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Is high ANA titer an indication of disease progression in rheumatoid arthritis?
The acronym ANA stands for anti-nuclear antibody. When your doctor suspects you may have an autoimmune disorder, he or she will test for the presence of anti-nuclear antibodies in your blood. To perform the ANA test, serum from your blood specimen is added to microscope slides which have commercially prepared cells on the slide surface. If your serum contains antinuclear antibodies (ANA), they bind to the cells (specifically the nuclei of the cells) on the slide. A second antibody, commercially tagged with a fluorescent dye, is added to the mix of patient's serum and commercially prepared cells on the slide. The second (fluorescent) antibody attaches to the serum antibodies and cells which have bound together. When viewed under an ultraviolet microscope, antinuclear antibodies appear as fluorescent cells. If fluorescent cells are observed, the ANA test is considered positive. If fluorescent cells are not observed, the ANA test is considered negative. The ANA titer is determined by repeating the positive test with serial dilutions until the test yields a negative result. The last dilution which yields a positive result (flourescence) is the titer which gets reported. For example, if a titer performed for a positive ANA test is: 1:10 positive 1:20 positive 1:40 positive 1:80 positive 1:160 positive 1:320 negative The reported titer would be 1:160. Generally, an ANA titre of 1:80 or higher is considered positive. At least 5% of the population has a positive ANA titre with no disease activity. For those with disease activity, the ANA titre does not indicate the absolute amount of disease activity (e.g. one person with an ANA titre of 1:640 may have very little disease activity, while another with a titre of 1:320 may have significant disease activity). The ANA titre must be evaluated in the context of the individual. The ANA test by itself is not specific for any disease. Your clinical presentation, as well as tests for additional antibodies, complements and factors in your blood will also be used to determine what condition, if any, is present, and how to treat it. Source(s): http://arthritis.about.com/od/diagnostic… webmd.com medhelp.org
Is a myocardial infarction a stroke?
A myocardial infarction is a heart attack. It is caused when the cells of the muscle of the heart do not get enough oxygen and glucose, resulting in anaerobic metabolism and buildup of products of that metabolism, resulting in cellular acidosis, shutdown of cellular metabolism, and finally cell death and necrosis. In the overwhelming number of casea, this process results from the blockage of a coronary artery by a thrombus formed when a cholesterol plaque ruptures, causing a clot to form. It can be caused by several other things, however. Severe dehydration, severe hypotension, partial blockage of an artery by a large plaque that has not ruptured and other low flow states can result in not enough oxygen and glucose getting to the cells. Also, anything that increases the metabolic demands on the heart muscle can cause similar effects - sepsis with shock, toxins, drugs, and poisonings.
How do tissues form your heart?
During embryonic development, part of the mesoderm breaks away and starts to form the heart. The embryonic stem cells differentiate primarily into myocardial cells, with the endoderm forming the endocardium and valves and the ectoderm forming the pericardium and pericardial sac. The exact steps aren't well known - embryology has more questions than answers for human development at this time.
What does depolarization of the heart mean?
It is a positive wave in the hearts muscle cells, the process of electrical discharge and the flow of electrical activity.
Why after dancing the heart rate stays fast for a long time?
In order to distribute oxygen to the muscle cells needed to dance, the blood must pump at an increased rate over the resting heart rate. At the end of exercise, there is still a defiency of oxygen and often anaerobic respiration (no oxygen present) takes place leaving lactic acid in the muscle cells. To return to baseline, the lactic acid must be removed by facilitating aerobic respiration (oxygen present).
