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“Arrggg, here be fellow mateys seeking an explanation!”




... zevvyt is asking for clarification on nbme21/block4/q#27 (A 65-year-old woman is being treated in the hospital...)
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submitted by zevvyt(1)

Of all the things they can test us on, they're testing our fucking Gadar??

... weenathon is asking for clarification on nbme20/block3/q#8 (A 12-year-old girl is brought to the physician for a...)
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submitted by weenathon(1)

Anybody know why fatty acid degradation doesn't play a role?

... newrose is asking for clarification on nbme24/block3/q#2 (A 28-year-old man has a blood pressure cuff placed...)
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submitted by newrose(1)

Can someone clarify why Prostacyclin was wrong? I knew the CHALK thing but for some reason had trouble ruling out prostacyclin since it's a vasodilator

... stepwarrior is asking for clarification on nbme20/block4/q#10 (A 65-year-old woman who has a 25-year history of...)
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submitted by stepwarrior(0)

Wouldn't chronic alcoholism also reduce available NAD and thus inhibit pyruvate decarboxylation by PDH?

... stepwarrior is asking for clarification on nbme20/block4/q#34 (A 20-year-old man is brought to the physician by his...)
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submitted by stepwarrior(0)

You're just going to diss the son like that right in front of him?

... kllrsouth is asking for clarification on nbme16/block4/q#12 (39 yo woman, rheumatoid arthritis, follow-up examination)
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submitted by kllrsouth(0)

Couldn't the answer also be IL-2? Why can't you use cyclosporine in this patient with RA?

... misterdoctor69 is asking for clarification on nbme24/block4/q#47 (A 40-year-old man comes to the physician because of...)
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submitted by misterdoctor69(1)

Anyone else got thrown off by their use of HNPCC rather than Lynch syndrome?

... misterdoctor69 is asking for clarification on nbme24/block4/q#35 (An investigator is conducting a study of a novel...)
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submitted by misterdoctor69(1)

How come melanocytes:basal keratinocytes don't also have a desmosomal connection (in addition to their E-cadherin link)?

vivijujubebe  melanocyte is not part of the epidermal structure. they're at the epidermal-dermal junction and they produce melanin which is transported to the epidermal
... skip_lesions is asking for clarification on nbme21/block1/q#15 (A 35-year-old man comes to the physician because of...)
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submitted by skip_lesions(0)

Can't histamine also cause swelling or is it just not involved in the pathology of gout?

zevvyt  yes. Histamine causes vasodilation and increased vessel permeability. But it's not involved in Gout. Gout is more about Neutrophils and Macrophages activating eachother and not really about Mast cells.
... b1ackcoffee is asking for clarification on free120/block3/q#18 (A 51-year-old man comes to the office because of a...)
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submitted by b1ackcoffee(8)

Any good material for this and lymph node drainage in general? Is this common knowledge or low yield stuff?

mdmofongo  I got this question right thanks to the 100 high yield concepts of anatomy pdf, learn the lymph node drainage from there and you will be all right.
... b1ackcoffee is asking for clarification on free120/block2/q#31 (A 23-year-old woman is brought to the medical tent 2...)
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submitted by b1ackcoffee(8)

confused why this is not autonomic dysfunction or hyponatremia due to sweating and why is this orthostatic hypotension?

mdmofongo  This one is tricky and come downs to choosing the “best” option. I can see why you were confused. However do note that in an autonomic dysfunction you will never present tachycardia as this patient does. I guess the key here is seeing how her BP normalizes once she is laying down? Sorry, this one is a kinda unusual presentation of Orthostatic hypo.
mamed  Not sure if this is correct thinking but how I got this right was: 1. She is hypovolemic 2. Likely retaining salt so water follows (ADH or just renal dynamics in general). This is how I ruled our hypokalemia and hyponatremia 3. If she is hyponatremic b/c sweating then why wouldn't she also be hypokalemic? so both have to wrong because both can't be right 4. Volume depletion ==> orthostatic hypotension
... b1ackcoffee is asking for clarification on free120/block2/q#19 (A 7-year-old boy who lives in Kentucky is brought to...)
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submitted by b1ackcoffee(8)

I am wondering which parasite is this actually? --

mdmofongo  The clinical presentation sounds like a GI parasite, which are transmitted via fecal-oral route, so ingestion of soil would be the most sensible answer. All the other routes are of parasites with more severe or systemic infection.
b1ackcoffee  @mdmofongo I know this. But which parasite is this?
drblu92  The parasite is most likely Trichuris trichiura (human whipworm). Trichuriasis is often asymptomatic and adult forms can reach 2 cm in length (visible with naked eye). A lot more common in tropical areas but there have been cases in the southeastern US (ex: Kentucky). All other GI worms would present with either a fever or a cough. Treat with mebendazole or albendazole.
... amy is asking for clarification on nbme22/block3/q#45 (A 28-year-old man who is seropositive for HIV has...)
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submitted by amy(0)

HHV8 belongs to Herpesviridae family. Is it true that all members of this family have multinucleate cell with intranuclear inclusion body? HSV and VZV(cowry type A inclusion), EBV and CMV(owl-eye internuclear inclusion) certainly have them. Did anyone pick E for this reason?

... peridot is asking for clarification on nbme22/block4/q#22 (A 37-year-old man comes to the physician for a...)
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submitted by peridot(2)

While I understand why it's hyperplastic arteriosclerosis and how it classically occurs with HTN, I was wondering why it couldn't be berry aneurysm? Is it because the question is asking which is "most likely", making C the better answer? Thank you.

mannan  Berry Aneurysm is not CAUSED by HTN. It's caused by weakening of the arterial wall (at bifurcations). Hypertensive disease exacerbates them and causes the clinical picture of SAH (worst headache of life) when they rupture. Hope that helps -- Reference: FA CNS pathology, aneurysms.
... skip_lesions is asking for clarification on nbme22/block2/q#40 (A previously healthy 7-year-old girl is brought to...)
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submitted by skip_lesions(0)

Why would there be hyperkalemia if total body potassium is decreased in DKA?

drdoom  super high blood glucose; super high glucose spillage into urine; lots of peeing = volume depleted (“osmotic diuresis”)
alphatnf  because insulin normally stimulates Na/K ATPase, which sequesters K inside cell. lack of insulin means that there will be more K outside of the cell causing hyperkalemia. however, you are still total body K depleted due to osmotic diuresis. so the hyperkalemia is mainly due to a shift of K from the intracellular (where the vast majority of your K is inside your body is) to the extracellular space.
alphatnf  *where the vast majority of your K is inside your body
... pharmtomed is asking for clarification on nbme20/block4/q#5 (Immediately after a cerebral infarction, a...)
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submitted by pharmtomed(1)

Could anyone help me on why this couldn't be C (facial portion of the homonculus in the primary motor cortex)? It explicitly mentions motor issues with the face - not just speech. I understand why it would be Broca's - that's what I put originally. But the last sentence mentioning motor disruption caused me to change my answer. Thanks.

jaeyphf  I didn't even think about the motor part during the question, but it might be related to the homonculus (FA 2020 pg 502). Motor and sensory areas of the lower face generally fall towards the lower half of the brain. Answers B/C/D would probably show some hand or arm involvement.
... 123ojm is asking for clarification on nbme24/block3/q#25 (An investigator is studying a new virus isolated...)
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submitted by 123ojm(1)

Specifically didn't choose coronavirus due to the evidence that COVID-19 is spread fecal-orally. How does it get through the GI tract if it's inactivated by pH < 6? Can someone explain why my thinking is wrong?

hello  ...COVID-19 is transmitted via respiratory droplets.
123ojm  Right but some research has come out saying it's also spread fecal-orally. So I'm wondering what I'm missing in this question.
... trump2020 is asking for clarification on free120/block1/q#13 (A 26-year-old woman is brought to the emergency...)
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submitted by trump2020(4)

How do we know the inferior aspect of the tube doesnt rupture, releasing fluid down in between the layers of the broad ligament?

melchior  What is special about the Pouch of Douglas is that it is the lowest point of the peritoneal cavity, so even if blood gets in between the layers of the broad ligament (which I agree with you, it looks like it should), I bet it somehow makes its way down to the Pouch of Douglas due to gravity.
... joanmadd is asking for clarification on nbme21/block2/q#24 (A 65-year-old man dies in a motor vehicle collision....)
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submitted by joanmadd(1)

I know that small cell carcinoma wasn't an option in this question, but would there be any possible way to distinguish small cell from squamous cell on this specific gross pathology?

... irgunner is asking for clarification on nbme23/block1/q#7 (Which of the following is present in integral plasma...)
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submitted by irgunner(2)

I was thinking signal sequence on the N-terminal end that would direct the protein into the RER to be then implanted into the plasma membrane. I guess transmembrane region is the better more specific answer?

drdoom  A bilayer has hydrophobic tails (polar head + nonpolar tails). If the N-terminus could be embedded in there, it would also have to be hydrophobic; but if an N-terminus were hydrophobic, it wouldn't dissolve well in the cytosol (=mostly water). In fact, an N-terminus probably wouldn't dissolve at all. If it were hydrophobic, it would aggregate with other, nearby N-terminuses (or other hydrophobic motifs). But if that happened, shuttle proteins couldn't recognize N-terminuses in the first place (they wouldn't be sterically accessible), nor deliver them to the rER.
... arkanaftus is asking for clarification on nbme20/block1/q#35 (A 70-year-old man dies of coronary artery disease....)
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submitted by arkanaftus(5)

Is it appropriate to ask a question about the structure which is absent on the picture? It was super confusing! How can you say it was not a defect of the tissue cut?

drdoom  why did this get downvoted?
... therealslimshady is asking for clarification on nbme24/block1/q#10 (A 75-year-old man is brought unconscious to the...)
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submitted by therealslimshady(5)

Given the diagnosis of AAA, why did he have syncope? I was first thinking it was from rupture, but his blood pressure is not hypotensive, so how could he get syncope from that.

Or maybe the AAA was compressing the inferior vena cava, causing syncope?

... mdmikek89 is asking for clarification on nbme22/block3/q#45 (A 28-year-old man who is seropositive for HIV has...)
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submitted by mdmikek89(-7)

Spindle cells....sarcoma or carcinoma

Kaposi *Sarcoma*...

Why y'all make this shit so complicated?

drdoom  This explanation only begs the question. (It's a tautology.)
... haozhier is asking for clarification on nbme21/block2/q#35 (A 4-month-old female infant is brought to the...)
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submitted by haozhier(3)

Why is it not hypoglycemia?? Hypoglycemia can also lead to seizure

cuthbertallg0od  Same thoughts here, and I think hypoglycemia occurs earlier in kids/infants than in adults (like 8 hours?) -- maybe just more likely to be hyponatremia since Na+ lost in the diarrhea...
... waterloo is asking for clarification on nbme20/block2/q#26 (A male newborn is found to have a decreased blood...)
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submitted by waterloo(23)

If you think about it this way, his free T4 is normal and his TSH is normal. Would any other option allow this to happen?

A step further would be, why is his free serum T4 okay but his T3 and T4 dec. His total T4 must be decreased then, which one of those can cause that while keeping free T4 normal.

... waterloo is asking for clarification on nbme20/block3/q#42 (A 13-year-old girl has an episode of severe cellular...)
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submitted by waterloo(23)

when CMV is involved in post transplant patients that typically causes pneumonia. I think that was a question in this NBME too. For EBV post transplant, it would be lymphadenopathy etc. That's what I've taken away so far from nbme. I thought maybe the monomorphous B lymphocytes was hinting more towards EBV too, but I don't see why CMV wouldn't remain latent in a B lymphocyte?

... haozhier is asking for clarification on nbme20/block3/q#47 (A 60-year-old woman has prolonged apnea following...)
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submitted by haozhier(3)

From FA, succinylcholine can be reversed during phase 2 by cholinesterase inhibitor. Can someone explain if succinylcholine is metabolized by cholinesterase, how can we use cholinesterase inhibitors to reverse it?

... castlblack is asking for clarification on nbme22/block1/q#32 (A 17-year-old boy is brought to the emergency...)
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submitted by castlblack(8)

I have read all the comments, but none explain why hyponatremia is wrong. There is definitely Na+ in stool....thats why sugar+salt is rehydration for peds diarrheal sickness. Low Na+ causes low EVV explaining the low BP, high HR, pallor, and dehydration. Is it correct but just not as correct as C?

waterloo  I Dont know what you mean by low EVV. But here's my thought process. This pt lost lots of water, and when someone takes a laxative causing them to have diarrhea that will lead to metabolic acidosis. A buffering mechanism for the decreased bicarb in the blood is for H+ to leave cells and K+ to go into the cells. So he has to have hypokalemia (low K+ in serum). They gave him IV fluids, so his BP should be headed back to normal. I would think his RAAS will chill out. But it takes time to correct the acidosis, you're kidney won't just immediately stop reabs bicarb so you're body will still be buffering against the acidosis (H+ out of cell, K+ in).
waterloo  sorry, I wrote increased bicarb, I meant DECREASED bicarb in the blood. And also should have written "you're kidney won't just immediately START reabs new bicarb" My Bad, wasn't trying to add to confusion.
drdoom  i think by `EVV` author meant `ECV` (extracellular volume). @waterloo, appreciate the explanation but think something is off: loss of HCO3- via diarrhea should result in acidemia, which would oppose the presumption of ‌``H+ leaving cell, K+ going in´´.
waterloo  hey so sorry, I must have been super tired posting this. Can't believe I made so many mistakes. Read over it again, and it sounds like gibberish. Wish there was a way to delete. My bad.
waterloo  I think I tried to explain too hard. Looking at this question again, I think really the only this is when you lose that much volume, you lose bicarb and K+. Nothing really to do with acid-base. My b.
drdoom  no worries!
... castlblack is asking for clarification on nbme22/block1/q#11 (A 6-month-old boy has recently been diagnosed with...)
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submitted by castlblack(8)

Huh. Who else thought this was Gaucher until you had to pick D?

elephantbuddy  I think that the hepatosplenomegaly is definitely a common characteristic but you would see more bone abnormalities in Gaucher. This patient has no bone crises and exhibits developmental delay, HSM, and foam cells which is more characteristic of Niemann-Pick.
... demihesmisome is asking for clarification on nbme21/block2/q#8 (A 55-year-old man is diagnosed with renal artery...)
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submitted by demihesmisome(1)

So I must have misunderstood - the arcuate arteries are in the cortex which is why I picked cortex - but we're saying the renin will always be highest in the cortex? - p. 564 FA

... haozhier is asking for clarification on nbme24/block2/q#40 (A 4-year-old boy has a 1-cm round midline mass just...)
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submitted by haozhier(3)

Can someone please explain to me: If the posterior 1/3 of the tongue is developed from 3rd and 4th pharyngeal arches, why is it wrong to choose pharyngeal arch?

therealslimshady  Welcome to NBME
... ankirin is asking for clarification on nbme20/block1/q#13 (A 6-week-old girl is brought to the physician by her...)
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submitted by ankirin(2)

What is esophageal spasm and how would it present differently?

baja_blast  I had narrowed it down to that and the correct answer. I think the difference is that esophageal spasm tends to present with pain and dysphagia. FA 2019 p. 371, right at the top of the page.
orthonerd  Relating the phrase "diffuse painful contraction" to esophageal spasm has helped me remember the associated descriptions they go to.
... b1ackcoffee is asking for clarification on nbme24/block3/q#42 (Which of the following terms best describes the...)
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submitted by b1ackcoffee(8)

Any good material to prepare for this kind of stuffs?

apurva  Lord Jesus
... haozhier is asking for clarification on nbme24/block4/q#5 (A 45-year-old man comes to the physician because of...)
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submitted by haozhier(3)

How do you guys know about this? I chose stool O&P...and muscle biopsy is not mentioned anywhere...

misterdoctor69  Sketchy micro!
... fexx is asking for clarification on nbme23/block4/q#12 (Investigators conduct a prospective, community-based...)
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submitted by fexx(4)

wtf kinda question was this? where the hell am i even going to use these concepts in medicine?!

... bking is asking for clarification on nbme22/block2/q#5 (A 74-year-old man with emphysema and lung cancer is...)
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submitted by bking(1)

I understand the edema is from decreased protein- why is Starvation Ketosis wrong? Couldn't his proteins be degraded through this process: Protein--Amino acids-- Acetyl CoA-- Ketones

waterloo  negative nitrogen balance better explains the edema.
... llamastep1 is asking for clarification on nbme23/block1/q#41 (A 62-year-old woman is brought to the emergency...)
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submitted by llamastep1(15)

So did I just get lucky? I just did rule of 4s, bilateral motor meant medial and I interpreted horizontal eye movement as CN6 which is also medial and pons(CNs 5,6,7,8). Couldn't really place the disarthria but medial pons seemed like a good option.

... alexxxx30 is asking for clarification on nbme23/block3/q#17 (A 24-year-old woman comes to the physician because...)
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submitted by alexxxx30(10)

did anyone else have to reread this question several times? The jumping back and forth from "this happened before, 1 week after, 6 weeks after" then this happened today, then" this happened 6 weeks postop" gave me whiplash. Tell the story in order! haha

... drschmoctor is asking for clarification on nbme24/block2/q#6 (A 50-year-old woman is admitted to the hospital for...)
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submitted by drschmoctor(45)

How does one differentiate factitious disorder from being thirsty w poor impulse control?

therealslimshady  If you're asking how to rule out diabetes insipidus, I think it's because: Diabetes insipidus is caused by a lack of ADH effect, so they will be peeing out too much water, thus making them dehydrated and hyperosmolar (thirsty). This CHF patient is presenting with signs of fluid overload
... jinzo is asking for clarification on nbme23/block4/q#32 (A 42-year-old woman comes to the office because of a...)
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submitted by jinzo(10)

I have ganglion cyst since 2012 and this shit doesn't disappears . Moreover , it may cause some pain , when I flex my wrist . So why answer is not parasthesia???

asharm10  I am sorry bus this is soo funny!! I hope your's spontaneously regresses too
lowyield  Not sure exactly but my guess is that it doesn't impinge upon any major nerve (yes it can probably impinge some superficial branches of the radial)
... donttrustmyanswers is asking for clarification on nbme23/block2/q#33 (A 68-year-old man who has been treated for the past...)
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submitted by donttrustmyanswers(14)

I just realized there were solid arrows and dashed arrows in the image. Is there a significant to the dashed arrows vs the solid arrows?

... donttrustmyanswers is asking for clarification on nbme23/block2/q#25 (A 44-year-old man with invasive pancreatic cancer is...)
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submitted by donttrustmyanswers(14)

What is the area labeled 'G' and 'C'? And more characters?

alexxxx30  lateral corticospinal i think
... justherefortheyield is asking for clarification on nbme23/block1/q#25 (A 5-year-old boy who is undergoing induction...)
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submitted by justherefortheyield(1)

Per multiple sources: measles can be vesicular and also can lead to giant cell pneumonia in the immunocompromised. ?!?!?!?

elephantbuddy  I was stuck on that too, but I think that measles more commonly presents with a maculopapular rash whereas a vesicular rash is more typical of VZV.
... justherefortheyield is asking for clarification on nbme23/block3/q#46 (A 19-year-old woman is severely burned over 35% of...)
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submitted by justherefortheyield(1)

Couldn't hypoalbuminemia lead to hypercholesterolemia? I recall sittar talking about this in the context of proteinuria but couldn't this still apply?

frustratedllama  I thought so too but did a little digging and turns out this happens in nephrotic syndrome bc low oncotic pressure directly stimulates apolipoprotein B synthesis. They still don't know why lol. But in burn victims there's actually increased lipid metabolism, so nothing to do with hypercholesterolemia.
... dr_pepper is asking for clarification on nbme21/block4/q#34 (A healthy 8-year-old boy is brought to the physician...)
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submitted by dr_pepper(-1)

Quick google search reveals that methylphenidate works by inhibiting dopamine and NE reuptake, Am I missing something here? How is this "release of biogenic neurotransmitters"?

bharatpillai  methyl phenydate and amphetamines act by both stimulating release and inhibiting uptake. cocaine and tcas primarily acts by inhibiting uptake think about it this way- meth is purified and made in the lab so it's more effective at increasing NE and DA levels in the synapse.
... ibestalkinyo is asking for clarification on nbme21/block3/q#8 (A 55-year-old woman is brought to the emergency...)
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submitted by ibestalkinyo(21)

Anyone find it strange that the NBME loves to write questions where physicians are alcoholics?

athenathefirst  Their job is to find our flaws haha
... b1ackcoffee is asking for clarification on nbme21/block2/q#14 (A 30-year-old woman comes to the office because she...)
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submitted by b1ackcoffee(8)

exactly how does maternal hashimoto can cause cretinism?

... snoochi95 is asking for clarification on nbme23/block1/q#36 (A medical student is caring for a 72-year-old man...)
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submitted by snoochi95(1)

How come you couldnt say "I dont know, but the oncologist will be seeing you later today"? Is it because technically you are ~lying~ to the patient?

drdoom  Not “technically” but actually! To say “I don’t know” when you *do* know is as lyin’ as it gets! Just remember, before a state issues you a license to practice medicine in their backyard, they look to the National Board of Medical Examiners and ask, “Should we trust this person to practice medicine here?” The NBME is in the business of telling states, “Yes, we believe this person knows enough to practice morally and competently.” Answer ethics questions with this in mind.
pseudo_mona  Besides technically lying, it also probably isn't a good idea to drop the word "oncologist" to a patient before they hear they have cancer, especially as a student who can't answer any further questions about the biopsy results.
... targetmle is asking for clarification on nbme24/block4/q#6 (A 68-year-old woman comes to the physician because...)
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submitted by targetmle(1)

if the option had SMA and celiac trunk, would that be correct?

... targetmle is asking for clarification on nbme24/block4/q#24 (A 13-year-old girl who has a 6-year history of type...)
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submitted by targetmle(1)

Shouldn't we first address the issue by correcting her glucose levels by readjusting insulin and then see what are the problems?

... the_enigma28 is asking for clarification on nbme21/block4/q#29 (A 22-year-old man comes to the physician because of...)
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submitted by the_enigma28(3)

Is there any drug which would cause enhancement of cell membrane permeability to chloride? It seems like the MOA of ETEC & V. cholerae adenylate cyclase toxins and somewhat that of Ivacaftor used in cystic fibrosis.

... the_enigma28 is asking for clarification on nbme21/block1/q#49 (An 80-year-old woman comes to the emergency...)
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submitted by the_enigma28(3)

Can anyone explain what does "lost her pep" means?

drdoom  `pep` actually comes from `pepper`; to `pepper` something (including a food dish!) is to make it more vigorous, to give it more kick, to vitalize it. so, to “lose one’s pep” is to lose one’s vitality, feel fatigued, feel lackluster, etc. https://www.etymonline.com/word/pep
... hungrybox is asking for clarification on nbme23/block2/q#15 (A child with septicemia has an antibiotic clearance...)
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submitted by hungrybox(586)

Fucking NBME test writers lmao

Me: "Wait... isn't the answer 25.9? How come I don't see it here."

NBME: "Oh yeah, we rounded it."

Me: "To 30? I don't see that here, either..."

NBME: "No, to 28.8"

tyrionwill  When I got 25.9 and found nothing exactly matched, I guessed that the maintenance dose might be a bit more due to the bioavailability. So this antibiotic probably was not an I.V. formula, but an oral one, with a roughly 90% BA.
eradionova  Well then it could have been equally likely that it had a 50% BA and the answer would be 51.8 exactly. I almost considered picking that but in the end stuck with the one that was closest to my answer lol
... haozhier is asking for clarification on nbme23/block3/q#23 (A pregnant 28-year-old woman is found to have...)
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submitted by haozhier(3)

I chose corticotrope because I thought during pregnancy women have more cortisol. Can anyone explain it for me? Thanks!

... haozhier is asking for clarification on nbme23/block2/q#19 (A 70-year-old man with severe congestive heart...)
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submitted by haozhier(3)

I chose C because I thought it has been four weeks so it must have been acute tubular necrosis. Can anyone explain? Thanks!

miriamp3  @haozhier if you are deciding to think that he had a ATN because of the 4 weeks.. then he should be by now in the recovery phase(polyuria, Bun/cr fall) But he is with HF and his urine output has progressively decrease. So AKI prerenal HF Bun/cr >20. the only one is D. Don't get confused with the rest of the information.
jesusisking  I thought the same thing so chose C as well!
... thotcandy is asking for clarification on nbme23/block1/q#17 (A 54-year-old woman comes to the physician because...)
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submitted by thotcandy(21)

What is there that rules out deltoid? overhead abduction is >15' so shouldn't that point more towards deltoid?

baja_blast  Deltoid only does abduction from 15 to 90 degrees. So not overhead.
donttrustmyanswers  With that logic, supraspinatus only does abduction form 0-15
rina  the positive empty can test is the biggest thing "pain and weakness with abduction, particularly with simultaneous shoulder internal rotation" - that tells you it has to be one of the SITS muscles (supraspinatus, infraspinatus, teres minor, subscapularis), not the deltoid. tenderness in the right deltoid region tells you it's the supraspinatus which is right underneath the deltoid muscle
... thotcandy is asking for clarification on nbme23/block2/q#33 (A 68-year-old man who has been treated for the past...)
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submitted by thotcandy(21)

Everyone asking why not PPIs?

if you give NSAIDs which decrease PGs so you get GERD, the simplest way to fix it is to bring those PGs back, so misoprostol.

Just simply -PGs --> +PGs

hungrybox  This is the best explanation IMO Also makes me feel like an absolute idiot
... vinniewolf17 is asking for clarification on nbme24/block4/q#20 (Forty of 100 attendees at a company Christmas party...)
 -1  upvote downvote
submitted by vinniewolf17(-1)

Anyone going to mention that C. perfringens has been demonstrated to have a high association with gastritis and shellfish and that parahaemolyticus is a cause of necrotizing fasciitis?

tiredofstudying  FA 2020 Pg 178.
... snoochi95 is asking for clarification on nbme22/block3/q#47 (A 10-year-old boy receives a renal transplant from a...)
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submitted by snoochi95(1)

Does anyone know why this is not Chronic rejection? They both fit within the time frame.

... hombremasorca is asking for clarification on nbme20/block3/q#19 (A 23-year-old man comes to the physician because of...)
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submitted by hombremasorca(0)

Anyone find a problem with the stem? Seems to me that it doesn't help to state "however, his father's sister and children are unaffected". We already know the mutation runs in the mother's side, right? It seems like that statement doesn't discard nor confirm any inheritance pattern. Why would we care about the patient's father's side?

bbr  It just further helps to tell us this is mitochondrial. I guess they are doing us a favor.
... banana is asking for clarification on nbme18/block4/q#4 (36 yo woman, 2 weeks of fatigue, bleeding gums, bone pain)
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submitted by banana(3)

I thought (incorrectly, obviously) that histone kinase also allowed transcription to proceed?

banana  Just kidding, dead wrong: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3469451/ histone-P demarcates DNA breakage for repair
... bharatpillai is asking for clarification on nbme21/block2/q#24 (A 65-year-old man dies in a motor vehicle collision....)
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submitted by bharatpillai(13)

am i the only one who chose mesothelioma? didnt that look like a pleural plaque posteriorly to anyone?

brotherimodu  That's what I thought too.
... rainlad is asking for clarification on nbme22/block3/q#16 (A 27-year-old woman comes to the physician because...)
 -1  upvote downvote
submitted by rainlad(13)

How do you rule out Protein C deficiency in this case? doesn't that also increase risk of thrombosis and miscarriage?

suckitnbme  @rainlad Protein C deficiency doesn't cause elevated PT and aPTT. I believe they're both normal and assays for the disease measure protein C activity.
drzed  Protein C is an anti-coagulant, so if you lack factor C, then you have MORE clotting factors. This means that the PT and PTT would not be prolonged.
... sammyj98 is asking for clarification on nbme18/block2/q#8 (39 yo man, polycystic kidney disease)
 +1  upvote downvote
submitted by sammyj98(10)

did anybody else second guess the heck out this answer just because he's got a pH of 7.2 and he's hanging out in an outpatient clinic? I haven't done my clinicals yet but it seems like this guy would be struggling..

myoclonictonicbionic  EXACTLY... 7.2 for 6 months without any drastic symptoms.. that doesn't sound right
... pg32 is asking for clarification on nbme22/block2/q#23 (A 32-year-old woman comes to the physician because...)
 +1  upvote downvote
submitted by pg32(64)

How did anyone get this as T cruzi? That was literally the first answer I ruled out. She has swelling of the eye, but that is the only sx that fits. Chagas presents 10-20 years after initial infection, not two weeks later. It also doesn't present with recurrent fever, muscle aches and joint pain. I mostly ruled it out because of the time course.

castlblack  I made the same mistake. Tsetse flies only exist in africa. African sleeping sickness is named well. Chagas is only in south america/central. Leishmaniasis is found on both continents.
medjay7  The clinical presentation confused as hell, but I could recognize that Trypomastigote anywhere and definitely was not African sleeping sickness.
... abhishek021196 is asking for clarification on nbme22/block1/q#24 (A 48-year-old man with renal artery stenosis...)
 -1  upvote downvote
submitted by abhishek021196(11)

This question in it's essence is asking that after inserting the catheter in the femoral artery, which landmark should we use beyond which superiorly lies the renal artery, and the answer is the origin of the testicular artery. What a weirdly worded question though. :?

makinallkindzofgainz  I don't think it's worded that weirdly. The guide wire should be advanced superiorly just beyond the testicular artery to approach the right renal artery.
... dentist is asking for clarification on nbme22/block1/q#6 (A 2-month-old boy is brought to the physician...)
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submitted by dentist(29)

So do you ignore the distraction about his mother and consider which of the organisms can lead to nodule formation on the vocal cord?

neovanilla  yep _(ツ)_/¯
... neovanilla is asking for clarification on nbme20/block4/q#41 (A 56-year-old man with a 20-year history of chronic...)
 -1  upvote downvote
submitted by neovanilla(23)

The crux of the question is asking, if the patient feels decreased pain (which is driven by opioid molecules; that's why opioids are administered as painkillers), then how do you stop the inhibition? An opioid antagonist (naloxone is the only one that is an antagonist)

neovanilla  wrong answers: b-endorphin - an endorphin and ACTH hormone (similar to ACTH, POMC) that can bind to the µ-opioid receptor Enkephalin - a neurotransmitter involved in the indirect basal ganglia pathway (along with GABA); it can also bind to delta-opioid receptors Morphine - an opioid agonist (used for pain relief) Oxycodone - Another opioid agonist (~same potency as morphine)
... dartosfascia is asking for clarification on nbme24/block1/q#42 (A 68-year-old woman with acute myelogenous leukemia...)
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submitted by dartosfascia(0)

Why would you give GMCSF to someone with AML?? Isn't the whole goal of treatment to knock out the granulocytes? I feel like giving someone GMCSF after they were JUST treated for AML is asking for a relapse but what the hell do I know.

drdoom  The problem in AML (acute myeloid leukemia) is that precursor cells “get stuck” on their way to becoming (mature) granulocytes. Giving GM–CSF “pushes” them toward a more differentiated state and, because they divide as they mature, the cells become vulnerable to drugs that disrupt cell division (replication): “Granulocyte–macrophage colony-stimulating factor (GM–CSF) can stimulate proliferation of leukemic blasts and sensitize these cells to the cytotoxic effects of S-phase–specific drugs.” https://www.nature.com/articles/2402368
... sammyj98 is asking for clarification on nbme20/block2/q#35 (A 36-year-old woman comes to the office because of a...)
 +1  upvote downvote
submitted by sammyj98(10)

maybe I overthought this one, but doesn't she have free air in the bottom left? Or is that the bottom of the pleural space...

ibestalkinyo  That's probably the most inferior portion of the right lung
... pg32 is asking for clarification on nbme20/block4/q#48 (A 24-year-old man comes to the emergency department...)
 +0  upvote downvote
submitted by pg32(64)

Can anyone explain why the lipase concentration is so high if there is an issue with LPL in hyperchylomicronemia?

garima  due to pancreatitis
neovanilla  ELI5?
suckitnbme  @neovanilla Type 1-hyperchylomicronemia has increased risk of pancreatitis
... jinzo is asking for clarification on nbme20/block3/q#19 (A 23-year-old man comes to the physician because of...)
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submitted by jinzo(10)

A - nucleus ( with nucleolus inside ) B - mitochondria C - RER ( you can see attached ribosomes ) D - ?? may be lysosomes E - glycogen granules

weenathon  I don't think A is the nucleus, It seems more like a lysosome with digested material inside. If you watch the video below it shows the relative size of the nucleus to the mitochondria - a nucleus would be MUCH bigger than the mitochondria
weenathon  https://www.ncbi.nlm.nih.gov/books/NBK26858/ There are very similar looking pictures in this article, it must be a peroxisome
... rainlad is asking for clarification on nbme21/block3/q#12 (A 55-year-old man with hypertension comes to the...)
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submitted by rainlad(13)

How do we explain the bruit in this case? Also why isn't it left artery aneurysm? That seems like it would better explain the bruit

gdupgrant  The bruit is basically just turbulent flow, which is most commonly caused by artery narrowing. I was just reading https://emedicine.medscape.com/article/463015-clinical on renal artery aneurysm and it looks like most of the hypertension is actually related to a pre aneurysm stenosis, so i think stenosis is the "better" answer, esp. since the pt has like every risk factor for stenosis. To be honest I had not ever really thought about RAA for this case because bruit over RA has been drilled into my head as renal artery stenosis, but i apprecaite seeing how this is a super reasonable answer - just the stenosis is "more likely"
... rainlad is asking for clarification on nbme21/block3/q#38 (A 28-year-old man develops a temperature of 39.9°C...)
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submitted by rainlad(13)

would we be worried about using G-CSF given that he has acute leukemia? would it stimulate growth of his cancer cells?

suckitnbme  I think we're assuming that we eradicated the leukemia with the chemo. However at the same time a lot of normal stem cells were also killed off so we give GCSF to help recovery especially since they have an infection.
... drbravojose is asking for clarification on nbme22/block2/q#23 (A 32-year-old woman comes to the physician because...)
 +1  upvote downvote
submitted by drbravojose(2)

FA 2019 p156 Does anyone know how to differentiate the picture labeled Trypanosoma brucei and cruzi?

footballa  This question is likely not important for two reason: They're both Trypansomastigotes, so of course they look almost the same. You can differentiate these two species clinically as they have very little clinical similarity in patient presentation. For these reasons there's little to no reason you would be expected to differentiate these two species by histology alone
snripper  Does Chagas have recurrent fever? Because that's what pointed me to African Sleeping Sickness.
baja_blast  The history of travel to the Amazon is what pointed me to Cruzi over Brucei but agree it's a tough distinction to make here. In the absence of that detail I would have probably picked Tsetse fly.
... readit is asking for clarification on nbme21/block1/q#25 (A 28-year-old man is brought to the emergency...)
 +0  upvote downvote
submitted by readit(9)

Why is is not pseudo aneurysm?

"Aortic pseudoaneurysms typically occur as a result of trauma +/- intervention, a considered subset of traumatic aortic injury in the majority of cases. They can be acute or chronic."

https://radiopaedia.org/articles/aortic-pseudoaneurysm?lang=us

readit  *same goes for saccular aneurysm, which also is usually 2/2 trauma
samsam3711  In the question stem there is no indication of trauma so it would be hard to just assume that
almondbreeze  see my comment above for marfan syndrome. might help
drzed  This is because a pseudoaneurysm is between the media and adventitia, and is incited by trauma; a dissection is between the intima and the media and is a result of hypertension causing an intimal tear. The history points toward cocaine -> hypertension rather than penetrating trauma.
... ilovemypuppies2295 is asking for clarification on nbme20/block2/q#29 (A 25-year-old woman has a flu-like illness (fever,...)
 +0  upvote downvote
submitted by ilovemypuppies2295(0)

What makes this coxsackie virus over Adenovirus? Both cause myocarditis which would be seen on autopsy? Is it just more common to get coxsackie?

drdoom  the general consensus appears to be that Coxsackie is more common than Adenovirus, but i haven’t come across any papers or textbooks that would agree (they only mention “Coxsackie” and “Adenovirus” as associations with myocarditis)
bharatpillai  there specifically is a question on uworld in which a young woman gets viral myocarditis with sore throat and the answer to that is adenovirus. i think thats why many people (including me) got it wrong :(
... qfever is asking for clarification on nbme20/block3/q#19 (A 23-year-old man comes to the physician because of...)
 +1  upvote downvote
submitted by qfever(16)

Does anyone know what are A, C, D? For C not sure if it's pointing to the ribosomes on RER.

(I'm assuming E is glycogen granules based on a comment below!)

... lilyo is asking for clarification on nbme18/block4/q#29 (65 yo man, cancer of the cecum)
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submitted by lilyo(34)

Anyone have an idea on how to approach this question?

gdupgrant  So the thing i think they tried to catch people on was that the SMV Joins with the splenic to become the portal vein and the IMV feeds into the splenic vein. And they want you to know that cecum is midgut, so drained by the SMV. so my approach was automatically eliminate any answer that included IMV or Splenic vein and that left me with only Ileocolic → superior mesenteric → portal → right hepatic branch of the portal
... poisonivy is asking for clarification on nbme24/block4/q#12 (A 25-year-old woman takes an overdose of...)
 +0  upvote downvote
submitted by poisonivy(20)

can we consider the overdose as a suicidal attempt? if so... wouldn't she be considered as without decision-making capacity?

em_goldman  People who are suicidal still have decision-making capacity; it's not equivalent to advanced dementia or other situations where decision making is impaired. Laws vary by state; I know in my state that the maximum time for holding someone against their will is 48 hours unless a court has deemed them incompetent and designated another person as their legal decision maker, including people who are actively suicidal. My understanding of the law as a layperson is that her living will was signed along with people bearing witness to the fact that she was the one who signed it, and it was what she wanted. Ethics aside, it would be almost impossible to prove that she legally initiated a DNR in a state of suicidality that was intense enough to interfere with her decision-making capacity in that moment.
... mahitha is asking for clarification on nbme19/block2/q#5 (38 yo woman, 6 months depressed mood, joint pain, weakness, memory problems + erythema migrans)
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submitted by mahitha(0)

Can anyone PLZZ explain how lymes disesa has memory problems and depressed mood?

drdoom  Chronic inflammation, and the persistent elaboration of cytokines that go along with it, can cause all sorts of unusual and nonspecific problems, including cognitive compromise. (Just imagine how you might feel if you had low-grade fever for, say, a decade.) Patients who have suffered significant cardio- or cerebrovascular “events” report depressed mood following the event. My guess is that the memory problems can be from chronic inflammation or as a result of spirochete vasculitis which, over time, results in a kind of vascular dementia (“multi-infarct”). You see spirochete vasculitis (of the thoracic aorta), as well as vascular dementia, in another famous spirochete, Treponema pallidum, the culprit behind Syphilis.
... mrglass is asking for clarification on nbme20/block3/q#35 (A 51-year-old man has the acute onset of fever and...)
 +0  upvote downvote
submitted by mrglass(15)

Why would this not be acute transplant rejection leading to ARDS? The creatinine is elevated, and I see any reason why it would be elevated beyond rejection

sammyj98  I selected the same. I think part of the question wanted us to recognize that the pt was not receiving CMV prophylaxis (hinted that they are getting TMP-SMX but no Gancyclovir) so they're at really high risk for CMV specifically. UpToDate: •Universal prophylaxis with valganciclovir or ganciclovir is typically given to patients at risk for cytomegalovirus (CMV) reactivation (eg, seropositive recipients and those with seropositive donors). The duration of therapy often depends on the type of organ transplanted, the risk status of the patient, and individual institutional practice. Some transplant centers prefer to use a pre-emptive approach (eg, routine CMV viral load monitoring within initiation of treatment when reactivation becomes evident) for specific patient populations. (See 'Cytomegalovirus' above.)
... brookly_ is asking for clarification on nbme23/block4/q#33 (A 16-year-old girl with bulimia nervosa is brought...)
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submitted by brookly_(0)

I thought bulimia give rise to metabolic alkalosis ...can someone elaborate ?

drdoom  Remember, bulimia itself does not mean “purging”; it means “ox-hunger”. It is purging (e.g., intentional vomiting, laxative abuse, diuretic abuse, excessive exercise, or extreme fasting) which creates metabolic disturbance. The type of disturbance depends on your preferred route of “exit”.
... divya is asking for clarification on nbme23/block2/q#3 (A prospective study is done to assess the relative...)
 +3  upvote downvote
submitted by divya(37)

okay but where in the question is it asking whether it's intention to treat or per protocol or as treated???

are we to assume its ITT if they don't mention anything or the part of the question that says "primary analysis" the giveway to ITT??

kpjk  I had the same doubt. I think if we were to consider "per protocol" then answer would have to be a mash of options A and B. There is no option that would be right for per protocol
peqmd  I think ITT is assumed b/c it's the one that has reduced biased in measurements.
... mikay92 is asking for clarification on nbme24/block1/q#42 (A 68-year-old woman with acute myelogenous leukemia...)
 +0  upvote downvote
submitted by mikay92(0)

Did anyone else find this question painfully poorly written? I spent so long just trying to figure out what the heck they were asking.

It's as if they don't want us to do well...

drdoom  I don’t think the NBME ever “intends” to write an ambiguous or poorly worded stem. What they want to do is write questions whose response choices are not “blatantly obvious” but which do have a single, “most correct” choice. That’s actually surprisingly difficult! If the correct choice were “obvious”, the test would not be doing a good job assessing anyone’s ability to make subtle judgment calls (an important skill, one might argue, in the morass that is the real world); this is also the reason they eschew “buzzwords”, generally. If a stem has two or more choices that are “equally correct”, the same lapse has occurred: they would be failing to assess the capacity to make subtle judgment calls.
drdoom  All that said, please see this perfect metaphorical description of all Step 1 questions: reddit.com/r/step1/comments/4jegfu/took_step_1_wanted_to_share
... blueberrymuffinbabey is asking for clarification on nbme23/block2/q#3 (A prospective study is done to assess the relative...)
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submitted by blueberrymuffinbabey(1)

I got this one wrong, but based on the ITT perspective others mentioned, maybe the "in their primary analysis" part of the question is a tip off. They'd start with including them in the original groups and then do additional analysis to try and tease out the impact? IDK

... diabetes is asking for clarification on nbme23/block3/q#49 (Genetic analyses of cells obtained on amniocentesis...)
 -1  upvote downvote
submitted by diabetes(14)

how is adrenal medulla has ACH nicotinic receptor which are ligand-gated Na/k channeles ? muscarinic ACH receptors are G-protein-coupled receptors.

gdupgrant  epinephrine acts on alpha or beta adrenergic receptors which are all G protien receptors. muscarinic receptors are also G coupled but Acetyl choline wasnt an answer choice. In the adrenal medulla the chromaffin cells are kinda like modified post ganglionic neurons and have nicotinic receptors.
... diabetes is asking for clarification on nbme23/block2/q#4 (An 18-year-old woman comes to the physician because...)
 +1  upvote downvote
submitted by diabetes(14)

can somebody explain how energy production by glycolysis increased, since aerobic glycolysis produce 32 net ATP,compare to 2 net ATP through anaerobic glycolysis ?

diabetes  i think the stem should be "energy production by an anaerobic glycolysis "
blueberrymuffinbabey  yeah that's the bit that tripped me up too. i get that there would be increased glycolysis in general to compensate for lack of TCA function but...the fact that it says "energy production by glycolysis" is kind of misleading/confusing.
thotcandy  technically, glycolysis is the reaction that happens in the cytosol that generates pyruvate and 2 net ATP. after that it's TCA and Oxidative phosphorylation, which occur in the mitochondria. By definition, glycolysis is anaerobic - which is why they hammer the fact that RBC undergo glycolysis only into our heads.
thotcandy  technically, glycolysis is the reaction that happens in the cytosol that generates pyruvate and 2 net ATP. after that it's TCA and Oxidative phosphorylation, which occur in the mitochondria. By definition, glycolysis is anaerobic - which is why they hammer the fact that RBC undergo glycolysis only into our heads.
targetmle  i got it wrong because of this as i thought ATP will be decreased in anaerbic glycolysis, but proabably it was mainly 'glycolysis' is increased
... medninja is asking for clarification on nbme15/block2/q#29 (2-month-old male infarct, brought to ER, 2 days generalized tonic-clonic seizures)
 +0  upvote downvote
submitted by medninja(4)

This question sounded like botulism, anybody knows why is tetanus?

... hello36654 is asking for clarification on nbme23/block2/q#16 (Which of the following best explains impaired action...)
 +1  upvote downvote
submitted by hello36654(3)

so why is "cessation of fast axonal transport" wrong? Don't myelinated axons, by definition, have fast conductance? So demyelinated axons would have "cessation of fast axonal transport", which is the answer A, right?

diabetes  i think it slows down ,no cessation .
gdupgrant  Because fast axonal transport refers to the transport of vesicles containing neurotransmitters or some kind of cell product up and down microtubules in the axon. It isn't related to actual electrical signal transduction.
... hello36654 is asking for clarification on nbme23/block2/q#9 (A 60-year-old man has had easy fatigability, loss of...)
 +0  upvote downvote
submitted by hello36654(3)

I understand why it's lung now, but I picked thyroid gland because often times thyroid tumors press on the parathyroid sitting above, which causes the parathyroids to secrete more Ca...can someone comment if they've read this too?

paulkarr  I personally have not read that, but I wouldn't be surprised by that fact. I think with these NBME problems though, if you can get the answer within one "step" that should be your choice. Here you can just go Squamous Cell Carcinoma with a direct action on serum calcium levels (via PTHrP). Thyroid requires a few more steps, (assuming your statement is true) so in the eyes of NBME, it ain't gonna be the right choice. Always follow the "KISS" logic!
... yobo13 is asking for clarification on nbme24/block4/q#3 (A 23-year-old woman is brought to the emergency...)
 +1  upvote downvote
submitted by yobo13(0)

Can someone explain why it can't be Crohn's since that would also cause a non AGMA?

drpatinoire  If she has Crohn, she has already lost a lot of K, HCO3-, then the compensatory system wouldn't let her keep losing electrolytes in her urine.
... elf16 is asking for clarification on nbme22/block2/q#7 (A 66-year-old man comes to the physician because of...)
 +2  upvote downvote
submitted by elf16(2)

How is this different from the question on NBME 21 in which a 68-year old man also had psychogenic ED? But the answer was normal libido and nocturnal erections.

toxoplasmabartonella  In that case, his testosterone was normal and he had no signs of depression. The stem did say his wife passed away few months ago, so i personally chose low libido, but whatever.
... cat5280 is asking for clarification on nbme23/block1/q#37 (A 47-year-old woman with multiple sclerosis is...)
 +1  upvote downvote
submitted by cat5280(1)

Could someone please explain why you were able to eliminate the spinocerebellar tracts?

ergogenic22  Spinocerebellar is only responsible for Proprioception (unconscious). This patient also has reduced vibration sensation, which the dorsal column tracts are responsible for.
... krewfoo99 is asking for clarification on nbme24/block4/q#17 (A 63-year-old woman undergoes operative repair of a...)
 +2  upvote downvote
submitted by krewfoo99(58)

Why would decreased movement through the cerebreal aquaduct be wrong? With all the build of blood in the CSF tract without absorption, wouldnt movement also be decreased through the aqueduct?

ergogenic22  this would cause a non-communicating hydrocephalus with enlarging of the lateral and 3rd ventricles but normal 4th ventricle and subarachnoid space
... defalty98 is asking for clarification on nbme23/block1/q#16 (Physical analysis of the isolated genomic DNA from a...)
 +4  upvote downvote
submitted by defalty98(3)

Why are we complicating things? Change in the bases will destroy the palindromic sequence required for any restriction endonuclease to work. Methylation is the only option that makes sense.

arcanumm  This makes sense have reading what your comment. I overlooked this and just assumed the GATC was a mutation that allowed the restriction enzyme to work on the mutant only.
arcanumm  it makes even more sense when looking at "numerous small fragments." Methylation is truly the obvious answer here in retrospect.
bgiri  DNAse can also cause a change in base by breaking down dna at the GATC sequence?
almondbreeze  @bgiri Had the same reasoning - according to wiki, DNase catalyzes the hydrolytic cleavage of phosphodiester linkages in the DNA backbone, thus degrading DNA.
... jigyasa is asking for clarification on nbme23/block1/q#13 (A researcher is asked to prospectively investigate...)
 +1  upvote downvote
submitted by jigyasa(1)

Why have you taken 180 as patient years? Isn't patient years calculated as no of patients multiplied by the number of years they suffer?

... titanesxvi is asking for clarification on nbme23/block4/q#28 (An 18-month-old girl is brought to the physician...)
 +0  upvote downvote
submitted by titanesxvi(43)

why not decrease CA activity in the proximal tubule? this also could lead to metabolic acidosis.

ergogenic22  carbonic anhydrase inhibitors can cause Type 2 RTA but it is not the cause here (cystinosis)
... krewfoo99 is asking for clarification on nbme23/block1/q#22 (An investigator is studying the adverse effects of a...)
 +1  upvote downvote
submitted by krewfoo99(58)

Why would perforins be the wrong answer? Wouldnt accumulation of toxic proteins cause the cell to undergo apoptosis ?

ergogenic22  Bortezomib does not directly activate perforin. It directly inhibits the proteasome which → enables CD8+ T cells to initiate apoptosis → via perforin release (in essence a downstream effect).
drzed  Exactly, it triggers the cells to undergo apoptosis which means that it can either be cell mediated (perforin and granzyme via FAS/FASL) OR it could also be through the intrinsic pathway (e.g. mitochondrial; cytochrome c)
powerhouseofthecell  Question: But how do CD8 cells have a role in this process exactly in the vignette? Is it saying that when the proteins build up, only then do CD8 cells come and instead of MHC I presenting to proteasomes, they present it to CD8 to initiate apoptosis?
... krewfoo99 is asking for clarification on nbme23/block1/q#33 (A 25-year-old woman and her 25-year-old husband come...)
 +1  upvote downvote
submitted by krewfoo99(58)

In what situations will HbH be formed (3 alpha chain deletions)?

ergogenic22  one parent has 2 deletions on the same gene, the other parent has 1 deletion, and the offspring receives all three. In this question, both parents have alpha 1 deletion
ergogenic22  actually its possible that they both have 2 gene deletions, but regardless, a-thalassemia trait is more likely
ergogenic22  and someone above said Asian people are cis-2 deletion so the offspring will not receive two deletion from one parent
ergogenic22  ↑↑ I made a mistake by confusing trans and cis cis has deletions on the same chromosome and can pass two deletions to off spring, therefore a chance of allowing HbH
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