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pharmalive.com
hype&hope.com
http://www.BioMedSearch.com
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-
 Stem cells
"have the remarkable
potential to develop into many different cell types in the
body during early life and growth.
In addition, in many
tissues they serve as a sort of
internal repair system,
dividing essentially without limit to replenish other cells
as long as the person or animal is still alive. When a stem
cell divides, each new cell
has the potential either to
remain a stem cell or become another type of cell with a
more specialized function, such as a muscle cell, a red
blood cell, or a brain cell.
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- Stem
cells are distinguished from other cell types by two
important characteristics. First, they are unspecialized
cells capable of renewing themselves through cell division,
sometimes after long periods of inactivity. Second, under
certain physiologic or experimental conditions, they can be
induced to become tissue- or organ-specific cells with
special functions. In some organs, such as the gut and bone
marrow, stem cells regularly divide to repair and replace
worn out or damaged tissues. In other organs, however, such
as the pancreas and the heart, stem cells only divide under
special
conditions."
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What is Stem
Cell Research?
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Stem cell research is an emerging technology that examines the therapeutic use of
undifferentiated cells in treating different disorders,
injuries, and diseases.
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Undifferentiated cells
are cells that have not assumed a specific cell type
yet.
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Are
All Stem Cells the Same?
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No. There are many types of
stem cells, but they can be classified into two basic
groups:
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1.
Adult stem cells
repair and
maintain healthiness of the tissue or organ in which they
are found.
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2.
Embryonic stem cells
are found on the
inner cell mass of a human blastocyst.
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Embryonic Stem Cells
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Embryonic stem cells are taken from an early embryo.
"Most embryonic stem cells are derived from embryos
that develop from eggs that have been fertilized
in vitro—in an
in vitro fertilization
clinic—and then donated for research purposes with
informed consent of the donors. They are not derived
from eggs fertilized in a woman's body."
"Stem Cell Basics:
What are Embryonic Stem Cells?" Stem Cell Information. National
Institutes of Health, U.S. Department of Health and Human
Services, 2009. 5 February 2011. <http://stemcells.nih.gov/info/basics/basics3.asp>.
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Pros and Cons of Embryonic and Adult Stem Cells |
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Advantages |
Disadvantages |
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Embryonic Stem Cells |
1. Flexible—appear to have the potential to make any
cell. 2.
Immortal—one ES cell line can potentially provide an endless
supply of cells with defined
characteristics.
3. Availability—embryos from in vitro fertilization clinics. |
1. Difficult to differentiate uniformly and homogeneously
into a target tissue.
2. Immunogenic—ES cells from a random embryo donor are
likely to be rejected after transplantation.
3. Tumorigenic—Capable of forming tumors or promoting tumor
formation.
4. Destruction of developing human life.
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Adult Stem Cells |
1. Special adult-type stem cells from bone marrow and from
umbilical cord have been isolated recently which appear to
be as flexible as the embryonic type.
2. Already somewhat specialized—inducement may be simpler.
3. Recipients will not experience rejection.
4. Relative ease of procurement- some adult stem cells are
easy to harvest (skin, muscle, marrow, fat), while others
may be more difficult to obtain (brain stem cells).
5. Non-tumorigenic.
6. No harm done to the donor.
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1. Limited quantity—can sometimes be difficult to obtain in
large numbers.
2. Finite—may not live as long as ES cells in culture.
3. Less flexible (with the exception of #1 above)—may be
more difficult to reprogram to form other tissue types.
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Potential
Treatments
http://www.stemcellresearch.org/facts/asc-refs.pdf ~
http://www.stemcellresearch.org/facts/treatments.htm
Stem Cell Articles and Information:
• Spinal Cord Injury
• Cancer:
Research injecting neural (adult) stem cells into the
brains
of
dogs can be very successful in treating
cancerous
tumors.
Researchers at the Harvard Medical School injected adult stem cells
genetically engineered
to convert
a separately injected non-toxic substance into a cancer-killing
agent. Within days the adult stem cells had migrated into the
cancerous area and the injected substance was able to reduce tumor
mass by 80 percent.
• Alzheimer's:
Clinical Trials in the
U.S.,
X-Cell Center in Germany
offering treatment,
Facts & Information
Including Stem Cell Treatment;
“Adult
stem cell therapy offers a safe and effective treatment for a
disease which was previously considered to be irreversible. Not only
for Alzheimer’s disease but also for other neurological disorders,
adult stem cell therapy provides a healthy and efficacious
alternative to drug-related therapies.”
• MS:
BBC Article,
Video of Patient seeing remarkable results
from stem cells,
Another video,
http://www.regenecell.com/article-multiple-sclerosis-status.htm
• Muscle damage after heart attacks:
Adult stem cells are also
apparently able to repair
muscle
damaged after
heart
attacks.
Researchers at Columbia-Presbyterian found that injecting
bone-marrow stem cells, a form of adult stem
cells, into mice which had had heart attacks induced resulted in an
improvement of 33 percent in the functioning of the heart. The
damaged tissue had regrown by 68%.
• Heart Damage:
VesCell™ Adult Stem Cell
Therapy for Heart Disease,
TX Heart Institute
treating heart conditions;
By using a catheter and transplanting
ASM (autologous skeletal myoblasts) into scarred tissue, living
muscle can be regenerated with limited risk to the patient.
• Low blood supply:
By creating
an environment that mimics the conditions of bone marrow and adding
Erythropoietin,
the stem cells are coaxed to complete terminal differentiation into
red blood cells which is a method to produce large numbers of red
blood cells.
• Missing Teeth:
In 2004,
scientists at King's College discovered a way to cultivate a
complete tooth in mice and were able to grow them stand-alone in the
laboratory. Researchers are confident that this technology can be
used to grow live teeth in human patients. In theory, stem cells
taken from the patient could be coaxed in the lab into turning into
a tooth bud which, when implanted in the gums, will give rise to a
new tooth, which would be expected to take two months to grow.
• Blindness:
Stem Cells
Cure Blindness, Since
2003, researchers have successfully transplanted stem cells into
damaged eyes to restore vision. Scientists are able to grow a thin
sheet of tot potent stem cells in the laboratory. When these sheets
are transplanted over the eye, the stem cells stimulate renewed
repair, eventually restoring vision. The latest development was in
2005, when researchers in England were able to restore the sight of
forty patients using the same technique. The group, led by Dr. Sheraz Daya, was able to successfully use adult stem cells obtained
from the patient, a relative, or even a
cadaver.
Further rounds of trials are ongoing.
• Balding:
Hair
follicles also contain stem cells, and some researchers predict
research on these follicle stem cells may lead to successes in
treating baldness through "hair multiplication," also known as "hair
cloning," as early as 2007. This treatment is expected to work
through taking stem cells from existing follicles, multiplying them
in cultures, and implanting the new follicles into the scalp.
• Potential benefits to gene therapy, blood transfusion, and
topical medicine
• Muscular Dystrophy:
Stem Cells Help Dogs
With MD
• Lou Gehrig's Disease
• Diabetes:
X-Cell
Center in Germany offering treatment,
7
Herbs that help,
Foods that cause diabetes,
Natural Herbal Cure for Diabetes,
http://www.scu.edu/ethics/publications/submitted/stem_cells.html.
Stem cells could also become a source
of kidney, nerve and heart muscle cells for people whose organs have
been damaged by the complications of diabetes.
• Parkinson's Disease
• Disc Degeneration:
Back pain costs the U.S. economy
over $50 billion annually and represents the second most common
reason for visits to a doctor. It is estimated that 10% of
50-year-old discs and 60% of 70-year-old discs are severely
degenerated. The patent application represents a potential
therapeutic breakthrough for patients worldwide who suffer from
chronic lumbar pain and related lower back disorders caused by disc
degeneration.
•
Hepatitis C, B, A:
Hepatitis Info & Treatment,
Clinically proven stem cell
treatment for Hepatitis & Cirrhosis
• AIDS
•
Leukemia,
Lymphoma, Myeloma, Myleodysplastic syndrome and other blood cancers:
Blood and Marrow Stem Cell Transplantation
• Chrohn's Disease
• ALS:
• Stroke:
Treatment
• Autism:
Treatment
"Scientists have found ways of developing
these stem cells into most types of human cells. Researchers are confident that
they will lead to treatments to many diseases:
bone loss, broken bones,
brain damage due to oxygen starvation,
severe burns,
cancer (some forms),
diabetes, Lou
Gehrig's disease, heart disease,
hepatitis, incomplete
bladder control, Huntington's,
leukemia, lupus,
muscular dystrophy,
multiple sclerosis, osteoarthritis,
Parkinson's,
spinal cord injuries, and
stroke! The Coalition for the
Advancement of Medical Research estimates that stem cell research
will develop cures and/or new treatments for 100 million Americans
who currently suffer from a wide variety of diseases and disorders."
Stem cells can be grown into any cell...
"Stem cells differ from other kinds of cells in the body. All stem
cells—regardless of their source—have three general properties: they are
capable of dividing and renewing themselves for long periods; they are
unspecialized; and they can give rise to specialized cell types.
One of the fundamental properties of a stem cell is that
it does not have any tissue-specific structures that allow it to perform
specialized functions. A stem cell cannot work with its neighbors to
pump blood through the body (like a heart muscle cell); it cannot carry
molecules of oxygen through the bloodstream (like a red blood cell); and
it cannot fire electrochemical signals to
other cells that allow the body to move or speak (like a nerve cell).
However, unspecialized stem cells can give rise to specialized cells,
including heart muscle cells, blood cells, or nerve cells.
Stem cells are capable of dividing and renewing
themselves for long periods. Unlike muscle
cells, blood cells, or nerve cells—which do not normally replicate
themselves—stem cells may replicate many times. When cells replicate
themselves many times over it is called proliferation. A starting
population of stem cells that proliferates for many months in the
laboratory can yield millions of cells. If the resulting cells continue
to be unspecialized, like the parent stem cells, the cells are said to
be capable of long-term self-renewal."
Amniotic Fluid
Derived Stem Cells
Can I Grow A New Brain?
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A summary
of cell-based therapies being tried now in people with spinal cord
injury around the world...
1.
Olfactory (nasal) Mucosa Autografts:
In 2001, Australia reported that nasal mucosa transplantation to injured
spinal cords stimulates regeneration in rats after spinal cord injury.
Dr. Carlos Lima and his colleagues in Lisbon, Portugal, have
transplanted nasal muce recovering some
function. Unfortunately, to date, there has not been a publication of
the results so that we do not know what proportion of the people recover
function, to what extent, and for how long. It is also unclear to me how
many people have received this procedure but it is probably over 3
dozen.
2.
Adult Olfactory Ensheating
Cell
Autografts: Dr. Mckay-Sims and his
colleagues in Brisbane, Australia, have managed to grow olfactory
ensheathing glia from the nasal mucosa of two patients and transplanted
these about 15 million of these cells into their spinal cords. The study
is still in its "double-blind" phase and we do not know whether there
has been recovery of function or not. In some ways, this is the most
desirable of all the options both from a scientific and clinical point
of view. The cells were grown from the nasal mucosa and have been
identified in culture as olfactory ensheathing glia. Because the cells
come from the same person, there should be less risk of immune rejection
of the cells.
3.
Fetal Olfactory Ensheathing Glial Transplants:
In Beijing, Dr. Hongyun Huang is transplanting fetal olfactory
ensheathing glia into the spinal cord of people who are 1-32 years after
injury. Over 500 people with spinal cord injury and perhaps another 200
people with other conditions (such as ALS and MS) have received these
transplants. The cells are injected into the spinal cord above and below
the injury site without cutting or removing part of the spinal cord. To
my knowledge, there has been three mortalities in the series, all in
people more than 3 months after surgery and from unrelated causes. The
cells are obtained from aborted fetuses and therefore are not
genetically matched to the person receiving it. Although there is some
evidence suggesting that fetal tissues are not rejected as adult
tissues, it is likely that these transplants will be rejected from the
spinal cord at some point, perhaps 3-4 months after transplantation.
Reports of earlier results in the first 171 patients that received such
transplants indicate an average of 4-8 dermatomes of sensory recovery
and 1-2 motor levels of improvement. Animal studies suggest that
olfactory ensheathing glia will migrate from the injection site into the
injury site and surrounding cord, change the environment of the injury
site, and promote regeneration of axons. Unfortunately, only about 10%
of the patients who have been transplanted week hospitalization.
Stem cell
treatment improves mobility after spinal cord injury: 5/11/2005
4.
Bone Marrow Stem
Cell
Auto-Grafts (Adult):
• Dr. Tarcisio Barros at the University of Sao Paulo in
Brazil has transplanted bone marrow mesenchymal
stem
cells into the spinal cord of about 30 patients with chronic spinal cord
injury. Some evidence from animal studies indicate that bone marrow
contain
stem
cells and that these cells can be persuaded to produce neurons in
culture. The cells were apparently injected through the vascular system
into the blood vessels of the spinal cord. Dr. Barros has reported some
initial promising results in terms of somatosensory evoked potential
improvement in the patients. It is not clear how much motor improvement
the patients are getting. Because the cells are auto grafts, they are
not likely to be rejected.
• Dr. Zhang at the Henan People's Provincial Hospital in
Zhengzhou, China said that he has transplanted bone marrow
stem
cells to dozens of people with spinal cord injury. The results are not
clear but they are looking for ways to improve the results. In January
2005, they have transplanted bone marrow
stem
cells into over 180 patients with strokes and spinal cord injury. They
grow the cells, sort them for those that are CD-43 positive, and then
transplant them into the spinal cord.
• There is a group of surgeons in Nanjing (China) that have
transplanted bone marrow
stem
cells into 90 patients with amyotrophic lateral sclerosis (ALS). These
cells were apparently directly transplanted into the brain and spinal
cord.
• There are also several reports of bone marrow
stem
cell
transplants being used in Italy to treat patients with amyotrophic
lateral sclerosis.
5.
Fetal Olfactory Ensheathing Glia and Neural
Stem
Cell
Transplants: Dr. Samuiel Rabinovich and
his colleagues in Novosibirsk have transplanted a mixture of olfactory
ensheathing glia and neural
stem
cells into the spinal cord of patients with chronic injuries. These
cells are apparently cultured from olfactory bulbs obtained from aborted
fetuses. They report improvements in motor and sensory function in the
patients. These results were published recently. It is not clear what
cells were being injected.
6.
Fetal Spinal Cord Transplants:
In the United States (Russia and Sweden as well), probably over 200
patients have received various fetal spinal cord transplants into the
injury site. The results have been published in a few papers but most of
the studies suggest modest recovery of function.
7.
Adult Schwann Cell
Auto-Grafts: Timothy Volmer
transplanted Schwann cells grown from peripheral nerves into two
patients with multiple sclerosis. Dr. Volmer has moved to Barrows
Neurological Institute in Phoenix, Arizona. A recent email suggested
that he has finally re-organized his team and will be starting his
clinical trials again. The trial at Yale University was funded by the
Myelin Project.
8.
Fetal Schwann Cell
Transplants: In Kunming, China,
neurosurgeons there have transplanted fetal Schwann cells from aborted
fetuses into about 90 patients with chronic spinal cord injury. They are
reporting some improvement in function although there is some skepticism
by visiting clinicians that these improvements are due to the
transplants or to decompressive surgery.
9.
Porcine Fetal Neural
Stem
Cell
Transplants: At the Washington
University in St. Louis and Albany Medical Center, 10 patients have
received transplants of neural
stem
cells obtained from fetal pig brains. This was in a clinical trial
sponsored by Diacrin. The cells are apparently grown from pig brain,
treated with antibodies to reduce the likelihood of immune rejection,
and then transplanted into the spinal cord. The results of this trial
have not yet been reported.
10.
Human Fetal Neural
Stem
Cell
Transplants: I have met several doctors
in China (Beijing and Guangzhou) who have grown human fetal neural
stem
cells from aborted fetuses and transplanted these into the spinal cords
of people with acute or chronic spinal cord injury. Apparently, these
patients have not gotten much recovery and most of these centers are no
longer transplanting these cells.
11.
Adult Activated Macrophage Auto-Grafts:
The company Proneuron carried out two phase 1 trials in Israel and in
Europe in patients that are within 2-3 weeks after spinal cord injury.
The cells were obtained from the blood of the patients, cultured and
activated on skin, and then transplanted into the spinal cord exposed by
laminectomy. This trial has started in the United States at three
centers: Craig Hospital in Denver, Kessler Rehabilitation Institute in
New Jersey, and Mt. Sinai Hospital in New York.
12.
Adult Peripheral Nerve Auto-Grafts:
• Dr. Carl Kao, a neurosurgeon who operates in Quito,
Ecuador, has transplanted peripheral nerves of about 600 patients over
the past 10-15 years. He also places omentum on the spinal cord which
apparently is causing epidural cyst formations in some patients. The
peripheral nerves should contain Schwann cells.
• Dr. Henreich Cheng, a neurosurgeon in Taiwan, has used
peripheral nerves to bridge transected spinal cords and treated with
several growth factors including basic fibroblast growth factor. In
1995, he published a widely recognized paper with Lars Olson, reporting
that axons will grow across the transection site and restore function.
Since returning to Taiwan, he has apparently carried out this procedure
in some patients. He has not yet published the results.
13.
Activated Macrophage Autografts:
In 1998, Michal Schwartz reported that activated macrophages improves
neurological recovery of rats after spinal cord injury. An Israeli
company called Proneuron initiated a phase 1 clinical trial to assess
this
treatment
in patients within 3 weeks after injury. Melissa Holly was the first
patient to undergo this therapy about 3 years ago. She showed
substantial improvement. Perhaps a quarter of the patients who received
the
treatment
showed improvement. A new phase 2 clinical trial is about read to start.
14.
Omentum Transplant:
In the 1980's, Dr. Harry Goldsmith began transposing omentum to the
spinal cord of animals. The omentum is a part of the vascular tissue
that surrounds the stomach and intestines. It's job is too carry blood
to and food from the gut. Dr. Goldsmith and colleagues transferred the
omentum to many patients over the past two decades. In addition, Dr.
Carl Kao does omentum transplant.
15.
Umbilical Cord Blood Transplants:
There was a news report from Korea of a woman who recovered motor
function after having received an umbilical cord blood
stem
cell
transplant. The cells came from an umbilical cord blood bank, matched
with the recipient, and then cultured to select for certain cells. The
results have not yet been published. There are persistent news reports
that Biomark International, a company that was shut down by the FDA and
has now moved to London, has infused umbilical cord blood cells into
hundreds of patients, some of whom may have spinal cord injury. There
are also reports that of umbilical cord blood
cell
transplants being done in Mexico.
Young, Wise. "A summary of cell-based
therapies being tried now in people with spinal cord injury around the
world ." CareCure Community. 16 July 2004. Web. 20 April 2007.
http://sci.rutgers.edu/forum/showthread.php?t=19719.
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Reset on February 5, 2011
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