Cell Injury Flashcards
What is hyperplasia?
Increase in the number of cells
What is hypertrophy?
Increase in the size of cells
What is atrophy?
Decrease in the size of cells
What is metaplasia?
Substitution of a different adult cell type
What is the first change with cell injury?
Cell function
What is hypoxic cell injury?
Ischemia causes decreased mitochondrial output due to lack of O2 which leads to decreased ATP which lead to decreased Na/K Pump activity.
This leads to increased intracellular Ca2+, Na+ and H2O which causes cellular swelling.
What is free radical injury?
Caused by free radicals such as ROS which come from cellular respiration can damage cells.
What can reperfusion cause?
Reperfusion injury which is caused by free radical injury with the return of blood/O2 to ischemic tissue that leads to the production of free radicals
What are some features of reversible cell injury?
- Cellular swelling
- Steatosis (fatty change)
- Myelin figures
- ER swelling
- Membrane blebs
What are the features of irreversible cell injury?
Cell death via necrosis or apoptosis
What is the main difference between necrosis and apoptosis?
Necrosis is characterized by an inflammatory response which will recruit neutrophils.
What is coagulation necrosis?
Associated with severe ischemia and is seen in the heart and kidney
What is liquefactive necrosis?
Associated with bacterial infections and brain infarct/hypoxia.
Bacteria release enzymes causinga rapid loss of cellular structure and a collection of liquid, amorphous debris
What is caseous necrosis?
Associated with inflammatory granulomas and the necrotic tissue is soft, white and friable.
What is enzymatic fat necrosis?
Cell death in the pancreas leads to the release of lipases that digest lipids that mix with Ca into yellow soaps
What is gangrene?
It represents coagulation (ischemic) necrosis, usually of an extremity, bowel or gallbladder
Ischemic injury to the central nervous system from right internal carotid arterial occlusion suffered by a 72 year old man will result in what pattern of necrosis?
Liquefactive
Which are the major mechanisms which result in membrane damage typical for a reperfusion injury following myocardial ischemia in a 68 year old woman?
Reactive O2 Species
Scattered acidophilic bodies are found in the liver of a 57 year old man who has recently developed nausea, vomiting, and scleral icterus. His serologic test for viral hepatitis A is positive. What is the most likely pattern of tissue alteration?
Apoptosis
An endocervical biopsy in a 23 year old woman demonstrates the presence of squamous epithelium. What process has occurred? Why?
Metaplasia
What is karyolysis?
The basophilia of the chromatin may fade, a change that reflects loss of DNA because of enzymatic degradation by endonucleases.
What is pyknosis?
Characterized by nuclear shrinkage and increased basophilia. The chromatin condenses into a solid, shrunken basophilic mass (also seen in apoptosis)
What is karyorrhexis?
The pyknotic nucleus undergoes fragmentation. In a day or two, the nucleus in the necrotic cell totally disappears.
What is a type of hyperplasia that is unrelated to cancer?
Benign Prostatic Hyperplasia
