NEUTRAL RED IODIDE 



228 



NEW METHYLENE BLUE 



of lymphosarcoma ta (Hu, C. H. and 

 Pai, H. C, Arch. Path., 1942, 34, 106- 

 116). 



Neutral Red Iodide. This is a special form 

 of neutral red prepared by Phillips, 

 M. and Cohen, B., Stain Techn., 1927, 

 2, 17-18 and recommended by Sabin 

 for the Neutral Red Janus Green 

 method. 



Neutral Safranin, or Safranin-acid violet 

 (Bensley, R. R., Am. J. Anat., 1911, 

 12, 297-388). Make the neutral dye 

 by precipitating sat. aq. safranin O 

 with sat. aq. acid violet. The latter is 

 added slowly and the mixture is agitated 

 gently. The precipitation should be 

 complete so that when it settles the 

 supernatant fluid is of a faintly violet 

 color. Filter and dissolve dried ppt. 

 in abs. ale. Dilute this stock solution 

 with equal vol. aq. dest. allow to stain 

 30 min. before use. Stain sections, 

 fixed as described under Neutral Gen- 

 tian, in the same way as with neutral 

 gentian. Nuclei are colored with safra- 

 nin and secretion antecedents with the 

 acid violet. The method has been used 

 chiefly for the pancreas but it gives fine 

 coloration of nerve as well as gland cells. 

 Unfortunately the colors are not very 

 permanent. 



Neutral Stains. As explained by the 

 Bensleys (p. 65) acid and basic dyes 

 are mutually antagonistic. One will 

 extract the other from a section. This 

 can be overcome by having them react 

 on each other to form a molecularly 

 balanced neutral compound insoluble 

 in pure water and which must therefore 

 be employed in alcoholic solution. 

 Because the staining depends upon the 

 hydrolytic splitting of the compound 

 they must be applied at maximum con- 

 centration of water consistent with 

 retaining the dye in solution. It is on 

 account of the necessity for dilution 

 with water to promote dissociation that 

 water is added to Wright's blood stain 

 on the slide. These neutral dyes are 

 of particular value in the staining of 

 secretion antecedents by R. R. Bensley 

 and his followers, see Neutral Gentian 

 (gentian violet-orange G), Neutral 

 Safranin (safranin-acid violet). Crystal 

 Violet-Acid Fuchsin and Bowie's Stain. 



Neutrophile Leucocyte (finely granular 

 leucocyte, polymorphonuclear leuco- 

 cyte). Most numerous granular leuco- 

 cyte, percentage 55-75; slightly smaller 

 (9-12m) than eosinophile; nucleus lo- 

 bated, usually also filamented, stains 

 deeply; specific granules, refractile, 

 neutrophilic, small, uniform and 

 numerous; highly motile and phago- 

 cytic. Special methods for their study 

 are far too numerous even to list. 



The so-called toxic neutrophiles in 

 certain pathological states differ from 

 normal ones in the staining of nuclei 

 and specific granules (Mommsen, H., 

 Ztschr. exper. Med., 1929, 65, 299). 

 A comprehensive account of neutro- 

 philes is provided by Bunting, C. H. 

 m Downey's Hematology, 1938, 1, 

 160-177. Because these cells normally 

 constitute by far the majority of leuco- 

 cytes in the circulating blood, chemical 

 analyses of total leucocytes separated 

 from the erythrocytes relate chiefly to 

 them. The most convenient way is to 

 mix fresh blood with Anticoagulant, 

 centrifuge and take the so-called buffy 

 layer. For lipid analysis of such 

 material, see Boyd, E. M., Arch. Path., 

 1936, 21, 739-748. Another useful 

 method, described by Haan and em- 

 ployed by Barnes, J. M., Brit. J. Exp. 

 Path., 1940, 21, 264-275, which works 

 nicely with the rabbit but poorly with 

 the cat, is to inject intraperitoneally 

 200-300 cc. warm sterile saline solution 

 and 4 hrs. later to withdraw fluid with a 

 cannula into 5 cc. 4% sodium citrate. 

 This fluid contains 95-98% neutrophiles. 

 Barnes has outlined methods for de- 

 termination of Cathepsin, Nuclease, 

 Amylase, Lipase, Lysozyme and Adeno- 

 inase. Since it is possible now to break 

 up cells and to collect by centrifugation 

 masses of Mitochondria and Nuclei, 

 it should be feasible to collect and 

 similarly to analyse the neutrophilic 

 granulations. For technique of meas- 

 uring motility, chemotaxis and other 

 properties, see Leucocytes. 



Neutrophilic, see Staining. 



Nevillite V and No. 1 have been compared 

 with gum damar and Canada balsam as 

 mounting media by Groat (R. H., 

 Anat. Rec, 1939, 74, 1-6). Both are 

 clean, colorless, inert and neutral. 

 He recommends a 60% solution of 

 either V or No. 1 in toluol. 



New Blue R, see Naphthol Blue R. 



New Fuchsin (Magenta III) (CI, 678)— 

 fuchsin NB, isorubin — It is triamino- 

 tritolyl-methane chloride. This new 

 fuchsin is sometimes specified for 

 staining of acid fast bacilli. 



New Methylene Blue. The Colour Index 

 lists several dyes by this name of which 

 2 deserve mention: (1) GG (CI, 911) 

 is recommended by the Bensleys (p. 

 16) as a supravital stain for mast cells 

 and for the thyroid because of its meta- 

 chromatic capacity. (2) N (CI, 927)— 

 methylene blue NN— Conn (p. 88) 

 says that it may be of some value though 

 it is practically never used in micro- 

 scopical work. Cowdry tried it and 

 found that it had no particular ad- 

 vantages. 



