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Degeneration

cells, generation, processes and abnormal

DEGENERATION. In medical pathology degeneration is one of the processes that occur in the cells of an organ whereby different grades of disintegration and shrinking take place. It is one of the retrograde or breaking down processes in contrast to those of abnormal growth and increase, although in many of the degenerations both processes are going on side by side. When abnormal intracellular metabol ism slowly converts the cell plasma into useless and abnormal substances the process is known as degeneration, and then following upon such degenerations there usually results a partial or complete death of the plasma, leading to the destruction of the cell. In large measure, ac cording to the character of the substances pro duced in the degenerative processes, various forms of degeneration are known. If in the organs there is a deposit of a waxy or lardy substance derived from the serum of the blood, the degeneration is known as amyloid degenera tion. This is very frequently found in several organs at the same time, and results in large part from the infectious diseases accompanied by nutritional disturbances. Thus, in connec tion with chronic tuberculosis and syphilis amy loid degeneration is apt to occur. Hyaline de generation is another form, which takes place in the connective tissue by which that type of cell is rendered homogeneous. Hyaline de generation commonly occurs in the arteries and heart-valves, and is frequently associated with chalky infiltrations in these structures. Colloid

degeneration occurs in certain forms of cancer in which the substance in the cells resembles softened glue. Mucoid degeneration consists in the transformation of the leading tissues into a transparent, viscid, homogeneous mass consist ing of mums and pseudo-mucins. Mucoid de generation takes place largely in the connective tissue in the epithelial cells, and sometimes as a result of the disturbance of the functions of the thyroid gland as in myxadema. Fatty de generation is a degeneration in which fat globules are deposited in the cells. Albuminous degeneration, or cloudy swelling, as it is some times called, consists in a fine granulation of a number of cells in the body, particularly in the kidneys, liver and brain. This acute degenera tion is very frequently associated with fatty degeneration, and is due in great part to anoma lies of nutrition largely produced by bacterio logical agencies, as in the infectious diseases, and also at times to auto-intoxic products having their origin within the body itself as a result of perverted oxidation. Pigmentary de generation is another form, in which are depos ited in the cells small or large quantities of iron compounds derived largely from the blood and known as pigments. The abnormal deposition of lime in living tissue is known as calcareous degeneration. It occurs in the walls of the arteries in arteriosclerosis.