ETIOLOGY OF BERIBERI. 407 



where milk is unobtainable, it would appear from their experi- 

 ments that its use was advantageous. 



Recently Tsuzuki ■"' has claimed for a substance, which he 

 calls antihcriberin and which consists of a concentrated alcoholic 

 and ethereal extract of rice-bran, marked therapeutic proper- 

 ties for the cure of human beriberi. However, the strength 

 of the extract employed and the details of the experiments are 

 not given. Nevertheless, our experiment with Group I shows 

 that some substance present in the rice polishings evidently has 

 an effect in preventing the development of beriberi in adult 

 men since 4 of the 6 subjects of the group developed no symp- 

 toms of the disease. It, however, also shows that the substance 

 which seems necessary to prevent the symptoms from appearing 

 is not contained in any large amount in this extract. 



Our opinion in this respect in regard to the alcoholic extract, 

 formed from the results of our experiments, is in accord with 

 that of Cooper and Funk,^' who state that "polishings appear 

 to contain only a very small amount of the active substance," 

 and of Funk *" who believes "the substance is only present in 

 small amounts, probably not more than 0.1 gram per kilogram 

 of rice." Schaumann ^^ claims that only 0.5 gram of the active 

 substance which plays only a mediating part in the metabolism is 

 present in the rice-bran and Simpson ** states that extracts 

 prepared by complicated methods can prolong the life of the 

 animals, but do not restore them fully to health. In his experi- 

 ments birds gained twice as much in weight in three days' treat- 

 ment with yeast as in three weeks' treatment with large doses of 

 the extract which Chamberlain and Vedder employed in their 

 experiments. 



Evidently, symptoms of beriberi may also sometimes occur in 

 individuals (see Case No. 13) in which red rice forms the staple 

 article of diet, when the diet is a very monotonous one compris- 

 ing but few articles and is continued for long periods of time, 

 and the appetite of the subject partaking of it becomes poor 

 and he loses continually in weight.^"^ The influence of work 



"'Beihefte z. Arch. f. Schiffs- u. Trop.-Hyg. (1912), 16. 495. 



''Lancet (1911), 2, 1266. 



"Journ. Physiol (1911), 43. 1400. 



^Arch. f. Schiffs- u, Trop.-Hyg. (1912), 16, 357. 



" Trans. Soc. Trop. Med. & Hyg. (1911), 5, 87. 



" Obviously the food comprising our diets was not subjected to steaming 

 or to prolonged high temperature in cooking as is frequently the case with 

 tinned articles of food. 



