AUERBACH'S PLEXUS 



26 



AZURE DYES 



vented by immersing the Auer bodies in 

 an aqueous solution of lanthanum ace- 

 tate for 2 hours prior to exposure to the 

 enzyme. Wright's stain may be used to 

 demonstrate the basophilic properties 

 of the Auer rods. Auer bodies are not 

 demonstrable following the Bauer- 

 Feulgen, Lugol's aqueous iodine, Go- 

 mori acid and alkaline phosphatase and 

 lipase reactions. 



Auerbach's Plexus. Supravital staining 

 by injecting methylene blue through 

 the aorta is apparently improved by 

 addition of hydrogen acceptors. Scha- 

 badasch, A., Bull. d'Hist. AppL, 1936, 

 13, 1-28, 72-89, 137-151 advises 0.03- 

 0.05 gm. per liter of p-amidophenol, 

 0.02-0.07 of p-phenylenediamine, 0.02- 

 0.05 of pyrocatechine or 0.05-0.9 of 

 resorcin. The methylene blue must be 

 of high quality and free from metallic 

 salts. He obtained in 5 min. intense 

 staining of the plexus in a cat which re- 

 ceived 1200 cc. of fluid of the following 

 concentration : aq. dest., 1000 cc. ; NaCl, 

 7 gm. ; resorcin, 0.15 gm. and methylene 

 blue (chlorzink free, Hoecht) 0.2 gm. 



Aural Smears, see Ear Smears. 



Auramin (CI, 655) — canary yellow, pyok- 

 tanin yellow, pyoktaninum aureum — 

 This basic diphenyl methane dye may 

 be of use in fluorescence microscopy. 

 Auramine O is Commission Certified. 

 It is one of the substances which arrests 

 mitosis in the metaphase, an action 

 which has been carefully studied by 

 Ludford, R. J., Arch. f. Exper. Zellf., 

 1935-6, 18, 411-441. Tubercle bacilli 

 treated with auramin give golden yellow 

 fluorescence (Hageman, P. K. H., 

 Munch. Med. Woch., 1938, 85, 1066). 



Aurantia (CI, 12) — imperial yellow — An 

 acid nitro dye employed in Champy- 

 Kull method. Aurantia is explosive 

 and it can cause severe dermatitis. 

 All those using it should be warned of 

 the danger. 



Aurin or rosolic acid (CI, 724). 



Autoradiography, see Radioactive Isotopes. 



Axenfeld Reaction. Giroud (A., Proto- 

 plasma, 1929, 7, 72-98) : Add to prepara- 

 tion few drops of formic acid, then 3-4 

 drops 0.1% aq. gold chloride and heat 

 slowly. A rose color appears, then vio- 

 let. Lison (p. 129) says that the reaction 

 is very little characteristic of proteins 

 since analogous reactions are given by 

 creatine, urea, uric acid, glycogen. Its 

 employment is contraindicated. 



Axis Cylinders. These are the cytoplasmic 

 cores of the nerve fibers. Mitochondria 

 can often be seen in them unstained 

 and after supravital coloration with 

 Janus Green. The best method to 

 demonstrate mitochondria in fixed tis- 

 sues is Anilin Fuchsin Methyl Green 



after Regaud fixation. Silver methods 

 show Neurofibrils. Alzheimer's modi- 

 fication of Mann's eosin-methyl blue 

 method is recommended to show early 

 degenerative changes . De Renyi , G . S . , 

 Cowdry's Special Cytology, 1932, 3, 

 1370-1402 has fully described use of 

 methods of microdissection. See Ama- 

 ranth. 



Azan Stain, see Heidenhain's. 



Azidine Blue 3B, see Trypan Blue. 



Azidine Scarlet R, see Vital Red. 



Azins. Azin dyes are those formed from 

 phenazin. Two benzene rings are joined 

 by 2 nitrogen atoms forming a third ring. 

 Examples : amethyst violet, azocarmine 

 G, indulin alcohol and water soluble, 

 Magdala red, neutral red, neutral violet, 

 nigrosin water soluble, phenosafranin, 

 safranin O. 



Azo Blue (CI, 463) — benzoin blue R and 

 direct violet B — This acid dis-azo dye 

 is one of those microinjected vitally 

 into cytoplasm against the nucleus of 

 amebae to ascertain whether the nucleus 

 can be vitally colored (Monn6, L., 

 Proc. Soc. Exp. Biol. & Med., 1934-35, 

 32, 1197-1199). Butt, E. M., Bonynge, 

 C. W. and Joyce, R. L., J. Inf. Dis., 

 1936, 58, 5-9 report that azo blue can 

 be substituted for India ink in the nega- 

 tive demonstration of capsular zones 

 about hemolytic streptococci. 



Azo-Bordeaux, see Bordeaux Red. 



Azocarmine G (CI, 828) — azocarmine GX, 

 rosazine, rosindulin GXF — This basic 

 azin dye is used in place of acid fuchsin 

 in Heidenhain's Azan stain. Azocar- 

 mine B is CI, 829. 



Azocarmine GX, see Azocarmine G. 



Azo Dyes. Chromophore — N=N — uniting 

 naphthalene or benzene rings. See 

 Mono-azo, Dis-azo and Poly-azo Dyes. 

 Lipophilic substitutions in, and slight 

 curative effect claimed in tuberculosis 

 and leprosy (Bergmann, E., Haskelberg, 

 L. and Bergmann, F., J. Am. Chem. Soc, 

 1941,63,2243. 



Azo-fuchsin. Seven are recognized in the 

 Colour Index. Acid mono-azo dyes re- 

 lated to Bordeaux red and orange G. 



Azolitmin, see Hydrogen Ion Indicators. 



Azophloxine G. A. — Fast crimson GR., 

 Amidonaphthol G— an acid Azo dye. 



Azo Reaction for phenols. Formation of 

 azo color by action of diazonium salt on 

 tissue phenol (Lison, p. 140). See 

 Lison, L., C. Rend. Soc. de Biol., 1933, 

 112, 1237-1239). 



Azo Rubin, see Amaranth. 



Azure Dyes. These are basic thiazin stains 

 of great usefulness. The description 

 given by Conn (pp. 76-80) should be 

 consulted. It is here summarized. 

 Azure I (Giemsa) is a trade name for a 

 secret preparation apparently a variable 



