The following are health and medical definitions of terms that appear in the Interferon article.
Abdominal: Relating to the abdomen, the belly, that part of the body that contains all of the structures between the chest and the pelvis. The abdomen is separated anatomically from the chest by the diaphragm, the powerful muscle spanning the body cavity below the lungs. See the entire definition of Abdominal
Abdominal pain: Pain in the belly (the abdomen). Abdominal pain can come from conditions affecting a variety of organs. The abdomen is an anatomical area that is bounded by the lower margin of the ribs above, the pelvic bone (pubic ramus) below, and the flanks on each side. Although abdominal pain can arise from the tissues of the abdominal wall that surround the abdominal cavity (the skin and abdominal wall muscles), the term abdominal pain generally is used to describe pain originating from organs within the abdominal cavity (from beneath the skin and muscles). These organs include the stomach, small intestine, colon, liver, gallbladder, and pancreas. See the entire definition of Abdominal pain
Acetaminophen: A pain reliever and fever reducer. Brand name: Tylenol. The exact mechanism of action of acetaminophen is not known. Acetaminophen relieves pain by elevating the pain threshold (that is, by requiring a greater amount of pain to develop before it is felt by a person). Acetaminophen reduces fever through its action on the heat-regulating center (the "thermostat") of the brain. Generic is available.
Anorexia: An eating disorder characterized by markedly reduced appetite or total aversion to food. Anorexia is a serious psychological disorder. It is a condition that goes well beyond out-of-control dieting. The person with anorexia, most often a girl or young woman, initially begins dieting to lose weight. Over time, the weight loss becomes a sign of mastery and control. The drive to become thinner is thought to be secondary to concerns about control and fears relating to one's body. The individual continues the endless cycle of restrictive eating, often to a point close to starvation. This becomes an obsession and is similar to an addiction to a drug. Anorexia can be life-threatening. Also called anorexia nervosa.
Antihistamines: Drugs that combat the histamine released during an allergic reaction by blocking the action of the histamine on the tissue. Antihistamines do not stop the formation of histamine nor do they stop the conflict between the IgE and antigen. Therefore, antihistamines do not stop the allergic reaction but protect tissues from some of its effects. Antihistamines frequently cause mouth dryness and sleepiness. Newer "non sedating" antihistamines are generally thought to be somewhat less effective. Antihistamine side effects that very occasionally occur include urine retention in males and fast heart rate.
AZT: Zidovudine (formerly called azidothymidine [abbreviated AZT]), a drug used against human immunodeficiency virus (HIV), the virus that causes AIDS. The brand name is Retrovir. See the entire definition of AZT
Back pain: Pain felt in the low or upper back. There are many causes of back pain. See the entire definition of Back pain
Bacteria: Single-celled microorganisms which can exist either as independent (free-living) organisms or as parasites (dependent upon another organism for life). See the entire definition of Bacteria
Breathing: The process of respiration, during which air is inhaled into the lungs through the mouth or nose due to muscle contraction, and then exhaled due to muscle relaxation.
Cancer: An abnormal growth of cells which tend to proliferate in an uncontrolled way and, in some cases, to metastasize (spread). See the entire definition of Cancer
Cell: The basic structural and functional unit in people and all living things. Each cell is a small container of chemicals and water wrapped in a membrane. See the entire definition of Cell
Chills: feelings of coldness accompanied by shivering. Chills may develop after exposure to a cold environment or may accompany a fever.
Chronic: This important term in medicine comes from the Greek chronos, time and means lasting a long time. See the entire definition of Chronic
Congestion: An abnormal or excessive accumulation of a body fluid. The term is used broadly in medicine. Examples include nasal congestion (excess mucus and secretions in the air passages of the nose) seen with a common cold and congestion of blood in the lower extremities seen with some types of heart failure.
Cough: A rapid expulsion of air from the lungs typically in order to clear the lung airways of fluids, mucus, or material. Also called tussis.
Depression: An illness that involves the body, mood, and thoughts, that affects the way a person eats and sleeps, the way one feels about oneself, and the way one thinks about things. A depressive disorder is not the same as a passing blue mood. It is not a sign of personal weakness or a condition that can be wished away. People with a depressive disease cannot merely "pull themselves together" and get better. Without treatment, symptoms can last for weeks, months, or years. Appropriate treatment, however, can help most people with depression. See the entire definition of Depression
Diarrhea: A familiar phenomenon with unusually frequent or unusually liquid bowel movements, excessive watery evacuations of fecal material. The opposite of constipation. The word "diarrhea" with its odd spelling is a near steal from the Greek "diarrhoia" meaning "a flowing through." Plato and Aristotle may have had diarrhoia while today we have diarrhea. There are myriad infectious and noninfectious causes of diarrhea. See the entire definition of Diarrhea
Dizziness: Painless head discomfort with many possible causes including disturbances of vision, the brain, balance (vestibular) system of the inner ear, and gastrointestinal system. Dizziness is a medically indistinct term which laypersons use to describe a variety of conditions ranging from lightheadedness, unsteadiness to vertigo. See the entire definition of Dizziness
DNA: Deoxyribonucleic acid. One of two types of molecules that encode genetic information. (The other is RNA. In humans DNA is the genetic material; RNA is transcribed from it. In some other organisms, RNA is the genetic material and, in reverse fashion, the DNA is transcribed from it.) See the entire definition of DNA
Edema: The swelling of soft tissues as a result of excess water accumulation. See the entire definition of Edema
Enzymes: Proteins that act as a catalysts in mediating and speeding a specific chemical reaction. See the entire definition of Enzymes
Epithelial: Relating to the epithelium, the outside layer of cells that covers all the free, open surfaces of the body including the skin, and mucous membranes that communicate with the outside of the body.
Fatigue: A condition characterized by a lessened capacity for work and reduced efficiency of accomplishment, usually accompanied by a feeling of weariness and tiredness. Fatigue can be acute and come on suddenly or chronic and persist. See the entire definition of Fatigue
Fever: Although a fever technically is any body temperature above the normal of 98.6 degrees F. (37 degrees C.), in practice a person is usually not considered to have a significant fever until the temperature is above 100.4 degrees F (38 degrees C.). See the entire definition of Fever
Genes: The basic biological units of heredity. Segments of deoxyribonucleic acid (DNA) needed to contribute to a function. See the entire definition of Genes
Genital: Pertaining to the external and internal organs of reproduction. (Not to be confused with genetic.)
Hair loss: Hair loss is the thinning of hair on the scalp. The medical term for hair loss is alopecia. Alopecia can be temporary or permanent. The most common form of hair loss occurs gradually and is referred to as "androgenetic alopecia," meaning that a combination of hormones (androgens are male hormones) and heredity (genetics) is needed to develop the condition. Other types of hair loss include alopecia areata (patches of baldness that usually grow back), telogen effluvium (rapid shedding after childbirth, fever, or sudden weight loss); and traction alopecia (thinning from tight braids or ponytails). See the entire definition of Hair loss
Hairy cell leukemia: A form of chronic leukemia in which malignant B-lymphocytes (a type of white blood cell) are seen in the bone marrow, spleen, and peripheral blood and when viewed under the microscope, these cells appear to be covered with tiny hair-like projections. Hairy cell leukemia represents 2% of all leukemia. See the entire definition of Hairy cell leukemia
Headache: A pain in the head with the pain being above the eyes or the ears, behind the head (occipital), or in the back of the upper neck. Headache, like chest pain or back ache, has many causes. See the entire definition of Headache
Heart: The muscle that pumps blood received from veins into arteries throughout the body. It is positioned in the chest behind the sternum (breastbone; in front of the trachea, esophagus, and aorta; and above the diaphragm muscle that separates the chest and abdominal cavities. The normal heart is about the size of a closed fist, and weighs about 10.5 ounces. It is cone-shaped, with the point of the cone pointing down to the left. Two-thirds of the heart lies in the left side of the chest with the balance in the right chest. See the entire definition of Heart
Heart rate: The number of heart beats per unit time, usually per minute. The heart rate is based on the number of contractions of the ventricles (the lower chambers of the heart). The heart rate may be too fast (tachycardia) or too slow (bradycardia). The pulse is bulge of an artery from the wave of blood coursing through the blood vessel as a result of the heart beat. The pulse is often taken at the wrist to estimate the heart rate.
Hepatitis B: Inflammation of the liver due to the hepatitis B virus (HBV), once thought to be passed only through blood products. It is now known that hepatitis B can also be transmitted via needle sticks, body piercing and tattooing using un sterilized instruments, the dialysis process, sexual and even less intimate close contact, and childbirth. Symptoms include fatigue, jaundice, nausea, vomiting, dark urine, light stools. Diagnosis is by blood test. Treatment is via anti-viral drugs and/or hepatitis B immunoglobulin (HBIG). See the entire definition of Hepatitis B
Hepatitis C: Inflammation of the liver due to the hepatitis C virus (HCV), which is usually spread by blood transfusion, hemodialysis, and needle sticks. HCV causes most transfusion-associated hepatitis, and the damage it does to the liver can lead to cirrhosis and cancer. Transmission of the virus by sexual contact is rare. At least half of HCV patients develop chronic hepatitis C infection. Diagnosis is by blood test. Treatment is via anti-viral drugs. Chronic hepatitis C may be treated with interferon, sometimes in combination with anti-virals. There is no vaccine for hepatitis C. Previously known as non-A, non-B hepatitis.
Human papillomavirus: HPV. A family of over 100 viruses including those which cause warts and are transmitted by contact. Some types of HPV are associated with tumors of the genital tract including, notably, cancer of the cervix. See the entire definition of Human papillomavirus
Immune: Protected against infection. The Latin immunis means free, exempt.
Immune system: A complex system that is responsible for distinguishing us from everything foreign to us, and for protecting us against infections and foreign substances. The immune system works to seek and kill invaders. See the entire definition of Immune system
Interferon: A naturally occurring substance that interferes with the ability of viruses to reproduce. Interferon also boosts the immune system. See the entire definition of Interferon
Joint: A joint is the area where two bones are attached for the purpose of motion of body parts. A joint is usually formed of fibrous connective tissue and cartilage. An articulation or an arthrosis is the same as a joint. See the entire definition of Joint
Leukemia: Cancer of the blood cells. The growth and development of the blood cells are abnormal. Strictly speaking, leukemia should refer only to cancer of the white blood cells (the leukocytes) but in practice it can apply to malignancy of any cellular element in the blood or bone marrow, as in red cell leukemia (erythroleukemia). See the entire definition of Leukemia
Liver: An organ in the upper abdomen that aids in digestion and removes waste products and worn-out cells from the blood. The liver is the largest solid organ in the body. The liver weighs about three and a half pounds (1.6 kilograms). It measures about 8 inches (20 cm) horizontally (across) and 6.5 inches (17 cm) vertically (down) and is 4.5 inches (12 cm) thick.
Malaise: A vague feeling of discomfort, one that cannot be pinned down but is often sensed as "just not right." See the entire definition of Malaise
Malignant:1. Tending to be severe and become progressively worse, as in malignant hypertension. 2. In regard to a tumor, having the properties of a malignancy that can invade and destroy nearby tissue and that may spread (metastasize) to other parts of the body. See the entire definition of Malignant
Melanoma: The most dangerous form of skin cancer, a malignancy of the melanocyte, the cell that produces pigment in the skin. Melanoma is most common in people with fair skin, but can occur in people with all skin colors. Most melanomas present as a dark, mole-like spot that spreads and, unlike a mole, has an irregular border. The tendency toward melanoma may be inherited, and the risk increases with overexposure to the sun and sunburn. See the entire definition of Melanoma
Multiple sclerosis: Abbreviated MS. A disease of the central nervous system (CNS) marked by numbness, weakness, loss of muscle coordination, and problems with vision, speech, and bladder control. MS is an autoimmune disease in which the body's immune system attacks myelin, a key substance that serves as a nerve insulator and helps in the transmission of nerve signals. The progress, severity and specific symptoms in MS are unpredictable. One never knows when attacks will occur, how long they will last, or how severe they will be. Most people with MS are between the ages of 20 and 40 at the time of diagnosis. The term "multiple" refers to the multiple places in the CNS that are affected and to the multiple relapses and remissions characteristic of MS. See the entire definition of Multiple sclerosis
Muscle: Muscle is the tissue of the body which primarily functions as a source of power. There are three types of muscle in the body. Muscle which is responsible for moving extremities and external areas of the body is called "skeletal muscle." Heart muscle is called "cardiac muscle." Muscle that is in the walls of arteries and bowel is called "smooth muscle."
Myelogenous: Referring to the nonlymphocytic groups of white blood cells, including the granulocytes, monocytes and platelets. See the entire definition of Myelogenous
Nausea:Nausea, is the urge to vomit. It can be brought by many causes including, systemic illnesses, such as influenza, medications, pain, and inner ear disease. When nausea and/or vomiting are persistent, or when they are accompanied by other severe symptoms such as abdominal pain, jaundice, fever, or bleeding, a physician should be consulted.
Osteopetrosis: Thickening of the bones which become abnormally dense due an inherited defect in bone resorption -- the process in which old bone is broken down and removed so that new bone can be added to the skeleton. Osteoclasts are the cells responsible for bone resorption. In osteopetrosis the osteoclasts do not perform normally. This flaw in bone resorption results in bones that are abnormally dense, yet are fragile and easily broken. Men and women are equally affected by the disease. See the entire definition of Osteopetrosis
Pain: An unpleasant sensation that can range from mild, localized discomfort to agony. Pain has both physical and emotional components. The physical part of pain results from nerve stimulation. Pain may be contained to a discrete area, as in an injury, or it can be more diffuse, as in disorders like fibromyalgia. Pain is mediated by specific nerve fibers that carry the pain impulses to the brain where their conscious appreciation may be modified by many factors. See the entire definition of Pain
Perianal: Located around the anus, the opening of the rectum to the outside of the body. Peri- is a prefix borrowed from the Greek. It means "around or about." So pericardial is around the heart. Perinatal is around birth. And periumbilical is around the umbilicus (the belly button). Peri- is a useful prefix in anatomy and so is much employed in medicine. Pericardial fluid is fluid around the heart. Periaortic lymph nodes are lymph nodes around the aorta. A perianal abscess is an abscess (a local accumulation of pus) that forms next to the anus causing tender swelling in that area and pain on defecation.
Pharmacy: A location where prescription drugs are sold. A pharmacy is, by law, constantly supervised by a licensed pharmacist.
Platelet: An irregular, disc-shaped element in the blood that assists in blood clotting. During normal blood clotting, the platelets clump together (aggregate). Although platelets are often classed as blood cells, they are actually fragments of large bone marrow cells called megakaryocytes.
Platelet count: The calculated number of platelets in a volume of blood, usually expressed as platelets per cubic millimeter (cmm) of whole blood. Platelets are the smallest cell-like structures in the blood and are important for blood clotting and plugging damaged blood vessels. Platelet counts are usually done by laboratory machines that also count other blood elements such as the white and red cells. They can also be counted by use of a microscope. Normal platelet counts are in the range of 150,000 to 400,000 per microliter (or 150 - 400 x 109 per liter). These values many vary slightly between different laboratories.
Proteins: Large molecules composed of one or more chains of amino acids in a specific order determined by the base sequence of nucleotides in the DNA coding for the protein. See the entire definition of Proteins
Recombinant: A person with a new combination of genes, a combination of genes not present in either parent, due to parental recombination of those genes.
Recombinant DNA technology: A series of procedures used to join together (recombine) DNA segments. A recombinant DNA molecule is constructed (recombined) from segments from 2 or more different DNA molecules. Under certain conditions, a recombinant DNA molecule can enter a cell and replicate there, autonomously (on its own) or after it has become integrated into a chromosome.
Red blood cell: The blood cell that carries oxygen. Red cells contain hemoglobin and it is the hemoglobin which permits them to transport oxygen (and carbon dioxide). Hemoglobin, aside from being a transport molecule, is a pigment. It gives the cell its red color (and name). See the entire definition of Red blood cell
Suicidal: Pertaining to suicide. the taking of ones own life. As in a suicidal gesture, suicidal thought, or suicidal act. An "online lifeline for suicidal undergrads" may help prevent college students from committing suicide.
Thrombocytopenia: A low platelet count. Platelets are irregular, disc-shaped element in the blood that assists in blood clotting. thrombocytopenia can arise due to decreased production of platelets in the bone marrow or increased breakdown of platelets in the bloodstream, spleen, or liver. Thrombocytopenia is characterized by easy bruising and increased bleeding.
Toxicity: The degree to which a substance can harm humans or animals. See the entire definition of Toxicity
Triglycerides: The major form of fat stored by the body. A triglyceride consists of three molecules of fatty acid combined with a molecule of the alcohol glycerol. Triglycerides serve as the backbone of many types of lipids (fats). Triglycerides come from the food we eat as well as from being produced by the body. See the entire definition of Triglycerides
Viral: Of or pertaining to a virus. For example, "My daughter has a viral rash."
Viruses: Small living particles that can infect cells and change how the cells function. Infection with a virus can cause a person to develop symptoms. The disease and symptoms that are caused depend on the type of virus and the type of cells that are infected.
Leukemia is a type of cancer of the blood cells in which the growth and development of the blood cells are abnormal. Strictly speaking, leukemia should refer only to cancer of the white blood cells (the leukocytes) but in practice it can apply to malignancy of any cellular element in the blood or bone marrow, as in red cell leukemia (erythroleukemia).
HIV (human immunodeficiency virus) is the cause of AIDS (acquired immunodeficiency syndrome). HIV is a type of virus called a retrovirus, which infects humans when it comes in contact with a break in the skin or tissues such as those that line the vagina, anal area, mouth, or eyes.
Hepatitis C is an inflammation of the liver due to the hepatitis C virus (HCV), which is usually spread by
blood transfusion, hemodialysis, and needle sticks, especially with intravenous
drug abuse. Chronic hepatitis C may be treated with interferon, usually in combination with anti-virals.
Multiple sclerosis (MS) is a disease which progressively injures the nerves of the brain and spinal cord, reflected by alterations of virtually every sensory or motor function in the body. The cause of MS is primarily unknown. There are different types of MS including relapsing-remitting MS, primary-progressive MS, and secondary-progressive MS. Symptoms of MS rang from mild to severe and examples include visual disturbances, muscle weakness, spasm, and fatigue. Decreased concentration, memory loss, and impaired judgment. Treatment for MS is generally with medications.
There are several types of kidney cancer, including renal cell cancer (renal adenocarcinoma or hypernephroma), transitional cell carcinoma, and Wilms tumor. Symptoms of kidney cancer include blood in the urine, an abdominal lump or mass, chronic pain in the side, and tiredness. Treatment of kidney cancer--which may include surgery, arterial embolization, radiation therapy, biological therapy or chemotherapy--depends upon the stage of the disease and the patient's overall health.
Melanoma is a type of skin cancer which begins in skin cells called melanocytes and affects more than 53,600 people in the United States each year. These melanocytes can grow together to form benign moles which, after a change in size, shape, or color can be a sign of melanoma. Caused by sun exposure, early detection becomes extremely important to avoid a spread to other areas of the body. Diagnosis is confirmed through a biopsy of the abnormal skin and treatment depends on the extent and characteristics of the patient.
The hepatitis B virus is a unique, coated DNA virus belonging to the Hepadnaviridae family of viruses. The course of the virus is determined primarily by the age at which the infection is acquired and the interaction between the virus and the body's immune system. Successful treatment is associated with a reduction in liver injury and fibrosis (scarring), a decreased likelihood of developing cirrhosis and its complications, including liver cancer, and a prolonged survival.
A keloid is a scar that doesn't know when to stop. When the cells keep on reproducing, the result is an overgrown (hypertrophic) scar or a keloid. A keloid looks shiny and is often dome-shaped, ranging in color from slightly pink to red. It feels hard and thick and is always raised above the surrounding skin.
Human papillomavirus (HPV) infection is the most common sexually transmitted infection in the U.S. HPV is primarily transmitted by sexual contact. While some people develop warts in the genital region after infection, others experience no symptoms. Though genital warts can be removed, there is no cure for HPV infection. There is a vaccine to prevent infection from four common HPV types.
Pulmonary fibrosis is scarring throughout the lungs. Pulmonary fibrosis can be caused by many conditions including chronic inflammatory processes, infections, environmental agents, exposure to ionizing radiation, chronic conditions, and certain medications. Symptoms include shortness of breath, coughing, and diminished exercise tolerance. Treatment options are dependent on the type of pulmonary fibrosis; lung transplant and/or medications are optons.
Optic neuritis is inflammation of the optic nerve, the structure that connects the eye to the brain. The precise cause of optic neuritis is unknown, but it is thought to be a type of autoimmune disorder. Optic neuritis most commonly develops due to an autoimmune disorder that may be triggered by a viral infection.
A carcinoid tumor is a tumor that develops from enterochromaffin cells. The important characteristic of carcinoid tumors that sets them apart from other gastrointestinal tract tumors, is their potential to cause the carcinoid syndrome. Local symptoms may include abdominal pain, intestinal bleeding, and intestinal obstruction. However, often symptoms of the carcinoid syndrome can be more devastating than the local symptoms. There are many options for the treatment of carcinoid tumors and carcinoid syndrome.
AIDS is the advanced stage of HIV infection. Symptoms and signs of AIDS include pneumonia due to Pneumocystis jiroveci, tuberculosis, toxoplasmosis, seizures, weakness, meningitis, yeast infection of the esophagus, and Kaposi's sarcoma. Anti-retroviral therapy (HAART) is used in the treatment of AIDS.
Peyronie's disease is a condition characterized by a hard lump, or plaque, that forms within the penis. Symptoms of Peyronie's disease range from mild to severe. Treatment for Peyronie's disease includes medication, and often surgery.
The term 'hepatitis' simply means
inflammation of the liver. Hepatitis may be
caused by a virus or a toxin such as alcohol. Other viruses that can cause
injury to liver cells include the hepatitis A and
hepatitis C viruses. These
viruses are not related to each other or to hepatitis B virus and differ in
their structure, the ways they are spread among individuals, the severity of
symptoms they can cause, the way they are treated, and the outcome of the
infection.
What is the scope of the problem?
Hepatitis B is an infection of the liver caused by the
hepatitis B virus (HBV). It is estimated that 350 million individuals worldwide
are infected with the virus, which causes 620,000 deaths worldwide each year.
According to the Centers for Disease Control (CDC), approximately 46,000 new cases of hepatitis B
occurred in the United States in 2006.
In the United States, rates of new infection were highest
...