566 



METHODS AND FORMULAS 



MS 32.0-MS 32.1 



proximately one hour. While they are in 

 the oven a beaker full of distilled water 

 should be heated to a temperature of 

 30°C. to 40°C. At the end of the hour, the 

 jar of silver nitrate containing the slides 

 is removed from the oven, and the silver 

 nitrate is either thrown away or poured 

 back into a bottle for further use. The jar 

 is then filled with the warm distilled 

 water and rocked slowly backward and 

 forward for about 30 seconds. This first 

 wash water is thrown away and replaced 

 by a second, which is again used for 30 

 seconds and, in its turn, thrown away and 

 replaced by a third change for a further 

 period of 30 seconds. Immediately after 

 this third wash, the jar is filled with silver 

 protein solution and left at room tempera- 

 ture for about one hour. The silver protein 

 solution is then thrown away — it is im- 

 possible to use this solution more than 

 once — and the jar is rapidly filled with dis- 

 tilled water, which is instantly poured off 

 again. The purpose of this wash is to re- 

 move the silver protein from the glass 

 sUde and jar without removing any ap- 

 preciable quantity from the sections. The 

 jar is then filled with the developing solu- 

 tion and rocked gently backward and for- 

 ward for one or two minutes. The develop- 

 ing solution is then poured away and the 

 jar containing the sUdes left under a 

 running tap for several minutes; running 

 distilled water is better if it is available. 



If tap water is used, the jar and sHdes 

 should be rinsed with a couple of changes 

 of distilled water before pouring in the 

 gold chloride toning solution. This is left 

 until the yellow color of the silver stain 

 has been replaced by the gray color of the 

 gold, when the sHdes may again be rinsed 

 in tap water, and the jar filled with the 

 oxalic acid solution. This stage is rather 

 critical and must be watched carefully. 

 The oxalic acid causes great darkening 

 and, if allowed to act too long, will destroy 

 the sharp differentiation of the stain. The 

 slides should be watched carefully, and the 

 oxalic acid should be poured off and re- 

 placed by running tap water as soon as the 

 first signs of darkening are apparent. This 

 may be anywhere from J^ to % of a 

 minute. Darkening will continue for some 

 time after the slides have l)een in tap 

 water; if one waits until they have become 

 dark before starting the washing, the 

 preparation will be spoiled. After the 

 oxahc acid has been thoroughly washed 

 off, the jar should be filled with sodium 

 thiosulfate for one to two minutes, and 

 then placed in running tap water until all 

 traces of the fixative have been removed. 

 Each slide is then individually removed 

 from the jar and run up through the 

 series of the alcohols and xylene. After 

 each is cleared in xylene it maj' be re- 

 moved and mounted in balsam, which 

 gives a permanent preparation. 



32.1 Neurological Methods 



32.1 Bacsich 1938 test. 1948 Romeis Romeis 1948, 422 



REAGENTS REQUIRED: A. 1% protein silver in a jar, on the bottom of which has been 

 placed 2-3 Gms. of clean metallic copper for each 100 ml.; B. AMS 21.1 Bodian 1936; 

 C. AMS 22.1 Bodian 1936; D. AMS 22.1 Bacsich 1938; E. 5% sodium thiosulfate; 

 F. abs. ale. 50, ether 50 

 method: [celloidin sections of formaldehyde-fixed material, attached to slide with V 21.1 

 Mayer 1884 and varnished with celloidin] -^ A, 1 hr.. 36°C. -^ wash -^ B, till sec- 

 tions are as dark as possible — ^ wash, 1 min. each in 3 changes of water — > C, 5 mins. 

 — > wash — > D, 5 mins. — » wash —> E, 5 mins. — ► wash -^95% ale. till dehydrated -^ 

 F, to remove celloidin -^ balsam, via usual reagents 



32.1 Bodian 1936 763, 65 :89 



reagents required: A. 1% protein silver in a jar, on the bottom of which has been 



placed 2 or 3 Gms. of clean metallic copper per 100 ml.; B. AMS 21.1 Bodian 1936; 



C. AMS 22.1 Bodian 1936; D. 5% sodium thiosulfate 

 method: [paraffin sections of formaldehyde-fixed material]—* water—* A, 12-48 hrs. 



at 37°C. — » wash — * B, 10 mins. — » wash — > C, 5-10 mins. — * wash — > D, 5-10 mins. 



-^ balsam, via usual reagents 



