LEARN ABOUT ORIGINAL CELL (Part 3)

Author: Dr. Tran Manh Hung , MA, STD
Original English

II. ORIGINAL STUDY

1. Where does stem cells come from?

We all start life from a single cell, called zygote, that forms after fertilization. Zygote divides into two cells; every cell in it divides and goes on like that. Soon, about 5 days after fertilization, the zygote takes the form of an empty balloon, with about 150 cells called blastocysts. The embryo is even smaller than a grain of sand, consisting of two cell groups: trophoblast and intracellular cells in the blastocyst. Embryonic stem cells are cells that form inner cell mass. Because embryonic stem cells can form any type of cell in the adult body, it is also considered a pluripotent stem cell.

Stem cells can also be found in certain types of human tissue that have been fully developed, from children to adults, in very small numbers. For example, bone marrow stem cells (blood stem cells) are found in the bone marrow, they develop into all types of specialized blood cells.

1. Fertilization: Fertilization
2. 8-Cell embryo: Embryos consist of 8 cells. In this stage of development, embryonic stem cells are considered to be totipotent stem cells; Each of these cells has the potential to grow into a human being.
3. Blastocyst: Embryo. During this stage of development, embryonic stem cells are considered pluripotent stem cells; Each of these cells has the potential to develop into any cell in the body.
4. Fetus: Fetus . During this stage of development, embryonic stem cells are considered pluripotent stem cells; Each of these cells has the potential to develop into any cell in the body.
5. Stem cells are also found in adult bodies. They maintain and cure the body. They are located in many cells in the body. Adult stem cells have the potential to receive specific properties, in order to form cells of limited numbers in tissues. They are considered as pluripotent stem cells (Multipotent stem cells).

CARE OF CHRISTMAS ORIGINAL CELL

Liver: Gan
Brain: Brain
CNS stem cells: CNS stem cells
Skeletal muscle: Musculoskeletal
Bone: Bone
Blood cell: Blood cell
Blood vessel: Blood vessel
Bone marrow stromal cell: bone marrow cells
Epithelial cell: Epithelial cells
Neuron: Neutron
Glial cell: Glial cell
Fat cell: Fat tissue cells
Cardiac muscle: Heart muscle

Adult stem cells are programmed specifically to form different cell types for their tissues. These cells are called multipotent stem cells. Scientists have not yet identified all adult stem cells in vital organs of the body. Some tissues like the brain, although stem cells exist, do not work, so they are not ready to react to damaged or injured cells. Currently scientists are also looking for ways to stimulate existing stem cells so that they develop and create the right type of cells to replace damaged cells.

ORIGINAL CELLS CAN BE HARVESTED FROM SOURCES AS FOUNDING, PREGNANT OF BIRTHDAY

Fig.1 The Umbilical Cord: Umbilical cord

Fig.2 The Amniotic Fluid: Amniotic fluid

Figures 1 and 2: Stem cells can also be harvested from newborn sources such as umbilical cord, amniotic fluid or placenta.

This is an accessible source of stem cells, compared with mature brain or bone marrow tissue. Although scientists can create these cells on culture plates, they are very limited. Recently, scientists have discovered the existence of stem cells in children's milk teeth and amniotic fluid surrounding the fetus. These cells may also have the potential to form many other cell types. The study looked at the characteristics of these cells very promising, but only in the early stages.

2. Types of stem cells

Each of us contains stem cells, from the first stages of development to the end of life.

There are basically 3 types of stem cells: total stem cells, almighty stem cells and pluripotent stem cells.

TYPES OF ORIGINAL CELLS

Stem cell type

Describe

For example

Total stem cells

Each cell can grow into a new individual

Embryonic cells at a new stage of development (from 1 to 3 days)

Almighty stem cells

Cells can form any type of cell in the body (over 200 types)

Embryonic stem cells are found in blastocysts (from 5 to 14 days).

Versatile stem cells

Cells have been differentiated, but can still form some other cell types

Fetal tissue, umbilical cord blood and adult stem cells

All stem cells are useful in medical research, but each has its own potential and limitations. Embryonic stem cells are formed very early in human development, such as blastocysts, with the potential to produce all types of body cells. Adult stem cells are only found in certain types of tissues in humans that have been fully developed, from children to adults, only limited to certain specific types of cells.

DIFFERENT SOURCES OF ORIGINAL CELLS

Embryonic stem cells: Embryonic stem cells
Early human embryo at blastocyst stage: Embryos in the blastocyst stage
Adult stem cells: Adult stem cells
From bone marrow in this example: Retrieved from bone marrow
Totipotent cells: Total stem cells
Pluripotent cells: Almighty stem cells
Cultured stem cells: Stem cells are cultured
Different culture conditions: Different culture conditions
Differe nt types of differentiated cells: Different types of differentiated cells
Liver cells: Liver cells
Nerve cells: Nerve cells
Blood cells: Blood cells

3. What is embryonic stem cells?

Embryonic stem cells can be produced from in vitro fertilization (IVF). Embryonic stem cells originate in cells that make up the intracellular mass in the blastocyst. Mouse embryonic stem cells are capable of producing any type of cell in the body under appropriate conditions. Therefore, embryonic stem cells are considered omnipotent cells, capable of indefinitely dividing until growth and differentiation. Stem cells divide successively in the tissue culture environment in the incubator, but at the same time maintain the ability to form other types of cells when placed in a suitable environment to promote differentiation.

Stem Cells From In Vitro Fertilization (IVF): Stem cells are derived from in vitro fertilization
Unused, frozen embryo slated to be thrown away: Unused and frozen embryos are fired
Pluripotent stem cells: Almighty stem cells
Pancreactic (islet cells): pancreatic cells
Hematopoietic (blood cells): blood cells
Cardiomyocytes (heart cells): heart cells
Neurons (brain cells): Neron
Hepatocytes (liver cells): liver cells

Human embryonic stem cell samples are currently being studied. Several research groups are investigating whether human embryonic stem cells possess the same characteristics as mouse embryonic stem cells. Because human embryonic stem cells have only recently been isolated, our understanding is limited in the way that stem cells are divided. Conducting research on the human body system is also more difficult than mice. However, researchers have been making significant progress, in order to find therapies to replace or restore damaged tissues, in the use of these stem cells.

How cloning can be used therapeutically:
How are cloning techniques applied in treating diseases?
Anucleate unfertilized egg from donor:
Unfertilized donor eggs are separated
Nucleus Transfer: Cell transfer
Adult cell from patient: Mature cells of patients

Human embryonic stem cells can also be harvested through nuclear transfer. Cell nuclear transfer technology, an example of skin cells is also a potential way to produce embryonic stem cells.

In animals, the transfer technique is performed by multiplication of differentiated adult cells, eg skin cells, for example, into separated eggs. The egg contains the genetic material of skin cells, which is then stimulated to form the blastocyst, which can then be harvested. The stem cells created in this way are clones or clones of the original adult cells due to the ^fourth DNA in their nuclei similar to the adult cell's DNA.

Until the summer of 2006, transfer technology was not successful, to create human embryonic stem cells, but advances in animal research give us hope that scientists can use technology. This transformation in creating human stem cells in the future.

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Note:

⁴ . DNA stands for "Deoxyribonucleic Acid". Genetic material found in all living things; contains the inherited characteristics of every living organism - genetic basic constitution.

Tra Mi translates
Complete translation of Tran Manh Hung
Copyright © 2008 byTrần Mạnh Hùng

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