Cell Injury

Question 1

What are some clinical findings in hypoxia?

Answer 1

Cyanosis
Confusion
Cognitive impairment
lethargy

Question 2

What are the consequences of ischemia?

Answer 2

Atrophy
Infarction of tissue
Organ dysfunction

Question 3

What is the hallmark of reversible injury to cells?

Answer 3

Cell swelling

Question 4

What is the hallmark of irreversible cell injury?

Answer 4

membrane damage

Question 5

What is cytochrome C and when/where is it released?

Answer 5

activates apoptosis–released when there is damage to the mitochondrial membrane–leaking into cytosol

Question 6

What is a fenton reaction and what does this cause?

Answer 6

Generation of OH free radical from H2O2—causing cell injury

Question 7

What does glutathione peroxidase do?

Answer 7

neutralizes H2O2, OH and NAPQ1–toxic intermediate of Acetaminophen

Question 8

What antioxidant neutralizes oxidized LDL?

Answer 8

Vit E

Question 9

What antioxidant neutralizes FRs from pollutants and cigarette smoke?

Answer 9

Vit C

Question 10

What enzyme converts superoxide to H2O2?

Answer 10

superoxide dismutase

Question 11

How is liver necrosis caused from acetaminophen poisoning?

Answer 11

CYP2E1 (MEOS)–converts high doses of acetaminophen into toxic intermediate NAPQ1–FR

Question 12

What is Chediak-Higashi syndrome (CHS)?

Answer 12

Defect in lysosomal transport protein affecting the synthesis and/or maintenance of storage of secretory granules

Result– giant lysosomal granules–defect in formation of phagolysoscomes–increased susceptibility to developing Staphylococcus aureus infection

Question 13

What is ferritin? What does serum levels of ferritin correlate with?

Answer 13

soluble iron-binding protein that stores iron in macrophages

Serum levels directly correlate with bone marrow into stores–decreased serum ferritin=iron deficiency

Question 14

What is hemosiderin?

Answer 14

insoluble product of ferritin degradation in lysosomes—does NOT circulate in serum

Question 15

What is Dystrophic calcification?

Answer 15

Deposition of Calcium phosphate in necrotic tissue–Ca enters tissue and binds to phosphate that has been released from damaged membranes—Ca and PO4 levels are normal

Question 16

What is metastatic calcification?

Answer 16

Deposition of calcium phosphate in the interstitial of NORMAL tissue due to increased serum Ca and PO4

Ca–hyperparathyroid/malignancy induced hypercalcemia
PO4- Renal failure/hypoparathyroid

Question 17

What type of growth alteration does the uterus undergo during pregnancy and how is this induced?

Answer 17

Estrogen induced hypertrophy and hyperplasia

Question 18

What growth alteration occurs in cardiac and skeletal muscle?

Answer 18

both can ONLY undergo hypertrophy

Question 19

What are some examples of pathogenic hypertrophy?

Answer 19

LV hypertrophy

cytomegalovirus infection–cytomegaly

Question 20

What are examples of increased hormone stimulation hyperplasia?

Answer 20

Endometrial gland hyperplasia–caused by increase in estrogen (decrease in progesterone inhibition)–increased risk of cancer

Benign prostatic hyperplasia (BPH)–caused by increased sensitivity to dihydrotestosterone(DHT)–NO increased risk of cancer

Question 21

What are some examples of chronic irritation hyperplasia?

Answer 21

Scratching of itchy skin—thickening of epidermis

Branchial mucous gland hyperplasia

Regenerative nodules in cirrhosis of liver–excess ETOH

Question 22

What are examples of Chemical imbalance hyperplasia?

Answer 22

Hypocalcemia–stimulates parathyroid gland hyperplasia

Iodine deficiency– thyroid enlargement–both hypertrophy and hyperplasia cause goiter formation

Question 23

What is an example of stimulating antibodies causing hyperplasia?

Answer 23

Hyperthyroidism in Graves Dz–due to thyroid stimulating antibodies directed against thyroid hormone receptors

Thyroid gland increases to increase synthesize of thyroid hormones

Question 24

What is an example of viral infection causing hyperplasia?

Answer 24

HPV causing epidermal hyperplasia/common wart

Question 25

Example of metaplasia from squamous to glandular epithelium?

Answer 25

Barrett esophagus---Occurs when there is acid reflux from the stomach into the distal esophagus---increase in goblet and mucus secreting cells for protection Increased risk of developing adenocarcinoma

Question 26

Example of metaplasia from glandular to other type of glandular?

Answer 26

Occurs in the pylorus and antrum epithelium in the stomach--infection cause by helicobacter pylori---cytokines produce chronic gastritis---increased goblet and paneth cells normally present in intestinal epithelium Increased risk of developing a gastric cancer

Question 27

Examples of metaplasia from glandular to squamous epithelium?

Answer 27

occurs in the main stem bronchus epithelium--pseudostratified columnar--develops squamous metaplasia in response to cigarette smoke--increased risk of cancer Mucus-secreting endocervical cells encountering acid pH of vagina--squamous cell metaplasia

Question 28

Example of metaplasia from transitional to squamous epithelium?

Answer 28

Schistosoma haematobium infection---urinary bladder increased risk for developing squamous cancer of the urinary bladder

Question 29

Example of mesenchymal metaplasia involving connective tissue?

Answer 29

osseous metaplasia-- bone tissue develops in an area of muscle trauma

Question 30

What are some risk factors for dysplasia?

Answer 30

``` Hyperplasia--endometrial gland Metaplasia-Barrett esophagus HPV infection Chemicals--cigarette smoke--squamous metaplasia in main stem bronchus UV light--squamous dysplasia ```

Question 31

What are the microscopic features of dysplasia?

Answer 31

Increased mitotic activity increased nuclear size and chromatin disorderly proliferation of cells with loss of cell maturation as cells progress to the surface

Question 32

Define coagulative necrosis?

Answer 32

Cell shape and organ structure preserved Loss of nucleus

Question 33

What are the characteristics of coagulative necrosis?

Answer 33

Most likely involves an ischemic infarct to any organ---except brain Wedge shaped and pale area

Question 34

What is a pale ischemic type of infarct?

Answer 34

Coagulative necrosis | Increased density of tissue--heart/kidney/spleen--prevents RBCs from diffusing through necrotic tissue

Question 35

What is a hemorrhagic (red) type of infarct?

Answer 35

Coagulative necrosis | loose-textured tissue--lungs/small bowel/testicle---allows RBCs to differs through the necrotic tissue

Question 36

Where is infarction more likely?

Answer 36

Kidney and spleen due to presence of end arteries

Question 37

Where is infarction least likely?

Answer 37

Lungs--due to the dual blood supply from pulmonary and bronchial arteries

Question 38

Define liquefactive necrosis?

Answer 38

Necrotic degradation of tissue that softens and becomes liquified

Question 39

What are some examples of liquefactive necrosis

Answer 39

Brain infarction--microglial cells abscess--neutrophils Pancreatitis--pancreas itself

Question 40

What are examples of caseous necrosis?

Answer 40

Formation of Granulomas from - -mycobacterium tuberculosis - -fungi (histoplasma)

Question 41

What is caseous necrosis?

Answer 41

variant of coagulation necrosis--combination of coagulative and liquefactive Acellular, cheese-like material present on gross examination Characteristic of granulomatous inflammation due to TB or fungal infection

Question 42

What is a Noncaseating granuloma and what are some examples of where it is seen?

Answer 42

Lack excessive amour of lipid--so they don't exhibit caseation Ex: crohn dz/sarcoidosis/foreign body giant cell granulomas

Question 43

What is dry gangrene?

Answer 43

Coagulative necrosis that resembles mummified tissue--lower limbs and GI

Question 44

What is wet gangrene?

Answer 44

Gangrenous necrosis with infection--liquefactive necrosis

Question 45

What is enzymatic necrosis?

Answer 45

Necrosis to adipose tissue located around an acutely inflamed pancreas --Ca and fatty acids coming together---saponification

Question 46

What is traumatic fat necrosis?

Answer 46

Necrosis in fatty tissue--breast/abdomen as a result of blunt trauma or surgery --Ca and fatty acids coming together---saponification

Question 47

What is fibrinoid necrosis?

Answer 47

Necrotic damage to blood vessel wall---immune mediated dz Immune vasculitis/malignant HTN/rheumatic fever

Question 48

What proteins maintain mito membrane integrity and prevent leakage of mito proteins that can trigger apoptosis?

Answer 48

BCl-2 and BCl-XL

Question 49

What BCl-2 effectors activate the intrinsic pathway of apoptosis?

Answer 49

BAX and BAK

Question 50

What receptors and ligands are involved in the extrinsic pathway of apoptosis?

Answer 50

TNF receptors | FAS ligands---binds FAS death receptor (CD95) activating caspases

Question 51

What is pyropotosis?

Answer 51

pro inflammatory cell death using caspase-1 monocyte/macrophage/dendritic cell destruction----salmonella/shigella/legionella