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February 10, 2012

Asthma Complexities Glossary of Terms

The following are health and medical definitions of terms that appear in the Asthma Complexities 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.
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ACE inhibitors: A drug that inhibits ACE (angiotensin converting enzyme) which is important to the formation of angiotensin II. Angiotensin II causes arteries in the body to constrict and thereby raises the blood pressure. ACE inhibitors lower the blood pressure by inhibiting the formation of angiotensin II. This relaxes the arteries. Relaxing the arteries not only lowers blood pressure, but also improves the pumping efficiency of a failing heart and improves cardiac output in patients with heart failure. ACE inhibitors are therefore used for blood pressure control and congestive heart failure.
See the entire definition of ACE inhibitors

Acid reflux: A common condition and an abnormal one in which acid in the stomach rises up into the esophagus. This occurs because the valve separating the contents of the stomach from the esophagus does not function properly. See also: GERD.

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.
See the entire definition of Acute

Acute bronchitis: inflammation of the breathing tubes within the lungs (bronchial tubes or bronchi) as a result of an infection (viral or bacterial) or a chemical irritant (such as smoke or gastric acid reflux). The inflammation causes swelling of the lining of these breathing tubes, narrowing the tubes and promoting secretion of inflammatory fluid. Most commonly, acute bronchitis is due to a viral infection. Common viruses that cause bronchitis include the rhinovirus, respiratory syncytial virus (RSV), and the influenza virus. Symptoms are a cough that begins abruptly and can include a runny nose, nasal stuffiness, and sore throat. As opposed to acute bronchitis, chronic bronchitis is a long-term condition with a daily cough with sputum production for at least three months, two years in a row. Cigarette smoking is a major risk factor for the development of both acute and chronic bronchitis. See also chronic bronchitis.

Adrenaline: A substance produced by the medulla (inside) of the adrenal gland, adrenaline (the official name in the British Pharmacopoeia) is synonymous with epinephrine. Technically speaking, adrenaline is a sympathomimetic catecholamine. It causes quickening of the heart beat, strengthens the force of the heart's contraction, opens up the bronchioles in the lungs and has numerous other effects. The secretion of adrenaline by the adrenal is part of the "fight-or-flight" reaction that we have in response to being frightened.

Airway: The path air follows to get into and out of the lungs. The mouth and nose are the normal entry and exit ports. Entering air then passes through the back of the throat (pharynx), continues through the voice box (larynx), down the trachea, and finally out the branching tubes known as bronchi.

Airway obstruction: Partial or complete blockage of the breathing tubes to the lungs. Obstruction of the airway can be due to different causes including foreign bodies, allergic reactions, infections, anatomical abnormalities and trauma.
See the entire definition of Airway obstruction

Allergic reaction: The hypersensitive response of the immune system of an allergic individual to a substance.
See the entire definition of Allergic reaction

Allergic rhinitis: Medical term for hay fever, a condition due to allergy that mimics a chronic cold. (Hay fever is a misnomer since hay is not a usual cause of this problem and there is no fever. Many substances cause the allergic symptoms in hay fever. Allergic rhinitis is the correct term for this allergic reaction. (Rhinitis means "irritation of the nose" and is a derivative of Rhino, meaning "nose.") Symptoms include nasal congestion, a clear runny nose, sneezing, nose and eye itching, and tearing eyes. Post-nasal dripping of clear mucus frequently causes a cough. Loss of smell is common and loss of taste occurs occasionally. Nose bleeding may occur if the condition is severe. Eye itching, redness, and tearing frequently accompany the nasal symptoms.

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.
See the entire definition of Allergy

Alpha-1: Short for alpha-1 antitrypsin deficiency.

Alveolar: Pertaining to the alveoli, the tiny air sacs in the lungs. The exchange of oxygen and carbon dioxide takes place in the alveoli which look like cells in a honeycomb.
See the entire definition of Alveolar

Alveoli: The plural of alveolus. The alveoli are tiny air sacs within the lungs where the exchange of oxygen and carbon dioxide takes place.

Anaphylaxis: Allergic reaction. In severe cases, this can include potentially deadly anaphylactic shock.

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Anatomy: The study of form. Gross anatomy involves structures that can be seen with the naked eye. It is as opposed to microscopic anatomy (or histology) which involves structures seen under the microscope. Traditionally, both gross and microscopic anatomy have been studied in the first year of medical school in the U.S. The most celebrated textbook of anatomy in the English-speaking world is Gray's Anatomy, still a useful reference book. The word "anatomy" comes from the Greek ana- meaning up or through + tome meaning a cutting. Anatomy was once a "cutting up" because the structure of the body was originally learned through dissecting it, cutting it up. The abbreviation for anatomy is anat.

Anxiety: A feeling of apprehension and fear characterized by physical symptoms such as palpitations, sweating, and feelings of stress. Anxiety disorders are serious medical illnesses that affect approximately 19 million American adults. These disorders fill people's lives with overwhelming anxiety and fear. Unlike the relatively mild, brief anxiety caused by a stressful event such as a business presentation or a first date, anxiety disorders are chronic, relentless, and can grow progressively worse if not treated.
See the entire definition of Anxiety

Apnea: An apnea is a period of time during which breathing stops or is markedly reduced. There are two types of apneas, the more common obstructive sleep apnea and the less common central sleep apnea.
See the entire definition of Apnea

Aspergillosis: Infection with the fungus Aspergillus, seen especially in people with a deficient immune system.
See the entire definition of Aspergillosis

Aspergillus: A family of fungal organisms and molds, some of which can cause disease (aspergillosis).

Aspiration: Removal of a sample of fluid and cells through a needle. Aspiration also refers to the accidental sucking in of food particles or fluids into the lungs.

Asthma: A common disorder in which chronic inflammation of the bronchial tubes (bronchi) makes them swell, narrowing the airways. Asthma involves only the bronchial tubes and does not affect the air sacs (alveoli) or the lung tissue (the parenchyma of the lung) itself.
See the entire definition of Asthma

Asthmatic: 1. Pertaining to asthma as, for example, asthmatic bronchitis.
2. A person with asthma.

Atopic: Prone to allergies or characterized by allergy.

Atopic dermatitis: A skin disease characterized by areas of severe itching, redness, scaling, and loss of the surface of the skin (excoriation). When the eruption (rash) has been present for a prolonged time, chronic changes occur due to the constant scratching and rubbing known as lichenification (thickening of the skin with accentuation of the skin lines to form a crisscross pattern).
See the entire definition of Atopic dermatitis

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

Bacterial: Of or pertaining to bacteria. For example, a bacterial lung infection.

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.

Bronchi: The large air tubes leading from the trachea to the lungs that convey air to and from the lungs. The bronchi have cartilage as part of their supporting wall structure. The trachea divides to form the right and left main bronchi which, in turn, divide to form the lobar, segmental, and finally the subsegmental bronchi.
See the entire definition of Bronchi

Bronchiectasis: Permanent dilatation (widening) of the bronchi (the large air tubes which begin at the bottom of the trachea and branch into the lungs). Bronchiectasis can result in very serious illness including recurrent respiratory infections, a disabling cough, shortness of breath, and hemoptysis (coughing up blood).
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Bronchitis: Inflammation and swelling of the bronchi. Bronchitis can be acute or chronic.
See the entire definition of Bronchitis

Bronchopulmonary: Pertaining to both the air passages (bronchi) leading to the lungs and the lungs (pulmonary) themselves.

Caffeine: A stimulant found naturally in coffee beans, tea leaves, cocoa beans (chocolate) and kola nuts (cola) and added to soft drinks, foods, and medicines. A cup of coffee has 100-250 milligrams of caffeine. Black tea brewed for 4 minutes has 40-100 milligrams. Green tea has one-third as much caffeine as black tea.
See the entire definition of Caffeine

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

Carbon dioxide: A gas which is the byproduct of cellular metabolism and which collects in the tissues, is cleared from the tissues by the blood within the veins, is carried by the hemoglobin in the red blood cells, and removed from the body via the lungs in the exhaled air. Abbreviated CO2.

Cardiac: Having to do with the heart.

Cardiovascular: The circulatory system comprising the heart and blood vessels which carries nutrients and oxygen to the tissues of the body and removes carbon dioxide and other wastes from them.
See the entire definition of Cardiovascular

Chest: The area of the body located between the neck and the abdomen. The chest contains the lungs, the heart and part of the aorta. The walls of the chest are supported by the dorsal vertebrae, the ribs, and the sternum.
See the entire definition of Chest

Chest X-ray: Commonly used to detect abnormalities in the lungs, but can also detect abnormalities in the heart, aorta, and the bones of the thoracic area. Metallic objects, such as jewelry are removed from the chest and neck areas for a chest x-ray to avoid interference with x-ray penetration and improve accuracy of the interpretation.

Chronic: This important term in medicine comes from the Greek chronos, time and means lasting a long time.
See the entire definition of Chronic

Chronic bronchitis: Defined clinically as a daily cough with production of sputum for 3 months, two years in a row.
See the entire definition of Chronic bronchitis

Circulatory: Having to do with the circulation, the movement of fluid in a regular or circuitous course. Although the adjective "circulatory" need not necessarily refer to the circulation of the blood, for all practical purposes today it does. A circulatory problem is taken usually to be a problem with the blood circulation, for example with heart failure.

Circulatory system: The system that moves blood throughout the body. The circulatory system is composed of the heart, arteries, capillaries, and veins. This remarkable system transports oxygenated blood from the lungs and heart throughout the body via the arteries. The blood goes through the capillaries which are situated between the arteries and veins. And the blood that has been depleted of oxygen by the body is then returned to the lungs and heart via the veins.

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.

COPD: Chronic obstructive pulmonary disease. Any disorder that persistently obstructs bronchial airflow. COPD mainly involves two related diseases -- chronic bronchitis and emphysema. Both cause chronic obstruction of air flowing through the airways and in and out of the lungs. The obstruction is generally permanent and progresses (becomes worse) over time.
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Cortisone: An adrenocorticoid hormone, a naturally occurring hormone made by and secreted by the adrenal cortex, the outer part (the cortex) of the adrenal gland.
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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.

Croup: A respiratory problem that occurs mainly in children, particularly from 2 to 4 years of age, due to an infection of the respiratory tree -- the larynx (voice box), the trachea (windpipe), and the bronchial tubes.
See the entire definition of Croup

Cure: 1. To heal, to make well, to restore to good health. Cures are easy to claim and, all too often, difficult to confirm.
2. A time without recurrence of a disease so that the risk of recurrence is small, as in the 5-year cure rate for malignant melanoma.
3. Particularly in the past, a course of treatment. For example, take a cure at a spa.
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Cystic fibrosis: One of the most common grave genetic (inherited) diseases, CF affects the exocrine glands and is characterized by the production of abnormal secretions, leading to mucous build-up.
See the entire definition of Cystic fibrosis

Dander: Tiny scales shed from human or animal skin or hair. Dander floats in the air, settles on surfaces and makes up much household dust. Cat dander is a classic cause of allergic reactions.

Dermatitis: Inflammation of the skin, either due to direct contact with an irritating substance, or to an allergic reaction. Symptoms of dermatitis include redness, itching, and in some cases blistering.
See the entire definition of Dermatitis

Diagnosis: 1 The nature of a disease; the identification of an illness. 2 A conclusion or decision reached by diagnosis. The diagnosis is rabies. 3 The identification of any problem. The diagnosis was a plugged IV.
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Diurnal: Occurring in the daytime. A patient may have a diurnal fever rather than a nocturnal one. Diurnal also can refer to recurring every day. Pronounced die-URN-ul, it comes from the Latin "dies" for day, the root of many words including circadian (about a day, about 24 hours), quotidian (which also means recurring every day), journal, etc.

Drain: A device for removing fluid from a cavity or wound. A drain is typically a tube or wick. As a verb, to allow fluid to be released from a confined area.

Drip: In medical usage, a drip is not a dull, unattractive person but a device for administering a fluid drop-by-drop into a vein. It is an intravenous (IV) fluid dripping into a vein, an intravenous fluid drip, a solution (usually a balanced electrolyte solution) administered directly into the venous circulation. It is, for short, an IV.

Dysfunction: Difficult function or abnormal function.
See the entire definition of Dysfunction

Dysphonia: An impairment of the voice. Difficulty in speaking. Hoarseness is a common sort of dysphonia. See also: Spasmodic dysphonia.

Ear: The hearing organ. There are three sections of the ear, according to the anatomy textbooks. They are the outer ear (the part we see along the sides of our head behind the temples), the middle ear, and the inner ear. But in terms of function, the ear has four parts: those three and the brain. Hearing thus involves all parts of the ear as well as the auditory cortex of the brain. The external ear helps concentrate the vibrations of air on the ear drum and make it vibrate. These vibrations are transmitted by a chain of little bones in the middle ear to the inner ear. There they stimulate the fibers of the auditory nerve to transmit impulses to the brain.
See the entire definition of Ear

Eczema: A particular type of inflammatory reaction of the skin in which there are typically vesicles (tiny blister-like raised areas) in the first stage followed by erythema (reddening), edema (swelling), papules (bumps), and crusting of the skin followed, finally, by lichenification (thickening) and scaling of the skin. Eczema characteristically causes itching and burning of the skin.
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Emphysema: 1) A lung condition featuring an abnormal accumulation of air in the lung's many tiny air sacs, a tissue called alveoli. As air continues to collect in these sacs, they become enlarged, and may break, or be damaged and form scar tissue. Emphysema is strongly associated with smoking cigarettes, a practice that causes lung irritation. It can also be associated with or worsened by repeated infection of the lungs, such as is seen in chronic bronchitis. The best response to the early warning signs of emphysema is prevention: stop smoking and get immediate treatment for incipient lung infections. Curing established emphysema is not yet possible. Because patients don't have an adequate amount of space in the lungs to breathe, they gasp for breath, and may not be able to obtain enough oxygen. Those with severe emphysema usually end up using an oxygen machine to breathe. In some cases, medication may be helpful to ease symptoms or to treat infection in already-damaged lungs.
See the entire definition of Emphysema

Enlarged heart: Enlargement of the heart. An enlarged heart is a descriptive term that is used to refer to the physical finding of an enlarged heart and is not a disease itself. Heart enlargement can be caused by a number of different conditions including diseases of the heart muscle or heart valves, high blood pressure, arrhythmias, and pulmonary hypertension. Enlarged heart can also sometimes accompany longstanding anemia and thyroid disease, among other conditions. Treatment and prognosis are dependent upon the underlying cause. Also referred to medically as cardiomegaly.

Enzyme: A protein (or protein-based molecule) that speeds up a chemical reaction in a living organism. An enzyme acts as catalyst for specific chemical reactions, converting a specific set of reactants (called substrates) into specific products. Without enzymes, life as we know it would not exist.
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Esophagus: The tube that connects the pharynx (throat) with the stomach. The esophagus lies between the trachea (windpipe) and the spine. It passes down the neck, pierces the diaphragm just to the left of the midline, and joins the cardiac (upper) end of the stomach. In an adult, the esophagus is about 25 centimeters (10 inches) long. When a person swallows, the muscular walls of the esophagus contract to push food down into the stomach. Glands in the lining of the esophagus produce mucus, which keeps the passageway moist and facilitates swallowing. Also known as the gullet or swallowing tube. From the Greek oisophagos, from oisein meaning to bear or carry + phagein, to eat.

Exercise-induced asthma: Asthma that is "triggered" by vigorous physical activity. Exercise-induced asthma tends particularly to affect children and young adults (because of their high level of physical activity) but can occur at any age.
See the entire definition of Exercise-induced asthma

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

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.
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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.).
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Formaldehyde: A pungent gas, with the chemical formula HCHO, used as an antiseptic, disinfectant, and especially today as a fixative for histology (the study of tissues under the microscope).
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Fungal: Pertaining to a fungus. For example, a fungal skin infection.

Fungi: Plural of fungus.

Gastroesophageal: Pertaining to both the stomach and the esophagus, as in the gastroesophageal junction, the place where the esophagus connects to the stomach.

Gastroesophageal reflux: The return of stomach contents back up into the esophagus This frequently causes heartburn because of irritation of the esophagus by stomach acid.
See the entire definition of Gastroesophageal reflux

Gastrointestinal: Adjective referring collectively to the stomach and small and large intestines.
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Genetic: Having to do with genes and genetic information.

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Genetic disease: A disease caused by an abnormality in an individual's genome.
See the entire definition of Genetic disease

GERD: Stands for Gastroesophageal Reflux Disease, a disorder in which there is recurrent return of stomach contents back up into the esophagus, frequently causing heartburn, a symptom of irritation of the esophagus by stomach acid. This can lead to scarring and stricture of the esophagus, which can require stretching (dilating).
See the entire definition of GERD

Globus: A word straight from the Latin, meaning (not unexpectedly) a globe or sphere. The word "globus" is used in a number of different contexts in medicine.
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Globus hystericus: The sensation of having a lump in the throat when there is nothing there. Sometimes simply called globus.
See the entire definition of Globus hystericus

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.
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Heart disease: Any disorder that affects the heart. Sometimes the term "heart disease" is used narrowly and incorrectly as a synonym for coronary artery disease. Heart disease is synonymous with cardiac disease but not with cardiovascular disease which is any disease of the heart or blood vessels. Among the many types of heart disease, see, for example: Angina; Arrhythmia; Congenital heart disease; Coronary artery disease (CAD); Dilated cardiomyopathy; Heart attack (myocardial infarction); Heart failure; Hypertrophic cardiomyopathy; Mitral regurgitation; Mitral valve prolapse; and Pulmonary stenosis.

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.
See the entire definition of Heart failure

Heart muscle: A type of muscle with unique features only found in the heart. The heart muscle, or cardiac muscle, is medically called the myocardium ("myo-" being the prefix denoting muscle).

Heartburn: An uncomfortable feeling of burning and warmth occurring in waves rising up behind the breastbone (sternum) toward the neck. It is usually due to gastroesophageal reflux disease (GERD), the rise of stomach acid back up into the esophagus. Heartburn has nothing whatsoever to do with the heart. It is a popular nonmedical term. It is medically called pyrosis.

HEPA: Acronym that stands for High-Efficiency Particulate Air and for High-Efficiency Particulate Arrestor.
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Hives: A raised, itchy area of skin that is usually a sign of an allergic reaction. It can be rounded or flat-topped but is always elevated above the surrounding skin. It reflects circumscribed dermal edema (local swelling of the skin). The hives are usually well circumscribed but may be coalescent and will blanch with pressure. They typically last less than 4 hours but they may stay for days or weeks. Approximately 20% of the population has experienced a bout of hives.
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Hoarseness: Hoarseness is a term referring to abnormal voice changes. Hoarseness may be manifested as a voice that sounds breathy, strained, rough, raspy, or a voice that has higher or lower pitch. There are many causes of hoarseness, including viral laryngitis, vocal cord nodules, laryngeal papillomas, gastroesophageal reflux-related laryngitis, and environmental irritants (such as tobacco smoking). An accumulation of fluid in the vocal cords associated with hoarseness has been termed Reinke's edema. Reinke's edema may occur as a result of cigarette smoking or voice abuse (prolonged or extended talking or shouting). Rarely, hoarseness results from serious conditions such as cancers of the head and neck region.

Hybrid: The word "hybrid" has a number of different biomedical meanings.
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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.
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Immunoglobulin: A protein produced by plasma cells and lymphocytes and characteristic of these types of cells. Immunoglobulins play an essential role in the body's immune system. They attach to foreign substances, such as bacteria, and assist in destroying them. Immunoglobulin is abbreviated Ig. The classes of immunoglobulins are termed immunoglobulin A (IgA), immunoglobulin G (IgG), immunoglobulin M (IgM), immunoglobulin D (IgD) and immunoglobulin E (IgE).

Immunoglobulin E: Abbreviated IgE. A class of immunoglobulins that includes the antibodies elicited by an allergic substance (allergen). A person who has an allergy usually has elevated blood levels of IgE. IgE antibodies attack and engage the invading army of allergens.

Immunologist: A person who is knowledgeable about immunology.

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.
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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.
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Insomnia: The perception or complaint of inadequate or poor-quality sleep because of one or more of the following: difficulty falling asleep; waking up frequently during the night with difficulty returning to sleep; waking up too early in the morning; or unrefreshing sleep. Insomnia is not defined by the number of hours of sleep a person gets or how long it takes to fall asleep. Individuals vary normally in their need for, and their satisfaction with, sleep. Insomnia may cause problems during the day, such as tiredness, a lack of energy, difficulty concentrating, and irritability.
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Lactose: The sugar found in milk. Lactose is a large sugar molecule that is made up of two smaller sugar molecules, glucose and galactose. In order for lactose to be absorbed from the intestine and into the body, it must first be split into glucose and galactose. The glucose and galactose are then absorbed by the cells lining the small intestine. The enzyme that splits lactose into glucose and galactose is called lactase, and it is located on the surface of the cells lining the small intestine.
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Lactose intolerance: Inability to digest lactose, a component of milk and most other dairy products. Lactose is sometimes also used as an ingredient in other foods, so those with a lactase deficiency should check labels carefully.
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Larynx: The larynx is the portion of the breathing, or respiratory, tract containing the vocal cords which produce vocal sound. It is located between the pharynx and the trachea. The larynx, also called the voice box, is a 2-inch-long, tube-shaped organ in the neck.


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Leukotriene: One of a group of hormones that cause the symptoms of hay fever and asthma. Derived from arachidonic acid, the leukotrienes act by mediating immediate hypersensitivity. Leukotriene modifiers that prevent the production or action of leukotrienes are used to treat hay fever and asthma.

Lung cancer: Cancer of the major organ of respiration - the lung. Lung cancer kills more men and women than any other form of cancer. Since the majority of lung cancer is diagnosed at a relatively late stage, only 10% of all lung cancer patients are ultimately cured. Eight out of 10 lung cancers are due to tobacco smoke. Lung cancers are classified as either small cell or non-small cell cancers. Persistent cough and bloody sputum can be symptoms of lung cancer. Lung cancer can be diagnosed based on examination of sputum, or tissue examination with biopsy using bronchoscopy, needle through the chest wall, or surgical excision.

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.

Mold: A very large group of microscopic fungi that live on plant or animal matter. Most are filamentous organisms and produce spores that can be air-, water-, or insect-borne. A common trigger for allergies.
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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.

Mucous: Pertaining to mucus, a thick fluid produced by the lining of some tissues of the body.
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Mucus: A thick slippery fluid produced by the membranes lining certain organs such as the nose, mouth, throat, and vagina. Mucus is the Latin word for "a semifluid, slimy discharge from the nose." Note that mucus is a noun while the adjective is mucous.

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."

Nasal: Having to do with the nose. Nasal drops are intended for the nose, not (for example) the eyes. The word "nasal" came from the Latin "nasus" meaning the nose or snout.

Nerve: A bundle of fibers that uses chemical and electrical signals to transmit sensory and motor information from one body part to another. See: Nervous system.

Neural: Having to do with nerve cells.

Nose: The external midline projection from the face.
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Obstruction: Blockage of a passageway. See, for example: Airway obstruction; Intestinal obstruction.

Onset: In medicine, the first appearance of the signs or symptoms of an illness as, for example, the onset of rheumatoid arthritis. There is always an onset to a disease but never to the return to good health. The default setting is good health.
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Oxygen: A colorless, odorless and tasteless gas that makes up about 20% of the air we breathe (and at least half the weight of the entire solid crust of the earth) and which combines with most of the other elements to form oxides. Oxygen is essential to human, animal and plant life.
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Ozone: A form of oxygen that consists of three atoms of oxygen, in contrast to normal atmospheric oxygen which consists of two atoms of oxygen. Ozone is an important greenhouse gas found in both the stratosphere and the troposphere. Ozone has effects beyond acting as a greenhouse gas. In the stratosphere, ozone provides a protective layer shielding the Earth from ultraviolet radiation and subsequent harmful health effect on humans and the environment. In the troposphere, oxygen molecules in ozone combine with other chemicals and gases (oxidization) to cause smog.
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Panic: A sudden strong feeling of fear that prevents reasonable thought or action.
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Pneumonia: Inflammation of one or both lungs with consolidation. Pneumonia is frequently but not always due to infection. The infection may be bacterial, viral, fungal or parasitic. Symptoms may include fever, chills, cough with sputum production, chest pain, and shortness of breath.

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.
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Psychotherapy: The treatment of a behavior disorder, mental illness, or any other condition by psychological means. Psychotherapy may utilize insight, persuasion, suggestion, reassurance, and instruction so that patients may see themselves and their problems more realistically and have the desire to cope effectively with them.
See the entire definition of Psychotherapy

Pulmonary: Having to do with the lungs. (The word comes from the Latin pulmo for lung).

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Radiograph: A film with an image of body tissues that was produced when the body was placed adjacent to the film while radiating with X-rays.

Recurrent: Back again. A recurrent fever is a fever that has returned after an intermission: a recrudescent fever.

Reflex: A reaction that is involuntary. The corneal reflex is the blink that occurs with irritation of the eye. The nasal reflex is a sneeze.

Reflux: The term used when liquid backs up into the esophagus from the stomach.

Regurgitation: A backward flowing. For example, of food. Or the sloshing of blood back into the heart (or between chambers of the heart) when a heart valve is incompetent and does not close effectively.

Respiratory: Having to do with respiration, the exchange of oxygen and carbon dioxide. From the Latin re- (again) + spirare (to breathe) = to breathe again.

Respiratory system: The organs that are involved in breathing. These include the nose, throat, larynx, trachea, bronchi, and lungs.

Rhinitis: Irritation of the nose. Derived from the Greek word rhinos meaning of the nose.

Shortness of breath: Difficulty in breathing. Medically referred to as dyspnea. Shortness of breath can be caused by respiratory (breathing passages and lungs) or circulatory (heart and blood vessels) conditions. See also dyspnea.

Sinusitis: Sinusitis is inflammation of the lining membrane of any of the hollow areas (sinuses) of the bone of the skull around the nose. The sinuses are directly connected to the nasal cavities.
See the entire definition of Sinusitis

Sleep: The body's rest cycle.
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Sleep apnea: The temporary stoppage of breathing during sleep, often resulting in daytime sleepiness. Apnea is a Greek word that means "want of breath."
See the entire definition of Sleep apnea

Sodium: The major positive ion (cation) in fluid outside of cells. The chemical notation for sodium is Na+. When combined with chloride, the resulting substance is table salt.
See the entire definition of Sodium

Sore: 1. (adjective) A popular term for painful. I have sore fingers from typing dictionary terms. She has a sore throat. 2. (noun) A nondescript term for nearly any lesion of the skin or mucous membranes. He has a number of sores in his mouth.

See the entire definition of Sore

Sore throat: Pain in the throat. Sore throat may be caused by many different causes, including inflammation of the larynx, pharynx, or tonsils.
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Spasm: A brief, automatic jerking movement. A muscle spasm can be quite painful, with the muscle clenching tightly. A spasm of the coronary artery can cause angina. Spasms in various types of tissue may be caused by stress, medication, over-exercise, or other factors.

Spastic dysphonia: See: Spasmodic dysphonia.

Speech therapy: The treatment of speech and communication disorders. The approach used depends on the disorder. It may include physical exercises to strengthen the muscles used in speech (oral-motor work), speech drills to improve clarity, or sound production practice to improve articulation.
See the entire definition of Speech therapy

Sputum: The mucus and other matter brought up from the lungs, bronchi, and trachea that one may cough up and spit out or swallow. The word "sputum" is borrowed directly from the Latin "to spit." Called also expectoration.

Stomach: 1. The sac-shaped digestive organ that is located in the upper abdomen, under the ribs. The upper part of the stomach connects to the esophagus, and the lower part leads into the small intestine.
See the entire definition of Stomach

Substance: 1. Material with particular features, as a pressor substance.
2. The material that makes up an organ or structure. Also known in medicine as the substantia.
3. A psychoactive drug as, for example, in substance abuse.

Surgery: The word "surgery" has multiple meanings. It is the branch of medicine concerned with diseases and conditions which require or are amenable to operative procedures. Surgery is the work done by a surgeon. By analogy, the work of an editor wielding his pen as a scalpel is s form of surgery. A surgery in England (and some other countries) is a physician's or dentist's office.
See the entire definition of Surgery

Symptom: Any subjective evidence of disease. Anxiety, lower back pain, and fatigue are all symptoms. They are sensations only the patient can perceive. In contrast, a sign is objective evidence of disease. A bloody nose is a sign. It is evident to the patient, doctor, nurse and other observers.

Therapy: The treatment of disease.
See the entire definition of Therapy

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.

Tobacco: A South American herb, formally known as Nicotiana tabacum, whose leaves contain 2-8% nicotine and serve as the source of smoking and smokeless tobacco.
See the entire definition of Tobacco

Trachea: A tube-like portion of the breathing or "respiratory" tract that connects the "voice box" (larynx) with the bronchial parts of the lungs.


See the entire definition of Trachea

Tracheostomy: A surgical operation to create an opening (stoma) into the windpipe (the trachea). The opening itself can also be called a tracheostomy.
See the entire definition of Tracheostomy

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.

Tubes: The "tubes" are medically known as the Fallopian tubes. There are two Fallopian tubes, one on each side, which transport the egg from the ovary to the uterus (the womb). The Fallopian tubes have small hair-like projections called cilia on the cells of the lining.
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Ventilation: The exchange of air between the lungs and the atmosphere so that oxygen can be exchanged for carbon dioxide in the alveoli (the tiny air sacs in the lungs).
See the entire definition of Ventilation

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.

Vocal cord: One of two small bands of muscle within the larynx. These muscles vibrate to produce the voice. The vocal cords form a "V" inside the larynx, a 2-inch-long, tube-shaped organ in the neck:

We use the larynx when we breathe, talk, or swallow. Its outer wall of cartilage forms the area of the front of the neck referred to as the "Adams apple."
See the entire definition of Vocal cord

Voice box: The voice box, or larynx, is the portion of the respiratory (breathing) tract containing the vocal cords which produce sound. It is located between the pharynx and the trachea. The larynx, also called the voice box, is a 2-inch-long, tube-shaped organ in the neck.


See the entire definition of Voice box

Wheezing: A whistling noise in the chest during breathing when the airways are narrowed or compressed.

X-ray: 1. High-energy radiation with waves shorter than those of visible light. X-rays possess the properties of penetrating most substances (to varying extents), of acting on a photographic film or plate (permitting radiography), and of causing a fluorescent screen to give off light (permitting fluoroscopy). In low doses X-rays are used for making images that help to diagnose disease, and in high doses to treat cancer. Formerly called a Roentgen ray. 2. An image obtained by means of X-rays.

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  • Related Diseases & Conditions

    • Sinus Infection
      • Sinus infection (sinusitis) signs and symptoms include headache, fever, and facial tenderness, pressure, or pain. Treatments of sinus infections are generally with antibiotics and at times, home remedies.
    • Chronic Obstructive Pulmonary Disease
      • COPD (chronic obstructive pulmonary disease) is a disorder that persistently obstructs bronchial airflow. COPD mainly involves three related conditions, chronic bronchitis, chronic asthma, and emphysema. Symptoms of COPD include chronic cough, shortness of breath, frequent respiratory infections, wheezing, morning headaches, and pulmonary hypertension. Treatment of COPD is focused on the related condition(s).
    • Asthma
      • Asthma is a common disorder in which chronic inflammation of the bronchial tubes (bronchi) makes them swell, narrowing the airways. Signs and symptoms include shortness of breath, chest tightness, cough and wheezing.
    • Emphysema
      • Emphysema is a progressive disease of the lungs. The primary cause of emphysema is smoking. Alpha 1-antitrypsin deficiency is a rare disorder that has a genetic predisposition to emphysema. Aging, IV drug use, immune deficiencies, and connect tissue illnesses are also risk factors for emphysema. Emphysema is a subtype of COPD (chronic obstructive pulmonary disease, COLD). Symptoms include shortness of breath and wheezing. Management of symptoms may be achieved with medications, quitting smoking, pulmonary rehabilitation, or surgery.
    • Chronic Bronchitis
      • Chronic bronchitis is a cough that occurs daily with production of sputum that lasts for at least three months, two years in a row. Causes of chronic bronchitis include cigarette smoking, inhaled irritants, and underlying disease processes (such as asthma, or congestive heart failure). Symptoms include cough, shortness of breath, and wheezing. Treatments include bronchodilators and steroids. Complications of chronic bronchitis include COPD and emphysema.
    • Steroid Drug Withdrawal
      • Corticosteroid drugs such as prednisone and prednisolone are commonly used to treat asthma, allergic reactions, RA, and IBD. Steroids such as these do have serious drawbacks such as steroid withdrawal symptoms such as: fatigue, weakness, decreased appetite, weight loss, nausea, vomiting, abdominal pain, and diarrhea. Speak with your healthcare provider prior to tapering off steroid medications.
    • Asthma: Over the Counter Treatment
      • Patients who have infrequent, mild bouts of asthma attacks may use over-the-counter (OTC) medications to treat their asthma symptoms. OTC asthma medicines are limited to epinephrine and ephedrine. These OTC drugs are best used with the guidance of a physician, as there may be side effects and the drugs may not be very effective.
    • Asthma in Children
      • Asthma, the main cause of chronic illness in children, has signs and symptoms in children that include frequent coughing spells, low energy while playing, complaints of chest "hurting," wheezing while breathing, shortness of breath, and feelings of tiredness. Treatment will involve a doctor creating an asthma action plan which will describe the use of asthma medications and when to seek emergency care for the child.
    • Asthma Medications
      • There are two types of asthma medications: long-term control with anti-inflammatory drugs and quick relief from bronchodilators. Asthma medicines may be inhaled using a metered dose inhaler or nebulizer or they may be taken orally. People with high blood pressure, diabetes, thyroid disease, or heart disease shouldn't take OTC drugs like Primatene Mist and Bronkaid.
    • Reflux Laryngitis
      • Acid backing up into the larynx (voice box), it causes reflux laryngitis. Irritation of the lining of the esophagus, larynx, and throat can lead to esophagitis, sinusitis, strictures, hoarseness, throat clearing, swallowing problems, asthma, chronic cough, and more. Typical symptoms of reflux laryngitis include heartburn, hoarseness, or a sensation of a foreign body in the throat. Reflux laryngitis can be treated with OTC medication, prescription medication, and lifestyle changes.
    • Biorhythms
      • Biologic rhythms, or biorhythms, are how our bodies respond to the regular phases of the sun, moon, and seasons. A medical chronobiologist studies how the "body clock" or biorhythms affect diseases and how the body clock responds to treatment of diseases and conditions at different times of the day.
    • Exercise-Induced Asthma
      • Exercise-induced asthma is asthma triggered by vigorous exercise. Symptoms include coughing, shortness of breath, chest tightness, wheezing, and fatigue while exercising. Preventing exercise-induced asthma attacks involves using inhaled medicines before exercising, performing warm-up exercises and cooling down afterward, avoiding exercising outdoors when pollen counts are high, restricting exercise when you have a viral infection, and wearing a mask over your nose and mouth when exercising in cold weather.
    • Secondhand Smoke
      • Secondhand smoke can cause illness and disease in nonsmokers. Some of these conditions include lung cancer, heart disease, respiratory illnesses such as asthma, SIDS, bronchitis, and pneumonia. Learn how you can protect yourself and your family from secondhand smoke exposure in the home environment and workplace.
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Asthma Complexities

What are biologic rhythms?

What are biologic rhythms? In essence, they're the rhythms of life. All forms of life on earth, including our bodies, respond rhythmically to the regular cycles of the sun, moon, and seasons.

For example, as night turns into day, vital body functions, including heart rate and blood pressure, speed up in anticipation of increased physical activity. These and other predictable fluctuations in body function, taking place during specific time cycles, are our biologic rhythms. They are regulated by "biologic clock" mechanisms located in the brain.

Although biologic rhythms can be "reprogrammed" by environmental influences (such as when a person regularly works the night shift and sleeps during the day), they are genetically "hard-wired" into our cells, tissues, and organs.

Medical chronobiologists have found that biologic rhythms can affect the severity of disease symptoms, diagnostic test results, and eve...

Read the Biorhythms article »







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