Common Neuro Conditions Flashcards
What is a tau protein?
A usually very soluble protein, encoded by MAPT gene
What is neurofibrillary tangles?
A tangle formed from tau protein
What is a primary brain injury?
An initial insult, processes of physical displacement
What is secondary brain injury?
gradually developing post trauma pathology
What is Alzheimer’s disease?
A cognitive impairment leading to dementia, which deficits with sensation, processing speed, executive functioning, motor skills, perception, language, and memory. It is the most common cause f dementia.
What is the distinct pathological signature emerging in Alzheimer’s disease?
Loss of brain tissue, widening of the patterns in the brain, and cortical tissue loss.
What 5 things creates cortical atrophy?
Loss of parenchyma, enlargement of ventricles in the brain, narrow gyni - bigger gaps in the brain, widened sluci - bigger gaps in the brain, and atrophy of para hippocampal cortex.
What are Alzheimer disease ultrastructural features?
Amyloid plaques/senile plaques and neurofibrillary tangles.
What are amyloid/senile plaques?
The plaques are extracellular deposits of beta amyloid which accumulates in the brain tissue. The recruitment of activated astrocytes and microglia creates an inflammatory response. The plaques are not well correlated with clinical signs, they are made from an amyloid precursor protein, and the beat amyloid is secreted from neurons into fibrils, which makes up the amyloid plaques that sit in the brain tissue.
Explain how neurofibrillary tangles are made.
They are formed from tau proteins, and the tau becomes insoluble when it is highly phosphorylated, Hyperphosphorylated tau is insoluble, and it accumulates in the cytoplasm and the fire filaments are observable, known as neurofibrillary tangles.
What is the amyloid cascade hypothesis?
Step 1 is amyloid accumulation and may be the initial step in AD pathogenesis, and step 2 leads to deposition of tau protein, step 3 is taupathy is linked to neuronal decline and synaptic loss, and step 4 is that this in turn results in classical cognitive decline.
What is the amyloid cascade hypothesis?
Step 1 is amyloid accumulation and may be the initial step in AD pathogenesis, and step 2 leads to deposition of tau protein, step 3 is taupathy is linked to neuronal decline and synaptic loss, and step 4 is that this in turn results in classical cognitive decline.
What is beta amyloid seeding?
Prion like seeding of uninfected brain tissue. APP gene variants are exclusively genetic forms of AD, variants that increase the amyloid beta production or its ability to create plaques sufficed to induce AD pathology progression, or rare variant reduced amyloid beta production protects against AD pathology.
What is a tau protein?
It is a usually very soluble protein encoded by MAPT gene, the cell makes a lot of tau protein and it is widely distributed, MAPT is microtubule associated protein tau. It stabilises microtubule network in axons, it is abundant in neurons of CNS, the microtubules are important for axonal transport, and is involved in the movement of transport vesicles and important molecules.
Explain the role of inflammation in Alzheimer’s Disease.
The microglial cell activates amyloid deposition. The activated microglial/astrocytes prominent feature in AD pathology. Genetic linkage with regulators of microglial function, Felsky et al 2019 reports a correlation between activated microglia in AD pathology.
