L3 Questions Flashcards
How do growth factors contribute to regeneration and repair in normal cell proliferation and growth?
GFs are recruited to activate cells and bring them into the cell cycle, proliferation of stuff (VEGF, FGF, HGF, etc.)
How do signalling mechanisms for activation of transcription contribute to regeneration and repair in normal cell proliferation and growth?
signals activate complex (usually complex) pathways that affect the transcription factors in the nucleus, this usually leads to proliferation but can also lead to multiple functional effects
How do stem cells contribute to regeneration and repair in normal cell proliferation and growth?
stem cells can be activated and then differentiated into mature cells, they are important for the replenishing of cells, especially in cell populations with high cell turnover
What are the cellular subtypes regulating the multiple steps of skin regeneration?
inflammatory cells, epithelial cells, fibroblasts, endothelial cells
How do inflammatory cells contribute to healing (esp. skin regeneration)?
they flag inflammation and starts the processes in acute inflammation, bringing other inflammatory cells to the site of injury, they also attack the pathogens
How do epithelial cells contribute to healing (esp. skin regeneration)?
they proliferate to replace the injured cells in a skin injury
How do fibroblasts contribute to healing (esp. skin regeneration)?
granulation tissue, remodelling and collagen deposition
How do endothelial cells contribute to healing (esp. skin regeneration)?
neo-angiogenesis (also blood flow)
What does the regenerative capacity of a tissue depend on?
The regenerative capacity of a tissue depends on the proliferative potential of its constituent cells. In different situations, regeneration may occur by proliferation of surviving cells or repopulation from adult stem cells
What controls cell proliferation?
Cell proliferation is controlled by the cell cycle. Cells are stimulated into the cell cycle by growth factors and interactions of cells with the ECM
What are the main phases of healing by scar formation?
inflammation, proliferation (granulation tissue (GT), re-epithelialisation, angiogenesis), and maturation (ECM, remodelling, scar)
What is repair by regeneration (e.g. liver) triggered by?
by cytokines and growth factors produced in response to tissue loss
What are some factors associated with delayed wound closure?
metabolic disease, circulatory diseases and age
What are some complications of wound healing?
fibrosis and ulcers
