Exam 1: Cellular Alterations Flashcards
what’s an idiopathic disease?
disease or condition without a definable cause
what’s an iatrogenic disease?
disease caused by physician or medical treatment
Why are injuries due to biologic agents different from other types of cellular injuries
b/c biologic agents are able to replicate and can continue to produce their injurious effects
What are the mechanisms of cellular injury?
- free radical formation (ROS
- hypoxia and ATP depletion
- disruption of intracellular calcium homeostasis
what’s hypoxia?
lack of oxygen to cells
what are the effects of hypoxic cell injury?
- cell reverts to anaerobic metabolism
- lactic acid production
- decreased ATP production
- inhibition of NA-K pump
- cell swells, cellular edema
how does impaired calcium homeostasis negatively affect the cell?
it may inappropriately activate a number of enzymes that are damaging to cells
What is Ionizing vs nonionizing radiation
ionizing- gamma rays, x-rays (energy above the visible UV light range)
nonionizing-infrared, microwaves,ultrasound (energy below that of visible light)
what are the 5 main cellular responses to injury?
atrophy, hypertrophy, hyperplasia, metaplasia, dysplasia
what is atrophy?
decrease in cell size due to decreased work load ex: -disuse -paralysis -lack of endocrine stimulation -decreased nutrition -ischemia
what is hypertrophy?
increase in cell size and increase in functional capacity
what is hyperplasia?
an increase in the number of cells in organ or tissue, only occurs in cells with mitotic division
what is metaplasia?
conversion of one adult cell type to another adult cell type, usually in response to chronic irritation and inflammation
what is dysplasia?
deranged cell growth of tissue that results in cells of various size, shape, and organization.
which cellular response to injury type is the most likely to become malignant?
dysplasia
what are some examples of reversible cell injury?
- pH changes
- increased glycolysis
- decreased protein synthesis
- failure of sodium potassium pump
what are some examples of irreversible cell injury?
- severe depletion of ATP
- nuclear changes
- membrane damage
- necrosis
what is necrosis?
death of a cell, tissue, or organ
what are four types of tissue necrosis? (licking cows feels cruel)
liquefaction, coagulation, fat, casseous
what’s liquefaction necrosis?
cells die, but enzymatic functions are not destroyed
what’s coagulation necrosis?
the development of acidosis, which denatures proteins of the cells
what’s fat necrosis?
death of adipose tissue from trauma or pancreatitis, destructive enzymes get released
what’s casseous necrosis?
TB lesions- looks like cottage cheese on xrays, dead cells persist
what is a gangrene?
a large area of necrotic tissue
what are the types of gangrene?
wet,dry, and gas
what are the characteristics of dry gangrene?
form of coagulation necrosis, occurs in extremeties(decreased arterial flow), skin wrinkles, turns black.
-has line of demarcation, between healthy and dead tissue
what are the characteristics of wet gangrene?
form of liquefaction necrosis due to interference of venous blood return
-area is cold,swollen,black,foul odor, blebs form
what are the characteristics of gas gangrene?
due to infection of necrotic tissue, by clostridium family. gas bubbles form in muscles
What is apoptosis? Is it a physiologic process or pathophysiology
apoptosis is shrinkage of the cell and wrinkling of the cell membrane. it’s both physiologic ( cell death provides more space for new cell growth) and pathologic ( too much could cause Alzheimer’s and Parkinson’s
What are the phases of wound healing and what occurs in each step
- inflammatory phase- time of injury. blood clotting(hemostasis), cleans debris
- proliferative phase- 2-3 days after injury, fibroblasts make collagen. granulation tissue form
- remodeling (maturation) phase- 3 weeks after injury. collagen synthesis.
What is healing by primary intention? Secondary intention—which is preferred and why
primary intention-wound healing with close approximation of edges(more preferred b/c minimal tissue loss
secondary intention- larger wound, more tissue loss and edges not clean
What factors will influence the process of wound healing
nutrition, blood flow, infection, age
what’s wound dehiscence?who’s at risk for it?
• Separation of the wound edges after suturing, abdominal wounds at risk
