When couples have difficulty conceiving a child by any other means, including artificial insemination, they may decide to try in vitro fertilization. In this process, the woman's eggs may be fertilized in the laboratory; the resulting embryos are then implanted into her uterus. Unused embryos that do not get implanted remain the responsibility of the parents from whose cells they are derived.
After fertilization has taken place, the extra embryos are frozen and stored. Today's techniques for freezing this tissue enable these tissues to retain their viability for a matter of years. The parents can decide to leave them in storage, donate them for medical research, hand them over to other couples who are having difficulty conceiving by any other means, or they may keep storing them until they decide their fate or elect to have them sent for destruction.
Stem cells are very primitive cells that have the potential to differentiate into just about any other cell type in the human body. This property is referred to as pluripotency. These cells are becoming more and more useful in medicine. There is a significant potential for abuse of these cells. For this reason, their use is very closely regulated by governmental authorities.
Scientists at the University of Utah were the first to inject stem cells into the left ventricles of patients to treat heart failure. Cardiac repair cells were drawn from the patients' own bone marrow and placed into culture for around 12 days. The cells that survived in culture turned out to be stronger than the patient's original cells and were injected into the left ventricles of the patients' hearts.
The first time stem cells were isolated from mice was in 1981; in humans, it was 1998. These cells may arise from spare human embryos that did not need to be implanted. Other places where stem cells come from include peripheral blood, umbilical cords and bone marrow. Other conditions apart from heart failure where stem cells have been used include diabetes, neurological problems and cancer.
Bone marrow is located deep inside the large bones of the body; specifically, the pelvic bone. Getting to these cells is a highly painful procedure so it is commonly accomplished with the use of a general anesthetic. Then, a large-bore needle is used to draw the cells via the hip bone.
Typically, peripheral blood is not endowed with a plethora of stem cells. In this case, patients are prepared by giving them hormones called growth factors. This takes place a few days prior to harvesting. The actual collection process may take hours. Newborn blood is also rich in these cells. Some remain in the umbilical cord, which is set aside for future transplantation. To date, human umbilical cord cells have only been transplanted into small adults and children.
Once the parents are sure they do not want any more children, there are a number of things they can decide to do with the extra embryos. They may donate them for research, discard them or allow them to be passed on to other childless couples who are unable to conceive by other methods.
After fertilization has taken place, the extra embryos are frozen and stored. Today's techniques for freezing this tissue enable these tissues to retain their viability for a matter of years. The parents can decide to leave them in storage, donate them for medical research, hand them over to other couples who are having difficulty conceiving by any other means, or they may keep storing them until they decide their fate or elect to have them sent for destruction.
Stem cells are very primitive cells that have the potential to differentiate into just about any other cell type in the human body. This property is referred to as pluripotency. These cells are becoming more and more useful in medicine. There is a significant potential for abuse of these cells. For this reason, their use is very closely regulated by governmental authorities.
Scientists at the University of Utah were the first to inject stem cells into the left ventricles of patients to treat heart failure. Cardiac repair cells were drawn from the patients' own bone marrow and placed into culture for around 12 days. The cells that survived in culture turned out to be stronger than the patient's original cells and were injected into the left ventricles of the patients' hearts.
The first time stem cells were isolated from mice was in 1981; in humans, it was 1998. These cells may arise from spare human embryos that did not need to be implanted. Other places where stem cells come from include peripheral blood, umbilical cords and bone marrow. Other conditions apart from heart failure where stem cells have been used include diabetes, neurological problems and cancer.
Bone marrow is located deep inside the large bones of the body; specifically, the pelvic bone. Getting to these cells is a highly painful procedure so it is commonly accomplished with the use of a general anesthetic. Then, a large-bore needle is used to draw the cells via the hip bone.
Typically, peripheral blood is not endowed with a plethora of stem cells. In this case, patients are prepared by giving them hormones called growth factors. This takes place a few days prior to harvesting. The actual collection process may take hours. Newborn blood is also rich in these cells. Some remain in the umbilical cord, which is set aside for future transplantation. To date, human umbilical cord cells have only been transplanted into small adults and children.
Once the parents are sure they do not want any more children, there are a number of things they can decide to do with the extra embryos. They may donate them for research, discard them or allow them to be passed on to other childless couples who are unable to conceive by other methods.
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