A small protein particle that can transmit an infectious disease. Prion diseases are often referred to as spongiform encephalopathies because of the postmortem appearance of the brain, with large vacuoles in the cerebral cortex and cerebellum. Most mammalian species can develop these diseases. Creutzfeldt-jakob disease is the most common of the prion diseases.
The infective agent(s) responsible for Creutzfeldt-Jakob disease, kuru and possibly other degenerative diseases of the brain in human beings, scrapie in sheep, and bovine spongiform encephalopathy (BSE). They are simple proteins, and unlike viruses, do not contain any nucleic acid. Transmission occurs by ingestion of infected tissue.
Proteinaceous structures (molecules) found in the membrane (surface) of cells, in the brains of all vertebrate animals. In 1982, Dr. Stanley Prusiner discovered that misshapen (mutated) versions could cause the neurodegenerative disease Bovine Spongiform Encephalopathy (BSE) in cattle, and the neurodegenerative diseases Creutzfeld-Jakob Disease (CJD), kuru, Gerstmann-Straussler-Scheinker Syndrome, and Fatal Familial Insomnia (FFI) in humans. Dr. Prusiner named these molecules prions for “proteinaceous infected particle,” because unlike infectious pathogenic bacteria or viruses, prions do not contain DNA. The dye named Congo Red, and IDX (a derivative of the chemotherapeutic doxorubicin) have shown some ability to slow prion-caused neurodegeneration.
An infectious proteinaceous molecule have some of the properties of viruses and are believed to be agents of such diseases as some encephalopathies and Creutzfeldt-Jakob disease.
A particle of protein which contains no nucleic acid, does not trigger an immune response and is not destroyed by extreme heat or cold. Prions are considered to be the agents responsible for scrapie, BSE, and Creutzfeldt-Jakob disease.
A newly-identified class of infectious agents which consist of protein and nothing else, i.e., they do not contain genetic material (nucleic acid (DNA or RNA)), material previously thought necessary to establish an infection in a host. Prion diseases typically are fatal, destroying portions of the brain. They occur quite frequently in animals; examples are scrapie in sheep and goats, “mad cow disease” in Great Britain (more than 130,000 cattle since 1986). In humans, prions have been shown to cause “kuru” in New Guinea, Creutzfeldt-Jakob disease, Gerstmann-Straussler-Scheinker disease, and fatal familial insomnia. Pronounced “preeon”, the word stems from small PROteinaceous INfectious particle.
Short for proteinaceous infectious particle infectious self-reproducing protein structures. Though their exact mechanisms of action and reproduction are unknown, it is now commonly accepted that prions are responsible for a number of previously known but little-understood diseases including kuru, Creutzfeldt- Jakob disease (CJD), and bovine spongiform encephalopathy (BSE or mad cow &s- ease). These diseases affect the structure of brain tissue and all are fatal and unbeatable. Not all prions are dangerous; in fact, prion-like proteins are found naturally in many (perhaps all) plants and animals. Disease occurs when the prion protein undergoes a change from its normal structure to an abnormal one. This change prevents the abnormal protein from being degraded properly. The change may occur spontaneously at an extremely low rate (resulting in sporadic cases) or at a higher rate if various mutations are present.
An aberrant variety of one of the proteins, called PrP, in a brain cell. The result of a gene mutation, prions are stable, resistant to radiation and impervious to the normal cellular processes of degradation. They seem to react with normal PrP, turning it into an abnormal type that then accumulates in brain tissue. Prions are believed to be the infectious agents that cause a group of serious neurological disorders called spongiform encephalopathies. Creutzfeldtjakob disease (CJD), the new variant of CJD linked with bovine spongiform encephalopathy (BSE), and KURU a neurological disorder once related to cannibalism in New Guinea are all diseases in this group that occur in humans. The prion disorders have a long latent period between infection and manifestation of symptoms; they are hard to diagnose until autopsy and there is no cure as yet.
A small proteinaceous infectious particle that is believed to be responsible for central nervous system diseases (spongiform encephalopathies) in humans and other mammals.
A minuscule infectious particle primarily composed of proteins. Prions are responsible for transmitting diseases that lead to the deterioration of the central nervous system. This includes human conditions like Creutzfeldt-Jakob disease and cattle afflictions like bovine spongiform encephalopathy (BSE).
Unlike viruses, prions lack nucleic acids, and their resistance to heat and disinfectants makes them hard to eliminate. Unfortunately, there is currently no treatment accessible for prion-related diseases.