Glossary of Pathology - Cell Repair

Start Studying! Add Cards ↓

What are the phases of the cell cycle?
G1 (presythetic), S (DNA synthesis), G2 (premitotic), M (mitotic), G0 (resting phase)
What are the 3 different types of regenerative capacities of cells?
continuously dividing (labile) cells
quiescent (stable) cells
non-dividing (permanent) cells
What are some examples of labile cells?
stratified sqaumous epithelia of skin, oral cavity, vagina, cervix; cuboidal epithelia of exocrine ducts; columnar epithelium of GI tract, uterus, fallopian tubes; transitional epithelium of urinary tract; hematopoietic cells
What are some examples of quiescent cells?
(can regenerate; driven from G0 to G1 after cell loss)
parenchymal cells of liver, kidney, pancreas, vascular endothelial cells, smooth muscle
What are some examples of non-dividing cells?
nerve cells and cardiac myocytes
What does epidermal growth factor (EGF) do?
promotes growth of endothelial cells, fibroblasts, and epithelial cells; is a progression factor
What other growth factor is homologous to EGF?
TGF-alpha (transforming growth factor)
What types of cells synthesize/secrete platelet-derived growth factor (PDGF)?
activated platelets and macrophages, endothelial and smooth muscle cells, tumors
What are the functions of PDGF?
promotes chemotactic migration and proliferation of monocytes, fibroblasts, and smooth muscle cells
Is PDGF a competence factor or a progression factor?
competence factor: promotes proliferative response of fibroblasts and smooth muscle cells upon concurrent stimulation by progression factors
What is the function of basic fibroblast growth factor (b-FGF)?
promotes synthesis of extracellular matrix protein (including FIBRONECTIN) by fibroblasts, endothelial cells, monocytes, and other cells (eg can induce all steps necessary for angiogenesis)
What is the function of fibronectin, and what factor stimulates its synthesis?
-is chemotactic for fibroblasts, monocytes, endothelial cells
-promotes angiogenesis
-links extracellular matrix components and macromolecules to cell-surface integrins
-stimulated by b-FGF
What are the functions of transforming growth factor beta (TGF-beta)?
-chemotactic for monocytes and fibroblasts
-is a growth inhibitor (at high conc) for many cell types
-may aid in repair process
What are the macrophage derived growth factors, and what are their functions?
TNF and IL-1 (e.g. cytokines); promote chemotaxis and proliferation of fibroblasts
What is granulation tissue?
following acute inflammatory response, nonregenerated parenchymal cells are replaced by proliferating fibroblasts and vascular endothelium; pink, soft tissue beneath scab
What is the progression from granulation tissue to scar tissue?
granulation tissue accumulates collagen (connective tissue matrix) produced by fibroblasts; tissue becomes less cellular and less vascular
What is an example of a wound healing by first intention?
healing of a surgical incision closed with sutures
What is a key characteristic of wound healing by second intention?
wound contraction; w/in 6 weeks large skin defects shrink to 5-10% of original size; e.g. infarction, abscess, ulceration, large wounds
What are some factors that delay or impede repair?
infection, impaired circulation, retention of debris, dietary deficiency of ascorbic acid or protein (required for collagen formation)

*metabolic d/o's, e.g. diabetes (assoc w/poor circulation and susceptibility to infection)

Add Cards

You must Login or Register to add cards