166 vi;ti:ri.\.\kv patiiouicy. 



tissue is still a disputed point. It is certain that fixed and wan- 

 dering; ccmnective tissue cells are capable of this function. 

 Endothelial cells are a type of fixed connective tissue cells which 

 are active in regeneration of connective tissue. Alononuclear 

 leucocytes as well as lymphocytes may be capable of producing 

 connective tissue. The regenerating connective tissue cells 

 (fibroblasts) are either oval or spindle shaped, the latter pre- 

 dominating, especially during the active regeneration period. 



Endothelial cells are active in the production of new vessels. 

 Inflammatory tissue is usually more vascular than normal tissue. 

 In the vascularization of an inflammatory area the endothelial 

 cells produce long protoplasmic projections. Several of these 

 projections of different adjacent cells may fuse, thus forming an 

 anastomotic channel, or a single projection may separate in a 

 longitudinal direction, thus producing an extension of the old 

 channel. As the protoplasmic projections become larger and 

 longer there is an activity in the cell nucleus indicative of 

 mitosis, and cell di\ision soon follows. This process of proto- 

 plasmic projections and mitosis continues as long as the in- 

 flammatorv process is active. The irregular blood channels 

 (capillaries) so formed become surrounded by a layer of invol- 

 untarv muscle tissues and yellow elastic tissue as a result of 

 extension of muscle fibres and connective tissue cells from the 

 adjacent vessel, the whole structure being surrounded by a 

 loosely arranged layer of white fibrous connective tissue. Thus 

 the capillary becomes an arteriole. These cells that are active 

 in vascularization are designated angioblasts. They are the 

 progeny of endothelium. 



Inflammatory injuries to surface epithelium, as epidermis or 

 mucous membrane, are usually repaired l)y multiplication of the 

 cells bordering the injury. 



Irregular masses of nucleated protoplasm have been observed 

 in myositis and mav represent regenerating muscle cells. 



Kinds or Types or Inflammation. — It is difficult to classify 

 inflammation because of the numerous variable factors that com- 

 pose it. The following classification is based upon etiology, 

 exudate, tissue in^•olyed, and time or sevei■it^' of attack. 



Efiolaax. — Etiologically, inflammation mav be classified as 

 simple and infective. 



1. Simple inflammation is noninfective and results from me- 

 chanic, thermic, electric or chemic interference. 



Fractures, sprains, liruises and surgical-procedure wounds 

 are types of mechanic inflammation. 



As types of thermic inflammation, burns and frozen tissues 



