This is what is absolutely needed before we go any farther with testing stem cells for stroke. Any research that doesn't use this is worthless. It is why I don't trust any reporting on Gordie Howe.
http://www.biosciencetechnology.com/news/2015/05/stem-cells-transplanted-followed-brain?et_cid=4547246&et_rid=648870051&location=top
Investigators at the Stanford University School of Medicine have devised
a way to monitor neural stem cells after they’ve been transplanted into
the brain.
The scientists were able to determine not only whether the stem cells
transplanted into living animals survived but whether they matured into
nerve cells, integrated into targeted brain circuits and, most
important, were firing on cue and igniting activity in downstream nerve
circuits.
The new monitoring technique could in principle be used to determine the
success of other kinds of stem cell transplantations. It promises in
the near term to improve researchers’ ability to optimize stem cell
therapies in animal experiments and, in the intermediate term, to speed
progress in human trials of stem cell replacement therapy, a promising
but problem-plagued medical intervention.
Many disorders of the central nervous system, such as Parkinson’s
disease, are characterized by defective nerve cells in specific brain
regions. This makes disorders such as Parkinson’s excellent candidates
for stem cell therapies, in which the defective nerve cells are
replaced. But the experiments in which such procedures have been
attempted have met with mixed results, and those conducting the
experiments are hard put to explain them. There’s been no good way to
evaluate what the transplanted stems cells are doing. So optimizing the
regimens becomes a matter of guesswork and luck.
“That’s the key missing step in stem cell therapy design: Once you’ve
transplanted the cells, you can’t tell exactly what they’re doing
afterwards,” said Jin Hyung Lee, Ph.D., assistant professor of
neurology, of neurosurgery and of bioengineering. In the case of
brain-oriented therapies, you have to look for behavioral changes, she
said. “And even when you see them, you still don’t know whether the
newly transplanted cells integrated into the right brain circuits and
are now functioning correctly there.”
Now there’s a way to tell.
Transplanted stem cells did what they were supposed to
Lee is the senior author of a paper, appearing online April 30 in NeuroImage,
detailing a series of experiments in which she and her colleagues
combined functional magnetic resonance imaging, or fMRI, with a
relatively new but increasingly widespread technology known as
optogenetics, which employs laser light to stimulate specific cells that
have been rendered sensitive to particular frequencies of light. The
combination let the scientists selectively stimulate only nerve cells
derived from newly transplanted neural stem cells, while simultaneously
assessing resulting nerve-cell activity at the site of the transplant
and elsewhere in the brain.
The study showed that the
transplanted neural stem cells had indeed matured into nerve cells that
not only integrated into the brain’s circuitry at the transplantation
site but could be induced to fire electrical signals on command, and
that this signaling triggered activity in other areas of the brain. Lead
authorship of the study is shared by former graduate student Blake
Byers, Ph.D., now a general partner with Google Ventures; postdoctoral
scholar Hyun Joo Lee, Ph.D.; and Ph.D. students Jia Liu and Andrew
Weitz.
The researchers first created induced pluripotent stem cells, or iPS
cells, from the skin cells of a patient with Parkinson’s disease. Like
embryonic stem cells, iPS cells have the capacity to differentiate into
every cell type in the human body. Next, they inserted a gene coding for
a photosensitive protein into these iPS cells. The protein situates
itself on the cell’s surface and, in response to blue laser light,
induces electrical activity in the cell.
Then, in a dish, the researchers differentiated the genetically altered
iPS cells into neural stem cells. Unlike iPS cells, which can
differentiate into every cell type in the body, neural stem cells can
mature only into nerve cells or a few other cell types that populate the
brain.
The scientists transplanted these genetically altered human cells into
the brains of rats that were normal except for the fact that their
immune systems were compromised, reducing the chances of an immune
attack on the foreign cells.
The particular region of the brain into which the cells were injected is
called the striatum. In humans, deterioration of particular nerve cells
in this area is a hallmark of Parkinson’s disease, a progressive
neurodegenerative disorder profoundly affecting movement and,
frequently, mental function. Along with the new cells, the investigators
implanted into each rat’s brain a small cannula containing the end of a
thin optical fiber whose far end could be connected to a laser light
source.
From about three months to almost a full year after the procedure, Lee
and her associates conducted experiments in which, using fMRI, they
observed the rats’ brains before, during and after stimulating the
implanted cells with pulses of blue laser light or, as a control, yellow
laser light. Blue-light stimulation triggered activity not only within
the striatum but at several other areas in the brain. Yellow light had
no effect — proof that electrical activity in these cells had been
triggered by stimulating the genetically inserted protein, not merely by
shining light on them.
Recording electrical activity
To explore activity in those areas, the researchers turned to a
different observation method: electrophysiology. While fMRI has the
advantage of imaging large portions of the brain simultaneously, it
actually measures not electrical activity but blood flow in the small
vessels permeating the entire brain. Active nerve cells require more
nutrients, and increased blood flow in a specific location in the brain
is considered an excellent proxy of electrical activity at that
location.
But, having now identified specific brain areas where fMRI scans
indicated increased nerve-cell activity, Lee and her associates
proceeded to directly record electrical activity in these areas by
inserting electrodes there and watching what happened when they pulsed
blue light into the striatum, where the neural stem cells had been
transplanted. They saw, first, that the transplanted nerve cells had
clearly integrated into striatal circuitry and were firing there when
stimulated with blue light; and, second, that this triggered electrical
follow-on activity in remote regions of the brain.
Anatomical inspections of the rats’ brains confirmed that the new cells
had integrated into the striatum and, in many cases, had grown long
projections to the remote areas where follow-on activity had been
observed.
“I’m hopeful that this monitoring approach could work for all kinds of
stem cell-based therapies,” Lee said. “If we can watch the new cells’
behaviors for weeks and months after we’ve transplanted them, we can
learn — much more quickly and in a guided way rather than a
trial-and-error fashion — what kind of cells to put in, exactly where to
put them, and how.”
The study was funded by the National Institutes of Health, the Okawa
Foundation, a National Science Foundation Early Faculty Development
Program award, an Alfred P. Sloan Research Fellowship and the California
Institute for Regenerative Medicine.
Use the labels in the right column to find what you want. Or you can go thru them one by one, there are only 28,987 posts. Searching is done in the search box in upper left corner. I blog on anything to do with stroke.DO NOT DO ANYTHING SUGGESTED HERE AS I AM NOT MEDICALLY TRAINED, YOUR DOCTOR IS, LISTEN TO THEM. BUT I BET THEY DON'T KNOW HOW TO GET YOU 100% RECOVERED. I DON'T EITHER, BUT HAVE PLENTY OF QUESTIONS FOR YOUR DOCTOR TO ANSWER.
Changing stroke rehab and research worldwide now.Time is Brain! trillions and trillions of neurons that DIE each day because there are NO effective hyperacute therapies besides tPA(only 12% effective). I have 523 posts on hyperacute therapy, enough for researchers to spend decades proving them out. These are my personal ideas and blog on stroke rehabilitation and stroke research. Do not attempt any of these without checking with your medical provider. Unless you join me in agitating, when you need these therapies they won't be there.
What this blog is for:
My blog is not to help survivors recover, it is to have the 10 million yearly stroke survivors light fires underneath their doctors, stroke hospitals and stroke researchers to get stroke solved. 100% recovery. The stroke medical world is completely failing at that goal, they don't even have it as a goal. Shortly after getting out of the hospital and getting NO information on the process or protocols of stroke rehabilitation and recovery I started searching on the internet and found that no other survivor received useful information. This is an attempt to cover all stroke rehabilitation information that should be readily available to survivors so they can talk with informed knowledge to their medical staff. It lays out what needs to be done to get stroke survivors closer to 100% recovery. It's quite disgusting that this information is not available from every stroke association and doctors group.
Sunday, May 3, 2015
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