In vitro fertilization is a procedure that childless couples may use when they are having trouble conceiving the natural way. It is the next step after artificial insemination has failed to yield the desired result. The IVF procedure involves fertilization of the woman's eggs in a petri dish and then implanting the resulting embryos. Unused embryos are a byproduct of this process. There are a number of different ways of dealing with these and it is the responsibility of the parents to determine what happens to them.
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 undifferentiated cells at an early stage of development. They have the potential to differentiate into other types o f mature cell. This is referred to as pluripotency. Stem cells are becoming increasingly useful as a medical treatment for all sorts of conditions. Because this procedure is open to serious abuse, it is tightly regulated.
Scientists at a Utah university first injected stem cells into the hearts of patients as a therapeutic strategy for heart failure. Cells were derived from the patient's bone marrow and then cultured for just short of two weeks. Those that survived in tissue culture became stronger than the patient's original bone marrow. These cells were then placed into the left side 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 the spongy tissue located deep in the center of some of the larger bones in the body, mostly from the pelvic bone. Harvesting stem cells from this location is extremely painful so the donors are placed under a general anesthetic. A large needle is then placed into the marrow via the hip bone and the cells are harvested.
Under normal physiological conditions, peripheral blood does not contain vast numbers of stem cells. Loading the donors with hormonal growth factors leads to a notable increase in the numbers of these cells. Neonatal blood is teeming with stem cells. Those remaining in the umbilical cord are removed and stored at extremely low temperatures, as low as -200 Kelvin and reserved for transplantation at a later date or until the parents decide what to do with them.
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 undifferentiated cells at an early stage of development. They have the potential to differentiate into other types o f mature cell. This is referred to as pluripotency. Stem cells are becoming increasingly useful as a medical treatment for all sorts of conditions. Because this procedure is open to serious abuse, it is tightly regulated.
Scientists at a Utah university first injected stem cells into the hearts of patients as a therapeutic strategy for heart failure. Cells were derived from the patient's bone marrow and then cultured for just short of two weeks. Those that survived in tissue culture became stronger than the patient's original bone marrow. These cells were then placed into the left side 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 the spongy tissue located deep in the center of some of the larger bones in the body, mostly from the pelvic bone. Harvesting stem cells from this location is extremely painful so the donors are placed under a general anesthetic. A large needle is then placed into the marrow via the hip bone and the cells are harvested.
Under normal physiological conditions, peripheral blood does not contain vast numbers of stem cells. Loading the donors with hormonal growth factors leads to a notable increase in the numbers of these cells. Neonatal blood is teeming with stem cells. Those remaining in the umbilical cord are removed and stored at extremely low temperatures, as low as -200 Kelvin and reserved for transplantation at a later date or until the parents decide what to do with them.
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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