CARDIOLOGY: How the Heart Hardens
Surgical medicine has mastered heart valve replacement. Nearly 20,000 people each year undergo the procedure, most commonly due to valve calcification. In this condition, the soft tissue of the heart valves turns slowly into bone, increasing the risk of heart attack. New work from HMS researchers led by Elena Aikawa now suggests that many of these complications may be preventable. In the April 7 Circulation, the team reports detection of the very earliest signs that calcification is imminent. The investigation may lead to novel treatments for preventing heart damage, reducing the need for surgery.

GENOMICS: Personal Risk Prediction: Not There Yet
Personal genome scans and individual risk tests are becoming inexpensive and widely available. The newly identified genetic markers associated with common diseases are a biology bonanza, but they are not yet effective at predicting the medica0l destiny of individuals, say David Hunter (left), Peter Kraft and other Harvard researchers who helped bring about this convergence of science, technology, and popular interest in personal genomics. More powerful indicators of disease and inheritance await discovery in the details of those personal genomes.

NEUROLOGY: Chemical Tag May Be Ticket Out of Town for Huntington’s
Researchers at HMS, including Dimitri Krainc, have found that neurons are able to clean away part of the mess that triggers Huntington’s disease. The gene that causes this incurable brain disorder produces a mutant protein that clutters brain cells. In the April 3 Cell, the team reports on a chemical change that helps neurons sweep away part of the problem using their own cleaning machinery. This natural mechanism may not be enough to block Huntington’s progression, but researchers think they might be able to enhance it, giving neurons an extra edge against the disease.

REGENERATIVE MEDICINE: Homeward Bound
Cancer patients who undergo aggressive chemotherapy or radiation treatment often sustain severe damage to their bone marrow, which may require a bone marrow transplant to rescue the patients from death. The marrow contains blood stem cells that can reconstitute every different type of blood cell in the body, compensating for the damage. Yet this process is inefficient. Blood stem cells that are transplanted, like hematopoietic stem cells from the body, must home to the bone marrow to survive and properly function. Since only a small number manage to do this, large numbers of donor cells must be harvested and infused into the patient’s bloodstream. In a paper published online March 25 in Nature, David Scadden and colleagues identify a key mechanism by which blood stem cells in the circulation navigate to the marrow, a discovery that may lead to increased efficiency in blood stem cell transplantation and greater transplant success.

Copyright 2009 by the President and Fellows of Harvard College