neuro uworld Flashcards
subacute sclerosing encephalitis of Measles
Measles virus
-helical, envelopped RNA virus, which is a member of the Paramyxoviridae family. Measles manifests with prodromal fever, cough, coryza (runny nose), conjuctivitis and erethematous maculopapular rash.
complications later: Subacute sclerosing encephalitis--> a certain measles virus that is missing an antigen (M protein). The missing antigen causes failure of the meales virus to be cleared by the immune system and allows its persistence in the CNS. -inflammation -demyelination -gliosis -neurons and glial cells display viral nuclear inclusions -progressive but fatal -dementia, neuro defecits
patients that survive an initial subarachnoid hemorrhage more than 50% develop secondary arterial vasopasm
- the vasopspam occurs around the ruptured aneurysn
- cause cerebral ischemia presenting with a new onset confusion, and or focal neur deficit 4-12 after
- it may not show on CT
- transcranial color doppler is needed
prevent: use nimodipine a selective calcium channel blocker
valproate exposed neonates
valproate inhibits intestinal folic acid absorption
neural tube defects =(
Tardive dyskinesia is a possible side effect of antipsychotic use
-involuntary perioral movements:
biting, chewing, grimacing, tongue protrusions. and possible involuntary choreoathetoud movements of head, limbs, trunk
4 months to 4 years after treatment
may be irreversible
transpeptidases =
penicillin-binding proteins
targets for penicillins and cephalosporins
a change in structure of the pbp prevents binding –> resistance
endothelium-dervied relaxing factor EDRF =
NO!
-cholinergic agonists bind to muscarinic receptors on endothelial cells and promote release of NO, NO activates GC –> cGMP –> vasodilation
phenytoin increases expression of PDGF as a side effect
when gingival macrophages are exposed to increased amounts of PDGF, they stimulate proliferation of gingical cells and alveolar bone. –> gingival hyperplasia
first line benzos for alcohol withdrawal?
chlordiazepoxide and diazepam - long acting
first line treatment for patients with advance liver dysfunction benzos?
lorezapam and oxazepam
NF1, neurofibromas are tumors of schwann cells
neurocrest cells
Calcified cystic mass = craniopharyngioma
- suprasellar region
- calcifications visible on neuroimaging
- macroscopic: cystic or partially cystic with solid areas
- LM: lines with sqaumous epithelium, keratin pearls may be seen
- cysts are usally filled with a yellow, viscous fluid that is rich in cholesterol crystals
remnant of rathkes pouch an evagination o the ectoderm that lines the fetal oral cavity this protrusion becomes the anterior pituitary, note the posterior pituitary is formed from the neuroectoderm
rathkes pouch
evagination of ECTODERM that lines the fetal oral cavity. This protrusion eventually becomes the anterior pituitary (adenopyhophysis)
notes the posterior pituitary develops from the NEUROECTODERM
diapragmatic contraction is responsible for most of the intrapeural pressyre fall during inspiration
lets say we have a physiograph and we see decreasing amplitude of the cyclic intrapleural pressure and we compare with a phrenic nerve stimulation graph that is normal, then the decrease is dye to weakening inspiration diaphragmatic contractions due to a pathology at the NMJ! examples include myasthenia gravis, restrictive lung disease or chest wall disease which could cause normal diaphragm to fatigue rapidly.
Pancoast tumor
cancer of apex of lung can affect the superior sympathetic cervical ganglion leading to horners syndrome
-it can also cause an ipsilateral compressive brachial plexopathy
treat narcolepsy
modifinil
-a non-amphetamine stimulant
-
A chronically progressive pre-senile demential with cortical atrophy but no other radiological or laboratory abnomralities permits a clinical diagnosis of Alzheimers which is a diagnosis of exclusion
treat:
Cholinesterase inhibitor: donepezil
Antioxidants: vitamin E
NMDA receptor antagonist -memantine
NMDA receptor
n-methyl-d-aspartate receptor for glutamate
-controls synaptic plasticity and memory function
thiorizadine antipsychotic
retinal deposits –> retinitis pigmentosa
specific antispychotic side effects:
Chlorpromazine - corneal deposits haloperiodol - EPS Ziprasidone- prolongue QT Olanzapine- wt gain -clclozapine - agranulocytosis and seizures
nictonic receptors
vs muscarinic
ligand-gated ion channels that open after binding ACh
- influx of Na and Ca
- Efflux of K
M1 and M3 - IP3 pathway to increase intracellular Ca –> PKC
Md- cAMP second messenger system and when activated decreased cAMP! they are g protein coupled
How does flow travel from the third ventricle to the 4th?
the cerebral aqueduct of sylvius
What should we use to cover the organisms that could cause a neonatal meningitis?
ceftriaxone to get most
but to get that pesky listeria we need to use Ampicillin!!!!
Friedreich ataxia
Autosomal recessive
- chromosome 9 protein frataxin - needed for mitochondria function
1. ascending and descending spinocerebellar tract degeneration –> gait ataxia
2. degeneration of the dorsal columns and dorsal root ganglia cause loss of position and vibration sensation
3. kyposcoliosis and foot abnormalities (pes cavus) are common - heart –> hypertrophic cardiomyopathy and gCHF
- DM in about 10%
MS
reduced saltatory conduction
alzheimers atrophy
temporoparietal lobes and hippocampus
Dopamine agonists preferentially stimulate D2 receptors (inhibit the indirect pathway leading to motion, normal is decreased motion)
ergot compounds: bromocriptine and pergolide
nonergot compounds: -pramipexole and ropinirole
HSV-1 esephalitis
early symptoms: headache and fever
mental status changes, CN defictits, seizures may follow.
-temporal lobe –> aphasia , olfactory hallucinations (olfactory cortex involement) and personality changes due to amygdala damge
histo: eosinophillic intranuclear inclusion (cowdy type A) are present in glial cells and neurons, multinucleated giant cells may also be found.
main side effect of benzodiazepines is daytime drowsiness
- the hangover effect–> impaired judgment, and concentration and assoc ataxia –> risk of falling
- shorter acting benzos are more addictive
- shorter benzos would decrease the risk of day time drowsiness
short benzos:alprazolam, triazolam, oxazepam
medium estazolam, lorazepam, temazepam
long: chlordiazepoxide, chlorazepate, diazepam, flurazepam
long acting will be assoc with daytime drowsiness but less withdrawal
Lesions of the macula cause central scotomas
age related macular degeneration
- macula is the central area of the retina
- degeneration causes distortion(metamorphorphopsia) and even loss of central vision (scotomas)
- dry non excitative - deposition of yellows extracellular material in and beneath the bruch membrane and retinal pigment epithelium
2. wet exudatitve, rapid loss of vision due to bleeding secondary to choroidal neovasculazation
radial head subluxation “nursemaids elbow”
- common injury in children resulting from sudden outward pulling on an extended and pronated arm.
- but could happen to adults too
- the radial head subluxatuon can damage the deep branch of the radial nerve leading to weakness or parylysis of forearm extensors compartment muscles
- the deep branch of the radial nerve does not carry the somatic sensory innervation. The superficial branch is sensory
the deep branch arises near the lateral epicondyle of the humerus , where the humerus articulates with the head of the radiums
solubility of anesthetic in the peripheral tissues negatively affects brain saturation
higher peripheral tissue solubility means more anesthetic is extracted from the arterial blood. this increases the arteriovenous concentration gradient, meaning that more anesthetic must be absorbed to saturate the blood and then the brain!
hyperpyrexia
recall PGE2 leads to an increase in the thermoregulatotey set point in the anterior hypothalamus –> fever
NSAIDS and acetominophen will reduce this
-dont give aspirn to kid
-acetominophen ok
-but in the setting of extreme fever give cold blankets first
myoclonic - brief arrhythmic jerking movements, last < 1 second, usally occur in clusters for a few mins, no loss of consciousness
1st line valproic acid
cholinergic agonists:
- increase GI tract smooth muscle tone to produce nausea, vomiting, abdominal cramps and diarrhea
- decrease heart rate, cardiac conduction and contractility –> bradycardia, partial or complete heart block and hypotension
- decrease BP by stimulation of endothelial NO synthesis
- they increase secretions–> leading to excessive sweating, salivation and lacrimation.
- dyspnea via bronchoconstriction due to increased smooth muscle tone in the tracheobronchial tree
use them for?
Bethanechol - used to stimulate peristalsis in postoperative ileus
Bathanechol - treat non-obstructive urinary retention (atonic bladder)
Carbachol and pilocarpine - decrease IOP in glaucoma
