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ewmayer 2010-06-25 15:27

Stem Cells For Corneal Damage a "Roaring Success"
[url=]Stem cells reverse blindness caused by chemical burns (AP)[/url]
[quote]Dozens of people who were blinded or otherwise suffered severe eye damage when they were splashed with caustic chemicals had their sight restored with transplants of their own stem cells — a stunning success for the burgeoning cell-therapy field, Italian researchers reported Wednesday.

The treatment worked completely in 82 of 107 eyes and partially in 14 others, with benefits lasting up to a decade so far. One man whose eyes were severely damaged more than 60 years ago now has near-normal vision.

"This is a roaring success," said ophthalmologist Dr. Ivan Schwab of the University of California, Davis, who had no role in the study — the longest and largest of its kind.

Stem cell transplants offer hope to the thousands of people worldwide every year who suffer chemical burns on their corneas from heavy-duty cleansers or other substances at work or at home.

The approach would not help people with damage to the optic nerve or macular degeneration, which involves the retina. Nor would it work in people who are completely blind in both eyes, because doctors need at least some healthy tissue that they can transplant.

In the study, published online by the New England Journal of Medicine, researchers took a small number of stem cells from a patient's healthy eye, multiplied them in the lab and placed them into the burned eye, where they were able to grow new corneal tissue to replace what had been damaged. Since the stem cells are from their own bodies, the patients do not need to take anti-rejection drugs.
Adult stem cells, which are found around the body, are different from embryonic stem cells, which come from human embryos and have stirred ethical concerns because removing the cells requires destroying the embryos.

Currently, people with eye burns can get an artificial cornea, a procedure that carries such complications as infection and glaucoma, or they can receive a transplant using stem cells from a cadaver, but that requires taking drugs to prevent rejection.

The Italian study involved 106 patients treated between 1998 and 2007. Most had extensive damage in one eye, and some had such limited vision that they could only sense light, count fingers or perceive hand motions. Many had been blind for years and had unsuccessful operations to restore their vision.

The cells were taken from the limbus, the rim around the cornea, the clear window that covers the colored part of the eye. In a normal eye, stem cells in the limbus are like factories, churning out new cells to replace dead corneal cells. When an injury kills off the stem cells, scar tissue forms over the cornea, clouding vision and causing blindness.

In the Italian study, the doctors removed scar tissue over the cornea and glued the laboratory-grown stem cells over the injured eye. In cases where both eyes were damaged by burns, cells were taken from an unaffected part of the limbus.

Researchers followed the patients for an average of three years and some as long as a decade. More than three-quarters regained sight after the transplant. An additional 13% were considered a partial success. Though their vision improved, they still had some cloudiness in the cornea.

Patients with superficial damage were able to see within one to two months. Those with more extensive injuries took several months longer.
One of the successful transplants in the Italian study involved a man who had severe damage in both eyes as a result of a chemical burn in 1948. Doctors grafted stem cells from a small section of his left eye to both eyes. His vision is now close to normal.

In 2008, there were 2,850 work-related chemical burns to the eyes in the United States, according to the Bureau of Labor Statistics.

Schwab of UC Davis said stem cell transplants would not help those blinded by burns in both eyes because doctors need stem cells to do the procedure.

"I don't want to give the false hope that this will answer their prayers," he said.

Dr. Sophie Deng, a cornea expert at the UCLA's Jules Stein Eye Institute, said the biggest advantage was that the Italian doctors were able to expand the number of stem cells in the lab. This technique is less invasive than taking a large tissue sample from the eye and lowers the chance of an eye injury.

"The key is whether you can find a good stem cell population and expand it," she said.[/quote]

cheesehead 2010-06-25 15:27

[quote=Spherical Cow;219869I]

Pretty scary-
[/quote]The comments, too.

Check #3 ("Ignorance like entropy goes only in one direction")

only_human 2010-06-29 05:56

[quote=ewmayer;219872][URL=""]Stem cells reverse blindness caused by chemical burns (AP)[/URL][/quote]
And here is a treatment that might repair dental cavities by the regeneration of teeth. [I]Tooth Regeneration Gel Could Replace Painful Fillings[/I] [URL][/URL]

apocalypse 2010-06-30 04:40

Donald Knuth promises [URL=""]"An Earthshaking Announcement"[/URL] tomorrow.

only_human 2010-06-30 12:10

[quote=apocalypse;220246]Donald Knuth promises [URL=""]"An Earthshaking Announcement"[/URL] tomorrow.[/quote]
Yeah, I noticed it mentioned on Slashdot. I looked around a bit trying to guess what's cooking but didn't catch a whiff. I consider it time well spent because I found this palindrome on Donald Knuth's website "All I saw Wasilla" and also because I found some interesting papers by a Kevin H. Knuth online. I especially liked [I]Deriving Laws from Ordering Relations [/I]

cheesehead 2010-06-30 20:17

[quote=only_human;220268]I consider it time well spent because I found this palindrome[/quote]Ahem ... that's [I]"Palin-[/I]drome", not merely palindrome.[quote=Donald Knuth]Message to Hannah Terret (née Terrett)

The Palin-drome I was trying to recall is: "All I saw: Wasilla."[/quote]

cheesehead 2010-07-08 16:10

"Goce satellite views Earth's gravity in high definition"


[quote][B]It is one of the most exquisite views we have ever had of the Earth.[/B]

This colourful new map traces the subtle but all pervasive influence the pull of gravity has across the globe.

Known as a geoid, it essentially defines where the level surface is on our planet; it tells us which way is "up" and which way is "down".

It is drawn from delicate measurements made by Europe's Goce satellite, which flies so low it comes perilously close to falling out of the sky.

. . .

One key beneficiary will be climate studies because the geoid can help researchers understand better how the great mass of ocean water is moving heat around the world.

. . .

Launched in 2009, the sleek satellite flies pole to pole at an altitude of just 254.9km - the lowest orbit of any research satellite in operation today.

The spacecraft carries three pairs of precision-built platinum blocks inside its gradiometer instrument that sense accelerations which are as small as 1 part in 10,000,000,000,000 of the gravity experienced on Earth.

This has allowed it to map the almost imperceptible differences in the pull exerted by the mass of the planet from one place to the next - from the great mountain ranges to the deepest ocean trenches.

. . .[/quote]

firejuggler 2010-07-08 17:26

[url=]baking is wonderfull! its like science for hungry people[/url]

only_human 2010-07-08 18:26

[quote=cheesehead;220336]Ahem ... that's [I]"Palin-[/I]drome", not merely palindrome.[/quote]I missed the significance of that but now am further rewarded because I've just learned that Palin-drome has a Palin specific entry in the Urban Dictionary: [URL][/URL][quote]Another Palin-drome from our favorite politician:

"As Putin rears his head and comes into the air space of the United States of America, where– where do they go? It's Alaska. It's just right over the border..."[/quote]

Batalov 2010-07-08 18:47

[URL=""]The size of the proton[/URL].
"...[This] result implies that either the Rydberg constant has to be shifted by −110[FONT=Arial Unicode MS] [/FONT]kHz/[I]c[/I] (4.9 standard deviations), or the calculations of the QED effects in atomic hydrogen or muonic hydrogen atoms are insufficient."

cheesehead 2010-07-08 19:32

[quote=only_human;220829]I missed the significance of that but now am further rewarded because I've just learned that Palin-drome has a Palin specific entry in the Urban Dictionary: [URL][/URL][/quote]Did you catch the name of the person to whom his message was addressed?

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