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Stem cells. We need to live longer and to be developed healthier . Stem cells are thought to hold huge potential for treating a wide range of disease and disability. Scientists around the world are working on techniques to refine stem cell therapy. BBC.
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Stem cells are thought to hold huge potential for treating a wide range of disease and disability. • Scientists around the world are working on techniques to refine stem cell therapy. BBC
Now a days the term is adopted to the concept of functional repair of tissues..............
Background • 1908 - the term was proposed for scientific use by the Russian histologist Alexander Maksimov (1874–1928) at congress of hematologic society in Berlin. It postulated existence of haematopoietic stem cells that are precursors of blood cells............................
Sources of stem cells • All multicellular organisms from the first division till aged..............................................
characteristics • Self renewal. • Potency .
Functional classification • Totipotent • Pluripotent • Multipotent • Oligopotent • Unipotent
Resources • First division/s • Embryo • Amniotic fluid • Umbilical cord blood • Adult tissues and bone marrow • Futuristically normal cells reverse
In a developing embryo, stem cells derived from the early cell divisions can differentiate into all of the specialized embryonic tissues and approaching term the degree of yielding various tissues recedes.
Considering the highly plastic adult stem cells from a variety of sources, including umbilical cord blood and bone marrow, are routinely used in medical therapies. Apart of the presence of more differentiated cells i.e. those of limited diversity. • NB: foetal stem cells are grouped within adult stem cells although distinction appears necessarily. ( can I aid my pears?..... remember I can not decide )
Multipotent stem cells are also found in amniotic fluid. These stem cells are very active, expand extensively without feeders and are not tumorogenic. Amniotic stem cells are multipotent and can differentiate in cells of adipogenic, osteogenic, myogenic, endothelial, hepatic and also neuronal lines.
Embryonic derived stem cells are a much of a debate for ethical and religious......... • Reverse • ? Finding a species on earth or universe .....
Diagram of stem cell division and differentiation. A - stem cell; B - progenitor cell; C - differentiated cell; 1 - symmetric stem cell division; 2 - asymmetric stem cell division; 3 - progenitor division; 4 - terminal differentiation
Technical issue • Clonogenic testing • Are they? • Induction • Reverse
Totipotent stem cells can differentiate into embryonic and extraembryonic cell types. Such cells can construct a complete, viable, organism. These cells are produced from the fusion of an egg and sperm cell.
Pluripotentstem cells are the descendants of totipotent cells and can differentiate into nearly all cells i.e. cells derived from any of the three germ layers