Review Questions Flashcards
Which cells do not divide regularly, but can be stimulated to divide (can enter cell cycle if needed) and are located in parenchymal (solid) organs such as the liver and kidneys.
Quiescent Cells/Stable Cells
What are the 4 most important cells involved in wound healing?
- Leukocytes
- Macrophages
- Connective Tissue Cells
- Epithelial cells
(PMN’s play a brief scavenging role, then macrophages stay)
Which 3 cells participate in wound healing?
- Myofibroblasts
- Angioblasts
- Fibroblasts
Which cell in wound healing?
- Hybrid properties of both smooth muscle cells and Fibroblasts
- They contract within first few days of healing (reducing defect)
- Holds margins of tissue in close approximation
Myofibrobasts
Which cell in wound healing?
- Precursors of blood vessels that proliferate like sprouts from several small blood vessels at margins of wound
- Appear 2 - 3 days after incision
- By 5th - 6th day newy formed blood vessels are all over the field (allows for influx of blood w/ O2 and nutrients)
Angioblasts
Which cell in wound healing?
- Produce most of the extracellular matrix:
- Fibronectin- tensile strength to connective tissue matrix and glues other substances and cells together
- Collagen- wound initially w/ type 3 collagen (immature/young) laid by fibroblasts
Fibroblasts
- Necrotic tissue attracts Calcium Salts and frequently undergoes calcification
- Macroscopic deposition of calcium in injured/dead tissues
- Visible to naked eye
- Gritty/sand-like grains to firm, rock hard material
Dystrophic Calcification
- Calcifications in atherosclerotic coronary arteries (contributes to narrowing of vessels)
- Calcifications of mitral or aortic valves (leads to impeded blood flow/stenosis)
- **Calcifications seen around breast cancers, visualized on mammography**
- Infant periventricular calcifications seen in congenital Toxoplasmosis
Examples of Dystrophic Calcifications
- Deranged Calcium Metabolism (NOT CELL INJURY)
- Associated w/ increased serum calcium levels (leads to deposition of calcium in other locations)
Metastatic Calcifications
- Hyperparathyroidism
- Vitamin D toxicity
- Chronic Renal Failure
- Formation of Calcium stones in gallbladder, kidney, and bladder are due to precipitation of salts from solution into tissues
Examples of Metastatic Calcifications
- Dead tissue is due to what?
- Infarction
Hypoxic tissue is due to what?
Ischemia
What predisposes a patient to events of thrombosis and emboli?
Atherosclerosis
Result in localized ischemia and subsequent cerebral infarction
Both thrombosis and embolic events
Cerebral infarcts are designated as which 2 things?
- Hemorrhagic
- Bland/White
Cerebral infarcts caused by what are sites of hemorrhage?
Embolization
Cerebral infarcts caused by what are largely ischemic and therefore bland/white/anemic?
Thrombotic occlusion