Medical brain notes 15

  REGENERATION AND HEALING   Regeneration and healing of damaged cells and tissues starts almost as soon as the inflammatory process begins. Tissue repair involves 5 overlapping processes: ·              Hemostasis (coagulation, platelets)   ·              Inflammation (neutrophils, macrophages, lymphocytes, mast cells)   ·              Regeneration (stem cells and differentiated cells)   ·              Fibrosis (macrophages, granulation tissue [fibroblasts, angiogenesis], type III collagen)   ·              Remodeling (macrophages, fibroblasts, converting collagen III to I)   The extracellular matrix (ECM) is an important tissue scaffold with 2 forms, the i...

  ABERRATIONS IN WOUND HEALING   ·              Delayed wound healing  may be seen in wounds complicated by foreign bod-ies, infection, ischemia, diabetes, malnutrition, scurvy, etc.   ·              Hypertrophic scar  results in a prominent scar that is localized to the wound,due to excess production of granulation tissue and collagen. It is common in burn patients.   ·                Keloid formation  is a genetic predisposition that is common in African Amer-icans. It tends to affect the earlobes, face, neck, sternum, and forearms, and it may produce large tumor-like scars extending beyond the injury site. There is excess production of collagen that is predominantly type III.