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Biological hazards
Published in Sue Reed, Dino Pisaniello, Geza Benke, Principles of Occupational Health & Hygiene, 2020
Margaret Davidson, Ryan Kift, Sue Reed
Prions are microscopic self-replicating proteins that cause neurodegenerative diseases such as classical Creutzfeldt-Jakob Disease (CJD) and variant CJD (vCJD) in humans, and bovine spongiform encephalopathy (BSE) in animals. These diseases are always fatal. Prions are infectious proteins that replicate by acting as a template that causes normal cellular proteins to reshape into prion proteins. Spasmodic cases of classical CJD have been recorded in Australian since 1970; however, there have been no reported cases of vCJD. Australia is considered a negligible-risk country for BSE (NSW Health, 2015).
Chemical and biological health hazards and risk control
Published in Phil Hughes, Ed Ferrett, Introduction to Health and Safety in Construction, 2015
A number of diseases, including bovine spongiform encephalopathy (BSE) in cattle and Creutzfeldt–Jakob disease (CJD) in humans, are caused by another biological agent known as a prion. A prion is an infectious agent that is composed primarily of protein. Such agents induce existing substances, called polypeptides, in the host organism to take on a rogue form. All known prion diseases affect the structure of the brain or other neural tissue, are currently untreatable and are always fatal.
Polymeric Nanoparticles for Drug Delivery
Published in Severian Dumitriu, Valentin Popa, Polymeric Biomaterials, 2020
Karine Andrieux, Julien Nicolas, Laurence Moine, Gillian Barratt
5.4.2.2.2.1.2 PEGylated NPs PEGylated NPs were prepared using a poly[methoxypoly(ethylene glycol)-co-(hexadecyl cyanoacrylate)] (P(MePEGCA-co-HDCA)) (MePEGCA/HDCA, 1:4) copolymer (Peracchia et al., 1998, Nicolas et al., 2008). In this technology, the PEG is covalently attached to the NPs, avoiding the possibility of PEG desorption. These P(MePEGCA-co-HDCA) NPs have shown long-circulating properties in vivo (Peracchia et al., 1999). They have demonstrated their capacity to reach the brain in a model of experimental allergic encephalomyelitis (EAE) rats (Calvo et al., 2002) in which the BBB permeability is increased by inflammation. Two mechanisms have been proposed: passive diffusion as a result of the increase of BBB permeability and transport by NP-containing macrophages infiltrating into these inflammatory tissues. Furthermore, these PEGylated NPs also showed a higher uptake by the brain of scrapie-infected animals, which may be useful for targeting drugs for the treatment of prion disease (Calvo et al., 2001b).
Principles of risk decision-making
Published in Journal of Toxicology and Environmental Health, Part B, 2022
Daniel Krewski, Patrick Saunders-Hastings, Patricia Larkin, Margit Westphal, Michael G. Tyshenko, William Leiss, Maurice Dusseault, Michael Jerrett, Doug Coyle
Prion diseases are caused by a misfolded form of the prion protein, which leads to neurodegeneration through propagation of the misfolded form within neural tissue. Fatal prion diseases have been described in multiple species, including scrapie in sheep, bovine spongiform encephalopathy (BSE) or ‘mad cow disease’ in cattle, chronic wasting disease (CWD) in deer and elk, and variant Creutzfeldt-Jacob disease (vCJD) in humans. Prion diseases may be transmissible between species: for example, BSE is thought to have originated from the inclusion of sheep offal in the diets of cattle in the United Kingdom, with consumption of beef containing the BSE agent leading to the development of vCJD in humans. The outbreak of the BSE epidemic in the UK in 1986 spread to other countries, and enormous negative socioeconomic impacts in BSE-affected countries (Leiss et al. 2010). Human prion disease may be transmitted by blood transfusion. Infectious prion proteins were detected in fertility drugs from human urine, presumably arising from donors with asymptomatic vCJD (Van Dorsselaer et al. 2011). There remain concerns regarding species transmission of CWD from deer and elk to other cervid species, including caribou (Haley and Hoover 2015). There is also increasing evidence that propagated protein misfolding plays a role in other neurodegenerative diseases, including Alzheimer’s disease, Parkinson’s disease, and amyotrophic lateral sclerosis (Herms and Dorostkar 2016). At present, there are no effective medical interventions for prion diseases, although a promising vaccine against CWD is currently under development (Goñi et al. 2015).
Estimating the rate of prion aggregate amplification in yeast with a generation and structured population model
Published in Inverse Problems in Science and Engineering, 2018
H. T. Banks, Kevin B. Flores, Christine R. Langlois, Tricia R. Serio, Suzanne S. Sindi
Prions are misfolded proteins associated with a variety of fatal, untreatable neurodegenerative disorders in mammals [1–3]. Many of these diseases are associated with aging and, as such, visible symptoms can take decades to manifest. Because of this, the single celled yeast S. cerevisiae has emerged as a model for prion onset because prion phenotypes appear within hours. Additionally, since prions in yeast are associated with harmless heritable phenotypes, rather than disorders, this system allows a unique opportunity to observe prions not possible for mammals. Finally, the experimental tractability of the yeast system facilitates the observations of prion dynamics and manipulations in vivo [4,5].
Machine learning algorithms for the diagnosis of Alzheimer and Parkinson disease
Published in Journal of Medical Engineering & Technology, 2023
R S Nancy Noella, J Priyadarshini
It is the rarest form of dementia. It occurs when prion protein, which is found throughout the body and accumulates in the brain to fold into the same abnormal shape. CJD develops very quickly, and the affected patient often dies within a year of diagnosis.