30 



QUATERCENTENARY STUDIES IN PATHOLOGY 



of yeast, there might be a fall in the opsonic index, from "8 to 7, with a 

 subsequent rise to 'g. Marked changes also occurred in the leucocyte 

 count in certain cases. During the first half-hour after a dose of 10 grm. 

 the leucocytes were more than doubled. In the second half-hour there was 

 a fall equal to half the previous rise. In three hours the leucocytes 



sank below the initial level. It has to be 

 noted, also, that some of the patients 

 were taking drugs like benzsosol quinine, 

 terpin hydrate, calcium glycerophosphate, 

 etc., along with the yeast, so that the pure 

 effect of the latter must have been somewhat 

 masked. It seems highly probable, however, 

 from our nuclein experiments presently to 

 be detailed, that the leucocytic and opsonic 

 response (though the latter was undoubtedly 

 very slight) were attributable to the nuclein 

 contained in the yeast. 



Exp. XX. (Chart XX.) Rabbit. Intraperi- 

 toneal injection of 8 cc. of a 5 7o solu- 

 tion of Nuclein.* 



During the first six hours very little 

 variation took place in the leucocyte count 

 apart from a slight neutrophilia. The op- 

 sonic index, however, reached a level of rp 

 at the end of three hours, and of 2*6 at the 

 XX. end of 5 J hours. 



Exp. XXI. (Chart XXI.) Rabbit. Intravenous inoculation (2 cc). 



On this occasion, frequent samples were taken with a view to the 

 demonstration of a negative phase. Very little change took place in the 

 leucocyte count apart from a transient neutrophilia and a slight leucopenia 

 following inoculation. 



*The nuclein used in the experiments was Nuclein Solution No. i, containing 5 % Nucleinic 

 acid (from yeast), manufactured by Parke, Davis & Co. 



(350) 



