MANN'S METHYL BLUE-EOSIN 



146 



MASSON'S TRICHROME 



and mounted. See Alzheimer's Modi- 

 fication of Mann's method. 

 Marchi Method. For degenerating nerve 

 fibers. Modification by Swank, R. L. 

 and Davenport, H. A., Stain Teclin., 

 1935, 10, 87-90. Details provided by 

 Dr. J. L. O'Leary. Degeneration time 

 of approximately 14 to 20 days. Kill 

 animal by overdose of nembutal or some 

 other barbiturate given intraperi- 

 toneally. Open left ventricle, insert 

 cannula into aorta and perfuse with 

 2.5-5% anhydrous (10% crystalline) 

 magnesium sulfate solution containing 

 2-3% potassium bichromate. Imme- 

 diately afterwards remove the brain 

 and spinal cord and put into 10% 

 formalin for 48 hrs. Place slices 3 mm. 

 thick directly, without washing, in : 

 1% aq. potassium chlorate, 60 cc; 

 1% aq. osmic acid, 20 cc. ; glacial acetic 

 acid, 1 cc. ; 37% formaldehyde (Merck's 

 reagent), 12 cc. Use about 15 volumes 

 of this fluid to 1 of tissue. Agitate and 

 turn over daily. After staining for 7-10 

 days, wash in running water, 12-24 hrs., 

 dehydrate in 70% and 95% and absolute 

 alcohol and imbed in low viscosity nitro- 

 cellulose as described by Davenport, 

 H. A. and Swank, R. L., Stain Tech., 



1934, 9, 134-139. See Celloidin Im- 

 bedding. Cut 40^ sections serially, 

 mount on slides, dehydrate to toluol, 

 placing chloroform in absolute alcohol 

 since low viscosity nitrocellulose is 

 soluble in absolute alcohol. Clear in 

 toluol. Mount in clarite X dissolved 

 in toluol. See these authors (Stain 

 Techn., 1935, 10, 45-52) for artifacts 

 and effects of perfusion in Marchi 

 technique. Rasmussen, G. L., Anat. 

 Rec, 1944, 89, 331-338 has elaborated a 

 very useful cellophane strip method for 

 preparation and study of Marchi serial 

 sections. 



Marchi's Fluid. Miiller's Fluid, 2 parts; 

 1% osmic acid, 1 part. Fix 5-8 days; 

 wash in running water. Employed to 

 blacken degenerated nerve fibers. See 

 Nerve Fibers. 



Method, underlying mechanisms in- 

 volved (Swank, R. L. and Davenport, 

 H. A, Stain Techn., 1934, 9, 11-19; 



1935, 12, 45-52). 



Marine Blue V, see Anilin Blue. 



Marino's Stain for malaria plasmodia is de- 

 scribed in detail by Craig, p. 286 who 

 states that it gives excellent results; 

 but, owing to its complexity, is little 

 used for routine blood examinations. 



Marshall Red (British Drug Houses Ltd), 

 a disazo dye. Stain sections in sat. 

 aq. solution 20 min. Rinse in aq. 

 dest. Stain in sat. Victoria Green G 

 in 70% alcohol 30 min. Rinse in 95% 

 alcohol, dehydrate, clear and mount 



in usual way. Myofibrils sage green, 

 nuclei crimson. Advised also for retina 

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

 1941,61,88-94). 



Martius Yellow (CI, 9) — Manchester yellow, 

 naphthol yellow — An acid nitro dye 

 employed by Pianese (G., Beitr. z. 

 Path. Anat. u. Allg. Path., 1896, Suppl. 

 I, 193 pp.) for investigating cancer 

 tissue in association with acid fuchsin. 

 Conn (p. 44) reports good results in 

 staining of plant tissue with CC product. 



Masson's Gelatin Glue. Method for mak- 

 ing sections stick to slides (Masson, 

 P., Am. J. Path., 1928, 4, 181-212). 

 Dissolve 0.05 gm. sheet gelatin in 20 

 cc. aq. dest., warming gently. Filter a 

 large drop on each slide on warm plate. 

 Float paraffin sections on drops. When 

 drops spread place slides upright to 

 drain but do not permit drying. Blot 

 and transfer to dish containing formalin 

 (so arranged that vapor only will act 

 on slides) in oven 45-50 °C. For sub- 

 sequent staining 20 minutes in hot vapor 

 is enough. For silver treatment over- 

 night is suggested. 



Masson's Trichrome. Stain for connective 

 tissue (Masson, P., Am. J. Path., 1928, 

 4, 181-212; J. Tech. Meth., 1929, 12, 

 75-90) . The following is an abbreviated 

 account of the technique as recom- 

 mended by IVIallory (p. 156). Use 5n 

 paraffin sections of Bouin's fluid (3 

 days) or Regaud's (1 day) fixed tissues. 

 Mordant in 5% aq. ammonio-ferric 

 alum previously warmed to 45-50 °C. 

 for 5 min. Wash in water and stain 

 for 5 min. at 45-50°C. in Regaud's 

 hematoxylin (hematoxylin, 1 gm.; 95% 

 ale, 10 cc; glycerin, 10 cc; aq. dest., 

 80 cc). Rinse in aq. dest. and dif- 

 ferentiate in picric alcohol (sat. picric 

 acid in 95% ale, 2 parts; 95% alcohol, 

 1 part). Wash in running tap water. 

 Stain for 5 min. in: acid fuchsin, 0.3 

 gm.; Ponceau de xylidine, 0.7 grn.; 

 aq. dest., 100 cc. ; glacial acetic acid, 

 1 cc. Rinse in aq. dest. Differentiate 

 in 1% aq. phosphomolybdic acid, 5 

 min. Without rinsing add 10 drops sat. 

 aniline blue in 2% acetic acid and leave 

 for 5 min. Rinse in aq. dest. and place 

 again in phosphomolybdic acid. 1% 

 acetic for 5 min. Dehydrate in 95% 

 alcohol, then absolute, xylol and balsam. 

 Collagen, deep blue; neuroglia fibrils, 

 red; nuclei, black; argentaffin granules, 

 black or red. See modifications by 

 Goldner, J., Am. J. Path., 1938, 14, 

 237, and Larson, C. P. and Levin, E. J., 

 Arch. Path., 1940, 29, 272-273. Tech- 

 nique for application of Masson's tri- 

 chrome stain to tissue previously 

 colored with Weigert's resorcin-fuchsin 

 is given by Mendelotf, J. and Blech- 



