Unaweza kuotesha sikio lililokatika ?(stem cell)

KAKA A TAIFA

JF-Expert Member
Apr 27, 2011
566
80
[h=1]First, what are stem cells, and where are they found?
Stem cells are the basic seed cells of the body. In the same way that seeds turn into flowers, stem cells turn into the mature cells that perform the functions of all the organs and tissues in the body. [h=3]What is the difference between adult stem cells and embryonic stem cells?[/h]
Stem cells derived from early embryos are "totipotent," which means that they can become any cell type in the body. After all, people start out as a single fertilized egg. That single cell begins a process of cell division that results in all the different cells of the body. As the embryo grows into a fetus and then a baby, the potentiality, or the flexibility of those stem cells, diminishes. We're not certain yet whether adult stem cells, or cord blood cells, which are also rich in stem cells, will be flexible enough to repair brain cells, for example, or heart muscle cells. That's why there is major interest in embryonic stem cells. Stem cell transplantation has already proven successful in leukemia, where we use it to restore blood production after high-dose chemotherapy.
And as we continue to get a clearer understanding of stem cell biology, we are beginning to see how stem cells derived from marrow cells or blood cells or embryonic cells might be used to repair damaged hearts or brains. I think that's potentially very exciting. When it will happen is not certain. I think it could be between five and ten years away. But I might be too pessimistic there.
I do. I think that in terms of gene transfer, which is a process of inserting genetic material into the stem cells to try and treat genetic disease, we should be cautious. We should be cautious with hybridization experiments, and with cloning as well. Any time you transfer genes within the cloning process, or change the genetic material within a cell, there may be defects introduced into a natural organ or species development. I think I would be quite cautious there.
But in terms of differentiating embryonic stem cells and adult stem cells into different kinds of cells -- liver, heart, lung, brain -- I would be less cautious there. I think the potential for damage or danger is much more limited.
[h=4]Bone marrow transplant [/h]A bone marrow transplant delivers healthy bone marrow stem cells into the patient. It replaces bone marrow that is either not working properly or has been destroyed (ablated) by chemotherapy or radiation ..Images for What A Stem Cell Is































































































































[/h]
 
Back
Top Bottom