794 Syphilis 



ment of sterile rabbit's testis was added, after which the tubes 

 were incubated at 37 C. for two days to determine their 

 sterility. To each tube the material from the inoculated 

 rabbit's testis, rich in the treponema, is added, after which the 

 surface of the medium in each receives a thick layer of sterile 

 paraffin oil. As the most strict anaerobiosis is necessary, the 

 tubes are placed in a Novy jar, the bottom of which contains 

 pyrogallic acid. Noguchi first passes H gas through the 

 jar, permitting it to bubble through the pyrogallic acid solu- 

 tion for ten minutes. He then uses a vacuum pump to ex- 

 haust the atmosphere in the jar, and lastly permits the alka- 

 line solution (KOH) to flow down one of the tubes to mix with 

 the pyrogallic acid. 



In these cultures the pallidum grows together with such 

 bacteria as may have been simultaneously introduced. To 

 secure the cultures free from these bacteria Noguchi permitted 

 the treponema to grow through a Berkefeld filter, which for 

 a long time held back the other organisms. Later it was found 

 that both bacteria and treponema grow side by side in a deep 

 stab in a serum-agar-tissue medium. Under these conditions 

 the bacteria grow only in the stab or puncture, but the trepo- 

 nema grow out into the medium as a hazy cloud. By cau- 

 tiously breaking the tube and securing material for transplan- 

 tation from such a scarcely visible cloud, the organisms may 

 be transplanted from the new media and pure cultures thus 

 obtained. 



In a later paper, Noguchi* details the cultivation of the 

 treponema from fragments of human chancres, mucous 

 patches, and other cutaneous lesions. The medium employed 

 is a mixture of 2 per cent, slightly alkaline agar and i part of 

 ascitic or hydrocele fluid, at the bottom of which a fragment 

 of rabbit kidney or testis is placed. The medium is prepared 

 in the tubes, after the addition of the tissue, by mixing 2 

 parts of the melted agar at 50 C. with i part of the ascitic 

 or hydrocele fluid. After solidification a layer of paraffin oil 

 3 cm. deep is added. 



A considerable number of tubes should be prepared at the 

 same time and incubated for a few days prior to use to deter- 

 mine sterility. The bits of human tissue are snipped up with 

 sterile scissors in salt solution containing i per cent, of sodium 

 citrate and should be kept immersed in this fluid from the time 

 of securing to the time of planting, so as not to become dried. 

 * "Journal of Experimental Medicine," 1912, xv, i, p. 90. 



