AMYLOID 347 



disintegration. The origin of the normal cell cholesterin is 

 unknown. According to Stadelmann, 1 that which enters with the 

 food is not absorbed, hence the considerable amounts that are 

 constantly being thrown out by the bile and the sebaceous 

 glands must be replaced by cellular activity. Cholesterin is 

 generally considered, but without convincing proof, to be a 

 product of proteid decomposition ; if this is true, then the 

 cholesterin found in disintegrating tissues may be formed from 

 the cell proteids during their decomposition. 2 Apparently 

 cholesterin crystals may be slowly removed, the chief factor 

 probably being the giant-cells that are often found surrounding 

 them. 3 In general they behave as inert foreign bodies. 



AMYLOID 4 



Virchow, in 1853, made the first study of the nature of the 

 substance characteristic of " lardaceous " degeneration, and 

 considered it to be a sort of animal cellulose, because it often 

 became blue if treated with iodin followed by sulphuric acid. 

 To this resemblance in staining reaction we owe the unfortunate, 

 misleading, but generally used, name amyloid. 5 It was but a 

 few years (1859) before Friedreich and Kekule* showed that 

 the substance in question was of proteid nature ; their methods 

 were very crude, but the main fact was soon better substan- 

 tiated by Kiihne and RudnefF (1865). Krawkow, 6 however, 

 in 1897 gave us the first good idea of the composition of amy- 

 loid substance through his amplification of Oddi's 7 observation 

 that amyloid organs contain chondroitin-sulphuric acid, finding 

 that amyloid is a compound of proteid with this acid, similar to 

 nucleoproteid, which is a compound of nucleic acid and proteid. 



1 Dissert., Freiburg in der Schweiz, 1 898. 



2 Of historical interest is Austin Flint's idea that cholesterin 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 cholesterin 

 is not toxic. 



3 See LeCount, Jour. Med. Research, 1902 (7), 166. 



* General literature to 1893, see Wichmann, Ziegler's Beitr., 1893 (13), 487 ; 

 also Lubarsch, Ergeb. allg. Path., 1897 (4), 449 ; modern ideas are summed up 

 in a discussion in the Verb. Deut. Path. Gesellsch., 1904 (7), 2-51. 



5 In view of the fact that this substance is chemically related to chondrin, 

 and that it also closely resembles this substance physically, it has seemed to 

 the writer that the name "chondroid" would be much more appropriate than 

 any of the many more or less misleading and inappropriate titles that are at 

 present in use. The very multiplicity of these terms, however, prohibits any 

 attempt to introduce still another. A particularly unfortunate source of con- 

 fusion exists in the use of the name amyloid for a vegetable substance, formed 

 by the action of acids upon cellulose. 



6 Arch. exp. Path. u. Pharm., 1897 (40), 196. 



7 Ibid., 1894 (33), 377. 



