Pathoma: Growth Adaptations, Cell Injury and Cell Death Flashcards
By what mechanism does cellular hypertrophy occur?
Gene activation, protein synthesis and increased production of organelles
By what mechanism does hyperplasia occur?
Stem cell activation
Tissues that cannot undergo hyperplasia
Cardiac, nervous and skeletal muscle
Pathologic hyperplasia that does not increase risk of cancer?
BPH
3 mechanisms by which organ atrophy occurs?
Apoptosis, ubiquitin-proteosome degradation of cytoskeletal intermediate filaments and autophagy via vaculole-lysosomal degredation.
Mechanism by which the columnar cells in Barrett’s esophagus underwent metaplasia?
Stem cell reprogramming
Type of metaplasia that carries no increased risk for cancer?
Apocrine metaplasia of the breast
How does vitamin A deficiency cause keratomalacia?
Vitamin A is necessary for production of the thin squamous lining of conjunctiva. When it is absent, those cells undergo metaplasia to stratified keratinized squamous epithelium.
What is dysplasia?
Disordered cellular growth
When is dysplasia irreversible?
When cellular stress persists and it transitions to a carcinoma.
What is hypoxia?
Low oxygen delivery to tissue
Common causes of hypoxia
Ischemia (decreased arterial perfusion, decreased venous drainage or shock), hypoxemia (PaO2
Common causes of hypoxemia
High altitude, hypoventilation, diffusion defect and V/Q mismatch
First sign of CO poisoning?
Headache
PaO2 and SaO2 in CO poisoning and methemoglobinemia?
PaO2 is normal. SaO2 is decreased.