MIT works toward engineered blood vessels
U.S. scientists have created a technique that induces cells to form parallel tube-like structures that might serve as tiny engineered blood vessels.
Massachusetts Institute of Technology researchers said they found a way to control cell development by growing them on a surface with nanoscale patterning.
The scientists said engineered blood vessels might one day be transplanted into tissues such as the kidneys, liver, heart or any other organs that require large amounts of vascular tissue, which moves nutrients, gases and waste to and from cells.
"We are very excited about this work," said Professor Robert Langer, an author of the study. "It provides a new way to create nano-based systems with what we hope will provide a novel way to someday engineer tissues in the human body."
A paper on the work appeared in the online issue of the journal Advanced Materials.
Tuesday, December 18, 2007
Posted by SANJIDA AFROJ at 10:37 PM
U.S. medical researchers say the cloning of human embryos is still their best hope for developing effective treatments for diseases.
Researchers pursue stem cell technologies
Those opposed to using embryonic stem cells, including President George Bush and some religious leaders, say a new technique for genetically "reprogramming" ordinary adult skin tissue into stem cells could eliminate the need for using human embryos.
At Harvard University, where about 750 lead medical scientists work in 119 laboratories, researchers worry the new technology may never offer help for humans, The Boston Globe reported Monday.
So-called induced pluripotent stem cells, or IPS, made by the skin-cell process may never be safe for humans, some researchers say, the newspaper reported.
"For doing basic research on human cells, IPS as a method has won -- it's huge," said Dr. George Daley, a stem cell researcher at Children's Hospital Boston. "But for the ultimate goal of getting cells into a patient, it's a lot less clear. These cells may never be useful for direct therapy."
Posted by SANJIDA AFROJ at 10:05 PM
Nanofabrication finds new mineral property
U.S. physicists have discovered a new electronic property in lodestone, also known as magnetite -- one of the most studied magnetic minerals on Earth.
Led by Rice University Associate Professor Doug Natelson, the physicists found by changing the voltage in their experiment, they were able to reduce magnetite's temperatures lower than minus 250 degrees Fahrenheit. That resulted in the mineral reverting from an insulator to a conductor.
"It's fascinating that we can still find surprises in a material like magnetite that has been studied for thousands of years," Natelson said. "This kind of finding is really a testament to what's possible now that we can fabricate electronic devices to study materials at the nanoscale."
The magnetic properties of lodestone were documented in China more than 2,000 years ago, and Chinese sailors were navigating with lodestone compasses as early as 900 years ago.
The new research appears in the online edition of the journal Nature Materials and will be published in the journal's February print issue
Posted by SANJIDA AFROJ at 9:20 PM