SCIENTISTS are claiming an amazing breakthrough - regrowing a man's severed finger with the aid of an experimental powder.
Four weeks after Lee Spievack sliced more than 1cm off the top of one of his fingers, he said it had grown back to its original length.
Four months later it looked like any other finger, complete with "great feeling", a fingernail and fingerprint.
The secret to the astonishing regrowth is said to be the powder described by Mr Spievack, a Cincinnati model shop salesman, as "pixie dust".
More properly known as extra-cellular matrix, it is bursting with collagen, the protein that gives skin its strength and elasticity, and is made from dried pig's bladder. It was developed to regenerate damaged ligaments in horses.
"The second time I put it on I could already see growth," said Mr Spievack, 69. "Each day it was up further.
"Finally it closed up and was a finger. It took about four weeks before it was sealed."
Mr Spievack damaged his finger in the propeller of a model plane three years ago. He turned down a skin graft in favour of the "pixie dust" recommended by his brother, a former surgeon and the founder of the firm that makes the powder.
While it is not entirely clear how the powder works, its developers believe it kick-starts the body's natural healing process by sending out signals that mobilise the body's own cells into repairing the damaged tissue.
Dr Stephen Badylak, of the McGowan Institute for Regenerative Medicine at the University of Pittsburgh, told the BBC: "There are all sorts of signals in the body. We have got signals that are good for forming scar tissue and others that are good for regenerating tissues.
"One way to think about these matrices is that we've taken out many of the stimuli for scar tissue formation and left those signals which were always there for constructive remodelling."
In other words, the powder directs tissues to grow afresh rather than form scars.
He believes the powder also forms a microscopic scaffolding for the body's own cells to build round.
http://www.news.com.au/story/0,23599,23630035-13762,00.html