Cellular Injury Flashcards Preview

Term 3: Immunology/Pathology > Cellular Injury > Flashcards

Flashcards in Cellular Injury Deck (41):
1

What is a cellular adaptation?

-a reversible functional and structural response to a stress or stimulus

2

What are 4 examples of cellular adaptation?

-hypertrophy

-hyperplasia

-Atrophy

-Metaplasia

**these are all reversible

3

What is metaplasia?

-a change in a cell's phenotype (adaptation)

e.g. metaplasia in airway of smokers

4

What happens to a cell if a nefarious stimulus persists or is severe?

-the cells undergo irreversible injury and cell death

5

What happens when a cell is continuously out of ATP?

-membrane injury:

-cellular constituents leak out of cell
-Ca2+ enters cell --> damage
-intracellular enzymes are released and activated

6

(T/F) Membrane injury only involves the cell membrane.

F. it also involves the membranes of mitochondria and other organelles

7

What happens when an injury causes a bunch of Ca ions to enter the cytosol of the cell?

Activates:

-ATPases
-Phospholipases
-Proteases
-Endonucleases

8

How can free radicals damage cells?

-lipid peroxidation of cell membrane

-inactivates enzymes

-causes DNA damage

9

With irreversible cell membrane injury which of the following will occur:

A. Influx of Na+ and Ca++
B. Influx of K+
C. Efflux of Na+
D. Efflux of Ca++

A. Influx of Na+ and Ca++

10

What are Caspases?

Enzymes that lead to apoptosis.Two Types:

-Initiator: (8&9) activate execution caspases in conjunction with other proteins

-Executor: disrupt cytoskeleton and degrade DNA

11

What is Bcl-2?

-part of a family of proteins that regulate cell growth

-ratio of members of family determines whether a cell will live or die

-affect mitochondrial permeability

12

Which members of the Bcl-2 family favor apoptosis?

-Bax

-Bad

others...

13

Which members of the Bcl-2 family inhibit apoptosis?

-Bcl-2

-Bcl-XL

others...

14

Which of the following is characteristic of apoptosis:

A. Inflammation
B. Large numbers of cells affected
C. Internucleosomal DNA breaks
D. Free radical damage

C. Internucleosomal DNA breaks

15

What is a Giemsa or Wright/Giemsa stain used on?

Blood smears

16

What must be maintained for a cell to continue living?

-Cell membrane must remain intact

-Aerobic metabolism --> ATP must continue

-Protein synthesis must continue

-Nuclear DNA integrity must be maintained

17

Is Cytochrome C associated with the intrinsic or extrinsic apoptosis pathway?

intrinsic

18

Loss of Bcl-2 can be seen in what major process?

A. inflammation
B. injury
C. repair
D. hemodynamic disturbance
E. neoplasia

E. Neoplasia

19

What is the cellular morphology of apoptosis?

-cell shrinkage

-nuclear chromatin condensation

-formation of blebs = apoptotic bodies

-phagocytosis of apoptotic bodies

20

What are the two features of a reversible cellular injury?

-Hydropic change (cellular swelling)

-Fatty change (Steatosis), increase in fat in cell due to interference w/ protein/fat metabolism

21

What is a hydropic change?

-increased water in the cell due to the loss of the Na/K pump, cellular swelling

22

What are the two types of irreversible cell injury?

-apoptosis

-Necrosis

23

What are the three possible histological findings of a cell nucleus going through necrosis/apoptosis?

-Karyolysis = paler staining

-Pyknosis = shrunken, dark staining

-Karyorrhexis = fragmentation

24

What happens histologically to a cell undergoing necrosis?

-the cytoplasm gets pinker

=an increase in eosinophilia

25

What are the four patterns of Necrosis?

-Coagulative necrosis

-Liquefactive necrosis (brain or abscess)

-Caseous necrosis (tuberculosis or fungi)

-Fat necrosis (pancreas most common, also mastitis)

26

What are the microscopic features of coagulative necrosis?

-cell outline/border remains

-more eosinophilic cytoplasm (redder)

-cytoplasmic structures indistinct

-nuclei absent

27

What are the gross and microscopic features of liquefactive necrosis?

Gross:
-soft, pus, fluid

Microscopic:
-no cell outlines remain
-"empty" space with/without granular pink material

28

What are the gross and microscopic features of caseous necrosis?

Gross:
-caseous = soft, cheese-like material

Microscopic:
- +/- indistinct cell outlines
-no nuclei
-amorphous pink material

29

What are the gross and microscopic features of Fat necrosis?

Gross:
-maybe soft
-areas of calcium deposits (gritty)

Microscopic:
-vague cell outlines may remain
-no nuclei
- +/- calcification (calcium + fat = saponification)

30

What happens to cells in a hypertrophic heart?

-cells cannot get any larger then rupture and die

31

What is the mechanism of atrophy?

-decreased protein synthesis

-usualy by ubiquitin-proteasome pathway

32

What is the mechanism of metaplasia?

-reprogramming of existing normal stem cells or undifferentiated mesenchymal cells

33

What is hemosiderin?

-a breakdown product of hemoglobin

-contains iron

34

What is lipofuscin?

a "wear & tear" pigment from membrane damage

35

What are the two types of calcification? What's the difference between them?

Dystrophic Calcification:
-deposition of calcium in damaged tissues

Metastatic Calcification:
-calcium deposited in normal tissue (due to high serum calcium)

36

What are Psammoma bodies?

-show up in ovarian tumors

-microscopic appearance of round laminated calcium nodules

37

How do you histologically change hydropic change from fatty change?

-both will have large white cells

-hydropic change cells still have nucleus in center

-fatty change cells are more circular, nucleus is not in middle of white

38

What type of necrosis is gangrene?

coagulative

39

Caseous necrosis is associate with which of the following?

A. TIssue ischemia
B. Fatty change
C. Pancreatitis
D. Tuberculosis

D. Tuberculosis

40

ENlargement of the thyroid gland because of increased levels of TSH is an example of:

A. Hypertrophy
B. Hyperplasia
C. Metaplasia
D. Atrophy

B. Hyperplasia

**Hypertrophy mostly occurs in muscle

41

WHat are the four naturally endogenous pigments?

-lipofuscin

-Melanin

-Hemosiderin

-Bilirubin