University of Alberta researcher Vivian Mushahwar with Smart-e-Pants
We often speak of the luxury of sinking into bed, but if you really sank in, and couldn’t get back up, things would go badly for you. People immobilized by neurological injuries often develop nasty wounds called bedsores, which form when soft tissues, such as the buttocks, heels, and back of the head, get pressed against the surface of a bed or wheelchair so that the tissue’s oxygen supply is cut off and it starts to die. The resulting open wounds can penetrate all the way down to muscle and bone and are often infected. Bedsores, unfortunately, affect 25 percent of nursing home residents, 10 percent of hospital patients and 60 percent of quadriplegics.
A group of Canadian researchers has looked to underwear for a potential solution. They’ve developed underpants implanted with electrodes that periodically (and painlessly) shock the gluteal muscles. The muscles contract slightly, much the same way they do when people fidget unconsciously, and relieve the pressure on tissues to give them the gasp of oxygen that they need. The team calls the invention Smart-e-Pants.
Although the spinal cord can recover from minor damage, severe injuries, like those that cause paralysis, are permanent…right? When deep cuts partially sever rats’ spinal cords, they isolate the lower part of the spine from the brain. Since that part of the spine is responsible for controlling the rats’ hind limbs, it leaves the legs paralyzed. A team of Swiss scientists tackled the challenge of restoring the brain-to-limb connection, successfully re-teaching paraplegic rats to walk, run, and climb stairs.
First, the researchers injected the isolated section of spinal cord with neuron-exciting chemicals called neurotransmitters. Then, they used electrodes on the outside of the spinal cord to send continuous electrical signals to those excited nerve cells. This chemical and electrical stimulation acted as a sort of molecular prosthesis for the signals that would normally come from the brain but that couldn’t get past the spinal injury.
For more than a decade, Geron has been a pillar of human embryonic stem cell research. They were the first to embark on embryonic stem cell trials, with a treatment for patients with spinal cord injury last year. They also have the distinction of having funded the research that isolated the first human embryonic stem cells, way back in 1998. But the company has just announced that they will be shuttering the stem cell portion of their operation.
Their spinal cord trial to assess whether a low dose of cells in a newly injured spine is safe, which had enrolled four patients, had been progressing as expected, so it’s not that they’ve lost faith in the science. It’s all about the money: Geron has two cancer drugs in clinical trials, and according to their announcement, this was the only way to continue supporting that research without having to raise more funds. They’ll be laying off 38% of their employees as a result of the decision. The four patients will continue to be monitored.
Yes, it’s a milestone. The first federally approved trial of an embryonic stem cell therapy has begun, and the first patient with a spinal cord injury has been injected with a treatment made from embryonic stem cells. But if all goes well with the trial, conducted by the biotech company Geron, there won’t be any dramatic results–the trial is simply intended to test the treatment’s safety, and patients will receive very low doses of the stem cell concoction.
The patient, whose name was not disclosed, is enrolled at the Shepherd Center, a rehabilitation center in Atlanta; the company has said it plans to enroll 8 to 10 patients in the study at sites around the country. Even if all goes well in the early-stage study, the treatment faces many years of testing for effectiveness before it could be approved as a therapy for spinal injuries. [New York Times]
For the trial, which gained final approval in August, Geron is working with a technique pioneered by the neurobiologist Hans Keirstead, who licensed the technology to Geron.
Hugging someone standing up. Going on a hike. Making eye contact with someone at their level, instead of always being looked down upon. These are simple things that people stuck in wheelchairs don’t have a chance to experience in daily life.
Berkeley Bionics is giving those experiences back to paraplegics with the introduction of an exoskeleton suit called eLEGS–a battery powered, artificially intelligent, wearable outer skeleton that gives these people back their freedom. People wearing these devices won’t be a common sight just yet–a suit is currently priced at about $100,000 a pop, and they’ll only be available for use in clinics at first–but it’s an exciting step forward.
The person straps into an exoskeleton made of carbon fiber and steel, which weighs 45 pounds. Sensors in the legs convey their position to a control unit contained in a backpack, and the controller tells which joints to bend to create a natural gait. The user gives the suit commands using two high-tech crutches: pressure on both tells the motorized legs to stand up, pressure on one means to step with the opposite leg. The suit’s battery pack can power up to six hours of walking, and it can reach speeds above two miles per hour.
Amanda Boxtel, who was paralyzed from the waist down in a skiing accident 18 years ago, tried out the device and says she took to it quickly.
“Walking with eLEGs took some rewiring and relearning,” says Boxtel, “but my body has the muscle memory. And I learned to walk really fast.” [New Scientist]
The suit will be used in a clinical trials at select rehabilitation centers starting in early 2011, and its makers hope a commercial model won’t be too far behind. Berkeley Bionics wants to make a lighter, thinner, and cheaper model (hopefully closer to $50,000, Berkeley Bionics CEO Eythor Bender says) available for home use by 2013.
Hit the jump for more info, and a poignant video of several paralyzed people giving eLEGS a tryout.
Scientists recently used treadmill exercise, drugs, and electrical stimulation to train paralyzed rats to walk once again, demonstrating a way to possibly treat spinal injuries in humans, which at present are basically untreatable.
In a spinal injury, the neural circuits connecting the brain to the muscles that control walking become damaged or severed, leaving an individual paralyzed. In able-bodied people, these “walking circuits” spring into action when they receive a signal from the brain, but if the spinal cord is damaged, the message from the brain never arrives. When contact with the brain is lost, the circuits shut down [The Guardian]. In the study, published in Nature Neuroscience, researchers manipulated these circuits and produced movement that was “almost indistinguishable” from normal walking. See for yourself in the embedded video.
A chemical compound similar to the blue food dye found in blue M&Ms and blue Gatorade could one day be used to treat people with spinal injuries, and could reduce damage and improve mobility, according to a new study. Researchers found that when they injected the compound Brilliant Blue G (BBG) into rats suffering spinal cord injuries, the rodents were able to walk again, albeit with a limp. The only side effect was that the treated mice temporarily turned blue [CNN].
The same research team had previously shown that ATP, a vital energy source that keeps the body’s cells alive, quickly pours into the area surrounding a spinal cord injury after it occurs. Unfortunately, the release of ATP at hundreds of times the normal level kills off healthy, uninjured motor neuron cells by flooding them with a deluge of molecular signals, making the initial injury worse [BBC News]. In the new experiment, described in the Proceedings of the National Academy of Sciences, the blue compound prevented ATP from latching on to the motor neuron cells, and therefore prevented the secondary damage that occurs in the hours after a spine injury.
In a new study, researchers attached electrodes to individual neurons in monkeys’ brains and then rerouted those neuronal signals through a brain-machine interface, which converted them into electrical signals that controlled the monkeys’ own paralyzed muscles. Researchers say this roundabout feat of bioengineering could eventually lead to new treatments and prosthetics for paralyzed people.
The implant exploits the fact that even when the neural connection between a brain region and the muscles it controls is severed or damaged by, say, a stroke or spinal injury, the controlling neurons remain active. For example, people living with quadriplegia who try to move their arm still generate arm-movement signals in the motor cortex of their brain, even after several years of paralysis [New Scientist]. The new study is the first to send the signals back to the user’s own muscles, as opposed to related research in which the signals are fed into electronic devices.
A man who was paralyzed below the waist 20 years ago is walking again, thanks to a robotic “exoskeleton” that moves his legs and can even navigate up and down hills. The inventors of the device, dubbed the ReWalk, say the experimental technology can give paraplegics a psychological boost through renewed mobility, and can also help people avoid medical problems caused by long-term wheelchair use.
One of the first paraplegics to test out the device is Radi Kaiof, a former Israeli paratrooper who has been paralysed for the last 20 years following an injury during his service in the Israeli military. He says the device has changed his life. “I never dreamed I would walk again. After I was wounded, I forgot what it’s like. Only when standing up can I feel how tall I really am and speak to people eye to eye, not from below” [BBC News].