Here are some of the latest health and medical news developments, compiled by the editors of HealthDay:
Scientists Trying to Grow Limbs in Laboratory
Scientists are experimenting with monkey arms to test whether it's possible to create new limbs for people in the laboratory.
First, the team strips a monkey arm down as far as its basic cells, leaving behind a bare scaffold. They then use infusions of cells from other individuals in order to grow and transform the limb, CNN reported.
The goal is to create a fully functional limb that has the blood, bones, muscles and cartilage of the individual that provided the new cells, thereby reducing the risk that it will be attacked by that individual's immune system after transplant.
The work is being led by Harald Ott, director of the organ repair and regeneration lab at Massachusetts General Hospital.
If this approach proves successful, "you could regenerate ... on demand," Ott told CNN.
So far, he has used this technique to grow lungs and a beating heart in the laboratory. Earlier this year, he regenerated the limb of a rat and is now placing human cells in a monkey arm scaffold in an attempt to create fully functioning blood cells and vessels.
Fatigue a Major Problem for U.S. Air Traffic Controllers
Fatigue is a major problem among air traffic controllers in the United States, affecting their ability to do their job and putting airline passengers at risk, according to a Federal Aviation Administration study.
It found that nearly 20 percent of air traffic controllers made significant errors in the previous year -- such as guiding planes too close to each other -- and that more than half of the controllers blamed the errors on fatigue, the Associated Press reported.
One-third of controllers said fatigue was a "high" or "extreme" safety risk.
More than 60 percent of controllers said that in the previous year they had fallen asleep or had a lapse in attention while driving to or from midnight shifts. Controllers averaged 5.8 hours of sleep per night during the work week, and averaged only 3.1 hours before midnight shifts and 5.4 hours before early morning shifts, the AP reported.
The study included more than 3,200 air traffic controllers who were asked about their sleep habits and work schedules, and more than 200 who underwent sleep and mental alertness monitoring.
The study was completed nearly four years ago, but not released by the FAA. However, the AP obtained a draft of the final report dated Dec. 1, 2011.