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[Music]
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stem cells the secret to
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immortality over the years there have
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been many advances in the field of
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medicine that have helped to extend the
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longev ity of
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mankind some of which would have been
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considered to be too fantastic to
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comprehend even just three decades ago
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one of these modern Miracles are the
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advances and strides taken in the area
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of stem cell research some even consider
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stem cells to be one of the possible
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secrets of
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mortality stem cells are cells that can
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differentiate into other types of cells
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and can also divide in self renewal to
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produce more of the same type of stem
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cells in mammals there are two broad
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types of stem cells embryonic stem cells
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which are isolated from the Inner Cell
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mass of blasto cysts in early embryonic
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development and adult stem cells which
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are found in various tissues of fully
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developed mammals in adult organisms
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stem cells and progenitor cells act as a
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repair system for the body replenishing
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adult tissues in a developing embryo
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stem cells can differentiate into all
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the specialized cells ectoderm endoderm
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and mism but also maintain the normal
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turnover of regenerative organs such as
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blood skin or intestinal tissues there
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are three known accessible sources of
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orious adult stem cells in humans bone
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marrow adipose tissue and blood stem
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cells can also be taken from umbilical
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cord blood just after birth of all stem
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cell therapy types autolus harvesting
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involves the least
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risk adult stem cells are frequently
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used in various medical therapies such
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as bone marrow
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transplantation stem cells can now be
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artificially grown and transformed and
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differentiated into specialized cell
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types with characteristics consistent
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with cells of various tissues such as
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muscles or nerves embryonic cell lines
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and autologous embryonic stem cells
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generated through somatic cell nuclear
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transfer or dedifferentiation have also
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been proposed as promising candidates
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for future therapies Research into stem
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cells grew out of findings by Ernest a
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mccullock and James E till at the
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University of Toronto in the
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1960s the classical definition of a stem
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cell requires that it possesses two
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properties self-renewal the ability to
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go through numerous cycles of cell
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division while maintaining the
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undifferentiated state potency
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the capacity to differentiate into
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specialized cell types in the strictest
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sense this requires stem cells to be
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either totipotent or plottin to be able
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to give rise to any mature cell type
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although multipotent or unipotent
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progenitor cells are sometimes referred
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to as stem cells apart from this it is
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said that stem cell function is
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regulated in a feedback mechanism two
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mechanisms ensure that a stem cell
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population is maintained
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one obligatory asymmetric replication a
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stem cell divides into one Mother cell
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that is identical to the original stem
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cell and another daughter cell that is
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differentiated when a stem cell
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self-renews it divides and does not
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disrupt the undifferentiated state this
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self-renewal demands control of cell
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cycle as well as upkeep of multipotency
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or pipany which all depends on the stem
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cell two stochastic
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differentiation when one stem cell
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develops into two differentiated
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daughter cells another stem cell
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undergoes mitosis and produces two stem
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cells identical to the original
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pluripotent embryonic stem cells
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originate as Inner Cell mass or ICM for
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short cells within a blast assy these
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stem cells can become any tissue in the
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body excluding a placenta only cells
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from an earlier stage of the embryo
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known as the marula AR totipotent able
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to become all tissues in the body and
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the extra embryonic
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placenta human embryonic stem cells a
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stem cell colonies that are not yet
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differentiated B nerve cells an example
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of a cell type after
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differentiation potency specifies the
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differentiation potential meaning the
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potential to differentiate into
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different cell types of the stem cell
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totipotent or omnipotent stem cells can
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differentiate into embryonic and
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extraembryonic cell types such cells can
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construct a complete viable organism
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these cells are produced from the fusion
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of an egg and a sperm cell cells
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produced by the first few divisions of
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the fertilized egg are also
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totipotent pluripotent stem cells are
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the descendants of totipotent cells and
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can differentiate into nearly all cells
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cells derived from any of the three germ
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layers
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multipotent stem cells can differentiate
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into a number of cell types but only
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those of a closely related family of
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cells oligopotent stem cells can
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differentiate into only a few cell types
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such as lymphoid or myoid stem cells
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unipotent cells can produce only one
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cell type their own but have the
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property of self-renewal which
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distinguishes them from non- stem cells
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such as progenitor cells which cannot
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self-renew in in practice stem cells are
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identified by whether they can
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regenerate tissue for example the
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defining test for bone marrow or
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hematopoetic stem cells or hsc's for
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short is the ability to transplant the
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cells and save an individual without
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hsc's this demonstrates that the cells
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can produce new blood cells over a long
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term it should also be possible to
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isolate stem cells from the transplanted
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individual which can themselves be
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transplanted into another IND individual
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without hsc's demonstrating that the
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stem cell was able to
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self-renew properties of stem cells can
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be Illustrated in vitro using methods
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such as clonogenic assays in which
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single cells are assessed for their
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ability to differentiate and
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self-renew stem cells can also be
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isolated by their possession of a
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distinctive set of cell surface
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markers however invitro culture
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conditions can alter the behavior of
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cells making it unclear whether the
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cells shall behave in a similar manner
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in
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Vivo there is considerable debate as to
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whether some proposed adult cell
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populations are truly stem
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cells embryonic stem cells also known as
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esc's are the cells of the Inner Cell
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mass of a blast assyst formed prior to
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implantation in the uterus in human
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embryonic development the blasticus
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stage is reached 4 to 5 days after
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fertilization at which time it can of 50
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to 150 cells esc's are pluripotent and
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give rise during development to all
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derivatives of the three germ layers
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ectoderm endoderm and mism in other
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words they can develop into each of the
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more than 200 cell types of the adult
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body when given sufficient and necessary
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stimulation for a specific cell type
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they do not contribute to the extra
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embrionic membranes or to the
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placenta during embryonic development
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the cells of the Inner Cell Mass
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continuously divide and become more
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specialized for example a portion of the
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ectoderm in the dorsal part of the
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embryo specializes as neurectoderm which
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will become the future central nervous
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system later in development neurulation
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causes the neurectoderm to form the
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neural tube at the neural tube stage the
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anterior portion undergoes eniz to
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generate or pattern the basic form of
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the brain
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at this stage of development the
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principal cell type of the CNS is
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considered a neural stem
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cell the neural stem cells self-renew
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and at some point transition into radial
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gal progenitor cells also known as
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rgps early formed rgps self-renew by
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symmetrical division to form a reservoir
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group of progenitor
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cells these cells transition to a
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neurogenic State and start to divide
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asymmetrically to produce a large
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diversity of many different neuron types
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each with unique gene expression
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morphological and functional
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characteristics the process of
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generating neurons from radial gal cells
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is called
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neurogenesis the radial gal cell has a
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distinctive bipolar morphology with
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highly elongated processes spanning the
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thickness of the neural tube wall it
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shares some gal characteristics most
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notably the expression of gal fibular
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acidic protein or gfap for
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short the radial gal cell is the primary
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neural stem cell of the developing
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vertebrate CNS and its cell body resides
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in the ventricular Zone adjacent to the
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developing ventricular system neural
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stem cells are committed to the neuronal
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lineages such as neurons astrocytes and
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oligodendrocytes and thus their potency
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is
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restricted nearly all research to date
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has made use of Mouse embryonic stem
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cells or human embryonic stem cells
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derived from the early Inner Cell Mass
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both have the essential stem cell
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characteristics yet they require very
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different environments in order to
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maintain an undifferentiated State Mouse
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embrionic stem cells are grown on a
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layer of gelatin as an extracellular
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Matrix for support and require the
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presence of leukemia inhibitory factor
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in serum media a drug cocktail
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containing Inhibitors called 2i has also
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been shown to maintain pipany in stem
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cell
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culture human esc's are grown on a feed
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delayer of mouse embryonic fibr blasts
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and require the presence of basic fibr
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blast growth factor without optimal
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culture conditions or genetic
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manipulation embryonic stem cells will
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rapidly
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differentiate a human embryonic stem
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cell is also defined by the expression
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of several transcription factors and
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cell surface protein
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the transcription factors OCT 4 nanog
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and Sox 2 form the core regulatory
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Network that ensures the suppression of
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genes that lead to differentiation and
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the maintenance of
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pluripotency the cell surface antigens
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most commonly used to identify hes cells
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are the glycolipids stage specific
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embryonic antigen 3 and four and the
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Keratin sulfate antigens TR 160 and TR
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181
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the molecular definition of a stem cell
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includes many more proteins and
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continues to be a topic of
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research by using human embryonic stem
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cells to produce specialized cells like
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nerve cells or heart cells in the lab
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scientists can gain access to adult
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human cells without taking tissue from
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patients they can then study these
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specialized adult cells in detail to try
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to discern complications of diseases or
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to study cell reactions to propos new
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drugs because of their combined
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abilities of unlimited expansion and
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pipany embryonic stem cells remain a
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theoretically potential source for
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regenerative medicine and tissue
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replacement after injury or disease
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however there are currently no approved
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treatments using ES cells the first
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human trial was approved by the US Food
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and Drug Administration in January 2009
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however the human trial was not
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initiated until October the 13th 2010 in
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Atlanta for spinal cord injury research
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on November 14th 2011 the company
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conducting the trial Geron Corporation
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announced that it will discontinue
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further development of its stem cell
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programs differentiating es cells into
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usable cells while avoiding transplant
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rejection are just a few of the hurdles
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that embryonic stem cell researchers
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still face embryonic stem cells being
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pluripotent require specific signals for
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direct differentiation if injected
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directly into another body es cells will
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differentiate into many different types
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of cells causing a
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Teratoma ethical considerations
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regarding the use of unborn human tissue
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are another reason for the lack of
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approved treatments using embryonic stem
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cells many nations currently have
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moratoria or limitations on either human
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es cell research or the production of
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new human es cell
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lines the Primitive stem cell cells
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located in the organs of fetuses are
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referred to as fetal stem cells there
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are two types of fetal stem cells fetal
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proper stem cells come from the tissue
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of the fetus proper and are generally
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obtained after an abortion these stem
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cells are not Immortal but have a high
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level of division and are
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multipotent extraembryonic fetal stem
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cells come from extra embrionic
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membranes and are generally not
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distinguished from adult stem cells
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these stem cells are acquired after
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birth they are not Immortal but have a
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high level of cell division and are
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pluripotent stem cell division and
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differentiation adult stem cells also
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called somatic stem cells are stem cells
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which maintain and repair the tissue in
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which they are found they can be found
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in children as well as adults there are
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three known accessible sources of
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autologous adult stem cells in
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humans bone marrow which require
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extraction by harvesting that is
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drilling into bone typically the femur
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or iliac crest fat cells known as
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adipose tissue which requires extraction
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by
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liposuction blood which requires
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extraction through a feris wherein blood
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is drawn from the donor similar to a
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blood donation and pass through a
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machine that extracts the stem cells and
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returns other portions of the blood to
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the
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donor stem cells can also be taken from
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umbilical cord blood just after birth of
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all stem cell types autolus harvesting
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involves the least Risk by definition
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autolus cells are obtained from one's
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own body just as one may Bank his or her
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own blood for elective surgical
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procedures plent adult stem cells are
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rare and generally small in number but
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they can be found in umbilical cord
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blood and other
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tissues bone marrow is a rich source of
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adult stem cells which have been used in
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treating several conditions including
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liver curosis chronic limb ischemia and
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endstage heart failure the quantity of
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bone marrow stem cells declines with age
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and is greater in males than females
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during reproductive years much adult
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stem cell researched to date has aimed
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to characterize their potency and
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self-renewal
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capabilities DNA damage accumulates with
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age in both stem cells and the cells
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that comprise the stem cell environment
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this accumulation is is considered to be
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responsible at least in part for
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increasing stem cell dysfunction with
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aging known as the DNA damage Theory of
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Aging the DNA damage Theory of Aging
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proposes that aging is a consequence of
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unrepaired accumulation of naturally
00:16:15
occurring DNA damages damage in this
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context is a DNA alteration that has an
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abnormal structure although both
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mitochondrial and nuclear DNA damage can
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contribute to aging nuclear DNA DNA is
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the main subject of this
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analysis nuclear DNA damage can
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contribute to aging either indirectly by
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increasing apoptosis or Celia cence or
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directly by increasing cell
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dysfunction several review articles have
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shown that deficient DNA repair allowing
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greater accumulation of DNA damages
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causes premature aging and that
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increased DNA repair facilitates greater
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longevity Mouse models of nucleotide
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Excision repair syndromes reveal a
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striking correlation between the degree
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to which specific DNA repair pathways
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are compromised and the severity of
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accelerated aging strongly suggesting a
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causal
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relationship human population studies
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show that single nucleotide
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polymorphisms in DNA repair genes
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causing upregulation of their expression
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correlate with increases in
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longevity Lombard etal compiled a
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lengthy list of mouse mutation models
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with patholog IC features of premature
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aging all caused by different DNA repair
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defects freas and de magal haes
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presented a comprehensive review and
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Appraisal of the DNA damaged Theory of
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Aging including a detailed analysis of
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many forms of evidence linking DNA
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damage to aging as an example they
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described a study showing that
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centenarians of 100 to7 years of age had
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higher levels of two DNA repair enzymes
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pop 1 and K u70 than general population
00:18:01
old individuals of 69 to 75 years of age
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their analysis supported the hypothesis
00:18:07
that improved DNA repair leads to longer
00:18:11
lifespan overall they concluded that
00:18:13
while the complexity of responses to DNA
00:18:16
damage remains only partly understood
00:18:18
the idea that DNA damage accumulation
00:18:21
with age is the primary cause of Aging
00:18:23
remains an intuitive and Powerful
00:18:26
one in humans and other mammals DNA
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damage occurs frequently and DNA repair
00:18:32
processes have evolved to
00:18:34
compensate in estimates made for mice
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DNA lesions occur on average 25 to 115
00:18:41
times per minute in each cell or about
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36,000 to 160,000 per cell per day some
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DNA damage May remain in any cell
00:18:52
despite the action of repair
00:18:54
processes the accumulation of unrepaired
00:18:57
DNA damage is more prevalent in certain
00:18:59
types of cells particularly in
00:19:02
non-replicating or slowly replicating
00:19:04
cells such as cells in the brain
00:19:06
skeletal and cardiac muscle most adult
00:19:10
stem cells are lineage restricted
00:19:12
multipotent and are generally referred
00:19:15
to by their tissue origin mimal stem
00:19:18
cell adpost derived stem cell
00:19:20
endothelium stem cell Dental pulp stem
00:19:23
cell
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Etc mu cells multi-lineage differenti I
00:19:28
ating stress enduring cells are a
00:19:30
recently discovered plottin stem cell
00:19:33
type found in multiple adult tissues
00:19:36
including adipose dermal fibr blasts and
00:19:39
bone marrow while rare Muse cells are
00:19:42
identifiable by their expression of
00:19:45
ssa3 a marker for undifferentiated stem
00:19:48
cells and general meenal stem cells
00:19:51
markers such as
00:19:53
cd105 when subjected to single cell
00:19:56
suspension culture the cells will
00:19:58
generate clusters that are similar to
00:20:00
embryoid bodies in morphology as well as
00:20:03
gene expression including canonical
00:20:05
pipany markers OCT 4 sock 2 and
00:20:09
nanog adult stem cell treatments have
00:20:12
been successfully used for many years to
00:20:14
treat leukemia and related bone and
00:20:16
blood cancers through bone marrow
00:20:19
transplants adult stem cells are also
00:20:21
used in veterinary medicine to treat
00:20:24
tendon and ligament injuries in
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horses the use of adult stem cells in
00:20:29
research and therapy is not as
00:20:31
controversial as the use of embryonic
00:20:33
stem cells because the production of
00:20:35
adult stem cells does not require the
00:20:37
destruction of an
00:20:38
embryo additionally in instances where
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adult stem cells are obtained from the
00:20:43
intended recipient an autographed the
00:20:46
risk of rejection is essentially
00:20:48
non-existent consequently more US
00:20:51
Government funding is being provided for
00:20:53
adults them cell
00:20:55
research with the increasing demand of
00:20:58
human adult adult stem cells for both
00:20:59
research and clinical purposes typically
00:21:02
1 to 5 million cells per kilo of body
00:21:05
weight are required per treatment it
00:21:07
becomes of utmost importance to bridge
00:21:09
the gap between the need to expand the
00:21:11
cells in vitro and the capability of
00:21:14
harnessing the factors underlying
00:21:16
replicative
00:21:17
senance adult stem cells are known to
00:21:20
have a limited lifespan in vitro and to
00:21:22
enter replicative senance almost
00:21:24
undetectably upon starting in vitro
00:21:27
culturing
00:21:29
multipotent stem cells are also found in
00:21:31
amniotic fluid these stem cells are very
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active expand extensively without
00:21:37
feeders and are not
00:21:39
tumorogenic amniotic stem cells are
00:21:42
multipotent and can differentiate in
00:21:44
cells of adipogenic osteogenic myogenic
00:21:48
endothelial hepatic and also neuronal
00:21:51
lines amniotic stem cells are a topic of
00:21:54
active
00:21:56
research use of stem cells from amniotic
00:21:59
fluid overcomes the ethical objections
00:22:01
to using human embryos as a source of
00:22:04
cells Roman Catholic teaching forbids
00:22:07
the use of embryonic stem cells in
00:22:09
experimentation accordingly the Vatican
00:22:11
newspaper OB servator Romano called
00:22:15
amniotic stem cells the future of
00:22:17
medicine it is possible to collect
00:22:20
amniotic stem cells for donors or for
00:22:22
autologous use the first US amniotic
00:22:25
stem cells Bank was opened in 2009 9 in
00:22:29
Medford Massachusetts by biocells Center
00:22:32
Corporation and collaborates with
00:22:34
various hospitals and universities all
00:22:36
over the world adult stem cells have
00:22:39
limitations with their potency unlike
00:22:41
embryonic stem cells known as esc's they
00:22:44
are not able to differentiate into cells
00:22:47
from all three germ layers as such they
00:22:50
are deemed
00:22:51
multipotent however reprogramming allows
00:22:54
for the creation of plottin cells
00:22:56
induced plottin stem cells from adult
00:22:59
cells these are not adult stem cells but
00:23:02
adult cells reprogrammed to give rise to
00:23:05
cells with plottin
00:23:07
capabilities using genetic reprogramming
00:23:10
with protein transcription factors
00:23:12
plottin stem cells with ESC like
00:23:14
capabilities have been derived the first
00:23:17
demonstration of induced plottin stem
00:23:19
cells was conducted by shinya yamanaka
00:23:22
and his colleagues at Kyoto University
00:23:25
they used the transcription factors OCT
00:23:27
3 and 4 sock 2 C myc and klf4 to
00:23:33
reprogram Mal's fiberblast cells into
00:23:35
plottin cells subsequent work used these
00:23:39
factors to induce pipany in human
00:23:42
fiberblast cells yuning Yu James
00:23:45
Thompson and their colleagues at the
00:23:47
University of Wisconsin Madison used a
00:23:50
different set of factors OG for socks 2
00:23:53
nanog and Lin 28 and carried out their
00:23:56
experiments using cells from Human
00:23:59
foreskin however they were able to
00:24:01
replicate yamanaka's finding that
00:24:03
inducing pipany in human cells was
00:24:07
possible induced plottin stem cells
00:24:10
known as ipscs for short differ from
00:24:13
embryonic stem cells they share many
00:24:16
similar properties such as pipany and
00:24:19
differentiation potential the expression
00:24:21
of pipany genes epigenetic patterns
00:24:24
embryoid body and teratoma formation and
00:24:27
viable Chimera formation but there are
00:24:30
many differences within these
00:24:32
properties the chromatin of ipscs
00:24:35
appears to be more closed or methylated
00:24:38
than that of
00:24:39
esc's similarly the gene expression
00:24:42
pattern between esc's and ipscs or even
00:24:46
ipscs sourced from different Origins
00:24:49
there are thus questions about the
00:24:50
completeness of reprogramming and the
00:24:53
sematic memory of induced ppant stem
00:24:55
cells despite this inducing a adult
00:24:58
cells to be pipitantv
00:25:01
as a result of the success of these
00:25:04
experiments Ian wilou who helped create
00:25:07
the first cloned animal Dolly the sheep
00:25:09
has announced that he will abandon
00:25:11
sematic cell nuclear transfer as an
00:25:13
Avenue of research furthermore induced
00:25:16
pluripotent stem cells provide several
00:25:19
therapeutic advantages like esc's they
00:25:21
are pluripotent they thus have great
00:25:24
differentiation potential theoretically
00:25:27
they could produce any sub within the
00:25:28
human body if reprogramming to pipany
00:25:31
was
00:25:32
complete moreover unlike esc's they
00:25:36
potentially could allow doctors to
00:25:37
create a pipan stem cell line for each
00:25:40
individual patient Frozen blood samples
00:25:43
can be used as a valuable source of
00:25:45
induced pipitantv
00:25:58
use therapeutically ipscs hold create
00:26:01
potential for future use in medical
00:26:03
treatment and
00:26:05
research to ensure self-renewal stem
00:26:08
cells undergo two types of cell division
00:26:11
symmetric division gives rise to two
00:26:14
identical daughter cells both endowed
00:26:16
with stem cell properties asymmetric
00:26:19
division on the other hand produces only
00:26:21
one stem cell and a progenitor cell with
00:26:23
limited self-renewal potential
00:26:26
progenitors can go through several round
00:26:28
of cell division before terminally
00:26:30
differentiating into a mature cell it is
00:26:33
possible that the molecular distinction
00:26:35
between symmetric and asymmetric
00:26:37
divisions lies in differential
00:26:39
segregation of cell membrane proteins
00:26:41
such as receptors between the daughter
00:26:44
cells an alternative theory is that stem
00:26:47
cells remain undifferentiated due to
00:26:50
environmental cues in their particular
00:26:52
Niche stem cells differentiate when they
00:26:55
leave that Niche or no longer receive
00:26:57
those signals
00:26:59
studies in dropil garum have identified
00:27:02
the signals decapentaplegic and
00:27:04
adherence Junctions that prevent jarum
00:27:07
stem cells from
00:27:08
differentiating stem cell therapy is the
00:27:11
use of stem cells to treat or prevent a
00:27:13
disease or condition bone marrow
00:27:16
transplant is a form of stem cell
00:27:18
therapy that has been used for many
00:27:19
years without
00:27:21
controversy stem cell treatments May
00:27:24
lower symptoms of the disease or
00:27:26
condition that's being treated the
00:27:28
lowering of symptoms may allow patients
00:27:30
to reduce the drug intake of the disease
00:27:32
or condition stem cell treatment may
00:27:35
also provide knowledge for society to
00:27:37
further stem cell understanding and
00:27:39
future
00:27:40
treatments stem cell treatments may
00:27:42
require immunosuppression because of a
00:27:44
requirement for radiation before the
00:27:46
transplant to remove the person's
00:27:48
previous cells or because the patient's
00:27:51
immune system May Target the stem cells
00:27:54
one approach to avoid the second
00:27:56
possibility is to use stem cells from
00:27:57
the same patient who is being
00:28:00
treated pipany in certain stem cells
00:28:03
could also make it difficult to obtain a
00:28:05
specific cell type it is also difficult
00:28:08
to obtain the exact cell type needed
00:28:10
because not all cells in a population
00:28:12
differentiate
00:28:14
uniformly undifferentiated cells can
00:28:16
create tissues other than desired
00:28:19
types some stem cells form tumors after
00:28:22
transplantation pipany is linked to
00:28:25
tumor formation especially in embryonic
00:28:27
stem cell cells fetal proper stem cells
00:28:30
induced plur repetent stem cells fetal
00:28:33
proper stem cells form tumors despite
00:28:36
multipotency
00:28:37
some of the fundamental patents covering
00:28:40
human embryonic stem cells are owned by
00:28:42
the Wisconsin alumni Research Foundation
00:28:45
known as Warf they are patents 5843
00:28:50
780
00:28:53
62086 and 7029 913 invent by James A
00:28:59
Thompson Warf does not enforce these
00:29:02
patents against academic scientists but
00:29:04
does enforce them against
00:29:07
companies in 2006 a request for the US
00:29:11
PTO the US patent and trademark office
00:29:14
to reexamine the three patents was filed
00:29:16
by the public patent foundation on
00:29:18
behalf of its client the nonprofit
00:29:20
patent Watchdog group consumer Watchdog
00:29:23
formerly the foundation for taxpayer and
00:29:25
consumer rights in the reexamination
00:29:29
process which involves several rounds of
00:29:31
discussion between the US PTO and the
00:29:33
parties the US PTO initially agreed with
00:29:36
consumer Watchdog and rejected all the
00:29:38
claims in all three
00:29:40
patents however in response Warf amended
00:29:43
the claims of all three patents to make
00:29:45
them more narrow and in 2008 the US PTO
00:29:49
found the amended claims in all three
00:29:51
patents to be
00:29:52
patentable the decision on one of the
00:29:55
patents was appealable while the
00:29:56
decisions on the other two were not
00:29:59
consumer Watchdog appealed the granting
00:30:01
of the 913 patent to the uspto's board
00:30:04
of patent appeals and interferences
00:30:07
which granted the appeal and in 2010 the
00:30:10
bpai decided that the amended claims of
00:30:12
the 913 patent were not
00:30:16
patentable however WF was able to reopen
00:30:19
prosecution of the case and did so
00:30:21
amending the claims of the 913 patent
00:30:23
again to make them more narrow and in
00:30:26
January 2013 the amend claims were
00:30:30
allowed in July 2013 Consumer Watchdog
00:30:34
announced that it would appeal the
00:30:35
decision to allow the claims of the 913
00:30:38
patent to the US court of appeals for
00:30:40
the federal circuit the federal appeals
00:30:42
court that his patent cases at a hearing
00:30:45
in December 2013 the cafc raised the
00:30:49
question of whether consumer Watchdog
00:30:51
had legal standing to appeal the case
00:30:53
could not proceed until the issue was
00:30:55
resolved
00:30:58
diseases and conditions where stem cell
00:31:00
treatment is being investigated include
00:31:03
diabetes rheumatoid arthritis
00:31:06
Parkinson's disease Alzheimer's disease
00:31:10
osteoarthritis stroke and traumatic
00:31:12
brain injury repair learning disability
00:31:15
due to congenital disorder spinal cord
00:31:18
injury repair heart
00:31:21
inunction anti-cancer treatments
00:31:24
boldness reversal replace missing teeth
00:31:27
repair repair hearing restore vision and
00:31:30
repair damage to the cornea amyotrophic
00:31:33
lateral sclerosis Crohn's disease wound
00:31:37
healing male infertility due to absence
00:31:40
of spermatogonial stem cells in recent
00:31:44
studies scientists have found a way to
00:31:46
solve this problem by reprogramming a
00:31:48
cell and turning it into a spermato Zone
00:31:51
other Studies have proven the
00:31:52
restoration of spermatogenesis by
00:31:55
introducing human ipsc cells in mice
00:31:58
testicles this could mean the end of aus
00:32:02
spermia female infertility oyes made
00:32:06
from embryonic stem cells recently
00:32:09
scientists have found the ovarian stem
00:32:11
cells a rare type of cells found in the
00:32:13
ovary it is not clear their existence
00:32:16
yet but the impact it could have are
00:32:18
Limitless it could be used as a
00:32:20
treatment not only for infertility but
00:32:23
also for premature ovarian
00:32:26
insufficiency as with any radical
00:32:28
advances in science the research into
00:32:30
stem cell treatment has not been without
00:32:33
controversy the stem cell controversy is
00:32:35
the consideration of the ethics of
00:32:37
research involving the development use
00:32:39
and destruction of human embryos most
00:32:42
commonly this controvery focuses on
00:32:44
embryonic stem cells not all stem cell
00:32:47
research involves human embryos for
00:32:50
example adult stem cells amniotic stem
00:32:53
cells and induced plottin stem cells do
00:32:56
not involve creating using or destroying
00:32:59
human embryos and thus are minimally if
00:33:02
at all
00:33:03
controversial many less controversial
00:33:06
sources of acquiring stem cells include
00:33:08
using cells from the umbilical cord
00:33:10
breast milk and bone marrow which are
00:33:12
not
00:33:14
plottin great levels of success and
00:33:17
potential have been realized from
00:33:18
research using adult stem cells in early
00:33:22
2009 the FDA approved the first human
00:33:25
clinical trials using embryonic stem
00:33:27
cells C only cells from an embryo at the
00:33:30
morula stage or earlier are truly
00:33:32
totipotent meaning that they are able to
00:33:34
form all cell types including placental
00:33:37
cells adult stem cells are generally
00:33:40
limited to differentiating into
00:33:42
different cell types of their tissue of
00:33:44
origin however some evidence suggests
00:33:47
that adult stem cell plasticity may
00:33:49
exist increasing the number of cell
00:33:51
types a given adult stem cell can
00:33:54
become many of the debates surrounding
00:33:57
human EMB I IC stem cells concern issues
00:33:59
such as what restriction should be made
00:34:01
on studies using these types of cells at
00:34:05
what point does one consider life to
00:34:07
begin is it just to destroy an embryo
00:34:09
cell if it has the potential to cure
00:34:11
countless numbers of patients political
00:34:14
leaders are debating how to regulate and
00:34:17
fund research studies that involve the
00:34:19
techniques used to remove the embryo
00:34:21
cells no clear consensus has emerged
00:34:25
other recent discoveries May extinguish
00:34:27
the need need for embryonic stem
00:34:30
cells much of the criticism has been a
00:34:32
result of religious beliefs and in the
00:34:34
most high-profile case US President
00:34:37
George W Bush signed an executive order
00:34:40
Banning the use of federal funding for
00:34:42
any cell lines other than those already
00:34:44
in existence stating at the time my
00:34:47
position on these issues is shaped by
00:34:49
deeply held beliefs and I also believe
00:34:53
human life is a sacred gift from our
00:34:56
creator this B was in part revoked by
00:34:59
his successor Barack Obama who stated as
00:35:02
a person of faith I believe we are
00:35:04
called to care for each other and work
00:35:06
to ease human suffering I believe we
00:35:09
have been given the capacity and will to
00:35:11
pursue this research and the humanity
00:35:13
and conscience to do so
00:35:16
responsibly some stem cell researchers
00:35:18
are working to develop techniques of
00:35:20
isolating stem cells that are as potent
00:35:22
as embryonic stem cells but do not
00:35:25
require a human
00:35:26
embryo foremost among these was the
00:35:29
discovery in August 2006 that adult
00:35:32
cells can be reprogrammed in a plottin
00:35:34
state by the introduction of four
00:35:36
specific transcription factors resulting
00:35:39
in induced plottin stem cells this major
00:35:42
breakthrough won a Nobel prize for the
00:35:45
discoverers shinya yamanaka and John
00:35:49
giran in an alternative technique
00:35:51
researchers at Harvard University led by
00:35:54
Kevin Egan and citri marage have
00:35:56
transferred the new nucleus of a sematic
00:35:58
cell into an existing embryonic stem
00:36:01
cell thus creating a new stem cell
00:36:04
line researchers at Advanced cell
00:36:06
technology led by Robert Lanza and
00:36:09
Travis Wall reported the successful
00:36:11
derivation of a stem cell line using a
00:36:13
process similar to pre-implantation
00:36:16
genetic diagnosis in which a single
00:36:18
blastomere is extracted from a blast
00:36:21
assy at the 2007 meeting of the
00:36:24
international Society for stem cell
00:36:26
research the ISS CR Lanza announced that
00:36:29
his team had succeeded in producing
00:36:31
three new stem cell lines without
00:36:33
destroying the parent embryos these are
00:36:36
the first human embryonic cell lines in
00:36:38
existence that didn't result from the
00:36:40
destruction of an
00:36:42
embryo Lanza is currently in discussions
00:36:44
with the National Institutes of Health
00:36:46
to determine whether the new techniqu
00:36:48
sidesteps US restrictions on federal
00:36:51
funding for ES cell
00:36:53
research Antony tler of Wake Forest
00:36:56
University says the fluid surrounding
00:36:58
the fetus has been found to contain stem
00:37:00
cells that when used correctly can be
00:37:03
differentiated towards cell types such
00:37:05
as fat bone muscle blood vessel nerve
00:37:08
and liver cells the extraction of this
00:37:11
fluid is not thought to harm the fetus
00:37:13
in any way he hopes that these cells
00:37:16
will provide a valuable resource for
00:37:18
tissue repair and for engineered organs
00:37:21
as
00:37:22
well stem cell debates have motivated
00:37:25
and reinvigorated the pro-life movement
00:37:27
whose members are concerned with the
00:37:29
rights and status of the embryo as an
00:37:31
early AED human life they believe that
00:37:34
embryonic stem cell research profits
00:37:36
from and violates the sanctity of life
00:37:39
and is tantamount to murder the
00:37:41
fundamental assertion of those who
00:37:43
oppose embryonic stem cell research is
00:37:45
the belief that human life is inviolable
00:37:48
combined with the belief that human life
00:37:50
begins when a sperm cell fertilizes an
00:37:52
egg cell to form a single cell the view
00:37:55
of those in favor is that these embryos
00:37:58
would otherwise be discarded and if used
00:38:00
as stem cells they can survive as part
00:38:02
of a living human
00:38:05
being a portion of stem cell researchers
00:38:07
use embryos that were created but not
00:38:10
used in invitro fertility treatments to
00:38:12
derive new stem cell lines most of these
00:38:15
embryos are to be destroyed or stored
00:38:18
for long periods of time long past their
00:38:20
viable storage life in the United States
00:38:23
alone an estimated at least 400,000 such
00:38:27
em OS exist this has led to some
00:38:29
opponents of abortion such as Senator
00:38:32
Orin hatch to support human embryonic
00:38:34
stem cell
00:38:36
research medical researchers widely
00:38:38
report that stem cell research has the
00:38:40
potential to dramatically alter
00:38:42
approaches to understanding and treating
00:38:44
diseases and to alleviate suffering in
00:38:48
the future most medical researchers
00:38:50
anticipate being able to use
00:38:51
Technologies derived from stem cell
00:38:53
research to treat a variety of diseases
00:38:56
and impairments
00:38:58
spinal cord injuries and Parkinson's
00:39:00
disease are two examples that have been
00:39:02
championed by high-profile media
00:39:04
personalities for instance Christopher
00:39:06
reev and Michael J fox who have lived
00:39:09
with these conditions
00:39:11
respectively the anticipated medical
00:39:13
benefits of stem cell research add
00:39:15
urgency to the debates which has been
00:39:17
appealed to by proponents of embryonic
00:39:19
stem cell
00:39:21
research in August 2000 the US National
00:39:25
Institutes of Health's guidelines stated
00:39:28
research involving human pluripotent
00:39:30
stem cells promises new treatments and
00:39:33
possible cures for many debilitating
00:39:35
diseases and injuries including
00:39:37
Parkinson's disease diabetes heart
00:39:40
disease multiple sclerosis Burns and
00:39:42
spinal cord
00:39:44
injuries the NIH believes the potential
00:39:47
medical benefits of human plottin stem
00:39:49
cell technology are compelling and
00:39:51
worthy of pursuit in accordance with
00:39:53
appropriate ethical
00:39:55
standards in 2006 researchers at
00:39:59
Advanced cell technology of Worcester
00:40:01
Massachusetts succeeded in obtaining
00:40:03
stem cells from Mouse embryos without
00:40:06
destroying the embryos if this technique
00:40:09
and its reliability are improved it
00:40:11
would alleviate some of the ethical
00:40:12
concerns related to embryonic stem cell
00:40:16
research another technique announced in
00:40:18
2007 may also diffuse the long-standing
00:40:21
debate and
00:40:22
controversy research teams in the United
00:40:25
States and Japan have developed a simple
00:40:27
and cost-effective method of
00:40:29
reprogramming human skin cells to
00:40:31
function much like embryonic stem cells
00:40:33
by introducing artificial
00:40:36
viruses while extracting and cloning
00:40:38
stem cells is complex and extremely
00:40:40
expensive the newly discovered method of
00:40:42
reprogramming cells is much cheaper
00:40:45
however the technique may disrupt the
00:40:47
DNA in the new stem cells resulting in
00:40:50
damaged and cancerous tissue more
00:40:53
research will be required before
00:40:55
non-cancerous stem cells can be created
00:41:06
the planned treatment trials will focus
00:41:08
on the effects of oral lithium on
00:41:10
neurological function in people with
00:41:12
chronic spinal cord injury and those who
00:41:14
have received umbilical cord blood
00:41:16
mononuclear cell transplants to the
00:41:18
spinal cord the interest in these two
00:41:21
treatments derives from recent reports
00:41:23
indicating that umbilical cord blood
00:41:25
stem cells may be beneficial for spinal
00:41:28
cord injury and that lithium May promote
00:41:30
regeneration and recovery of function
00:41:32
after spinal cord injury both lithium
00:41:35
and umbilical cord blood are widely
00:41:37
available therapies that have long been
00:41:39
used to treat diseases in humans
00:41:42
embryonic stem cells have the potential
00:41:44
to grow indefinitely in a laboratory
00:41:46
environment and can differentiate into
00:41:48
almost all types of bodily tissue this
00:41:51
makes embryonic stem cells a prospect
00:41:54
for cellular therapies to treat a wide
00:41:56
range of diseases
00:41:59
prolife supporters often claim that the
00:42:01
use of adult stem cells from sources
00:42:03
such as the umbilical cord blood has
00:42:05
consistently produced more promising
00:42:07
results than the use of embryonic stem
00:42:09
cells furthermore adult stem cell
00:42:12
research may be able to make great
00:42:14
advances if less money and resources
00:42:16
were channeled into embryonic stem cell
00:42:19
research stem cell research is highly
00:42:21
frowned upon in many ethical and
00:42:23
religious
00:42:24
groups in the past it's been an
00:42:27
necessity to research embryonic stem
00:42:29
cells and in doing so destroy them for
00:42:31
research to progress as a result of the
00:42:34
research done with both embryonic and
00:42:37
adult stem cells new techniques may make
00:42:39
the necessity for embryonic cell
00:42:41
research
00:42:43
obsolete because many of the
00:42:44
restrictions placed on stem cell
00:42:46
research have been based on moral
00:42:48
dilemas surrounding the use of embryonic
00:42:50
cells there will likely be rapid
00:42:52
advancement in the field as the
00:42:54
techniques that created those issues are
00:42:56
becoming less of a
00:42:58
necessity many funding and research
00:43:01
restrictions on embryonic cell research
00:43:03
will not impact research on ipscs
00:43:06
allowing for a promising portion of the
00:43:07
field of research to continue relatively
00:43:10
unhindered by the ethical issues of
00:43:12
embryonic
00:43:14
research adult stem cells have provided
00:43:16
many different therapies for illnesses
00:43:18
such as Parkinson's disease leukemia
00:43:21
multiple sclerosis lupus sickle cell
00:43:24
anemia and heart damage to date
00:43:27
embryonic stem cells have also been used
00:43:29
in treatment moreover there have been
00:43:32
many advances in adult stem cell
00:43:34
research including a recent study where
00:43:36
ppant adult stem cells were manufactured
00:43:39
from differentiated fibroblast by the
00:43:41
addition of specific transcription
00:43:44
factors newly created stem cells were
00:43:47
developed into an embryo and were
00:43:48
integrated into newborn Mouse tissues
00:43:51
analogous to the properties of embryonic
00:43:53
stem
00:43:54
cells research is underway to develop
00:43:57
various sources for stem cells and to
00:43:59
apply stem cell treatments for
00:44:01
neurodegenerative diseases and
00:44:03
conditions diabetes heart disease and
00:44:06
other conditions research is also
00:44:08
underway in generating organoids using
00:44:11
stem cells which would allow for further
00:44:13
understanding of human development
00:44:15
organogenesis and modeling of human
00:44:19
diseases in more recent years with the
00:44:21
ability of scientists to isolate and
00:44:23
culture embryonic stem cells and with
00:44:26
Scientists growing ability to create
00:44:28
stem cells using somatic cell nuclear
00:44:30
transfer and techniques to create
00:44:32
induced plottin stem cells controversy
00:44:35
has crept in both related to abortion
00:44:38
politics and to human
00:44:40
cloning hepatoxicity and drug induced
00:44:43
liver injury account for a substantial
00:44:45
number of failures of new drugs in
00:44:47
development and Market withdrawal
00:44:49
highlighting the need for screening
00:44:51
assays such as stem cell derived hepy
00:44:54
like cells that are capable of detecting
00:44:56
toxicity early in the drug development
00:44:59
process so where will this research take
00:45:02
us it may be at times an alarming
00:45:05
Prospect but even the toughest of
00:45:07
well-traveled Roads started with the
00:45:09
first few frightening steps steps that
00:45:12
were necessary in order to get to a
00:45:14
wonderful and at times better place that
00:45:18
is the true magic of science
00:45:21
[Music]
