OPDYKE 



243 



ORGAN CULTURE IN VITRO 



Andrew, W. (J. Gerontol., 1949, 4, 95- 

 103). 

 Opdyke, see Keratohyalin Granules, Sepa- 

 ration and Analysis. 

 Opsonocytophagic Index, method for rapid 

 staining of blood smears in (Bondi, A. 

 Jr., J. Lab. & Clin. Med., 1941, 26, 1811). 

 Derivation of index number in (Foshay, 

 L., LeBlanc, T. J., J. Lab. & Clin. Med., 

 1936-37, 22, 1297-1300). 

 Opal Blue (CI, 689)— Aniline Blue, alcohol 

 soluble, Bleu Lumiere, Gentiana Blue 

 6B, Spirit Blue— a basic dye of light 

 fastness 3, to be employed in contrast 

 staining with Biebrich Scarlet, Crocein 

 Scarlet and other dyes (Emig, p. 50)_. 

 Optic Lens, methods of microincineration 

 and histospectrography as applied to 

 cataracts of various sorts and normal 

 lenses with special attention to copper, 

 zinc and iron (Busnel, R. G., Pillet, P. 

 and Tille, H., Bull. d'Hist. AppL, 1938, 

 15, 99-109). 



Oral Mucosa. Smear method for study of 

 keratinization (Weinmann, J., J. Dent. 

 Res., 1940, 19, 57-71). With end of 

 agate spatula gently scrape area about 

 1.5 sq. cm. Smear on slide, dry in air 

 and stain for 30 sec. in : sat. ale. gentian 

 violet (or better crystal violet) 10 cc. + 

 5% aq. phenol, 90 cc. Lugol's Iodine, 

 30 sec. Wash in water until no more 

 color is extracted. Counterstain for 

 2 min. in sat. safranin O in 95% alcohol, 

 10 cc. + aq. dest., 100 cc. Wash in 

 water 2-3 sec, dry and mount in balsam. 



Orange I (CI, 150). Synonyms: naphthol 

 orange, tropaeolin G or 000 No. 1. An 

 acid mono-azo dye used as an Indicator. 



Orange II (CI, 151). Synonyms: acid 

 orange II, Y or A, gold orange, mandarin 

 G, orange A, P, or R, orange extra, 

 tropaeolin 000 No. 2. An acid mono- 

 azo dye. Ebbinghaus, H., Centralbl. 

 f. allg. Path. u. Path. Anat., 1902, 13, 

 422-425 employed gold orange with 

 hematoxylin as a special stain for keratin. 



Orange III, see Methyl Orange. 



Orange A, P, or R, see Orange II. 



Orange Extra, see Orange II. 



Orange G (CI, 27). Synonym; wool orange 

 2G. Of slightly different grade ac- 

 cording to Conn (p. 47) are orange GG 

 and GMP. An acid mono-azo dj'e 

 widely used. 



Orange MNO or MN, see Metanil Yellow. 



Orange R (CI, 161), an acid monoazo dye of 

 light fastness 3-4 action of which on 

 plant and animal tissue is described 

 (Emig, p. 33). 



Orange RR, see Oil Red O. 



Orcein (CI, 1242) is a natural dye produced 

 from lecanora parella (a lichen) and 

 should not be confused with orcin pro- 

 duced from the same plant. It is now 

 prepared synthetically. Its precise for- 



mula remains to be determined but it 

 is a most valuable stain for Elastic 

 Fibers. Mollier, G., Zeit. f. wis. mikr., 

 1938, 55, 472-473 employed it with iron 

 hematoxylin, naphthol green B and 

 azocarmine G. Acetic-orcein is advo- 

 cated as a new stain-fixative for chromo- 

 somes (LaCour, L., Stain Techn., 1941 

 16, 169-174). An acid orcein Giemsa 

 is described for use in dermatology by 

 Pinkus, H., Arch. Dermat. and Syph., 

 1944, 49, 35.5-356. 



Orceille, a purple dye, derived from Lichens 

 growing on the rocks of the Near East 

 and Mediterranean areas, achieved 

 great favor among the ancients being 

 said by Theophrastus and Dioscorides 

 to even excel Tyrian Purple. A Floren- 

 tine dye trader, P^ederigo, promoted 

 this dye, built up a thriving business and 

 calling himself Orcelli, founded a large, 

 distinguished and prolific family (Leg- 

 gett, W. F., Ancient and Medieval 

 I)3^es. Brooklyn: Chemical Publishing 

 Co., Inc., 1944, 95 pp.). 



Organ Culture in Vitro — Written by Honor 

 B. Fell, Strangeways Research Labora- 

 tory, Cambridge, England. June 8, 

 1951 — In most forms of tissue culture, 

 the investigator is not concerned with 

 the original tissue fragment but with 

 the cells which migrate from it and 

 multiply in the medium to form a zone 

 of new growth. The object of "organ 

 culture" is to grow tissue in a differen- 

 tiated state as an independent organ- 

 ism. 



There are several variations of the 

 method, but in general the e.\plants 

 are grown on the surface of a fairly 

 large volume of culture medium with 

 an abundant air supply. Tissue ex- 

 tracts used in the preparation of the 

 medium are never made from young 

 embryos, as such extracts have been 

 shown to inhibit differentiation 

 (Gaillard, P. J., Hormones regulating 

 growth and differentiation in embryonic 

 explants. Act. Sci. et Industr., Paris: 

 Hermann et Cie, 1942). The tissue 

 fragments are transplanted at frequent 

 intervals, partly to restrict outgrowth 

 which disintegrates the histological 

 structure of the explants, and partly 

 because the compact mass of tissue soon 

 exhausts the food material in its im- 

 mediate neighborhood. 



Although as j^et the method is prac- 

 ticed in a few laboratories only, many 

 different types of differentiated tissues 

 have successfully been grown (Fell, 

 H. B., J. Roy. Micr. Soc, 1940, 60, 95- 

 112; Chapter on "Histogenesis in Tissue 

 Culture" in Bourne, G. H., Cytology 

 and Cell Physiology, Oxford: Clarendon 

 Press, 1951). Brachet, A. (C. R. Acad. 



