~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The Raelian Movement
for those who are not afraid of the future : http://www.rael.org
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
McMaster researchers say not all stem cells the same
http://www.physorg.com/news/2010-10-mcmaster-stem-cells.html
October 19, 2010 By Laura Thompson
Until now it's been thought that human stem cell lines are all
identical and possess the same ability to differentiate, or change
into more specific cell types. But new research from McMaster
University has shown there are subsets of stem cells that respond
differently depending on what stem cell properties are measured and
what test is used.
"We discovered pluripotent stem cells [cells capable of giving rise to
several different cell types] in humans are not made equally and
they're certainly not measured equally," said Mick Bhatia, scientific
director of the McMaster Stem Cell and Cancer Research Institute and a
lead author of the study. "This study affirms that we should no longer
make the assumption that every stem cell is the same or has the same
potential."
The research, funded by the Canadian Institutes of Health Research,
was published online Oct. 17 in the prestigious journal Nature
Methods.
Stem cells give rise to at least 226 different cell types in the human
body, but scientists don't use the same litmus test to measure each
kind. Instead, they follow a specific set of instructions - or recipe
- to produce a blood cell or a neural cell, for example. They also
examine how stem cells become specialized by measuring them either in
a culture dish or in a mouse. That may change.
Bhatia and his team discovered at least four subsets of stem cells
that vary in their capacity to differentiate or make copies of
themselves, a stem cell property called self-renewal. The researchers
found that some stem cells differentiate only in a culture dish, while
others differentiate only in mice. They found a third subset that
didn't respond at all, and a fourth subset - a small fraction of the
cells - that differentiated in both environments.
"People have always understood that there are probably differences in
cells in the dish, but they couldn't measure the differences and they
didn't know the contribution of stem cells to one measure versus
another, or the impact of those differences," said Bhatia, a professor
in the Department of Biochemistry and Biomedical Sciences.
The massive research study was conducted over four and a half years by
investigators in the McMaster Stem Cell and Cancer Research Institute.
The study involved "permanent" tagging of hundreds of stem cells by
inserting a piece of DNA into them. The researchers then measured the
differentiation capacity of each stem cell by using cell-based tests,
known as functional assays, and following the tag.
Bhatia said the research could signal a new approach to the way stem
cells are measured. It could also lead to a different interpretation
of previous data or a refined approach to cell-replacement therapy.
"This study has implications on stem-cell-based regenerative medicine.
We actually didn't know which stem cells were responding to our
recipes until we did this experiment," he said. "As we move forward,
the methods in which we evaluate stem cells are critical. If the
methods are wrong, or misinterpreted, it changes everything."
Provided by McMaster University
"Ethics" is simply a last-gasp attempt by deist conservatives and
orthodox dogmatics to keep humanity in ignorance and obscurantism,
through the well tried fermentation of fear, the fear of science and
new technologies.
There is nothing glorious about what our ancestors call history,
it is simply a succession of mistakes, intolerances and violations.
On the contrary, let us embrace Science and the new technologies
unfettered, for it is these which will liberate mankind from the
myth of god, and free us from our age old fears, from disease,
death and the sweat of labour.
Rael
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-----------------------------------------------------------------
Tell your friends who love scientific news that they can
subscribe to this list !!
They can do it by sending a blank email to:
rael-science-select-subscribe@yahoogroups.com
It's free !
-----------------------------------------------------------------
To unsubscribe, send an email to:
rael-science-select-unsubscribe@yahoogroups.com
-----------------------------------------------------------------
To change your e-mail address, unsubscribe from the old address and subscribe from the new address (see above).
-----------------------------------------------------------------
0 comments:
Post a Comment