Week 10 P1 Flashcards
What are the four stages of wound healing?
Hemostasis, Inflammation, Proliferation, Remodeling
What cells are involved in Hemostasis?
Platelets
What cells are involved in the inflammatory phase?
Neutrophils, Macrophages, Lymphocytes
What cells are involved in the proliferative phase?
Fibroblasts, Endothelial cells, epithelial cells
What cells are involved in the remodeling phase?
Fibroblasts
What is the purpose of inflammation?
Inflammation is the body’s protective response to injury, infection, or harmful stimuli, aimed at eliminating the cause, removing damaged cells, and initiating tissue repair. It serves as a defense mechanism to promote healing.
The degree of long-term encapsulation (>= __________
weeks) depends on several factors:
1. Degree of ___________ during implantation
2. Amount of subsequent cell ____________
3. Location of implant size
4. __________________ time of implant
4 Weeks
degree of trauma
cell damage
retention time
What is the foreign body response?
Typical biological response to foreign ”body” Involves the formation of granuloma/granulation
tissue
Explain what a Foreign Body Giant Cells stain looks like.
Hematoxylin (+): Positively stained nuclei appear purple or dark blue. These are the multiple nuclei characteristic of giant cells formed by macrophage fusion.
Eosin (-): Negatively stained cytoplasm appears pink, indicating the protein-rich and cellular structure of the cytoplasm.
What are the possible scenarios for the
resolution of FBR?
Extrusion, Resorption, Integration Encapsulation
What is Extrusion?
The foreign material is pushed out of the body through the skin or mucosa
What is Resorption?
The foreign material degrades and is absorbed by the surrounding tissue
What is integration?
The material integrates with the surrounding tissue without provoking ongoing inflammation
What is encapsulation?
The foreign material is surrounded by a fibrous capsule, isolating it from the surrounding tissue
What is the purpose of in vitro assays?
evaluate the cytocompatibility (cell compatibility) of biomaterials to assess their safety and potential biological effects
Explain the process of direct contact in In vitro assays.
The biomaterial is placed directly onto a layer of cultured cells. This tests for immediate toxicity from physical interaction or surface chemistry.
Potential outcomes:
Cell death (cytotoxicity) near the material.
Altered cell morphology.
No significant effect, indicating good biocompatibility.
Explain the process of indirect contact in In vitro assays.
Cells are exposed to biomaterials through a medium or barrier (e.g., agar overlay or inserts), avoiding direct physical contact. This evaluates soluble factors, like released ions or small molecules, from the material.
Potential outcomes:
Inhibited cell proliferation or viability due to toxic leachates.
No changes in viability, indicating no toxic leachates.
Explain the process of leachables/degradation products in In vitro assays.
Cells are exposed to substances released from the biomaterial (e.g., degradation byproducts, unreacted monomers). This simulates the biomaterial’s effect over time.
Potential outcomes:
Accumulation of toxic byproducts affecting cellular function or causing inflammation.
Stable or minimal effects, indicating safe degradation.
