Billy Step 1 Questions # 68 - USMLE Forums
USMLE Forums Logo
USMLE Forums         Your Reliable USMLE Online Community     Members     Posts
Home
USMLE Articles
USMLE News
USMLE Polls
USMLE Books
USMLE Apps
Go Back   USMLE Forums > USMLE Step 1 Forum

USMLE Step 1 Forum USMLE Step 1 Discussion Forum: Let's talk about anything related to USMLE Step 1 exam


Reply
 
Thread Tools Search this Thread Display Modes
  #1  
Old 11-01-2012
billy's Avatar
USMLE Forums Guru
 
Steps History: Not yet
Posts: 444
Threads: 109
Thanked 370 Times in 208 Posts
Reputation: 380
Arrow Billy Step 1 Questions # 68

1-30. A 45-year-old male is hospitalized for treatment of myocardial infarction. His father and a paternal uncle also had heart attacks at an early age. His cholesterol is elevated, and lipoprotein electrophoresis demonstrates
an abnormally high ratio of low- to high-density lipoproteins (LDL to HDL). Which of the following is the most likely explanation for this problem?


a. Mutant HDL is not responding to high cholesterol levels
b. Mutant LDL is not responding to high cholesterol levels
c. Mutant caveolae proteins are not responding to high cholesterol levels
d. Mutant LDL receptors are deficient in cholesterol uptake
e. Intracellular cholesterol is increasing the number of LDL receptors
Reply With Quote Quick reply to this message
The above post was thanked by:
lildoctor88 (11-01-2012)



  #2  
Old 11-01-2012
blade's Avatar
USMLE Forums Guru
 
Steps History: 1+CK+CS+3
Posts: 358
Threads: 22
Thanked 204 Times in 116 Posts
Reputation: 214
Default DD

DD...familiar hypercholesterolemia
__________________
with God,nothing is impossible...PREMATCHED!!!
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Reply With Quote Quick reply to this message
  #3  
Old 11-01-2012
trupti's Avatar
USMLE Forums Scout
 
Steps History: Not yet
Posts: 75
Threads: 3
Thanked 45 Times in 21 Posts
Reputation: 55
Default

D) Mutant LDL receptor are deficient in cholesterol uptake..early age cardiac probs with family history,lab findings s/o familial hypercholesterolemia..mutant LDL receptors(mainly on hepatocytes)-reduced uptake of cholesterol containing IDL & LDL PARTICLES from circulation-raised LDL
Reply With Quote Quick reply to this message
 
  #4  
Old 11-01-2012
venky2600's Avatar
USMLE Forums Master
 
Steps History: 1+CK+CS+3
Posts: 1,186
Threads: 119
Thanked 822 Times in 434 Posts
Reputation: 832
Send a message via Yahoo to venky2600
Post

D) familial hypercholesterolemia........
thanks
Reply With Quote Quick reply to this message
  #5  
Old 11-01-2012
rupesh's Avatar
USMLE Forums Guru
 
Steps History: 1 + CS
Posts: 386
Threads: 71
Thanked 193 Times in 109 Posts
Reputation: 203
Send a message via AIM to rupesh
Default

Type 2 hypercholesterolemia>>>>ldl receptor defect
Reply With Quote Quick reply to this message
  #6  
Old 11-02-2012
billy's Avatar
USMLE Forums Guru
 
Steps History: Not yet
Posts: 444
Threads: 109
Thanked 370 Times in 208 Posts
Reputation: 380
Correct Answer D is correct

This man has familial hypercholesterolemia , an autosomal dominant phenotype defined by studying men who experienced heart attacks at young ages. Mutations in the LDL receptor lead to decreased cellular cholesterol uptake and increased serum cholesterol. Since LDL has a high cholesterol content, the LDL fraction is elevated compared to the HDL fraction on lipoprotein electrophoresis. In normal individuals, the LDL is taken up by its specific receptor and imported via caveolae to the cell interior. Cholesterol then produces feedback inhibition on the rate-limiting enzyme of cholesterol synthesis (hydroxymethylglutaryl CoA reductase) and also leads to a decrease in the number of LDL receptors. In rare cases, two individuals with familial hypercholesterolemia marry and produce a child with homozygous familial hypercholesterolemia. These children develop severe atherosclerosis and xanthomas (fatty tumors) at an early age.
Reply With Quote Quick reply to this message
The above post was thanked by:
mayankkaushal (02-12-2013), MiSeRy (11-02-2012), subbi (11-02-2012)



Reply

Tags
Biochemistry-, Pathology-, Step-1-Questions

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the USMLE Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:
Medical School
Choose "---" if you don't want to tell. AMG for US & Canadian medical schools. IMG for all other medical schools.
USMLE Steps History
What steps finished! Example: 1+CK+CS+3 = Passed Step 1, Step 2 CK, Step 2 CS, and Step 3.

Choose "---" if you don't want to tell.

Favorite USMLE Books
What USMLE books you really think are useful. Leave blank if you don't want to tell.
Location
Where you live. Leave blank if you don't want to tell.

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes


Similar Threads
Thread Thread Starter Forum Replies Last Post
Billy Step 1 Questions # 65 billy USMLE Step 1 Forum 6 10-31-2012 11:35 AM
Billy Step 1 Questions # 59 billy USMLE Step 1 Forum 8 10-31-2012 02:27 AM
Billy Step 1 Questions # 17 billy USMLE Step 1 Forum 9 10-09-2012 11:19 AM
Billy Step 1 Questions # 15 billy USMLE Step 1 Forum 8 10-09-2012 11:15 AM
Billy Step 1 Questions # 16 billy USMLE Step 1 Forum 9 10-09-2012 09:55 AM

RSS Feed
Find Us on Facebook
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.

USMLE® & other trade marks belong to their respective owners, read full disclaimer
USMLE Forums created under Creative Commons 3.0 License. (2009-2014)