April 23, 2008

The Ups and Downs of Mechanical Ventilation

Posted in Articles of Interest tagged , , , , , at 10:25 am by D. Borst

So mechanical ventilators are perhaps one of the most important advances in critical care medicine ever. Critically ill patients get too ill to manage their own breathing, and to make sure that their bodies get enough of an air supply, hooking them up to a machine for hours or days has saved countless lives. It has also enabled many invasive surgeries that require the use of drugs that suppress the respiratory drive along with consciousness.

But as with all medical advances, ventilators do come with a cost. When a ventilator is put in, the physician sticks a tube down the patients trachea to make sure that air is going into the patients lungs and not into her stomach. Having a tube stuck down one’s throat precludes much movement, and also slightly abrades the surfaces it comes in contact with. This is postulated to cause the increase in nosocomial, or hospital acquired, infections such as pneumonia.

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Designer Enzymes

Posted in Articles of Interest, Biochemistry tagged , , , at 10:01 am by D. Borst

Harnessing the power of enzymes for commercial reactions is one of the ultimate Holy Grails of synthetic chemistry. It looks like its achievement may have come one step closer. Head on over to Biosingularity for the report on how Kendall Houk of UCLA has begun to make the first successful prototypes of such molecules.

I got to listen to Dr. Houk speak at PSU in February. He is doing some pretty cool organic chemistry intensive stuff, way over my head. But essentially what they did was use quantum mechanical models of the transition state for the reaction they wanted to catalyze, and designed an active site which would stabilize that active site. This is coherent with the transition state stabilization model of enzymatic catalysis. Instead of using amino acids and proteins, they were using complex organic molecules which would do the same things that amino acids would.

This challenge is straightforward, if not simple, in theory. We have the theories to predict all chemical reactions. What we don’t have is the processing power to do the incredibly complex calculations that arise because of the theory. The art of the science is to develop shortcuts and assumptions that will allow one to simplify the calculations to the point where they can be done.

October 22, 2007

Happy 50th to Bone Marrow Transplantation

Posted in Articles of Interest tagged , at 11:25 pm by D. Borst

There was an interesting historical article in the New England Journal of Medicine one and a half weeks ago (ok, Im a little behind, but it comes every week!) about the history of Hematopoietic-Cell Transplantation. It is a story of courage and perseverance of a physician-scientist in the face of confusing data and poor understanding of the biology behind how the body recognizes self from not-self. If you have some time, and you are interested in how things all began, give it a read. Its work that yielded a Nobel Prize. The article is freely available via the NEJM website.