NBME 13 (Explanations
progressive weakness, dec strength, hand muscle atrophy, diffuse hyperreflexia and
fascicultations on hands and arms, normal sensory exam; - ANSW amyotrophic lateral
sclerosis (ALS)
--death of both upper and lower motor neurons in the motor cortex of the brain, the brain
stem, and the spinal cord
--Stephen Hawking disease
--*UMN and LMN signs*
--rapidly progressive weakness with fasciculations eventually leading to muscle atrophy,
spasticity, dysarthria, dysphagia, respiratory compromise, death from respiratory failure
UMN vs LMN weakness - ANSW --UMN weakness (brain to spinal cord) manifests in
hyperreflexia and rigid muscle tone, positive Babinski sign
--LMN weakness (anterior horn to muscle) manifests in muscle atrophy, decreased
reflexes, fasciculations, and flaccid muscle tone
history of numbness of fingers on left hand, loss of touch graphesthesia, loss of two
point discrimination in left hand - ANSW --lesion in somatosensory cortex on
contralateral side (right hemisphere)
--graphesthesia is the ability to sense what is being drawn or written via touch on their
hand
--the postcentral gyrus is a prominent structure in the parietal lobe of the human brain; it
is the location of the primary somatosensory cortex, the main sensory receptive area for
the sense of touch
missense mutation of tyrosine kinase domain of TrkA gene disrupts what process? -
ANSW phosphorylation of downstream molecules in response to nerve growth factor
--A tyrosine kinase is an enzyme that can transfer a phosphate group from ATP to a
protein in a cell. It functions as an "on" or "off" switch in many cellular functions.
Tyrosine kinases are a subclass of protein kinase.
--The presence of this kinase leads to cell differentiation and may play a role in
specifying sensory neuron subtypes. Mutations in this gene have been associated with
congenital insensitivity to pain with anhidrosis, self-mutilating behavior, mental
retardation and cancer
this part of the brain is affected most in chronic alcoholics - ANSW --anterior vermis
--a lesion in the vermis causes truncal ataxia, gait ataxia, and dysarthria
suppression vs. repression - ANSW suppression: mature defense
suppression is the voluntary withholding of an idea of feeling from conscious
awareness, like not thinking about an exam until the week of it or doctor controlling
anger at alcoholic pts he doesnt like
, repression: immature defense
repression is someone involuntarily withholding something from consciousness like not
remembering going to counseling for parents divorce
reaction formation - ANSW replace a bad/warded off feeling/idea with an emphasis on
its opposite; someone with libidinous thoughts enters a monastery
sublimation - ANSW mature reaction formation; replacing unacceptable wish with
action similar to wish but does not conflict with their values, like teens aggression
toward father redirected to perform well in sports
elderly woman with 1mo hx of urinary frequency and urgency, 3mo hx of walking
difficulty, problems with conversation and memory; normal strength and sensation; mini
cog average-normal; wide shuffling gait; ct shows enlarged ventricles - ANSW normal
pressure hydrocephalus
--*wet, wobbly, wacky* triad of urinary incontinence, ataxia, cognitive dysfunction
--expands ventricles that distort fibers of the corona radiata that lead to dementia,
ataxia, urinary incontinence
--does not increase subarachnoid space volume
--common in elderly and idiopathic
IHC positive for chromogranin indicates cancer of what origin? - ANSW neuroendocrine
or carcinoid
10% of pheochromocytomas are extraadrenal, occurring in
sites such as the organ of Zuckerkandl and the carotid
body, where they usually are called __ - ANSW paragangliomas, rather than
pheochromocytomas
Pheochromocytomas usually subscribe to a convenient
rule of 10s - ANSW --10% of pheochromocytomas are extraadrenal, occurring in
sites such as the organ of Zuckerkandl and the carotid
body, where they usually are called paragangliomas, rather than pheochromocytomas.
--10% of adrenal pheochromocytomas are bilateral; this proportion may rise to 50% in
cases that are associated with familial syndromes.
--10% of adrenal pheochromocytomas are malignant, although the associated
hypertension represents a serious and potentially lethal complication of even benign
tumors. Frank malignancy is somewhat more common in tumors
arising in extraadrenal sites.
--One "traditional" 10% rule that has since been modified
pertains to familial cases. It is now recognized that as
many as 25% of persons with pheochromocytomas and paragangliomas harbor a germ
line mutation in one of at least six known genes,
On microscopic examination, pheochromocytomas are
composed of: - ANSW polygonal to spindle-shaped chromaffin cells
progressive weakness, dec strength, hand muscle atrophy, diffuse hyperreflexia and
fascicultations on hands and arms, normal sensory exam; - ANSW amyotrophic lateral
sclerosis (ALS)
--death of both upper and lower motor neurons in the motor cortex of the brain, the brain
stem, and the spinal cord
--Stephen Hawking disease
--*UMN and LMN signs*
--rapidly progressive weakness with fasciculations eventually leading to muscle atrophy,
spasticity, dysarthria, dysphagia, respiratory compromise, death from respiratory failure
UMN vs LMN weakness - ANSW --UMN weakness (brain to spinal cord) manifests in
hyperreflexia and rigid muscle tone, positive Babinski sign
--LMN weakness (anterior horn to muscle) manifests in muscle atrophy, decreased
reflexes, fasciculations, and flaccid muscle tone
history of numbness of fingers on left hand, loss of touch graphesthesia, loss of two
point discrimination in left hand - ANSW --lesion in somatosensory cortex on
contralateral side (right hemisphere)
--graphesthesia is the ability to sense what is being drawn or written via touch on their
hand
--the postcentral gyrus is a prominent structure in the parietal lobe of the human brain; it
is the location of the primary somatosensory cortex, the main sensory receptive area for
the sense of touch
missense mutation of tyrosine kinase domain of TrkA gene disrupts what process? -
ANSW phosphorylation of downstream molecules in response to nerve growth factor
--A tyrosine kinase is an enzyme that can transfer a phosphate group from ATP to a
protein in a cell. It functions as an "on" or "off" switch in many cellular functions.
Tyrosine kinases are a subclass of protein kinase.
--The presence of this kinase leads to cell differentiation and may play a role in
specifying sensory neuron subtypes. Mutations in this gene have been associated with
congenital insensitivity to pain with anhidrosis, self-mutilating behavior, mental
retardation and cancer
this part of the brain is affected most in chronic alcoholics - ANSW --anterior vermis
--a lesion in the vermis causes truncal ataxia, gait ataxia, and dysarthria
suppression vs. repression - ANSW suppression: mature defense
suppression is the voluntary withholding of an idea of feeling from conscious
awareness, like not thinking about an exam until the week of it or doctor controlling
anger at alcoholic pts he doesnt like
, repression: immature defense
repression is someone involuntarily withholding something from consciousness like not
remembering going to counseling for parents divorce
reaction formation - ANSW replace a bad/warded off feeling/idea with an emphasis on
its opposite; someone with libidinous thoughts enters a monastery
sublimation - ANSW mature reaction formation; replacing unacceptable wish with
action similar to wish but does not conflict with their values, like teens aggression
toward father redirected to perform well in sports
elderly woman with 1mo hx of urinary frequency and urgency, 3mo hx of walking
difficulty, problems with conversation and memory; normal strength and sensation; mini
cog average-normal; wide shuffling gait; ct shows enlarged ventricles - ANSW normal
pressure hydrocephalus
--*wet, wobbly, wacky* triad of urinary incontinence, ataxia, cognitive dysfunction
--expands ventricles that distort fibers of the corona radiata that lead to dementia,
ataxia, urinary incontinence
--does not increase subarachnoid space volume
--common in elderly and idiopathic
IHC positive for chromogranin indicates cancer of what origin? - ANSW neuroendocrine
or carcinoid
10% of pheochromocytomas are extraadrenal, occurring in
sites such as the organ of Zuckerkandl and the carotid
body, where they usually are called __ - ANSW paragangliomas, rather than
pheochromocytomas
Pheochromocytomas usually subscribe to a convenient
rule of 10s - ANSW --10% of pheochromocytomas are extraadrenal, occurring in
sites such as the organ of Zuckerkandl and the carotid
body, where they usually are called paragangliomas, rather than pheochromocytomas.
--10% of adrenal pheochromocytomas are bilateral; this proportion may rise to 50% in
cases that are associated with familial syndromes.
--10% of adrenal pheochromocytomas are malignant, although the associated
hypertension represents a serious and potentially lethal complication of even benign
tumors. Frank malignancy is somewhat more common in tumors
arising in extraadrenal sites.
--One "traditional" 10% rule that has since been modified
pertains to familial cases. It is now recognized that as
many as 25% of persons with pheochromocytomas and paragangliomas harbor a germ
line mutation in one of at least six known genes,
On microscopic examination, pheochromocytomas are
composed of: - ANSW polygonal to spindle-shaped chromaffin cells
