8.2 inflammation Flashcards
(40 cards)
Q: What is healing and repair?
A: The restoration of damaged living tissue, organs, and biological systems to normal function through regeneration and repair.
Q: What are the types of tissue growth?
A: Labile (continuously dividing), Stable (G0 cells that divide when needed), and Permanent (terminally differentiated cells).
Q: What are examples of labile cells?
A: Columnar epithelium in the GI tract and hematopoietic cells in bone marrow.
Q: What are examples of stable cells?
A: Parenchymal cells in the liver and kidney, fibroblasts, and epithelial cells.
Q: What are examples of permanent cells?
A: Cardiac myocytes in the heart.
Q: What factors influence the repair process?
A: Extent of damage, location, duration of the injuring agent, infection, poor perfusion, nutritional status, steroids, mechanical stress, and foreign bodies.
Q: What are the possible outcomes of tissue injury?
A: Regeneration, healing with scar formation, and fibrosis.
Q: What is regeneration?
A: Growth of cells and tissues to replace lost structures.
Q: What does regeneration require?
A: Intact tissue scaffolds and appropriate stem cells.
Q: What is healing in tissue repair?
A: Formation of scar tissue using ECM and collagen.
Q: What is fibrosis?
A: Excessive fibrous tissue formation that can impair function.
Q: What is an example of fibrosis impacting function?
A: Fibrosis following muscle injury compromises contractile function.
Q: Can humans regenerate like some animals?
A: No, humans exhibit compensatory growth rather than true regeneration.
Q: What is an example of compensatory growth in humans?
A: Liver after partial hepatectomy—25% can regenerate functionally, but not structurally.
Q: What are hyperplasia and hypertrophy?
A: Hyperplasia is an increase in cell number; hypertrophy is an increase in cell size.
Q: What occurs in the kidney after unilateral nephrectomy?
A: The remaining kidney undergoes compensatory hypertrophy and hyperplasia to match the mass of two kidneys.
Q: Is lung regeneration possible?
A: Some studies suggest alveoli may regenerate, but evidence is limited.
Q: What regulates tissue healing and repair?
A: Biochemical factors from injury, cell death, or trauma that induce resting cells to enter the cell cycle.
Q: How is cell cycle activity controlled during repair?
A: By balancing stimulatory/inhibitory factors, shortening the cell cycle, and reducing cell loss.
Q: What are the types of cell responses to growth signals?
A: Autocrine (self-signaling), Paracrine (nearby cells), Endocrine (distant cells).
Q: What growth factors are involved in repair?
- EGF: Platelets, keratinocytes, fibroblasts
- VEGF A-D: Mesenchymal, endothelial cells
- PDGF A-D: Platelets, macrophages; chemotactic and promotes angiogenesis
- TGF-β: Keratinocytes, macrophages; chemotactic, stimulates fibroblasts, angiogenesis, and collagen production
Q: What is the extracellular matrix (ECM)?
A: Non-cellular components of tissues/organs that provide structure and support.
Q: What are the types of ECM?
A: Interstitial matrix and basement membrane.
Q: What are components of ECM?
A: Collagen (fibrillar and non-fibrillar), elastin, fibronectin, proteoglycans, hyaluronate, laminin, glycoproteins.
