Neurodegenerative Diseases Flashcards
(24 cards)
What is the most common neurodegenerative disease of the cortex?
Alzheimers
What is the prognosis for AD?
3-20 years
What is the incidence of AD among 85 year olds?
40%
What do AD patients usually die from?
infection - often pneumonia
What are the grossa and macroscopic findings in AD?
gross = brain atrophy microscopic = tangles and plaques
Where in the cortex does AD usually start? Progresses?
starts in the hippocampus, then to the frontal lobe, then to the rest of the cortex
What are the plaques made of in AD?
AB amyloid
What are the tangles made of and where are they located?
tau protein
located in the neuron
What are some other pathological changes you see with AD?
- neuronal loss and gliosis
- cerebral amyloid angiopathy
- granulovacuolar degeneration
- hirano bodies
How can you stain for amyloid?
Congo red will stain is slightly redder, but when you turn the slide to a certain angle, it will look green
What does the AB peptide come from in AD?
It’s an alternate cleaving of amyloid precursor protein.
it’s usually cleaved by alpha secretase and gamma secretase into dissolvable parts. But in AD, it’s cleaved by gamma and beta secretase. This forms an AB segment that is not soluble and will form aggregates
What forms first in AD, the amyloid plaques or the tangles?
the plaques are first and the tau tangles are secondary - maybe directly caused by the plaques damaging the microtubules
What parts of the brain are affected in Pick Disease?
It’s a distinctive dementia that affects the frontal lobe and temporal lobes only
What do you see on pathology in Pick Disease?
you get severe atrophy of the frontal and temporal lobes with neuronal loss, swolen neurons (pick cells) with cytoplasmic neuronal inclusions (pick bodies)
True or false: Parkinsons’s disease diminishes life expectancy.
false
What will you see on pathology in PD?
loss of pigemented neurons causing pallor of substantia nigra
Lewy body formation in the remaining neurons
What protein is contained in Lewy Bodies (but we don’t really know what it does?
alpha-synuclein
What degenerates in amyotrophic lateral sclerosis?
motor neurons
Is cognition and sensation affected in ALS?
Nope - just motor
What is usually the cause of death in ALS?
Death occurs usually witnin 2-3 years due to the respiratory compromise
“Progressive musclar artophy” is a subtype of ALS that is characterized by what?
loss of upper motor neurons only - not LMNs
Progressive bulbar palsy is a subtype of ALS that is characterized by what?
cranial nerve signs - especially difficulty swallowing and speaking
What proteins are potentially mutated in ALS?
superoxide dismutase ubiquilin 2 (a housekeeping protein)
What will you see on pathology in ALS?
thin anterior roots of spinal cord
reduction in anterior horne neurons
skeletal muscles atrophies
degeneration of corticospinal tracts
