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Some Confusing Questions about Nitropresside and Framshift mutations

3108 Views 7 Replies 3 Participants Last post by  step1an
I have some questions/differentials that are confusing me. I hope somebody could shed some light on them.

  1. Nitroprusside infusion can cause cyanide toxicity (ttt is Na thiosulfate). It can also cause methemoglobinemia (ttt is IV methylene blue and cyanide(?). Is this correct? Can somebody explain this.
  2. In frameshift mutation, there's deletion of a number not divisible by 3 of bases or nucleotides?
  3. How to differentiate between Fibroadenoma and Fibroadensosis (clinically, and by biopsy)?
Thanks in advance.
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[*]In frameshift mutation, there's deletion of a number not divisible by 3 of bases or nucleotides?
Thanks in advance.
I'll just answer this 1 first b/c it will take the least amount of time

Frameshift mutation = nucleotide addition or deletion, when they say not divisible by 3, they just mean that the whole picture moves, if you add or delete 3 then you delete 1 whole gene codon, it wouldn't mess up the rest of the sequence because the rest of those proteins will still be accounted for, however if you add or delete 1 or 2 nucleotides....then you change the whole frame....for example.

when you add or delete 1 or 2 nucleotides, you will have (in this case delete)

now the BBB and BBC per say will not code for the same protein....etc, etc

nucleotide = Base + Sugar + PO4
Base = just the Nucleobase i.e A, T, C, G, U
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I figured out point 1.

Nitrites can cause methemoglobinemia by oxidation of Fe2+ to Fe3+. MetHb is treated with methylene blue.

Surprisingly, this toxicity can also be used as a treatment in cyanide poisoning. MetHb loves CN more than oxygen. So, providing MetHb in CN poisoning will lead to formation of MetHb-CN complexes. At this point, Na thiosulfate is given to bind these complexes and excrete them in the kidneys.
hmmm, maybe I just didn't understand ur question right! but yeah all of this is mentioned in Goljan
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