under study is the addition of chemicals or growth factors that aim to induce the patient’s own stem cells to repair the damaged nerves without needing to grow and transplant stem cells.Possible Fix for Diabetes? In people who suffer from type I diabetes, the beta cells of the pancreas that normally produce insulin are destroyed by the patient’s overactive immune system. Without insulin, the cells of the body cannot take up glucose and they starve. Patients with type I diabetes16WHY STEM CELL RESEARCH IS BEING PURSUEDS T E M C E L L T I M E L I N EWHY STEM CELL RESEARCH IS BEING PURSUEDrequire insulin injections several times a day for their entire lives. The only current cure is a pancreatic transplant from a recently deceased donor, but the demand for transplants far outweighs the supply. While adult stem cells have not yet been found in the pancreas, scientists have made progress transforming embryonic stem cells into insulin-producing cells. Combining beta-cell transplants with methods to “fix” the patient’s immune system—including chemotherapy to destroy malfunctioning immunesystem cells and blood transplants to replenish healthy white blood cells—could offer great hope for the many Americans suffering with type I diabetes. Cancer: Getting to the Root of the Problem Why are some cancers so hard to eliminate, even after many rounds of chemotherapy? The answer may lie ina few abnormal stem cells. Cancerous stem cells were first identified in 1997 when a research group from the University of Toronto transferred a few blood stem cells from human leukemia patients into mice and watched leukemia develop in the mice. Stem celllike cells have also recently been found in breast and brain tumors. Like normal stem cells, tumor stem cells exist in very low numbers, but they
can replicate and give rise to a multitude of cells. Unlike normal stem cells, however, cancerous stem cells lack the controls that tell them when to stop dividing. Traditional chemotherapy kills off the majority of the tumor cells, but if any of the cancerous stem cells survive the treatment, the cancer may return. Research into the differences in gene expression between normal and tumor stem cells may lead to treatments where the root of the problem—the cancer stem cell—is targeted. Stem cell research continues to advance.Preliminary results from recent studies support the promise of stem cells for conducting basic research that may eventually lead to medical achievements.For example,in 2005,human embryonic stem cells were shown to differentiate into active functioning nerve cells when placed in mouse brains.Scientists also made significant progess in deriving pancreatic cells from adult stem cells.In 2006,scientists were able to derive embryonic stem cells from the morula of a mouse,and embryonic stem cells were first grown without animal products in the culture. Results of these and other recent experiments must be replicated and consistently demonstrated by other researchers before they become generally accepted by the scientific community.
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- Spring '17
- Carl bradshaw
- identity of the powerful cells, existence of stem cells