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February 10, 2012


Alzheimer's Disease Glossary of Terms

The following are health and medical definitions of terms that appear in the Alzheimer's Disease article.

Abnormal: Not normal. Deviating from the usual structure, position, condition, or behavior. In referring to a growth, abnormal may mean that it is cancerous or premalignant (likely to become cancer).

Acetylcholine: A key chemical in neurons (nerve cells) that acts as a neurotransmitter and carries information across the synaptic cleft, the space between two nerve cells. Abbreviated ACh.

Aging: The process of becoming older, a process that is genetically determined and environmentally modulated.
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Alzheimer's disease: A progressive neurologic disease of the brain that leads to the irreversible loss of neurons and dementia. The clinical hallmarks of Alzheimer's disease are progressive impairment in memory, judgment, decision making, orientation to physical surroundings, and language. A working diagnosis of Alzheimer disease is usually made on the basis of the neurologic examination. A definitive diagnosis can be made only at autopsy. On a cellular level, Alzheimer's disease is characterized by unusual helical protein filaments in nerve cells (neurons) of the brain. These odd twisted filaments are called neurofibrillary tangles. On a functional level, there is degeneration of the cortical regions, especially the frontal and temporal lobes, of the brain.
See the entire definition of Alzheimer's disease

Amyloid: Any of a number of complex proteins that are deposited in tissues and that share selected laboratory features such as a change in the fluorescence intensity of certain aromatic dyes like Congo Red.
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Antidepressant: Anything, and especially a drug, used to prevent or treat depression.
See the entire definition of Antidepressant

Antioxidant: Any substance that reduces oxidative damage (damage due to oxygen) such as that caused by free radicals. Free radicals are highly reactive chemicals that attack molecules by capturing electrons and thus modifying chemical structures.
See the entire definition of Antioxidant

Antipsychotic: A medication (or another measure) that is believed to be effective in the treatment of psychosis. For example, aripiprazole (Abilify) is an antipsychotic medication used to treat schizophrenia.

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

ApoE: Abbreviation for apolipoprotein E, a gene that codes for a protein component of lipoproteins (complexes of fat + protein) that are normal constituents of blood plasma -- namely, chylomicrons, HDL (high density lipoprotein), LDL (low density lipoprotein), and VLDL (very low density lipoprotein).
See the entire definition of ApoE

Apolipoprotein E: A type of lipoprotein (a protein connected to a fat). Apolipoprotein E is abbreviated ApoE and the gene that encodes it is known as APOE. APOE is located on chromosome 19 in band 19q13.2.
See the entire definition of Apolipoprotein E

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.

Assisted living: A type of long-term care facility for elderly or disabled people who are able to get around on their own but who may need help with some activities of daily living, or simply prefer the convenience of having their meals in a central cafeteria and having nursing staff on call.

Autopsy: A postmortem examination. Also called a necropsy.
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Behavior therapy: A treatment program that involves substituting desirable behavior responses for undesirable ones.

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Benign: Not cancer. Not malignant. A benign tumor does not invade surrounding tissue or spread to other parts of the body. A benign tumor may grow but it stays put (in the same place).
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Brain: That part of the central nervous system that is located within the cranium (skull). The brain functions as the primary receiver, organizer and distributor of information for the body. It has two (right and left) halves called "hemispheres."

Cerebrospinal fluid: CSF. A watery fluid, continuously produced and absorbed, which flows in the ventricles (cavities) within the brain and around the surface of the brain and spinal cord.
See the entire definition of Cerebrospinal fluid

Cholesterol: The most common type of steroid in the body, cholesterol has gotten something of a bad name. However, cholesterol is a critically important molecule.
See the entire definition of Cholesterol

Cognitive: Pertaining to cognition, the process of knowing and, more precisely, the process of being aware, knowing, thinking, learning and judging. The study of cognition touches on the fields of psychology, linguistics, computer science, neuroscience, mathematics, ethology and philosophy.
See the entire definition of Cognitive

Computed tomography: An x-ray procedure that uses the help of a computer to produce a detailed picture of a cross section of the body. Also called a CT scan or CAT scan.

Constipation: Infrequent (and frequently incomplete) bowel movements. The opposite of diarrhea, constipation is commonly caused by irritable bowel syndrome, diverticulosis, and medications (constipation can paradoxically be caused by overuse of laxatives). Colon cancer can narrow the colon and thereby cause constipation. The large bowel (colon) can be visualized by barium enema x-rays, sigmoidoscopy, and colonoscopy. Barring a condition such as cancer, high-fiber diets can frequently relieve the constipation.

CT scan: Computerized tomography scan. Pictures of structures within the body created by a computer that takes the data from multiple X-ray images and turns them into pictures on a screen. CT stands for computerized tomography.
See the entire definition of CT scan

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.
See the entire definition of Cure

Dementia: Significant loss of intellectual abilities such as memory capacity, severe enough to interfere with social or occupational functioning.
See the entire definition of Dementia

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

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.
See the entire definition of Diagnosis

EEG: Electroencephalogram, e technique for studying the electrical current within the brain. Electrodes are attached to the scalp. Wires attach these electrodes to a machine which records the electrical impulses. The results are either printed out or displayed on a computer screen. Electroencephalogram is abbreviated EEG.
See the entire definition of EEG

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.
See the entire definition of Enzyme

Eskalith: See: Lithium.

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Estrogen: Estrogen is a female hormone produced by the ovaries. Estrogen deficiency can lead to osteoporosis.
See the entire definition of Estrogen

Familial: A condition that is tends to occur more often in family members than expected by chance alone. A familial disease may be genetic (such as cystic fibrosis) or environmental (such as tuberculosis).

Family history: The family structure and relationships within the family, including information about diseases in family members.
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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.
See the entire definition of FDA

Food and Drug Administration: The FDA, an agency within the U.S. Public Health Service, which is a part of the Department of Health and Human Services.
See the entire definition of Food and Drug Administration

Gene: The basic biological unit of heredity. A segment of deoxyribonucleic acid (DNA) needed to contribute to a function.
See the entire definition of Gene

Genes: The basic biological units of heredity. Segments of deoxyribonucleic acid (DNA) needed to contribute to a function.
See the entire definition of Genes

Genetic: Having to do with genes and genetic information.

Genetic testing: Tests done for clinical genetic purposes. Genetic tests may be done for diverse purposes pertaining to clinical genetics, including the diagnosis of genetic disease in children and adults; the identification of future disease risks; the prediction of drug responses; and the detection of risks of disease to future children.

Geriatrics: The branch of medicine concerned with the diagnosis, treatment and prevention of disease in older people and the problems specific to aging.
See the entire definition of Geriatrics

Glutamate: A form of glutamic acid. See: Glutamic acid.

Hormone: A chemical substance produced in the body that controls and regulates the activity of certain cells or organs.
See the entire definition of Hormone

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.
See the entire definition of Inflammation

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

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.
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Lithobid: See: Lithium.

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.


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Long-term memory: A system for permanently storing, managing, and retrieving information for later use. Items of information stored as long-term memory may be available for a lifetime.
See the entire definition of Long-term memory

Lumbar: Referring to the 5 lumbar vertebrae which are situated below the thoracic vertebrae and above the sacral vertebrae in the spinal column. The 5 lumbar vertebrae are represented by the symbols L1 through L5. There are correspondingly 5 lumbar nerves.

Lumbar puncture: A lumbar puncture or "LP" is a procedure whereby spinal fluid is removed from the spinal canal for the purpose of diagnostic testing. It is particularly helpful in the diagnosis of inflammatory diseases of the central nervous system, especially infections, such as meningitis. It can also provide clues to the diagnosis of stroke, spinal cord tumor and cancer in the central nervous system.
See the entire definition of Lumbar puncture

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.

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.

Memory: 1. The ability to recover information about past events or knowledge. 2. The process of recovering information about past events or knowledge. 3. Cognitive reconstruction. The brain engages in a remarkable reshuffling process in an attempt to extract what is general and what is particular about each passing moment.
See the entire definition of Memory

Menopause: The time in a woman's life when menstrual periods permanently stop; it is also called the "change of life." Menopause is the opposite of the menarche.
See the entire definition of Menopause

Mild cognitive impairment: Abbreviated MCI. A brain disorder in which thinking abilities are mildly impaired. Individuals with mild cognitive impairment are able to function in everyday activities but have difficulty with memory -- trouble remembering the names of people they met recently, remembering the flow of a conversation, and a tendency to misplace things. The individual may be aware of these difficulties and compensate with increased reliance on notes and calendars. The diagnosis of MCI relies on the fact that the individual is able to perform all their usual activities successfully, without more assistance from others than they previously needed. In this regard, MCI is different from dementia. In dementia, memory loss has progressed to such a point that normal independent function is impossible and the individual can no longer successfully manage their finances or provide for their own basic needs. Most (but not all) patients with MCI develop a progressive decline in their thinking abilities over time, and Alzheimer's disease is usually the underlying cause.

MRI: Abbreviation and nickname for magnetic resonance imaging. For more information, see: Magnetic Resonance Imaging; Paul C. Lauterbur; Peter Mansfield.

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.

Neurological: Having to do with the nerves or the nervous system.

Neurology: The medical specialty concerned with the diagnosis and treatment of disorders of the nervous system -- the brain, the spinal cord, and the nerves.
See the entire definition of Neurology

Neuropsychologist: A psychologist who has completed special training in the neurobiological causes of brain disorders, and who specializes in diagnosing and treating these illnesses using a predominantly medical (as opposed to psychoanalytical) approach.

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Neurotransmitter: A chemical that is released from a nerve cell which thereby transmits an impulse from a nerve cell to another nerve, muscle, organ, or other tissue. A neurotransmitter is a messenger of neurologic information from one cell to another.

NINDS: Stands for the National Institute of Neurological Disorders and Stroke, one of the National Institutes of Health in the U.S., whose mission is to "support and conduct research and research training on the normal structure and function of the nervous system and on the causes, prevention, diagnosis, and treatment of more than 600 nervous system disorders including stroke, epilepsy, multiple sclerosis, Parkinson's disease, head and spinal cord injury, Alzheimer's disease, and brain tumors."

Nursing: 1) Profession concerned with the provision of services essential to the maintenance and restoration of health by attending the needs of sick persons. 2) Feeding a infant at the breast.

Pharmacy: A location where prescription drugs are sold. A pharmacy is, by law, constantly supervised by a licensed pharmacist.

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.

Progressive: Increasing in scope or severity. Advancing. Going forward. In medicine, a disease that is progressive is going from bad to worse.

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.
See the entire definition of Protein

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

Psychiatry: The medical specialty concerned with the prevention, diagnosis, and treatment of mental illness.
See the entire definition of Psychiatry

Public health: The approach to medicine that is concerned with the health of the community as a whole. Public health is community health. It has been said that: "Health care is vital to all of us some of the time, but public health is vital to all of us all of the time."
See the entire definition of Public health

Quality of life: An important consideration in medical care, quality of life refers to the patient's ability to enjoy normal life activities. Some medical treatments can seriously impair quality of life without providing appreciable benefit, while others greatly enhance quality of life.

Receptor: 1. In cell biology, a structure on the surface of a cell (or inside a cell) that selectively receives and binds a specific substance. There are many receptors. There is a receptor for (insulin; there is a receptor for low-density lipoproteins (LDL); etc. To take an example, the receptor for substance P, a molecule that acts as a messenger for the sensation of pain, is a unique harbor on the cell surface where substance P docks. Without this receptor, substance P cannot dock and cannot deliver its message of pain. Variant forms of nuclear hormone receptors mediate processes such as cholesterol metabolism and fatty acid production. Some hormone receptors are implicated in diseases such as diabetes and certain types of cancer. A receptor called PXR appears to jump-start the body's response to unfamiliar chemicals and may be involved in drug-drug interactions.
2. In neurology, a terminal of a sensory nerve that receives and responds to stimuli.

Referral: The recommendation of a medical or paramedical professional. If you get a referral to ophthalmology, for example, you are being sent to the eye doctor. In HMOs and other managed care schemes, a referral is usually necessary to see any practitioner or specialist other than your primary care physician (PCP), if you want the service to be covered. The referral is obtained from your PCP, who may require a telephone or office consultation first.
See the entire definition of Referral

Risk factor: Something that increases a person's chances of developing a disease.

Rule out: A term much used in medicine, meaning to eliminate or exclude something from consideration. The ACB (albumin cobalt binding) test helps rule out a heart attack in the differential diagnosis of severe chest pain.

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Saliva: a watery secretion in the mouth produced by the salivary glands that aids in the digestion of food. Saliva also serves to moisten and cleanse the mouth, including the tongue and teeth, and contains substances that can play a role in the prevention of infection. Saliva aids digestion by moistening food and contains enzymes that begin the digestion process. Also known as spit.

Scan: As a noun, the data or image obtained from the examination of organs or regions of the body by gathering information with a sensing device.
See the entire definition of Scan

Senile: 1. Pertaining to old age. 2. Pertaining to the physical decline associated with old age. 3. Pertaining to the mental decline once associated with old age but now known to be due to dementia, such as Alzheimer's disease or cerebral atherosclerosis. "The road to senility is paved with plaques." (Paul F. Wehrle, MD [1921-2004] pediatrician and vaccine researcher)
See the entire definition of Senile

SPECT: An acronym that stands for Single Photon Emission Computed Tomography, a nuclear medicine procedure in which a gamma camera rotates around the patient and takes pictures from many angles, which a computer then uses to form a tomographic (cross-sectional) image.
See the entire definition of SPECT

Spinal tap: Also known as a lumbar puncture or "LP", a spinal tap is a procedure whereby spinal fluid is removed from the spinal canal for the purpose of diagnostic testing. It is particularly helpful in the diagnosis of inflammatory diseases of the central nervous system, especially infections, such as meningitis. It can also provide clues to the diagnosis of stroke, spinal cord tumor and cancer in the central nervous system.
See the entire definition of Spinal Tap

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.
See the entire definition of Stress

Stroke: The sudden death of some brain cells due to a lack of oxygen when the blood flow to the brain is impaired by blockage or rupture of an artery to the brain. A stroke is also called a cerebrovascular accident or, for short, a CVA.
See the entire definition of Stroke

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

Tomography: The process for generating a tomogram, a two-dimensional image of a slice or section through a three-dimensional object. Tomography achieves this remarkable result by simply moving an x-ray source in one direction as the x-ray film is moved in the opposite direction during the exposure to sharpen structures in the focal plane, while structures in other planes appear blurred. The tomogram is the picture; the tomograph is the apparatus; and tomography is the process.
See the entire definition of Tomography

Vitamin E: Alpha-tocopherol, an antioxidant vitamin which binds oxygen free radicals that can cause tissue damage. Deficiency of vitamin E can lead to anemia. Vitamin E may play a possible role in preventing heart disease and cancer of the lung and prostate.
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Alzheimer's Disease

Alzheimer's Disease and Down syndrome Overview

Alzheimer's disease (AD) is the most common form of dementia. The disease is progressive, and the brain degenerates. Alzheimer's disease is strongly associated with old age. However, it should not be considered a normal part of aging.

Down syndrome (DS) is a genetic disorder (the chromosome abnormality is acquired at the time of conception) in which a person has extra genes because of extra chromosome 21 material. The syndrome causes delays and limitations in physical and intellectual development. The extra chromosome material can be inherited from either parent. Common characteristics of the syndrome include:

  • Low muscle tone
  • Flat face (low nasal bridge and small nose)
  • Eye openings that slant downward and inward

  • Single crease across the centre of the palm
  • Smaller than normal size
  • Delay of both physical and intellectual development

People wi...

Read the Alzheimer's Disease in Individuals With Down Syndrome article »


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