Sun jul 26 Flashcards
which receptor causes the rewarding effects of nicotine?
The alpha4Beta2 nicotinic receptor in the CNS -leads to release of dopamine
is varenicline a full or partial agonist?
Partial
Varenicline MOA for quitting smoking
Partial agonist at nicotinic receptors- reduces symptoms of withdrawal and attenuates the rewarding effects of nicotine
why is cranially nerve IV susceptible to injury?
it has a long course
what is the function of CN IV?
Innervate the Superior Oblique - eye internally rotates and depresses while adducted
when will the gaze be impmaired in someone with a CN IV injury?
when they look down and towards the nose (up-close reading, walking downstairs)
are most DNA virus’s ds or ss?
DS
which DNA virus is ss?
parvovirus
which ds DNA viruses are enveloped?
- Hepadna (hep B)
- Herpes (VSV, HSV)
- Poxvirus
which ds DNA viruses are naked?
Adenovirus
Papova (HPV)
Polyoma (JC and BK)
S100 is found in which cells?
Cells that derived from the neural crest
what type of tumours will stain positive for HMB45?
Melanomas- HMB45 is a MAB against melanosomes
what type of inflammatory response is erythema multiforme?
cell-mediated - CD8 lymphocytes
which infections is erythema multiforme associated with?
HSV and mycoplasma
how does O2 supplementation lead to oxygen-induced hypercapnia?
Areas with poor ventilation lead to shunting of blood to other areas. When O2 is given, the shunting is reversed and blood is taken away from the areas that have adequate respiration, leading to increased physiologic daed space and V/Q mismatch
what causes a charcot bouchard aneurysm rupture?
chronic hypertension
where are charcot bouchard aneurysms in the brain?
Deep brain structures -basal ganglia, cerebellum, pons, etc.
what is the most common cause of spontaneous lobar hemorage?
Amyloid angiopathy
explain the pathophys of cerebral amyloid angiopathy?
B amyloid deposits in the walls of small and medium sized cerebral arteries, leading to weaking and proness to rupture
Presentation of pancoast tumour
- Horners syndrome
- shoulder pain
- upper limb parasthesias
- arereflix arm weakness (brachial plexus compression)
why does vincristine lead to neurotoxicity and peripheral neuropathy?
It interferes wiht microtubule formation in nerve axons
MOA of vinca alkaloids?
inhibit microtubule polymerization
complications of Sjogrens syndrome?
- corneal damage
- dental carries
- non-hodgkin lymphoma
what should you give to someone who overdose on salicylate (aspirin)?
Na bicarb
how does Na bicarb treat salicylate overdose?
- acts as a base and binds free H in the blood, and converts salicylate to the ionized form - preventing it from moving into tissue
- alkalinizes the urine, increasing the excretion of salicylate
what causes gigantism?
oversecretion of IGF-1 from the liver
what is dofelitide?
a class III antiarythmic
MOA of class III antiarhytmics?
predominantly block the K channels in non pacemaker cells, inhibiting the outward current during phase III and thus prolonging repolarization
which areas are known for chloroquine resistant strains of malaria?
Africa and Asia
If someone aquires malaria from Africa, what should you treat them with?
Atovaquone-proguanil or artemisians (likely chloroquine resistant)
which enzyme of the TCA cycle requires FAD?
Succinate dehydrogenase
What does succinate dehydrogenase do?
Converts succinate to fumarate
which enzyme of the TCA cyle requires GDP?
succinyl-coa synthetase
what does succinyl-coa synthetase do?
converts succinyl-coa to succinate
the conversion of malate to oxaloacete by malate dehydrogenase requires…
NADH
the conversion of oxaloacete to PEP requires…
GTP
how do insulin levels normally change in response to exercise?
they would decrease during exercise - you begin glucose production
what is abruptio placentae?
premature placental separation from the uterus
risk factors for placental abruption?
hypertension, preeclampsia, cocaine or tobacco use, prior abruptio placento, abdomin trauma
presentation of abruptio placentae?
sudden onset vaginal bleeding
- abdominal pain
- high frequency contractions
- tender, firm uterus
what is placenta accreta?
attachment of the placental villi onto the myometrium
how does placenta accreta present?
Usually presents after the delivery of the baby wiht hemorhage and inability to remove the placenta
which tracts degenerate in friederachs ataxia?
- spinocerebellar
- lateral corticospinal
- dorsal columns
- dorsal root ganglia
inheritance of friedreichs ataxia?
autosomal recessive
pathophys of friedreichs ataxia?
Increased GAA repeats due to a mutation in the frataxin gene which codes for a mitochondrial protein involved in the assembly of iron-sulfur enzymes.
Decreased mitochondrial activity leads to increased oxidative stress, and degeneration of the neural tracts and peripheral nerves
what is charcot-marie-tooth disease?
AD disorder with dymelination of the peripheral nerves
how may damage to the lateral prefrontal cortex present?
Difficulties with executive functions -motivation, organization, planning and purposeful action
how may damage to the orbitofrontal cortex present?
personality changes, disinhibition and irritability
how does damage to the subthalamic nucleus present?
contralateral hemiballismus
what is uniparental disomy?
When someone receives two copies of a chromosome (or part of a chromosome) from one parent and none from the other
what are cholesteatomas?
collections of squamous cell debris that form a round, pearly mass behind the tympanic membrane
presentation of cholesteatomas?
Most commonly present as painless otorrhea.
Some produce lytic enzymes which damage the ossicles and lead to conductive hearing loss.
If it grows large enough it may erode the vestibular apparatus leading to vertigo, and can cause facial nerve palsies.
