Stem cells are perhaps the most surprising discoveries of science. Stem cell therapy – is a breakthrough of the century in medicine that can change the perception of the treatment of many diseases and give people the most important – health, youth, strength, and longevity.
A stem cell is a cell that has the ability to self-renew through mitotic divisions or continue the differentiation pathway which is scheduled and, therefore, produce one or more cells in mature tissues, functional and fully differentiated according their degree of multipotency. Stem cells are the hierarchy of the special cells of living organisms, each of which can subsequently change in a special way. Stem cells can divide asymmetrically, because they are formed by dividing cells, similar to the parent (self-reproduction), as well as a new cell that can differentiate. Stem cells in our body are very small: embryo has 1 cell per 10,000, and a person of 60-80 years – 1 cell by 5-8 million.
The sources of stem cells are: embryonic, cord and adult cells.
Embryonic stem cells (ESCs) are derived from the so-called inner cell mass of early embryos to the blastocyst stage (4-7 days of development). This “ideal” stem cells are those from which further develops the whole body. All the specialized cells of the body, as the formation of the embryo, are differentiated from unspecialized embryonic stem cells.
Stem cells from umbilical cord blood have specific characteristics that allow them to be stored for a long time, and they are used to replace various types of cells. In addition, their removal is painless, safe, and not inconsistent with ethical considerations.
Adult stem cells of the body. During the life of an adult organism is constantly facing the death of cells of various tissues, as in the natural regeneration (apoptosis), and when there is damage (necrosis). Recovery of lost cells is due to cambial elements. In the intestines, skin, muscle, bone marrow, liver, brain, there is tissue-specific proliferating cell population.
The term “stem cell” was introduced into scientific use Russian histologist Alexander Maximov (1874-1928). In the sixties of the XX century Teal and Makkuloh and Metcalfe and his colleagues showed that intravenous administration of bone marrow cells from healthy syngeneic to lethally irradiated mice leads to the formation of colonies of cells of all lines of hematopoietic differentiation in the spleen.
The potential use of stem cells. According to scientists, the use of own or alien stem cells can be effective in diseases such as leukemia, various anemia, certain tumors, cancer of the lymph glands. In the future, doctors hope to find a use to these cells for the treatment of autoimmune disorders, including multiple sclerosis, diabetes, as well as tissue damage, for example, as a result of a heart attack, brain injury in early childhood, chronic inflammatory tumors, because of the bone diseases, and skin transplants. Experts see many perspectives in the usage of the stem cells. For example, the stem cells were found in umbilical cord blood to treat patients with cancer. This means that there will be considerable benefits for the humanity in the usage of the stem cells.
Controversy and stem cell research with embryonic cells. The ethical dimension is the main source of embryonic stem cells when the abortive material or material that remains unused after in vitro fertilization. But many religious and moral people believe that such use of the human embryo is unacceptable. Firstly, if God gave him life, then he gave both the soul, and using it – is a murder. And secondly, it is unethical to use a single living creature that can not express their will for the salvation of another living being.
Stem cell research is controversial because there are ethical issues that may disturb people. The meaning of the stem cell treatment is that the full potential for healthy and continuity life in our bodies laid at the outset. Our body has special cells that continually bring us back to normal – they are the stem cells. As we age, stem cells are not so active, so it makes sense to use them, and in addition, to preserve youth and health.
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