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Stem Cell Policy

Essay by   •  March 19, 2011  •  3,088 Words (13 Pages)  •  909 Views

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One cannot mention the word stem cells in a political forum with out it causing fervor of opinion and discussion. What is it about this new medical science that makes people have such divided views on the issue? I will be discussing this and more as I look at the issue of stem cells some opinions on stem cells and track two different bills on stem cell research and application

So what are stem cells and why are they important? Stem cells have two important characteristics that distinguish them from other types of cells. First, they are unspecialized cells that renew themselves for long periods through cell division. The second is that under certain physiologic or experimental conditions, they can be induced to become cells with special functions such as the beating cells of the heart muscle or the insulin-producing cells of the pancreas. (NIH 2005)

Scientists primarily work with two kinds of stem cells from animals and humans: embryonic stem cells and adult stem cells, which have different functions and characteristics that will be explained in this document. Scientists discovered ways to obtain or derive stem cells from early mouse embryos more than 20 years ago. Many years of detailed study of the biology of mouse stem cells led to the discovery, in 1998, of how to isolate stem cells from human embryos and grow the cells in the laboratory. These are called human embryonic stem cells. The embryos used in these studies were created for infertility purposes through in vitro fertilization procedures and when they were no longer needed for that purpose, they were donated for research with the informed consent of the donor. (NIH 2005)

Stem cells are important for living organisms for many reasons. In the 3- to 5-day-old embryo, called a blastocyst, stem cells in developing tissues give rise to the multiple specialized cell types that make up the heart, lung, skin, and other tissues. In some adult tissues, such as bone marrow, muscle, and brain, discrete populations of adult stem cells generate replacements for cells that are lost through normal wear and tear, injury, or disease. (NIH 2005)

It has been hypothesized by scientists that stem cells may, at some point in the future, become the basis for treating diseases such as Parkinson's disease, diabetes, and heart disease. (NIH 2005)

Scientists want to study stem cells in the laboratory so they can learn about their essential properties and what makes them different from specialized cell types. As scientists learn more about stem cells, it may become possible to use the cells not just in cell-based therapies, but also for screening new drugs and toxins and understanding birth defects. However, as mentioned above, human embryonic stem cells have only been studied since 1998. Therefore, in order to develop such treatments scientists are intensively studying the fundamental properties of stem cells, which include: (NIH 2005)

1. Determining precisely how stem cells remain unspecialized and self renewing for many years; and

2. Identifying the signals that cause stem cells to become specialized cells.

(NIH 2005)

What makes stem cells so amazing is that we are on the verge of a new medical techknology that has the potential not to treat disease but to cure it here is a just a short list of some of the diseases that stem cell applications could cure.

Blindness: Since 2003, researchers have successfully transplanted retinal stem cells into damaged eyes to restore vision. (Wikipedia 2006)

Missing teeth: In 2004, scientists at College King's discovered a way to cultivate a complete tooth in mice and were able to grow them stand-alone in the laboratory. (Wikipedia 2006)

Low blood supply: In December 2004, a team of researchers led by Dr. Luc Douay at the University of Paris developed a method to produce large numbers of red blood cells. The Nature Biotechnology paper, entitled Ex vivo generation of fully mature human red blood cells, describes the process: precursor red blood cells, called hematopoietic stem cells, are grown together with stromal cells, creating an environment that mimics the conditions of bone marrow, the natural site of red blood cell growth. (Wikipedia 2006)

Heart damage: Several types of heart disease have been treated in clinical trials and therapy is commercially available. Patients such as Jeannine Lewis[8] and legendary Hawaiian crooner Don Ho have traveled to Thailand to receive stem cell therapy for their heart disease. Using the patient's own bone marrow derived stem cells or more recently, peripheral blood-derived stem cells, Dr. Amit Patel at the University of Pittsburgh, McGowan Institute of Regenerative Medicine has shown a dramatic increase in ejection fraction for patients with congestive heart failure. (Wikipedia 2006)

Muscle damage: Adult stem cells are also apparently able to repair muscle damaged after heart attacks. Heart attacks are due to the coronary artery being blocked, starving tissue of oxygen and nutrients. Days after the attack is over, the cells try to remodel themselves in order to become able to pump harder. However, because of the decreased blood flow this attempt is futile and results in even more muscle cells weakening and dying. Researchers at Columbia-Presbyterian found that injecting bone-marrow stem cells, a form of adult stem cells, into mice which had had heart attacks induced resulted in an improvement of 33 percent in the functioning of the heart. The damaged tissue had regrown by 68 percent. (Wikipedia 2006)

Spinal cord injury: A team of Korean researchers reported on November 25, 2004, that they had transplanted multipotent adult stem cells from umbilical cord blood to a patient suffering from a spinal cord injury and she can now walk on her own, without difficulty. The patient had not even been able stand up for the last 19 years. The team was co-headed by researchers at Chosun University, Seoul National University and the Seoul Cord Blood Bank (SCB). For the unprecedented clinical test, the scientists isolated adult stem cells from umbilical cord blood and then injected them into the damaged part of the spinal cord. While exciting, many more studies are required to establish that such treatments are effective. (Wikipedia 2006)

Parkinsons disease multiple sclerosis Alzhimers : The Childrens Hospital and Harvard Medcial School in Boston, provides the first evidence from studies in animals that neureal stem cells can be used to repair damage from brain disorders such as multiple sclerosis , where cell dyfuntion is global throughout

the brain. While peliminary the new findings raise exciting possiblites for future therapies.

The issue of stem cell research burst

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