Glossary of Terms

Adult Stem cells:

Cells which are found in human/animal tissue of a developed body, ie after birth. They are specialised to the tissue which they can be found in, and are capable of regeneration to replace specific cells for those that have died or are lost.

 

Akinesia:

Refers to the inability to move, or absence of the ability to move.

 

Alleles:

Forms of the same gene with small differences in their sequence of DNA bases. These small differences contribute to each person’s unique physical features.

 

ALS:

Amyotrophic Lateral Sclerosis (ALS) is a form of Motor Neurone Disease (MND) which is a progressive neurological disorder. The normal functioning of a neurone is affected, resulting in an inability to receives and sends messages from the body to the brain and back to the body. As motor neurones degenerate, they can no longer send impulses to the muscle fibres that normally result in muscle movement, which in turn leads to muscle weakness and wasting.

 

ALS-FRS:

This stands for ‘ALS functional rating scale’ and is a measure of a patients’ ability to carry out daily motor tasks such as climbing stairs.

 

ANG (Angiogenin) gene:

The ANG gene provides instructions for making a protein called angiogenin. This angiogenin protein promotes the formation of new blood vessels from pre-existing blood vessels through a process called angiogenesis.

 

Angiogenesis:

A process which enables angiogenin to stimulate the growth and division of endothelial cells, which line the inside surface of blood vessels, to form new blood vessels. Angiogenesis is important for restoring blood flow after an injury.

 

Ataxia:

Failure of muscular coordination, irregularity of muscular action – may lead to the loss of balance.

 

Atrophy:

Progressive wasting of muscle.

 

Axon:

Nerve fibers that are capable of rapidly conducting impulses away from the neurone cell body

 

Bulbar muscles:

Muscles in the head and neck that control speech, chewing and swallowing.

 

Bulbar symptoms:
Symptoms involving the impairment of speech and swallowing.

 

Central Nervous System (CNS):

The brain and spinal cord.

 

Cell:

A cell is the basic structural and functional unit of all organisms.

 

Clonus:

Involuntary muscle contractions which are usually rapid and rhythmic in nature. May occur sporadically or in response to a certain movement/reflex.

 

Chromosome:

found in the nucleus of a cell, which contains the genes. Chromosomes come in pairs, and a normal human cell contains 46 chromosomes.

 

C9orf72:

This is a gene that is mutated in some ALS patients and is the gene most commonly associated with familial ALS.

 

Dementia:

Acquired deterioration in cognitive abilities that impairs activities of daily living.

 

DNA:

A material found within the cell nucleus and is responsible for carrying genetic information. Each person has their own unique DNA.

 

DNA Bank:

A project funded by the MND Association that collects and stores samples of DNA from people with MND and their unaffected carers / family. The bank provides a great resource for investigation into the genetic causes of MND.

 

Dysarthria:

Impaired speech.

 

Dysphagia:

Impaired swallowing.

 

Dyspnoea:

Difficulty breathing.

 

ECAS:

This stands for ‘Edinburgh cognitive and behavioural ALS screen’ and it is a quick assessment which determines where a patient is succumbing to any cognitive impairment.

 

Efferent Nerve:

A nerve that carries impulses away from the central nervous system (CNS). An efferent nerve is the opposite of an afferent nerves that carries impulses toward the CNS.

 

EEG:

This stands for ‘electroencephalogram’ and is a non-invasive neurophysiological technique which capture cortical brain oscillations in real-time.

 

EMG:

Electromyography, or EMG, is a neurophysiological technique used to assess electrical activity of muscles. Muscular movement is elicited via electrical currents which are picked up by recording electrodes used in EMG. In MND, the electrical activity of the muscles or nerves is affected. Finding and describing these electrical properties in the muscle or nerve helps confirm a diagnosis.

 

Enzyme:

A protein that increase the rate of a chemical reaction in the body.

 

Fasciculations:

Small, involuntary, irregular and visible contractions of individual muscle fibres. Often seen in the legs, arms, shoulders and tongue.

 

Feeding tubes:

A feeding tube is a medical device used to provide nutrition to patients who cannot obtain adequate daily calorie intake by swallowing. Percutaneous endoscopic gastrostomy (PEG) tubes are most commonly used. Tubes are inserted while the person is sedated and is placed with the aid of an endoscope, to assist in guiding the placement of the tube through the wall of the stomach.

 

Frontotemporal dementia (FTD):

A disorder characterized by cognitive, behavioural, and sometimes motor abnormalities reflecting degeneration of the brain, anterior frontal and temporal regions, basal ganglia, and motor neurons.

 

Gene:

A gene is the basic physical and functional unit of heredity, consisting of a segment of DNA arranged in a linear manner along a chromosome. Genes carry out instructions to make molecules called proteins. Every person has two copies of each gene, one of which is inherited from each parent.

 

Genetic:

 having to do with information that is passed from parents to offspring through genes in sperm and egg cells.

 

Hyperreflexia:

Excessive response of muscle reflexes when a stimulus is applied.

 

Idiopathic:

Of unknown cause. Any disease that is of uncertain or unknown origin may be termed idiopathic.

 

Inherited:

Genetic; having to do with information that is passed from parents to offspring through genes in sperm and egg cells.

 

Lower motor neurone:

Located in the brain stem and spinal cord, they are responsible for carrying messages to the muscle fibres.

 

Major Gene:

A gene that is necessary and sufficient by itself to cause a condition.

 

Neurofibril:

Any of the long, thin, microscopic fibrils that run through the body of a neuron and extend into the axon and dendrites, giving the neuron support and shape.

 

Neurofilament:

Any of the long fine threads that make up a neurofibril.

 

Neurological:

Having to do with the nerves or nervous system.

 

Neurone:

The basic cellular unit of nervous tissue. Each neurone is composed of a body, an axon and dendrites. The function of a neurone is to act as a messenger for communication from the body to the brain and back to the body.

 

Neurofibril:

Any of the long, thin, microscopic fibrils that run through the body of a neuron and extend into the axon and dendrites, giving the neuron support and shape.

 

Neurotransmitter:

Any of the various chemical substances, such as acetylcholine, that transmit nerve impulses across a synapse.

 

Neurotrophic factors:

A family of protein which induce the survival of neurones.

 

NIPPV (Non-Invasive Positive Pressure Ventilation):

Can be used to alleviate symptoms of breathlessness when the respiratory muscles become weak. Works through a mask by providing extra air when you breathe in. Most people who use this equipment do so at night because breathing is shallower when you are asleep

 

Protein:

Fundamental components of all living cells and include many substances, such as enzymes, hormones and antibodies, that are necessary for the proper functioning of an organism. They are compounds containing an amino acid sequence of more than 100 amino acids, at least two of which are different, bound mostly through normal peptide links.

 

Peptides:

Compounds containing a sequence of 4-100 amino acid units, which are bound through at least one normal peptide link.

 

Ribonucleic acid (RNA):

A substance found in the cell nucleus which is responsible for regulating which genes are kept active. It serves as the intermediary between genes and the proteins that they code for.

 

 Riluzole:

This is currently the only approved treatment for ALS and has been seen to prolong life by 2-3 months.

  

SOD (Superoxide Dismutase):

An enzyme that inactivates excess free radicals, preventing them from damaging cell membranes. Mutations in the first SOD (SOD1) has been linked to familial forms of MND.

 

Synapse:

The gap across which a nerve impulse passes from an axon terminal to a neuron, a muscle cell, or a gland cell.

 

TMS:

This stands for ‘Transcranial magnetic stimulation’ and is a non-invasive neurophysiological technique used to investigate excitation-inhibition balance in the brain. 

 

Upper motor neurone:

Located in the brain, they send messages to the spine but are unable to leave the central nervous system.