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Scientists Coax Nerve Fibers To Regrow
Malthooslie writes to tell us ScienceDaily is reporting that scientists have managed to regrow nerve fibers after a spinal injury. Using an enzyme called sialidase, isolated from bacteria, researchers were able to stimulate nerve fiber growth in rats. From the article: "While surgeons can sometimes reattach the yanked nerves to the spinal cord, this treatment is not as effective as physicians or patients would like. This is in part because nerves in the brain and spinal cord, unlike those in the rest of the body, fail to grow new nerve fibers. Nerves in the brain and spinal cord are surrounded by signals from other cells in the injured area that stop them from growing."
1 To persuade or try to persuade by pleading or flattery; cajole. 2 To obtain by persistent persuasion: coaxed the secret out of the child. 3 Obsolete. To caress; fondle. 4 To move to or adjust toward a desired end: "A far more promising approach to treating advanced melanoma is to coax the immune system to recognize melanoma cells as deadly" (Natalie Angier). See #4. Also please learn all the meanings of a word before trying to make fun of someone for improper usage
Does a line appended to your comment give your post meaning in and of itself, or only in relation to those without?
Unlikely. Multiple sclerosis is an autoimmune disorder, and even if new nerves could be generated, they would be just as susceptible to attack by the host immune system.
Let's try not to let fact interfere with our speculation here, OK?
Not the same. That was stem cells to grow new nerve cells, this is an enzyme to cause nerve cells to grow new connections.
;)
Keep your paralyzed rats straight here
Nerves don't transmit electricity per say, the transmission happens through a progression of chemicals being dumped from an axon and a in flux of ions from outside coming in which cause a similar reaction down the line at another membrane gate on the axon. Its an elctrochemical reaction that carries the signal in a axon.
(My biology is a little rusty, so maybe someone can better explain it.)
As vix86 points out, it's not the electrical signals that matter. The human nervous system is not based on electricity, but on ions; the application of electricity to the skin will cause those ions to move, since they're charged particles, but the nervous system itself is purely chemical. For one thing, it doesn't have any closed circuits - the nerve system is entirely radiative, pointing outwards but with no equivalents of wires that come back. What matters here is the synapses. When these are ripped out of place by medical trauma, it's damn hard to fit them back together again - in the rest of the body, it works, but in the spinal cord there's other cells present that effectively inhibit this healing.
Browsing with +2 to insightful posts and a higher threshold makes the average post seen seem a lot more ingenious
Actually, it's electro-chemical. Signal transmission along the axon works by having a depolarized zone travelling down the axon. The depolarization happens electrically, this is why having a myelin sheath around the axon will speed up signal transmission (the depolarization can "skip" the parts of the axon covered by the myelin sheath).
Signal transmission between two nerve cells is a chemical process that happens in the synaptic cleft, involving neurotransmitters and enzymes to break them down.
What matters here is the synapses. When these are ripped out of place by medical trauma, it's damn hard to fit them back together again - in the rest of the body, it works, but in the spinal cord there's other cells present that effectively inhibit this healing.
Actually, no, the synapses are not the biggest problem. They're simply a connection between two cells that can be reformed fairly easily (nerve cells have a natural tendency to try to establish meaningful connections with other nerve cells). The big problem is having nerve fibers that are cut - the usual healing process of the body consists of disposing of damaged cells and replacing them with newly formed cells. This obviously doesn't work with neurons as they usually cannot be re-grown. Therefore, if a neuron is damaged, it has to be _repaired_, not _replaced_, and this is the hard part.
cells is outdated. I am not an expert, but more and more I hear of different results, e.g. here: http://www.abc.net.au/science/news/stories/s59648. htm
Great idea in theory, but very hard to put into practice. First of all, there are a lot of immunological compatability issues when transferring blood or serum from one organism to another. The human (and mouse) body has an amazing system to recognize foreign material and destroy it, and the bood wouldn't last very long. The second issue is cost. It would be very hard to get a large enough quantity of infant blood to "bathe" an injured area (short of pushing the limits of ethics, which our country seems unwilling to do as of late). "Why not use synthetic materials?" Basically the same two reasons. Synthetic proteins are "copies" of what is naturally produced. However, there are a lot of modifications and interactions that occur in the body that synthetic materials don't undergo, and therefore don't work as well as the natural anologue. Also, making synthetic serum would be very expensive, since there are a lot of elements interacting, and we have no idea what's actually making the difference. That having been said, studying these interactions and coming up with strategies (like introducing specialized bacteria, certain blocker molecules, or even *gasp* stem cells to the mix) is a very promising field, and is being worked on in labs all over the world.