55 陳冠博 62 陳夢蝶 指導老師 : 周淑娥 助教 : 徐永強. Mental Deterioration/...

55 陳冠博62 陳夢蝶

指導老師 : 周淑娥助教 : 徐永強

Mental Deterioration/ Dementia Age related= 10% at age 65, 35% at age 85 Symptoms:

Confusion Memory loss + can’t acquire new memories Language breakdown Unable to recognize people>

Suspicion + Hostility Gradual loss of function (motor) > difficulty speaking,

swallowing and walking

Hippocampus

Patient’s brain tissues have decreased number of neurons and synapse.

Plaques ： abnormal proteins that form between neurons

tangles ： irregular proteins that form within the neurons

APP

α andβSecretase

α and γSecretase

Aβ40

Aβ42

Easily dissociate

Easily dissociate

Plaques

Difficult to dissociate

Difficult to dissociate

Neuron’s transport system collapse

Microtubules disintegrate

Form neurofibrillary tangles inside nerve cell bodies

Hyperphosphrylate tau pairs with other tau

Neuron’s transport system collapse

Axonal transport disruptions

Age-related myelin breakdown

Microtubules disintegrate

Neuron deaths Shrinkage of tissue Hard to identify while alive Postmortem(屍檢 ) finding can identify

Alzheimer’s: 1. Amyloid plaque 2. Neurofibriallary tanglesCURES?No cure. Only drugs to relieve symptoms>- anti-acetylcholiesterase- Memantine(Namenda)

Age related= 1% at age 65, 5% at age 85 Motor Disorder Symptoms

Resting tremor Bradykinesia Rigidity +Flexed posture

-> postural instability Shuffling gait Forward-flexed posture when walking Mask-like face, small handwriting

Cause: Neurons in the midbrain that normally release

dopamine at synapse of basal nuclei and substantia nigra died

Detailed version alpha-synuclein (SNCA) + ubiquitin= lewy

bodies= accumulate

Cure?No cure. Attempts= brain surgery, deep-brain stimulation,

L-dopa, and dopamine-secreting neuron implantation.

L-DOPA (L-3,4-dihydroxyphenylalanine) naturally-occurring dietary supplement and psychoactive

drug found in certain kinds of food and herbs synthesized from L-tyrosine in the mammalian body and

brain> enter CNS> converted to dopamine L-DOPA can cross blood-brain barrier, but dopamine

cannot

http://en.wikipedia.org/wiki/L-DOPA http://en.wikipedia.org/wiki/Lewy_bodies http://en.wikipedia.org/wiki/Parkinson%2

7s_disease http://en.wikipedia.org/wiki/Alzheimer%2

7s_disease

Thank you for your attention