366 SUMMARY OF CUKKENT RESEARCHES RELATING TO 



Staining- Negri's Corpuscles.* — M. Stutzer stains paraffin sections 

 with dilute Loeffler's solution for 5 to 10 minutes ; differentiates with 

 10 p.e. tannin solution for from 1 to 5 minutes, according to the thickness 

 of section. The differentiation is watched under the Microscope, and 

 as soon as the outlines of the nuclei are plainly visible the preparation 

 is washed with water, mopped up with blotting-paper, passed rapidly 

 through absolute alcohol to xylol and balsam. The Negri bodies are 

 reddish violet, the nerve-cells blue. 



Demonstrating Connective-tissue Fibres.f — Snessarew adopts the 

 following procedure : — A piece of fresh tissue fixed in formalin is placed 

 for some days in a 2h p-c. solution of iron alum {(NH^)^ Fe., (80)4}. 

 After a wash it is treated with 2 p.c. formalin for 2 hours. It is then 

 washed in running water for 30 minutes or longer, and then frozen sec- 

 tions are made. The sections are placed for 24 to 48 hours in 10 p.c. 

 silver nitrate solution. Each section is quickly washed in distilled water, 

 and this is followed by silver-ammonium solution for 5 minutes. After a 

 rapid wash in distilled water it is placed in 10 to 20 p.c. formalin. After 

 this follows presumably the ordinary technique — this is only indicated by 

 the formula, etc. 



The silver-ammonium solution is prepared by mixing 5 parts of 10 p.c. 

 silver nitrate and a similar number of drops of 40 p.c. caustic soda : after 

 a good shake 20 to 25 parts of distilled water are added. The solution 

 is again thoroughly shaken and the precipitate allowed to settle. The 

 supernatant liquid is decanted off, and this forms solution A. To it 

 are added drops of ammonia until it becomes clear. Solution B is 

 prepared from the precipitate l)y adding ammonia until it is all dis- 

 solved and the solution is quite clear ; it is then diluted to 20-25 

 parts (sic). Solution A is not active ; in it the solutions become only 

 blackish-brown : the proper reaction is obtained by means of the fluid B. 

 How much of B should be used can be ascertained only by trying the 

 effect. 



Methods of Staining- Tubercle Bacilli. $— J. Bohm has studied the 

 various methods that have been recommended for the purpose of stain- 

 ing tubercle bacilli, particularly for the purpose of assessing their relative 

 values in the routine examination of sputa. Of the modern processes 

 those discussed most fully are the methods of Ziehl-Neelsen, Herman, 

 Much and Gasis. The last-named method, that of Gasis, possesses a 

 scientific interest, illustrating the alkali-fast property of tubercle bacilli. 

 The technical difficulty of the method, however, and lack of constancy 

 in the reaction render it unsuitable for routine purposes. Much's 

 modification of Gram's method has yielded important results in the 

 study of tuberculous lesions, where organisms, not otherwise found, have 

 been demonstrated by its means. For the present purpose, however, 

 the results obtained by this method may lack the precision required for 

 rapid diagnosis. The Ziehl-Neelsen method has stood the test of time, 



* Zeitschr. Hygiene u. Infektions, Ixix. (1911) p. 25. 



t Anat. Anzeig., xl. (1912) pp. 522-40 (12 figs.). 



X Centralbl. Bakt., He Abt., Orig., Ixii. (1912) pp. 497-520. 



