Neuro - Unreviewed blocks Flashcards
Insufficient clearance of __ amyloid can lead to Alzheimer dementia?
Beta-amyloid
The K1 capsular polysaccharide present in E.coli is responsible for it causing this dz?
Neonatal meningitis
What type of gene mutation to cause Fragile X?
Hypermethylation of arm of X chromosome -> inactivates FMR1-> impairs neural development.
**often has >2000 copies of CGG repeats
Puffer fish toxin MOA?
Binds to Sodium channel preventing action potential
Osmotic demyelination (central pontine myelinosis) Pathogenesis? MRI findings?
Px?
Rapid correction of chronic hyponatremia (often found in alcoholics). MRI will show; focal, symmetric demyelination of the pons.
Pseudobulbar palsy (dysarthria, dysphagia, dysphonia)
Quadriparesis.
Others: locked-in sx
Dantrolene used in tx of Neuromaligmant syndrome works by?
Antagonizing Ryanodine receptors to prevent Ca release
What is the function of kinesin proetin?
Microtubule associated ATP powered motor proteins involved in the transport of neurotransmitters vesicles down the axon.
Donepizil and Rivastigmine may cause syncope due to?
These are cholineterase inhibitors. Excess acetylcoline -> enhanced PS tone -> bradycardia
What are the dividing structures for the ant 2/3 and 1/3 of the tongue?
Behind the foramen cecum and terminal sulcus lies the posterior 1/3 of the tongues.
Glioblastoma multiforme is often presents with this symptom?
New onset headache that worsens with bending over.
Malignant tumors of the parotid gland often compress and disrupt branches of this nerve?
Facial nerve.
Patients with prolonged response to succinylcholine have this?
Pseudocholinerase deficiency (this enzyme rapidly metabolizes succinycholine)
In a pure sensory defect on one side of the body, what is the most likely location of the lesion?
Thalamus.
The spinothalmic tract and dorsal columns send input to ventral post. lateral nucleus. And trigeminal pathway sends input to ventral post. medial nucleus.
What are considered to be the primary cause of lacunar infarts?
Lipohyalinosis (HTN) & microatheromas (DB)
**often caused by HTN or diabetes
The UMN and LMN symptoms in ALS is from the loss neurons in these areas?
UMN - loss of corticospinal tract
LMN - loss of anterior horn
The jaw jerk reflex is a pathological nerve reflex present in patients with?
Bilateral UMN lesions (e.g ALS)
**Mediated by CN 5(V3)
How do oranophosphates affect synapses?
Acts as acetytocholinerase inhibitors
What is the function of Praloxidime?
Cholinesterase reactivating agent -> allows for degradation of excess acteylcholine (treats muscarinic and nicotinic effect of organophosphates)
Diabetic CN neuropathy often presents as ?
Acute onset diplopia (down and out) with normal light and accommodation reflex (spares peripheral fibers).
Compare this to compression of CN III (motor and PS functions affected)
Worsening of opioid intoxication after Naloxone administration is due to?
Short half life of naloxone
Development of 1st pharngeal arch is associated with what Nerve?
Trigeminal n -> bones of the face and muscles of mastication
Development of 2nd pharyngeal arch is associated with this nerve?
Facial N -> styloid process, lesser horn of hyoid and stapes. And muscles of facial expression.
Treacher Collins Syndrome?
Abnormal development of 1st and 2nd pharyngeal arches.
What is the principle site for NE production?
Locus ceruleus (located in posterior rostral pons near floor of fourth ventricle)
**controls mood arousal,autonomic function.
