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Fast, broad-range disinfection of bacteria, fungi, viruses and prions.

Effective disinfectants are of key importance for the safe handling and reprocessing of surgical instruments. This study tested whether new formulations containing SDS, NaOH and 1-propanol (n-propanol) are simultaneously active against a broad range of pathogens including bacteria, fungi, non-enveloped viruses and prions. Inactivation and disinfection were examined in suspension and on carriers, using coagulated blood or brain homogenate as an organic contaminant. Coomassie blue staining was used to assess whether the formulations undesirably fixed proteins to rough surfaces. A mixture of 0.2 …

Prions in skeletal muscles of deer with chronic wasting disease.

The emergence of chronic wasting disease (CWD) in deer and elk in an increasingly wide geographic area, as well as the interspecies transmission of bovine spongiform encephalopathy to humans in the form of variant Creutzfeldt Jakob disease, have raised concerns about the zoonotic potential of CWD. Because meat consumption is the most likely means of exposure, it is important to determine whether skeletal muscle of diseased cervids contains prion infectivity. Here bioassays in transgenic mice expressing cervid prion protein revealed the presence of infectious prions in skeletal muscles of CWD-i…

[Prions, epidemic of Creutzfeldt-Jakob variant disease and global emergency].

We present here the current understanding of "prion" theory and global risk for epidemics of variant Creutzfeldt-Jakob disease (vCJD). Prion is the infectious agent of all transmissible spongiform encephalopaties (TSEs). It is regarded as an aggregate of a pathological conformer (PrPSc) of a normal cellular glycoprotein (PrPC) encoded by a gene, in humans on chromosome 20. The differences between PrPSc and PrPC are largely if not exclusively conformational; PrPC is mostly alpha-helical while PrPSc, beta-pleeted. Furthermore, mutations within the coding sequence (open reading frame) of PrP gene

Infectivity of scrapie prions bound to a stainless steel surface.

BACKGROUND: The transmissible agent of Creutzfeldt-Jakob disease (CJD) is not readily destroyed by conventional sterilization and transmissions by surgical instruments have been reported. Decontamination studies have been carried out thus far on solutions or suspensions of the agent and may not reflect the behavior of surface-bound infectivity. MATERIALS AND METHODS: As a model for contaminated surgical instruments, thin stainless-steel wire segments were exposed to scrapie agent, washed exhaustively with or without treatment with 10% formaldehyde, and implanted into the brains of indicator m

Replication of scrapie prions in hamster eyes precedes retinal degeneration.

Progressive degeneration of outer retinal structures occurs in hamsters with scrapie. In order to determine the relationship between histopathologic changes and replication of the scrapie agent, hamsters were inoculated intracerebrally with approximately 10(7) ID50 units. Animals sacrificed at 50 days after inoculation showed no signs of neurologic dysfunction, but had high titers of the scrapie agent or prions in both neural and nonneural portions of the eye. Prion titers in retina were greater than 10(7) ID50 units/ml of 10% (w/v) homogenate and equal to those found in optic nerve and brain.…

Assessment of the Zoonotic Potential of Atypical Scrapie Prions in Humanized Mice Reveals Rare Phenotypic Convergence but Not Identity With Sporadic Creutzfeldt-Jakob Disease Prions.

BACKGROUND: Atypical/Nor98 scrapie (AS) is an idiopathic infectious prion disease affecting sheep and goats. Recent findings suggest that zoonotic prions from classical bovine spongiform encephalopathy (C-BSE) may copropagate with atypical/Nor98 prions in AS sheep brains. Investigating the risk AS poses to humans is crucial. METHODS: To assess the risk of sheep/goat-to-human transmission of AS, we serially inoculated brain tissue from field and laboratory isolates into transgenic mice overexpressing human prion protein (Met129 allele). We studied clinical outcomes as well as presence of prion…

Генетика прионовых заболеваний.

Прионские заболевания являются трансмиссивными, смертельными нейродегенеративными заболеваниями, к числу которых относятся слезоточивость и энцефалопатия говядины (BSE) у животных и болезнь Креуцфельдта-Якоба (CJD) у человека. Прионский белковый ген (PRNP) является основным генетическим определяющим фактором уязвимости, однако некоторые исследования показывают, что другие гены также важны. В двух недавних исследованиях, посвященных широкополосной ассоциации генома человека, были выявлены четыре новых места, представляющих интерес: ZBTB38-RASA2 в UK CJD и MTMR7 и NNAS2 в варианте CJD. В дополни

Ethics in prion disease.

This paper is intended to discuss some of the scientific and ethical issues that are created by increased research efforts towards earlier diagnosis, as well as to treatment of, human prion diseases (and related dementias), including the resulting consequences for individuals, their families, and society. Most patients with prion disease currently are diagnosed when they are about 2/3 of the way through their disease course (Geschwind et al., 2010a; Paterson et al., 2012b), when the disease has progressed so far that even treatments that stop the disease process would probably have little bene

Иммунобиология прионовых заболеваний.

Люди, инфицированные прионами, становятся жертвами повреждения мозга, а прионские инфекции по-прежнему являются неизмеримо смертельными. Однако многие важные шаги в патогенезе приона происходят в лимфатических органах и предшествуют вторжению в центральную нервную систему. За последние два десятилетия многому удалось научиться в связи с клеточными и молекулярными механизмами вторжения прионовых лимфоманов. Эти свойства являются диагностически полезными и, например, способствуют доклиническому диагностированию заболевания креуцфельдта-Якоба в миндалинах. Кроме того, ранняя колонизация лимфоидны

Совпадение в аннотации оригинала
Individuals infected with prions succumb to brain damage, and prion infections continue to be inexorably lethal. However, many crucial steps in prion pathogenesis occur in lymphatic organs and precede invasion of the central nervous system. In the past two decades, a great deal has been learnt concerning the cellular and molecular mechanisms of prion lymphoi…

Animal prion diseases.

Prion diseases occur in many animal species, most notably in ruminants. While scrapie in sheep has been recognised for three centuries and goat scrapie has been recognised for decades, BSE in cattle is a relatively novel disease which was first diagnosed in the UK in the mid 1980s. BSE was most likely caused through dietary exposure to animal feed contaminated with prions and disease was subsequently transmitted to people. The BSE epidemic is almost at an end, but the recent identification of so called atypical forms of BSE and scrapie pose many questions about the possible spectrum of prion d…

Tetracyclines and prion infectivity.

In the last decade information has accumulated on the potential anti-prion activity of polycyclic compounds. Initially we showed that the antitumoral idodoxorubicin reduced the infectivity in experimental scrapie. On the basis of the chemical homology with anthracyclines, we rapidly moved to tetracyclines, compounds that are safer and widely used as antibiotics in clinical practice. The tetracyclines, essentially doxycycline and minocycline, were characterized as a therapeutical tool in transmissible spongiform encephalopathies (TSE) through the cell-free condition, in cellular and animal mode

Prion protein oligomerization.

The PrP propensity to adopt different structures is tightly linked to transmissible spongiform encephalopathies (TSE) which include Creutzfeldt-Jakob disease (CJD), Gerstmann-Sträussler-Scjeinker (GSS) and Kuru syndrome. In most cases, TSE is associated with the accumulation in the brain of an abnormally folded protease-resistant protein, PrP Sc or PrPres, which is derived from a cellular host-encoded protease-sensitive conformer, designated PrP C. The prion propagation in the brain is postulated to occur via a conformational change of PrP C into the amyloidogenic form PrP Sc, characterized by

Prion protein glycosylation.

The transmissible spongiform encephalopathies (TSE), or prion diseases are a group of transmissible neurodegenerative disorders of humans and animals. Although the infectious agent (the 'prion') has not yet been formally defined at the molecular level, much evidence exists to suggest that the major or sole component is an abnormal isoform of the host encoded prion protein (PrP). Different strains or isolates of the infectious agent exist, which exhibit characteristic disease phenotypes when transmitted to susceptible animals. In the absence of a nucleic acid genome it has been hard to accommod

[Prion diseases as zoonosis].

Prion diseases such as bovine spongiform encephalopathy (BSE) have been recognized as zoonosis since the existence of variant Creutzfeldt-Jakob disease (vCJD) was reported in 1996. BSE became a serious social problem even in Japan after the first BSE case was found in 2001. The incidence of BSE in EU and UK appears declining, and the vCJD incidence also shows a tendency to decrease. On the contrary, fears for the spread of BSE became actual problems: BSE occurrence outside of EU, transmission of vCJD by blood transfusion, and the first vCJD case in Japan. To prevent further spread and to reduc

Doppel: the prion's double.

Doppel (Dpl) is a PrP-like protein, coded by a gene named PRND, located near the PRNP (prion proten coding gene) locus. Human Dpl is a 179-amino acid protein showing approximately 25% sequence identity with the carboxyproximal two thirds of the human cellular prion protein (PrPC). A comparison of the structures of Dpl and PrP(C) reveals similarities in the secondary structure and topology. Apart from their structural similarities, the PrP and Dpl proteins seem to have different functions. The Prnd gene is expressed in mouse embryos; in adult mice its transcripts are present in heart, mammary g

Prion diseases and the spleen.

Transmissible spongiform encephalopathies are fatal neurodegenerative disorders that include Creutzfeldt-Jakob disease in humans, bovine spongiform encephalopathy and scrapie in sheep and goats. Transmissible spongiform encephalopathies are thought by some to result from changes in the conformation of a membrane glycoprotein called PrPC (prion protein) into a pathogenic form, PrPSc, which constitutes the major component of an unprecedented type of infectious particle supposedly devoid of nucleic acid. Although there is no primary immunological response to the infectious agent, several lines of