362 



SUMMARY OF CUERENT RESEARCHES RELATING TO 



Synthetic Culture-Medium for Tubercle Bacilli.* — P. Arrnand- 

 Delille, A. Mayer, G. Schaeffer and E. Terroine have made an analytical 

 study of glycerin-peptone broth, and have applied the information derived 

 from this to the prescribing of a synthetic medium of precise chemical 

 composition, suitable for the cultivation of B. tuberculosis. They found 

 that, whereas purin bases had no influence upon the growth of the 

 organism, certain extractives (particularly creatin, carnosin and sarcosin) 

 favoured growth, and sugars, such as inosit and glucose, were essential. 

 Study of protamines led them to include diamido acids such as arginiu 

 and histidin, and these had a markedly favourable influence upon 

 growth. Several satisfactory broths were obtained, and one of the 

 following composition gave perhaps the best results : — 



Sodium chloride .. .. 1 



Magnesium citrate .. . 



Monopotassium phosphate 1 



GlycocoU 



Aspartic acid 



Carnosin nitrate . . . . 



Creatin 



hydrate (Centi- 



Cultivation of Mycobacterium Enteritidis.f — F. W. Twort and 

 Gr. L. Y. Ingram have succeeded in growing this acid-fast bacillus, the 

 causal organism of Johne's pseudo-tuberculous enteritis of cattle, upon 

 media which contain the dried and powdered growth of certain killed 

 acid-fast bacilli. The most suital)le bacillus for incorporating in the 

 medium is the timothy-grass baciHus ; the smegma bacillus, the 

 nasenschlein bacillus of Karlinski and the human tubercle bacillus may 

 also be used. Negative results were obtained with bovine and avian 

 tubercle. The essential substances may be extracted from suitable 

 bacilli by means of hot ethyl alcohol. Successful results were obtained 

 even in cases where the dead bacteria had been kept for eight years and 

 autoclaved for one hour at 115° C. 



(2) Preparing- Objects. 



Preparation of Medullary Sheath Sections. | — Rappricht has 

 employed Spielmeyer's method — a modification of Heidenhain's iron- 

 hsematoxylin process — with success, but found difficulties in making 

 the frozen sections adhere to the slide. By the use of tissue-paper, 

 treated with a mixture of collodion (3 parts) and castor-oil (1 part) 

 dissolved in alcohol-ether, he obtained satisfactory results. The sections 

 were transferred from the mordant solution to 70 p.c. alcohol, and from 

 this to the prepared paper strip. If smoothed carefully on to the paper, 

 the sections will adhere to it during subsequent staining and dehydrating 

 processes. From carbolxylol the paper and sections — sections down- 

 wards — are placed upon slides, and the paper is freed by treating with 

 acetone according to Strasser's method. The sections will remain fixed 

 to the slide for the clearing and mounting processes. 



* Comptes Rendus, cliv. (1912) pp. 537-9. 



t Proc. Roy. Soc, Series B, Ixxxiv. (1912) pp. 517-42. 



X Zeitschr. wiss. Mikrosk.. xxviii. (1912) pp. 278-85. 



