On 6 May, 04:09, BooBool...@[EMAIL PROTECTED]
wrote:
> On May 1, 8:07=A0am, Dragonblaze <dragonbl...@[EMAIL PROTECTED]
> wrote:
>
>
>
>
>
> > NEW YORK =97 =A0Researchers are trying to find ways to regrow fingers
=
=97
> > and someday, even limbs =97 with tricks that sound like magic spells
> > from a Harry Potter novel.
>
> > There's the guy who sliced off a fingertip but grew it back, after he
> > treated the wound with an extract of pig bladder. There are also the
> > scientists who grow extra arms on salamanders, and the laboratory mice
> > with the eerie ability to heal themselves.
>
> > This summer, scientists are planning to see whether the powdered pig
> > extract can help injured soldiers regrow parts of their fingers. A
> > large federally funded project is trying to unlock the secrets of how
> > some animals regrow body parts so well, with hopes of applying the the
> > lessons to humans.
>
> > =95 Click here to visit FOXNews.com's Human Body Center.
>
> > The implications for regrowing fingers go beyond the cosmetic. People
> > who are missing all or most of their fingers, as from an explosion or
> > a fire, often can't pick things up, brush their teeth or button a
> > button.
>
> > If they could grow even a small stub, it could make a huge difference
> > in their lives.
>
> > The lessons learned from studying regrowth of fingers and limbs could
> > aid the larger field of regenerative medicine, perhaps someday helping
> > people replace damaged parts of their hearts and spinal cords, and
> > heal wounds and burns with new skin instead of scar.
>
> > But that's in the future. For now, consider the situation of Lee
> > Spievack, a hobby-store salesman in Cincinnati, as he regarded his
> > severed right middle finger one evening in August 2005.
>
> > He had been helping a customer with an engine on a model airplane
> > behind the shop. He knew the motor was risky because it required
> > somebody to turn the prop backwards to make it run the right way.
>
> > "I pointed to it," Spievack recalled the other day, "and said, 'You
> > need to get rid of this engine, it's too dangerous.' And I put my
> > finger through the prop."
>
> > He'd misjudged the distance to the spinning plastic prop. It sliced
> > off his fingertip, leaving just a bit of the nail bed. The missing
> > piece, three-eighths of an inch long, was never found.
>
> > An emergency room doctor wrapped up the rest of his finger and sent
> > him to a hand surgeon, who recommended a skin graft to cover what was
> > left of his finger. What was gone, it appeared, was gone forever.
>
> > If Spievack, now 68, had been a toddler, things might have been
> > different. Up to about age 2, people can consistently regrow
> > fingertips, says Dr. Stephen Badylak, a regeneration expert at the
> > University of Pittsburgh. But that's rare in adults, he said.
>
> > Spievack, however, did have a major advantage =97 a brother, Alan, a
> > former Harvard surgeon who'd founded a company called ACell Inc., that
> > makes an extract of pig bladder for promoting healing and tissue
> > regeneration.
>
> > It helps horses regrow ligaments, for example, and the federal
> > government has given clearance to market it for use in people. Similar
> > formulations have been used in many people to do things like treat
> > ulcers and other wounds and help make cartilage.
>
> > The summer before Lee Spievack's accident, Dr. Alan Spievack had used
> > it on a neighbor who'd cut his fingertip off on a tablesaw. The man's
> > fingertip grew back over four to six weeks, Alan Spievack said.
>
> > Lee Spievack took his brother's advice to forget about a skin graft
> > and try the pig powder.
>
> > Soon a ****pment of the stuff arrived and Lee Spievack started applying
> > it every two days.
>
> > Within four weeks his finger had regained its original length, he
> > says, and in four months "it looked like my normal finger."
>
> > Spievack said it's a little hard, as if calloused, and there's a
> > slight scar on the end. The nail continues to grow at twice the speed
> > of his other nails.
>
> > "All my fingers in this cold weather have cracked except that one," he
> > said.
>
> > All in all, he said, "I'm quite impressed."
>
> > None of this proves the powder was responsible. But those outcomes
> > have helped inspire an effort to try the powder this summer at Fort
> > Sam Houston in San Antonio, on soldiers who have far more disabling
> > finger loss because of burns.
>
> > Fingers are particularly vulnerable to burns because they are small
> > and their skin is thin, says David Baer, a wound specialist at the
> > base who's working on the federally funded project.
>
> > The five to 10 patients in the project will be chosen because they
> > have major losses in all their fingers and thumbs, preventing them
> > from performing the pinching motion they need to hold a toothbrush,
> > for example.
>
> > The soldiers will have the end of a finger stub re-opened surgically,
> > with the powder applied three times a week.
>
> > Nobody is talking about regrowing an entire finger. The hope is to
> > grow enough of a finger, maybe even less than an inch, to do pinching.
>
> > It is just a hope.
>
> > "This is a real shot in the dark," says Badylak, who's participating
> > in the project. "There's literally nothing else these individuals have
> > to try. They have nothing to lose."
>
> > But from a scientific standpoint, he said, "this isn't ready for prime
> > time."
>
> > For one thing, it's not completely clear what happened inside Lee
> > Spievack's finger.
>
> > The broad outline is pretty straightforward. The powder is mostly
> > collagen and a variety of substances, without any pig cells, said
> > Badylak, who's a scientific adviser to ACell. It forms microscopic
> > scaffolding for incoming human cells to occupy, and it emits chemical
> > signals to encourage those cells to regenerate tissue, he said.
>
> > Those signals don't specifically say "make a finger," but cells pick
> > up that message from their surroundings, he said.
>
> > "We're not smart enough to figure out how to regrow a finger," Badylak
> > said. "Maybe what we can do is bring all the pieces of the puzzle to
> > the right place and then let Mother Nature take its course."
>
> > But "we are very uninformed about how all of this works," Badylak
> > said. "There's a lot more that we don't know than we do know."
>
> > Some animals, of course, can regenerate tissue without help from any
> > powder. Badylak and other scientists are involved in a separate,
> > Pentagon-funded project to uncover and harness their secrets. This
> > work might someday lead to regenerating entire limbs.
>
> > One animal they're studying is the salamander, a star of the
> > regeneration field. Chop off a salamander's arm, and it will grow back
> > in a matter of weeks.
>
> > Why? The short answer is that rather than making a scar to heal
> > quickly, as people do, the salamander forms a mound of cells called a
> > blastema.
>
> > This is a regeneration factory: If you cut off a salamander hand and
> > transplant the resulting blastema to the creature's back, it will grow
> > out a hand there.
>
> > David Gardiner at the University of California, Irvine, is studying
> > the secrets of the salamander by growing extra arms on the creatures.
> > That allows for more controlled conditions than amputating arms and
> > trying to follow what happens, he said.
>
> > So how do you make a salamander grow an extra arm? Make a shallow
> > wound on the upper arm. Re-route a nerve to the site so it will pump
> > out critical chemical signals that promote the creation of blastema
> > cells. Then insert a tiny piece of skin from the other side of the
> > limb you just wounded, to help provide a blueprint for what needs to
> > be done.
>
> > The recipe sounds like "you put it in a cauldron under a full moon,"
> > Gardiner observed.
>
> > The creatures are so lethargic it's hard to tell if they can use their
> > extra arms, he noted. But the research shows that beyond establi****ng
> > a blueprint for a new arm, this mix of cells sends out a chemical
> > S.O.S. to attract other kinds of cells from the salamander's body to
> > help construct a new appendage.
>
> > Just how many chemical signals are involved, and what they are, remain
> > to be discovered.
>
> > Then there's the specially bred mouse strain that befuddled Ellen
> > Heber-Katz a decade ago, and has since become a focus of her research.
>
> > Heber-Katz, of the Wistar Institute in Philadelphia, was using the
> > mouse strain known as MRL in a study of autoimmune diseases. Her team
> > punched tiny holes in the animals' ears as markers. About three weeks
> > later, Heber-Katz noticed a troubling thing.
>
> > "There were no ear holes," she recalled the other day. "We ear-punched
> > again, and they closed up and disappeared.... We were just so
> > shocked."
>
> > Like salamanders, the mice were growing blastemas instead of scars.
> > They also heal damage to their hearts.
>
> > But for regrowing digits, even this mouse falls short. If a toe is cut
> > off at some point other than the tip, the remnant produces a cell mass
> > that looks like a small blastema, but it doesn't grow the missing part
> > back. (An ordinary mouse just develops a scar.)
>
> > At least, the MRL mouse "looks like it's trying," Heber-Katz said.
>
> > In studying the mice and salamanders, scientists will pursue several
> > questions. What genes rev up to produce regrowth? What biochemical
> > signals are involved? What is the role of specific cells? Can this
> > knowledge be used to regrow a digit on a mouse?
>
> > Scientists say it's not clear when this research might help people.
>
> > As for Spievack, the model-airplane enthusiast, he's had enough
> > personal experience in this area.
>
> > "I don't plan on cutting anything more off to find out if I can grow
> > that back," he said.
>
> >http://www.foxnews.com/story/0,2933,252704,00.html
>
> > Dragonblaze
>
> > - Faith cannot move mountains, but look what it can do to
> > skyscrapers!. -
>
> Even if any of this is factual, it is wrong, a priori.- Hide quoted text
-=
Okay, I'll bite. Why would it be wrong?
Dragonblaze
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