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The addition of increasing amounts of lysine to a diet of dried bread supplemented with fat, salts, and vitamins brought about significant growth responses in weanling rats. For example, a supplement of 0.5% dl -lysine·HCl, corresponding to 0.2% l -lysine, to a bread diet improved the average gain in weight after 5 weeks from 32% to about 75% of the average gain on the stock diet. An equal response is obtained from lysine added to flour before baking or from lysine added in corresponding amounts to the bread diet. At the end of 6 months the diet containing the supplement of 0.2% lysine had produced rats that were practically equal in weight to those receiving diets with larger additions of lysine. The animals on the basal bread diet did not attain weights comparable with those receiving the lysine supplements. If sufficient lysine was added to bring the total l -lysine content of the diet to about 0.8%, or more, a growth response similar to that obtained with the stock diet was observed. These results suggest that, so far as rat growth is concerned, the only important amino acid deficiency in commercial bread is lysine.

Catalytic quantities of dl -α-lipoic acid have been found to prevent the arsenite inhibition of pyruvate oxidation by S. faecalis 10C1 cells in vitro. This protection is not shared by the higher homolog 3-(6-carboxyhexyl)-1,2-dithiolane, the corresponding disulfhydryl compound (8,10-dimercaptodecanoic acid), nor by the intermediate homolog 7,9-dimercaptononanoic acid. Inhibition of pyruvate oxidation by inorganic mercury, copper, lead, and gold was not prevented by an excess of dl -α-lipoic acid nor of dihydrolipoic acid.

The nutritional effect which may be obtained by the addition of lysine, methionine, valine and threonine to a diet composed of commercial white bread, fat, salts, and vitamins has been investigated with weanling rats. A beneficial effect could be observed only from the addition of lysine. The results of these experiments indicate that, as far as rat growth is concerned, the only amino acid deficiency in commercial white bread is lysine.

SummaryResults with lysine-supplemented experimental diets and with stock diet show that the lipid content of the tibia is relatively low when sufficient lysine for optimum growth is available to young rats. With the lysine-deficient diet, growth is retarded and bone lipids are increased. Interference with production of normal bone marrow appears to be a definite indication of lysine deficiency.

It has been recognized for several years that the terminal stages of nephritis are accompanied by an increase in the inorganic phosphorus of the blood serum and some decrease in the calcium. In 1915 Greenwald1reported observations on the acid-soluble (largely inorganic) and lipoid phosphorus of human blood serum. He observed that normally the acid-soluble phosphorus as P varied between 2 and 6 mg. per hundred cubic centimeters, but that in severe nephritis it might be considerably increased. A year later Marriott and Howland2confirmed these observations and pointed out that the retention of (acid) phosphate would seem to be sufficient to account for the degree of acidosis observed. They found further in most of their cases a marked reduction in the calcium of the serum. They state: What influence this low calcium content may have on the production of such symptoms as convulsions and hemorrhages can only be suggested.

Alkalis play a varying part in the different plans that have been advocated for the medical management of peptic ulcer. They are not used at all in some forms of treatment, while in other forms they are used in small quantities for short periods only. But it has remained for Sippy to work out a thorough, detailed method of using alkalis with ulcer-bearing patients, which is one of the most important parts of his form of treatment. He insists on the necessity of destroying the corrosive, disintegrating and digestive effect of the gastric juice, pointing out that it is best done by continuously neutralizing the free hydrochloric acid with alkalis; for the digestive properties of pepsin are lost in the absence of free acid. It is true that it is not yet known just what part the acidity of the gastric juice plays in the formation or the delayed healing