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  #1  
Old 10-18-2012
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Drug Antiviral drug does not require viral kinase?

Which of the following antiviral drug does not require phosphorylation by viral kinase for action..?

a) acyclovir
b) abacavir
c) zidovudine
d) stavudine
e) ganciclovir
f) emtricitabine
g) tenofovir
h) valacyclovir
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  #2  
Old 10-18-2012
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C) Zidovudine

because it is already a nucleotide. Correct?
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Old 10-18-2012
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by exclusion i will go with
Acyclovir, ganciclovir and valacyclovir (prodrug of acyclovir) and all NRTIs require viral kinases. (as i remember)
So my answer I. CIDOFOVIR
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Old 10-18-2012
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Quote:
Originally Posted by venky2600 View Post
Which of the following antiviral drug does not require phosphorylation by viral kinase for action..?

a) acyclovir
b) abacavir
c) zidovudine
d) stavudine
e) ganciclovir
f) emtricitabine
g) tenofovir
h) valacyclovir
@vencky pls post commonly tested drugs,dont be a mean examiner
NNRTIs & foscanet dont need viral kinase phosphorylation but cant find any in your list
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@koolkiller-----answer lies in the given options dude(extra option not gonna need)

@chux---------DIT mentioned it(so thought it as imp.)......also uworld mentioned it in one of it's explanations......
foscarnet and cidofovir are the drugs everyone knows......time to know some extra(everyone can easily answer when the mechanism of the given all drugs is known------------it's high yield..
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Old 10-18-2012
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Quote:
Originally Posted by venky2600 View Post
Which of the following antiviral drug does not require phosphorylation by viral kinase for action..?

a) acyclovir
b) abacavir
c) zidovudine
d) stavudine
e) ganciclovir
f) emtricitabine
g) tenofovir
h) valacyclovir
I think you are thinking of G) Tenofovir, because this was written in the errata for FA 2012. I searched on the internet and I found that the drug needs to be phosphorylated in order to be activated (http://www.fda.gov/ohrms/dockets/ac/..._01_gilead.pdf). All I know it is a nucleotide and not a nucleoside as the rest of the drugs in the NRTIs.
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Quote:
Originally Posted by Teona View Post
I think you are thinking of G) Tenofovir, because this was written in the errata for FA 2012. I searched on the internet and I found that the drug needs to be phosphorylated in order to be activated (http://www.fda.gov/ohrms/dockets/ac/..._01_gilead.pdf). All I know it is a nucleotide and not a nucleoside as the rest of the drugs in the NRTIs.
oh...ya thought about g) tenofovir only......
the only nucleotide RTI.........
actuallly DIT mentioned it as it not requires kinase phosphorylation and also uworld gave in one of it's explanations that 'nucleotide reverse transcriptase inhibitors not need phosphorylation by kinase.....coz nucleotide RTI can act on reverse transcriptase without first being phosphorylated.....'-----Q id---264355

anyways thanks for the info....

i didnt remember that errata has changed it btw...thanks
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Originally Posted by venky2600 View Post
oh...ya thought about g) tenofovir only......
the only nucleotide RTI.........
actuallly DIT mentioned it as it not requires kinase phosphorylation and also uworld gave in one of it's explanations that 'nucleotide reverse transcriptase inhibitors not need phosphorylation by kinase.....coz nucleotide RTI can act on reverse transcriptase without first being phosphorylated.....'-----Q id---264355

anyways thanks for the info....
Well, I guess you are right...if this is mentioned in 3 different sources. I just listened to DIT and it is mentioned only that Tenofovir is a nucleotide, but they don't say anything if it requires phosphorylation or not. But I am not done with DIT...I dont' know what to say.
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Quote:
Originally Posted by Teona View Post
Well, I guess you are right...if this is mentioned in 3 different sources. I just listened to DIT and it is mentioned only that Tenofovir is a nucleotide, but they don't say anything if it requires phosphorylation or not. But I am not done with DIT...I dont' know what to say.
ya..even i didnt complete the entire DIT..it mentioned in one of the quizzes...
i'm thinking that...uworld explanation as true....coz---it gave it can acts on reverse transcriptase before first being phosphorylated(implies phosphorylated later ,it's action not depends on phosphorylation)
it's the way i'm thinking but i'm not sure though
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Originally Posted by venky2600 View Post
oh...ya thought about g) tenofovir only......
the only nucleotide RTI.........
actuallly DIT mentioned it as it not requires kinase phosphorylation and also uworld gave in one of it's explanations that 'nucleotide reverse transcriptase inhibitors not need phosphorylation by kinase.....coz nucleotide RTI can act on reverse transcriptase without first being phosphorylated.....'-----Q id---264355

anyways thanks for the info....

i didnt remember that errata has changed it btw...thanks
vencky i was just joking..i look forward to the answer to learn more but i think you mixed something up or am i wrong?
you said NRTi dont need phosphorylation by T.kinases??i thought it was NNRTI needs no phosphorylation.

2ndly,why did you stop DIT??i stopped too bcos l was learning nothing much from it but i want your skolars input
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Originally Posted by chux View Post
vencky i was just joking..i look forward to the answer to learn more but i think you mixed something up or am i wrong?
you said NRTi dont need phosphorylation by T.kinases??i thought it was NNRTI needs no phosphorylation.

2ndly,why did you stop DIT??i stopped too bcos l was learning nothing much from it but i want your skolars input
haha......i'm not a scholar(i'm just as everyone here ---am a learner)
ya it's NNRTI that dont need phosphorylation( you're right)....and NRTI require phophorylation(nucleoside analogues require it-----nucleotide analogues not require it)....tenofovir is the only nucleotide analogue......
i hope you got a new point...

no i didnt stop doing DIT...(i'm currently doing it,i mean not finished yet-----remaining with cardio,neuro,endocrine and renal)
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  #12  
Old 10-18-2012
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Hey guys isn't it azidovudine. It stops viral replication just because it's an unfit nucleotide and doesn't need any processing by any enzyme.


Sent from my iPad using Tapatalk HD
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Quote:
Originally Posted by drlimerence View Post
Hey guys isn't it azidovudine. It stops viral replication just because it's an unfit nucleotide and doesn't need any processing by any enzyme.


Sent from my iPad using Tapatalk HD
no all nucleoside analogues including zidovudine require phosphorylation to become activated after entering host cell........yes it stops viral replication but after it gets functional by phosphorylation......
hope it understands..thanks
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