Pustular Psoriasis Glossary of Terms
The following are health and medical definitions of terms that appear in the Pustular Psoriasis article.
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. Absorb: 1. To take something in, as through the skin or the intestine. Acute: Of abrupt onset, in reference to a disease. Acute often also connotes an illness that is of short duration, rapidly progressive, and in need of urgent care. Albumin: The main protein in human blood and the key to the regulation of the osmotic pressure of blood. Chemically, albumin is soluble in water, precipitated by acid, and coagulated by heat. Allergy: A misguided reaction to foreign substances by the immune system, the body system of defense against foreign invaders, particularly pathogens (the agents of infection). The allergic reaction is misguided in that these foreign substances are usually harmless. The substances that trigger allergy are called allergen. Examples include pollens, dust mite, molds, danders, and certain foods. People prone to allergies are said to be allergic or atopic. Antibiotic: A drug used to treat infections caused by bacteria and other microorganisms. Originally, an antibiotic was a substance produced by one microorganism that selectively inhibits the growth of another. Synthetic antibiotics, usually chemically related to natural antibiotics, have since been produced that accomplish comparable tasks. Antidepressants: Anything, and especially a drug, used to prevent or treat depression. Antimalarial: A drug directed against malaria. The original antimalarial agent was quinine which took its name from the Peruvian Indian word "kina" meaning "bark of the tree." A large and complex molecule, quinine is the most important alkaloid found in cinchona bark. Until World War I, it was the only effective treatment for malaria. In fact, quinine was the first chemical compound to be successfully used to treat an infectious disease. Antipsoriatic: Directed against psoriasis. Sunlight is antipsoriatic, as are a number of drugs. Antiseptic: Something that discourages the growth microorganisms. By contrast, aseptic refers to the absence of microorganisms. Arms: An appendage in anatomy and in clinical trials. See: Arm. Arthritis: Inflammation of a joint. When joints are inflamed they can develop stiffness, warmth, swelling, redness and pain. There are over 100 types of arthritis. (see osteoarthritis, rheumatoid arthritis, ankylosing spondylitis, psoriatic arthritis, lupus, gout, pseudogout). Aspirin: A good example of a tradename that entered into the language, Aspirin was once the Bayer trademark for acetylsalicylic acid. Bacterial: Of or pertaining to bacteria. For example, a bacterial lung infection. Bile: Bile is a yellow-green fluid that is made by the liver, stored in the gallbladder and passes through the common bile duct into the duodenum where it helps digest fat. The principal components of bile are cholesterol, bile salts, and the pigment bilirubin. Blood count: The calculated number of white or red blood cells (WBCs or RBCs) in a cubic millimeter of blood. Blood culture: A test designed to detect if microorganisms such as bacteria and fungi are present in blood. A sample of blood obtained using sterile technique is placed in a culture media and incubated in a controlled environment for 1 to 7 days. If microorganisms grow, they can be identified as to type and tested against different antibiotics for proper treatment of the infection. Because microorganisms may only be intermittently present in blood, a series of 3 blood cultures is usually done before the result is considered negative. Blood pressure: The blood pressure is the pressure of the blood within the arteries. It is produced primarily by the contraction of the heart muscle. It's measurement is recorded by two numbers. The first (systolic pressure) is measured after the heart contracts and is highest. The second (diastolic pressure) is measured before the heart contracts and lowest. A blood pressure cuff is used to measure the pressure. Elevation of blood pressure is called "hypertension". Blood urea nitrogen: Abbreviated BUN. A measure primarily of the urea level in blood. Urea is cleared by the kidney. Diseases that compromise the function of the kidney frequently lead to an increased BUN. Bumps: The raised area of a bump or bruise results from blood leaking from these injured blood vessels into the tissues as well as from the body's response to the injury. A purplish, flat bruise that occurs when blood leaks out into the top layers of skin is referred to as an ecchymosis. Calcipotriene: A synthetic form of vitamin D3 that can be applied to the skin to treat psoriasis. Calcium: A mineral found mainly in the hard part of bones, where it is stored. Calcium is added to bones by cells called osteoblasts and is removed from bones by cells called osteoclasts. Calcium is essential for healthy bones. It is also important for muscle contraction, heart action, nervous system maintenance, and normal blood clotting. Food sources of calcium include dairy foods, some leafy green vegetables such as broccoli and collards, canned salmon, clams, oysters, calcium-fortified foods, and tofu. According to the National Academy of Sciences, adequate intake of calcium is 1,200 milligrams a day (four glasses of milk) for men and women 51 and older, 1,000 milligrams a day for adults 19 through 50, and 1,300 milligrams a day for children 9 through 18. The upper limit for calcium intake is 2.5 grams daily. Learn more about calcium with evidence-based information on RxList.Cancer: An abnormal growth of cells which tend to proliferate in an uncontrolled way and, in some cases, to metastasize (spread). CBC: A commonly used abbreviation in medicine that stands for complete blood count, a set values of the cellular (formed elements) of blood. These measurements are generally determined by specially designed machines that analyze the different components of blood in less than a minute. 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. 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. Clinical trials: Trials to evaluate the effectiveness and safety of medications or medical devices by monitoring their effects on large groups of people. Complete blood count: A set values of the cellular (formed elements) of blood. These measurements are generally determined by specially designed machines that analyze the different components of blood in less than a minute. Creatinine: A chemical waste molecule that is generated from muscle metabolism. Creatinine is produced from creatine, a molecule of major importance for energy production in muscles. Approximately 2% of the body's creatine is converted to creatinine every day. Creatinine is transported through the bloodstream to the kidneys. The kidneys filter out most of the creatinine and dispose of it in the urine. Cutaneous: Relating to the skin. As, for example, in cutaneous allodynia, a cutaneous papilloma, and cutaneous syndactyly. From the Latin cutis meaning skin. Dermatology: 1. The branch of medicine concerned with the diagnosis, treatment, and prevention of diseases of the skin, hair, nails, oral cavity and genitals. 2. Sometimes also, cosmetic care and enhancement. Dry skin: Abnormally dry skin. Can be caused by a dry climate, winter weather, deficiency of vitamin A, systemic illness, overexposure to sunlight, or medication. The skin loses moisture. It may crack and peel. Or it may become irritated, inflamed, and itch. Bathing frequently, especially with soaps, can contribute to dry skin. Erythrocyte: A cell that contains hemoglobin and can carry oxygen to the body. Also called a red blood cell (RBC). The reddish color is due to the hemoglobin. Erythrocytes are biconcave in shape, which increases the cell's surface area and facilitates the diffusion of oxygen and carbon dioxide. This shape is maintained by a cytoskeleton composed of several proteins. Erythrocytes are very flexible and change shape when flowing through capillaries. Immature erythrocytes, called reticulocytes, normally account for 1-2 percent of red cells in the blood. Erythrodermic psoriasis: A particularly inflammatory form of psoriasis that often affects most of the body surface. It is the least common form of psoriasis and most commonly appears on people who have unstable plaque psoriasis, where lesions are not clearly defined. The erythrodermic form of psoriasis is characterized by periodic, widespread, fiery redness of the skin. The erythema (reddening) and exfoliation (shedding) of the skin are often accompanied by severe itching and pain. Swelling may also develop. FDA: The Food and Drug Administration, an agency within the U.S. Public Health Service, which is a part of the Department of Health and Human Services. 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.). Gastrointestinal: Adjective referring collectively to the stomach and small and large intestines. Gastrointestinal tract: The tube that extends from the mouth to the anus in which the movement of muscles and release of hormones and enzymes digest food. The gastrointestinal tract starts with the mouth and proceeds to the esophagus, stomach, duodenum, small intestine, large intestine (colon), rectum and, finally, the anus. Also called the alimentary canal, digestive tract and, perhaps most often in conversation, the GI tract. Generic: 1. The chemical name of a drug. 2. A term referring to the chemical makeup of a drug rather than to the advertised brand name under which the drug may be sold. 3.A term referring to any drug marketed under its chemical name without advertising. Generic drug: The term "generic" has several meanings as regards drugs:
See the entire definition of Generic drug Genital: Pertaining to the external and internal organs of reproduction. (Not to be confused with genetic.) Guttate psoriasis: A type of psoriasis characterized by red, scaly patches of inflamed skin on all parts of the body. It is associated with a lung infection in many cases. 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). 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. 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. Heart failure: Inability of the heart to keep up with the demands on it and, specifically, failure of the heart to pump blood with normal efficiency. When this occurs, the heart is unable to provide adequate blood flow to other organs such as the brain, liver and kidneys. Heart failure may be due to failure of the right or left or both ventricles. The signs and symptoms depend upon which side of the heart is failing. They can include shortness of breath (dyspnea), asthma due to the heart (cardiac asthma), pooling of blood (stasis) in the general body (systemic) circulation or in the liver's (portal) circulation, swelling (edema), blueness or duskiness (cyanosis), and enlargement (hypertrophy) of the heart. High blood pressure: Also known as hypertension, high blood pressure is, by definition, a repeatedly elevated blood pressure exceeding 140 over 90 mmHg -- a systolic pressure above 140 with a diastolic pressure above 90. Hypoalbuminemia: An abnormally low blood level of albumin. Normally, albumin is the most plentiful protein in human blood and the key to the regulation of its osmotic pressure. Hypocalcemia: Lower-than-normal blood calcium. Low blood calcium makes the nervous system highly irritable with tetany (spasms of the hands and feet, muscle cramps, abdominal cramps, and overly active reflexes). Chronic hypocalcemia contributes to poor mineralization of bones, soft bones (osteomalacia) and osteoporosis. In children, hypocalcemia leads to rickets and impaired growth. Food sources of calcium include dairy foods, some leafy green vegetables such as broccoli and collards, canned salmon, clams, oysters, calcium-fortified foods, and tofu. According to the National Academy of Sciences, adequate intake of calcium is 1 gram daily for both men and women. The upper limit for calcium intake is 2.5 grams daily. 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. Indication: 1. In medicine, a condition which makes a particular treatment or procedure advisable. CML (chronic myeloid leukemia) is an indication for the use of Gleevec (imatinib mesylate). 2. A sign or a circumstance which points to or shows the cause, pathology, treatment, or outcome of an attack of disease. The presence of the Philadelphia chromosome in peripheral blood cells is an indication of a relapse in CML. Infection: The growth of a parasitic organism within the body. (A parasitic organism is one that lives on or in another organism and draws its nourishment therefrom.) A person with an infection has another organism (a "germ") growing within him, drawing its nourishment from the person. Inflammation: A basic way in which the body reacts to infection, irritation or other injury, the key feature being redness, warmth, swelling and pain. Inflammation is now recognized as a type of nonspecific immune response. Interferon: A naturally occurring substance that interferes with the ability of viruses to reproduce. Interferon also boosts the immune system. Iodine: An essential element in the diet used by the thyroid gland to make thyroid hormones. Itching: An uncomfortable sensation in the skin that feels as if something is crawling on the skin or in the skin, and makes the person want to scratch the affected area. Jaundice: Yellow staining of the skin and sclerae (the whites of the eyes) by abnormally high blood levels of the bile pigment bilirubin. The yellowing extends to other tissues and body fluids. Jaundice was once called the "morbus regius" (the regal disease) in the belief that only the touch of a king could cure it. 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. Juvenile: Between infantile and adult as, for example, in juvenile rheumatoid arthritis (onset before age 16 years) and juvenile diabetes (type 1 diabetes). Kidney: One of a pair of organs located in the right and left side of the abdomen which clear "poisons" from the blood, regulate acid concentration and maintain water balance in the body by excreting urine. The kidneys are part of the urinary tract. The urine then passes through connecting tubes called "ureters" into the bladder. The bladder stores the urine until it is released during urination. See the entire definition of Kidney Leukocytosis: Increase in the number of white blood cells. Lithium: Lithium carbonate (brand names: Eskalith; Lithobid), a drug used as a mood stabilizer for the treatment of manic/depressive (bipolar) disorder. It prevents or diminishes the intensity of episodes of mania in bipolar patients. Typical symptoms of mania include pressure of speech, motor hyperactivity, reduced need for sleep, flight of ideas, grandiosity, elation, poor judgment, aggressiveness and possibly hostility. 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. See the entire definition of Liver Lungs: The lungs are a pair of breathing organs located with the chest which remove carbon dioxide from and bring oxygen to the blood. There is a right and left lung. Lymphoma: Tumor of the lymphoid tissue. Diagnosis is by biopsy. Treatment may be chemotherapy, radiation, surgery, or medication, depending on the age of the patient and type of tumor. Malabsorption: The impaired absorption by the intestines of nutrients from food. Malabsorption can be specific and involve sugars, fats, proteins, or vitamins. Alternatively, malabsorption can be general and nonspecific. Malignancy: A tumor that is malignant, that is cancerous, that can invade and destroy nearby tissue, and that may spread (metastasize) to other parts of the body. Malnutrition: A term used to refer to any condition in which the body does not receive enough nutrients for proper function. Malnutrition may range from mild to severe and life-threatening. It can be a result of starvation, in which a person has an inadequate intake of calories, or it may be related to a deficiency of one particular nutrient (for example, vitamin C deficiency). Malnutrition can also occur because a person can not properly digest or absorb nutrients from the food they consume, as may occur with certain medical conditions. Malnutrition remains a significant global problem, especially in developing countries. Methotrexate: A drug that acts as an antimetabolite and specifically as a folic acid antagonist that inhibits the synthesis of DNA, RNA, and protein. Mouth: 1. The upper opening of the digestive tract, beginning with the lips and containing the teeth, gums, and tongue. Foodstuffs are broken down mechanically in the mouth by chewing and saliva is added as a lubricant. Saliva contains amylase, an enzyme that digests starch. 2. Any opening or aperture in the body. The mouth in both senses of the word is also called the os, the Latin word for an opening, or mouth. The o in os is pronounced as in hope. The genitive form of os is oris from which comes the word oral. Nail: In medicine, there are two types of nails. One is just a plain old metal nail used to hold 2 or more pieces of bone together, for example, after a fracture. The other type of nail is the horny plate on the end of the finger or toe. Each nail anatomically has a body, lateral nail folds (on the sides), a lunula (the little moon-shaped feature at the base), and a proximal skin fold (at the base). 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. Necrosis: The death of living cells or tissues. Necrosis can be due, for example, to ischemia (lack of blood flow). From the Greek "nekros" (dead body). Nitrogen: Element number 7, a colorless, odorless, tasteless gas that is biologically important. Nitrogen is a constituent of protein and nucleic acids and is present in all living cells. Nitrogen does not support respiration and is fatal if breathed alone, because of the lack of oxygen. Nitrogen is soluble in the blood and body fluids and, when released as bubbles of gas, can have serious or even fatal consequences. Occlusion: The act of occluding. See: Occlude. Ointment: A medication preparation that is applied topically (onto the skin). An ointment has an oil base whereas a cream is water-soluble. (The word ointment comes from the Latin ungere meaning anoint with oil). Outpatient: A patient who is not an inpatient (not hospitalized) but instead is cared for elsewhere -- as in a doctor's office, clinic, or day surgery center. The term outpatient dates back at least to 1715. Outpatient care today is also called ambulatory care. 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. Penicillin: The most famous of all antibiotics, named for the fungal mold Penicillium notatum from which it is derived. Penicillin acts by destroying the cell wall of bacteria. Pharmacy: A location where prescription drugs are sold. A pharmacy is, by law, constantly supervised by a licensed pharmacist. Phototherapy: Treatment with light. For example, a newborn with jaundice may be "put under the lights." Plaque: 1. An semi-hardened accumulation of substances from fluids that bathe an area. Examples include dental plaque and cholesterol plaque. Plaque psoriasis: The most common form of psoriasis -- about 80% of people with psoriasis have this type. Plaque psoriasis can appear on any skin surface, although the knees, elbows, scalp, trunk and nails are the most common locations. It is characterized by well-defined patches of red raised skin. The flaky silvery white buildup on top of the plaques is called scale; it is composed of dead skin cells. This scale comes loose and sheds constantly from the plaques. Skin affected with psoriasis is generally very dry, and other possible symptoms include skin pain, itching and cracking. The technical name for plaque psoriasis is psoriasis vulgaris (vulgaris means common). Plasma: The liquid part of the blood and lymphatic fluid, which makes up about half of its volume. Plasma is devoid of cells and, unlike serum, has not clotted. Blood plasma contains antibodies and other proteins. It is taken from donors and made into medications for a variety of blood-related conditions. Some blood plasma is also used in non-medical products. Pregnancy: The state of carrying a developing embryo or fetus within the female body. This condition can be indicated by positive results on an over-the-counter urine test, and confirmed through a blood test, ultrasound, detection of fetal heartbeat, or an X-ray. Pregnancy lasts for about nine months, measured from the date of the woman's last menstrual period (LMP). It is conventionally divided into three trimesters, each roughly three months long. Pregnant: The state of carrying a developing fetus within the body. Prescription: A physician's order for the preparation and administration of a drug or device for a patient. A prescription has several parts. They include the superscription or heading with the symbol "R" or "Rx", which stands for the word recipe (meaning, in Latin, to take); the inscription, which contains the names and quantities of the ingredients; the subscription or directions for compounding the drug; and the signature which is often preceded by the sign "s" standing for signa (Latin for mark), giving the directions to be marked on the container. Prognosis: 1. The expected course of a disease. Protein: A large molecule 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. Psoralen: Any of a number of drugs and other substances containing chemicals that react with ultraviolet (UV) light to cause darkening of the skin. Psoriasis: A reddish, scaly rash often located over the surfaces of the elbows, knees, scalp, and around or in the ears, navel, genitals or buttocks. Psoriasis is an autoimmune disease that is mediated by T lymphocytes. It is also a very common disease, Chronic plaque psoriasis affects approximately 2% of people around the world. About 10-15% of patients with psoriasis develop joint inflammation (inflammatory arthritis). Treatment options include topical steroid creams, tar soap preparations, and exposure to ultraviolet light. Psoriatic arthritis: Joint inflammation associated with psoriasis. Psoriatic arthritis is a potentially destructive and deforming form of arthritis that affects approximately 10% of persons with psoriasis. Pus: A thick whitish-yellow fluid which results from the accumulation of white blood cells (WBCs), liquified tissue and cellular debris. Pus is commonly a site of infection or foreign material in the body. Pustular psoriasis: A type of recurring psoriasis characterized by the appearance of pus-filed pimples and sores in clusters. It can be intensely painful, and hospitalization may be required. Pustulosis: A highly inflammatory skin condition resulting in large fluid-filled blister-like areas (pustules). Pustulosis typically occurs on the palms of the hands and/or the soles of the feet. The skin of these areas peels and flakes (exfoliates). PUVA: PUVA stands for psoralen (P) and ultraviolet A (UVA) therapy in which the patient is exposed first to psoralens (drugs containing chemicals that react with ultraviolet light) and then to UVA light. Rash: Breaking out (eruption) of the skin. Medically, a rash is referred to as an exanthem. 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. Recurrent: Back again. A recurrent fever is a fever that has returned after an intermission: a recrudescent fever. Red blood cells: The blood cells that carry 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 cells their red color (and their name). Regimen: With the accent on the first syllable (reg as in Reggie Jackson), a regimen is a plan, a regulated course such as a diet, exercise or treatment, designed to give a good result. A low-salt diet is a regimen. Registry: Although a registry was originally the place (like Registry House in Edinburgh) where information was collected (in registers), the word registry has also come to mean the collection itself. A registry is usually organized so the data can be analyzed. For example, analysis of data in a tumor registry maintained at a hospital may show a rise in lung cancer among women. Remission: Disappearance of the signs and symptoms of cancer or other disease. When this happens, the disease is said to be "in remission." A remission can be temporary or permanent. Renal: Having to do with the kidney. From the Latin renes (the kidneys), which gave the French les reins which mean both the kidneys and the lower back. Resistance: Opposition to something, or the ability to withstand it. For example, some forms of staphylococcus are resistant to treatment with antibiotics. Respiratory: Having to do with respiration, the exchange of oxygen and carbon dioxide. From the Latin re- (again) + spirare (to breathe) = to breathe again. Retinoid: 1. Vitamin A (retinol) or a naturally occurring or synthetic substance chemically related to it. (Retinoid literally means "like retinol.") Risk factor: Something that increases a person's chances of developing a disease. Salicylic acid: A substance obtained from plants (white willow back and wintergreen leaves) and also synthesized which is versatile and possesses bacteriostatic, fungicidal, and keratolytic actions. Saline: Relating to salt. As an adjective, "saline" means "salty, containing salt." As a noun "saline" is a salt solution, often adjusted to the normal salinity of the human body. Sedimentation rate: A blood test that detects and monitors inflammation in the body. It measures the rate at which red blood cells (RBCs) in a test tube separate from blood serum over time, becoming sediment in the bottom of the test tube. The sedimentation rate increases with more inflammation. Also called the erythrocyte sedimentation rate. Abbreviated as sed rate or ESR. Sensitivity: 1. In psychology, the quality of being sensitive. As, for example, sensitivity training, training in small groups to develop a sensitive awareness and understanding of oneself and of ones relationships with others. 2. In disease epidemiology, the ability of a system to detect epidemics and other changes in disease occurrence. 3. In screening for a disease, the proportion of persons with the disease who are correctly identified by a screening test. 4. In the definition of a disease, the proportion of persons with the disease who are correctly identified by defined criteria. Serum: The clear liquid that can be separated from clotted blood. Serum differs from plasma, the liquid portion of normal unclotted blood containing the red and white cells and platelets. It is the clot that makes the difference between serum and plasma. Sperm: A sperm is the male "gamete" or sex cell. It combines with the female "gamete," called an ovum, to form a zygote. The formation process is called "fertilization." (see ovum, zygote). Steroid: A general class of chemical substances that are structurally related to one another and share the same chemical skeleton (a tetracyclic cyclopenta[a]phenanthrene skeleton). Strain: 1. An injury to a tendon or muscle resulting from overuse or trauma. 2. A hereditary tendency that originated from a common ancestor. 3. To exert maximum effort. 4. To filter. Stress: Forces from the outside world impinging on the individual. Stress is a normal part of life that can help us learn and grow. Conversely, stress can cause us significant problems. Subacute: Rather recent onset or somewhat rapid change. The term "subacute" is used in contrast to acute which indicates very sudden onset or rapid change and chronic which indicates indefinite duration or virtually no change. A chronic condition is one lasting 3 months or more, by the definition of the U.S. National Center for Health Statistics. In ancient Greece, the "father of medicine" Hippocrates distinguished diseases that were acute (abrupt, sharp and brief) from those that were chronic. This is still a very useful distinction. Subacute has been coined to designate the mid-ground between acute and chronic. Substance: 1. Material with particular features, as a pressor substance. Sunburn: Sunburn is an inflammation of the skin that develops in response to exposure to ultraviolet (UV) radiation from the sun or from tanning beds and booths that emit UV radiation. Sunburn is manifested by reddened, painful skin that may develop blisters. Syndrome: A set of signs and symptoms that tend to occur together and which reflect the presence of a particular disease or an increased chance of developing a particular disease. Systemic: Affecting the entire body. A systemic disease such as diabetes can affect the whole body. Systemic chemotherapy employs drugs that travel through the bloodstream and reach and affect cells all over the body. Systemic therapy: Treatment that reaches cells throughout the body by traveling through the bloodstream. Therapy: The treatment of disease. Thigh: The thigh extends from the hip to the knee. The thigh has only one bone, the femur which is the largest bone in the human body. Throat: The throat is the anterior (front) portion of the neck beginning at the back of the mouth, consisting anatomically of the pharynx and larynx. The throat contains the trachea and a portion of the esophagus. Tongue: The tongue is a strong muscle anchored to the floor of the mouth. It is covered by the lingual membrane which has special areas to detect tastes. Topical: Pertaining to a particular surface area. A topical agent is applied to a certain area of the skin and is intended to affect only the area to which it is applied. Whether its effects are indeed limited to that area depends upon whether the agent stays where it is put or is absorbed into the blood stream. Toxicity: The degree to which a substance can harm humans or animals. Trigger: Something that either sets off a disease in people who are genetically predisposed to developing the disease, or that causes a certain symptom to occur in a person who has a disease. For example, sunlight can trigger rashes in people with lupus. Tzanck test: The examination of fluid from a bulla (a blister) in search of Tzanck cells characteristic of varicella (chickenpox), herpes zoster, herpes simplex, and pemphigus vulgaris. Named for a Russian dermatologist Arnault Tzanck (1886-1954). Urea: A nitrogen-containing substance normally cleared from the blood by the kidney into the urine. Diseases that compromise the function of the kidney often lead to increased blood levels of urea, as measured by the blood urea nitrogen (BUN) test. Urine: Liquid waste. The urine is a clear, transparent fluid. It normally has an amber color. The average amount of urine excreted in 24 hours is from 40 to 60 ounces (about 1,200 cubic centimeters). Chemically, the urine is mainly an aqueous (watery) solution of salt (sodium chloride) and substances called urea and uric acid. Normally, it contains about 960 parts of water to 40 parts of solid matter. Abnormally, it may contain sugar (in diabetes), albumen (a protein) (as in some forms of kidney disease), bile pigments (as in jaundice), or abnormal quantities of one or another of its normal components. Viral: Of or pertaining to a virus. For example, "My daughter has a viral rash." Vitamin D: A steroid vitamin which promotes the intestinal absorption and metabolism of calcium and phosphorus. Under normal conditions of sunlight exposure, no dietary supplementation is necessary because sunlight promotes adequate vitamin D synthesis in the skin. Deficiency can lead to bone deformity (rickets) in children and bone weakness (osteomalacia) in adults. White blood cell: One of the cells the body makes to help fight infections. There are several types of white blood cells (leukocytes). The two most common types are the lymphocytes and neutrophils (also called polymorphonuclear leukocytes, PMNs, or "polys"). Zinc: A mineral essential to the body, zinc is a constituent of many enzymes that permit chemical reactions to proceed at normal rates. It is involved in the manufacture of protein (protein synthesis) and in cell division. Zinc is also a constituent of insulin, and is concerned with the sense of smell.
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Pustular Psoriasis
Types of Psoriasis Overview
Psoriasis is a chronic disease of the skin that affects approximately 5.5 million people in the United States. Typical characteristics of psoriasis are red, dry, patches of skin and inflammation. Psoriasis is not contagious and can be inherited. A brief overview of each type is provided below.
Plaque Psoriasis
Plaque psoriasis is the most common type of psoriasis. Approximately, 9 out of 10 people with psoriasis have plaque psoriasis. The skin is red and covered with silvery scales. Circular- to oval-shaped red plaques that sometimes itch or burn are typical of plaque psoriasis. The patches usually are found on the elbows, knees, trunk, or scalp but may be found on any part of the skin. Most plaques of psoriasis are persistent (they stay for years and do not tend to come and go).
Plaqu...
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