A few damn tricky questions

[ChoroidPlexus]

What effect would an uncoupling agent have on carbon dioxide and ATP expenditure?

A pregnant woman with an uncpmplicated pregnancy has the appearance of paradoxical hypertension 6 weeks after her pregnancy. What lab test would you use to diagnose the cause of the hypertension?

An old man collapses in a restaurant and goes into V-fib, but then is stabilized with a BP of 90/60. No murmurs or S1, 2, or 4 heard. What is the cause of his ventricular fibrillation?

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[ChoroidPlexus]

Where would two alleles have to be located, as in close to or far away from each other, to have linkage of 50/50?

 

[02115]

Wikipedia:

the greater the distance between linked genes, the greater the chance that non-sister chromatids would cross over in the region between the genes. By working out the number of recombinants it is possible to obtain a measure for the distance between the genes. This distance is called a genetic map unit (m.u.), or a centimorgan and is defined as the distance between genes for which one product of meiosis in 100 is recombinant. A recombinant frequency (RF) of 1 % is equivalent to 1 m.u. A linkage map is created by finding the map distances between a number of traits that are present on the same chromosome, ideally avoiding having significant gaps between traits to avoid the inaccuracies that will occur due to the possibility of multiple recombination events.

 

[ChoroidPlexus]

But I thought the max RF was 50%, so in other words, an RF of 50 would imply that the genes are on the opposite ends of the chromosomes?

 

[xjacob]

Yep, the max you can get is 50%. But that doesn't mean that that if you have 50% frequency, the two loci are "as far as possible." They are just "really far" (or even on a different chromosome).
This is not to say you can't get things that are, say, 60cM apart. You just need to find a gene that's inbetween, and add up the distance. E.g. if A and C recombine 50% of the time, you know they are 50 OR MORE cM apart. If a gene B is 20cM away from A and 40cM from C, then A is 60cM apart from C. This is a very brute force, simplistic approximation, but it might be useful...I might be wrong...

 

[Idiopathic]

I was thinking hemopericardium secondary to aortic arch rupture??? I agree that all other signs point to AAA, but the ascending aortic dissection is really throwing me towards hemop.

The pressure is key. The end result looks to be that the px blew out her arch with 220+ systolic. Upper thoracic chest pain and AI are the keys.

 

[Idiopathic]

Would a cervical uterine cancer or ovarian cancer compress the ureters and cause hydronephrosis?

Yes, invasive cervical CA (actually AIDS-defining lesion nowadays) will do this. Ovarian has the potential also.

The fact that the renal pelvis/calyces are dilated seems to speak towards hydro, regardless of the other info.