408 BLOOD AND GLANDS 



887. Elective Staining of Erythrocytes (K. Okajima, Anat. 

 Rec, xi, 1917). This stain is based on the fact that the phos- 

 phomolybdic acid lake of the ahzarin stains, shows a special 

 affinity for haemoglobin. Fix material in formol, sublimate, 

 chrome, etc. Transfer sections on slide to aq. dest. ; mordant 

 in 10 per cent, phosphomolybdic acid solution for thirty seconds 

 to two minutes ; wash in water ; stain in this mixture for twenty 

 minutes to twenty hours : sodium sulfalizarinate saturated 

 aqueous solution, 100 c.c. ; and 10 per cent, phosphomolybdic 

 acid aqueous solution, 30 c.c. (10 to 50 c.c.) ; wash in water ; 

 alcohols, xylol, balsam. Erythrocytes go bright yellow-orange. 

 Counter-staining may be done in Ehrlich's hsematoxylin. 



The " specificity " of this method is open to doubt, but it 

 gives interesting results. See also Lepehne {Zeigl. Beitr., Ixv, 

 1919, p. 183). 



888. Microchemical Tests for Oxidation Centres in the Cell. 

 Recently certain workers have claimed to be able to locate centres 

 or regions of oxidation in the cell by means of some substance 

 sensitive to free oxygen. Unna's method is to use a solution of 

 rongalit white, which is a solution of the leucobase of methylen 

 blue kept in a state of reduction by excess of rongalit, an absorp- 

 tion product of formaldehyde with sodium sulphite. See Unna 

 {Arch. f. mikr. Anat., Ixxviii, 1911 ; ibid., Ixxxvii, 1915, p. 96) ; 

 also HiRSCH and Buchmann (Z. Zellforsch., ii, 1930, p. 255). 

 Drury {Proc. Roy. Soc, 1914) has shown that Unna's claim is 

 inadmissable and consequently his theory of staining by oxidation 

 and reduction is not proven. Graham {Journ. Med. Res., xxxv, 

 1916) claims to have demonstrated by means of HgO^ and naphthol 

 that the granules of leucocytes and myelocytes contain a per- 

 oxidase of the peroxide type. Two techniques have been 

 developed for the demonstration of these enzymes known as the 

 oxidase and peroxidase tests. The former depends on the 

 synthesis of indophenol blue from a-naphthol and dimethyl-p- 

 phenylen-diamin. Schultz in his oxidase reaction proceeds as 

 follows : Blood and marrow smears fixed in formalin vapour are 

 treated firstly in the a-naphthol solution ; prepared by melting 

 1 grm. of naphthol on the surface of 100 c.c. of aq. dest., and 

 adding potassium hydrate till the naphthol dissolves. After a 

 few minutes in this solution (cooled) the smears are transferred 

 to a 1 per cent, solution of the dimethyl — ^for the same time- 

 when a blue colour is seen to appear where the oxidases lie. 

 Mount in glycerin jelly, but blue colour fades. 



Graff {Zent. allg. Path., xxvii, 1916, p. 313) introduces the 

 following modification which gives preparations permanent for 

 several months, and is applicable to frozen sections : 0-5 grm. 

 a-naphthol is dissolved by boiling in 250 to 300 c.c. of distilled 

 water, and is placed in a brown flask. Excess of a-naphthol 



