LENGTH 



175 



LEUCOCYTES 



2. Leptospira (Noguchi, 1924). 0.9% 

 aq. sodium chloride, 800 parts; fresh 

 rabbit serum, 100 parts; 2% nutrient 

 agar pH 7.2, 100 parts, rabbit hemo- 

 globin solution 10-20 parts. (To make 

 this hemo'^^lobin solution take 1 part 

 defibrinated rab!)it's blood and 3 parts 

 aq. dest., centrifuge and use clear super- 

 natant fluid.) Tube, prove sterility by 

 incubation before using. Subculture 

 every 30 days. An increase in hemo- 

 globin solution improves growth of 

 Leishmania. 



3. Adler's modification of above. 

 Agar, 1 part; Locke's solution contain- 

 ing 0.2% dextrose, 8 parts; fresh rabbit 

 serum, 1 part. For species of Leish- 

 mania and Trypanosoma cruzi. 



4. Modified, Salle and Schmidt 

 (Cleveland and Collier, 1930). Veal 

 infusion (50 gm. Bacto-veal, Difco -t- 

 1000 cc. aq. dest.), 250 cc; proteose, 

 peptone (Difco), 10 gm.; sodium chlo- 

 ride, 5 gm.; aq. dest., 550 cc. Dissolve 

 make pH 7.4 and autoclave. Add 20 cc. 

 50% aq. glucose (sterilized by filtration 

 or in autoclave 10 lbs., 10 min.) and 

 60 cc. horse red cells laked with 2 parts 

 aq. dest. Pour in medium flasks or 

 tubes. Vigorous long lived cultures. 



Length measurements : 



Millimeters to inches X 0.0394. Inches 

 tomm. X25.4. SeeMicron. 



Lens Paper, a specially prepared soft paper 

 indispensible for cleaning immersion 

 oil from objectives. 



Leprosy Bacilli. Stain by carbol-fuchsin in 

 smears. See Concentration method for 

 collecting bacilli from lesions. For 

 study in sections, see Acid Fast Bacilli. 



Leptospira Medium, Noguchi's, see Leish- 

 mania. 



Leptospiras, method for isolation from water 

 (Bauer, J. H., Am. J. Trop. Med., 1927, 

 7, 177-179. See Spirochetes. 



Leuco Basic Fuchsin. To make add to 200 

 cc. aq. sol. fuchsin, 2 gm. potassium 

 metabisulphite and 10 cc. N hydro- 

 chloric acid. After bleaching 24 hrs. 

 add 0.5 gm. Novit, shake 1 min. and filter 

 through coarse paper. Resulting clear 

 solution works nicely in Feulgen tech- 

 nique (Coleman, L. C, Stain Techn., 

 1938,13, 123-124). 



Leuco-Dyes as vital stains. Make 001% 

 aq. solutions of methylene blue,azurA, 

 thionin toluidine blue and brilliant cresyl 

 blue. Add to 100 cc. 1-2.5 cc. N/10 

 NajSaO, and 1-4 cc. N/10 HCl. Mix 

 and store at room temperature in dark. 

 To stain, add 1-2 drops of leucobase to 

 the protozoa, blood cells, etc. in physio- 

 logical saline. Said to give good contrast 

 staining of nucleus and cytoplasm and 

 to be useful in oxidation-reduction 

 determinations (Roskin, G., Arch. Russ. 



Anat. Hist. Embr., 1937, 16,107-109). 



Leuco-Patent Blue V, see Lillie, p. 285. 



Leucocytes. In the broad sense they in- 

 clude all white blood cells but the term 

 is generally restricted to the "granular" 

 leucocytes as compared with the "non- 

 granular" ones (Lymphocytes and Mon- 

 ocytes). In a still narrower sense the 

 leucocytes include only polymorphonu- 

 clear neutrophiles, eosinophiles and 

 basophiles which are easily found in 

 circulating blood as contrasted with less 

 differentiated leucocytes called Myelo- 

 cytes and Myeloblasts generally con- 

 fined to the bone marrow. 



For mitochondria within leucocytes 

 supravital staining with Janus green is 

 indicated. In smears Giemsa's stain 

 has a little advantage over Wright's in 

 the fact that it better demonstrates any 

 bacteria that may be present. The 

 May-Giemsa technique is most used in 

 Europe. It is, in effect, a double staining 

 because the air dried smears are first 

 treated with the May-Grunwald com- 

 bined fixative and stain and are later 

 colored by Giemsa's stain. It gives 

 satisfying deep colors. TheKardos- 

 Pappenheim modification is suggested 

 when a particularly intense coloration of 

 neutrophilic granules is desired. Ehr- 

 lich's triacid stain may likewise be use- 

 ful because it is said to stain the neutro- 

 philic granules leaving the azur granules 

 untouched. 



Leucocytes give strong Peroxidase 

 and Oxidase reactions, which are, how- 

 ever, not specific for them. The Golgi 

 Apparatus (reticular material) can be 

 demonstrated by long treatment with 

 osmic acid or by the Cajal uranium ni- 

 trate and silver method (Cowdry, E. V., 

 J. Exper. Med., 1921, 33, 1-11). The 

 demonstration of degenerative leucocytic 

 changes associated with ageing is de- 

 scribed by Lowell (A. L., J. Lab. & Clin. 

 Med., 1937-38, 23, 791-796), of variability 

 in relation to alterations in meteorologic 

 conditions by Berg (M., J. Lab. & Clin. 

 Med., 1937-38, 23, 797-803) and of lipoid 

 components by Bacsich (P., J. Anat., 

 1935-36, 70, 267-272). Chemotaclic re- 

 sponse and motility can be measured 

 both in tissue cultures (Comau, D. R. 

 Arch. Path., 1940, 30, 896-901) and 

 directly by observing the behavior of 

 leucocytes with relation to bacteria and 

 in temporary mounts (Mallery, O. T. 

 and McCutcheon, M., Am. J. Med. Sci., 

 1940, 200, 394-399 ) . By the latter method 

 differences in behavior of neutrophiles 

 from seriously ill and normal persons 

 have been reported . Motion pictures are 

 of great assistance in making a thorough 

 analysis of the movements and behavior 

 of leucocytes. Some excellent ones, 



