Neuro - Unreviewed blocks

Question 1

Insufficient clearance of __ amyloid can lead to Alzheimer dementia?

Answer 1

Beta-amyloid

Question 2

The K1 capsular polysaccharide present in E.coli is responsible for it causing this dz?

Answer 2

Neonatal meningitis

Question 3

What type of gene mutation to cause Fragile X?

Answer 3

Hypermethylation of arm of X chromosome -> inactivates FMR1-> impairs neural development.

**often has >2000 copies of CGG repeats

Question 4

Puffer fish toxin MOA?

Answer 4

Binds to Sodium channel preventing action potential

Question 5

Osmotic demyelination (central pontine myelinosis) Pathogenesis? MRI findings?

Px?

Answer 5

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

Question 6

Dantrolene used in tx of Neuromaligmant syndrome works by?

Answer 6

Antagonizing Ryanodine receptors to prevent Ca release

Question 7

What is the function of kinesin proetin?

Answer 7

Microtubule associated ATP powered motor proteins involved in the transport of neurotransmitters vesicles down the axon.

Question 8

Donepizil and Rivastigmine may cause syncope due to?

Answer 8

These are cholineterase inhibitors. Excess acetylcoline -> enhanced PS tone -> bradycardia

Question 9

What are the dividing structures for the ant 2/3 and 1/3 of the tongue?

Answer 9

Behind the foramen cecum and terminal sulcus lies the posterior 1/3 of the tongues.

Question 10

Glioblastoma multiforme is often presents with this symptom?

Answer 10

New onset headache that worsens with bending over.

Question 11

Malignant tumors of the parotid gland often compress and disrupt branches of this nerve?

Answer 11

Facial nerve.

Question 12

Patients with prolonged response to succinylcholine have this?

Answer 12

Pseudocholinerase deficiency (this enzyme rapidly metabolizes succinycholine)

Question 13

In a pure sensory defect on one side of the body, what is the most likely location of the lesion?

Answer 13

Thalamus.
The spinothalmic tract and dorsal columns send input to ventral post. lateral nucleus. And trigeminal pathway sends input to ventral post. medial nucleus.

Question 14

What are considered to be the primary cause of lacunar infarts?

Answer 14

Lipohyalinosis (HTN) & microatheromas (DB)

**often caused by HTN or diabetes

Question 15

The UMN and LMN symptoms in ALS is from the loss neurons in these areas?

Answer 15

UMN - loss of corticospinal tract

LMN - loss of anterior horn

Question 16

The jaw jerk reflex is a pathological nerve reflex present in patients with?

Answer 16

Bilateral UMN lesions (e.g ALS)

**Mediated by CN 5(V3)

Question 17

How do oranophosphates affect synapses?

Answer 17

Acts as acetytocholinerase inhibitors

Question 18

What is the function of Praloxidime?

Answer 18

Cholinesterase reactivating agent -> allows for degradation of excess acteylcholine (treats muscarinic and nicotinic effect of organophosphates)

Question 19

Diabetic CN neuropathy often presents as ?

Answer 19

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)

Question 20

Worsening of opioid intoxication after Naloxone administration is due to?

Answer 20

Short half life of naloxone

Question 21

Development of 1st pharngeal arch is associated with what Nerve?

Answer 21

Trigeminal n -> bones of the face and muscles of mastication

Question 22

Development of 2nd pharyngeal arch is associated with this nerve?

Answer 22

Facial N -> styloid process, lesser horn of hyoid and stapes. And muscles of facial expression.

Question 23

Treacher Collins Syndrome?

Answer 23

Abnormal development of 1st and 2nd pharyngeal arches.

Question 24

What is the principle site for NE production?

Answer 24

Locus ceruleus (located in posterior rostral pons near floor of fourth ventricle)

**controls mood arousal,autonomic function.

Question 25

Which two hormones are derived from POMC (propiomelanocortin)?

Answer 25

MSH and Acth

Question 26

Frontal lobe dysfunction can be determined by this means?

Answer 26

Testing abstractions (asking about similarities between 2 objects)

Question 27

snRPS are important component of?

Answer 27

Spliceosomes (these help remove introns from pre-MRNA during processing in the nucleus).

**Dysfunction (SMN1 mutation) causes spinal muscular atrophy

Question 28

Defective SMN1 (spinal muscular atrophy) results in?

Answer 28

Impaires spliceosome function -> degeneration of ant. horn cells in spinal cord.

Question 29

Botulinium toxin can be used to treat these conditions?

Answer 29

Focal dystonia and other disorders of abnormal muscle contraction (spasms of MS and Parkinson’s, LES sphincter in achlasia) etc

Question 30

Should you use histamines and benzos together?

Answer 30

No. Can case cause significant sedation.

Question 31

Deactylation of histones cause increase/decrease in gene transcription?

Answer 31

Decrease (bind tightly to DNA)

**this is part of the mechanism involved in pathology of Huntington ds. Prevent transcription of functional protein.

Question 32

Patients with trochlear nerve palsy often present with?

Answer 32

Vertical diplopia ( most noticeable when the affected eye looks down)

Question 33

Acute spinal cord injury often leads to?

Answer 33

Flaccid paralysis with decreased or absent reflexes below the level of the compression (spinal shock) -> progresses to spastic sx as shock resolves.

Question 34

Which nerve is at risk of injury during procedures in or near the right atrium?

Answer 34

The phrenic nerve.

Question 35

The obuturator nerve innervates these muscles?

Answer 35

Hip adductors

Question 36

This nerve is at risk in temporal bone fractures?

Answer 36

CN 7

Question 37

Korsakoff ayndrome is associated with damage to?

Answer 37

Anterior and dorsomedial thalamic nuclei -> memory loss (anterograde) & confabulation

Question 38

Vitamin E deficiency closely mimics?

Answer 38

Frienderich Ataxia (ataxia - spinocerebellar, loss of position and vibration sense and loss of deep tendon reflexes - peripheral nerve degeneration.

Question 39

Neuroinvasive west nile virus px as?

Limited px?

Answer 39

Meningitis, encephalitis or asymmetric flaccid paralysis, pts have parkisonian features

Mobilifrom rash with flu like sx.