ALS

Question 1

describe ALS

Answer 1

Amytrtophic lateral sclerosis:
a progressive neurodegenerative disease where motor neurons in the brain and spinal cord die which affect abilit to walk, talk, swallow, and eventually breathe (casue of death)
- voluntary muscles no longer receive comands from the brain and atropy

Question 2

is what the life expectancy after diagonsis

Answer 2

2-5 years

Question 3

are most sprodadic or familial ?

Answer 3

90% sporadic

5-10% familial

Question 4

Lower Motor Neruron:
motor neurons in the ________ ____ horns of the spinal cord and their axons that inneravate skeletal muscles

Upper Motor Neuron:
carry motor output from _______ cortex and ________ to lower motor neuron in spinal cord and brainstem which in turn, project to muscles in the periphery

Answer 4

anterior gray horns
cerebral cortex
brainstem

Question 5

list the signs and symptoms for upper and lower motor neurons

Answer 5

upper signs: 
- spasticity 
- slowed rapid mvt 
- increased reflexes 
- gait disorder 
upper symptoms: 
- stiffness, slowness, incoordination of mvt
- spontaneous clonus
- spontaneous flexor spasms 

lower signs: 
- weakness
- gait disorder
- reduced reflexes
- muscle atrophy/ fasciculations 
lower symptoms: 
- weakness and atrophy
- fasciculations
- cramps

Question 6

for definite SLA, signs are in atleast 3 regions out of 4 whhich are?

Answer 6

bulbar
cervical
thoracic
lumbosacral

Question 7

what is SOD1?

Answer 7

super oxide dismutase

• an enzyme
• impt antioxidant

Question 8

what are functions of SOD1? (3)

Answer 8

1. an enzyme that repairs cells and redcues the damage done by superoxide (the most common free radical)
2. acts as an antiinflammatory
3. catalyzes the dismutation of superoxide into oxygen and hygroden peroxide

Question 9

what are some cellular processes that are involved in neuronal death from ALS?

Answer 9

• glutamate receptors mediated excitotoxicity
• disruption of spinal inhibitory circuits
• inflammatory events
• axonal transport deficits
• oxidative stress
• mitochondrial dysfunction
• protein aggregation and misfolding

Question 10

what is the dying Forward hypothesis?

Answer 10

that ALS is a disorder of the corticomotorneurons what mediate anterior horn cell degeneration via an anterograde glutamate excitotoxic mechanism

Question 11

what is dying back hypothesis?

Answer 11

deficiency of specific motor neurotrophic ffactors, which are normally released by postsynaptic cells and retrogradely transported up the presynaptic axon to the cell body

Question 12

what is the indepdent degeneration hypothesis

Answer 12

upper and lowe rmotor neuron degeneration can be independent processes