Newsgroup: it.cultura.religioni
Titolo: xchè accanirsi con gli embrioni??

quando e' sempre piu' evidente che le ricerche prospettano vie nuove!
http://wired.com/news/medtech/0,1286,67155,00.htmlhttp://wired.com/news/medtech/0,1286,67155,00.html
 
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le tipiche evidenze dei cattolici 


io con :
 
http://wired.com/news/medtech/0,1286,67155,00.html
leggo questo:
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Lop off a newt's leg or tail, and it will grow a new one.
The creature's cells can regenerate thanks to built-in time machines that
revert cells to early versions of themselves in a process called
dedifferentiation.
Researchers who study this mechanism hope one day to learn how to induce the
same "cell time travel" in humans. If the cells go back far enough, they
become stem cells, which researchers believe hold promise for treating many
diseases. Stem cells, which are often taken from embryos, are unformed and
have the ability to become many different types of cells. If researchers
succeed in inducing this cell time travel, they will also eliminate the
ethical issues surrounding embryonic stem-cell research, because no embryos
would be destroyed to obtain the cells.
  LNX & MS Managed Servers. 24x7 Support. 0% Downtime! The research is in its
infancy, but a 2001 discovery jump-started the field of study. Mark Keating,
Christopher McGann and Shannon Odelberg applied a protein extract derived
from newts to mouse muscle cells. To their surprise, the protein extract
transformed those muscle cells into stem cells in just 48 hours, which means
the mouse cells would have the ability to regenerate.
No one expected the experiment to work. Previously, scientists believed that
once mammalian cells became muscle, bone or any other type of cells, that
was their fate for life -- and if those cells were injured, they didn't
regenerate, but grew scar tissue.
But Keating's experiment introduced the possibility that, under the right
circumstances, humans -- who are 99 percent genetically similar to mice --
might one day be able to regenerate their own cells. Those regenerated cells
could be used to treat disease.
"For those of us who want to understand what happens in dedifferentiation,
our ultimate goal is to be able to form a pool of stem-cell-like cells that
would be able to repopulate the organ or tissue you're trying to repair,"
said Catherine Tsilfidis, a scientist at the Ottawa Health Research
Institute who has reproduced Keating's findings, which she describes as
"beautiful."
In newts and some other animals with the ability to regenerate, cells at the
site of an injury can revert to their embryonic stem-cell stage and can
become another type of cell in that creature's body. In other words, a skin
cell can dedifferentiate into a stem cell, then regenerate into a muscle
cell or another completely different type of cell.
Tsilfidis and her colleagues are now trying to pinpoint which genes are
responsible for kick-starting newt dedifferentiation. They published
findings in the March 23 issue of Developmental Dynamics identifying 59 DNA
fragments that seem to play a role in newt forelimb regeneration, and
Tsilfidis believes many of those gene fragments have counterparts in humans.
"Whether (those genes) can actually induce dedifferentiation is yet to be
determined," Tsilfidis said. While the genes were active during maximum
dedifferentiation activity, she said, so much is going on in cells after a
newt's forelimb is cut off that it's difficult to pick out specific
dedifferentiation genes.
While some cells are dedifferentiating, others have already begun
regenerating and differentiating, or becoming specialized cells. They're
performing activities like healing wounds or growing blood vessels, so it's
difficult to pin certain genes to specific activities.
Researchers are trying to learn similar lessons from other creatures that
have the ability to regenerate, including starfish, zebrafish, earthworms
and lobsters.
Adult human bodies do contain some stem cells, but they are rare.
"Maybe only one in a million cells in a particular region might have that
regenerative capacity you're interested in," said Robert Naviaux, who
studies cancer and stem-cell differentiation, and is co-director of the
Mitochondrial and Metabolic Disease Center at the University of California
at San Diego. "Stem cells are more concentrated in certain locations like
human umbilical cords, blood and bone marrow, and certain areas of the brain
around the ventricles."
People who believe it's unethical to destroy any embryos, even those
abandoned and destined for destruction at in vitro fertilization clinics,
have touted adult stem cells as an ethical choice. The field has seen some
success, but many researchers believe adult stem cells have less
"plasticity," or ability to become different types of cells.
Others have promoted various schemes for getting around the embryo
conundrum, but none has received a unanimous stamp of approval from
scientists and religious groups or others who oppose the destruction of
embryos.
But at least one religious leader believes the ability to use
dedifferentiation to create human stem cells would eliminate the
controversy.
"I believe that dedifferentiation -- the direct conversion of a somatic cell
into an embryonic stem cell -- is the holy grail for those seeking morally
acceptable alternatives to the destructive embryo research now required to
obtain (embryonic stem) cells," said Father Nicanor Austriaco, a molecular
biologist and Catholic priest in Washington, D.C. "You would also be able to
get immunocompatible (embryonic stem) cells from every patient by simply
dedifferentiating his or her cells. This would be an amazing discovery."
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traduco solo qs. ultimo:
io credo che la 'dedifferenziazione' - la conversione diretta di cellule del
proprio corpo in _staminali_ - e' il 'santo graal' per chi cerca accettabili
alternative, da un pdv morale, alla distruzione di embrioni ...
ma siccome chi lo dice e' un cattolico, ovviamente e' da CESTINARE!
of course, come ha proprio scritto tu.
pietro
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