Dementias and Stroke Flashcards
a descriptive term for a collection of
symptoms that can be caused by a number of
disorders that affect the brain
Dementias
how is dementia diagnosed
Dementia is diagnosed only if two or more brain
functions - memory, language skills, perception, or
cognitive skills (reasoning and judgment) - are
significantly impaired without loss of consciousness.
Memory loss is a common symptom, but memory
loss by itself does not indicate dementia (T/F)
True
a progressive neurodegenerative
disorder in which decline of general cognitive
function occurs, usually accompanied by
affective and behavioral disturbances.
AD
cause for dementia
Some cases have a familial (genetic) basis,
but the great majority (90%) appear to be
sporadic
patients with AD live for ______
years after they are diagnosed. Patients with
AD often die of _____ _____ because
they lose the ability to swallow late in the
course of the disease.
8 to 10
aspiration pneumonia
The key neuropathological elements of AD (macroscopic)
gross atrophy of the
brain
The key neuropathological elements of AD (microscopic)
amyloid plaques, neurofibrillary tangles extensive neuronal loss in the neocortex, hippocampus, and other subcortical regions of the brain.
accumulations of aggregated molecules in the extracellular
space of the brain
Amyloid plaques
The principal proteinaceous component of plaques is the
amyliod-beta peptide
A-beta
amyliod-beta peptide
A beta
a 38– to 43–amino acid peptide derived from a much larger protein, the
amyloid precursor protein, APP
tends to spontaneously self-aggregate into multiple coexisting physical forms
alpha beta
A-beta peptide is produced from much larger transmembrane protein, the amyloid precursor
protein, ____. The exact physiological function of
APP is unknown.
APP
The toxic A peptide is produced from the transmembrane protein APP via cleavage by two enzymes:
beta-secretase and gamma-secretase
Excess production of A is a key initiator of cellular damage in ___
AD
______ tangles are found in the cytoplasm of neurons
Neurofibrillary tangles (NFTs)
The NFTs (Neurofibrillary tangles) are composed of highly stable polymers of cytoplasmic proteins called
TAU
proteins possess microtubule-binding domains and help to stabilize
microtubules.
TAU
•In AD, tau proteins become highly phosphorylated and as a result, dissociate
from ________ and polymerize into filaments forming NFTs.
•The microtubules disintegrate in the process, leading to disruption of
______- transport and subsequent neuronal death.
microtubules
axoplasmic
Genetics of AD occur in mutations of chromosomes :
mutations on
chromosomes 21, 14, and 1.
Mutations on chromosome 21
cause the formation of abnormal
____ ____ _______
amyloid precursor protein (APP).
Mutations on chromosome \_\_\_ and \_\_ cause formation of abnormal presenilin proteins (prenesilin proteins are structural subunits of gamma-secretase complex)
14
1
In about 50% of late-onset AD (60 and older) patients, __ isoform of ____
has been identified as a risk factor
E4
apoE4
there three major isoforms ___, ___, ___, which arise from
different alleles __, ___, ___ of a single gene on chromosome 19.
(apoE2, apoE3, and apoE4)
E2, E3, and E4
The ___ allele is associated with increased risk and earlier onset of late-onset AD,
inheritance of __ allele is associated with decreased risk and later onset
E4
E2
Treatment of AD (what 2 drugs)
-Cholinesterase inhibitors
-Memantine-NMDA receptors
modulator
The second most common type of dementia
May appear soon after a single major stroke that
disrupts the blood supply to a significant portion of
the brain (“post-stroke dementia”)
vascular dementia
symptoms of vascular dementia
vary depending on the affected brain
areas:
-with sudden decline function, rather than the slow, steady decline
underlying causes of vascular dementia
hypertension, diabetes, smoking, or
lack of exercise
characterized by the sudden onset of a focal
neurologic deficit due to an abnormality of the cerebral circulation, such as
blockage or rupture of the blood vessel, supplying the brain.
-third leading cause of death in the United States
Stroke
•Significant risk factors of stroke (6)
hypertension hypercholesterolemia diabetes smoking heavy alcohol consumption oral contraceptive use
Strokes may be classified into two major categories based on
pathogenesis:
ischemic stroke and hemorrhagic stroke
•In ______ stroke, vascular occlusion interrupts blood flow to a specific
brain region, producing a fairly characteristic pattern of neurologic
deficits
ischemic
Thrombus may form in an artery that is already very narrow. If it
completely blocks the artery, it is called
thrombotic stroke
Thrombus may break off from another place in the blood vessels of the
brain, or some other part of the body, and travel up to the brain to block a
smaller artery. It causes
embolic stroke
______ stoke occurs upon rapture of a weakened blood vessel in the brain. pattern of deficit depends on the location of the bleeding
•Hemorrhagic strokes
Drugs use to treat ischemic strokes (3)
- Thrombolytic agents
- Anticoagulants
- Aspirin
these agent must be administered in the hyperacute phase of stroke (<4.5 hours after
onset).
Thrombolytic agents
_____ reduces the risk of serious vascular events in high-risk patients (e.g., those
with previous myocardial infarction) by 20-25%.
Aspirin
•Low-dose (<100 mg/day) aspirin, is relatively (but not exclusively) selective for _____,
and is associated with a lower risk for GI adverse events
COX-1
aspirin approximately doubles the mean bleeding time in healthy person for 4-7 days.
This effect is due to irreversible acetylation of platelet ____
COX
Hemorrhagic stroke treatment
Treatment usually involves
attempting to control high
blood pressure, bleeding, and
brain swelling.
Thrombolytics are not given to someone who is having a \_\_\_\_\_ stroke. They could worsen the stroke by causing increased bleeding.
hemorrhagic
these drugs were withdrawn from the
market to cardiovascular toxicity
•COX-2 selective inhibitors
currently is the only COX-2 inhibitor
licensed for use in the U.S.
Celecoxib
CELEBREX
_____ ____related to drug use promotes
damage of cerebral arterioles, which may eventually
rupture, resulting in stroke
•Acute hypertension
amphetamines, over the
counter sympathomimetics (acute hypertension drugs) increase ______
release
catecholamine
may cause spontaneous subclinical
hemorrhages that eventually become clinically
significant through their anti-platelet effects (4)
Thrombolytic agents
aspirin
anticoagulants
SSRI
can induce acute hypertension and increase the risk of stroke (3)
Caffeine
cigarette smoking
alcohol abuse
