25 research outputs found
Transmission of Chronic Wasting Disease Identifies a Prion Strain Causing Cachexia and Heart Infection in Hamsters
Chronic wasting disease (CWD) is an emerging prion disease of free-ranging and captive cervids in North America. In this study we established a rodent model for CWD in Syrian golden hamsters that resemble key features of the disease in cervids including cachexia and infection of cardiac muscle. Following one to three serial passages of CWD from white-tailed deer into transgenic mice expressing the hamster prion protein gene, CWD was subsequently passaged into Syrian golden hamsters. In one passage line there were preclinical changes in locomotor activity and a loss of body mass prior to onset of subtle neurological symptoms around 340 days. The clinical symptoms included a prominent wasting disease, similar to cachexia, with a prolonged duration. Other features of CWD in hamsters that were similar to cervid CWD included the brain distribution of the disease-specific isoform of the prion protein, PrPSc, prion infection of the central and peripheral neuroendocrine system, and PrPSc deposition in cardiac muscle. There was also prominent PrPSc deposition in the nasal mucosa on the edge of the olfactory sensory epithelium with the lumen of the nasal airway that could have implications for CWD shedding into nasal secretions and disease transmission. Since the mechanism of wasting disease in prion diseases is unknown this hamster CWD model could provide a means to investigate the physiological basis of cachexia, which we propose is due to a prion-induced endocrinopathy. This prion disease phenotype has not been described in hamsters and we designate it as the ‘wasting’ or WST strain of hamster CWD
ERAU MICROJET TEAM
In the late 1960’s the aerospace industry would be changed forever. General Aviation aircraft were being built and sold by the thousands, and for the first time ever pilots with limited mechanical skills could build their own aircraft from “kits.” It wasn\u27t long until one individual, Jim Bede, revolutionized the kit aircraft market with his quick-build aircraft. The famed Bede BD-5 was affordable to the average individual, easy to assemble, and had impressive performance.
Aircraft performance data from Bede was scarce and questionable. Leading home-builders to question the safety of their aircraft, this is what the ERAU MicroJET Team set out to fix. We are conducting a full air-frame and performance analysis of the Bede BD-5, all while Embry-Riddle Aeronautical University students from all majors aid in the engineering, building, and testing improvements on our very own Bede BD-5. Through this, our research will benefit the 5000+ BD-5 owners worldwide
Instability of rRNA operons in Bacillus subtilis.
Many laboratory strains of Bacillus subtilis contain 9 rather than 10 rRNA operons due to deletions occurring within the rrnJ-rrnW or rrnI-rrnH-rrnG gene cluster. These operons are members of two sets of closely spaced clusters located in the cysA-aroI region. Analysis of rescued DNA from integrants with insertions into rrnG and rrnH indicated that these tandemly arranged operons allowed frequent deletions of an rrn operon equivalent. These events may arise spontaneously by intrachromosomal recombination or by simultaneous double crossovers with a multimeric integrative plasmid
Prion Strain Mutation Determined by Prion Protein Conformational Compatibility and Primary Structure
Charged tmRNA but not tmRNA-mediated proteolysis is essential for Neisseria gonorrhoeae viability
tmRNA, through its tRNA and mRNA properties, adds short peptide tags to abnormal proteins, targeting these proteins for proteolytic degradation. Although the conservation of tmRNA throughout the bacterial kingdom suggests that it must provide a strong selective advantage, it has not been shown to be essential for any bacterium. We report that tmRNA is essential in Neisseria gonorrhoeae. Although tagging per se appears to be required for gonococcal viability, tagging for proteolysis does not. This suggests that the essential roles of tmRNA in N.gonorrhoeae may include resolving stalled translation complexes and/or preventing depletion of free ribosomes. Although derivatives of N.gonorrhoeae expressing Escherichia coli tmRNA as their sole tmRNA were isolated, they appear to form colonies only after acquiring an extragenic suppressor(s)