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Old 12-13-2011
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Question About microbiology and other demons II

A 25 years old male that was admitted into the Hospital due to a serious car accident has urinary frequency and dysuria. The rest of his history is unremarkable. Which one of the next would be one of the characteristics of the pathogen that is causing this symptoms?

a. Oxidase positive
b. Oxidase negative
c. Inactivation of the 60S ribosomal subunit
d. Urease-positive
e. Non-movil

The patient is diagnosed, and after been treated with the recommended antibioticotherapy the symptoms cease. The main mechanism of action by which the pathogen was killed is:


a. Purine synthesis inhibition
b. Breaking of bacterial DNA structure
c. Inhibition of transpeptidation of D-alanin
d. Depolarization of membrane potential
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  #2  
Old 12-13-2011
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I think it is s.saprophyticus.

so, it might be d, c
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Old 12-13-2011
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i dont know i hope to hear the answer soon
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Old 12-13-2011
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Default E.coli

I think the most common organism to cause UTI in hospital or any other setting is E.coli now EHEC cause inactivation of 60s ribosomal subunit and DOC for it is is Floroquinolone like ciprofloxacin which is DNA gyrase inhibitor.
So I will go with C and B
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Old 12-14-2011
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Correct Answer Answer...

Quote:
Originally Posted by mohitkmc View Post
I think the most common organism to cause UTI in hospital or any other setting is E.coli now EHEC cause inactivation of 60s ribosomal subunit and DOC for it is is Floroquinolone like ciprofloxacin which is DNA gyrase inhibitor.
So I will go with C and B
Yeap... The most probable bacteria that is causing the infection in first question is E. Coli... almost 80% of the UTIs are due to this germ. It has a shiga-like toxin called verotoxin that inactivates the 60S ribosomal subunit, resulting in protein synthesis inhibition. Risk factor in this case: a foley catheter. Why? After a serious car accident, he might have broken his femur or pelvis; a foley catheter would be an indication of such case.

Question number two... Yeap, intravenous fluoroquinolones (b) are the first line treatment in nosocomial UTIs, they inhibit DNA gyrase (topoisomerase II) leading to the breakage of bacterial DNA. Trimethoprim-sulfamethoxazole (a) is an indication for out-patients, the mechanism of action is the inhibition of the synthesis of TH4, thus, inhibiting purines synthesis in the bacteria.

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Old 12-14-2011
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wer r tes q from?
__________________
if ur ready to learn......world is ready to teach...take d leap!!
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  #7  
Old 12-14-2011
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Default Mmm...

Quote:
Originally Posted by doxorubicin View Post
wer r tes q from?
From nowhere, or... I think that the correct answer will be "me"

I made them up I just try to follow the "two-step answer pattern" like in UW, Kaplan, or the rest of the Qbanks. All is based on FA or other books that I'm reading for step 1, you know... Kaplan, CMMRS, HY... ect, ect.

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