ALS Glossary

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A chemical in the brain that acts as a neurotransmitter.

action tremor

A tremor that increases when the hand is moving voluntarily. 

activities of daily living (ADLs)

Personal care activities necessary for everyday living, such as eating, bathing, grooming, dressing, and using the toilet; a term often used by healthcare professionals to assess the need and/or type of care a person may require. 

advance directives

Documents (such as a Living Will) completed and signed by a person who is legally competent to explain wishes for medical care should he or she become unable to make those decisions at a later time. 


A non-specific symptom of one or more physical, or psychological processes in which screaming, shouting, complaining, moaning, cursing, pacing, fidgeting or wandering pose risk or discomfort, become disruptive or unsafe or interfere with the delivery of care. 


A drug that increases neurotransmitter activity by directly stimulating the nerve cell receptors. 


No movement. 

ALS (amyotrophic lateral sclerosis) 

A chronic, progressive disease marked by gradual degeneration of the nerve cells in the central nervous system that control voluntary muscle movement. The disorder causes muscle weakness and atrophy; symptoms commonly appear in middle to late adulthood, with death in two to five years. The cause is unknown, and there is no known cure. Also called Lou Gehrig's Disease, or Motor Neuron Disease. Literally, amyotrophic lateral sclerosis means without muscle nourishment, side (of spinal cord) hardening. 

Alzheimer's Disease 

A form of degenerative brain disease resulting in progressive mental deterioration with disorientation, memory disturbance and confusion. Alzheimer's leads to progressive dementia, often accompanied by dysphasia and/or dyspraxia. The condition may also give rise ultimately to spastic weakness and paralysis of the limbs, epilepsy and other variable neurological signs. 

amino acid 

One of the 20 building blocks of protein. 


A defense protein that binds to foreign molecules to allow elimination of the foreign molecule. 


Substances that are capable of causing the production of antibodies. Antigens may or may not lead to an allergic reaction. 


A chemical compound or substance that inhibits oxidation. 

arteriogram (angiogram) 

An X-ray scan of arteries going to and through the brain. Patients who have arteriograms first are injected with a radiopaque dye. 


A method to analyze or quantify a substance in a sample. An assay is an analysis done to determine: 1. The presence of a substance and the amount of that substance. 2. The biological or pharmacological potency of a drug. 


Loss of balance.  


Slow, involuntary movements of the hands and feet.  


The progressive loss of muscle mass, or wasting, caused by reduction in the size or number of muscle cells. It is one of the later symptoms of ALS. 

autoimmune disease 

A disease in which the body produces an immunogenic (i.e., immune system) response to some constituent of its own tissue. In other words the immune system loses its ability to recognize some tissue or system within the body as "self" and targets and attacks it as if it were foreign. Autoimmune diseases can be classified into those in which predominantly one organ is affected (e.g., hemolytic anemia and anti-immune thyroiditis), and those in which the autoimmune disease process is diffused through many tissues (e.g., systemic lupus erythematosus). For example, multiple sclerosis is thought to be caused by T cells attacking the sheaths that surround the nerve fibers of the brain and spinal cord. This results in loss of coordination, weakness, and blurred vision. 


The long, hair-like extension of a nerve cell that carries a message to the next nerve cell. 

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basal ganglia 

Several large clusters of nerve cells, including the striatum and the substantia nigra, deep in the brain below the cerebral hemispheres. 


Type of growth factor 

Bell's palsy 

An unexplained episode of facial muscle weakness or paralysis that begins suddenly and steadily worsens. 


Determination of the potency or concentration of a compound by its effect upon animals, isolated tissues, or microorganisms, as compared with an analysis of its chemical or physical properties. 


The chemistry of biology; the application of the tools and concepts of chemistry to living systems. Biochemists study the structures and physical properties of biological molecules. 


The process of developing tools and processes to quantify and collect data to study biological systems logically. 

blink rate 

The number of times per minute that the eyelid automatically closes -- normally 10 to 30 per minute. 

blood-brain barrier (BBB) 

A protective barrier formed by the blood vessels and glia of the brain. It prevents some substances in the blood from entering brain tissue. 


Slowness of movement. 


Slowness of thought processes. 

brain attack 

Another term for stroke. 

brisk reflex 

A condition that describes the deterioration of the upper motor nerve cells (neurons). 


Bulbar ALS is the type in which onset symptoms are in the facial muscles, speech and swallowing. 

bulbar muscles 

The muscles that control the speech, chewing and swallowing. 

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A cell marker on bone marrow derived cells 

central nervous system (CNS) 

The brain and spinal cord combined. 


The portion of the brain in the back of the head between the cerebrum and the brain stem. It is responsible for the coordination of movement and balance. 

cerebral embolism 

A situation in which a wandering clot (embolus) or some other particle lodges in a blood vessel in the brain. 

cerebral hemorrhage 

A type of stroke occurs when a defective artery in the brain bursts, flooding the surrounding tissue with blood. 

cerebral thrombosis 

The most common type of brain attack, it occurs when a blood clot (thrombus) forms and blocks blood flow in an artery bringing blood to part of the brain. 

cerebro-spinal fluid analysis (spinal tap) 

A procedure used to isolate cerebrospinal fluid for evaluation or diagnosis of disease. 

cerebro-spinal fluid analysis (spinal tap) 

A procedure used to isolate cerebrospinal fluid for evaluation or diagnosis of disease. 


The two largest, most complex and most developed lobes of the brain. Initiation and coordination of all voluntary movement take place within the cerebrum. The basal ganglia are located within the cerebrum. 


Rapid, jerky, dance-like movement of the body. 


A visible carrier of the genetic information. 


Marked by long duration or frequent recurrence. 

classical ALS 

A progressive neurological disease characterized by a deterioration of upper and lower motor nerve cells (neurons). This type of ALS affects more than two-thirds of all people with ALS. 


A drug used to deplete macrophages. 

CNTF (eiliary neurotrophic factor) 

A type of growth factor 

computed tomography (CT or CAT scan) 

A non-invasive X-ray procedure that takes cross-sectional images of the brain or other internal organs. It detects abnormalities that may not show up on an ordinary x-ray. 

cord blood 

Blood taken from the umbilical cord at the time of birth. It is rich in a variety of stem cells. For further information see 


The outer layer of the cerebrum, densely packed with nerve cells. 

corticospinal tract 

The bundle of nerves that reach from the motor area of the brain (see cortex) to the spinal cord, connecting to the nerves that go out to control the muscles. 


A gene involved in learning and memory. It appears to be the master switch that activates a number of growth factors and potentially some anti-apoptotic genes. Recent studies suggest CREB is neuroprotective. 


A surgical procedure in which a supercooled probe is inserted into a part of the brain called the thalamus in order to stop tremors. 


See cerebrospinal fluid. 


Cell marker on the surface of some immune cells. 

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A condition in which the patient has lost touch with reality and experiences hallucinations and misperceptions. 


Not a disease itself, but group of symptoms that is characterized by a decline in intellectual functioning that is severe enough to interfere with the ability to perform routine activities. 


Extensions from the neuron cell body that take information to the cell body. A single nerve may possess many dendrites. 


One of two types of molecules that encode genetic information 

dopa decarboxylase 

An enzyme present in the body that converts levodopa to dopamine. 


A chemical substance, a neurotransmitter, found in the brain that regulates movement, balance, and walking. 


A protein in nerve cells that helps move materials inside the cells 


Impaired speech and language due to weakness or stiffness in the muscles used for speaking. 


An involuntary movement including athetosis and chorea. 


Difficulty in swallowing. 


A slow movement or extended spasm in a group of muscles. 


A protein, a chemical substance made by muscle fibers. 

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electrodiagnostic tests 

Studies including electromyography (EMG) and nerve conduction velocity ( NCV), that evaluate and diagnose disorders of the muscles and motor neurons. Electrodes are inserted into the muscle, or placed on the skin overlying a muscle or muscle group, and electrical activity and muscle response are recorded. 

electroencephalogram (EEG) 

A method of recording the brain's continuous electrical activity by means of electrodes attached to the scalp. 


A "wandering" blood clot. 

embryonic stem cells 

Embryonic stem cells are the "blank slates" of an organism, capable of developing into all types of tissue in the body. Scientists have long been interested in the therapeutic potential of embryonic stem cells, which may be used someday to create new tissues for organ transplants and replacements for cells destroyed by diseases like diabetes or trauma like spinal cord injuries. 


An infection of the brain. 


A protein that acts as a catalyst in mediating and speeding a specific chemical reaction. 


A brain disorder involving recurrent seizures; may also be called a seizure disorder. 


A feeling of well-being or elation; may be drug related. 

evoked potentials 

A procedure to record the brain's electrical response to visual, auditory and sensory stimuli. 


Exciting neurons which can over time lead to neuronal death. 

exertional dyspnea 

A condition characterized by shortness of breath during physical activity. 

extensor muscle 

Any muscle that causes the straightening of a limb or other part. 

extrapyramidal system (EPS) 

The nerve cells, nerve tracts and pathways that connect the cerebral cortex, basal ganglia, thalamus, cerebellum, reticular formation, and spinal neurons. The EPS helps regulate reflex movements such as balance and walking. 

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familial ALS 

A progressive neurological disease that affects more than one member of the same family. This type of ALS accounts for a very small number of people with ALS in the United States (5 to 10 percent). 


Small, involuntary, irregular, visible contractions of individual muscle fibers. Often seen in the legs, arms and shoulders of PALS. This is often described by people with ALS as "persistent rolling beneath the skin." 


U.S. Food and Drug Administration, the branch of federal government which approves new drugs for sale. 

FDA 2000 

FDA 2000 project is a library of FDA approved compounds based on assay studies completed by Steve Gullans at Harvard. 


Walking with a series of quick, small, shuffling steps as if hurrying forward to keep balance. 

flaccid muscles (also hypotonicity) 

A condition characterized by a decrease or loss of normal muscle tone due to the deterioration of the lower motor nerve cells. 

flexor muscle 

Any muscle that causes the bending of a limb or other body part. 

formulation chemistry 

Formulation is a process by which a compound is prepared in a suitable form for administration to animals or human being depending on the dose, route and target tissue. 

free radicals 

Chemicals that are highly reactive and can oxidize other molecules (i.e. Superoxide). 

functional genomics 

Functional genomics is the area of genetics that focuses on determining the function of genetic information present in a cell or its ?genome function". 

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A cluster of nerve cell bodies. 

GDNF (glial derived neurotrophic factor) 

GDNF is a naturally occurring growth factor that proved capable of protecting and promoting the survival of motor neurons in animal studies. A growth factor is a growth inducing protein found in the human body. There was a growing interest in these naturally occurring proteins that have a supportive, reparative or protective role for motor neurons in animals. 

Gehrig, Lou 

(1903-1941), American professional baseball player, also known as the Iron Horse because he established a record for the most consecutive games played by a professional baseball player, appearing in 2130 games from 1925 to 1939. From 1923 until 1939 he played first base for the New York Yankees of the American League. Gehrig was twice voted the league's most valuable player (MVP). Stricken with the spinal disease ALS, which later became known as Lou Gehrig's disease, he retired from baseball in 1939. 


Genes are the basic biological units of heredity. They are composed of DNA. 

gene chip 

Gene chips are a way of automating experiments that previously could only be done one at a time. They are a picture of what the RNA looks like at one particular moment. Thousands of DNA pieces in genes are spotted on a small surface enabling us to look at changes in gene expression profile of thousands of genes in one experiment. By comparing tissue from ALS patients with tissue from controls we can discover which genes vary their expression level in the disease. 


All of the genetic information; the entire genetic complement; all of the hereditary material possessed by an organism. 


Glutamate is one of the most common amino acids found in nature. It is the main component of many proteins, and is present in most tissues. Glutamate is also produced in the body and plays an essential role in human metabolism. It is a primary excitatory neurotransmitter in the human CNS. L-glutamate is present at a majority of synapses. Over-stimulation of these same receptors is thought to trigger the neuronal damage associated with a wide variety of neurological insults and diseases, including amyotrophic lateral sclerosis (ALS), lathyrisms, and Alzheimer's disease. 

glutamate toxicity 

Toxicity resulting from excess glutamated synapse. 

gray matter 

The darker-colored tissues of the central nervous system. In the brain, the gray matter includes the cerebral cortex, the thalamus, the basal ganglia, and the outer layers of the cerebellum. 

growth factor 

A naturally occurring protein chemical that stimulates cell division differentiation and proliferation. It is produced by normal cells during embryonic development, tissue growth and wound healing. 

Guillain-Barre syndrome 

A disorder in which the body's immune system attacks part of the nervous system. 

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Includes tension (muscular contraction), vascular (migraine), and cluster headaches not caused by other underlying medical conditions. 


Includes headaches that result from other medical conditions. These may also be referred to as traction headaches or inflammatory headaches. 

hydrogen peroxide assay 

This assay is used to identify neuroprotective changes that can shield neurons from Hydrogen Peroxide injury. 


Excessive response of muscle reflexes when a normal stimulus is applied. 


Weak or absent muscle response when a normal stimulus is applied. 

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IgG (Intrathecal Gamma Globulin) 

A class of antibody. 

IL3 (interleukin-3) 

Small proteins released by cells that play a role in bone marrow cell proliferation and differentiation. 


Free from acquiring a certain infectious disease; resistant to an infectious disease. 

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. 


The study of all aspects of the immune system including its structure and function, disorders of the immune system, blood banking, immunization and organ transplantation. 


Prevention or interference with the development of an immunologic response; may reflect natural immunologic unresponsiveness (tolerance); may be artificially induced by chemical, biological, or physical agents, or may be caused by disease. 


The occurrence of new cases of a condition. The incidence rate describes the frequency with which cases are identified. Incidence is commonly measured in new cases per 1,000 (or 100,000) of population at risk, per year. The incidence of ALS typically varies between 1 and 4 diagnoses per 100,000 of populations per year in Western nations. 


Involuntary voiding of the bladder or bowel. 


The nonspecific immune response that occurs in reaction to any type of bodily injury. It is a stereotyped response that is identical whether the injurious agent is a pathogenic organism, foreign body, ischemia, physical trauma, ionizing radiation, electrical energy or extremes of temperature. The reactions produced during inflammation and repair may be harmful (i.e. hypersensitivity reactions, the processes that lead to rheumatoid arthritis, and possibly microglial over-activation in ALS). 

inflammatory disease 

Diseases that are characterized by activation of the immune system to abnormal levels that lead to disease. 


Injection into the innermost membrane surrounding the central nervous system. Usually done by lumbar puncture. 

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The smallest unit of a substance that can exist alone and retain the character of that substance. 

monoamine oxidase (MAO) 

An enzyme that breaks down dopamine. MAO comes in two forms: A and B. In Parkinson's disease, it is beneficial to block the activity of MAO B. 

motor neuron 

A neuron that conveys impulses initiating muscle contraction or glandular secretion. 

motor neuron disease (MND) 

A group of disorders in which motor nerve cells (neurons) in the spinal cord and brain stem deteriorate and die. ALS is the most common motor neuron disease. 

multiple sclerosis (MS) 

A chronic degenerative disease of the central nervous system in which gradual destruction of myelin occurs in patches throughout the brain or spinal cord (or both), interfering with the nerve pathways and causing muscular weakness, loss of coordination and speech and visual disturbances. It occurs chiefly in young adults and is thought to be a defect in the immune system that may be of genetic or viral origin. 


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." 

muscle atrophy 

Loss of muscle fiber volume characterized by a visible decrease in muscle size. This occurs because muscles no longer receive impulses or signals from nerve cells. 

muscle cramps, unexpected 

Involuntary, painful shortening of muscles. Usually, a knotting of the muscles is visible. 

muscle weakness 

Loss of muscle strength with increased fatigue, loss of coordination, difficulty with motor skills and lack of ability to carry out certain other skills. 

muscular dystrophy 

The name given to a group of diseases that are, for the most part, genetically determined and which cause gradual wasting of muscle with accompanying weakness and deformity. 


A permanent change, a structural alteration, in the DNA or RNA. Mutations can be caused by many factors including environmental insults such as radiation and mutagenic chemicals. Mutations are sometimes attributed to random chance events. 


A procedure that uses dye injected into the spinal canal to make the structure clearly visible on x-rays. 


Jerking, involuntary movements of the arms and legs. May occur normally during sleep. 

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

nervous system 

The system of cells, tissues and organs that regulates the body's responses to internal and external stimuli. In vertebrae it consists of the brain, spinal cord, nerves, ganglia and parts of the receptor and effector organs. 


In the microglial theory of ALS, the inflammatory immunological response to CNS injury causes damage in ALS. If this theory is correct, it could be said that ALS is a neuroimmune disease. 


A physician who specializes in the nervous system and its disorders. 


The medical science that deals with the nervous system and disorders affecting it. 


Of, relating to, or affecting both nerves and muscles. 


Neurons are the nerve cells which make up the central nervous system. They consist of a nucleus, a single axon which conveys electrical signals to other neurons and a host of dendrites which deliver incoming signals. 

neuronal receptors 

Neurons use chemical signaling mechanisms to communicate with one another. These impulses are transmitted at specialized junctions called synapses. The sending or signaling neuron triggers the release of neurotransmitters (or chemicals) into the synaptic cleft. From there the transmitters bind to receptors on the post synaptic or receiving neuronal cell. These receptors are the gate keepers of neuronal cells and they open and close to send or receive chemicals that signals which direct the actions and reactions of the cell. Chemical synapses can be excitatory or inhibitory. In an inhibitory synapse, binding of the neurotransmitter causes a change in ion permeability that tends to block the generation of opening of the plasma membrane in the receiving cell. For most cases, the binding of an inhibitory neurotransmitter causes a hyper-polarization in closing of the postsynaptic or receiving membrane. 


If an agent provides protection to any part of the body's nervous system, it is said to provide neuroprotection. 


If an agent provides growth and regeneration to any part of the nervous system, it is said to be neuroregenerative. 


The scientific disciplines concerned with the development, structure, function, chemistry, pharmacology, clinical assessments and pathology of the nervous system. 


A procedure that uses ultra high frequency sound waves to reveal patterns of blood flow. It is commonly used to help confirm stroke. 


Chemical substances that carry impulses from one nerve cell to another; found in the space (synapse) that separates the transmitting neuron's terminal (axon) from the receiving neuron's terminal (dendrite). 


Of or referring to the substantia nigra. 


A neurotransmitter found mainly in areas of the brain involved in governing autonomic nervous system activity, especially blood pressure and heart rate. 

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on-off effect; on-off phenomenon 

A change in the patient's condition, with sometimes rapid fluctuations between uncontrolled movements and normal movement, usually occurring after long-term use of levodopa and probably caused by changes in the ability to respond to this drug. 


The time of appearance of the first symptoms of a condition, prior to seeking diagnosis. 

orthostatic hypotension 

A large decrease in blood pressure upon standing; may result in fainting. 

oxidative stress 

Accumulation of destructive molecules called free radicals can lead to motor neuron death. Free radicals damage components of the cells' membranes, proteins or genetic material by "oxidizing" them - the same chemical reaction that causes iron to rust. Some patients with familial ALS have mutations in the gene for superoxide dismutase type 1 (SOD1). SOD1 normally breaks down free radicals, but mutant SOD1 is unable to perform this function. These free radicals may be generated when the enzyme superoxide dismutase malfunctions (either because of a genetic mutation or because of the chemical environment of the nerve cells), or they may be generated as a result of glutamate excitotoxicity, or for some other reason. Many ALS patients take over the counter antioxidants such as Coenzyme Z Q10 and Vitamin E in an effort to neutralize free radicals. 

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A surgical procedure in which a part of the brain called the globus pallidus is lesioned in order to improve symptoms of tremor, rigidity, and bradykinesia. 


Person with ALS. 


Paralysis of a muscle or group of muscles. 

Parkinson's Disease 

The most common form of Parkinson's is slowly progressing and degenerative, usually associated with the following symptoms. All of these result from the loss of dopamine-producing brain cells: tremor or trembling of the arms, jaw, legs, and face; stiffness or rigidity of the limbs and trunk; bradykinesia ? slowness of movement; postural instability, or impaired balance and coordination. 


The name given to a group of disorders with similar features -- four primary symptoms (tremor, rigidity, postural instability, and bradykinesia) that are the result of the loss of dopamine-producing brain cells. 

PEG tube 

Percutaneous endoscopic gastrostomy tube - a tube placed directly into the stomach through the abdominal wall to provide another way to receive nourishment and liquids. 


Wavelike contractions that move food through the digestive tract. 


A cell that can engulf particles such as bacteria, other microorganisms, aged red blood cells, foreign matter, etc. 


The study of the metabolism and action of drugs with particular emphasis on the time required for absorption, duration of action, distribution in the body and method excretion. 

pharmacological properties 

A drug's half life, molecular weight, permeability, chemical structure and methods of action through the pathways it affects. 


The study of drugs and their origin, nature, properties and effects upon living organisms. 


The expression of the genes present in an individual. This may be directly observable (eye color) or apparent only with specific tests (blood type). Some phenotypes such as the blood groups are completely determined by heredity, while others are readily altered by environmental agents. 


A self-replicating (autonomous) circle of DNA distinct from the chromosomal genome of bacteria. A plasmid contains genes normally not essential for cell growth or survival. Some plasmids can integrate into the host genome, be artificially constructed in the laboratory and serve as vectors (carriers) in cloning. 

pluripotent stem cells 

Human pluripotent stem cells are a unique scientific and medical resource. They can develop into most of the specialized cells and tissues of the body, such as muscle cells, nerve cells, liver cells, and blood cells, and they are self-renewing, making them readily available for research, and potentially, for treatment purposes. Scientists derived these unique cells from human embryos and from fetal tissue 

positron emission tomography (PET) scan 

A computer-based imaging technique that provides a picture of the brain's activity rather than its structure. The technique detects levels of injected glucose labeled with a radioactive tracer. 

primary lateral sclerosis (PLS) 

A progressive neurological disease in which the upper motor nerve cells deteriorate. If the lower motor neurons are not affected within two years, the disease usually remains a purely upper motor disease. 

progressive bulbar palsy (PBP) 

A condition that begins with difficulties in speaking, chewing and swallowing due to lower motor nerve cell (neuron) deterioration. This disorder affects about 25 percent of all people with ALS. 

progressive muscular atrophy (PMA) 

A progressive neurological disease in which the lower motor nerve cells (neurons) deteriorate.  


Proteins are large molecules required for the structure, function, and regulation of the body's cells, tissues, and organs. Each protein has unique functions. Proteins are essential components of muscles, skin, bones and the body as a whole. Protein is also one of the three types of nutrients used as energy sources by the body. 


The study and identification of the proteins produced by the genetic instructions carried by a cell. 


A precise and detailed plan for the study of a biomedical problem or for a regimen of an experimental therapy. 

pseudobulbar palsy 

A condition characterized by difficulties with speech, chewing and swallowing. These symptoms resemble those of bulbar palsy, but this condition is also characterized by spontaneous or unmotivated crying and laughing. 

pyramidal pathway 

A collection of nerve tracts that travel from the cerebral cortex through the pyramid of the medulla oblongata in the brainstem to the spinal cord. Within the pyramid of the medulla, fibers cross from one side of the brain to the opposite side of the spinal cord; the pyramidal pathway is intact in Parkinson's disease. 

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Rays of energy. The term "radiation" also refers to the use of energy waves to diagnose or to treat disease. 


A prescription medicine approved by the Federal Drug Administration (FDA) to treat people with ALS. Also known as edaravone. Radicava requires a prescription from your health care professional.

range of motion 

The extent that a joint will move from full extension to full flexion.  

resting tremor 

A tremor, in a limb, that increases when the limb is at rest.  


The tendency to step backwards if bumped from the front or upon initiating walking, usually seen in patients who tend to lean backwards because of problems with balance. 


Increased resistance to the passive movement of a limb. 


The first FDA-approved drug available to treat ALS. It inhibits glutamate release, and prolongs life approximately three months. Riluzole is the generic name of Rilutek.  


A long-chain, usually single-stranded. The primary function of RNA is protein synthesis within a cell. However, RNA is involved in various ways in the processes of expression and repression of hereditary information. The three main functionally distinct varieties of RNA molecules are: (1) messenger RNA (mRNA) which is involved in the transmission of DNA information, (2) ribosomal RNA (rRNA) which makes up the physical machinery of the synthetic process, and (3) transfer RNA (tRNA) which also constitutes another functional part of the machinery of protein synthesis. 

routes of administration 

The different ways in which a drug can be delivered (i.e. intravenously, intrathecally, intramuscularly, orally). 

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A hardening within the nervous system, especially of the brain and spinal cord, resulting from degeneration of nervous elements such as the myelin sheath. 


An important neurochemical whose effects upon the human brain include mood elevation. Production of serotonin in the brain is increased by ingestion of the amino acid tryptophan (a chemical precursor to serotonin) and the pharmaceutical anti-depressant Prozac (trademarked product of Eli Lilly & Company). In 1997, Marianne Regard and Theodor Landis discovered that humans afflicted with hemorrhagic lesions in the brain (cause of abnormal serotonin activation/production) often became "passionate culinary afficionados." 



side effect 

An action or effect of a drug other than that desired. Commonly it is an undesirable effect such as nausea, headache, insomnia, acute toxic reaction or drug interaction. 


See superoxide dismutase. 

SOD assay 

Bob Brown at Massachusetts General Hospital is completing this project. The SOD assay uses the mutant SOD gene and a series of drugs that are presented to the SOD cells that attempt to prevent the cells' death. He has screened approximately 400 drugs and has had 14 hits thus far. This assay testing is still in progress. 


A chemical necessary for communication between nerve cells. 


A condition in which a muscle or group of muscles involuntarily contract.  

spinal cord 

Part of the central nervous system extending from the base of the skull through the vertebrae of the spinal column. It is continuous with the brain stem, and like the brain it is encased in a triple sheath of membranes. Thirty-one pairs of spinal nerves arise from the sides of the spinal cord. The spinal cord carries information from the body's nerves to the brain and signals from the brain to the body. 

spinal muscular atrophy (SMA) 

A hereditary neurological disease in which only the lower motor nerve cells are affected. 

stem cell transplant 

Transplantation of stem cells from various sources has provided improvement in animal spinal neurodegenerative disease models such as stroke, epilepsy, Parkinson's and spinal cord injury. Human trials are promising, but not complete. 

stem cells 

Cells that can differentiate into many different cell types when subjected to the right biochemical signals. Stem cells are a promising new therapeutic approach to treating CNS disorder. The most versatile stem cells, called pluripotent stem cells, are present in the first days after an egg is fertilized by sperm. Researchers believe they can coax stem cells to become whatever tissues patients need. Stem cells come from embryos, bone marrow and umbilical chords. View the STEM CELL GLOSSARY to learn more 


Part of the basal ganglia, it is a large cluster of nerve cells, consisting of the caudate nucleus and the putamen, that controls movement, balance, and walking; the neurons of the striatum require dopamine to function. 


Also called a "brain attack" and happens when brain cells die because of inadequate blood flow. 20% of cases are a hemorrhage in the brain caused by a rupture or leakage from a blood vessel. 80% of cases are also know as a "schemic stroke", or the formation of a blood clot in a vessel supplying blood to the brain. 

subarachnoid hemorrhage 

A brain attack that occurs when a blood vessel on the surface of the brain ruptures and bleeds into the space between the brain and the skull (but not into the brain itself). 

substantia nigra 

A small cluster of black-pigmented nerve cells in the brain that produce dopamine. Messages from the substantia nigra are transmitted to the striatum. 

superoxide dismutase 

An enzyme that destroys superoxide. One form of the enzyme contains manganese and another contains zinc. Superoxide is a highly reactive form of oxygen. For ALS, 20% of the total population of patients have mutations in the gene for copper/zinc superoxide dismutase type SOD1. SOD1 normally breaks down free radicals, but mutant SOD1 is unable to perform this function. For more information, see  

sustention (postural) tremor 

A limb tremor that increases when the limb is stretched. 


A tiny gap between the ends of nerve fibers across which nerve impulses pass from one neuron to another; at the synapse, an impulse causes the release of a neurotransmitter, which diffuses across the gap and triggers an electrical impulse in the next neuron. 

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therapeutic index 

A general way of measuring an effective dose of a drug and its toxicity. 


A blood clot 


The extent, quality or degree of being poisonous. 


Division of medical and biological science concerned with drugs. Scientists study their chemistry and pharmacological actions, and establish antidotes and treatment of toxic manifestations, prevention of poisoning, and methods for controlling exposure to harmful substances. 


A poisonous substance of animal or plant origin. 


An organism whose sperm or egg contain genetic material originally derived from an organism other than the parents or in addition to the parental genetic material. 


Medical or surgical management of a patient. Any specific procedure used for the cure of or the amelioration of a disease or pathological condition. 


A rhythmical shaking of a limb, head, mouth, tongue or other part of the body that is involuntary in nature. 

Trophic Factor 

One of a class of proteins that help keep cells healthy. 


The amino acid from which dopamine is made.  

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upper motor neurons 

Nerve cells (motor neurons) originating in the brain's motor cortex and running through the spinal cord. 

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Any substance, bearing antigens on its surface, that causes activation of an animal?s immune system without causing actual disease. The animal's immune system components (e.g. antibodies) are then prepared to quickly vanquish those particular pathogens when they later enter the body. 


The agent used (by researchers) to carry new genes into cells. Plasmids currently are the vectors of choice, though viruses and other bacteria are increasingly being used for this purpose. 

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white matter 

Nerve tissue that is paler in color than gray matter because it contains nerve fibers with large amounts of insulating material (myelin). The white matter does not contain nerve cells. In the brain, the white matter lies within the gray layer of the cerebral cortex. 


Wobbler is a neurodegenerative disease model that arose in a laboratory mouse by chance. As it has a very valuable phenotype that mimics ALS and other motor neuron diseases, it was maintained by breeding. As it was a mutation that arose spontaneously, we currently have no information on where in the mouse genome the ALS-producing mutation is present. Currently investigators are trying to identify the location of the mutation in the mouse. Various therapies have been tested in this model and most of the drugs that worked in the model also worked in the genetic ALS model (SOD1G93A). Thus it appears that this is a good model for screening drugs.

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A drug that extended the life of ALS mice by 21 percent. Studies concluded that although zVAD-FMK helps mice, the drug is too toxic for human use. It's a caspase (cell suicide) and protease (enzymes that cut proteins to shreds for recycling) inhibitor and ALS-TDF is now collaborating in the development of safer drugs that affect the same pathways. There are two new versions of zVAD-FMK that are now in formulation testing at the Foundation. 

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