Cystic Fibrosis Essays -- essays research papers

Cystic Fibrosis is a disorder where the exocrine glands secrete abnormally thick mucus, leading to obstruction of the pancreas and chronic infections of the lungs, which usually cause death in childhood or early adulthood. Some mildly affected patients may survive longer. Doctors can diagnose the disease by testing the patients perspiration because people with Cystic Fibrosis have high amounts of salt in their perspiration. Those with respiratory infections are treated with antibiotics, with aerosols that relieve constriction of the airways and liquefy the thick mucus, and by physical therapy to help patients cough up the obstructing secretions. Patients with pancreatic insufficiency can take pancreatic enzymes with meals. Intestinal obstruction, which occurs primarily in infancy (meconium ileus), may require surgery. The liver may also be seriously affected by Cystic Fibrosis. No cure for the disease has yet been found. Cystic fibrosis is the most common inherited fatal disease of Caucasians, occurring about once in every 2500 births. If both parents carry the gene responsible for the disease, they have a one-in-four chance of having an affected child. In 1989, the gene responsible for cystic fibrosis was identified on chromosome 7 (out of 23 chromosomes). Since that time more than 200 different mutations in the cystic fibrosis gene have been described, and tests have been developed to detect the most common alterations. These tests can identify unaffected carriers of the disorder. Sickle-Cell Anemia Sickle-Cell Anemia, also called sickle-cell disease, is a hereditary condition where hemoglobin, an oxygen-carrying protein in the blood, is altered, leading to periodic interruptions in blood circulation. All over the world. the disease is found predominantly in blacks, of whom approximately 1 in 400 are affected; it mainly occurs in the US, in the Middle East and the Mediterranean area. Symptoms of the condition appear at about six months of age and may include enlargement of the abdomen and heart and painful swelling of the hands and feet. 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 altered hemoglobin, which changes shape when the amount of oxygen in the b... ...vum having 24 chromosomes by a sperm with a normal assortment of 23, but they have also found that the sperm can carry the extra chromosome as well. The abnormal ovum or sperm is derived from a germ cell in which the pair of 21st chromosomes holds together and passes into the same sperm or ovum instead of separating. In the type of Down syndrome called translocation, the extra chromosome 21 material is attached to one of the other chromosomes; when some, but not all, of the body's cells carry an extra chromosome 21, the condition is a type of Down syndrome called mosaicism. Down syndrome is not yet responsive to medical treatment, but better medical care of the accompanying disorders and infections now results in an almost normal life span instead of the previous life expectancy of about 14 years. The severely retarded may still be institutionalized, but many Down syndrome children are raised at home, where their full potential can be developed. Although, with an average mental age of about eight years, they continue to need a protective environment, many adults with Down syndrome work in sheltered workshops; some hold regular jobs in business and industry.