284 Inflammation. 



material and indicates an unfavorable prognosis for the inflamma- 

 tion because of tlie almost unavoidable absorbtion of toxic matter 

 into the fluids of the body. 



All chronic inflammations, whatever the character of the exu- 

 date, result in the production of vascular connective tissue ; the 

 existence of a bacony, indurated, semitransparent or opaque milky 

 tissue in or about an inflammatory area is a distinct evidence of 

 its chronicity. This is said to be a productive iniiammution. What 

 factors are responsible for this tissue formation cannot be definitely 

 determined. It may be assumed that the same chemotactic in- 

 fluences, which are at the bottom of the escape of the leucocytes 

 from the vessels, stimulate the physiological formative energy of 

 the cells, in other words exert a demand for growth. The young 

 cells derived from these fixed cells are capable of some degree of 

 motility and indeed do move ; and the growing connective tissue cells 

 and endothelial cells are forced to take the direction in which 

 chemotactic and nutritive materials are located. The primary exu-' 

 date, especially fibrin, possesses this power of attraction, the fibro- 

 blasts beneath a fibrinous covering being found actively proliferat- 

 ing and pushing into the fibrin. It is possible that the infiltration 

 of a tissue with exudate directly occasions an excessive nutrition 

 of the cells, enabling them to form more protoplasm and then di- 

 vide ; and again the formation of spaces and the loss of substance 

 of the tissues should be considered, these factors favoring the de- 

 velopment of inflammation, and having a tendency to increase physi- 

 ological regeneration by release of tissue tension. The area of the 

 proliferation depends upon the extent and duration of the inflam- 

 mation. As already stated, the embryonic tissue appears in the form 

 of granulations upon free surfaces (wounds, ulcers, fistulous pas- 

 sages, serous membranes). With a reddish-gray or fleshy red color, 

 it presents a granular, uneven, undulating surface, from which in 

 aseptic inflammation is given ofif a serous, reddish, viscid exudate, 

 or when bacteria are present a purulent fluid. The granular appear- 

 ance which gives to the tissue its name (grainihiiii, a small grain) 

 is due to the projection of the outward growing capillaries which 

 extend out in loops and intertwine about the arteries like the top 

 branches of the trees in a leafy wood. The precise tint of the 

 granulation tissue, at times more deeply red or again more grayish 

 red, depends upon the relative engorgement of the capillaries or 

 the predominance of the gray color of the cells lying between the 

 vessels. These intercapillary cells are leucocytes and fibroblasts, 

 usually spindle shaped. On serous surfaces granulation tissue is apt 



