Neuro Flashcards
1
Q
Blind as a bat, mad as a hatter, red as a beet, hot as a hare, dry as a bone, the bowel and bladder lose their and the heart runs alone.
What kind of poisoning does this describe and how do you counteract it?
A
Atropine poisoning (competitive agonist of muscaric receptors–counters ‘rest and digest’)-similar type symptoms can occur when cutting down trees, b/c atropine comes from plant (Jimmy Weed).
Physostigmine-a reversible cholinesterase inhibitor.
2
Q
ACh release from presynaptic terminal vesicles at the NMJ depends upon influx of extracellular ____________ at the presynaptic terminal?
A
Calcium. Influx of Ca2+ in the nerve terminal happens after neuronal depolarization and opening of VOLTAGE-GATED calcium channels.
3
Q
Inability to form the membrane attack complex (C6-C9) will have recurring infections of what bacteria?
A
Neisseria species. (meningitis–high fever, chills, PETECHIAL SKIN RASH affected PALMS AND SOLES.
Treatment: IV Ceftriaxone for 2 weeks.
4
Q
How does neisseria (meningococcal) enter into the body and infect?
A
Pili are responsible for epithelial attachment to the nasopharynx.
5
Q
What branch of trigimenal nerve leaves the skull via the foramen ovale?
Foramen rotundum?
A
Foramen ovale: V3, mandibular (muscles of mastication–>masster, medial and lateral pterygoids, and the temporal is).
Formane rotundum: V2, maxillary
6
Q
What are the most common causes of aseptic meningitis?
A
Aseptic–>non-bacterial
MCC of aseptic meningitis are enteroviruses (coxsackie, echo, polioviruses)
Enteroviruses are so named because they go through the fecal-oral route of entry.
7
Q
Calcified cystic tumors in the head.
Cysts are filled with yellow, viscious fluids with cholesterol crystals. Keratin pearls may be seen.
A
Craniopharyngiomas–>come from Rathke’s pouch, just like the anterior pituitary does!
Cause headaches, growth problems and bitemporal hemianopia.
8
Q
Patient faints when you put a speculum in their external auditory meatus. What nerve is causing this problem?
A
Vagus Nerve (X)–>This is vasovagal syncope.
Stimulate the vagus nerve and you stimulate parasympathetics (decreased HR and blood pressure).
Note: This would only occur due to stimulation of the POSTERIOR WALL, b/c most of the sensation of the canal is from CN V3 (mandibular branch of trigeminal).
9
Q
Baby with blue eyes, fair skin, mousy odor.
What is the problem?
What enzyme is deficiency?
What do you need to supplement the diet with?
A
PKU:
Can’t do this–>
Phenylalanine to Tyrosine via Phenylalanine hydroxylase.
Don’t have PHENYLALANINE HYDROXYLASE.
Give these patients TYROSINE in their diet, and don’t give them PHENYLALANINE! The increased phenylalanine is what causes the neuro problems.
10
Q
What enzyme deficiency will cause a build up of methlmalonyl CoA?
A
Methylmalonyl CoA ISOMERASE, which catalyzes the following reaction:
Methylmalonyl CoA—->Succinyl CoA (which can then enter the TCA cycle).
note: Methylmalonyl CoA occurs when there is catabolism of isoleucine, valine, threonin, methionine, cholesterole and odd-chain FA.
11
Q
What does Waterhouse-Friderichsen syndrome refer to?
A
Meningococcal (Neisseria) sepsis that causes hemorrhagic destruction of the bilateral adrenal glands.
12
Q
How do you determine the following on the mental status exam:
Orientation Comprehension Concentration Short-term memory Long-term memory Language Visual Spatial
A
Orientation: Providing name, location, and current date.
Comprehension: Following multistep commands
Concentration: Reciting months of the year backwards
STM: Recall three unrelated words after 5 minutes.
LTM: Providing details of significant life events.
Language: Writing a sensible sentence containing a non and a verb.
Visual spatial: Drawing a clock face.
13
Q
What causes the neurologic pathology in Neimann Pck?
A
Sphingomyelinase deficiency-causes accumulations of the ceramde phospholipid sphingomyelin.
14
Q
Characteristic changes of a neuron that include: shrinkage of cell body, EOSINOPHILIA of the cytoplasm, pyknosis of the nucleus and loss of Nissl substance (ribosomes).
A
Red neuron: irreversibly damaged neuron looks like this between 12-24 hours after insult.
15
Q
Enlargement of hte cell body, eccentric nucleus, enlargement of the nucleolus, dispersion of nissl substance.
A
Loss of axon reaction.
16
Q
How do you prevent a neonate from getting tetanus?
A
Make sure mom is immunized because she will pass IgG through the placenta and provide passive immunity to the neonate until he/she gets vaccine at 2 months of age.
17
Q
Drug that makes you hostile, belligerent and possibly homicidal.
A
PCP (Phencyclidine)
18
Q
Occlusion of what artery leads to: contralateral homonymous hemianopia with macular sparing?
A
Posterior cerebral artery:
Causes ischemic injury to the ipsilateral striate cortex.
19
Q
If a person has a stroke in an area that causes completely loss of sensation on the contralateral side, where is the damage?
A
Thalamus: The VPL and VMP nuclei are damaged.
20
Q
Lacunar infarcts are the result of small vessel lipohyalinosis and atherosclerosis involving penetrating vessels supplying the deep brain structures. What are risk factors for lacunar infarcts?
A
DM and uncontrolled hypertension.
21
Q
Neurofibrillary tangles are seen in ________
A
alzheimers…along with amyloid plaques.
22
Q
The only serotonin-releasing neurons in the CNS are found in the ___________ nuclei
A
Raphe…These neurons disseminate widely to synapse on numerous structures in the CNS.
23
Q
Recurrent lobar hemorrhages in an elderly patient most likely result from ________ ________________ ____________.
A
Cerebral amyloid angiopathy.
This is where B-amyloid is deposited int he arterial wall, resulting ina weak wall and predisposition to rupture. It is associated iwth advanced age and not related to systemic amyloidosis. RECURRENT HEMORRHAGIC STROKE is the most common presentation of cerebral amyloid angioapathy. Unlike cerebral hemorrahges from hypertension, amyloid-associated strokes are less severe. They are usually in the cerebral hemispheres (LOBAR STROKES) and involve smaller areas of brain parenchyma.
24
Q
Gram + coagulase negative staphylococcus can cause meningitis. What is the most important virulence factor this organism can have?
A
Staph. epidermidis: BIOFILMS
25
What else will you see with the following symptoms:
1. Kyphoscoliosis
2. Pes Cavus (high instep)
3. Lower extremity ataxia
Hypertrophic Cardiomyopathy
This is Friederch ataxia, an autosomal recessive condition where the posterior columns of the spinocerebellar tracts of the spinal cord show degeneration. Children ages 5-15.
26
The number of NEW cases of a disease per year divided by the total population at risk.
Incidence.
27
The number of persons with a disease/total population at a SPECIFIC POINT IN TIME.
Prevalence
28
Morphine is an analgesic which can be injected into the epidural space for long-lasting analgesia. How does morphine help terminate pain at the spinal level?
When morphine binds mu receptors, it causes G-protein coupled activation of potassium channels to INCREASE POTASSIUM EFFLUX. This leads to HYPERPOLARIZATION OF post synaptic neurons and termination of pain transmission.
29
Hydrocephalus (enlargement of ventricles, intracranial calcifications, and CHORIORETINITIS form the class triad of ___________________ in neonates.
Congenital toxoplasmosis-acqured in urtero via the placenta.
Expecting mothers, avoid cat feces.
30
Viral meningitis is typically caused by what type of viruses?
Enteroviruses (fecal-oral)
Like: Coxsackie, Echo and Polio
31
Chronic thiamine (B1) deficiency leads to the diminished ability of cerebral cells to utilize glucose. The mechanism is decreased function of the enzymes that use vitamin B1 cofactor (pyruvate dehydrogenase, alpha=detoglutarate, and one other one). How do you diagnose thiamine deficiency?
Erythrocyte transketolase activity. (which the third enzyme it is a cofactor for).
Note: An increase in erythrocyte trasnketolase levels after thiamine infusion is diagnostic for thiamine deficiency.
32
Acute hypoxic and/or complete ischemic injury in most organs results in coagulative necrosis of hte parenchymal cells. However, kn the brain, such injury produces a focal of ________________ necrosis that occurs within 10 days of the infarction.
Liquefactive...
Eventually, the infarcted CNS tissue is replaced with a cystic astroglial scar.
Note: Fibrinoid necrosis - vasculitidies
Caseous necrosis = tb
Non-enzymatic fat necrosis = local trauma to adipose tissue
33
Congenital abnormality associated with the anti-epileptic valproate.
Meningocele: Valproate inhibits intestinal folic acid absorption.
34
What never is damaged:
Right leg numbness. Lifts right foot high than left when walking, and right foot slaps to the ground with each step. Unable to EVERT the right foot.
Common peroneal: most injured nerve in the leg. Starts in popliteal fossa and then courses laterally into the antior compartment of the leg, passing superfically around the head and neck of fibula.
Lesion causes plantarflexed and inverted goo!
35
How does KETAMINE block OPIOID tolerance?
Morphine tolerance is thought to come from glutamate binding to NMDA receptors, activing them. Ketamine is an NMDA receptor blocker, which will keep glutamate off of that shit.
36
The NF-1 autosomal dominant or recessive?
DOMINANT, with high penetrance.
YOu get: cafe'-au-lait spots, neurofibromas, optic nerve gliomas (lisch nodues are pigmed hamartomas of the irus and are asymptomatic.
37
Hypothalamic nucleus responsible for circadian rhythem
Suprachiastmatic
38
Hypothalamic nuclei responsible for satiety.
Ventro medial: lesion here leads to growing ventrally and medially)!
Note: This nuclei is stimulated by leptin, so leptin = satiety.
39
Lateral hypothalamic nuclei is response of _________.
Hunger: lesion leads to anorexia.
Lateral nuclei is INHIBITED by leptin. leptin inhibits hunger.
40
Anterior nuclei of hypothalamus mediates __________
head dissipation via parasympathetics.
Anterior turns on the A/C.
Destruction leads to hypothermia.
41
What part of the hypothalamus is responsible for secreting dopamine (thus inhibiting prolactin) and also secreting GHRH and GnRH?
Arcuate nuclei
42
Part of hypothalamus that releases ADH, Corticotropin-releasing hormone, oxytocin and thyrotropin-releasing hormone secretion.
Paraventricular
43
What does the supraoptic nuclei of the hypothalamus secrete?
ADH and Oxytocin: Sends it down to the posterior pituiary
44
What will the glucose, WBC, and protein levels be like for viral vs bacterial meningitis?
Bacterial:
Low Glucose
High Protein
High WBC with neutrophil predominance
Viral:
Normal
Protein slightly elevated
WBC count: Lymphocytic predominance
45
What is the most common cause of bacterial meningitis in adults of all ages?
What does it look like on microscopy?
Strep pneumo: Gram + cocci in pairs, lancet-shaped.
Strep pneumo is the leading cause of community-acquried pneumonia, otitis media, and meningitis in adults. S. pneuoniae appears on gram stain as lancet-shaped, gram+ cocci in pairs.
46
Bean-shaped gram - cocci in pairs
Neisseria meningitits: occurs in army barracks, college dorms, etc.
47
Mechanism of lorazapam.
Benzos, barbituates and alcohol all three bind to the different components of the GABA1 receptor and facilitate the inhibitory action of GABA in the CNS.
Specifically, benzos bind GABAa and stimulate the influx of choloride ions into the neurons. It INCREASES THE FREQUENCY OF THE ION CHANNEL OPENING.
48
What vitamin is an essential cofactor for transamination and decarboxylation of amino acids in gluconeogenesis and for other essential biochemical processes...
Pyridoxine (Vitamin B6)
Transamination reactions typically occur between an amino acid and an alpha-keto acid. The amino group is transferred tot he alpha keto acid from the amino acid and the alpha-keto acid thereby becomes an a.m.
49
Deficiency of folate or vitamin B12 results in _____________ anemia
Megalosblastic
Folic acid is an essential cofactor in nucleic acid synthesis.
50
WHat amino acids will go from:
Proprionic acid --->Methylmalonyl CoA--->Succinyl CoA--->into the TCA cycle?
Threonine
Methioniene
Valine
Isoleucine
These are odd-chain that are converted to methylmalonic acid by biotin-dependent carboyxlation.
A congenital deficinecy of propioinyl CoA carboxylase prohibits propionyl CoA from turning into Methylmalonyl CoA, so you get proprionic acidemia as propionyl CoA accumulates.
Proprionic acidemia: poor feeding, vomiting, hyponia, lethargy, dehydration, and anion gap acidosis.
51
Cocaine intoxication causes agitation, dramatic symmetric pupillary dilation that remains responsive to light, tachycardia and blood pressure elevation. How is cocaine similar to Tri-cyclic antidepressants?
They both inhibit norepininephrine, serotonin and dopamine reuptake.
52
Double vision when looking down would be caused by a problem with what nerve?
Trochlear
53
disease that causes loss of anterior horn (LMN lesion) and degeneration and atrophy of the lateral corticospinal tracts (UMN lesions)
Amyotrophic lateral sclerosis
54
Associated with HYPERTROPHIC CARDIOMYOPATHY, foot abnormalities, kyphoscoliosis, and DM
Friedrich ataxia: autosomal recessive disorder that manifests in children 5-15 yeras old.
55
What kind of problems in the spinal cord does a vitamin B12 deficiency cause?
Subacute combined degeneration of the dorsal (posterior) and lateral spinal columns.
56
What happens after you have irreversible damage to a neuron? (Meaning, how is the damage "repaired"?)
It's not repaired, but gliosis does occur in the area resulting in glial hyperplasia.
57
What drug can be used to treat bipolar disorder in an individual who also has tonic-clonic seizures?
Valproic acid
Note: Carbamazepine is also a mood stabilizing agent used to treat bipolar and seizures...but it would be first line from simple partial and complex partial seizures.
58
What type of drug is sertraline?
SSRI
Used to treat major depression, OCD, and panic disorder
59
How would you treat crytocococcal meningitis (HIV patient) as demonstrated by India ink staining of cerebrospinal fluid?
Amphotericin B and flycytosine.
Binds ergosterol in fungi and causes pores.
60
What is an antitubercular drug that inhibits mycolic acid synthesis?
Isoniazid.
61
Acyclovir is used to treat:
HSV meningitis, which is diagnosed ousing PCR.
62
You have an alcoholic who is in hospital going through withdrawals. You know that you need to give benzo to treat withdrawal.
Normally, you will give long-acting benzos (chlordiazepoxide, diazepam) as first-line meds. When would you need to give short-acting (lorazepam, oxazepam)?
When a person has advanced liver disfunction
63
How do timolol and other non-selective b-blockers treat glaucoma?
diminishing the secretion of aqueous humor by the ciliary epithelium.
Note: Acetalzolamine (a carbonic anhydrase inhibitor that works in the proximal tubule) also decreases aqueous humor secretion by the ciliary epithelium.
64
What is the afferent vs efferent limb of hte light reflex pathway?
Afferent: Optic nerve
Efferent: parasympathetic fibers of the oculomotor nerve.
Note: When optic nerve is damaged, light in that eye will cause neither pupil to constrict (the nerve doesn't sense the light). However, light in the contralateral eye will cause both pupils to constrict (because motor pathways are intact).
65
All sensory pathways except __________ have relay in the nucleus/
Olfaction.
VPL receives impulses from spinothalamic (pain and temp) and medial lemniscus (position and proprioception).
VPM receives inputs from the trigeminal and gustatory (taste) pathways.
Lateral geniculate body acts as relay for the vision pathway. (Receives impulses from the optic nerve and transmits them via the optic radiations to the visual cortex (calcarine sulcus).
Medial geniculate body is part of the auditory pathway. It receives impulses form the superior olivary nucleus and the inferior colliculus of the pons, and projects them to the auditory cortex of the temporal lobe.
66
All three prokaryotic DNA polymerases have proof reading activity and remove mismatched nucleotides via 3' to 5' exonuclease. Which one has 5' to 3' exonuclease activity which is used to excise and replace RNA primers and damaged DNA sequences.
DNA pol 1
67
Guillane-Barre syndrome is strongly associated with _________________ infection
Campylobacter jejuni (causes mild respiratory infection).
G-B is acute demyelinating disease with immune-mediated pathogenesis.
Demyelination is accompanied by "endoneural inflammatory infiltrate" consisting of lymphocytes and macrophages.
68
What does this suggest:
Fixed segmental loss of upper extremity pain and temperature sensation, UE lower motor neuron signs and/or LE upper motor neuron signs in the setting of SCOLIOSIS suggests
Syringomyelia: central cystic dilation in the cervial spinal cord, damages the ventral white commissure (pain and term) and anterior (LMN) horns. (C8-T1)
69
What drug would you give to reverse atropine toxicity and why?
Physostigmine-It is an anticholinesterase agent that can get into the CNS, reversing both CNS and peripheral symptoms of atropine toxicity.
Neostigmine and edrophonium have quaternary ammonioum structure that limits CNS penetration.
Remember that these drugs are to treat myasthenia gravis.
70
Alzheimers:
Prevailing clinical symptoms: slow, progressive memory loss.
Macroscopic brain appearance: mild-to-moderate generalized brain atrophy.
Microscopic changes: neurofib tangles, senile plaques, amyloid angiopathy.
Biochemical abnormalities: ????
Decreased ACh levels in the HIPPOCAMPUS and the NUCLEUS BASALIS OF MEYNERT.
71
What is a big reason why paraneoplastic syndromes cause damage and degeneration of healthy organs and tissues?
The tumor secretes substances that frequently induce an AUTOIMMUNE REACTION that causes the degeneration.
Example: Paraneoplastic cerebellar degeneration. usually caused by anti-Yo (ovary and breast), anti P/Q (lung), and anti-Hu (lung).
72
What virus can cause a recurring painful genital rash after being latent in the sacral
sensory ganglia?
DS DNA viruses
HSV-type 2.
Note HSV-1: usually ABOVE the waist-->typically latent in trigeminal ganglia.
VZV: chicken pox--->latent--->shingles
73
Term used to describe the degeneration of dorsal spinal columns and nerve roots in patients with tertiary syphilis.
Tabes dorsalis
74
Psammoma bodies and swirly's on microscopy. Mostly women have this type of CNS tumor:
Meningioma-->benign tumor of arachnoid cells. Can cause personality changes.
75
How do you treat Maple Syrup Urine Disease (MSUD)?
Defective breakdown of branched chain A.AL (leucine, isoleucine and valine). Need alpha-ketoacid dehydrogenase is the enzyme needed to effectively metabolize these branched chained a.a.
Need as coenzymes: Tender Loving Care for Nancy
Thiamine pyrophosphate, Lipoate, Coenzyme A, FAD, NAD
Note: Some patients with MSUD require high-dose THIAMINE treatment.
76
What pathway connects the hypothalamus to the pituitary
Tuberofundibular pathway (this pathway is responsbile for dopamine-dependent prolactin tonic inhibition).
77
They three impt dopaminergic pathways are:
1. Mesolimbic-mesocortical
2. Nigrostriatal
3. Tuberoinfundibular
What pathologies are associated with each pathway?
1. Mesolimbic-mesocortical: Schizophrenia
2. Nigrostriatal: Parkinsonism
3. Tuberinfundibular: Hyperprolactinemia
78
Abdominal pain, neuropsychiatric manifestations and color change in urine upon standing are classical presenting features of _____________________.
Acute intermittent porphyria (AIP).
This is a problem with the enzyme prophobilinogen deaminase in the heme synthesis pathway, which causes buildup of porphobilinogen and ALA, which are both toxic.
P. 358 in FA
79
Short or long acting benzo:
Alprazolam
Triazolam
Oxazepam
Short (high risk of physical dependence but less daytime drowsiness and risk of falls).
80
Short of long acting benzo:
Chlordiazepoxide
Clorazepate
Diazepam
Flurazepam
Long-acting.
More severe daytime drowsiness, slower clearance and less withdrawal.
81
Short or long acting benzo: Estazolam, Lorazepam, Temazepam
Medium, SUCKA!
82
Opethalmoplegia, ataxia and confusion form the triad of Wernicke Syndrome. Most of these symptoms resolve after thiamine administration. Korsakoff syndrome is a complication of Wernicke encephalopathy. What are the hallmarks of Korsakoff?
Permanent memory loss and confabulation
83
First branchial arch is associated with the ________ nerve.
What structures are associated with it, as well?
CN V (Trigimenal)
Neural crest cells from the first arch form the associated bones: maxilla, zygoma, mandible, vomen, palantine, incus and malleus. Mesodermnal derivatives include all muscles of mastication, anterior belly of digastric, mylohyoid, tensor tympani and tensor veli palatine.
84
What branchial arch?
Styloid process, lesser horn of the hyoid, the stapes are all neural derivatives of the ______ pharyngeal arch?
2nd. Associated with CN II and gives rise to the muscles of facial expression, the stylohyoid, stapedium and posterior belly of digastric.
85
What does low minimal alveolar concentration mean as it relates to anesthetic potency?
The less the MAC, the more potent the drug.
86
Does high solubility of an anesthetic translate to a slow or fast onset of action?
High solubility = slower onset of action.
87
Does a higher arteriovenous concentration gradient translate into a fast or slow onset of action of anesthetics?
Greater the gradient the slower the onset of action.
88
Penicillins and cephalosporins function by irreversibly binding to penicillin-binding proteins such as TRANSPEPTIDASES (which function to cross-link peptidoglycan in the bacterial cell wall).
How might resistance to cephalosporin occur?
A change in structure of penicillin-bindning proteins.
89
Name that headache:
```
Male > female
No family history
Onset during sleep
Behind one eye
Excruciating, sharp and steady
Duration: 15-90 minutes
Associated symptoms: sweating, facial flushing, nasal congestion, lacrimation, and pupillary changes
```
Cluster headache.
90
18 yo college freshman is brought to the ER with a high fever, confusion and headaches. PE reveals nuchal rigidity and purpuric rash on his lower extremities. This infection could have been prevented with a vaccine against one of this bacteria's virulence toxins. What is it?
Capsular polysaccharide.
The N. meningitides vaccine contains immunogenic capsular polysaccharides from from major serotypes of N. meningitidis.
Note: Other virulence factors include LPS endo toxin, pills to attach to resp. mucosa, IgA protease.
91
A 4 year old Asian boy is brought to your office by his mom b/c of facial hair growth. PE reveals enlarged genitalia, pubic hair growth and impaired upward gaze. What is going on?
Hormone secreting brain tumor-->germinoma of the pineal gland. These cause:
1. Precocious puberty: due to B-hCG production
2. Parinaud syndrome: paralysis of upward gaze and convergence, these symptoms occur due to compression of the tectal area of the midbrain.
92
Vitamin E deficiency can occur in individuals suffering from fat malabsorption or abetalipotroetinemia. Deficiency of this fat-soluble vitamin is associated with with ?
Oxidative stress to both neural and erythrocyte membranes.
This can happen with individuals with cystic fibrosis and the most common manifestations of Vitamin E deficiency are neuromuscular disease (skeletal myopathy, spinocerebellar ataxia, pigmented retinopathy) and hemolytic anemia.
93
What is the main form of therapy for disorders of the urea cycle?
Protein restriction: balance dietary protein intake and protein output, such that the body receives the essential amino acids needed for growth and development but not in excess such that excessive ammonia is formed.
Part of the urea cycle: Ornithing transport into mitochondria is essential for urea formation, as ornithine is needed to combine with carbamoyl phosphate w/in the mitochondria to form citrulline in the 2nd step of the urea cycle.
94
What disease causes a progressive neurological damage to the putamen?
Wilson's Disease.
95
What kind of drug is cholpheniramine?
It is a first gen H1-histamine receptor antagonist.
Note: This is the same as diphendydramine. Don't use with other meds that cause significant sedation, such as benzos.
96
What does this describe:
Progressive dementia, BEHAVIORAL DISINHIBITION and speech difficulties, such as dysarthria, aphasia, and echolalia.
Pick's disease: like alzheimer's, but confined to frontal and temporal lobes.
97
NF-1 neurofibromatosis is AD for defect on Chromosome 17.
What type of cells do these tumors stem from?
Neural crest-Schwannomas.
98
What is the acronym for organophosphate (farmers) poisoning?
DUMBELS
Diarrhea, Diaphoresis
Urination (stimulation of the smooth muscle fo the detrusor).
Miosis
Bronchospasm: Increased bronchial smooth muscle tone. Bronchoorreha (increased bronchial secretion) and bradycardia (decreased conductance)
E: Emesis (due to GI stimulation)
L: Lacrimation (along with stimulation of other secretory glands)
S: salivation.
All of the effects listed above are due to muscaric activation. ATROPINE blocks muscaric receptors, so can be used to treat....BUT it will not change the muscle paralysis because atropine does not work at the nicotonic receptor.
99
What is the only drug that can be used to treat organophosphate poisoning that will reverse both the muscarinic and nicotinic effects?
Pralidoxime
100
Occlusion of what vessel in the circle of willis will cause:
Contralateral weakness in the legs and sensory deficits of the contralateral legs, trunk and genitals.
Anterior cerebral artery
101
DNA polymerase that has 5' to 3' exonuclease activity
DNA polymerase (to remove RNA primer)-->also performs exonuclease excision and repair of damage to the parent DNA
102
When would you give an MAOI (like PHENYLZINE) to a depressed patient?
When they have ATYPICAL DEPRESSION or depression that has been resistant to other treatment.
Atypical depression: mood reactivity, leaden fatigue (the patient's arms and legs feel extremely heavy), rejection sensitivity, and the revered vegetative signs of INCREASED SLEEP and INCREASED APPETITE).
103
When you see neonatal intraventricular hemorrhage, where does it usually originate?
germinal matrix.
104
Measles can be very bad for the CNS.
What kind of virus is measles?
What antigen of this virus is missing in these patients?
What does it cause?
SUBACUTE SCLEROSING ENCEPHALITIS
1. Enveloped RNA virus of the Paramyxoviridae family.
2. Missing M protein
3. Subacute sclerosing encephalitis: occurs in children who appear of have recovered from measles infection several years earlier.
Note: the missing M antigen prevents the virus to be cleared by the immune system.
105
What enzymes in the heme biosynthetic pathway are most sensitive to lead inhibition (person living in 80 year old house scenario)?
delta-aminolevulinate dehydrase and ferrochelatase. (ALA--->porphobilingen) is compromised due to the dehydrase being messed up. Also (Protophorphyrin IX-->heme) is compromised due to ferrochelatase issues.
Delta-aminolevulinate synthase catalyzes the RATE LIMITING STEP in this pathway. Not inhibited by lead.
Glycine + Succinyl CoA------->delta-ALA
106
Review page 441 in FA of the visual field defects.
n/a
107
Why do tricylic antidepressants cause urinary retention?
They have anticholinergic side effects. (amytrypyline, for example). They are serotonin/norepi inhibitors, but also inhibit cholinergics somehow.
108
Damage to the __________ nucleus (most likely due to lacunar stroke) leads to hemiballism.
Subthalamnic nucleus of the basal ganglia.
109
What do you give to a patient treated for depression who has a prolonged QRS, hypotension and ventricular dysrhythmias?
This is TCA toxicity.
GIve sodium bicarb.
110
Motile gram negative rod that forms pink colonies on MacConkey agar that can cause meningitis in neonates.
virulance factor of this bug: Capsule that allows it to survive hematogenous spread and establish meningeal infection.
E. Coli
Note: Other causes of neonatal meningitis are group b step, listeria monocytogenes, Klebsiella. H. influenza, too, in nonimmunized infants.
111
What do you give to a patient following a subacute arachnoid hemorrhage that prevents the cerebral vascular spasm that typically follows these incidents?
Calcium channel blockers (NIMODIPINE)
112
How does B12 deficiency lead to gait instability and loss of sensation?
B12 is a cofactor for methylmalonyl CoA mutase. (Methylmalony CoA--->Succinyl CoA). Succinyl CoA is the final product of fatty acid oxidation that enters citric acid cycle. Deficiency of B-TWELVE leads to accumulation of methylmalonic acid, which can result in myelin synthesis problems.!
113
What drug do you use to either:
1. Diagnose myasthenia gravis, or
2. Know if you need to increase medication dosage of neostigmine or phyostigmine
Edrophonium
114
Images of brain scan.
Question ID: 794 [441651]
Review this information
115
Advanced Alzheimer's is associated with diffuse brain atrophy. EVen though it is diffuse, where is it most evident in the early stages?
Hippocampus.
116
Internuclear opthalmoplegia is associated with MS. What is it?
The eye that is adducting during a conjugate lateral gaze does not move.
117
What kind of drug is phenoxybenzamine?
Low-acting ALPHA-BLOCKER that is used for the treatment of PHEOCHROMOCYOTOMA.
118
HIV positive patient that is areflexive, has a positive Romberg sign and pupils that accommodate, but do not react to light.
What does he have?
Tabes dorsales, a form of neurosyphilis that involves the dorsal columns and dorsal roots of the spinal cord.
"whore's pupils": Both argyll robertson pupils and whores can accommodate but not react...L.O.L.
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What is the mechanism of action for Cochicine
Used to treat acute gout.
INhibits tubulin polymerization and microtubule formation in leukocytes, reducing neutrophil chemotaxis and emigration to sites inflamed by uric acid crystal deposition.
Side effect: Diarrhea, vomiting...GI mucosa adversely affected by colchicine.
