Mariano’s essay

Pineda Torres Gerardo Mariano              Advanced Grammar

Inlingua English Center

Creutzfeldt-Jakob Disease

Introduction

Have you ever heard about mad cow disease (MCD)? If you had, you may want to know that humans can

also get infected. The human version of the MCD is called Creutzfeldt-Jakob Disease (CJD). This rare

disease affects one person in every one million people per year and just in the USA 200 cases are reported

every year. Once infected and after a certain period of time, failing memory, blindness, coma and

involuntary movements appear in patients with CJD. The responsible of this brain disease is a prion. A

prion is a protein that is capable of fold another in order to generate an infectious protein. Usually the fold

or deformation of the protein changes radically their biological roll or even its function as a molecule.

We can distinguish 3 different types of CJD: sporadic (85 percent of people without even been directly

exposed acquired it), hereditary (5-10 percent if there was any case of CJD in the family) and acquired (1

percent of the population that is believed to get infected by direct contact with infected tissue). Nowadays

there is not a standard procedure to diagnosed CJD. Normal medical routine include electroencephalograms

or magnetic resonance imaging for scanning the brain tissue.

Prion is a  term that stands for  proteinaceous infectious agent. A protein can be understood as a long

aggregate of small repetitive molecules, aminoacids. Hemoglobin and DNA are some examples of proteins.

Since these prions can’t replicate or metabolize they are not considered living organisms. However, prions

are considered a high level treat because of its complex diagnosis and no efficient treatments available.

After a period of time the infected proteins will begin to polymerize into an aggregate consisting of tightly

packed sheets. This configuration is very stable, also resistant to chemical and physical degradation, and

once accumulate in the tissue or cells the damage is irreversible.

CJD symptoms usually begin  at the age of 60, and 90 percent of the  patients die after 1 year. Other

symptoms of the CJD are: confusion, dementia, hallucinations, muscle stiffness, personality changes and

sleepiness. As it was mention there is no cure or effective treatment for this condition. Some medication is

recommend to control de aggressive behaviors. At the present time, scientists are working to develop tests

for CJD while the only and certain procedure to find CJD consist in a complete brain biopsy. One of the

treatments develop at NINDS detects the neuronal degeneration using fluids coming from the brain,

obviously this diagnosis is safer than the brain biopsy. The false positive rate reported for this test is about

5 to 10 percent.

Conclusion

CJD is a very rare brain infection cause by a prion witch triggers a very fast degeneration of the brain tissue

leading to hallucinations, involuntary movements, dementia and finally death. Nowadays there  are not

efficient treatments and standard procedures to detect it, but scientist are working on a safer detection of

the disease base on tests results obtained from the brain fluids of the patient. The prion is responsible for

the fold of other proteins leading to structural changes and finally adding layers (polymerizing) of these

proteins to build tightly packed sheets. Scientists are beginning to investigate prion related diseases like

CJD and other related.  We have to continue the support for prion researches in order to find better and

more efficient treatments.