While still in its prototype phase, the Tensegrity foot is designed to mimic the action of a jointed foot to allow for a more natural and stable gait. Built by inventor and mechanical engineer Jerome Rifkin, the artificial foot bends like a normal foot and ankle, and conforms to the terrain underneath it.

Boston, MA-Scientists at Schepens Eye Research Institute have identified specific molecules in the brain that are responsible for awakening and putting to sleep brain stem cells, which, when activated, can transform into neurons (nerve cells) and repair damaged brain tissue. Their findings are published online this week in the Proceedings of the National Academy of Science (PNAS).

An earlier paper (published in the May issue of Stem Cells) by the same scientists laid the foundation for the PNAS study findings by demonstrating that neural stem cells exist in every part of the brain, but are mostly kept silent by chemical signals from support cells known as astrocytes.

³The findings from both papers should have a far-reaching impact,² says principal investigator, Dr. Dong Feng Chen, who is an associate scientist at Schepens Eye Research Institute and an assistant professor of ophthalmology at Harvard Medical School. Chen believes that tapping the brain¹s dormant, but intrinsic, ability to regenerate itself is the best hope for people suffering from brain-ravaging diseases such as Parkinson¹s or Alzheimer¹s disease or traumatic brain or spinal cord injuries.

A new report shows that a non-ambulatory (unable to walk or stand) child with a cervical spinal cord injury was able to restore basic walking function after intensive locomotor training. The case study, published in Physical Therapy (May 2008), the scientific journal of the American Physical Therapy Association (APTA), evaluated the effects of locomotor training in a 4 ½ year-old-boy, who had no ability to walk following a gunshot wound sixteen months earlier.

Researchers have uncovered a completely unexpected way that the brain repairs nerve damage, wherein cells known as astrocytes deliver a protective protein to nearby neurons.

While the ability of astrocytes to produce MT has been known for decades, the general view was that the MT stayed within astrocytes to protect them while they help repair damaged areas. However, Chung and colleagues demonstrated that MT was present in the external fluid of damaged rat brain. Furthermore, with the aid of a fluorescent MT protein, they observed that MT made in astrocytes could be transported outside the cell and then subsequently taken up by nearby nerves, and that the level of MT uptake correlated with how well the nerves repaired damage.

PITTSBURGH, May 28 – A monkey has successfully fed itself with fluid, well-controlled movements of a human-like robotic arm by using only signals from its brain, researchers from the University of Pittsburgh School of Medicine report in the journal Nature. This significant advance could benefit development of prosthetics for people with spinal cord injuries and those with “locked-in” conditions such as Lou Gehrig’s disease, or amyotrophic lateral sclerosis.

“Our immediate goal is to make a prosthetic device for people with total paralysis,” said Andrew Schwartz, Ph.D., senior author and professor of neurobiology at the University of Pittsburgh School of Medicine. “Ultimately, our goal is to better understand brain complexity.”

Previously, work has focused on using brain-machine interfaces to control cursor movements displayed on a computer screen. Monkeys in the Schwartz lab have been trained to command cursor movements with the power of their thoughts.

“Now we are beginning to understand how the brain works using brain-machine interface technology,” said Dr. Schwartz. “The more we understand about the brain, the better we’ll be able to treat a wide range of brain disorders, everything from Parkinson’s disease and paralysis to, eventually, Alzheimer’s disease and perhaps even mental illness.”

Using this technology, monkeys in the Schwartz lab are able to move a robotic arm to feed themselves marshmallows and chunks of fruit while their own arms are restrained. Computer software interprets signals picked up by probes the width of a human hair. The probes are inserted into neuronal pathways in the monkey’s motor cortex, a brain region where voluntary movement originates as electrical impulses. The neurons’ collective activity is then evaluated using software programmed with a mathematic algorithm and then sent to the arm, which carries out the actions the monkey intended to perform with its own limb. Movements are fluid and natural, and evidence shows that the monkeys come to regard the robotic device as part of their own bodies.

The primary motor cortex, a part of the brain that controls movement, has thousands of nerve cells, called neurons, which fire together as they contribute to the generation of movement. Because of the massive number of neurons that fire at the same time to control even the simplest of actions, it would be impossible to create probes that capture the firing pattern of each. Pitt researchers developed a special algorithm that uses limited information from about 100 neurons to fill in the missing signals.

“In our research, we’ve demonstrated a higher level of precision, skill and learning,” explained Dr. Schwartz. “The monkey learns by first observing the movement, which activates his brain cells as if he were doing it. It’s a lot like sports training, where trainers have athletes first imagine that they are performing the movements they desire.”

The need for better prosthetics, driven in part by the hundreds of amputees returning from Iraq and Afghanistan, has spurred a host of innovations enabling unprecedented control over artificial arms and legs. Already, researchers have begun unveiling sensor and microprocessor-packed “intelligent” knees, thought-controlled mechanical arms, and artificial hands with fingers able to pinch and grab.

Technology is being developed to allow people with severe motor disabilities to play 3D computer games like World of Warcraft using only their eyes.

Since the 1990s, gaze technology has helped people with conditions such as motor neurone disease (MND), cerebral palsy and other “locked-in syndromes” to control 2D desktop environments and communicate using visual keyboards.

Users typically guide a cursor with their eyes, staring at objects for a time to emulate a mouse click.

Eye-gaze systems bounce infrared light from LEDs at the bottom of a computer monitor and track a person’s eye movements using stereo infrared cameras. This setup can calculate where on a screen the user is looking with an accuracy of about 5 mm.

Vickers’ software includes the traditional point and click interface, but includes extra functions to speed up certain commands.

Glancing momentarily off-screen in a particular direction switches between different functions, for example, to a mode that rotates the avatar or viewpoint, or to call up transparent icons dragged onto game objects to perform a particular action.

A “gaze gesture” is also built in to temporarily turn off the eye-gaze functions altogether, to avoid unintentionally selecting an item while looking around the screen.

Vickers hopes to begin trials of the software with people with locked-in syndrome within the next year.

A paper on the new system was presented at the Eye Tracking Research & Applications Symposium 2008 in Savannah, US.

In every town in every part of this sprawling country you can find a faceless sprawling strip mall in which to do the shopping. Rarely though would you expect to find a medical miracle working behind the counter of the mall’s hobby shop.

That however is what Lee Spievak considers himself to be.

“I put my finger in,” Mr Spievak says, pointing towards the propeller of a model airplane, “and that’s when I sliced my finger off.”

It took the end right off, down to the bone, about half an inch.

The photos of his severed finger tip are pretty graphic. You can understand why doctors said he’d lost it for good.

Today though, you wouldn’t know it. Mr Spievak, who is 69 years old, shows off his finger, and it’s all there, tissue, nerves, nail, skin, even his finger print.

How? Well that’s the truly remarkable part. It wasn’t a transplant. Mr Spievak re-grew his finger tip. He used a powder - or pixie dust as he sometimes refers to it while telling his story.

Mr Speivak’s brother Alan - who was working in the field of regenerative medicine - sent him the powder.

For ten days Mr Spievak put a little on his finger.

“The second time I put it on I already could see growth. Each day it was up further. Finally it closed up and was a finger.

“It took about four weeks before it was sealed.”

Now he says he has “complete feeling, complete movement.”

The “pixie dust” comes from the University of Pittsburgh, though in the lab Dr Stephen Badylak prefers to call it extra cellular matrix.

Research on traumatic spinal cord injuries is hampered by a reliance on animal experiments that don’t accurately predict human outcomes, says a new study in the upcoming edition of the peer-reviewed journal Reviews in the Neurosciences. The review was written by scientists with the Physicians Committee for Responsible Medicine.

“Despite decades of animal experiments, we still don’t have a drug to cure spinal cord injury in humans,” says Aysha Akhtar, a neurologist with PCRM and the lead author. “According to the Journal of the American Paraplegic Society, at least 22 agents were found to improve spinal cord injury in animals, but not one of these was helpful in humans,” says Dr. Akhtar.

MONDAY, April 28 (HealthDay News) — Patients having decompression surgery within 24 hours of a cervical spinal cord injury may have a better outcome than those who have the procedure later, according to new research.

Surgical decompression of the spinal cord involves the removal of various tissue or bone fragments that are being squeezed and comprising the spinal cord. While commonly done after an injury occurs, the timing of the procedure varies widely.

The study looked at 170 patients with cervical spinal cord injuries, graded as A (most several neurological involvement) to D (least severe), who underwent decompression surgery.

Six months after the surgery, 24 percent of the patients who had the surgery within 24 hours showed two-grade or greater improvement in their condition compared with only 4 percent in the group that had the surgery more than a day later.