10-22 L1 Neurodegenerative disease of myelin Flashcards
(25 cards)
Whats the most common cause of dementia?
- Alzheimer’s disease (62%)
- Multi-infarct dementia (17%)
- Diffuse lewy body disease (4%)
Age related accumulations of cytoplasmic filaments are:
- Neurofibrillary tangles
- Neuritic (senile) plaques
- Lewy bodies
Alzheimer’s disease
- 2F:1M
- Most cases are sporadic
Alzheimeris pt will be asymptomatic until how much neurons are left in the brain?
20%
What is gross changes in the brain are seen with AD?
- Brain weight decrease (<1,000 g)
-
Cerebral cortical atrophy
- Loss of gray and white matter
- ventricular dilation
- Brainstem & spinal cord normal
What are the 5 histological changes seen in the cerebral cortex and hippocampus in AD pts?
- Neuritic plaques
- Neurofibrillary tangles
- Granulovacuolar degeneration
- Congophilic angiopathy: Beta-amyloid
- Hirano bodies
Name the three ways that AB is cleard from teh brain:
- Edocytosis (astrocytes and microglial cells)
- Enzymatic degradation
- Drained along periarterial spaces
Describe the frontal lobe degeneration (initial stage and late stage)
- Initial stage
- Overactive, restless, distractible, disinhibited
- apathetic, inert, emotionally blunted
- Late stage
- Gradual reduction in speech (mutism)
- Akinesia and rigidity
Huntington’s disease
- chromosome
- genetic identification
- onset
- gross discription
- Chromosome 4 mutation
- consists of an expanded unstable trinucleotide (CAG) repeats
- greater the number of nucleotides greater the onset
- marked atrophy of the caudate nucleus
Parkinson’s disease
- pathology
- treatment
- Pathology
- substantia nigra: affects dopamine-synthesizing neurons w/loss of balance between direct and indirect pathwyas
- locus ceruleus
- other brainstem nuclei
- Treatment
- Replacement with L-dopa
ALS
Amyotrophic lateral sclerosis
- type of lesion
- m v f
- onset
- cause
- chromosome
- codes for what
- UMN & LMN
- M>F
- >40 yr
- 90% sporadic, 10% familial
- chromosome 21
- superoxide mutase (SOD1)
Progressive bulbar palsy
if degeneration involves predominantly the cranial nuclei with resulting dysarthria, dysphasia, and respiratory compromise
Progressive muscular atrophy
predominant LMN involvement
Primary lateral sclerosis
predominant UMN/corticospinal tract involvement
What is the most common autosomal ataxia?
Friedreich’s ataxia
Friedreich’s ataxia
- def
- pathology
- chromosome
- genetic repeat sequence
- a nuclear encoded protein active in the mitochondria where it is involved in iron homeostasis
- mitochondrial iron accumulation
- chromosome 9
- GAA trinucleotide (200-1000 repeats)
Whats the difference b/t Hereditary CJD and iatrogenic CJD?
- Hereditary CJD (5-10%)
- family hx
- genetic mutation (+)
- Iatrogenic CJD
- Exposure to CNS tissue
- usually through medical procedures
- Transmitted vis Human GH treatment
- Not transmittable through causal contact
- Exposure to CNS tissue
Fatal Familial insomnia (FFI)
-
degeneration of the thalamus
- (via mutation of a gene and production of an infectious prion.
- symptoms
- can’t sleep
- inability to feel pain
- poor reflexes
- dementia
What stain is used to stain MS (Multiple sclerosis)
Luxol Fast Blue (LFB)
Pts with long standing MS present with what?
- cerebral atrophy
- hydrocephalus ex vacuo
- optic nerves and chiasm (may be grossly atrophic)
What disease is commonly seen with ‘knife like’ gyri of the frontal lobe.
Pick’s disease
Where is the most distribution of neuritic placues in the cerebral cortex
Parietal and temporal lobes
Metachromatic leukodystrophy
- Age
- Genetics
- Cellular derangement
- Morphological feature
- Age: children (1-4 yo)
- Genetics: autosomal recessive
- Cellular derangement: def. of aryl-sulfatase-A
- Morphological feature: Metachromasia
(Krabbe’s) Globoid cell leukodystrophy
- Age
- Genetics
- Cellular derangement
- Morphological feature
- Age: Infants (<1 yr)
- Genetics: autosomal recessive
- **Cellular derangement: **def. of galactocerebroside-beta-galactosidase
- Morphological feature: Globoid cells
