142 



Scientific Proceedings (92). 



extracted with absolute or 95 per cent, alcohol, possessed anti- 

 scorbutic qualities, whereas the residue was of no value in this 

 respect. Neutralized orange juice, given subcutaneously to a 

 group of guinea pigs, also failed in this respect. "Artificial orange 

 juice," made up according to McCollum's formula, composed of 

 the various salts, citric acid, and sucrose in the proportions which 

 they are found in the natural juice, was given to numerous pigs, 

 but was ineffective in protecting them against scurvy. 



"Artificial orange juice" was likewise tried in the treatment of 

 two infants suffering from scurvy. In both it failed absolutely 

 to ameliorate the symptoms, which yielded rapidly to natural 

 orange juice. 



We wish to report especially that orange juice may be given 

 intravenously, after it has been boiled, and made slightly alkaline 

 to litmus, by the addition of normal sodium hydrate just before 

 using, and that such injections produce no untoward reaction, 

 and have a marked curative effect. This intravenous therapy is 

 of interest from a practical standpoint, as its action has been found 

 to be most rapid, and its dosage small; it is therefore especially 

 indicated where the symptoms are urgent. It is also of theoretical 

 interest in a consideration of the pathogenesis of scurvy, as it is 

 the first time that this disorder has been cured by a therapy which 

 was not introduced by way of the alimentary tract. 



194 (1372) 



A delicate method of determining invert activity. 



By C. K. Watanabe and V. C. Myers. 



[From the Laboratory of Pathological Chemistry, New York Post- 

 Graduate Medical School and Hospital.] 



A delicate method of estimating invert activity (sucrase) 

 would be of advantage in connection with a number of physiologi- 

 cal problems. A substitution of one per cent, cane sugar for the 

 one per cent, soluble starch or glycogen, employed by Myers and 

 Killian, 1 in the estimation of the diastatic activity of the blood, 

 furnishes a very delicate method for sucrase. 



1 Myers and Killian, Jour. Biol. Chem., 1917. XXIX, 179. 



