Friday, December 31, 2010

Steam Cells Cure Blindness (Word count: 445)








Steam Cells Cure Blindness (Word count: 445)

What are Stem Cells:


Stem Cells are basic cells found in all multi cellular organisms, like humans and plants. These cells are characterized with the ability to perform mitotic cell division(mitosis).There are two types of stem cells known that can be obtained from mammalian creatures, embryonic stem cells and adult stem cells.  In adult organisms, stem cells and progenitor cells act as a repair system for the body, replenishing specialized cells, but also maintain the normal turnover of regenerative organs, such as blood, skin, or intestinal tissues. By far the most important property stem cells have, is their ability to be incorporated in any part of the body, they can be used in repairing the cornea, the heart, liver, etc.

 

Extracting Stem Cells
 


Social Impact of Stem Cells:
 

On August 9, 2001, President George W. Bush announced his decision to allow Federal funding of research only on existing human embryonic stem cell lines created prior to his announcement. His concern was to not foster the continued destruction of living human embryos. In 2004, both houses of Congress have asked President George W. Bush to review his policy on embryonic stem cell research. President George W. Bush released a statement reiterating his moral qualms about creating human embryos to destroy them, and refused to reverse the federal policy banning government funding of embryonic stem cell research. In the November 2004 election, California had a Stem Cell Research Funding authorization initiative on the ballot that won by a 60% to 40% margin. It established the "California Institute for Regenerative Medicine" to regulate stem cell research and research facilities. It authorizes issuance of general obligation bonds to finance institute activities up to $3 billion dollars subject to an annual limit of $350 million. 

Stem Cell Treatments: 


The loss or degeneration of photoreceptors in the retina, the light sensing receptors in the eye, leads to blindness. This is the mechanism seen with age-related macular degeneration, a common age-related disease. Several approaches to replacing the photoreceptors have been attempted, but a recent study in the journal Cell Stem Cell indicates that embryonic stem cells may hold the key. In 2004, Klassen et al. looked at retinal progenitor cells isolated from day-old mice and found some improvement in light-mediated behavior of adults with retinal grafts, indicating that the neurons regenerated the retina to some extent. That same year, Coles et al. looked at retinal stem cells and found that they could differentiate into retinal cells. Two years later, MacLaren et al. showed that these stem cell-derived cells could be transplanted and populate a damaged eye. Also in 2006, Lamba et al. showed that embryonic stem cells could be directed to become retinal cells, including photoreceptors expressing specific markers, something the other cell types had not achieved.




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