CNS

Question 1

what is necessary to ensure the differentiation of neural and epidermal tisse

Answer 1

closure of the neural tube (fully)

Question 2

which direction do neuron migrate in the brain, and where

Answer 2

from the central lumen to the outer edge (white matter)

in cerebellum this continues 2 mths after birth

Question 3

name the 3 primary vesicles of the developing brain and the additional 2 secondary ones

Answer 3

• pro, mesen and rhombencephalon

- telen and diencephalin

Question 4

name the 2 biggest sulci on the brain

Answer 4

tentorium cerebelli

falx cerebri

Question 5

what is the nissyl substance

Answer 5

rER in the cytoplasm of neurons

Question 6

what is substantia nigra

Answer 6

neuromelanin pigm used as a NT in primates

Question 7

what marker can be identified by IHC on astrocytes

Answer 7

GFAP

Question 8

what is the role of astrocytes

Answer 8

BBB
uptake and recycle NT
maintain pH
support metabolic needs
help neuronal migration

Question 9

describe the diff stages of microglia

Answer 9

inactive - rammified
active - rod, comma nuc, mphages
de-activated (when finished), granular - gitter cells

Question 10

what is malacia

Answer 10

gross appearance of necrosis of the brain

Question 11

where in the brain can you find poss fibrosis

Answer 11

nowhere - meninges can tho

Question 12

why are neurones easily damage

Answer 12

v active
cant differentiate of prolif
axons and dendrites extend far from the soma
constantly inhib or stim

Question 13

why do red hypoxic neurones occur

Answer 13

over excitment, inc ca++ prod or just in hypoxic states**

Question 14

what is the neuronal response to oxidatie stress

Answer 14

chromatolysis (massive pale cytoplasm in soma, tiny peripheral nucleus)

Question 15

how do you describe an inc in astrocyte number and vole

Answer 15

number = astrogliosis
vol = astrocytosis

Question 16

what are the 2 forms of myeline damage/degen

Answer 16

1ry - if the oligo is damaged –> dysfct myelin (leukodystrophy)
2ry - if its the myelin thats damaged

Question 17

bane the 4 types of CNS oedema

Answer 17

1. cytotoc - altered cyto metab, ballooning degen
2. vasogenic - vascular damage + extracellular fluidin WM
3. hydrostatic - inc fluid in Ventricles + extra-cellular WM
4. hypo-osmotic - intra + extra fluid in W+G matter

Question 18

what are the general affects of vascular pathology in brain, seen by what

Answer 18

asymetrical
malacia and haem+ (probs)
acute, non-progressive neural issues

Question 19

what is penumbra

Answer 19

the area around an area of complete ischaemia, which will suffer repurfusion injury if too quick

Question 20

how can an infarct be caused in the brain

Answer 20

• mis injection of carotid a causing thrombembolism
• rupture of f-cartilagenous disk
• ichaemia due to reduced blood from stenosis of a caused by calcinosis sidero (in t. media=blue)

Question 21

how can path access the brain

Answer 21

• retrograde axonal transm (rabies, listeria)
• deposit IC at the BBB (FCoV)
• infec endothelial cells (CSF)
• within other cells (toxo, viruses)
• accum wi vessels (bact)

Question 22

what are the characteristics of viral inf

Answer 22

• targeted areas
• neuronophagic nodules
• glial nodule (n-phagic nodules but wo a neuron involved)
• non-supperative

Question 23

how do you tell diff PM of rabies and pseudorabies, as both get non-supp polioencephalomyelitis

Answer 23

rabies = IC inclusion and negri bodies in hippocampus (Carnivores) or perkinje cells (herbiv) 
pseudorabies = swine herpes 1 = IN inclusions

Question 24

what is swine polioecephalomyelitis trophic for

Answer 24

LMN

Question 25

what virus causes 1ry demyelination leukoencephalitis

Answer 25

distemper (morbillivirus)

Question 26

what inclusion bodies cn be seen in distemper

Answer 26

IN and IC in astrocytes

Question 27

what are signs of chronic inflam in the CNS

Answer 27

cavitation | malacia

Question 28

where does borna virus inhabit

Answer 28

hippoc cerebral cortex of H bstem of Cat

Question 29

what family is west nile virus

Answer 29

flaviridae (same as louping ill)

Question 30

where does west nile virus usually inhabit

Answer 30

thoraco-lumbar spinal cord | but can extend to cd bstem

Question 31

name a lentivirus which translates and 'dyspnoea and wasting'

Answer 31

maedi-visna

Question 32

what lesions does maedi-visna cause

Answer 32

granulomatous leukoencephalomyelitis chondroititis meningitis

Question 33

what does FCoV cause

Answer 33

FIP IC deposits --> vasculitis pyogranulomatous meningo-chorio-subependymitis pyogranuloma in eye, due to optic n infection

Question 34

what transmits louping ill

Answer 34

ixodes ricinus

Question 35

where does louping ill infect in the brain, and what lesions

Answer 35

non supp polioencephalitis | loves purkinje cells

Question 36

what lesions might be seen in the spinal cord of a horse with EHV-1 and what other effects may happen

Answer 36

petechial haem+ in both W+G matter vascultis abortion or ataxia

Question 37

what are the typical signs of bacterial inflm of CNS

Answer 37

- PMNs (supperative) - chromatolysis - gliotic reaction/gliosis - disseminate, F (abscess) or MF lesions

Question 38

what causes sleeper syndrome in young cattle in autumn

Answer 38

histophilus somni (assoc with pneumonia too)

Question 39

what are the lesions caused by histophilus somni

Answer 39

thrombotic mengingo-encephalitis, focal purulent meningitis and MF necrotising haem+ encephalitis *thrombus is main cause of path throughout the body

Question 40

desc the appearance of meningitis

Answer 40

above dura - MF supperative inflam +- fibrosis (if v chronic) below dura - heam+ and pus *often spreads from ethmoid cavity from inner ear infection, enlarged tympanic bullae suggests chronic infection

Question 41

describe the patho of listeriosis

Answer 41

- oral mucosa --> V or VII at Bstem via retrograde axonal transport - axons = spongiosis - MF-C microabscesses where neurones once were - bilat, not symmet - hyperaemia

Question 42

desc lesions of mycotic (candida, aspergillus) encephalitis

Answer 42

*hallmark = necro vasculitis and thrombosis | MF granulomatous meningo-encephalitis

Question 43

what microsporidium that infects rabbits commonly can be differentiated from vestibular dz using a spin test (alan..) and what type of lesion does it make

Answer 43

encephalitozoon cuniculi | granulomatous encephalitis

Question 44

how come toxo does not always result in neuro dz if the bradyz are in the neural tissue unless the animal is immunocomp. what dz does ensue in this situation

Answer 44

behavioural changes, impaired reflexes - mkes the mouse easier to catch is the theory. also myocarditis and myositis.

Question 45

what lesion does toxo gondii cause

Answer 45

young - non supp polioencephalitis | adult - necrotising, granulomatous encephalitis

Question 46

what does neospora do

Answer 46

similar to toxo - causes ataxia in dam, paresis in pups etc

Question 47

what protozoa causes eq protozoal encephalomyelitis

Answer 47

sarcocystis neurona (targets motor n)

Question 48

desc the lesion of taenia multiceps

Answer 48

sheep cerebral coeneurosis 1 x fluid filled cyst - 'walk in circles'

Question 49

what causes granulomatous meningo-encephalitis

Answer 49

AI dz of anti-GFAP (on all glial cells eg astrocytes, ependymal cells..)

Question 50

what is the hallmark of GME

Answer 50

perivascular cuffs of mphages which are then surrounded by l#