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Human immunodeficiency virus infection / acquired immunodeficiency syndrome (HIV/AIDS) is a disease of the human immune system caused by the human immunodeficiency virus (HIV).[1] During the initial infection a person may experience a brief period of influenza-like illness. This is typically followed by a prolonged period without symptoms. As the illness progresses it interferes more and more with the immune system, making people much more likely to get infections, including opportunistic infections, and tumors that do not usually affect people with working immune systems.
HIV is transmitted primarily via unprotected sexual intercourse (including anal and even oral sex), contaminated blood transfusions and hypodermic needles, and from mother to child during pregnancy, delivery, or breastfeeding.[2] Some bodily fluids, such as saliva and tears, do not transmit HIV.[3] Prevention of HIV infection, primarily through safe sex and needle-exchange programs, is a key strategy to control the spread of the disease. There is no cure or vaccine; however, antiretroviral treatment can slow the course of the disease and may lead to a near-normal life expectancy. While antiretroviral treatment reduces the risk of death and complications from the disease, these medications are expensive and may be associated with side effects.
Genetic research indicates that HIV originated in West-central Africa during the early twentieth century.[4] AIDS was first recognized by the Centers for Disease Control and Prevention (CDC) in 1981 and its cause—HIV infection—was identified in the early part of the decade.[5] Since its discovery, AIDS has caused nearly 30 million deaths (as of 2009).[6] As of 2010, approximately 34 million people have contracted HIV globally.[7] AIDS is considered a pandemic—a disease outbreak which is present over a large area and is actively spreading.[8]
HIV/AIDS has had a great impact on society, both as an illness and as a source of discrimination. The disease also has significant economic impacts. There are many misconceptions about HIV/AIDS such as the belief that it can be transmitted by casual non-sexual contact. The disease has also become subject to many controversies involving religion.
The purpose of an ELISA is to determine if a particular protein is present in a sample and if so, how much. There are two main variations on this method: you can determine how much antibody is in a sample, or you can determine how much protein is bound by an antibody. The distinction is whether you are trying to quantify an antibody or some other protein. In this example, we will use an ELISA to determine how much of a particular antibody is present in an individuals blood.
ELISAs are performed in 96-well plates which permits high throughput results. The bottom of each well is coated with a protein to which will bind the antibody you want to measure. Whole blood is allowed to clot and the cells are centrifuged out to obtain the clear serum with antibodies (called primary antibodies). The serum is incubated in a well, and each well contains a different serum (see figure below). A positive control serum and a negative control serum would be included among the 96 samples being tested.
Most folks remember puberty – and not always in a good way. It can be an awkward stage of budding breasts, unwanted hair, acne and unexpected body odor. Puberty, when a child undergoes physical changes and becomes sexually mature, typically begins around age 8 in girls and age 9 in boys. But imagine, say, a 6- or 7-year-old undergoing such changes? Studies are showing that the onset of puberty for both boys and girls is occurring earlier and earlier, a phenomenon defined as precocious puberty. A study published in Pediatrics in 2010 found that among a population of 1,200 American girls, about 23 percent of African-Americans,15 percent of Latinas and 10 percent of Caucasian girls had begun puberty (marked by breast development) at age 7. In 2012, another study published in Pediatrics found that puberty in American boys – measured by testicular enlargement and pubic hair growth – was beginning six months to two years earlier than what research in previous decades had documented, particularly among African-American children.
Lymphoma is cancer of the lymph system (or lymphatic system), which is part of our immunity. It is characterized by the formation of solid tumors in the immune system.1 The cancer affects immune cells called lymphocytes, which are white blood cells. Diagram of the lymphatic system The lymphatic system is a system of vessels that branch back from virtually all our tissues to drain excess fluids and present foreign material to the lymph nodes. Learn more about the lymphatic system here. Statistics from the US National Cancer Institute estimate that there are nearly 20 cases of non-Hodgkin's lymphoma for every 100,000 people in the American population.2 Hodgkin's lymphoma, meanwhile, is relatively rare, with around three cases in every 100,000 people.3
“Endo” is the Greek word for “inside” and “odont” is Greek for “tooth.” Endodontic treatment treats the inside of the tooth. Root canal treatment is one type of endodontic treatment. To understand endodontic treatment, it helps to know something about the anatomy of the tooth. Inside the tooth, under the white enamel and a hard layer called the dentin, is a soft tissue called the pulp. The pulp contains blood vessels, nerves, and connective tissue and creates the surrounding hard tissues of the tooth during development.
ADH's job is to act on the kidneys to promote water reabsorption. In this lesson, we'll compare and contrast diabetes insipidus, or DI, in which there is too little ADH, and syndrome of inappropriate antidiuretic hormone secretion , or SIADH, in which there is too much ADH.
Thoracic outlet syndrome affects the space between the collarbone and first rib (thoracic outlet). Common causes include trauma, repetitive injuries, pregnancy, and anatomical defects, such as having an extra rib. Symptoms include pain in the shoulders and neck and numbness, weakness, and coldness in the fingers. Treatment involves physical therapy and pain relief. In rare cases, surgery may be needed to relieve the compression.
When your arteries cannot supply enough blood to your heart, your doctor may recommend coronary artery bypass graft (CABG) surgery. One of the most common heart surgeries in the United States, CABG surgery restores blood flow to your heart. Approximately every 10 minutes, someone has beating heart or "off-pump" bypass surgery1. Beating heart bypass surgery is — in simple terms — bypass surgery that is performed on your heart while it is beating. Your heart will not be stopped during surgery. You will not need a heart-lung machine. Your heart and lungs will continue to perform during your surgery. Surgeons use a tissue stabilization system to immobilize the area of the heart where they need to work. Beating heart bypass surgery is also called Off Pump Coronary Artery Bypass Surgery (OPCAB). Both OPCAB and conventional on-pump surgery restore blood flow to the heart. However, off-pump bypass surgery has proven to reduce side effects in certain types of patients.
Hepatitis and chronic alcohol abuse are frequent causes. Liver damage caused by cirrhosis can't be undone, but further damage can be limited. Initially patients may experience fatigue, weakness, and weight loss. During later stages, patients may develop jaundice (yellowing of the skin), gastrointestinal bleeding, abdominal swelling, and confusion. Treatments focus on the underlying cause. In advanced cases, a liver transplant may be needed.