768 Syphilis 



cautiously broken at some appropriate part and the transplanta- 

 tion made from the opalescent part of the medium to fresh approj- 

 priate culture-media. By these means, after a few trials, pure 

 cultures of Treponema were secured. 



The colonies were never sharp, but always faintly visible. There 

 is no color and no odor. 



By inoculating the organisms recently secured from human 

 lesions (by the method given) into monkeys (Macacus rhesus and 

 Cereopithicus caUitrichus) Noguchi was able to produce typical 

 syphilis of the monkey, thus showing that the virulence of the 

 organisms was not lost in the cultivation. 



Zinsser, Hopkins and Gilvert* found it possible to grow Tre- 

 ponema paUidum in massive cultures in fluid media. They em- 

 ployed a flask with a long slender neck like a "specific gravity flask." 

 The flask was fiUed with slightly acid (0.2 to 0.8 per cent, acidity) 

 broth containing sheep-serum, ascitic fluid, horse-serum or rabbit- 

 serum, with an addition of autoclaved and hence thoroughly steril- 

 ized tissue (kidney, liver, brain, lung or heart muscle) and covered 

 with sterile neutral paraffine oil. The cultiure contains the greatest 

 number of organisms after three weeks. To collect them for mak- 

 ing Itietin, etc., the fluid in the flasks was poured into tubes and 

 centrifugated for a short time to throw down scraps of the nutrient 

 tissue, the fluid then decanted and recentrif ugated rapidly and for 

 a longer time to throw down the micro-organisms. 



Pathogenesis and Specificity.— There can be no doubt about the 

 causal relation of Treponema pallidum to syphilis. It is unknown 

 in every other relation; it has appeared in every required relation, 

 and thus has completely fulfilled the laws of specificity laid down by 

 Koch. Treponema pallidum is- not only pathogenic for man, but, 

 as has aheady been shown, can also be successfully implanted into 

 chimpanzees, macaques, rabbits, guinea-pigs, and other experi- 

 ment animals. As syphilis is, however, unknown under natural 

 conditions, except in man, it may be looked upon as a human disease. 



The organism enters the body through a local breach of con- 

 tinuity of the superficial tissues, except in experimental and con- 

 genital infections, where it may immediately reach the blood.- 



In ordinary acquired syphilis the point of entrance shows the 

 first manifestations of the disease after a period of primary incuba- 

 tion about three weeks long, in what is known as the primary lesion 

 or chancre. This appears as a papule, grows larger, undergoes super- 

 ficial indolent ulceration, and eventually heals with the formation 

 of an indurated cicatrix. It is in the chancre that the treponema 

 first makes its appearance. From this lesion, where it multiphes 

 slowly, it enters the lymphatics and soon reaches the lymph-nodes', 

 which swell one by one as its invasion progresses. During this 

 stage of glandular enlargement the organisms can be found in small 

 * "Journal of Experimental Medicine," 1915, xxi. No. 3, p. 213. 



