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Flashcards in Prions Deck (30):
1

what are the common pathologies seen in transmissible spongiform encephalopathies

multifocal spongiform changes
amyloid
astrogliosis
neuronal loss

2

what is the prion protein? where is it found?

209 amino acid glycoprotein that is expressed on the cell surface and is anchored ther by FA

in a single exon on chrom 20

**highly expressed in NEURON and LYMPHOCYTES**

3

nml function of PrPc

inhibit BACE1 activity which inhibits the formation of beta amyloid

4

differences in __ cause PrP-Sc to be ____

folding --> resistant to proteases

5

how does a folding difference lead to a diseased state?

aggragates form; these are unstable and cause the neuron to undergo APOPTOSIS

6

mice lacking ___ are resistant to prion infection. Significance?

PrP-C, meaning PrP-C is needed for the formation of PrP-Sc

**PrP-Sc forms when an intermediate of PrP-C interacts with another PrP-Sc which acts as a template for all the other abn proteins = CHAIN REACTION

7

what explain the late onset of sporadic CJD

PrP-C is greatly favored and it takes a long tine for the rare, pathogenic (PrP-Sc) to form (age dept mutation?)

8

what dictates the final conformation a prion protein assumes

template prion NOT the amino acid sequence of the protien

9

What is scrapie and what is its significance to human prion disease?

subacute, progressive ataxia in sheep and goats that showed transmission occurred via the alimentary tract

10

clinical features of Creutzfeldt-Jakob disease (CJD)

dementia, myoclonus, ataxia, akinetic mutism

11

most common type of CLD (sporadic, familial, or iatrogenic)

sporadic

12

average age of onset in sporadic and familial CLD

sporadic = 60
familial = 45 to 50

13

who lives longer after diagnosis, those with sporadic or familial CJD

familial (2-4 yrs vs 1 yr)

14

mode of inheritance for familial CJD

AD
there are specific mutations in the prion protein that appear to facilitate the conversion of C to Sc

15

where do spongiform changes take place with prion disease

cerebellum

16

what diagnostic fining is specific to CLD

periodic complexes on EEG

17

clinical features of GSS dz

gait abn and ataxia
DEMENTIA IS LESS COMMON

18

etiology of GSS

mutation at codon 102 of prion protein and has AD pattern of inheritence

19

clinical features of FFI

sleep disturbances and autonomic dysfunction

20

etiology of FFI

mutation in codons 129 and 178 with AD pattern of inheritance

21

vCJD is the same dz as

mad cow (aka BSE)

22

etiology of vCJD

consuption of contaminated beef (also blood transfusions noted)

23

sources of iatrogenic CJD

dural and corneal grafts
pituitary derived hGH

24

avg age on onset for vCJD

29!!! VERY YOUNG (younger than familial/genetic etiologies= familial CJD, FFI, GSS)

25

clinical characteristics of vCJD

anxiety, depression, visual problems

26

all pts with vCLD had what gene polymorphism in common

homologous for menthionine at codon 129 of PrP

27

histo changes unique to vCJD

florid plaques and spingiform changes in BASAL GANGLIA

28

subcellular location of PrPc vs PrPSc

C = cell surface and Sc = intracellular vesicles

29

which prion diseases are assc with plaques?

GSS and vCJD

30

which prion diseases are assc with cerebellar spongiform changes

CJD, GSS

*vCJD are in basal ganglia