demyelinating degenerative diseases Flashcards
demylinating diseases are _ conditions that preferentially damage _ with relative presevation of _
the CNS has a limited capacity to regenerate _
acquired conditions
myelin
axons
myelin
Multiple Sclerosis has distinct episodes of neurologic deficits sperated in _ attributable to white matter lesions that are seperated in _
time
space
(there are new, old, and in between lesions that occur in different parts of the brain)
AUTOIMMUNE
in MS there are _ and _ episodes of variable duration
relapsing and remmitting
(neurologic def followed by gradual partial recovery)
the freq of relapses tend to decrease with the longer youve had the disease but there is steady neurologic deterioration**
common signs of MS
inital symptom:
brainstem:
spinal cord:
inital symptom: unilateral visual impairment** (optic neuritis)**
brainstem: ataxia and nystagmus (CN signs)
spinal cord: Motor and sensory impairment of the trunk and limbs with a loss of bladder control
who is more likely to get MS
genetic MS is 15 fold higher in first degree relatives what are the receptor genes and HLA genetic links to MS?
Environmental risk factors:
Inflammation risk factors:
women are more likely
genetic: receptors; IL-2 and IL-17, HLA DR2
Environmental: away from equator, low vitamin D
inflammation: chronic
inflammation causing MS is initiated by _ and _ cells that react against self _ antigens and secrete cytokines.
CD4+/TH1 and TH17 cells
myelin
TH1 cells secrete _ which activated _
IFN gamma which activates macrophages
TH17 cells promote recruitment of _
leukocytes
MS plaques are usually infiltrated by?
T cells (CD4+)
MS has damage to the _ matter (can extend though)
grossly the finding of MS is?
white matter
multiple well circumscribed slightly depressed plaques that is firmer than the surrounding white matter (sclerosis)
where is the pathology in MS located in the brain
ADJACENT TO THE VENTRICLES and optic nerves (optic neuritis)
what is the stain you can do in MS to show the presence or absence of myelin
Luxol Fast Blue stain
- blue= myelin
- pink= no myelin
what cells are present in MS and what is preserved in MS- what stain can you use to see this preservation?
lipid laden macrophages ( as we breakdown myelin lipids are released and macrohpages comes to clean it up)
axons are preserved- can see with a neurofilamtent IHC stain
what is a stain for macrophages we can see in MS with the increase in lipid laden macrophages
on histology of MS you can also see _ cuffing
CD68+ (stain for macrophages-will be increased)
perivascualar cuffing
there are 3 stages to a MS plaque
active, inactive and shadow
active plaque has _ myelin breakdown with abundant _ that contain lipid rich _ positive debris. There is perivascular and inflammatory infiltrate at the _ edge of the plaque. There is relative preservation of _ within the plaque and depletion of _
Inactive plaque is _ and inflmmation _. There is no _, there is a decrease in _ and a slight decrease in _. In this stage there is _ proliferation and gliosis.
Shadow plaque in an in between stage and the white matter is _ sharply circumscribed. There is abnormally thinned out _ sheaths and partial/incomplete _ by the surviving oligodentrocytes
ongoing, macrophages ,PAS, outer, axons, oligodendrocytes
silent, disappears, myelin, oligodetrocyte nuclei, axons, astrocyte
NOT, myelin sheaths, remyelinization
