In Biology, the term of original cells indicates undifferentiated cells which, on the one hand, can give specialized cells (differentiation) and, on the other hand, can be virtually renewed indefinitely.
They would be for example partly responsible for the regeneration of the members in certain animals. This phenomenon is very widespread among the Métazoaire S but it appears also at certain Vertébrés (like the Lézard or the Salamandre). Experiments carried out on the Rat S show that these cells are able to be different in a given type of cell and thus to restore bodies. It is the cellular Thérapie.
The original cells are present at the stage Embryon naire, and in the adult organization. However they are much rarer in the adult organization. Being given the advantages which they have, the therapeutic Clonage thus appeared in order to manufacture some.
However, in the animals, each fabric what is called has original cells, these original cells are less pluripotentes that the embryonic original cells i.e. that while being different they cannot, in general to give another type of fabrics that which they must regenerate (see animal Original cell). They can be different as a whole from the cells which constitutes the fabric given, for example when one speaks about the blood tissue which contains the Blood cells, one generally speaks about the hematopoietic (CSH) original cell which alone make it possible to recreate all the blood cells, however the original cells of a fabric are contained in this fabric.
Biology
See also: animal Original cell, Méristème
In a general way, the original cells are present at all the living beings Pluricellulaire S. They indeed play a very important part in the development of the organizations like in their maintenance.
Role of the original cells
One can wonder why create or regenerate cells in a fabric, there are several reasons with that:
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the body containing fabric must grow either during the growth, or to be able to provide a function, for example the Cœur of the athletes is larger, the Utérus grows bigger during the Grossesse, etc
- the cells age (for example the red Globules) and those must be renewed.
- a Traumatism, a Ischaemia, or other phenomena can create the death of cells which must be regenerated, unfortunately this regeneration is sometimes not sufficiently effective either because there are not enough original cells, or because the Architecture of fabric is upset too much (that depends much on fabric and the attack of this one).
Medicine
See also: Original cell (medicine)
In Medicine, the human animal original cells and in particular original cells are the subject of many research currently, in particular in order to regenerate fabrics to even create of any part of fabrics and Organe S. the origin of the cells poses also problems of ethical, because of the independent source of original cells: the embryo. Fortunately of new sources (much more practical) of original cells were discovered, like the cells of the blood of umbilical cord, or the original cells in fat fabric (even a thin person can provide one liter of grease!).
In a near future, the original cells could be used to look after cerebral diseases such as the Maladie of Alzheimer.
However, these original cells was recently implied in origins of Cancer S. Indeed, the original cells would be the only ones to have the possibility of transferring sufficiently to become cancer cells, because of the time necessary to these changes - several years - whereas the differentiated cells only have an life expectancy of a few weeks), and are also responsible for the repetitions of cancers. These studies thus throw a shade on these so much praised cells.
See too
http://www.radio-canada.ca/nouvelles/Science-Sante/2007/01/08/002-cellules-liquieamniotique.shtml
Related articles
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