Pathology

Question 1

what is hyperplasia?

Answer 1

an increase in cell number, in response to an external response. Will regress on withdrawl of a stimulus

Question 2

mechanism of hyperplasia?

Answer 2

• production of increased growth factor
• increased growth factor receptors
• genes encoding for growth factors and cell cycles switch on

Question 3

what do areas in lymph nodes undergo in response to infection?

Answer 3

hyperplasia

Question 4

what is hyperplastic and metaplastic tissue at risk of?

Answer 4

at risk of the development of cancer

Question 5

what is hypertrophy?

Answer 5

an increase in cell size

Question 6

what is atrophy?

Answer 6

reduction in cell size

Question 7

mechanism for atrophy?

Answer 7

• protein degradation

- hormones can promote/oppose atrophy

Question 8

what is metaplasia?

Answer 8

reversible change from one mature cell type to another mature cell type

Question 9

in acute inflam, what mediates vascular vasodilation?

Answer 9

histamine and nitric oxide

Question 10

steps of binding of neutrophils to endothelial cell wall

Answer 10

• binding due to CAMs on neutrophils and cell wall
• firstly lightly via selectins (on endothelial wall)
• tighter binding via ICAMs on endothelial cell with integrins on neutrophil

Question 11

what increases selectin expression?

Answer 11

histamine and thrombin

Question 12

what increases endothelial cell expression of VCAM and ICAM?

Answer 12

TNF and IL-1

Question 13

clinical features of acute inflam?

Answer 13

rubor, dolor, calor, tumor, loss of function

Question 14

what does a neutrophil look like?

Answer 14

polymorph granulocyte

Question 15

what is suppuration?

Answer 15

pus formation

Question 16

when is healing by organisation favoured?

Answer 16

when damage goes beyond the basement membrane

Question 17

process of granulation tissue formation

Answer 17

• infiltration by capillaries and myofibroblasts

- collagen and smooth muscle cell deposit

Question 18

what characterises chronic inflam?

Answer 18

presence of lymphocytes

Question 19

what is a granuloma?

Answer 19

aggregate of epitheloid histiocytes

Question 20

what is necrosis?

Answer 20

premature death of cells in living tissue, always pathological

Question 21

what is coagulative necrosis and where is it seen?

Answer 21

cell death with preservation of the cell outline

seen in cardiac muscle

Question 22

what is liquefactive necrosis and where is it seen?

Answer 22

cell death leaving behind a liquid viscous mass

seen in the brain

Question 23

what is caseous necrosis and where is it seen?

Answer 23

granulomatous inflam with central necrosis

seen in TB

Question 24

what is apoptosis?

Answer 24

programmed cell death in response to specific signals, requires energy

Question 25

extrinsic pathway of apoptosis?

Answer 25

• mediated by TNF, Fas ligand (death receptors)

- bind to death receptors on the cell surface

Question 26

intrinsic pathway of apoptosis?

Answer 26

• growth signals promote anti apoptotic molecules in the mitochondrial membrane
• bax and bak are pro apoptotic
• induce the release of cytochrome C
• this stimulates caspases

Question 27

what is p53?

Answer 27

p53 can sense DNA damage, halt cell cycle and repair/induce apoptosis

Question 28

what is dysplasia?

Answer 28

the enlargement of an organ or tissue by the proliferation of cells of an abnormal type, as a developmental disorder or an early stage in the development of cancer

Question 29

causes of cellular ageing?

Answer 29

• oxidative stress

- accumulation of metabolism by products

Question 30

what are telomeres?

Answer 30

chromosomes capped with TTAGGG repeats, stops degradation