Growth, Cell Death and Neoplasia Flashcards Preview

Phase 2a - Introductory Clinical Sciences > Growth, Cell Death and Neoplasia > Flashcards

Flashcards in Growth, Cell Death and Neoplasia Deck (103)
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1

define apoptosis

programmed cell death

2

define necrosis

traumatic cell death - unintended cell death in response to cellular injury

3

why do we need apoptosis?

for continuous renewal of cells, working alongside mitosis

4

name some inhibitors of apoptosis

growth factors
extracellular cell matrix
sex steroids
some viral proteins

5

name some inducers of apoptosis

growth factor withdrawal
loss of attachment of ECM
glucocorticoids
some viruses
free radicals
ionising radiation
DNA damage

6

give some examples of when apoptosis is crucial for normal growth - and what occurs if apoptosis fails

separating of fingers - interdigital cell death - syndactyl (webbed fingers)
removal of redundant epithelium on fusion of palatine processes in roof of mouth - cleft palate

7

what is coagulative necrosis?

most common.
dead tissue is swollen and firm, then later becomes soft - digestion of macrophages

8

what is colliquative (liquefactive) necrosis?

occurs in brain due to lack of supporting stroma - necrotic tissue liquefies

9

what is caseous necrosis?

dead tissue is completely structureless. histology shows amorphous eosinophilic area with haematoxyphilic nuclear debris.
seen in TB.

10

what is gangrene?

necrosis with putrefaction of tissues. tissues appear black.

11

what is fibrinoid necrosis?

occurs in malignant hypertension - increased arterial pressure results in necrosis of SM wall.
eosinophilic and fibrinous deposits seen.

12

what is fat necrosis?

focal adipose tissue destruction due to direct trauma, or enzymatic lipolysis (seen in acute pancreatitis)

13

define hypertrophy

increase in size of a tissue caused by increase in SIZE of the constituent cells

14

define hyperplasia

increase in size of a tissue caused by an increase in NUMBER of constituent cells - decrease in apoptosis

15

define atrophy

decrease in size of a tissue caused by a decrease in NUMBER or SIZE of constituent cells - apoptosis

16

define metaplasia

change in differentiation of a cell from one fully-differentiated type to another

17

define dysplasia

morphological changes seen in cells in the progression to becoming cancer

18

give some examples of physiological hypertrophy/hyperplasia

muscle hypertrophy in athletes - in limbs and LV of heart.
hyperplasia of breast tissue at puberty and in pregnancy/lactation.
hypertrophy and hyperplasia of uterine smooth muscle at puberty/pregnancy.

19

give some examples of conditions involving pathological hypertrophy/hyperplasia

RVH/LVH.
gynaecomastia.
prostate hyperplasia.
follicular epithelial hyperplasia e.g. in Graves' disease (thyroid)

20

define congenital

present at birth - not necessarily inherited, foetus is affected by environmental factors in womb (eg FAS)

21

give some examples of changes to the body that are typical of ageing

loss of dermal elastosis
osteoporosis
cataracts
senile dementia
sarcopaenia (loss of skeletal muscle mass/strength)
deafness

22

define carcinogenesis

transformation of normal cells to neoplastic cells through permanent genetic alterations or mututations
- malignant tumours

23

define oncogenesis

formation of benign and malignant tumours

24

define carcinogen

agents known/suspected to cause cancer - malignant tumours.
act on DNA - mutagenic

25

define oncogenic

agents known/suspected to cause tumours - benign or malignant

26

what problems are presented by attempts to identify carcinogens?

latent interval may be decades.
environment is complex - difficult to isolate one factor.
ethical constraints - can't deliberately give people a suspected carcinogen as part of a study

27

list the classes of carcinogen

chemical
viral
ionising/non-ionising radiation
hormones, parasites and mycotoxins
misc.

28

define neoplasm

lesion resulting from autonomous (or relatively autonomous) abnormal growth of cells which persists after the initiating stimulus has been removed
A NEW GROWTH

29

what are the features of neoplasia?

autonomous
abnormal
persistent
new growth

30

what makes a neoplasm malignant?

if they invade surrounding tissues, and are able to metastasise/spread to other tissues