TESTIS 



242 



THYMONUCLEIC ACID 



indicated discharge of material from the 

 interstitial cells into the blood stream. 

 Wagner {loc. cit.) has observed some- 

 what similar phenomena in other ani- 

 mals, but there has been no satisfactory 

 follow up. For detailed information 

 about interstitial cells see Rasmussen, 

 A. T., Cowdry's Special Cytology, 1932, 

 3, 1674-1725. 



Testosterone, Pollock, Anat. Rec, 1942, 84, 

 23-27. 



Tetrachrome Blood Stain, see MacNeal's. 



Tetralin is tetrahydronaphthalene used as a 

 clearing agent after Diaphanol. 



Thallium. Barbaglia's Method. Fi.x in 

 95% alcohol iodized. This precipitates 

 thallium in the form of insoluble crystals 

 of thallium iodide recognizable by their 

 yellow color (Lison, p. 66). 



Thiamine. Blaschko and Jacobson (H. and 

 W. in Bourne's Cytology, 1942, p. 196) 

 refer to the work of Ellinger and Kos- 

 chara in the observation under the fluo- 

 rescence microscope of green fluorescence 

 due to flavin and that on alkalinization 

 this is replaced by a bluish fluorescence 

 which is known to be occasioned by the 

 presence of thiamine, itself identical 

 with vitamin B, or aneurin. 



Thiazin Dyes. A very useful group of dyes 

 for the histologist. The two benzene 

 rings are joined by =N— and — S— . 

 Examples : azure A, B and C, methylene 

 azure, methylene blue, methylene green, 

 methylene violet, new methylene blue 

 N, thionin, toluidin blue O. 



Thiazine Red R (CI, 225)— chlorazol pink 

 Y, rosophenine lOB — An acid mono-azo 

 dye employed especially as counterstain 

 for iron hematoxylin. 



Thiazole Dyes contain thiazole ring with 

 indamine as chroma tophore. Geranine 

 G, primalin, thioflavine S, and titan 

 yellow. All of these dyes appear to be 

 useful in fluorescence microscopy. Pick, 

 J., Zeit. f. wis. Mikr., 1935, 51, 338-351 

 refers to three of them. 



Thiazole Yellow, see Titan Yellow. 



Thioflavine S (CI, 816). An acid thiazole 

 dye used in fluorescence microscopy. 



Thionin (CI, 920)— Lauth's violet— Com- 

 mission Certified. An extremely useful 

 basic thiazin dye. See Tissue Baso- 

 philes, King's Carbol Thionin, etc. 



Thiourea. A derivative of urea with sul- 

 phur replacing oxygen. As means of 

 activating thyroid gland (Thomas, O. 

 L., Anat. Rec, 1944, 89, 461-469). 

 Effect on organ weights and plasma 

 proteins of the rat (Leathern, J. H., 

 Anat. Rec, 1944, 89, 540). 



Thorium Dioxide is occasionally employed 

 as a vital stain for reticulo-endothelium. 

 Angermann, M. and Oberhof, K., Zeit. 

 f . Ges. Exp. Med., 1934, 94, 121-126 give 

 directions for its administration to rab- 



bits and for determination of its dis- 

 tribution chemically, radiologically and 

 histologically. (Thorotrast) 



Thulium, see Atomic Weights. 



Thyme Oil N.F. VI. Sometimes misnamed 

 oil of origanum. Contains thymol, car- 

 vacrol, cymene, pinene, linalool and 

 bornyl acetate. It is said to be useful 

 for clearing celloidin sections. 



Thymol Blue. See Hydrogen Ion Indicators. 



Thymonucleic Acid {Feidgen or nucleal reac- 

 tion for). Pass paraffin sections, fixed 

 in equal parts sat. aq. corrosive subli- 

 mate and absolute alcohol , through xylol 

 and alcohols to water. Place in a stain- 

 ing jar containing normal HCl (82.5 cc. 

 HCl, sp. gr. 1.17-1.185 per liter of water) 

 at room temperature for 1 min. Trans- 

 fer to normal HCl, at 60°C. and there 

 hydrolyze for 4 min. Treat with the 

 fuchsin sulphurous acid reagent in a 

 staining jar for ^1 hr. (This reagent 

 is : One gram of basic fuchsin is dis- 

 solved in 100 cc. of distilled water with 

 the aid of a little heat. The solution is 

 filtered while still warm and 20 cc of 

 normal HCl is added to the filtrate. The 

 resulting fluid is then cooled and 1 

 gm. dry sodium bisulfite (NaHSOs) is 

 added. Then, after standing for about 

 24 hrs., the reagent is ready for use and 

 should have a pale straw color.) Pass 

 through a series of 3 jars, each contain- 

 ing a solution made by adding 10 cc. of a 

 molecular solution of sodium bisulfite 

 (i.e., 104 grams per liter) to 200 cc. of 

 tap-water, allowing 1§ min. in each and 

 agitating frequently. Wash in tap 

 water for 5 min., dehydrate, clear and 

 mount in balsam. Thymonucleic acid 

 is colored purple or violet and color 

 holds (Cowdry, E. V., Science, 1928, 

 68, 40-41). Collected references (Milo- 

 vidov, P., Protoplasma, 1938, 31 (2), 

 246-266) ; technique for plant tissues 

 (Whitaker, T. W., Stain Techn., 1939, 

 14, 13-16). A more recent account is 

 given by Stowell, R. E., Stain Techn., 

 1945, 20, 45-58. Specificity has been 

 considered by Dodson, E. O., Stain 

 Techn., 1946, 21, 103-105. See Bauer- 

 Feulgen stain for Glycogen. 



Dr. A. R. Gopal-Ayengar of the 

 Barnard Free Skin and Cancer Hospital 

 has supplied details of a modification 

 of the Feulgen technique by Rafalko, 

 J. S., Stain Techn., 1946 21, 91-93. In- 

 stead of using HCl and sulphites, as in 

 the usual method, Rafalko directly 

 charges both basic fuchsin and the 

 bath water with SO2 gas, using N HCl 

 only for the necessary process of hy- 

 drolysis. By this method, he claims to 

 have been able to stain diffuse and small 

 chromosomes, which give negative 

 results with conventional procedure. 



