Term
| Describe the onset and progression of Huntington's disease |
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Definition
- gradual onset
- progressive development |
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Term
| What are the main symptoms of Huntington's? |
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Definition
| chorea (a dyskinesia) and dementia |
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Term
| Who is affected by Huntington's? |
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Definition
Usually starts at 30-50 years
juvenile onset much more severe
death in 10-20 years |
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Term
| Describe the symptomatic signs of dementia |
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Definition
irritability
moodiness
antisocial behaviour |
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Term
| Describe the symptomatic signs of chorea |
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Definition
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Term
| What do CT/MRI scans show of someone with Huntington's? |
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Definition
atrophy to the cerebellar
loss of striata neurones (post-mortem)
genetic disorder |
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Term
| Describe the pathology of Huntington's |
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Definition
1. selective cell loss in cerebral cortex and corpus striatum
2. degenerated medium sized spiny neurones that contain GABA and enkephalin degenerate
3. reductions in GABA dehydrogenase and GABA |
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Term
| What changes occur in Huntington's with regards to neurotransmitters? |
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Definition
decreased GABA and GABA dehydrogenase
decreased acetylcholine and acetylcholinetransferase
either no change or slight increase in dopaminergic neurones |
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Term
| What are the causes of Huntington's disease? |
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Definition
- autosomal dominant disorder (offspring have 50% if one parent has it)
- gene defect on short arm of chromosome 4 |
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Term
| Describe the gene defect responsible for Huntington's |
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Definition
- gene defect on short arm of chromosome 4
- locus 4p16.3 codes for protein dubbed "Huntingtin'
- gives rise to an expanded and repeated CAG repeat
- polyglutamine disorder
- 36 or more relates = HD, 40+ = severe (earlier onset and more aggressive) |
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Term
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Definition
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Term
|
Definition
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Term
|
Definition
affects men twice as much
starts at 45-75 years
death in 2-12 years (usually 4-7 years) |
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Term
|
Definition
| aspiration (breathing food in their lungs and getting infections) or inanition (unable to take food or water in) |
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Term
| What are the symptoms of PSP? |
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Definition
- progressive dementia (irritability)
- ophthalmoplegia (vertical gaze goes then horizontal)
- impaired balance/posture
- pseudobulbar palsy
- Exaggerated and inappropriate emotional responses |
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Term
| Explain impaired balance in PSP |
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Definition
unexplained falls occur early
neck extended, rigid to flexion |
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Term
| Explain pseudobulbar palsy in PSP |
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Definition
facial weakness
dysarthria (speech)
dysphagia (swallowing)
exaggerated gag reflex |
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Term
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Definition
- neurodegeneration
- NFT in midbrain, pons basal ganglia, dentate nuclei of cerebellum
- decreased dopaminergic neurones in caudate nucleus and cerebellum |
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Term
| What symptoms, similar to PD do PSP patients sometime exhibit? |
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Definition
limb rigidity
bradykinesia
hyperreflexia |
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Term
| Describe Cortical Basal Ganglionic Degeneration |
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Definition
- rare
- non-inherited/familial
- late onset in middle age/elderly |
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Term
| What are the symptoms of CBGD? |
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Definition
- bradykinesia/rigidity (like PD)
- apraxia/clumsiness
- postural instability
- myoclonus
- often assymetric
- speech (aphasia, apraxia, dysarthria) |
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Term
| What are the symptoms of CBGD? |
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Definition
- atrophy in frontal and parietal cortex
- cell loss and gliosis in cortex, substantial nigra, locus eeruleus, thalamus, red nucleus, lentiform nucleus |
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Term
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Definition
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Term
| What is motor neurone disease? |
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Definition
Group of similar disorders
Amyotrophic lateral sclerosis (ALS)
Primary lateral sclerosis (PLS)
Progressive muscular atrophy (PMA)
Pseudobulbar palsy (PBP)
Progressive bulbar palsy (PrBP) |
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Term
| What is the difference between upper and lower motor neurones? |
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Definition
U: originate in moto area of the cortex
L: cell bodies of which are in the spinal cord |
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Term
| In which motor diseases do both upper and lower motor neurones degenerate? |
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Definition
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Term
| In which motor diseases do only upper motor neurones degenerate? |
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Definition
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Term
| In which motor diseases do only lower motor neurones degenerate? |
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Definition
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Term
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Definition
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Term
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Definition
- degeneration of upper and lower motor neurones and those anterior horn cells
- muscle denervation |
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Term
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Definition
90-95% sporadic - may be due to glutamate excitatotoxicity that kills off neurones
5-10% due to familial mutations in superoxide dismutase (SOD1) |
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Term
| What are the effects of motor denervation? |
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Definition
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Term
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Definition
very progressive
fatal in 3-5 years |
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Term
| How does ALS cause death? |
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Definition
| The most common cause of death for people with ALS is respiratory failure. |
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Term
| WHat are the early symptoms of ALS? |
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Definition
1. bulbar 20% - chewing, swallowing, breathing, speaking
2. upper extremities 40%
3. lower extremities 40%
4. muscle wasting and weakness |
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Term
| What doesn't change in ALS? |
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Definition
- no sensory changes
- electromyograph similar changes to chronic partial denervation
- motor and sensory nerve conduction velocity unchanged |
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Term
| What is the effect on the affected muscles? |
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Definition
| easily tired, stiff, twitching |
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