Contact Us!


Glossary Terms

Special thanks to Dr. Steven Dealler for originally posting many of these terms on his site. Thanks also to Mary,  a CJD Voice member, for providing more terms.

Advisory Committee on Dangerous Pathogens

Agricultural Development and Advisory Service. This was a government organization that provided cheap veterinary and agricultural advice to farmers. The Thatcher Government decided that the farmers should pay higher prices and that it should be privatized if possible. As a result it was decreased in size dramatically.

The element that is able to transmit a disease. We are currently unsure what the absolute agent is for a TSE (such as CJD). Some arguments suggest that it is a virus (see Diringer) some that it is a virino (see Kimberlin or Narang) and many that it is a prion (see Bolton or Prusiner).

Alzheimer's Disease
A specific disease associated with the breakdown of nervous tissue in the brain, giving rise to a dementia in the patient. This seems to be one of the most common conditions of older people in the Western world.

A chemical that builds up inside tissue in an amorphous way.

The production of amyloid

The build up of amyloid to a degree that it causes damage to the tissues or action of those tissues in the body.

One of the brain cells that supports the nervous tissue.

The spread of astrocytes into damaged tissue.

Loss of coordination by an animal with neurological damage.

The inoculation of tissue into another animal in order to see if it is infective (if it is, the animal will develop disease). Multiple dilutions of the inoculum will, if the dilutions are enough, get to the point that not enough infection is present in the inoculum to cause disease. The lowest amount of inoculum that will still transmit the disease is said to contain one infective unit.

The appearance under the microscope of Congo red staining of amyloid.

Bovine spongiform encephalopathy

the DNA of the chromosome i.e. chromosomal DNA.

cerebellum n.
- the largest part of the hindbrain, bulging back behind the pons and the medulla oblongata and overhung by the occipital lobes of the cerebrum. Like the cerebrum, it has an outer gray cortex and a core of white matter. Three broad bands of nerve fibers - the inferior, middle, and superior

cerebellar peduncles
connect it to the medulla, the pons, and the midbrain, respectively. It has two hemispheres, one on each side of the central region (the vermis), and its surface is thrown into thin folds called folia. Within lie four pairs of nuclei.
The cerebellum is essential for the maintenance of muscle tone, balance, and the synchronization of activity in groups of muscles under voluntary control, converting muscular contractions into smooth coordinated movement. It does not, however, initiate movement and plays no part in the perception of conscious sensations or in intelligence. -cerebellar adj.

cerebellar ataxia n.
clumsiness of willed movements. The patient staggers when walking; he cannot pronounce words properly and has *nystagmus.

Cellular culture
The culture of individual cells in a test-tube. Some of these can be infected with a TSE agent and these cultures can then be used to see if a drug may work against the agent

Chronic wasting disease (of deer)
A disease found at Fort Worth Zoo only in deer and elk.

The build up of PrP in a crystal form in such a way as to induce the production of PrPsc from PrPc.

Clinicopathological correlations
The association between the damage that appears to the brain under the microscope and the damage that appears to have happened to the activity of the brain.

Central nervous system..

Congo red
A specific dye that is used to stain amyloid but has also been found to inhibit the build up of PrP in infected tissue in culture.

Material in histological sections that becomes stained by Congo red.

Creutzfeldt-Jakob Disease
A TSE that gives rise to a pre-senile dementia in human.

Cerebrospinal fluid

Central Veterinary Laboratory

dementia n.
a chronic or persistent disorder of the mental processes due to organic brain disease. It is marked by memory disorders, changes in personality, deterioration in personal care, impaired reasoning ability, and disorientation. Presenile dementia occurs in young or middle-aged people. The term is sometimes reserved for Alzheimer's disease and Pick's disease, but it is important to distinguish these conditions from those brain diseases for which curative treatment may be available.

Deoxyribonucleic acid. The chemical that carries the genome in the chromosome of animals, plants and some viruses.

Department of Health, UK

The extent to which a gene is expressed; dominant indicates that it is expressed a lot.

Downer cows
Cattle that show neurological problems (an American term)

dysarthia n.
a speech disorder in which the pronunciation is unclear although the linguistic content and meaning are normal.

dysphagia n.
condition in which the action of swallowing is either difficult to perform, painful (see odynophigia), or in which swallowed material seems to be held up in its passage to the stomach. It is caused by painful conditions of the mouth and throat, obstruction of the pharynx or esophagus by diseases of the wall or pressure from outside, or by abnormalities of muscular activity of the pharynx or esophagus.


The drawing of a mixture of proteins through a fine gel by an electric current. This separates the proteins so that they can be identified.

The changes in the numbers of cases of disease in relation to time and space.

A part of a gene.

Esophagitis n.
inflammation of the esophagus (gullet). Symptoms include heartburn, regurgitation of bitter fluid, and sometimes difficulty in swallowing. It may be caused by hernia, fungus infection or virus infection.

European Union.

Famillial Fatal Insomnia
A clinical disease found in humans that has been found to be a TSE and is due to a specific change found in the prion protein.

Freidreich's ataxia n.
an inherited disorder appearing first in adolescence. It has the features of cerebellar ataxia, together with spasticity of the limbs.

Frontal lobe n.
portion of the brain containing the motor cortex responsible for control of voluntary movement.

Feline spongiform encephalopathy

The total make-up of the genes for an infective agent (or any other life).

The types of the genes of an organism.

A familial TSE found in humans and associated with a specific change in the PrP gene.

A type of protein with a specific type of glycoprotein attached. i.e. two proteins would be of the same glycoform if they carried the same glycoprotein. This was important in that Dealler's hypothesis that the strain of prion disease depended on the glycan chain was shown to some degree by Collinge et al in 1996 and that this inferred that treatment was possible.

A protein that carries attached to it some chains of sugars (glycans). PrP carries two of these chains and it has been suggested that it is different chains that actually separate the strains of TSEs.

With a carbohydrate added.

Iatrogenic cases
These are the cases of CJD that appear as a result of medical activity inoculating the disease into the patient. e.g. growth hormone inoculations, corneal transplants, dura mater grafts and various surgical procedures.

a method of separating molecules using liquid chromatography

The removal of specific proteins onto a filter paper, and then testing the paper for the protein. This is a way of purifying and being sure of what is found.

The testing of sections of tissue for specific proteins by attaching them with specific antibodies, and then looking for the antibodies through the enzymes to which they were connected.

The testing of sections of tissue (or electron microscopy samples) by attaching antibodies to specific proteins in the tissue. The antibodies may have further labels attached to them and it is these that act as the labels.

As in immunohistochemistry but using a dye as the indicator.

Infective range
The range of animals that a disease can infect.

Infective Unit
This is the minimum amount needed to transmit a TSE from one animal to another of the SAME species.

Inversely related
One item affects another so that when one increases the other drops.

A disease found in the Fore tribe in New Guinea, and due to the eating of human infected tissue by members of a tribe. In general the women ate brain tissue rather than the men and so it was the women and children that died relatively rapidly of the disease.

Lateral (or horizontal) transmission
transmission of a disease from one animal to another except from the parent to the offspring. Generally this is the transmission between two animals alive at the same time and for one to be exposed to the agent from the other.

Ministry of agriculture fisheries and food in the UK.

Maternal transmission
The transmission of disease from the mother to the offspring (not necessarily before birth).

Meat and bone meal.

immune cells from inside the CNS

Murine models
models of disease, using mice as the animal being infected.

Myoclonic jerks n.
Occasional jerks which occur between seizures in patients with idiopathic *epilepsy

myoclonus n.
a sudden spasm of the muscles typically lifting and flexing the arms. Occasional myoclonic jerks occur between seizures in patients with idiopathic *epilepsy, and myoclonus is a major feature of some progressive neurological illnesses with extensive degeneration of brain cells. myoclonic adj.

The anatomy of the brain, spinal cord and peripheral nervous system.

Neurogenenic culture
The growth of nervous tissue in the test tube for the growth of the TSE agent in the tissue.

The production of new nervous tissue.

Nystagmoid jerks n.
Jerking movements which sometimes occur in normal people when tired and when there is an exaggerated movement of the eyes. They do not imply disease.

nystagmus n.
rapid involuntary movements of the eyes that may be from side to side, up and down, or rotatory. Nystagmus may be congenital and associated with poor sight; it also occurs in disorders of the part of the brain responsible for eye movements and their coordination and in disorders of the organ of balance in the ear or the associated parts of the brain. Optokinetic nystagmus occurs in normal people when they try to look at a succession of objects moving quickly across their line of sight. Jerking movements sometimes occur in normal people when tired and when there is an exaggerated movement of the eyes. These are called nystagmoid jerks and they do not imply disease.

odynophagia n.
a sensation of pain behind the sternum as food or fluid is swallowed; particularly, the burning sensation experienced by patients with *esophagitis when hot, spicy, or alcoholic liquid is swallowed.

Optokinetic nystagmus
n. rapid involuntary movements of the eyes that may be from side to side, up and down, or rotatory and occur in normal people when they try to look at a succession of objects moving quickly across their line of sight.

Over thirty months. See TMR.

polyacrylamide gel electrophoresis to separate molecules.

Inoculation into the body (not by mouth)

The inoculation of an infection into an animal and then harvesting the infective agent from the animal.

The production of damage (pathology) in a tissue.

Polymerase chain reaction. A method use to make multiple copies of DNA.

This generally refers to the ingestion or inoculation of material into an animal outside the central nervous system.

The effect made on the organism by the genes that it carries. Some genes (see genotype) may have no effect.

Pick's disease
n. a rare cause of dementia in middle-aged people. The damage is mainly in the *frontal and *temporal lobes of the brain, in contrast with the diffuse degeneration of *Alzheimer's disease.

The proteinaceous elements that may build up in brain tissue as a result of infection. They may, however, be found in other diseases apart from a TSE.

This is the way that prions may be thought to build up. i.e. by one PrPc joining onto the end of a PrPsc crystal.

The chemical element that changes due to enzymatic or physical pressure.

Prefrontal lobe
n. portion of the brain concerned with behavior, learning, judgment and personality.

Presenile dementia n.
dementia which occurs in young or middle-aged people. The term is sometimes reserved for Alzheimer's disease and Pick's disease.

This is the protein that makes up the infectious agent claimed by a large number of groups now to be the infectious particle that transmits the disease from one cell to another and from one animal to another. It is made from the normal protein PrPc (the c stands for chromosomal) that is produced in small quantities on many cells and especially the lymphoid and nervous tissue cells.

Prion rods
The microscopic rods that appear when prions, that have been broken up with proteinase K but then allowed to come back together into crystalline forms.

A chemical agent that causes the expression of a gene or the change in the way that it acts.

Protease K
This is the enzyme that breaks down proteins very powerfully...but the protein that is found in an infected cell is, for some reason not broken down by the enzyme.

The prion protein. It can exist in various forms. One is called PrPc and is the normal type of the protein that is found in a cell (i.e. chromosomal PrP). One is called PrPsc (or PrPscrapie) that is found in the infected cells. It may be called PrP-res, indicating that it is difficult to break down with proteinases. PrP27-30 is the name of the prion protein after it has been broken up by protease K.

Ribonucleic acid. Often found in viruses as the nucleic acid that caries the genome of the agent.

Romberg's sign n.
evidence of a sensory disorder affecting those nerves that transmit information to the brain about the position of the limbs and joints and the tension in the muscles. The patient is asked to stand upright. Romberg's sign is positive if he maintains his posture when his eyes are open but sways and falls when his eyes are closed.

Scrapie associated fibrils. These are the fine structures, seen under the electron microscope that are only found in brains of TSEs. It has been suggested that they are the infective agents themselves, as infectivity can be filtered out with a filter small enough to stop the SAF.

Specified bovine offals. These were the offals of any cow that were thought to represent a risk to the population. Introduced in 1989. Thymus, brain, spinal cord, gut (below duodenum), spleen, tonsils.

Specified bovine materials. These were the parts of a slaughtered cow that were not considered acceptable for human consumption as of around December 1995. The name was changed from SBO because some of the new materials were not offals.

The TSE of sheep or goats.

The compound used in solvents and to attach to proteins (and hence allow them to be electrophoretically separated).

Spongiform encephalopathy.

Spongiform encephalopathy advisory committee. Tyrrell committee. UK

Spongiform encephalopathy research campaign. UK

Species barrier
There appears to be needed much greater a quantity of infectivity to pass a TSE from one species to another rather to a species that is the same as the one from which the sample has come.

Sporadic cases
The cases of CJD (or perhaps other TSEs) that are apparently not associated with a change in the gene of the person developing the disease and not associated with the inoculation of infective material.

It appears that some forms of a TSE in a specific animal may have different characteristics from other forms. These are known as separate strains.

Sulphated-glycan inhibition
The chemicals that have been found to prevent infectivity of inoculated agent.

Tertiary symptoms - n. In the tertiary stage of syphilis, brain damage can cause neurosyphilis resulting in *tabes dorsalis, blindness and general paralysis of the insane.

Thirty Month Rule. The rule introduced in April 1996 by the demand of the farmers in the UK (stated as unnecessary by MAFF) that cattle over 30 months of age should not be used for human food.

tabes dorslis (locomotor ataxia) n.
a form of neurosyphilis occurring 5-20 years after the original venereal infection. The infecting organisms progressively destroy the sensory nerves. Severe stabbing pains in the legs and trunk, an unsteady gait, and loss of bladder control are common. Some patients have blurred vision caused by damage to the optic nerves. Penicillin is used to arrest the progression of this illness. See also syphilis, general paralysis of the insane.

Temporal lobe n.
portion of the brain concerned with appreciation of sound and spoken language.

Transgenic mice.
These are mice carrying a specific gene from another animal. There may be more than one copy of the gene (for instance, in many transgenic mice containing the human PrP gene there may be over 20 copies) and may actually replace the gene that is there normally. The gene is unlikely to be at the same site as the normal gene in the animal chromosome. To insert the gene requires the DNA to be inserted into the fertilized ovum of the animal and hence is very difficult indeed, with many failures.

Transmissible Mink Encephalopathy
or TME. This is the TSE of mink and has been known for around 30 years, particularly in the mink farms of the USA.

Transmissible Spongiform Encephalopathy
A disease that can be transmitted from one animal to another and will produce changes in the brain that are appear similarly to a sponge (i.e. some of the cells are clear when seen down the microscope)

Tubulofilamentous particles
The particles seen under the electron microscope that may be associated with infectivity.

The physical and chemical structure of the amyloid or PrP. Often this includes the way in which the proteins are shaped.

Vertical transmission
The transmission of an illness from the parent(s) to the offspring.

A small item that may be the infective agent of a TSE. It contains protein and nucleic acid.

Small virus-like particles. A term used often in TSE to get around the fact that the infective agent is not yet known.

A infective agent with a specific structure and able to cause its own multiplication after infection of specific cell.


Contact Us

Copyright 1997 - 2012, CJD Voice. All rights reserved.
Link to Us! Graphics used as link buttons.
For problems or questions regarding this web contact