28P IlsFLAMMATION, REGENERATION, GROWTH 



ino- or polyamino-acids in a liter of pus, which may depend on their 

 havinof been eitlier absorbed or transformed into ammoninm com- 

 pounds. From the nucleoproteins purine bodies are formed and may 

 be found in the pus. The relation of the purine bases to local leuco- 

 cytosis is shown by Heile,"^ who found in cold tuberculous abscesses 

 a proportion of purine bases equal to 0.5 per cent., in similar ab- 

 scesses after injection of iodoform, 1.57, and in acute suppuration, 

 10.7. Spermin crystals are also occasionally found in old pus col- 

 lections.'^^ Free fatty acids and volatile fatty acids, such as butyric, 

 lactic,"^ valerianic, and formic, have been found. Products of bac- 

 terial activity, such as bacterial proteins and pigments (e. g., pyo- 

 cyanin), may also be present. It is probable that in many instances 

 these autolytic products are bactericidal, and thus help to terminate 

 the infection. Direct tests have shown that the autolysate of fibrin is 

 bactericidal for staphylococci and streptococci.'^ See also discussion 

 of "Autolysis of Exudates" (Chap. iii). 



All the numerous enzymes of the blood plasma, the leucocytes and 

 the tissue-cells are present in pus. Tluis Achalme *° found evidence 

 of the presence of the following enzymes in pus : proteolytic en- 

 zymes,®^ lipase (splitting monobutyrin), diastase, rennin (coagulating 

 milk), gelatinase, catalase, and oxidase, the last being very abundant. 

 These seem to exist chiefly in the leucocytes, the pus serum being 

 quite free from them. No evidence could be found of enzymes act- 

 ing on amygdalin, saccharose, inulin, or lactose. Fibrin ferment is 

 said to be absent from pus, which is quite surprising in view of the 

 fact that this enzyme is generally considered as being derived chiefly 

 from the leucocytes. Presumably the bacteriolytic "endolysins" of 

 the leucocytes are also present in pus. 



SPUTUM S2 



The chemistry of sputum may be properly considered in this con- 

 nection. In reaction, sputum is ordinarily alkaline, but in case of 

 marked bacterial decomposition in cavities the reaction may become 

 acid. Its specific gravity varies from 1.008 to 1.026, usually varying 

 directly witli the number of leucocytes ; the average specific gravity 

 is about 1.013. The greenish color frequently observed depends gen- 

 erally upon blood-pigment (except in case of icterus), although in 



77 See Williams, Boston IMcd. and Sip-ct. Jour., 1901 (14,5), 355. 



78 d-lactic acid is a constant constituent of pus from the pleura (Ito, Jour. 

 Biol. Chem., 11116 (26), 173). 



70 Bilancioni, Arch, di Farmac<d., 1911 (11), 491. 

 soCompt. Rend. Soc. Biol., 1S99 (.51), 56S. 



81 Concerning proteolytic enzvmes of pus see Opie, Jour. Expor. Med.. 1906 (8), 

 410. 



82 Complete hihlio^aphv given hv Ott, "Cliem. Patiiol. dcr Tubprc," Berlin, 

 1903; lalk, Krgehnisse Plivsiol., 1910 (9), 406: Plesch, Handb. d. Biochem., 1908 

 (HI (1) ), 7. 



