Cell Injury and Adaptation

Question 1

___ is an increase in cell numbers

Answer 1

hyperplasia

Question 2

___ is a decrease in cell numbers

Answer 2

hypoplasia

Question 3

___ is an increase in cell size, and thus, tissue size

Answer 3

hypertrophy

Question 4

___ is a decrease in cell size

Answer 4

atrophy

Question 5

cellular adaptations may lead to a change in cell type, called ___

Answer 5

metaplasia

Question 6

Hypertrophy is the result of increased production of cellular proteins–this is due to what 3 things?

Answer 6

1-hormones (mediated by growth factors and cytokines)
2-increased stress/workload
3-increased neurologic stimulus

Question 7

What are the two physiologic causes of hyperplasia?

Answer 7

1-hormonal

2-compensatory (after loss or injury)

Question 8

What are the two pathologic causes of hyperplasia?

Answer 8

1-excess hormone or growth factor

2-response to some viral infections

Question 9

The liver, and potentially the kidney, respond to ____ produced by mesenchymal cells throughout the body to promote regeneration

Answer 9

scatter factors

Question 10

What are the 6 causes of atrophy?

Answer 10

1-decreased workload
2-loss of innervation
3-diminished blood supply/ischemia
4-inadequate nutrition
5-loss of endocrine stimulation
6-pressure from external compression or duct obstruction, and sometimes from autoimmune destruction

Question 11

____ is a reversible change in which one adult cell type is replaced by another adult cell type; it is often adaptive, like due to chronic inflammation to protect the body, but it can lead to malignant transformation

Answer 11

metaplasia

Question 12

What are the 7 causes of cell injury?

Answer 12

1-oxygen deprivation (hypoxia, anoxia, ischemia)
2-physical agents (heat, trauma, radiation, electric shock)
3-chemical (drugs, environment, alcohol–either the chemical itself or a toxic metabolite)
4-infectious agents (viruses, bacteria, parasites, prions)
5-immunologic reactions from autoimmunity or anaphylaxis
6-genetic derangements like sickle cell or CF
7-nutritional imbalances

Question 13

____ is the most common cause of acute liver failure in the US

Answer 13

acetominophen toxicity

Question 14

Acetaminophen toxicity is treated with ____, which reduces the death rate, but it must be given within 10 hours

Answer 14

antidote N-acetylcysteine

Question 15

Acetaminophen is usually a safe drug but there are 4 problems that can occur:

Answer 15

1-too much acetaminophen, not enough glutathione to bind
2-increased activity of CYP system (more than normal 5% is pulled into CYP system so more hepatotoxic compounds are created)
3-there is a decreased amount of glutathione present to bind the hepatotoxic compounds
4-there is decreased conjugation to sulfate and glucuronide

Question 16

How does N-acetylcysteine treat Acetaminophen overdose?

Answer 16

it helps to increase hepatocyte glutathione levels

Question 17

A decreased amount of stored glutathione is usually due to what 2 things?

Answer 17

malnutrition and alcoholism

Question 18

Alcohol, anticonvulsants, and antituberculous drugs can increase acetaminophen toxicity–how?

Answer 18

these cause excessive activity of cytochrome P450 system

Question 19

The ____ correlates plasma levels of acetaminophen with time to assess acute toxicity; it can’t be used for chronic use or toxicity assessment

Answer 19

Rumach Matthew Nomogram

Question 20

What is often the initial finding of cell injury?

Answer 20

ATP depletion

Question 21

Which is worse for cells, ischemia or hypoxia? why?

Answer 21

ischemia–not only losing oxygen supply but also glucose and have accumulation of waste products

Question 22

What is the reflow phenomenon?

Answer 22

It is when a previously ischemic area has blood re-introduced to it

Question 23

What are the 6 effects of ATP depletion?

Answer 23

1-decreased function of energy dependent sodium pump–leads to cell swelling
2-change energy metabolism to glycolysis, increasing lactic acid levels and lowering cell pH
3-failure of calcium pump
4-reduction in protein synthesis
5-abnormal folding of proteins
6-membrane damage–mitochondrial, ER, lysosomal, cell…

Question 24

What are the repercussions of ATP depletion and calcium influx?

Answer 24

-membrane damage, nuclear damage, and further ATP depletion

Question 25

Production of free radicals is increased in the presence of what three metals?

Answer 25

iron, copper, and zinc

Question 26

What 4 things protect the cell from free radicals?

Answer 26

1-rapid spontaneous decay of the unstable compounds 2-antioxidants Vit E, A, C, and glutathione 3-iron and copper binding proteins 4-enzymes such as catalase, superoxide dismutase, and peroxidases

Question 27

How do free radicals damage cells? Three ways

Answer 27

1-damage the cell membrane through lipid peroxidation 2-oxidative modification of proteins, causing them to lose enzymatic activity and fold abnormally 3-reacts with DNA to produce single and double stranded breaks and mutations

Question 28

Glucose 6 phosphate dehydrogenase deficiency, which is a decreased ability of cells to protect themselves and presents clinically with "coke" colored urine is a disease caused by what?

Answer 28

free radicals

Question 29

When a cell has ____, it is an irreversible damage and cell death is inevitable

Answer 29

mitochondrial damage

Question 30

What are the two factors that make cell injury irreversible?

Answer 30

1-mitochondrial function can't recover | 2-profound disturbances in membrane function

Question 31

How can reperfusion cause worsening of injury?

Answer 31

- reoxygenation causes generation of ROS - increases intracellular calcium overload - inflammation - activation of complement system - can also cause hemorrhage

Question 32

In this type of cell death, the cell membrane ruptures, the lysosomal membrane ruptures, and the internal cell contents leak out, inflammation ensues

Answer 32

necrosis

Question 33

What causes the cell swelling in tissue necrosis?

Answer 33

ATP deprivation and failure of sodium/potassium pumps

Question 34

What causes the pH drop associated with tissue necrosis?

Answer 34

the cell changes to anaerobic conditions and lactic acid levels increase

Question 35

This type of necrosis is typically caused by ischemia and denaturation predominates, it is characteristic of hypoxic death of all cells except brain

Answer 35

coagulative necrosis

Question 36

This type of necrosis occurs commonly in the brain after infarct--autolysis predominates and the dead cells are completely digested

Answer 36

liquefactive necrosis

Question 37

This type of necrosis can be both coagulative and liquefactive and is usually seen in the lower leg; it can be wet or dry

Answer 37

gangrene

Question 38

This type of necrosis is often seen in Tb, it forms granulomas, and is called "cheesy"

Answer 38

caseous

Question 39

This type of necrosis is unique to fat and it may occur after trauma, surgery, or spilling of pancreatic enzymes; the fat becomes an irritant--often seen in pancreatitis, breast trauma

Answer 39

fat necrosis

Question 40

This type of necrosis occurs in blood vessels after immune reactions

Answer 40

fibrinoid necrosis

Question 41

Cell death by necrosis releases molecules that can be toxic--like potassium, uric acid, and myoglobin. How is potassium toxic?

Answer 41

the potassium can cause EKG changes, and arrhythmias can occur

Question 42

____ is programmed cell death in which own enzymes are activated for cell death

Answer 42

apoptosis

Question 43

Apoptosis is useful in prevention of what two things?

Answer 43

autoimmunity and too much inflammation

Question 44

What are the pathological conditions that induce apoptosis? 7

Answer 44

1-chromosomal DNA damage can't be fixed; loss of p53 gene 2-accumulation of misfolded proteins 3-cell death due to injurious stimuli 4-cell injury in certain viral diseases 5-pathologic atrophy after duct obstruction 6-cytotoxic T-cell apoptosis

Question 45

Which type of cell death (necrosis or apoptosis) is energy dependent?

Answer 45

apoptosis

Question 46

This type of cell death starts with a genetically programmed signal transduction, but it more resembles necrosis with cell swelling, loss of ATP, etc.; it as no caspases but it starts like extrinsic phase of apoptosis with TNF receptor activation

Answer 46

necroptosis

Question 47

____ occurs in cells infected by microbes--when the body can't get rid of the microbe it kills the cell to kill the microbe

Answer 47

pyroptosis

Question 48

_____ is the uptake of particulate material

Answer 48

phagocytosis

Question 49

____ is the uptake of soluble material

Answer 49

pinocytosis

Question 50

____ is the digestion of cell's own components

Answer 50

autophagy

Question 51

abnormal intracellular fat accumulation due to either normal amounts of lipids but decreased metabolism and removal or increased amount of lipids greater than cells ability to remove it

Answer 51

steatosis

Question 52

this type of intracellular accumulation is due to lipid peroxidation of polyunsaturated lipids in the cell, a sign of free radical injury

Answer 52

lipofuscin

Question 53

an alpha-1 anti-trypsin disease will result in what?

Answer 53

intracellular accumulation of proteins

Question 54

A gross excess of ____ intracellularly is associated with liver, heart, and pancreas damage

Answer 54

ferratin

Question 55

____ calcification is not dependent on increased serum levels of calcium or phosphate and it is seen in areas of necrosis or areas of previous tissue damage or necrotic tissue, like in heart valves or old scars

Answer 55

dystrophic

Question 56

___ calcification is due to high levels of calcium and phosphate, and occurs primarily in normal interstitial tissues of organs which have an alkaline environment like the stomach, lungs, kidneys, cornea, systemic arteries, and pulmonary veins

Answer 56

metastatic

Question 57

Chronic renal failure due to intracellular accumulations of calcification is often due to elevated phosphate resulting in what?

Answer 57

secondary hyperparathyroidism

Question 58

___ are short repeated sequences of DNA present at the ends of chromosomes that are important for ensuring the complete replication of chromosome ends and protecting chromosomes from fusion and degradation

Answer 58

telomeres

Question 59

___ maintains the length of telomeres, is required for replication, and is important in neoplasms

Answer 59

telomerase

Question 60

_____ is after a fixed number of divisions the cells become arrested in non-dividing state; it is determined by genetics; after arrest the cell no longer responds to normal growth signals

Answer 60

cellular senescence

Question 61

Telomerase plays a key role in cell aging, is normally present in only germ and stem cells but it is also present in what cells (bad!)?

Answer 61

cancer cells

Question 62

This syndrome begins at about 20yo, has growth retardation, muscle and connective tissue atrophy, skin aged appearance, and joint deformities, development of cataracts and death around age 40 due to atherosclerosis, diabetes, or cancer

Answer 62

Werner's syndrome

Question 63

Werner's syndrome is caused by a mutation in the ___ gene

Answer 63

DNA helicase

Question 64

This disease is rare and appear normal at birth except that bones of skull fail to fuse; by the end of the first year there is growth retardation, loss of all body hair, lack of proper calcification of bones, loss of subcutaneous fat, thinning of skill and distinctive facial features like receding chin, large head, eak like nose, and protruding eyes. Patients have normal mentality but never reach puberty and die from extensive atherosclerosis at 12-13yo; the cause is unknown

Answer 64

Hutchinson-Gilford Progeria