Replacing teeth and white blood cells, and a wi-fi enabled pacemaker.

Aug 30, 2009

I realize that some of these stories are kind of old, but in my defense I work a lot.

Scientists at the Tokyo University of Science announced earlier this month that they had grown a replacement tooth for an adult lab mouse. While this doesn’t sound like much given that rodent teeth grow continually through the creature’s life, they accomplished this task by engineering mouse cells to grow teeth and transplanting them into the socket of an extracted tooth. The tooth grown was fully functional, and seemed to have all of the nerve connections, structural integrity, and usability of a natural mouse tooth. While the paper published in PNAS talks about the potentials for organ regeneration, my ideas for it don’t fall too far from the tree they grew on, given my generally lousy dental history. A commented on Slashdot pointed out a few weeks ago that if you’re already genetically predisposed toward having bad teeth this won’t help you a whole lot in the long run, but I’d like to point out that having good teeth for another thirty or forty years goes a long way toward having a decent quality of life.

A major problem involved in the development of new pharmaceuticals is toxicity insofar as the subsystem of the human body which constructs new blood cells is concerned. It isn’t all that easy to develop a drug that doesn’t impact the productin of new red blood cells (which are replaced about every 110 days, give or take) or white blood cells (which are semi-autonomous, which complicates matters even further due to their complexity). Researchers at the University of Wisconsin at Madison have figured out how to use stem cells to produce blood cells. Specifically, they figured out how to use embryonic stem cells as well as re-embryonized adult cells (cells that have been converted back into stem cells) to produce a number of varieties of white blood cells, which are often the first to be impacted by long-term drug therapy, such as that required by cancer. The most immediate application of this technique would involve testing new drugs in vitro to determine toxic serum concentrations, but it is thought that some time down the line hematopoetic cells (stem cells which only produce blood cells) could be created in a laboratory, the better to be used in lieu of bone marrow transplants. Biocompatibility problems could be licked once and for all by using the patient’s own cells for this procedure.

One final article that I really should have written about earlier, the world’s first wi-fi enabled pacemaker is now in field testing. The implanted device, which not only regulates the user’s cardiac rhythms but keeps detailed records for analysis by a cardiologist offline was implanted in one Carol Kasyjanski at Saint Francis Hospital in Roslyn, New York in mid-July of 2009 after the FDA signed off on its clinical use in humans. The pacemaker communicates with a wireless access point installed in Kasyjanski’s home and uploads its cache of status information at least once a day for analysis. If anything is amiss, her cardiologist will be alerted at any time of day.