DS 13.40-DS 13.41 



DYE STAINS OF GENERAL APPLICATION 



359 



is designed to remove not only the whole 

 of the adherent stain from the slide, but 

 to permit the oxalic acid also to leach out 

 of the tissues. No differentiation of the 

 stain should take place in water, because 

 such differentiation as is necessary is pro- 

 duced bj' the absolute alcohol used in the 

 next stage for dehydration. It is difficult 

 to take sections stained by this method 

 up through the usual graded series of 

 alcohols, nor will any grave damage be 

 occasioned by the omission of this step. 

 If, however, the preparator is one who 

 insists that his sections should pass through 

 a graded series, mixtures of acetone and 

 water should be substituted for alcohol 

 and water. When the sections reach abso- 

 lute alcohol, they should be watched very 

 closely while being moved continuously 

 up and down in the alcohol. The blue will 

 leave them in great clouds and these 

 clouds will taper off quite rapidly, leaving 

 a terminal point at which no color leaves 

 for a moment or two before a slow stream 

 again starts to appear in the alcohol. As 

 soon as the initial color clouds are seen to 

 cease, the sections should be placed in 

 xylene which stops the differentiation. 



If the preparator is uncertain of this 

 method, or is trj'ing it for the first time, 

 it is recommended that the slides be 

 thoroughly washed in absolute alcohol Ijut 



removed to xjdene before the color clouds 

 have ceased to leave. Examination under 

 the low power of the microscope will now 

 show these prejiarations to have a dull 

 purple muscle and an intensely blue con- 

 nective tissue. A few trial sections sliould 

 now be returned to absolute alcohol for a 

 few moments and then back into xjdene 

 and reexamined. It is possible by this 

 means to exercise perfect control over the 

 differentiation, which should be stopi)ed 

 when the muscles and nuclei are clear red, 

 and the connective tissues a clear light 

 blue. No attention should be jxiid, while 

 differentiating, to any of the structures 

 (such as the gonad) which by this method 

 acc}uire a violet coloration. The process 

 should be controlled only by apparent 

 contrast between the pure blues and pure 

 reds in the section. 



The stains used in this preparation are 

 alkali-sensitive, and it is a customarj' pro- 

 cedure in Europe to mount them in as 

 acid a medium as possible. If one is using 

 one of the synthetic resins, which are 

 neutral, it is strongly recommended that 

 the coversUp, before being applied to the 

 resin, be dipped briefly in a strong solution 

 of salicylic acid in xylene. This salicyhc 

 acid will then dissolve in the resin and pro- 

 vide a permanently acid environment. 



13.41 METHODS EMPLOYING THE ACID FUCHSIN-PHOSPHOMOLYBDIC REACTION 



Waterman 1937 (20540b, 12 :21) recommends that dioxane be substituted for ale. in 

 the dehydration of sections stained by these techniques. Kemohan 1934 (4349, 13 :82) 

 mordants formaldehyde material 4 days in ADS 12.1 Weigert 189(3 followed by 2 days 

 in ADS 12.1 Weigert 1891. 



13.41 Bensley test. 1938 Mallory cil. Warren IMallory 1938, 210 



REAGENTS REQUIRED: A. DS 22.21 Altiiiann 1890 (sol. .4); B. 1% phosphomolybdic acid; 



C. water 100, orange G 2, anilin blue 0.5 

 method: [sections] —> water — > .4, 10 niins. -> rinse -^ B, 10 niins. -^ quick rinse — > C, 



1 hr. -^95% ale. till color clouds cease —> balsam, via usual reagents 



13.41 Dupres 1935 14425,46:77 



REAGENTS HEQiiRED: .4. DS 11.43 Gallcgo 1919; B. water 50, acetic acid 25, 40% formal- 

 dehyde 20; C. 1% phosphomolybdic acid; D. water 100, oxalic acid 4, toluidine blue 

 0.25, orange G 4 

 method: [sections of F 3670.0010 Iluffini 1927 material] — > A, 1-10 mins. -^ B, wa.sh — » 

 rinse —' C, 10 mins. -^ wash -> D, 1-2 mins. — > blot — > 95% ale, till differentiated -+ 

 balsam, via usual reagents. 

 note: For toluidine blue in D above there may be substituted cither methylene blue 

 0.3 or malachite green 0.2 or methyl green 0.3. 



