Pathology 4: Cell injury 2

Question 1

What are mechanisms of cell injury?

Answer 1

ATP Depletion
Membrane damage
Metabolic disturbance
Genetic damage

Question 2

What does mitochondrial damage lead to?

Answer 2

• Leakage of proapoptotic proteins (point of no return)
• Decrease of ATP with multiple downstream effects

Question 3

Effects of Ca2+ entry from damage of ions pumps

Answer 3

• Increase of mitochondrial permeability
• Activation of multiple cellular enzymes

Question 4

Increased in ROS (Reactive oxygen species)

Answer 4

ROS: Metabolites lead to
Damage to lipids, proteins, DNA

Question 5

Damage to membrane

Answer 5

Plasma membrane damage:
- Loss of cellular components
Lysosomal membrane damage:
- Enzymatic digestion of cellular components

Question 6

Effects of protein misfolding and DNA damage

Answer 6

Activation of proapoptotic proteins

Question 7

9 causes of cell injury

Answer 7

• Oxygen deficiency
• Physical damage
• Infectious agents
• Nutrition imbalance
• Genetic damage
• workload imbalance
• Toxic damage
• Immune dysfunction
• Aging

Question 8

What is ischemia?

Answer 8

Impairment in blood supply to the tissue.
- Physical or mechanical barrier of bloody supply to tissue.
- No O2 or glucose delivered and no water removed.

Question 9

Infarction

Answer 9

Death of tissue related to ischemia

Question 10

Oxygen deficiency leads to

Answer 10

Hypoxia
Ischemia

Question 11

Types of physical damage

Answer 11

Trauma
temp extremes
radiation/electricity

Question 12

Workload imbalance can lead to

Answer 12

Hypertrophy
Hyperplasia
Atrophy

Question 13

What is hypoxia? Example?

Answer 13

Lack of oxygen (anemia)

Question 14

Causes of toxic damage

Answer 14

Chemicals: drugs, toxins

Question 15

Name of reversible cellular injury- morphologic features

Answer 15

Hydropic degeneration

Question 16

Hydropic degeneration

Answer 16

• Increased cell size/volume
  -Cytoplasmic vacuolation (swollen mitochondria, ER, and Golgi)

Question 17

What happens when reversible cell injury is becoming irreversible

Answer 17

Acute cell swelling can lead to death

Question 18

What is necrosis

Answer 18

Cell death of injury by hypoxia, ischemia, cell membrane damage

Question 19

Acute swelling effects

Answer 19

Swelling can lead to necrosis and point of no return is unclear.
- Restoring O2 supply can lead to free radical creation.

Question 20

Cell membrane damage due to

Answer 20

Chemical injury
Free radical injury

Question 21

Anti-oxidant protective mechanisms to avoid free radical injury

Answer 21

• Superoxide dismutase (SOD)
• Glutathione peroxidase
• Vitamins E,C

Question 22

What is Ischemia-reperfusion injury

Answer 22

• continued damge to tissue following restoration of blood supply to ischemic tissue
• Generation of ROS
• Ca2+ influx, impaired ion pumps

Question 23

Histologic changes for necrosis

Answer 23

• Cytoplasmic hypereosinophilia
• Nuclear changes: Pykonsis, Karyorrhexis, karyolysis

Question 24

What is pyknosis?

Answer 24

Nucleus: shrunken, dark, round

Question 25

What is karyorrhexis?

Answer 25

Nuclear fragments

Question 26

What is karyolysis?

Answer 26

Pale nucleus (dissolution of chromatin)

Question 27

Necrosis: morphologic types- gross appearance

Answer 27

• Coagulation necrosis
• Caseous necrosis
• Liquefactive necrosis
• Gangrenous necrosis
• Fat necrosis

Question 28

What is Coagulation necrosis?

Answer 28

The tissue is dead but the outline of the architecture remains in place

Question 29

What is Caseous necrosis?

Answer 29

Cheese-like fibrous decay. A lot of leukocytes/WBC fo inflammation response

Question 30

What is Liquefactive necrosis?

Answer 30

Often in brain, Softening of brain = Malacia

Question 31

What is Gangrenous necrosis?

Answer 31

• Occurs in the extremities or skin from loss of blood supply
  Wet: heavy, wet, full of blood and edema
  Dry: usually distal limbs becoming leather-like

Question 32

What is Fat necrosis?

Answer 32

Will Saponify- Chalky white development of fat.