Prion Diseases

Innovation in neurosurgery

As medical students, we don't get much intra-curricular exposure to surgery. Then there is the neurophobia, a chronic condition whose main symptom is the inability to apply knowledge of neuroscience to clinical situations. ...

Sep 16, 2015
popularity20 comments 0

Prion protein protects against epilepsy

In the most systematic and rigorous study conducted thus far in its field, the prion protein (PrPC) was clearly shown to play a role in preventing the onset of epileptic seizures. PrPC is perhaps best known in its 'degenerate' ...

Jul 09, 2015
popularity19 comments 0

Transmissible spongiform encephalopathies (TSEs), also known as prion diseases, are a group of progressive conditions that affect the brain and nervous system of many animals, including humans. According to the most widespread hypothesis they are transmitted by prions, though some other data suggest an involvement of a Spiroplasma infection. Mental and physical abilities deteriorate and myriad tiny holes appear in the cortex causing it to appear like a sponge (hence 'spongiform') when brain tissue obtained at autopsy is examined under a microscope. The disorders cause impairment of brain function, including memory changes, personality changes and problems with movement that worsen over time. Prion diseases of humans include classic Creutzfeldt–Jakob disease, new variant Creutzfeldt–Jakob disease (nvCJD, a human disorder related to mad cow disease), Gerstmann–Sträussler–Scheinker syndrome, fatal familial insomnia and kuru. These conditions form a spectrum of diseases with overlapping signs and symptoms.

Unlike other kinds of infectious disease which are spread by microbes, the infectious agent in TSEs is a specific protein called prion protein. Misshaped prion proteins carry the disease between individuals and cause deterioration of the brain. TSEs are unique diseases in that their aetiology may be genetic, sporadic or infectious via ingestion of infected foodstuffs and via iatrogenic means (e.g. blood transfusion). Most TSEs are sporadic and occur in an animal with no prion protein mutation. Inherited TSE occurs in animals carrying a rare mutant prion allele, which expresses prion proteins that contort by themselves into the disease-causing conformation. Transmission occurs when healthy animals consume tainted tissues from others with the disease. In recent times a type of TSE called bovine spongiform encephalopathy (BSE) spread in cattle in an epidemic fashion. This occurred because cattle were fed the processed remains of other cattle, a practice now banned in many countries. The epidemic could have begun with just one cow with sporadic disease.

Prions cannot be transmitted through the air or through touching or most other forms of casual contact. However, they may be transmitted through contact with infected tissue, body fluids, or contaminated medical instruments. Normal sterilization procedures such as boiling or irradiating materials fail to render prions non-infective.

This text uses material from Wikipedia licensed under CC BY-SA

Latest Spotlight News

Artificial heart design features porous plastic foam

Artificial hearts with multiple moving parts increase the chance of failure; scientists have worked up a device which is a single piece. No less interesting is the material they used; the team is taking a page out of soft ...

Can exercise be replaced with a pill?

Everyone knows that exercise improves health, and ongoing research continues to uncover increasingly detailed information on its benefits for metabolism, circulation, and improved functioning of organs such as the heart, ...

Study sheds light on role genes play in memory retention

(Medical Xpress)—A combined team of researchers from the Institute for Basic Science and Seoul National University, both in South Korea, has found three types of repressive regulations in the hippocampus of mice that impact ...

Videos reveal how HIV spreads in real time

How retroviruses like HIV spread in their hosts had been unknown—until a Yale team devised a way to watch it actually happen in a living organism. The elaborate and sometimes surprising steps the virus takes to reach and ...