1916] FOODS — HUMAN NUTRITION. 863 



This view is supported by the results of other investigators cited from the 

 literature. 



The influence of ingested carbohydrate, protein, and fat on the blood sugar 

 in phlorizin diabetes, F. A. Csonka {Jour. Biol. Chem., 20 (1916), No. 1, pp. 

 93-9S, fig. i).— Following the ingestion of 20 gm. of glucose by phlorizinized 

 laboratory animals (dogs) the blood sugar readied the maximum at the second 

 hour and declined to the original level at the fourth hour. It was found In 

 earlier experiments (E. S. R., 33, p. 755) that 94 per cent of 16 gm. of glucose 

 given to a phlorizinized dog was excreted during the first five hours as " extra 

 glucose." 



As the elimination of the ingested glucose was practically complete and the 

 curve of blood sugar was parallel to that of extra glucose, the conclusion is 

 drawn that no glucose was deposited between the periods of absorption and 

 elimination. 



" That the blood sugar is increased after ingestion of protein is apparent 

 from the curve which shows that the endogenous glucose derived from meat 

 protein and gelatin appears in the blood as glucose — at least, partially so — since 

 the isoglucogenic quantities of ingested endogenous and exogenous glucose 

 should give the same increase of blood sugar. The ingestion of fat, which does 

 not produce ' extra glucose,' did not cause any appreciable increase in blood 

 sugar." 



Studies of urinary and blood nitrogen curves after feeding in the dog, 

 O. H. P. Pepper and J. H. Austin (Proc. Soc. Expt. Biol, and Med., 12 (1915), 

 No. 8, pp. 179-181). — The daily variation in the nonprotein blood nitrogen in a 

 normal dog receiving a diet containing 0.4 gm. of nitrogen per kilogram of body 

 weight was about 9 mg. The maximum was reached about 2 hours after feed- 

 ing, and the original level was reached in about 10 to 14 hours. The feeding 

 of excessive quantities of meat increased the nonprotein blood nitrogen from 25 

 to 40 mg. in from 6 to 8 hours and the original level was not reached at the 

 end of 24 hours. The curve of nonprotein blood nitrogen in a normal dog after 

 feeding followed closely the curve of the urinary nitrogen. 



" In the fasting dog there occurs a gradual fall in blood nitrogen to a minimum 

 of from 12 to 18 mg., reached in from 30 to 48 hours after the last feeding, and 

 followed by a rise in the next few hours to about 25 mg., at about which level 

 it tends to persist. The urinary nitrogen shows a similar but less pronounced 

 curve." 



The elimination of ammonia in the urine during rest, D. Liotta (Arch. 

 Farmacol. Sper. e Sci. Aff., 22 (1916), No. 6, pp. 205-228, figs 5).— ExT)eriments 

 are reported with laboratory animals (dogs) and human beings, which show 

 that the elimination of ammonia in the urine increased notably during rest. 



The metabolism of sulphur. — I, The relative eliminations of sulphur and 

 nitrogen in the dog in inanition and subsequent feeding, H. B. Lewis (Jour. 

 Biol. Chem., 26 {1916), No. 1, pp. 61-68).— The author reviews critically the 

 w^ork of other investigators on the excretion of sulphur as related to nitrogen 

 elimination and reports the results of his own experiments on this subject. In 

 the case of laboratory animals (dogs), determinations were made of the nitro- 

 gen and sulphur elimination during periods of prolonged fasting and during 

 subsequent shorter periods of alternate fasting and feeding. 



The experimental data showed no evidence of any increasing retention of 

 sulphur as compared with nitrogen. The nitrogen : sulphur ratio during the 

 fasting periods, with two exceptions, varied within narrow limits (from 14 to 

 15 for the most part). 



The author states that if a partial conservation of the protein molecule in 

 ceUular catabolism can be effected by the organism, as has been sugge.sted by 



