MALLORY'S CONNECTIVE 



145 



MANN'S METHYL BLUE-EOSIN 



for 4 days and in his secondary mordant 

 — copper acetate, 5 gm.; chromium 

 fluoride, 2.5 gm.; acetic acid (36%), 

 5 cc; aq. dest., 100 cc. and formol, 

 10 cc— for 2 days. Imbed in paraffin 

 in the usual way. 



Rexed, B., and Wohlfart, G., Zeit. 

 wiss. Mikr., 1939, 56, 212-215 suggest 

 control of pH of the acid fuchsin. It is 

 stated that fresh 0.1% acid fuchsin has 

 pH 4.49 and that increase in alkalinity 

 makes it defective. To prepare one at 

 pH 3.29 ± 0.01, which is recommended, 

 take acid fuchsin 1 gm.; N/10 HCl, 60 

 cc. ; aq. dest. 900 cc. ; Storensen's citrate 

 (citric acid crystals, 21 gm.; N/1 

 NaOH, 200 cc; + aq. dest. to make 

 1000 cc), 40 cc. Most tissues stain in 

 range pH 3-4, red blood cells alone at 

 pH5-7. 



In 1936, Mallory considered (Stain 

 Tech., 11, 101-102) the most important 

 modifications of his stain to be Heiden- 

 hain's Azocarmine (Azan), the Lee- 

 Brown and Masson Trichrome methods. 

 See Grossman's modification and Pitui- 

 tary for special adaptations. 

 Mammary Glands. These can be studied 

 in sections bj' methods intended to 

 reveal the particular data sought. For 

 general purposes Hematoxylin and 

 Eosin, Mallory's Connective Tissue 

 Stain, or Phloxine-Methylene Blue is 

 recommended after Zenker fixation. 

 For fat use Sudan Black and Oil Red O 

 on frozen sections after fixation in 10% 

 formalin or examine in parafhn sections 

 after fixation in Flemming's fluid or 

 some other osmic acid containing mix- 

 ture. 



In the case of the small glands of mice, 

 rats, rabbits and other mammals the 

 method of making whole mounts is 

 invaluable in investigations of the 

 responses of mammary glands to endo- 

 crine stimulation. The following is 

 essentially the same technique as that 

 oridnally described by Turner, C. W. 

 and Gardner, W. U., Agri. Exp. Res. 

 Stat. Bull., Univ. of Mo., 1931, 158, 

 1-57 : Remove skin and mammary gland. 

 Stretch out and fasten on a cork block 

 with the external surface of the skin 

 down. Fix in Bouin's fluid 24 hrs. 

 Wash in tap water. Dissect away all 

 tissue over the gland which has been 

 tinged light yellow by the picric acid 

 in the fixative. Remove the gland from 

 the skin. Stain in Mayer's Hemalum. 

 Wash in 1% aq. potassium alum and then 

 in water. Differentiate in 70% ale + 

 2% of hydrochloric acid until the color 

 has been removed from the connective 

 tissue and the acini and ducts of the 

 glands show up in sharp contrast in a 

 light background. Wash in tap water. 



Dehydrate in alcohol, clear in xylol, 

 mount in balsam between glass plates 

 and close the edges with sealing wax. 

 Much can be made out when magnified 

 only 2-5 times. Small pieces can be 

 mounted on slides, with edges of cover 

 glasses supported as may be necessary, 

 for examination at higher magnifications. 

 There are many excellent pictures in 

 the paper cited. 



For examination of fetal mice, see 

 Turner, C. W. and Gomez, E. T., ibid, 

 1933, 182, 1-43. Valuable data are 

 given in Turner's chapter on mammary 

 glands in Allen's Sex and Internal 

 Secretions, Baltimore: Williams &Wil- 

 kins, 1939, 1346 pp. For techniques to 

 reveal secretory phenomena in mam- 

 mary glands, see Weatherford, H. L., 

 Am. J. Anat., 1929, 44, 199-281; Jeffers, 

 K. R., Am. J. Anat., 1935, 56, 257-277, 

 279-303. Technique for localizing site 

 of fat formation in mammary glands is 

 given by Kelly and Petersen, J. Dairy 

 Sci., 1939, 22, 7. The differential stain- 

 ing of sections of unpreserved bovine 

 udder tissue is to be found in U. S. 

 Dept. of Agri. Circular No. 514, under 

 authorsliip of W. T. Miller and H. W. 

 Johnson. A method for obtaining 

 serial slices of whole human breasts is 

 described by Ingleby, H. and Holly, C, 

 J. Tech. Meth., 1939, 19, 93-96. 



Manchester Blue (British Drug Houses 

 Ltd), a dis-azo dye of the benzidine 

 series. In either alcoholic or aqueous 

 solution it gives a sharp deep blue 

 effect (H. G. Cannan, J. Roy. Micr. 

 Soc, 1941, 61, 88-94). 



Manchester Brown, see Bismark Brown Y. 



Manchester Yellow, see Martius Yellow. 



Mandarin G, see Orange II. 



Manganese. Histochemical detection un- 

 certain (Lison, p. 98). 



Manganese Dioxide. Drinker, C. K. and 

 Shaw, L. H., J. Exper. Med., 1921, 

 33, 77-98 employed a suspension of fine 

 particles in acacia water to investigate 

 phagocytic power of endothelium be- 

 cause the particles can be seen within 

 the cells and the amounts of manganese 

 in the tissues can be determined by 

 chemical analysis. 



Mann's Fixative is equal parts 1% aq. osmic 

 acid and sat. corrosive sublimate in phys- 

 iological salt solution (0.85% NaC'l). 

 It is a good way to apply osmic acid for 

 the blackening of fat. 



Mann's Methyl Blue-Eosin Stain. This 

 is used for protozoa and for inclusions 

 caused by viruses. Sections are de- 

 paraffinized, stained 12 hrs. in 1% aq. 

 methyl blue 35 cc, 1% aq. eosin 45 cc 

 and aq. dest. 100 cc. They are then 

 rinsed in 95% ale, dehydrated cleared 



