described by Helmer. 1 At the end of the digestion period the undigested protein was precipitated and the refractive indices of the filtrates read. As shown in Table I, the non-irradiated casein is somewhat better digested than the irradiated. The refractive index readings were confirmed by actual determination of nitrogen in the filtrates. 2. Peptic Digestion of Egg-White. Dried egg-albumin was prepared and digestion experiments carried out according to the method described by McMeekin and Freeland. 2 A portion of the dried, powdered material was irradiated for 4 hours in a current of air; the longer irradiation period being used because of the coarse physical state of the protein. Here again the amount of digestion was slightly greater for the non-irradiated protein than for the irradiated (Table II). B. Growth and Metabolism Studies on Rats Kept on Diets Low in Irradiated and Non-irradiated Proteins. 1. Group Experiments. In spite of the very slight differences in digestibility between the irradiated and non-irradiated proteins, the final test of actual feeding experiments was obviously the next step.