420 RETROGRESSIVE CHANGES 



cholesterol crystals are present, on treatment with five parts concen- 

 trated sulphuric acid and one of water, the edges of the crystals be- 

 come carmine red, then violet. Concentrated sulphuric acid plus a 

 trace of iodin colors the crystals in sequence, violet, blue, green, and 

 red. Hirschsohn^ recommends a reaction with a 90 per cent, solution 

 of trichloracetic acid in HCl, which gives red, then violet, then blue. 

 The results of microchemical examination are said not to agree at all 

 quantitatively with analytic results.*^ 



Since all cells contain cholesterol,^ it is perhaps accumulated as one 

 of the least soluble products of their disintegration. The origin of 

 the normal cell cholesterol is unknown, but that which is liberated by 

 normal disintegration of cells seems to be retained and worked over.^ 

 It is not destroyed during autolysis.^ Cholesterol is generally con- 

 sidered, but without convincing proof, to be a product of protein de- 

 composition; if this is true, then the cholesterol found in disintegrating 

 tissues may be formed from the cell proteins during their decomposi- 

 tion.^'' Apparently cholesterol crystals may be slowly removed, 

 the chief factor probably being the giant-cells that are often found 

 surrounding them,^> and the large "foamy" endothelial cells that 

 take up especially the uncrystallized cholesterol. In general they 

 behave as inert foreign bodies. Xanthomatous masses of various 

 kinds all seem to be composed of deposits of cholesterol esters which 

 lead to proliferative and phagocytic reactions in the fixed tissues.'^ 



Cholesterolemia.^' — Normal blood contains 0.16 to 0.17 per cent. (Gorham 

 and Myers) of cholesterol, of which about 55 per cent, is in the corpuscles, but 

 in pathological conditions the amount in the plasma varies greatly (Bacmeister 

 and Henes)." Cholesterol-rich diet causes a slight increase,'^ but a more marked 

 increase is said to be obtained in pregnancy," nephritis, early arteriosclerosis, 

 obesity, diabetes, and obstructive but not in hemolytic jaundice." According to 

 some observations, in nephritis the amount of cholesterol bears no relation to 

 the albuminuria, and in uremia it may be low; acute febrile diseases usuallj' show 

 a lowered cholesterol, which is unchanged in tuberculosis. Stapp^* describes 



6 Pharm. Centralhalle, 1902 (43), 357. 



« Thavscn, Cent. allg. Pathol, 1015 (2()\ 433. 



7 See Doree, Biochem. Jour., 1909 (4), 72. 



8 Ellis and Gardner, Proc. Royal Soc, London, 1912 (84), 461. 



3 Corper, Jour. Biol. Chem., 1912 (11), 37; Shibata, Biochem. Zeit., 1911 (31), 

 321. 



'" Of historical interest is Austin Flint's idea that cholesterol in the blood is 

 an important factor in intoxications, especially in icterus (Amer. Jour. Med. Sci., 

 1862 (44), 29). All recent evidence is to the effect that cholesterol is not toxic. 



" See LeCount, Jour. Med. Research, 1902 (7), 160; Corper, Jour. Exp. Med., 

 1915 (21), 179; Stewart, Jour. Path, and Bact., 1915 (19), 305. 



12 Literature given by Rosenbloom, Arch. Int. Med., 1913 (12), 395. 



> 3 Bibliography by Dewey, Arch. Int. Med., 1916 (17), 757; Gorham and 

 Myers, Arch. Int. Med., 1917 (20), 599; Pacini, Med. Record, 1919 (94), 441. 



" Deut. med. Woch., 1913 (39), 544. 



" See Luden, Jour. Biol. Chem., 1916 (27), 257. 



1^ The blood of the fetus corresponds closely to that of the mother in respect 

 to free cholesterol but contains no cholesterol esters. (Slemons and Curtis, Amer. 

 Jour. Obst., 1917 (75), 569.) 



" Rothschild and Felson, Arch. Int. Med., 1919 (24), 520. 



"Deut. Arch. klin. Med., 191S (127), 439; corroborated by Epstein, Amer. 

 Jour. Med. Sci., 1917 (154), 638. 



