ATROPHY, DEGENERATION, PIGMENTATION, AND NECROSIS. 83 



cells. These, however, frequently undergo atrophy as the result of 

 pressure from the swollen, degenerated tissue. 



It is not yet known whether amyloid degeneration is due to a direct 

 transformation of the tissue, or is an infiltration of the tissue by some 

 abnormal material formed elsewhere and brought to it, or is derived from 

 the blood. 



Amyloid degeneration occurs most frequently and abundantly in 

 the liver, spleen, kidneys, intestinal canal, and lymph nodes ; but it may 

 occur, usually in a less marked degree, in other parts of the body : in 

 the larger blood-vessels, in the interstitial tissue of the heart and mucous 

 membranes of the air passages, and in the generative organs. It may 

 occur locally or appear in various parts of the body at once. It most 

 frequently occurs in connection with severe wasting diseases, particu- 

 larly in those involving chronic suppuration and ulceratiou, especially of 

 the bones. It is common in tuberculosis, syphilis, in the cachectic con- 

 dition induced by malignant tumors, and is occasionally seen in severe 

 malarial infection, dysentery, and leukaemia. 1 



TECHNIQUE. For microscopical examination the tissue, either fresh or after pres- 

 ervation, should be cut into thin sections, and these deeply stained with one-per-cent 

 aqueous solution of methyl violet ; the sections are washed in water and mounted in 

 glycerin. The differentiation between the amyloid and other parts is more distinct if, 

 after staining, the specimen be dipped for an instant in HC1 and alcohol 1 : 100, and then 

 carefully rinsed, before mounting in glycerin. The degenerated areas are thus stained 

 rose-red (Fig. 18), while the normal tissue elements have a bluish-violet color. In some 

 cases, for reasons which we do not know, the amyloid substance does not show a well- 

 marked reaction with methyl violet. For the de- 

 tection of amyloid in fresh tissues by the iodine 

 reaction see p.' 28. 



Corpora Amylacea are small, spheroidal, 

 homogeneous or lamellated bodies (Fig. 

 19), which assume a bluish color on treat- 

 ment with solution of iodine or iodine and 

 sulphuric acid. They are frequently found 

 in the acini of the prostate gland, some- 

 times in large numbers; in the ependyma Fltt . 19 ._ COKPORA AMYI , ACEA . 

 of the brain and cord ; also in extravasa- From prostate g i an d. 



tions of blood and in various other situa- 

 tions. They may occur under normal as well as pathological conditions, 

 and are apparently of little importance. They seem to have nothing to 

 do with amyloid degeneration, although they somewhat resemble its 

 products. Some of the tube casts of the kidney resemble in many 

 respects the corpora amylacea. 2 



1 An extended study of amyloid degeneration may be found in a monograph by 

 Wtchmann, Ziegler's Beitrage, Bd. 13, p. 487, 1893. 



A later bibliography with a summary of experiments on the production of amyloid 

 degeneration in animals will be found in an article by Marimoir, Virch. Arch., Bd. cliii., 

 p. 353, 1898. 



2 For a study of the relationship of corpora amylacea to amyloid substances, see 

 Ophiils, Jour. Exp. Med., vol. v., p. Ill, I 



