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Dna Electropherises Essay Research Paper DNA electrophoreses

Dna Electropherises Essay, Research Paper

DNA electrophoreses is a process in which a DNA strand is cut by a restriction enzyme at a certain point so it can be measured and compared with other DNA. The purpose of the lab was to determine the father of a child by comparing the child s DNA with that of the mother and two possible fathers. The child s DNA fits a combination of the real father and mother.

Electrophoresis begins with the pouring of the gel. The gel is an auger poured into a water bath. Combs are then placed in the forming gel to produce wells where the samples are then placed. The gel is placed in the electrophoresis apparatus and loaded with the samples. The different samples are loaded into the wells formed in the gel. The DNA samples are loaded using a measuring instrument called a micropipeter. There is then an electric current passed through the gel to separate the DNA fragments. The current separates the DNA segments by moving the smaller ones farther than the large ones. Every DNA sample separates differently. This way they can be compared with others. It is highly unlikely that two samples will have the same results.

Leukemia

Leukemia strikes all ages and both sexes. In 1995 approximately 20,400 people died from Leukemia. The all time five year survival rate is 38%. This rate has gone to 52% in the mid 1980 s. Approximately 25,700 cases were reported in 1995 alone(American Cancer Society-leukemia, 1995).

Leukemia is a form of cancer in the blood cells. Most forms of Leukemia occur in the white blood cells. These abnormal cells reproduce in large quantities and look and perform differently than normal cells(MedicineNet-leukemia, 1997).

Right now the causes of Leukemia are unknown. Some studies have shown that exposure to high-energy radiation increases chances of contracting leukemia. Such radiation was produced in the atomic bombing of Japan during World War II. There is also enough energy in nuclear plants so strict safety precautions are taken. Some research shows that exposure to electric magnetic fields, such as power lines and electric appliances, is a possible risk factor. More studies are needed to prove this link. Some genetic conditions, such as Down s syndrome, are also believed to increase the risk factor. Exposure to some chemicals is also suspected to be a risk factor. By learning the causes of leukemia treatment options will become available(MedicineNet-leukemia, 1997).

There are many symptoms of leukemia. The symptoms of leukemia are the same for all the different types of leukemia. The acute types of leukemia, ALL and AML, symptoms are seen more quickly than in the chronic types of leukemia, CLL and CML, where symptoms do not necessarily appear right away. The symptoms are flu symptom, weakness, fatigue, constant infections, easily bleed and bruise, loss of weight and appetite, swollen lymph nodes, liver or spleen, paleness, bone or joint pain, excess sweating, swollen or bleeding gums, nosebleeds and other hemorrhages, and red spots called petechiae located underneath the skin. In acute Leukemia the cancerous cells may collect around the central nervous system. The results can include headaches, vomiting, confusion, loss of muscle control, or seizures. These clumps of cancer cells can collect in other various parts of the body(MedicineNet-leukemia, 1997 and American Cancer Society-leukemia, 1995).

Leukemia can be diagnosed in a number of ways. Blood work is commonly done in the laboratory. Different forms of blood work include checking the hemoglobin count, platelet count, or white blood cell count. X-rays are routinely done for treatment follow-up. Ultrasound is also used as a treatment follow-up. CT Scan is a special type of x-ray used as a detailed cross section of a specific area of the body. Bone marrow is routinely tested to examine progress of the disease. Spinal taps are also used in certain types of cancers. The spinal fluid is checked to see if cancer cells are present(Parent and Patient handbook-hematology/oncology clinic, Children s Hospital of Michigan, 19??)

Treatment of Leukemia is very complex. Treatments are tailored to fit each patient s needs. The treatment depends on the type of the cancer and features of the cells. It also depends on the patient s age, symptoms, and general health. Acute Leukemia must be treated immediately. The goal of treatment is to get the cancer into remission. Many people with Leukemia may be cured. To be considered cured, you must be cancer free for at least five years. This time also varies depending on the type of cancer. The most common treatment of Leukemia is chemotherapy. Bone marrow transplants, Radiation, or biological therapy are also available options. Surgery is also occasionally used. Chemotherapy is a treatment method in which drugs are given to kill off the cancerous cells. One or more drugs may be used depending on the type of Leukemia. Anticancer drugs are usually given by IV injection. Occasionally they are given orally. Chemotherapy is given in cycles: a treatment period followed by a recovery period followed by another treatment period and this process continues for a certain amount of time. Radiation therapy is used along with chemotherapy in some occasions. Radiation uses high energy beams to kill the cancerous cells. Radiation can be applied to either one area or to the whole body. It is applied to the whole body before bone marrow transplants. Bone marrow transplants are used in certain patients. The patients bone marrow is killed by high doses of drugs and radiation. The bone marrow is then replaced by a donor’s marrow or the patient’s marrow that was remove before the high amounts of drugs and radiation. Biological therapy involves substances that affect the immune system s response to the cancer(MedicineNet-leukemia, 1997).

In conclusion, Leukemia can be fatal, but with early diagnosis, proper treatments, and a lot of luck, it can be put into remission. With treatment options improving constantly, there may one day be a sure cure. Leukemia is a very dominant disease and very hard to treat. The key may be in the causes.




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