Neuro 4 Flashcards
HIV patient
infected with yeast that has a thick capsule
initial lung infection that travels to CNS
Cryptococcus neoformans
Nerve length constant
measure of how far along a nerve an electrical impulse can propagate. Low length constant- can’t travel as far
Myelin- increases length constant and decreases time constant
Most common cause of death in patients with TCA overdose
refractory hypotension and cardiac arrythmias. Caused because TCAs inhibit fast sodium channels.
Precocious puberty obstructive hydrocephalus parinaud syndrome (paralysis of upward gaze and convergence)
Pineal germinoma
In what gene are the repeats located in Fragile X syndrome?
FMR1 gene
Most common findings in PCA infarction
contralateral hemianopia (w/macular sparing)
Drugs that induce cyp450 system
barbituates rifampin carbamazepine griseofulvin chronic alcohol consumption
Drugs that inhibit cyp450
isoniazid cimetidine macrolides azoleantigungals grapefruit juice
Arnold Chiari malformation
congenital abnormality of impaired development of posterior fossa. Two types
1: benign and may manifest in adulthood as ataxia and headaches
2: more severe, evident in newborn (difficulty swallowing, dysphonia, stidor, apnea)
Most common cause of bitemporal hemianopsia
Prolactinoma (most common pituitary adenoma)
What birth defects are caused by valproate
Neural tube defects
valproate inhibits intestinal folic acid absorption
Two ways that amyloid plaques develop in Alzheimers disease
- Senile plaques- paranchymal extracellular deposits
2. Amyloid angiopathy- deposits in media and adventitia of cerebral vessels
What type of necrosis occurs in a CNS infarct
Liquefactive necrosis
What vessels are ruptured in a subdural hematoma
cortical bridging veins
What sense does not have a relay nuclei in the thalamus
smell
What sense has relay nuclei in the VPL nucleus
pain and temperature sensation, position and proprioception
What sense has relay nuclei in the lateral geniculate body
vision pathway
What sense has relay nuclei in the Medial geniculate body
auditory
What sense has relay nuclei in the VPM nucleus
taste
How do you measure potency of an inhaled anasthetic
minimal alveolar concentration
Two causes of subarachnoid hemmorrhage
rupture of saccular aneurysm or arteriovenous malformation
What is the most common complication of subarachnoid hemorrhage?
Severe vasospams. usually occurs 4-12 days later
What E.coli virulence factor allows for hematogenous spread?
capsule (K-1 antigen)
Confusion, agitaion, tremor, tachycardia, hypertension, clonus, hyperreflexia, hyperthermia, and diapharesis
Patient who is on SSRIs
Serotonin syndrome
Antidote used in severe cases of serotonin syndrome
Cyproheptadine (anti-histamine wih anti-serotonergic properties)
Mechanism of Guillain-Barre
Bug has a ganglioside like substance in LPS layer
Antibodies formed cross react with myelin
Causes segmental demyelination and endoneural inflammatory infiltrate
Guillian Barre is most stronly associated with which infectious agent
Campylobacter jejuni
Symptoms of Guillian Barre
ascending muscle weakness, paralysis and areflexia
First line of treatment for generalized anxiety disorder
Buspirone
Takes up to two weeks to build up to effectiveness and is not useful on an as needed basis.
When are MAOIs still used for depression?
atypical depression and treatment-resistant depression
Features of atypical depression
mood reactivity (major factor)
leaden fatigue
increased sleep and appetite
Low back pain radiating to one or both legs Saddle anesthesia loss of anocutaneous reflex bladder and bowel dysfunction loss of ankle-jerk reflex plantar felxion weakness of feet
Cauda equina syndrome
damage to S2-S4 nerve roots
Aneurysm in what arteries can effect CNIII?
posterior cerebral and superior cerebellar arteries
Cerebellar neoplasm in a child
Cystic tumor comprised of spindle cells with hair like glial processes and granular eosinophilic bodies
Pilocytic astrocytoma
Involuntary choreiform movements
dementia
behavioral abnormalities
Huntington’s
Where do you lose neurons in Huntington’s
caudate nucleus and putamen
Histologic changes in active MS plaques
- Demyelination with relative preservation of axons
- Accumulation of lipid-laden macrophages
- astrocytosis
- infiltration by lymphocytes and mononuclear cells
Characteristic sites for Friedreich’s ataxia involement
Caused by mutation to “frataxin” which is necessary for normal mitochondrial involvement.
- spinocerebellar tract
- dorsal columns and dorsal root ganglia
- Kyphscoliosis and foot abnormalities
- Hypertrophic cardiomyopathy
- Diabetes mellitus
Neurons containing what neurotransmitter are lost in Huntington’s
GABA
What are the three Dopaminergic systems?
Mesolimbic-mesocortical
- regulated behavior (Schizophrenia)
Nigrostriatal
- coordination of voluntary movements (Parkinsonism)
Tuberoinfundibular
- controls prolactin secretion (Hyperprolactinemia)
What bacterial virulence factor causes toxicity associated in meningitis and meningococcemia?
Lipooligosaccharide
What is the mechanism by which barbituate IV anesthetics wear off?
Redistribution of the drug into tissues
MOA of penicillins and cephalosporins
irreversible binding to penicillin-binding proteins
Major toxicity of lamotrigine
life-threatening hypersensitivity. First manifests as a skin rash.
What antidepressants have a risk of inducing mania
TCAs and venlafaxine
Mechanism of lorazepam?
Allosteric binding to GABA-A receptor, stimulating the influx of chorlide ions causing hyperpolarization.
What three drugs allosterically bind to GABA receptors
Benzos, alcohol, and zolpidem
Functioning by facilitating the inhibitory action of GABA
Structure of the three GABA receptors
GABA-A: ion channel
GABA-B: G-protein coupled receptor
GABA-C: ion channel
