Chapter 1 Cell injury, death, and adaptations Flashcards
Define pathology
The study of suffering (disease)
The origin of disease (why)
Etiology
Steps in developing disease (how)
Pathogenesis
Various changes accompany disease
Morphologic
What are two examples of cellular stress?
Physiologic stress
Pathological stimuli
Why do cells and tissues adapt to stressors?
To attempt to preserve viability and function
List 4 main cellular adaptations
Hypertrophy
Hyperplasia
Atrophy
Metaplasia
When are cellular adaptations exceeded?
Reversible cell injury
Irreversible cell injury
Increased SIZE of cell and organ typically from mechanical stress and growth factors
Hypertrophy
In hypertrophy do cells divide?
Cells are incapable of division
What is a physiologic example of hypertrophy?
Weight lifters
What is a pathologic example of hypertrophy?
Ventricular hypertrophy from HTN
Increased NUMBER of cells
Hyperplasia
Hyperplasia is a response to what?
Growth factors
In hyperplasia do cells divide?
Cells must be able to replicate
What is a physiological example of hyperplasia?
Female breast, liver
What is a pathologic example of hyperplasia?
Papilloma virus - warts
Give an example when hyperplasia would accompany hypertrophy?
Pregnant uterus
Decreased SIZE of cells or organs
Atrophy
Describe proteins and atrophy
Decreased protein synthesis
Increased protein breakdown
Are cells dead in atrophy?
No, decreased function
List five causes of atrophy
Disuse Reduced blood supply Loss of innervation Loss of endocrine supply Aging (senile atrophy)
Thenar atrophy
Loss of innervation (atrophy)
REVERSIBLE change where one cell type is replaced by another
Metaplasia
Metaplasia is commonly a response to what?
Prolonged stressors
Give an example of metaplasia
Smoking and epithelial metaplasia
What are two common results of metaplasia?
Reduce the function of the cell
Increase chance of malignancy
List some causes of cellular injury
Trauma, genetic defects, hypoxia, poisons/toxins, nutritional imbalances, and aging
Describe reversible injury
Mild, LACK membrane damage and cell will return to normal once stressor is removed
What is the common appearance of a cell in reversible injury?
Cellular swelling and accumulation of fat in cytoplasm
Describe irreversible injury
Inability to correct mito dysfunction and membrane function
In cell death this is always pathological (inflammatory response)
Necrosis
This does not elicit an inflammatory response
Apoptosis
Nuclear dissolution without loss of membrane integrity
Apoptosis
List the morphological types of necrosis
Coagulative Liquefactive Gangrenous Caseous Fat Fibrinoid
A brown recluse spider bite is an example of what?
Necrosis
Characteristic of infarctions of solid organs except the brain
Coagulative necrosis
Describe the tissue in coagulative necrosis
Tissue structure is preserved for a few days
Denatures proteins and enzymes
Dead cells are completely digested and a liquid viscous mass results
Liquefactive necrosis
What is the most common cause of liquefactive necrosis?
Bacterial infections
CNS hypoxia
Liquefactive necrosis
Ischemia in the lower extremity
Gangrenous necrosis
Cheese like appearance that is friable yellow/white
Caseous necrosis
Give an example of caseous necrosis
Granuloma from TB
Medical emergency where leaked pancreatic enzymes cause fat saponification in the peritoneal cavity
Fat necrosis
What is the enzyme precursor in fat necrosis
Activated pancreatic zymogens
Typical of autoimmune reactions involving antigens and antibodies which are deposited in vascular walls
Fibrinoid necrosis
Describe the characteristic trait of fibrinoid necrosis
Bright pink stain
Give some examples of fibrinoid necrosis
Polyarteritis nodosa
Preeclampsia, lupus, organ transplant
Falling off
Apoptosis
Give a physiologic example of apoptosis
Gill slits in embryonic development
Give a pathologic example of apoptosis
HIV
What is hallmark of apoptosis
Activation of capsases
What are the two pathways of apoptosis?
Mitochondrial (intrinsic) pathway Death receptor (extrinsic) pathway
This pathway involves the tumor necrosis factor
Death receptor (extrinsic) pathway
Sel-eating
Autophagy
When does autophagy occur?
Survival during times of reduced nutrients
To rid misfolded proteins
Give examples of diseases where autophagy occurs
Alzheimers, Parkinson’s, ALS
This mechanism of cell injury is caused by hypoxia, nutritional deficiency, mitochondrial damage, and toxins
Depletion of ATP
This mechanism of cell injury is from ROS, irradiation, and hypoxia which causes a loss of membrane potential
Mitochondrial damage
This mechanism of cell injury is caused by ischemia and toxins
Influx of calcium
This mechanism of cell injury is caused by ischemia-reperfusion, irradiation, cellular aging, phagocytic activity, and inflammatory cells
Accumulation of ROS
This mechanism of cell injury is caused by ischemia, microbial toxins, various physical and chemical stressors, and characteristic of nearly all forms of necrosis
Defects in membrane permeability
This mechanism of cell injury is commonly caused by ROS or irradiation and will trigger apoptosis when too severe
DNA and protein damage
This type of injury impacts aerobic and anaerobic injury production
Ischemia and hypoxic injury
In an ischemic and hypoxic injury, reduced ATP leads to depletion of what?
Glycogen
In ischemia-reperfusion injury, the majority of injury results in the formation of what?
ROS
Ischemia-reperfusion injury is clinically important in what two cases?
Cerebral and myocardial infarction
Stroke and heart attack
Chemicals induce cellular injury via what two methods?
Direct action
Conversion
Conversion typically results from what system in the liver?
Cytochrome P-450
What is another term for intracellular accumulations
Inclusions
Intracellular accumulations are associated with what two things?
Cell injury and aging
Intracellular accumulations occur within what?
Cytoplasm, organelles, or nucleus
What are the four main pathways of intracellular accumulations?
Abnormal metabolism
Defective protein folding/transport
Defective or absent enzymes
Ingestion of indigestible materials
Give an example of abnormal metabolism
Fatty liver disease
Give an example of ingestion of indigestible materials
Black lung
What is another name for fatty changes
Steatosis
Fatty changes is an accumulation of what?
Triglycerides
What are the two most common causes of fatty changes?
Alcoholism and type II diabetes
Dead/injured cells from examples such as aortic valve stenosis and atherosclerosis
Dystrophic calcification
Deposition of calcium into normal tissues
Metastatic calcification
An example of metastatic calcification can be found in hypercalcemia due to an increase in what hormone?
Parathyroid hormone
Give two additional examples of metastatic calcification
Multiple myeloma and sarcoidosis
Decreased ability to perform cellular division
Replicative senescence
Give two examples of cellular aging
Werner syndrome
Progeria