| pathways of prion spread during early chronic wasting disease in deer. | among prion infections, two scenarios of prion spread are generally observed: (a) early lymphoid tissue replication or (b) direct neuroinvasion without substantial antecedent lymphoid amplification. in nature, cervids are infected with chronic wasting disease (cwd) prions by oral and nasal mucosal exposure, and studies of early cwd pathogenesis have implicated pharyngeal lymphoid tissue as the earliest sites of prion accumulation. however, knowledge of chronological events in prion spread during ... | 2017 | 28250130 |
| endogenous brain lipids inhibit prion amyloid formation in vitro. | the normal cellular prion protein (prp(c)) resides in detergent-resistant outer membrane lipid rafts in which conversion to the pathogenic misfolded form is believed to occur. once misfolding occurs, the pathogenic isoform polymerizes into highly stable amyloid fibrils. in vitro assays have demonstrated an intimate association between prion conversion and lipids, specifically phosphatidylethanolamine, which is a critical cofactor in the formation of synthetic infectious prions. in the current wo ... | 2017 | 28202758 |
| molecular mechanisms of chronic wasting disease prion propagation. | prion disease epidemics, which have been unpredictable recurrences, are of significant concern for animal and human health. examples include kuru, once the leading cause of death among the fore people in papua new guinea and caused by mortuary feasting; bovine spongiform encephalopathy (bse) and its subsequent transmission to humans in the form of variant creutzfeldt-jakob disease (vcjd), and repeated examples of large-scale prion disease epidemics in animals caused by contaminated vaccines. the ... | 2017 | 28193766 |
| efsa proposes surveillance scheme for chronic wasting disease. | | 2017 | 28154211 |
| de novo generation of a unique cervid prion strain using protein misfolding cyclic amplification. | substantial evidence supports the hypothesis that prions are misfolded, infectious, insoluble, and protease-resistant proteins (prp(res)) devoid of instructional nucleic acid that cause transmissible spongiform encephalopathies (tses). protein misfolding cyclic amplification (pmca) has provided additional evidence that prpres acts as a template that can convert the normal cellular prion protein (prp(c)) present in uninfected normal brain homogenate (nbh) into the infectious misfolded prp(res) is ... | 2017 | 28144628 |
| current evidence on the transmissibility of chronic wasting disease prions to humans-a systematic review. | a number of prion diseases affect humans, including creutzfeldt-jakob disease; most of these are due to genetic mutations in the affected individual and occur sporadically, but some result from transmission of prion proteins from external sources. of the known animal prion diseases, only bovine spongiform encephalopathy prions have been shown to be transmissible from animals to humans under non-experimental conditions. chronic wasting disease (cwd) is a prion disease that affects cervids (e.g., ... | 2017 | 28139079 |
| the structure of mammalian prions and their aggregates. | prion diseases, such as creutzfeldt-jakob disease in humans, bovine spongiform encephalopathy in cattle, chronic wasting disease in cervids (i.e., deer, elk, moose, and reindeer), and sheep scrapie, are caused by the misfolding of the cellular prion protein (prp(c)) into a disease-causing conformer (prp(sc)). prp(c) is a normal, gpi-anchored protein that is expressed on the surface of neurons and other cell types. the structure of prp(c) is well understood, based on studies of recombinant prp, w ... | 2017 | 28109330 |
| examination of mycobacterium avium subspecies paratuberculosis mixed genotype infections in dairy animals using a whole genome sequencing approach. | many pathogenic mycobacteria are known to cause severe disease in humans and animals. m. avium subspecies paratuberculosis (map) is the causative agent of johne's disease-a chronic wasting disease affecting ruminants such as cattle and sheep, responsible for significant economic losses in the dairy and beef industries. due to the lack of treatment options or effective vaccines, mitigating losses can be difficult. in addition, the early stages of map infection may occur in asymptomatic hosts that ... | 2016 | 27994984 |
| clay components in soil dictate environmental stability and bioavailability of cervid prions in mice. | chronic wasting disease (cwd) affects cervids and is the only known prion disease to affect free-ranging wildlife populations. cwd spread continues unabated, and exact mechanisms of its seemingly facile spread among deer and elk across landscapes in north america remain elusive. here we confirm that naturally contaminated soil contains infectious cwd prions that can be transmitted to susceptible model organisms. we show that smectite clay content of soil potentiates prion binding capacity of dif ... | 2016 | 27933048 |
| multigenetic characterization of 'candidatus xenohaliotis californiensis'. | 'candidatus xenohaliotis californiensis' (or ca.xc) is the aetiological agent of withering syndrome, a chronic wasting disease affecting most if not all north american species of abalone, and has been described as a rickettsiales-like prokaryote. genetic data regarding this species are limited to the 16s rrna gene. the inability to grow it axenically has hindered its genetic and genomic characterization and, in consequence, a thorough analysis of its systematics. here, we amplified and sequenced ... | 2017 | 27902186 |
| chronic wasting disease in white-tailed deer: infection, mortality, and implications for heterogeneous transmission. | chronic wasting disease (cwd) is a fatal neurodegenerative disease affecting free-ranging and captive cervids that now occurs in 24 u.s. states and two canadian provinces. despite the potential threat of cwd to deer populations, little is known about the rates of infection and mortality caused by this disease. we used epidemiological models to estimate the force of infection and disease-associated mortality for white-tailed deer in the wisconsin and illinois cwd outbreaks. models were based on a ... | 2016 | 27870037 |
| horizontal transmission of chronic wasting disease in reindeer. | we challenged reindeer by the intracranial route with the agent of chronic wasting disease sourced from white-tailed deer, mule deer, or elk and tested for horizontal transmission to naive reindeer. reindeer were susceptible to chronic wasting disease regardless of source species. horizontal transmission occurred through direct contact or indirectly through the environment. | 2016 | 27869594 |
| early and non-invasive detection of chronic wasting disease prions in elk feces by real-time quaking induced conversion. | chronic wasting disease (cwd) is a fatal prion disease of wild and captive cervids in north america. prions are infectious agents composed of a misfolded version of a host-encoded protein, termed prpsc. infected cervids excrete and secrete prions, contributing to lateral transmission. geographical distribution is expanding and case numbers in wild cervids are increasing. recently, the first european cases of cwd have been reported in a wild reindeer and two moose from norway. therefore, methods ... | 2016 | 27829062 |
| intra-host mathematical model of chronic wasting disease dynamics in deer (odocoileus). | bioassays of native cervid hosts have established the presence of infectious chronic wasting disease (cwd) prions in saliva, blood, urine, and feces of clinically diseased and pre-clinical infected deer. the intra-host trafficking of prions from the time of initial infection to shedding has been less well defined. we created a discrete-time compartmentalized model to simulate the misfolding catalysis, trafficking, and shedding of infectious prions throughout the organ systems of cwd-infected cer ... | 2016 | 27537196 |
| modeled impacts of chronic wasting disease on white-tailed deer in a semi-arid environment. | white-tailed deer are a culturally and economically important game species in north america, especially in south texas. the recent discovery of chronic wasting disease (cwd) in captive deer facilities in texas has increased concern about the potential emergence of cwd in free-ranging deer. the concern is exacerbated because much of the south texas region is a semi-arid environment with variable rainfall, where precipitation is strongly correlated with fawn recruitment. further, the marginally pr ... | 2016 | 27711208 |
| assessment of the prpc amino-terminal domain in prion species barriers. | chronic wasting disease (cwd) in cervids and bovine spongiform encephalopathy (bse) in cattle are prion diseases that are caused by the same protein-misfolding mechanism, but they appear to pose different risks to humans. we are interested in understanding the differences between the species barriers of cwd and bse. we used real-time, quaking-induced conversion (rt-quic) to model the central molecular event in prion disease, the templated misfolding of the normal prion protein, prp(c), to a path ... | 2016 | 27654299 |
| first case of chronic wasting disease in europe in a norwegian free-ranging reindeer. | chronic wasting disease (cwd) is a fatal contagious prion disease in cervids that is enzootic in some areas in north america. the disease has been found in deer, elk and moose in the usa and canada, and in south korea following the importation of infected animals. here we report the first case of cwd in europe, in a norwegian free-ranging reindeer in southern norway. the origin of the disease is unknown. until now a low number of cervids, and among them a few reindeer, have been tested for cwd i ... | 2016 | 27641251 |
| chronic wasting disease drives population decline of white-tailed deer. | chronic wasting disease (cwd) is an invariably fatal transmissible spongiform encephalopathy of white-tailed deer, mule deer, elk, and moose. despite a 100% fatality rate, areas of high prevalence, and increasingly expanding geographic endemic areas, little is known about the population-level effects of cwd in deer. to investigate these effects, we tested the null hypothesis that high prevalence cwd did not negatively impact white-tailed deer population sustainability. the specific objectives of ... | 2016 | 27575545 |
| caribou consumption in northern canadian communities. | chronic wasting disease (cwd) is a transmissible spongiform encephalopathy (tse) found in both farmed and wild deer, elk, and moose in the united states and canada. surveillance efforts in north america identified the geographical distribution of the disease and mechanisms underlying distribution, although the possibility of transmission to other cervids, including caribou, and noncervids, including humans, is not well understood. because of the documented importance of caribou (rangifer tarandu ... | 2016 | 27556568 |
| expert elicitation on the uncertainties associated with chronic wasting disease. | a high degree of uncertainty exists for chronic wasting disease (cwd) transmission factors in farmed and wild cervids. evaluating the factors is important as it helps to inform future risk management strategies. expert opinion is often used to assist decision making in a number of health, science, and technology domains where data may be sparse or missing. using the "classical model" of elicitation, a group of experts was asked to estimate the most likely values for several risk factors affectin ... | 2016 | 27556566 |
| using expert judgments to improve chronic wasting disease risk management in canada. | abstarct chronic wasting disease (cwd) is a neurodegenerative, protein misfolding disease affecting cervids in north america in epidemic proportions. while the existence of cwd has been known for more than 40 years, risk management efforts to date have not been able to curtail the spread of this condition. an expert elicitation exercise was carried out in may 2011 to obtain the views of international experts on both the etiology of cwd and possible cwd risk management strategies. this study pres ... | 2016 | 27556565 |
| applications of mathematical modeling in managing the spread of chronic wasting disease (cwd) in wild deer under alternative harvesting scenarios. | the application of a recently developed mathematical model for predicting the spread of chronic wasting disease (cwd) in wild deer was assessed under different scenarios where harvesting is employed in disease management. a process-based mathematical model for cwd transmission in wild deer populations was recently developed and parameterized by al-arydah et al. (2011) to provide a scientific basis for understanding the factors that affect spread of cwd and evaluate concomitant disease-control st ... | 2016 | 27556563 |
| systematic review of management strategies to control chronic wasting disease in wild deer populations in north america. | chronic wasting disease (cwd) is a contagious, fatal prion disease affecting cervids in a growing number of regions across north america. projected deer population declines and concern about potential spread of cwd to other species warrant strategies to manage this disease. control efforts to date have been largely unsuccessful, resulting in continuing spread and increasing prevalence. this systematic review summarizes peer-reviewed published reports describing field-applicable cwd control strat ... | 2016 | 27549119 |
| chronic wasting disease of deer - is the battle to keep europe free already lost? | | 2016 | 27474059 |
| primary transmission of chronic wasting disease versus scrapie prions from small ruminants to transgenic mice expressing ovine or cervid prion protein. | development of mice expressing either ovine (tg338) or cervid (tgelk) prion protein (prp) have aided in characterization of scrapie and chronic wasting disease (cwd), respectively. experimental inoculation of sheep with cwd prions has demonstrated the potential for interspecies transmission but, infection with cwd versus classical scrapie prions may be difficult to differentiate using validated diagnostic platforms. in this study, mouse bioassay in tg338 and tgelk was utilized to evaluate transm ... | 2016 | 27393736 |
| enhanced prion detection in biological samples by magnetic particle extraction and real-time quaking-induced conversion. | prions have been demonstrated in body fluids and excreta using bioassay, but at levels too low for detection by conventional direct-detection assays. more rapid and sensitive detection of prions in these clinically accessible specimens would be valuable for diagnosis and investigations of transmission, environmental impact, and interventions. in addition to very low concentrations of prions, in vitro amplification assays are challenged by the presence of inhibitors in these complex sources. here ... | 2016 | 27233771 |
| dietary magnesium and copper affect survival time and neuroinflammation in chronic wasting disease. | chronic wasting disease (cwd), the only known wildlife prion disease, affects deer, elk and moose. the disease is an ongoing and expanding problem in both wild and captive north american cervid populations and is difficult to control in part due to the extreme environmental persistence of prions, which can transmit disease years after initial contamination. the role of exogenous factors in cwd transmission and progression is largely unexplored. in an effort to understand the influence of environ ... | 2016 | 27216881 |
| detection and quantification of cwd prions in fixed paraffin embedded tissues by real-time quaking-induced conversion. | traditional diagnostic detection of chronic wasting disease (cwd) relies on immunodetection of misfolded cwd prion protein (prp(cwd)) by western blotting, elisa, or immunohistochemistry (ihc). these techniques require separate sample collections (frozen and fixed) which may result in discrepancies due to variation in prion tissue distribution and assay sensitivities that limit detection especially in early and subclinical infections. here, we harness the power of real-time quaking induced conver ... | 2016 | 27157060 |
| a swainsonine survey of north american astragalus and oxytropis taxa implicated as locoweeds. | swainsonine, an indolizidine alkaloid with significant physiological activity, is an α-mannosidase and mannosidase ii inhibitor that causes lysosomal storage disease and alters glycoprotein processing. swainsonine is found in a number of plant species worldwide, and causes severe toxicosis in livestock grazing these plants, leading to a chronic wasting disease characterized by weight loss, depression, altered behavior, decreased libido, infertility, and death. swainsonine has been detected in 19 ... | 2016 | 27085305 |
| defining and assessing analytical performance criteria for transmissible spongiform encephalopathy-detecting amyloid seeding assays. | transmissible spongiform encephalopathies (tses) are infectious, fatal neurodegenerative diseases that affect production animal health, and thus human food safety. enhanced tse detection methods mimic the conjectured basis for prion replication, in vitro; biological matrices can be tested for prion activity via their ability to convert recombinant cellular prion protein (prp) into amyloid fibrils; fluorescent spectra changes of amyloid-binding fluorophores in the reaction vessel detect fibril fo ... | 2016 | 27068712 |
| the stress of prion disease. | prion diseases are fatal neurodegenerative disorders that include scrapie of sheep, bovine spongiform encephalopathy of cattle, chronic wasting disease of cervids, and creutzfeldt-jakob disease (cjd) of humans. the etiology for prion diseases can be infectious, sporadic, or hereditary. however, the common denominator for all types is the formation of a transmissible agent composed of a β-sheet-rich, misfolded version of the host-encoded prion protein (prp(c)), known as prp(sc). prp(sc) self-repl ... | 2016 | 27060771 |
| limited amplification of chronic wasting disease prions in the peripheral tissues of intracerebrally inoculated cattle. | chronic wasting disease (cwd) is a fatal neurodegenerative disease, classified as a prion disease or transmissible spongiform encephalopathy (tse) similar to bovine spongiform encephalopathy (bse). cervids affected by cwd accumulate an abnormal protease-resistant prion protein throughout the central nervous system (cns), as well as in both lymphatic and excretory tissues - an aspect of prion disease pathogenesis not observed in cattle with bse. using seeded amplification through real-time quakin ... | 2016 | 27031704 |
| regulatory t cells and immune profiling in johne's disease lesions. | johne's disease, caused by infection with mycobacterium avium subspecies paratuberculosis (map), is a chronic wasting disease of ruminants. hallmark symptoms of clinical johne's disease include diarrhea, progressive weight loss, and premature death; symptoms due largely to chronic inflammation in the small intestine. map colonizes resident macrophages within the ileum of the small intestine, subsequently establishing a persistent infection in the host. it has been proposed that regulatory t cell ... | 2016 | 27013348 |
| infectious disease and grouping patterns in mule deer. | infectious disease dynamics are determined, to a great extent, by the social structure of the host. we evaluated sociality, or the tendency to form groups, in rocky mountain mule deer (odocoileus hemionus hemionus) from a chronic wasting disease (cwd) endemic area in saskatchewan, canada, to better understand factors that may affect disease transmission. using group size data collected on 365 radio-collared mule deer (2008-2013), we built a generalized linear mixed model (glmm) to evaluate wheth ... | 2016 | 27007808 |
| aspects of the husbandry and management of captive cervids. | in a continuing effort to better understand the transmission and persistence of chronic wasting disease in wild populations of cervids, colorado state university, fort collins houses two species of deer indoors to study the pathogenesis of chronic wasting disease. here we report key aspects regarding the husbandry and medication of reeves' muntjac and white-tailed deer in captivity for research purposes. | 2016 | 27003353 |
| chronic wasting disease: transmission mechanisms and the possibility of harvest management. | we develop a model of cwd management by nonselective deer harvest, currently the most feasible approach available for managing cwd in wild populations. we use the model to explore the effects of 6 common harvest strategies on disease prevalence and to identify potential optimal harvest policies for reducing disease prevalence without population collapse. the model includes 4 deer categories (juveniles, adult females, younger adult males, older adult males) that may be harvested at different rate ... | 2016 | 26963921 |
| social affiliation and contact patterns among white-tailed deer in disparate landscapes: implications for disease transmission. | in social species, individuals contact members of the same group much more often than those of other groups, particularly for contacts that could directly transmit disease agents. this disparity in contact rates violates the assumptions of simple disease models, hinders disease spread between groups, and could decouple disease transmission from population density. social behavior of white-tailed deer has important implications for the long-term dynamics and impact of diseases such as bovine tube ... | 2015 | 26937044 |
| seeded amplification of chronic wasting disease prions in nasal brushings and recto-anal mucosa-associated lymphoid tissues from elk by real-time quaking-induced conversion. | chronic wasting disease (cwd), a transmissible spongiform encephalopathy of cervids, was first documented nearly 50 years ago in colorado and wyoming and has since been detected across north america and the republic of korea. the expansion of this disease makes the development of sensitive diagnostic assays and antemortem sampling techniques crucial for the mitigation of its spread; this is especially true in cases of relocation/reintroduction or prevalence studies of large or protected herds, w ... | 2016 | 26888899 |
| antemortem detection of chronic wasting disease prions in nasal brush collections and rectal biopsy specimens from white-tailed deer by real-time quaking-induced conversion. | chronic wasting disease (cwd), a transmissible spongiform encephalopathy of cervids, was first documented nearly 50 years ago in colorado and wyoming and has since spread to cervids in 23 states, two canadian provinces, and the republic of korea. the expansion of this disease makes the development of sensitive diagnostic assays and antemortem sampling techniques crucial for the mitigation of its spread; this is especially true in cases of relocation/reintroduction of farmed or free-ranging deer ... | 2016 | 26865693 |
| potential application of emerging diagnostic techniques to the diagnosis of bovine johne's disease (paratuberculosis). | mycobacterium avium subspecies paratuberculosis (map) causes johne's disease (paratuberculosis), a chronic wasting disease in cattle with important welfare, economic and potential public health implications. current tests are unable to recognise all stages of the disease, which makes it difficult to diagnose and control. this review explores emerging diagnostic techniques that could complement and enhance the diagnosis of map infection, including bacteriophage analysis, new map-specific antigens ... | 2016 | 26831164 |
| cross-species transmission of cwd prions. | prions cause fatal neurodegenerative diseases in humans and animals and can be transmitted zoonotically. chronic wasting disease (cwd) is a highly transmissible prion disease of wild deer and elk that affects cervids over extensive regions of the united states and canada. the risk of cross-species cwd transmission has been experimentally evaluated in a wide array of mammals, including non-human primates and mouse models expressing human cellular prion protein. here we review the determinants of ... | 2016 | 26809254 |
| peliosis hepatis presenting with massive hepatomegaly in a patient with idiopathic thrombocytopenic purpura. | peliosis hepatis is a rare condition that can cause hepatic hemorrhage, rupture, and ultimately liver failure. several authors have reported that peliosis hepatis develops in association with chronic wasting disease or prolonged use of anabolic steroids or oral contraceptives. in this report we describe a case in which discontinuation of steroid therapy improved the condition of a patient with peliosis hepatis. our patient was a 64-year-old woman with a history of long-term steroid treatment for ... | 2015 | 26770928 |
| cwd prions remain infectious after passage through the digestive system of coyotes (canis latrans). | chronic wasting disease (cwd) is a geographically expanding prion disease of wild and captive cervids in north america. disease can be transmitted directly, animal to animal, or indirectly via the environment. cwd contamination can occur residually in the environment via soil, water, and forage following deposition of bodily fluids such as urine, saliva, and feces, or by the decomposition of carcasses. recent work has indicated that plants may even take up prions into the stems and leaves. when ... | 2015 | 26636258 |
| prion protein gene sequence and chronic wasting disease susceptibility in white-tailed deer (odocoileus virginianus). | the sequence of the prion protein gene (prnp) affects susceptibility to spongiform encephalopathies, or prion diseases in many species. in white-tailed deer, both coding and non-coding single nucleotide polymorphisms have been identified in this gene that correlate to chronic wasting disease (cwd) susceptibility. previous studies examined individual nucleotide or amino acid mutations; here we examine all nucleotide polymorphisms and their combined effects on cwd. a 626 bp region of prnp was exam ... | 2015 | 26634768 |
| methods for differentiating prion types in food-producing animals. | prions are an enigma amongst infectious disease agents as they lack a genome yet confer specific pathologies thought to be dictated mainly, if not solely, by the conformation of the disease form of the prion protein (prp(sc)). prion diseases affect humans and animals, the latter including the food-producing ruminant species cattle, sheep, goats and deer. importantly, it has been shown that the disease agent of bovine spongiform encephalopathy (bse) is zoonotic, causing variant creutzfeldt jakob ... | 2015 | 26580664 |
| bayesian modeling of prion disease dynamics in mule deer using population monitoring and capture-recapture data. | epidemics of chronic wasting disease (cwd) of north american cervidae have potential to harm ecosystems and economies. we studied a migratory population of mule deer (odocoileus hemionus) affected by cwd for at least three decades using a bayesian framework to integrate matrix population and disease models with long-term monitoring data and detailed process-level studies. we hypothesized cwd prevalence would be stable or increase between two observation periods during the late 1990s and after 20 ... | 2015 | 26509806 |
| empirical estimation of r0 for unknown transmission functions: the case of chronic wasting disease in alberta. | we consider the problem of estimating the basic reproduction number r0 from data on prevalence dynamics at the beginning of a disease outbreak. we derive discrete and continuous time models, some coefficients of which are to be fitted from data. we show that prevalence of the disease is sufficient to determine r0. we apply this method to chronic wasting disease spread in alberta determining a range of possible r0 and their sensitivity to the probability of deer annual survival. | 2015 | 26452231 |
| magnetic microparticle-based multimer detection system for the detection of prion oligomers in sheep. | transmissible spongiform encephalopathies (tses) are zoonotic fatal neurodegenerative diseases in animals and humans. tses are commonly known as bovine spongiform encephalopathy in cattle, scrapie in sheep and goats, chronic wasting disease in cervids, and creutzfeldt-jakob disease in humans. the putative transmissible agents are infectious prion proteins (prp(sc)), which are formed by the conversion of the normal prion protein on the glycoprotein cell surface in the presence of other prp(sc). r ... | 2015 | 26425091 |
| deer prion proteins modulate the emergence and adaptation of chronic wasting disease strains. | transmission of chronic wasting disease (cwd) between cervids is influenced by the primary structure of the host cellular prion protein (prp(c)). in white-tailed deer, prnp alleles encode the polymorphisms q95 g96 (wild type [wt]), q95 s96 (referred to as the s96 allele), and h95 g96 (referred to as the h95 allele), which differentially impact cwd progression. we hypothesize that the transmission of cwd prions between deer expressing different allotypes of prp(c) modifies the contagious agent af ... | 2015 | 26423950 |
| in utero transmission and tissue distribution of chronic wasting disease-associated prions in free-ranging rocky mountain elk. | the presence of disease-associated prions in tissues and bodily fluids of chronic wasting disease (cwd)-infected cervids has received much investigation, yet little is known about mother-to-offspring transmission of cwd. our previous work demonstrated that mother-to-offspring transmission is efficient in an experimental setting. to address the question of relevance in a naturally exposed free-ranging population, we assessed maternal and fetal tissues derived from 19 elk dam-calf pairs collected ... | 2015 | 26358706 |
| age and repeated biopsy influence antemortem prp(cwd) testing in mule deer (odocoileus hemionus) in colorado, usa. | biopsy of rectal mucosa-associated lymphoid tissue provides a useful, but imperfect, live-animal test for chronic wasting disease (cwd) in mule deer (odocoileus hemionus). it is difficult and expensive to complete these tests on free-ranging animals, and wildlife health managers will benefit from methods that can accommodate test results of varying quality. to this end, we developed a hierarchical bayesian model to estimate the probability that an individual is infected based on test results. ou ... | 2015 | 26251986 |
| host determinants of prion strain diversity independent of prion protein genotype. | phenotypic diversity in prion diseases can be specified by prion strains in which biological traits are propagated through an epigenetic mechanism mediated by distinct prp(sc) conformations. we investigated the role of host-dependent factors on phenotypic diversity of chronic wasting disease (cwd) in different host species that express the same prion protein gene (prnp). two cwd strains that have distinct biological, biochemical, and pathological features were identified in transgenic mice that ... | 2015 | 26246570 |
| progressive accumulation of the abnormal conformer of the prion protein and spongiform encephalopathy in the obex of nonsymptomatic and symptomatic rocky mountain elk (cervus elaphus nelsoni) with chronic wasting disease. | the purpose of our study was to describe the progressive accumulation of the abnormal conformer of the prion protein (prp(cwd)) and spongiform degeneration in a single section of brain stem in rocky mountain elk (cervus elaphus nelsoni) with chronic wasting disease (cwd). a section of obex from 85 cwd-positive elk was scored using the presence and abundance of prp(cwd) immunoreactivity and spongiform degeneration in 10 nuclear regions and the presence and abundance of prp(cwd) in 10 axonal tract ... | 2015 | 26185123 |
| insights into chronic wasting disease and bovine spongiform encephalopathy species barriers by use of real-time conversion. | the propensity for transspecies prion transmission is related to the structural characteristics of the enciphering and new host prp, although the exact mechanism remains incompletely understood. the effects of variability in prion protein on cross-species prion transmission have been studied with animal bioassays, but the influence of prion protein structure versus that of host cofactors (e.g., cellular constituents, trafficking, and innate immune interactions) remains difficult to dissect. to i ... | 2015 | 26157118 |
| longitudinal detection of prion shedding in saliva and urine by chronic wasting disease-infected deer by real-time quaking-induced conversion. | chronic wasting disease (cwd) is an emergent, rapidly spreading prion disease of cervids. shedding of infectious prions in saliva and urine is thought to be an important factor in cwd transmission. to help to elucidate this issue, we applied an in vitro amplification assay to determine the onset, duration, and magnitude of prion shedding in longitudinally collected saliva and urine samples from cwd-exposed white-tailed deer. we detected prion shedding as early as 3 months after cwd exposure and ... | 2015 | 26136567 |
| transmission of scrapie prions to primate after an extended silent incubation period. | classical bovine spongiform encephalopathy (c-bse) is the only animal prion disease reputed to be zoonotic, causing variant creutzfeldt-jakob disease (vcjd) in humans and having guided protective measures for animal and human health against animal prion diseases. recently, partial transmissions to humanized mice showed that the zoonotic potential of scrapie might be similar to c-bse. we here report the direct transmission of a natural classical scrapie isolate to cynomolgus macaque, a highly rel ... | 2015 | 26123044 |
| use of a 2-aminothiazole to treat chronic wasting disease in transgenic mice. | treatment with the 2-aminothiazole ind24 extended the survival of mice infected with mouse-adapted scrapie but also resulted in the emergence of a drug-resistant prion strain. here, we determined whether ind24 extended the survival of transgenic mice infected with prions that caused scrapie in sheep or prions that caused chronic wasting disease (cwd; hereafter "cwd prions") in deer, using 2 isolates for each disease. ind24 doubled the incubation times for mice infected with cwd prions but had no ... | 2015 | 26116725 |
| genotyping of velvet antlers for identification of country of origin using mitochondrial dna and fluorescence melting curve analysis with locked nucleic acid probes. | velvet antlers are used medicinally in asia and possess various therapeutic effects. prices are set according to the country of origin, which is unidentifiable to the naked eye, and therefore counterfeiting is prevalent. additionally, antlers of the canadian elk, which can generate chronic wasting disease, are prevalently smuggled and distributed in the market. thus, a method for identifying the country of origin of velvet antlers was developed, using polymorphisms in mitochondrial dna, fluoresc ... | 2016 | 26094991 |
| molecular dynamics studies on the buffalo prion protein. | it was reported that buffalo is a low susceptibility species resisting to transmissible spongiform encephalopathies (tses) (same as rabbits, horses, and dogs). tses, also called prion diseases, are invariably fatal and highly infectious neurodegenerative diseases that affect a wide variety of species (except for rabbits, dogs, horses, and buffalo), manifesting as scrapie in sheep and goats; bovine spongiform encephalopathy (bse or "mad-cow" disease) in cattle; chronic wasting disease in deer and ... | 2016 | 26043781 |
| the transmissible spongiform encephalopathies of livestock. | prion diseases or transmissible spongiform encephalopathies (tses) are fatal protein-misfolding neurodegenerative diseases. tses have been described in several species, including bovine spongiform encephalopathy (bse) in cattle, scrapie in sheep and goats, chronic wasting disease (cwd) in cervids, transmissible mink encephalopathy (tme) in mink, and kuru and creutzfeldt-jakob disease (cjd) in humans. these diseases are associated with the accumulation of a protease-resistant, disease-associated ... | 2015 | 25991695 |
| grass plants bind, retain, uptake, and transport infectious prions. | prions are the protein-based infectious agents responsible for prion diseases. environmental prion contamination has been implicated in disease transmission. here, we analyzed the binding and retention of infectious prion protein (prp(sc)) to plants. small quantities of prp(sc) contained in diluted brain homogenate or in excretory materials (urine and feces) can bind to wheat grass roots and leaves. wild-type hamsters were efficiently infected by ingestion of prion-contaminated plants. the prion ... | 2015 | 25981035 |
| human prion protein sequence elements impede cross-species chronic wasting disease transmission. | | 2015 | 25961458 |
| animal models for prion-like diseases. | prion diseases or transmissible spongiform encephalopathies (tses) are a group of fatal neurodegenerative disorders affecting several mammalian species being creutzfeldt-jacob disease (cjd) the most representative in human beings, scrapie in ovine, bovine spongiform encephalopathy (bse) in bovine and chronic wasting disease (cwd) in cervids. as stated by the "protein-only hypothesis", the causal agent of tses is a self-propagating aberrant form of the prion protein (prp) that through a misfoldin ... | 2015 | 25907990 |
| circulation of prions within dust on a scrapie affected farm. | prion diseases are fatal neurological disorders that affect humans and animals. scrapie of sheep/goats and chronic wasting disease (cwd) of deer/elk are contagious prion diseases where environmental reservoirs have a direct link to the transmission of disease. using protein misfolding cyclic amplification we demonstrate that scrapie prp(sc) can be detected within circulating dusts that are present on a farm that is naturally contaminated with sheep scrapie. the presence of infectious scrapie wit ... | 2015 | 25889731 |
| assessing transmissible spongiform encephalopathy species barriers with an in vitro prion protein conversion assay. | studies to understanding interspecies transmission of transmissible spongiform encephalopathies (tses, prion diseases) are challenging in that they typically rely upon lengthy and costly in vivo animal challenge studies. a number of in vitro assays have been developed to aid in measuring prion species barriers, thereby reducing animal use and providing quicker results than animal bioassays. here, we present the protocol for a rapid in vitro prion conversion assay called the conversion efficiency ... | 2015 | 25867521 |
| aggregation and environmental transmission in chronic wasting disease. | disease transmission depends on the interplay between the infectious agent and the behavior of the host. some diseases, such as chronic wasting disease, can be transmitted directly between hosts as well as indirectly via the environment. the social behavior of hosts affects both of these pathways, and a successful intervention requires knowledge of the relative influence of the different etiological and behavioral aspects of the disease. we develop a strategic differential equation model for chr ... | 2015 | 25811337 |
| first detection of macrorhabdus ornithogaster in wild eurasian siskins (carduelis spinus) in germany. a case study. | the colonization of the gastric ascomycetous yeast macrorhabdus (m.) ornithogaster could be associated with a chronic wasting disease in several bird species in captivity. the prevalence and clinical relevance of m. ornithogaster in wild birds is unknown in detail. | 2015 | 25804259 |
| human prion protein sequence elements impede cross-species chronic wasting disease transmission. | chronic wasting disease (cwd) is a fatal prion disease of north american deer and elk and poses an unclear risk for transmission to humans. human exposure to cwd occurs through hunting activities and consumption of venison from prion-infected animals. although the amino acid residues of the prion protein (prp) that prevent or permit human cwd infection are unknown, nmr-based structural studies suggest that the β2-α2 loop (residues 165-175) may impact species barriers. here we sought to define pr ... | 2015 | 25705888 |
| metals in obex and retropharyngeal lymph nodes of illinois white-tailed deer and their variations associated with cwd status. | prion proteins (prp(c)) are cell membrane glycoproteins that can be found in many cell types, but specially in neurons. many studies have suggested prp(c)'s participation in metal transport and cellular protection against stress in the central nervous system (cns). on the other hand prp(sc), the misfolded isoform of prp(c) and the pathogenic agent in transmissible spongiform encephalopathies (tse), has been associated with brain metal dyshomeostasis in prion diseases. thus, changes in metal conc ... | 2015 | 25695915 |
| experimental infection of meadow voles (microtus pennsylvanicus) with sheep scrapie. | meadow voles (microtus pennsylvanicus) are permissive to chronic wasting disease (cwd) infection, but their susceptibility to other transmissible spongiform encephalopathies (tses) is poorly characterized. in this initial study, we intracerebrally challenged 6 meadow voles with 2 isolates of sheep scrapie. three meadow voles acquired a tse after the scrapie challenge and an extended incubation period. the glycoform profile of proteinase k-resistant prion protein (prp(res)) in scrapie-sick voles ... | 2015 | 25673912 |
| prion amplification and hierarchical bayesian modeling refine detection of prion infection. | prions are unique infectious agents that replicate without a genome and cause neurodegenerative diseases that include chronic wasting disease (cwd) of cervids. immunohistochemistry (ihc) is currently considered the gold standard for diagnosis of a prion infection but may be insensitive to early or sub-clinical cwd that are important to understanding cwd transmission and ecology. we assessed the potential of serial protein misfolding cyclic amplification (spmca) to improve detection of cwd prior ... | 2015 | 25665713 |
| mitigation of prion infectivity and conversion capacity by a simulated natural process--repeated cycles of drying and wetting. | prions enter the environment from infected hosts, bind to a wide range of soil and soil minerals, and remain highly infectious. environmental sources of prions almost certainly contribute to the transmission of chronic wasting disease in cervids and scrapie in sheep and goats. while much is known about the introduction of prions into the environment and their interaction with soil, relatively little is known about prion degradation and inactivation by natural environmental processes. in this stu ... | 2015 | 25665187 |
| generation of a persistently infected mdbk cell line with natural bovine spongiform encephalopathy (bse). | bovine spongiform encephalopathy (bse) is a zoonotic transmissible spongiform encephalopathy (tse) thought to be caused by the same prion strain as variant creutzfeldt-jakob disease (vcjd). unlike scrapie and chronic wasting disease there is no cell culture model allowing the replication of proteinase k resistant bse (prpbse) and the further in vitro study of this disease. we have generated a cell line based on the madin-darby bovine kidney (mdbk) cell line over-expressing the bovine prion prote ... | 2015 | 25647616 |
| efficient, validated method for detection of mycobacterial growth in liquid culture media by use of bead beating, magnetic-particle-based nucleic acid isolation, and quantitative pcr. | pathogenic mycobacteria are difficult to culture, requiring specialized media and a long incubation time, and have complex and exceedingly robust cell walls. mycobacterium avium subsp. paratuberculosis (map), the causative agent of johne's disease, a chronic wasting disease of ruminants, is a typical example. culture of map from the feces and intestinal tissues is a commonly used test for confirmation of infection. liquid medium offers greater sensitivity than solid medium for detection of map; ... | 2015 | 25609725 |
| mucosal immunization with an attenuated salmonella vaccine partially protects white-tailed deer from chronic wasting disease. | prion disease is a unique category of illness, affecting both animals and humans, in which the underlying pathogenesis is related to a conformational change of a normal, self-protein called prp(c) (c for cellular) to a pathological and infectious conformer known as prp(sc) (sc for scrapie). bovine spongiform encephalopathy (bse), a prion disease believed to have arisen from feeding cattle with prion contaminated meat and bone meal products, crossed the species barrier to infect humans. chronic w ... | 2015 | 25539804 |
| in vitro amplification of scrapie and chronic wasting disease prp(res) using baculovirus-expressed recombinant prp as substrate. | protein misfolding cyclic amplification (pmca) is an in vitro simulation of prion replication, which relies on the use of normal brain homogenate derived from host species as substrate for the specific amplification of abnormal prion protein, prp(sc). studies showed that recombinant cellular prp, prp(c), expressed in escherichia coli lacks n-glycosylation and an glycophosphatidyl inositol anchor (gpi) and therefore may not be the most suitable substrate in seeded pmca reactions to recapitulate p ... | 2014 | 25495764 |
| multimodal fluorescence microscopy of prion strain specific prp deposits stained by thiophene-based amyloid ligands. | the disease-associated prion protein (prp) forms aggregates which vary in structural conformation yet share an identical primary sequence. these variations in prp conformation are believed to manifest in prion strains exhibiting distinctly different periods of disease incubation as well as regionally specific aggregate deposition within the brain. the anionic luminescent conjugated polythiophene (lcp), polythiophene acetic acid (ptaa) has previously been used to distinguish prp deposits associat ... | 2014 | 25495506 |
| variant cjd. 18 years of research and surveillance. | it is now 18 years since the first identification of a case of vcjd in the uk. since that time, there has been much speculation over how vcjd might impact human health. to date there have been 177 case reports in the uk and a further 51 cases worldwide in 11 different countries. since establishing that bse and vcjd are of the same strain of agent, we have also shown that there is broad similarity between uk and non-uk vcjd cases on first passage to mice. transgenic mouse studies have indicated t ... | 2014 | 25495404 |
| chronic wasting disease of cervids: current knowledge and future perspectives. | a naturally occurring transmissible spongiform encephalopathy (tse) of mule deer was first reported in colorado and wyoming in 1967 and has since spread to other members of the cervid family in 22 states, 2 canadian provinces, and the republic of korea. chronic wasting disease (cwd), caused by exposure to an abnormally folded isoform of the cellular prion protein, is characterized by progressive neurological disease in susceptible natural and experimental hosts and is ultimately fatal. cwd is th ... | 2015 | 25387112 |
| a survey and a molecular dynamics study on the (central) hydrophobic region of prion proteins. | prion diseases which are serious neurodegenerative diseases that affect humans and animals occur in various of species. unlike many other neurodegenerative diseases affected by amyloid, prion diseases can be highly infectious. prion diseases occur in many species. in humans, prion diseases include the fatal human neurodegenerative diseases such as creutzfeldt-jakob disease (cjd), fatal familial insomnia (ffi), gerstmann-strussler-scheinker syndrome (gss) and kuru etc. in animals, prion diseases ... | 2014 | 25373387 |
| persistence of ovine scrapie infectivity in a farm environment following cleaning and decontamination. | scrapie of sheep/goats and chronic wasting disease of deer/elk are contagious prion diseases where environmental reservoirs are directly implicated in the transmission of disease. in this study, the effectiveness of recommended scrapie farm decontamination regimens was evaluated by a sheep bioassay using buildings naturally contaminated with scrapie. pens within a farm building were treated with either 20,000 parts per million free chorine solution for one hour or were treated with the same but ... | 2015 | 25362003 |
| quantitative assessment of prion infectivity in tissues and body fluids by real-time quaking-induced conversion. | prions are amyloid-forming proteins that cause transmissible spongiform encephalopathies through a process involving the templated conversion of the normal cellular prion protein (prp(c)) to a pathogenic misfolded conformation. templated conversion has been modelled in several in vitro assays, including serial protein misfolding amplification, amyloid seeding and real-time quaking-induced conversion (rt-quic). as rt-quic measures formation of amyloid fibrils in real-time, it can be used to estim ... | 2015 | 25304654 |
| sero-diagnosis of surra exploiting recombinant vsg antigen based elisa for surveillance. | trypanosoma evansi, a haemoflagellate, causes "surra" an important chronic wasting disease of a wide range of wild and domestic herbivorous and carnivorous animals including cattle, buffaloes, camels, horses, etc. the untreated recovered animal can act as a carrier without exhibiting the disease symptoms and can be a source of infection to healthy animals. the diagnosis and subsequent treatment of the carrier animals is helpful to curb the disease. as the parasitaemia in carrier animals is very ... | 2014 | 25269987 |
| six-year follow-up of a point-source exposure to cwd contaminated venison in an upstate new york community: risk behaviours and health outcomes 2005-2011. | it is currently unknown whether chronic wasting disease (cwd), a transmissible spongiform encephalopathy of cervids, is transmissible to humans. reported on here are the behavioural risk factors and health conditions associated with a six-year follow-up of a known point-source exposure to a cwd infected deer in an upstate new york community. | 2014 | 25225155 |
| structural effects of prp polymorphisms on intra- and interspecies prion transmission. | understanding the molecular parameters governing prion propagation is crucial for controlling these lethal, proteinaceous, and infectious neurodegenerative diseases. to explore the effects of prion protein (prp) sequence and structural variations on intra- and interspecies transmission, we integrated studies in deer, a species naturally susceptible to chronic wasting disease (cwd), a burgeoning, contagious epidemic of uncertain origin and zoonotic potential, with structural and transgenic (tg) m ... | 2014 | 25034251 |
| detection of chronic wasting disease in the lymph nodes of free-ranging cervids by real-time quaking-induced conversion. | chronic wasting disease (cwd), a transmissible spongiform encephalopathy of deer, elk, and moose, is the only prion disease affecting free-ranging animals. since the disease was first identified in northern colorado and southern wyoming in 1967, new epidemic foci of the disease have been identified in 20 additional states, as well as two canadian provinces and the republic of south korea. identification of cwd-affected animals currently requires postmortem analysis of brain or lymphoid tissues u ... | 2014 | 24958799 |
| prion protein interaction with soil humic substances: environmental implications. | transmissible spongiform encephalopathies (tse) are fatal neurodegenerative disorders caused by prions. animal tse include scrapie in sheep and goats, and chronic wasting disease (cwd) in cervids. effective management of scrapie in many parts of the world, and of cwd in north american deer population is complicated by the persistence of prions in the environment. after shedding from diseased animals, prions persist in soil, withstanding biotic and abiotic degradation. as soil is a complex, multi ... | 2014 | 24937266 |
| distribution of peripheral prp(sc) in sheep with naturally acquired scrapie. | accumulation of prion protein (prpsc) in the central nervous system is the hallmark of transmissible spongiform encephalopathies. however, in some of these diseases such as scrapie or chronic wasting disease, the prpsc can also accumulate in other tissues, particularly in the lymphoreticular system. in recent years, prpsc in organs other than nervous and lymphoid have been described, suggesting that distribution of this protein in affected individuals may be much larger than previously thought. ... | 2014 | 24828439 |
| "atypical" chronic wasting disease in prnp genotype 225ff mule deer. | we compared mule deer (odocoileus hemionus) of two different prnp genotypes (225ss, 225ff) for susceptibility to chronic wasting disease (cwd) in the face of environmental exposure to infectivity. all three 225ss deer had immunohistochemistry (ihc)-positive tonsil biopsies by 710 days postexposure (dpe), developed classic clinical signs by 723-1,200 dpe, and showed gross and microscopic pathology, enzyme-linked immunosorbent assay (elisa) results, and ihc staining typical of prion disease in mul ... | 2014 | 24807352 |
| swainsonine-containing plants and their relationship to endophytic fungi. | swainsonine, an indolizidine alkaloid with significant physiological activity, is an α-mannosidase and mannosidase ii inhibitor that alters glycoprotein processing and causes lysosomal storage disease. swainsonine is present in a number of plant species worldwide and causes severe toxicosis in livestock grazing these plants. consumption of these plants by grazing animals leads to a chronic wasting disease characterized by weight loss, depression, altered behavior, decreased libido, infertility, ... | 2014 | 24758700 |
| chronic wasting disease agents in nonhuman primates. | chronic wasting disease is a prion disease of cervids. assessment of its zoonotic potential is critical. to evaluate primate susceptibility, we tested monkeys from 2 genera. we found that 100% of intracerebrally inoculated and 92% of orally inoculated squirrel monkeys were susceptible, but cynomolgus macaques were not, suggesting possible low risk for humans. | 2014 | 24751215 |
| quinacrine promotes replication and conformational mutation of chronic wasting disease prions. | quinacrine's ability to reduce levels of pathogenic prion protein (prp(sc)) in mouse cells infected with experimentally adapted prions led to several unsuccessful clinical studies in patients with prion diseases, a 10-y investment to understand its mechanism of action, and the production of related compounds with expectations of greater efficacy. we show here, in stark contrast to this reported inhibitory effect, that quinacrine enhances deer and elk prp(sc) accumulation and promotes propagation ... | 2014 | 24711410 |
| mineral licks: motivational factors for visitation and accompanying disease risk at communal use sites of elk and deer. | free-ranging cervids acquire most of their essential minerals through forage consumption, though occasionally seek other sources to account for seasonal mineral deficiencies. mineral sources occur as natural geological deposits (i.e., licks) or as anthropogenic mineral supplements. in both scenarios, these sources commonly serve as focal sites for visitation. we monitored 11 licks in rocky mountain national park, north-central colorado, using trail cameras to quantify daily visitation indices (d ... | 2014 | 24711146 |
| evidence that bank vole prp is a universal acceptor for prions. | bank voles are uniquely susceptible to a wide range of prion strains isolated from many different species. to determine if this enhanced susceptibility to interspecies prion transmission is encoded within the sequence of the bank vole prion protein (bvprp), we inoculated tg(m109) and tg(i109) mice, which express bvprp containing either methionine or isoleucine at polymorphic codon 109, with 16 prion isolates from 8 different species: humans, cattle, elk, sheep, guinea pigs, hamsters, mice, and m ... | 2014 | 24699458 |
| using auxiliary information to improve wildlife disease surveillance when infected animals are not detected: a bayesian approach. | there are numerous situations in which it is important to determine whether a particular disease of interest is present in a free-ranging wildlife population. however adequate disease surveillance can be labor-intensive and expensive and thus there is substantial motivation to conduct it as efficiently as possible. surveillance is often based on the assumption of a simple random sample, but this can almost always be improved upon if there is auxiliary information available about disease risk fac ... | 2014 | 24676479 |
| transmission of chronic wasting disease in wisconsin white-tailed deer: implications for disease spread and management. | few studies have evaluated the rate of infection or mode of transmission for wildlife diseases, and the implications of alternative management strategies. we used hunter harvest data from 2002 to 2013 to investigate chronic wasting disease (cwd) infection rate and transmission modes, and address how alternative management approaches affect disease dynamics in a wisconsin white-tailed deer population. uncertainty regarding demographic impacts of cwd on cervid populations, human and domestic anima ... | 2014 | 24658535 |
| potential role of soil properties in the spread of cwd in western canada. | chronic wasting disease (cwd) is a horizontally transmissible prion disease of free ranging deer, elk and moose. recent experimental transmission studies indicate caribou are also susceptible to the disease. cwd is present in southeast alberta and southern saskatchewan. this cwd-endemic region is expanding, threatening manitoba and areas of northern alberta and saskatchewan, home to caribou. soil can serve as a stable reservoir for infectious prion proteins; prions bound to soil particles remain ... | 2016 | 24618673 |
| lesion profiling and subcellular prion localization of cervid chronic wasting disease in domestic cats. | chronic wasting disease (cwd) is an efficiently transmitted, fatal, and progressive prion disease of cervids with an as yet to be fully clarified host range. while outbred domestic cats (felis catus) have recently been shown to be susceptible to experimental cwd infection, the neuropathologic features of the infection are lacking. such information is vital to provide diagnostic power in the event of natural interspecies transmission and insights into host and strain interactions in interspecies ... | 2015 | 24577721 |
| exploring the zoonotic potential of animal prion diseases: in vivo and in vitro approaches. | following the discovery of a causal link between bovine spongiform encephalopathy (bse) in cattle and variant creutzfeldt-jakob disease (vcjd) in humans, several experimental approaches have been used to try to assess the potential risk of transmission of other animal transmissible spongiform encephalopathies (tses) to humans. experimental challenge of non-human primates, humanised transgenic mice and cell-free conversion systems have all been used as models to explore the susceptibility of huma ... | 2016 | 24549113 |
| can plants serve as a vector for prions causing chronic wasting disease? | prions, the causative agent of chronic wasting disease (cwd) enter the environment through shedding of bodily fluids and carcass decay, posing a disease risk as a result of their environmental persistence. plants have the ability to take up large organic particles, including whole proteins, and microbes. this study used wheat (triticum aestivum l.) to investigate the uptake of infectious cwd prions into roots and their transport into aerial tissues. the roots of intact wheat plants were exposed ... | 2014 | 24509640 |