POODS — HUMAN NUTRITION. 261 



nated than under normal conditions. The percentage of creatinin nitrogen 

 decreased with the increase of total nitrogen ; consequently, the elimination of 

 this substance is not proportional to the total nitrogen. If, however, creatln 

 nitrogen be considered as creatinin nitrogen, the total of such nitrogen Is 

 nearly that of the normal percentage of creatinin nitrogen. 



When the nitrogen of the normal mixed diet is replaced with fat, the or- 

 ganism tends to retain nitrogen which is eliminated in smaller proportions 

 than in mixed feeding or in total fasting. The quantity of creatinin eliminated 

 is also smaller, but the appearance of small quantities of creatin is not pre- 

 vented. The daily percentages of creatin nitrogen and creatinin nitrogen vary 

 less than in complete fasting. There appears to be a relation between endog- 

 enous nitrogen and creatin and creatinin. Therefore, the quantity of creatin 

 eliminated is not proportional to the amount of nitrogen ingested. 



Purin metabolism with diminution of the processes of oxidation in the 

 organism, V. Scaffidi (Arch. Ital. Biol., 59 {1913), No. 2, pp. 172-179).— The 

 experiments here noted were made with 2 types of laboratory animals, those 

 (dogs) in which the uric acid eliminated is the result of oxidation and those 

 (ducks) in which it is of synthetic origin. In both groups, the animals were 

 previously kept on a purin-free diet and then made to inhale air containing 

 different amounts of carbon dioxid and oxygen. 



When the conditions determining a temporary variation in the processes of 

 oxidation had thus been controlled, it was found that they had no influence 

 on the uric acid metabolism of the dogs. In the experiments with ducks, how- 

 ever, temporarily limiting the oxidation of the tissues caused an increased for- 

 mation of uric acid. This fact is to be explained by assuming either that the 

 slight uricolytic power of the ducks is lessened by the conditions of the experi- 

 ment or that the synthesis of uric acid is facilitated by the products of the 

 breaking down of the protein molecule. 



Purin metabolism during- fasting, V. Scaffidi (Arch. Ital. Biol., 59 {1913), 

 No. 2, pp. 180-192). — Ducks and dogs were used in these experiments as types 

 of animals in which the uric acid eliminated was formed by synthesis and oxi- 

 dation, respectively. 



In the case of ducks, the author concludes that the uric acid eliminated 

 represents from 42 to 53 per cent of the total nitrogen metabolism. During 

 fasting and overfeeding it follows closely the variations of total nitrogen. The 

 proportion of total to uric nitrogen rose dui'ing high feeding and fell during 

 complete fasting. 



In the case of dogs, fasting produced only slight modifications in the purin 

 metabolism, the quantity eliminated diminishing without any apparent rela- 

 tion to the total nitrogen. 



The problem of intermediary purin metabolism. — I, The storage of purin 

 in the liver and its relation to the excretion of uric acid, H. Rosenbeim} 

 {Ztschr. Expt. Path. u. Thei\, 14 {1913), No. 2, pp. 245-254, fig. i).— This article 

 describes experiments made with the surviving livers of dogs and planned to 

 show the effect of atophan on the storage and metabolism of purin bodies in 

 the liver. Its effects in cases of gout, etc., under difCereut dietary conditions 

 are also touched upon. 



The problem of intermediary purin metabolism. — II, Concerning uric acid 

 puncture, E. Michaelis {Ztschr. Expt. Path. u. Ther., 14 {1913), No. 2, pp. 

 255-261, fig. 1). — These experiments were made with rabbits on which the oper- 

 ation known as the Claude Bernard sugar puncture had been performed. The 

 operation increased the allantoin and also the total nitrogen content of the 

 urine notably. 



