Tuesday, July 02, 2013

Crabtree and cardiovascular surgery

Just a brief update as it appears to relate to the last post on the problems of acute normoglycaemia, via Heartwire.

Sudden onset attempted normoglycaemia is not a good idea 48 hours before cardiovascular surgery.

Hard to say whether the strokes might be associated with exposing the Crabtree effect (mothballed mitochondria) or the risks of letting a surgeon loose with a bottle of insulin and a low fat diet, ie blood glucose <40mmol!

Peter

10 comments:

O Numnos said...

Or could it be insulins effect on vascular/SNS tone?

Just my first thought. No opinions worth squat.

Peter said...

Glucose/insulin/potassium seem to be beneficial or neutral, depending on your bias, for management of acute coronary syndrome. The more I think about it the more the hypos might matter... Dunno, just caught my eye!

Peter

Ken said...

Peter,
If you have not seen it, you might be interested in recent Science Mag. research paper referenced here:
http://www.sciencedaily.com/releases/2013/06/130613161833.htm
(taken from Jenny Ruhl's blog)
Jenny's comments:
http://diabetesupdate.blogspot.com/
"A major study published in the journal Science explains why our understanding of how mitochondria works has been wrong......"

Michael Sheldrick said...

Here's the link from the study that suggests our "understanding of how mitochondria works has been wrong..." is actually here:
http://www.sciencedaily.com/releases/2013/06/130627142404.htm

Of additional interest, they say the following:

"During the study the team also made the unexpected discovery that the most widely used mouse strain for laboratory genetic analysis is unable to correctly assemble the respiratory supercomplexes. This raises serious questions about the validity of extrapolating results obtained with these mice to humans."

What, we have to throw everything out?

MikeS

skepticle said...

Hi Peter, I'm curious to know your opinion on Xylitol. This article http://www.laleva.cc/food/xylitol.html mentions it's benefit for the teeth a lot but I am weary to believe some of it's claims about being lower carb. Much appreciated!

Purposelessness said...

Reading material for the mitochondriacs :)

Turnstiles and bifurcators: The disequilibrium converting engines that put metabolism on the road

► A model for the origin of life is discussed in thermodynamic and geochemical terms. ► Its geochemical basis is the alkaline vent, serpentinization, Hadean ocean model. ► Its thermodynamic approach is framed in terms of non-equilibrium thermodynamics. ► It emphasizes processes of free energy conversion and their mechanistic requirements. ► Living systems are seen as a network of disequilibria linked in driver–driven pairs.

http://www.sciencedirect.com/science/article/pii/S0005272812010420

Evangelista Nick said...

Sounds scary!

Peter said...

Hi Ken and Michael,

The next question is whether B56 mice have been bred to have, already in situ, the defect in their mitochondria which is first in line to occur as a result of hyperglycaemia, which would make obesity research based on these mutant mice core to understanding obesity in humans!!!!! I don't really think this IRL, but boy, would it be funny of it were true. As funny as if adding two herbs to your boiled spuds rendered them obesogenic when one didn't! Not holding my breath, but great links

Peter

Peter said...

Purp,

Have you been to Nick Lane's publications list? He's just hosted a meeting at the Royal Society and two major summary papers are there for download as pdfs on this subject. Also interesting re Mars and Curiosity and origins of life. If there were alkaline vents on Mars with a CO2 atmosphere there will be life deep in the rock. The bulk of the Earth's biomass (in kg) is autotrophic bacteria in the first mile deep of the crust...

Peter

Peter said...

Hi skepticle,

I've never indulged that I'm aware of, so no comment really. It's been a long time since we included any sort of sweetener other than sucrose or honey within carb limits that I've no experience. One problem of sustained LC is that pretty much everything vegetable has a hint of sugar in it's flavour. Even turnips. Pasnips more so, sweet potatoes are OTT for sweetness...