2: Neuropathology 1 Flashcards Preview

Neurology Week 4 2018/19 > 2: Neuropathology 1 > Flashcards

Flashcards in 2: Neuropathology 1 Deck (44)
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1

What germ cell layer do neurons and glial cells come from?

Ectoderm

2

Which germ cell layer do microglia come from?

Mesoderm

3

Necrosis is ___ death of brain cells and occurs in which brain disease?

rapid

sudden failure e.g stroke

4

Atrophy is a ___ reduction in brain size.

Is it normal?

slow

Depends - occurs with age, but is accelerated in diseases such as Alzheimer's

5

What happens to neurons histologically in acute injury? 

Nuclei shrink and angulate

Nucleolus is lost

Cytoplasm turns red

6

___ neurons are indicative of acute neuronal injury.

Red

7

Which types of acute injury cause red neuronal death?

Hypoxia

Infarction

8

What is the role of astrocytes in the CNS?

Support cells

Maintain homeostasis, maintain BBB, role in repair

9

What is reactive gliosis?

Which cells undergo it?

What does it look like?

Non-specific reaction to CNS injury by glial cells

Glial cells (astrocytes, microglia, ependymal cells, oligodendrocytes)

Hypertrophy and hyperplasia, nucleus enlarges

 

10

In demyelinating diseases (e.g MS), the conduction velocity of neurons (increases / decreases).

decreases

11

What process do astrocytes undergo in response to injury?

Reactive gliosis

like all glial cells

12

What happens to astrocytes in gliosis?

Hypertrophy

Hyperplasia

13

Which important processes do

a) neurons

b) glial cells

undergo in response to injury?

a) "Red neuron" reaction

b) Reactive gliosis 

14

What are the role of microglia in the CNS?

Immune surveillance

Phagocytosis

15

Which immune cell are microglia very similar to?

Macrophages

do the same job i.e phagocytosis, just in the brain

16

Which state causes acute brain injury and occurs in stroke, trauma and cardiac arrest?

Hypoxia

17

Which percentage of inhaled oxygen is used by the brain?

20%

18

Why do neurons depolarise after extended hypoxia?

Which neurotransmitter is released in response to this abnormal depolarisation?

Which ion then enters the neuron

Na/K ATPase stops working - so Na accumulates inside the cell, causing a depolarisation

Glutamate (excitatory)

Ca2+

19

What is excitotoxicity?

What triggers it?

Process by which neurons are killed by excessive glutamate Ca2+ release

Extended hypoxia - Na/KATPase fails - Depolarisation - Glutamate release - Ca2+ influx - Release of endotoxins

20

Various types of swelling, or ___, occur in response to brain injury.

oedema

21

What is vasogenic oedema?

Breakdown of the BBB in infarcted areas of the brain allows water, ions and protein to filter out, causing swelling

22

What is cytotoxic oedema?

Hypoxic cells lose function of their sodium-potassium pump

Sodium accumulates in the cell

So water and chloride ions follow down the osmotic gradient

Causing the cell to swell

Protein can also get in through the wrecked cell membrane

23

Oedema causes ___ of brain tissue.

compression

24

What can happen to the brain if intracranial pressure increases too much?

Herniation

which tends to be fatal

25

What is haemorrhagic conversion?

Blood vessels weakened by an ischaemic stroke rupture, causing bleeding

26

Which three processes cause compression, contributing to complications following a brain injury?

Cytotoxic oedema

Vasogenic oedema

Haemorrhagic conversion

27

The area of brain affected by a stroke depends on the ___ which are affected.

arteries

28

What is the average BP of the brain circulation?

20 mmHg

29

What pathologies of blood vessels cause stroke?

Infarction

Haemorrhage

AVM

Aneurysm

Dissection

30

What is a cardio risk factor for stroke?

Hypertension