NanoTech Restores Vision to Blind Rodents

[Crown]

The Beeb

Nanotech helps blind hamsters see
Nanotechnology has restored the sight of blind rodents, a new study shows.

Scientists mimicked the effect of a traumatic brain injury by severing the optical nerve tract in hamsters, causing the animals to lose vision.

After injecting the hamsters with a solution containing nanoparticles, the nerves re-grew and sight returned.

Writing in the Proceedings of the National Academy of Sciences, the team hopes this technique could be used in future reconstructive brain surgery.

Ultimate challenge

Repairing nerve damage in the central nervous system after injury is seen as the ultimate challenge for neuroscientists, but so far success in this field has been limited.

Nerve regeneration is set back by a number of factors, including scar tissue and gaps in brain tissue caused by the damage. And this can make treatment by medical and surgical methods very difficult.

To find a novel way around these problems, the team based at Massachusetts Institute of Technology (MIT), US, and Hong Kong University looked towards nanotechnology - a branch of science involving the manipulation of atoms and molecules.

The researchers injected the blind hamsters at the site of their injury with a solution containing synthetically made peptides - miniscule molecules measuring just five nanometres long.

Once inside the hamster's brain, the peptides spontaneously arranged into a scaffold-like criss-cross of nanofibres, which bridged the gap between the severed nerves.

The scientists discovered that brain tissue in the hamsters knitted together across the molecular scaffold, while also preventing scar tissue from forming.

Importantly, the newly formed brain tissue enabled the brain nerves to re-grow, restoring vision in the injured hamsters.

"We made a cut, put the material in, and then we looked at the brain over different time points," explained Dr Rutledge Ellis-Behnke, a neuroscientist at MIT and lead author on the paper.

"The first thing we saw was that the brain had started to heal itself in the first 24 hours. We had never seen that before - so that was very surprising."

Stroke repair

The scientists looked at young hamsters with actively growing nerve cells, and also at adults hamsters whose nerves had stopped growing.

Dr Ellis-Behnke said the team was surprised to find that the nerves in the adult hamsters had re-grown after the injection.

"We found that we had got functional return of vision and orientating behaviour, which was very surprising to us because we thought we would have to promote cell growth, through the growth factors."

The researchers found the peptides were later broken down by the body into a harmless substance and excreted in the animals' urine three to four week after first injected.

The scientists believe that they have overcome some of the barriers to nerve regeneration, and hope to be able to apply their work to medical applications at a later stage.

"We are looking at this as a step process. If this can be used while operating on humans to mitigate damage during neurosurgery, that would be the first step," Dr Ellis-Behnke told the BBC News website.

"Eventually what we would look at is trying to reconnect disconnected parts of the brain during stroke and trauma."

Dr Ellis-Behnke said that stroke and traumatic brain injury could have a major impact on an individual.

"In order to try to restore quality of life to those individuals you can try to reconnect some disconnected parts to try to give some functionality in the brain for communication and other things like that. And that's where we think that this might be very useful," he added.

Now this is a promising avenue for nano-tech application. In small, delicate and specialised repairs around the body!

[kheegster]

It'll be a wonderful breakthrough if it can be done to humans (and I don't see why not...at a cellular level we aren't that different from rodents).

But I'll bet the 'oH n0ez t3h nan0tecH 1nVadinG 0uR b0di3Z!!!!111' crowd will start making noise soon....

[dragon]

Now this is a promising avenue for nano-tech application. In small, delicate and specialised repairs around the body!

Yeah there are a few areas where nanotech is coming into play for body repair, such as provinding a scaffod for bone growth. Going to be interesting in a few decades to see what comes of this type of stuff.

Nanotubes inspire new technique for healing broken bones
Scientists have shown for the first time that carbon nanotubes make an ideal scaffold for the growth of bone tissue. The new technique could change the way doctors treat broken bones, allowing them to simply inject a solution of nanotubes into a fracture to promote healing.
The report appears in the June 14 issue of the American Chemical Society's journal Chemistry of Materials. ACS is the world's largest scientific society.

The success of a bone graft depends on the ability of the scaffold to assist the natural healing process. Artificial bone scaffolds have been made from a wide variety of materials, such as polymers or peptide fibers, but they have a number of drawbacks, including low strength and the potential for rejection in the body.

"Compared with these scaffolds, the high mechanical strength, excellent flexibility and low density of carbon nanotubes make them ideal for the production of lightweight, high-strength materials such as bone," says Robert Haddon, Ph.D., a chemist at the University of California, Riverside, and lead author of the paper. Single-walled carbon nanotubes are a naturally occurring form of carbon, like graphite or diamond, where the atoms are arranged like a rolled-up tube of chicken wire. They are among the strongest known materials in the world.

Bone tissue is a natural composite of collagen fibers and hydroxyapatite crystals. Haddon and his coworkers have demonstrated for the first time that nanotubes can mimic the role of collagen as the scaffold for growth of hydroxyapatite in bone.

"This research is particularly notable in the sense that it points the way to a possible new direction for carbon nanotube applications, in the medical treatment of broken bones," says Leonard Interrante, Ph.D., editor of Chemistry of Materials and a professor in the department of chemistry and chemical biology at Rensselaer Polytechnic Institute in Troy, N.Y. "This type of research is an example of how chemistry is being used everyday, world-wide, to develop materials that will improve peoples' lives."

The researchers expect that nanotubes will improve the strength and flexibility of artificial bone materials, leading to a new type of bone graft for fractures that may also be important in the treatment of bone-thinning diseases such as osteoporosis.

In a typical bone graft, bone or synthetic material is shaped by the surgeon to fit the affected area, according to Haddon. Pins or screws then hold the healthy bone to the implanted material. Grafts provide a framework for bones to regenerate and heal, allowing bone cells to weave into the porous structure of the implant, which supports the new tissue as it grows to connect fractured bone segments.

The new technique may someday give doctors the ability to inject a solution of nanotubes into a bone fracture, and then wait for the new tissue to grow and heal.

Simple single-walled carbon nanotubes are not sufficient, since the growth of hydroxyapatite crystals relies on the ability of the scaffold to attract calcium ions and initiate the crystallization process. So the researchers carefully designed nanotubes with several chemical groups attached. Some of these groups assist the growth and orientation of hydroxyapatite crystals, allowing the researchers a degree of control over their alignment, while other groups improve the biocompatibility of nanotubes by increasing their solubility in water.

"Researchers today are realizing that mechanical mimicry of any material alone cannot succeed in duplicating the intricacies of the human body," Haddon says. "Interactions of these artificial materials with the systems of the human body are very important factors in determining clinical use."

The research is still in the early stages, but Haddon says he is encouraged by the results. Before proceeding to clinical trials, Haddon plans to investigate the toxicology of these materials and to measure their mechanical strength and flexibility in relation to commercially available bone mimics.

http://www.eurekalert.org/pub_releases/ ... 070705.php

[SirNitram]

Fucking SWEET!

[wolveraptor]

Blinding small animals and making breakthroughs in medical technology? These guys have the best jobs evar.

[Drooling Iguana]

Too bad it can't cause their tails to grow back. Damn farmer's wife.

[Winston Blake]

This is the sort of nanotech i can see a great future for, not the molecular manufacturing nanobot stuff. Nanomaterials = good. Nanobots = teh suck.

[His Divine Shadow]

I can see a real use for this in say repairing the nerves in spinal columns.

[Crown]

I can see a real use for this in say repairing the nerves in spinal columns.

Exactly. Either due to trauma, or say a disease like MS.