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The gene is recessive, so if you received a copy of the gene from just one parent, you are a carrier of the sickle cell gene. Under certain conditions, after hemoglobin S releases its oxygen, its molecules clump together forming rigid and elongated crystals. The crystals settle to one side of the cell, which collapses the other side. These red blood cells, which normally look like miniature inner tubes, become stiff and distorted in appearance. Some cells take on the shape of a crescent or farmer's sickle, while others may resemble teardrops or stars. These misshapen cells stick to each other, and because of a chemical on their surface, they also stick the vessel walls. In the capillaries, the sticky, rigid, odd-shaped cells create a logjam. This causes a block in blood flow and deprives body tissues of their necessary oxygen. Without oxygen, cells begin to die and tissues suffer damage. These episodes are painful for the patient, but they are not permanent. Sickled red cells eventually regain their normal round shape when they are re-oxygenated and re-hydrated. Sickling can be triggered whenever the rate of blood flow is reduced, or when the body's supply of water or oxygen decreased. Some causes of sickling are dehydration, cold temperatures, a change in available oxygen or air pressure, and fever or a viral infection. Symptoms of the sickle cell anemia appear at about six months of age. Symptoms may be enlargement of the abdomen and heart, painful swelling of the hands and feet, anemia, aplastic crisis, acute chest syndrome, infections, splenic sequestration crisis, stroke, slow growth, and leg ulcers. In adolescence, sexual maturation may be delayed. The disturbances in blood flow associated with the disease also dispose affected persons to infections and leg ulcers. These symptoms are due to the change in hemoglobin, which changes shape when the amount of oxygen in the blood is reduced for any reason. The red blood cell in which the hemoglobin is contained changes its shape as well, from round to crescent (sickle shaped). The sickle-shaped red cells interfere with normal blood flow by plugging up small blood vessels. Early detection of sickle cell anemia can save lives. Newborn screening can be done before babies leave the hospital. Infants who are found to have sickle cell disease can be immediately entered into a program of pediatric care. Treatment for older patients are to take a daily multivitamin, decrease or avoid stress, Eat a well-balanced, highly nutritious diet, take all medications exactly as prescribed, drink plenty of fluids each day, get yearly eye exams from an ophthalmologist, and to learn all you can about sickle cell disease. The first effective drug treatment for adults with severe sickle cell anemia was reported in 1995. A study conducted by the NHLBI showed that daily doses of the anticancer drug, hydroxyurea, reduced the rate of painful crises. The study also found that those taking the drug needed fewer blood transfusions. Blood transfusions can correct anemia by boosting the number of normal red blood cells in circulation. In children, regular transfusions also can help prevent recurring strokes, other disabling nervous system complications and enlargement of the spleen before they become life threatening. A special blood test, called haemoglobin electrophoresis, can tell you whether you have a sickle cell disorder or are a healthy carrier. Researchers also are working on replacing the gene that makes defective hemoglobin in sickle cell disease patients with one that makes normal hemoglobin. In a laboratory experiment using blood cells from people who carry the sickle cell gene, researchers were able to change sickled cells into normal cells using an enzyme called a ribozyme. The ribozyme cut out the mutated instructions in the cells' genetic pattern and replaced them with the correct instructions, according to a report in the June 5, 1998, issue of Science. Next, researchers plan to try the technique on animals. There is no cure for sickle cell anemia yet, but in the coming years there should be something that will prevent people from getting it. People with sickle cell can live a mainly normal life. Most people join various support groups and should be under medical treatment. Bibliography: Word Count: 761
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