SCIENTIFIC PROCEEDINGS 



Abstracts of Communications. 



Seventy-seventh meeting. 



Cornell University Medical College. 

 President Jacques Loeb in the chair. 



I (1179) 



A note concerning strains of Treponema pallidum obtained from 

 the brains of paretics at autopsy. 



By J. A. F. Pfeiffer (by invitation). 



[Government Hospital for the Insane, Washington, D. C] 



For the purpose of obtaining information which might assist 

 in elucidating some of the problems regarding syphilis of the 

 nervous system, and determining whether there is any possible 

 foundation for the assumption that a neurotropic strain of the 

 Treponema pallidum exists, an endeavor has been made in this 

 laboratory to secure strains of the Treponema from the brains 

 at autopsy of cases with parenchymatous syphilis (paresis), by 

 inoculating rabbits with the cortical material; and we have been 

 successful in producing typical lesions in the testicles of rabbits, 

 in which treponemata could be demonstrated. 



It would seem pertinent to review briefly the observations of 

 Noguchi in his work on rabbit syphilis. He distinguishes a 

 difference in the morphology of several strains of Treponema 

 pallidum. Some of the strains appear notably thinner than others, 

 and this variation in morphology seems to have some distinct 

 relationship to the degree of motility, the infectiousness and 

 facility of cultivation. Three different forms are described. A 

 thick form having a width of 0.3 of a micromillimeter, a somewhat 

 thinner one with a thickness of 0.25 of a micromillimeter, and a 

 thin form 0.2 of a micromillimeter in breadth. 



According to Noguchi hard, indurated and sharply defined 



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