hungary remains free of scrapie and bovine spongiform encephalopathy (bse).brains from 44 sheep and 43 cattle with cns clinical signs not due to rabies virus infection were collected from diagnostic institutes throughout hungary. the brains were examined for histological lesions diagnostic of scrapie/bovine spongiform encephalopathy (bse) and all were found to be negative. these findings confirm that hungary remains free of scrapie and bse.19938017235
western blot mapping of disease-specific amyloid in various animal species and humans with transmissible spongiform encephalopathies using a high-yield purification method.saf-protein, an amyloid, is the main constituent of scrapie-associated fibrils (saf) and a specific marker for transmissible spongiform encephalopathies (tse). using an improved extraction method and western blot detection, the disease-specific amyloid was found in various parts of the central nervous system of hamsters orally infected with scrapie, of squirrel monkeys orally infected with kuru, sporadic creutzfeldt-jakob disease (cjd) and scrapie, of human patients with sporadic cjd, of a sheep ...19957595360
beef and bovine spongiform encephalopathy: the risk persists.bovine spongiform encephalopathy (bse) is one of the transmissible spongiform encephalopathies (tse) that are currently known to the authors to affect only mammals, including man. the diseases are progressive, fatal paralyses and dementias, for which there are no methods of certain diagnosis and no treatment. in this review the disease in cattle, the mode of transfer of these tses between animals by mouth, the possible presence of infective agents in the food that we eat, the resistance of bse t ...19911923069
origin of bse. 19958693682
[prion diseases. review of the literature on the light of two case reports of creutzfeldt-jakob disease].during the last ten years the diseases scrapie in sheep and bovine spongiform encephalopathy (or mad cow disease) in cattle have received increased attention. through the 1960s it became apparent that scrapie in sheep and kuru and later creutzfeldt-jakob disease in man were infectious diseases. during the last decade the appearance of mad cow disease in great britain has increased the fear that humans can develop creutzfeldt-jakob disease through their food. a special characteristic of the infec ...19968658476
human prion diseases.the term 'prion diseases' refers to a group of neurodegenerative disorders thought to be caused by prions, pathogenic agents with novel modes of replication and transmission. prion diseases are characterized by long incubation periods ranging from months to years and are invariably fatal once clinical symptoms have appeared. they are also called transmissible spongiform encephalopathies (tse), on account of the predominant neuropathological change observed in the central nervous system. the most ...200011087170
link between scrapie and bse? 19902366871
transmissible spongiform encephalopathies (tse): minimizing the risk of transmission by biological/biopharmaceutical products: an industry perspective.several guidelines and recommendations have been published on assessing the potential risk of a biological product being contaminated with an agent causing a transmissible spongiform encephalopathy (tse). basic principles which can be used during the manufacturing of biological products to minimize the risk of transmission of tse agents include the following: (i) obtaining animals, tissues or animal-derived raw materials from countries in which the relevant tse agent is reported to be absent; (i ...19969119148
protease-resistant prp deposition in brain and non-central nervous system tissues of a murine model of bovine spongiform encephalopathy.infectivity within the central nervous system has been demonstrated by the transmission of bovine spongiform encephalopathy (bse) from affected cattle to inbred laboratory mice. sedimentable, protease-resistant prp (prpsc) has also been extracted from bse-affected cattle brain. both infectivity and prpsc have been reported in the lymphoreticular tissues of sheep and mice clinically and preclinically affected with scrapie. neither infectivity nor prpsc has yet been detected in non-neural tissues ...19968760446
strain specific and common pathogenic events in murine models of scrapie and bovine spongiform encephalopathy.the development of transmissible spongiform encephalopathies in experimental models depends on two major factors: the intracerebral accumulation of an abnormal, protease-resistant isoform of prp (prpres), which is a host protein mainly expressed in neurons; and the existence of different strains of agent. in order to make a distinction between pathogenic mechanisms depending upon the accumulation of host-derived prpres and the strain-specific effects, we quantified and compared the sequence of m ...19968758005
infectious diseases. is bse in sheep a no-brainer? 200111679649
ecosystems supporting clusters of sporadic tses demonstrate excesses of the radical-generating divalent cation manganese and deficiencies of antioxidant co factors cu, se, fe, zn. does a foreign cation substitution at prion protein's cu domain initiate tse?analyses of food chains supporting isolated clusters of sporadic tses (cwd in n colorado, scrapie in iceland, cjd in slovakia) demonstrate a consistent 2 1/2+ fold greater concentration of the pro-oxidant divalent cation, manganese (mn), in relation to normal levels recorded in adjoining tse-free localities. deficiencies of the antioxidant co factors cu/se/zn/fe and mg, p and na were also consistently recorded in tse foodchains. similarities between the clinical/pathological profile of tses and ...200010790765
bovine spongiform encephalopathy: a neuropathological perspective.the occurrence of bovine spongiform encephalopathy (bse), recognition that it is a new scrapie-like disease epidemic in domestic cattle in the united kingdom and concern of a remote zoonotic potential has, in four years, produced a plethora of documented information. while much of this information has been communicated outwith the scientific literature, this review attempts to summarise, from a neuropathological viewpoint, the main findings to emerge. the initial studies established the nosologi ...19911688299
risk of transmission of bovine spongiform encephalopathy to humans in the united states: report of the council on scientific affairs. american medical association.the risk of possible transmission of bovine spongiform encephalopathy (bse) in the united states is a substantial public health concern.199910386559
[bse and creutzfeldt-jakob disease. implication on health politics in germany and europe]. 200211845391
review blames bse outbreak on calf feed. 200111484009
synthetic peptide vaccines yield monoclonal antibodies to cellular and pathological prion proteins of ruminants.transmissible spongiform encephalopathies are closely linked to the accumulation of a pathological isoform of a host-encoded prion protein (prp(c)), designated prp(sc). in an attempt to generate mono- and polyclonal antibodies to ruminant prp, 32 mice were vaccinated with peptide vaccines which were synthesized according to the amino acid sequence of ovine prp. by this approach five prp-reactive polyclonal antisera directed against four different domains of the protein were stimulated. splenocyt ...19989568991
studies on a species-specific epitope in murine, ovine and bovine prion protein.transmissible spongiform encephalopathies are fatal neurodegenerative disorders which are linked to abnormal isoforms of the prion protein (prp), which is expressed in different cells of various mammalian species. susceptibility to disease and reduced transmission rates upon the first passage to another species are thought to be a result of functional and biochemical differences of the prp as a consequence of amino acid sequence among species. in 1985 an epidemic of bovine spongiform encephalopa ...19937687651
autoantibodies to brain components and antibodies to acinetobacter calcoaceticus are present in bovine spongiform encephalopathy.bovine spongiform encephalopathy (bse) is a neurological disorder, predominantly of british cattle, which belongs to the group of transmissible spongiform encephalopathies together with creutzfeldt-jakob disease (cjd), kuru, and scrapie. autoantibodies to brain neurofilaments have been previously described in patients with cjd and kuru and in sheep affected by scrapie. spongiform-like changes have also been observed in chronic experimental allergic encephalomyelitis, at least in rabbits and guin ...199910569779
bovine spongiform encephalopathy (bse): a stimulus to wider research.the severity of the epidemic of bovine spongiform encephalopathy which is currently afflicting cattle in the british isles has stimulated a considerable research effort, much of which is directed toward understanding the aetiology and pathogenesis of the bovine disease. however, a significant thrust has also been orchestrated to address more fundamental issues such as the nature of the uncharacterized causal agents of the wider range of unusual animal and human diseases which share similar chara ...19921364085
validation of a luminescence immunoassay for the detection of prp(sc) in brain homogenate.a luminescence immunoassay (lia) was developed for the diagnosis of bovine spongiform encephalopathy (bse) in brain tissue using two different monoclonal antibodies for capture and detection of the protease-resistant fragment of the pathological prion protein (prp27-30). prp27-30 currently represents the most reliable marker for the infectious particle (denominated prion) causing transmissible spongiform encephalopathies (tses). internal and official validation studies of this assay are describe ...200211849686
[prion diseases and a new variant of creutzfeldt-jakob disease].the causal link of a new variant of cjd (v-cjd) with bovine spongiform encephalopathy (bse) has led to world-wide panic. bse emerged in 1986 through dietary products contaminated with scrapie pathogen, bse case reports increased in number up to 37,000/year in 1993, then declined in 1994 when the first case of v-cjd emerged. there is a 3-year gap between the emergence of bse and the introduction of a ban on the use of specified bovine offal in human food. people might have consumed dietary produc ...19969128415
brussels reshapes science panels after bse criticism. 19979194548
bovine spongiform encephalopathy (bse) and its epidemiology.since the recognition of bse in 1986, over 180,000 cattle in the uk have developed the disease and 1-3 million are likely to have been infected with the bse agent, most of which were slaughtered for human consumption before developing signs of the disease. the origin of the first case of bse is unknown, but the epidemic was caused by the recycling of processed waste parts of cattle, some of which were infected with the bse agent, to other cattle in feed. control measures have resulted in the con ...200314522859
[consequences of bse/tse for the clinical diagnostic in cattle and sheep].the first case of bovine spongiform encephalopathy (bse) in germany induced a profound irritation not only of the consumers but also of the farmers and the veterinarians in germany. the following bse-crisis accelerated the structural changes in beef and dairy industries. the analysis of the detected bse-cases of the last years in germany and switzerland shows that the sensitivity of bse-tests is much higher in clinically preselected bse-suspected cases compared to bse-tests in normal slaughter c ...200212224461
proteinase k enhanced immunoreactivity of the prion protein-specific monoclonal antibody, we report the development and further characterisation of a novel prp-specific monoclonal antibody: 2a11. by western blot analysis, 2a11 reacts with prpc from a variety of species including cow, sheep, pig, hamster, rabbit, cat, dog, deer and mouse but fails to react with human, chicken and turtle prp. reactivity to prpc in western blot was found to be dependent on the redox state of the protein since binding of mab 2a11 to its epitope was more effective in reducing conditions. 2a11 bindin ...200414687883
bse awareness programme in tasmania. 19948059517
bse: can we predict the future?prion diseases are transmissible neurodegenerative disorders of humans and animals. the prion protein (prpc) gene is expressed to some extent in many cell types but principally in neurons. normal prpc may contribute in the protection of neurons and are protease sensitive. abnormal prions consist of a post-translationally modified form of prp, prpsc, which is partly protease resistant. prpsc is a protein with high resistance to inactivation by irradiation, heat and harsh chemical treatments. it i ...19979581370
molecular analysis of ovine prion protein identifies similarities between bse and an experimental isolate of natural scrapie, variant creutzfeldt-jakob disease (vcjd) and bovine spongiform encephalopathy (bse) are caused by the same strain of pathogen and, as sheep can develop experimental bse, this has raised concern that humans may be at risk from eating mutton if bse has naturally transmitted to sheep. biochemical typing of abnormal prion proteins (prpsc) has been suggested to detect bse in sheep. although this approach is ingenuous, we can now report biochemical evidence of strain variation in contemporary and ...19999934675
the transmissible spongiform encephalopathies: disease risks for north america.transmissible spongiform encephalopathies exotic to north america (bse and associated diseases) are unlikely to be introduced or to persist should they be introduced into the united states [2]. domestic tses (scrapie, cwd, and tme) seem to be relatively restricted in their host range, and none of these diseases is known to naturally cause disease in cattle. it is important that surveillance for tses continues, however, particularly in cattle because of the extreme consequences to the livestock i ...200212442578
inactivation of se agents.the transmissible agents of the spongiform encephalopathies are relatively resistant to inactivation, and accidental transmission has occurred in animals and man. rigorous chemical or physical procedures are required to achieve decontamination, and their effectiveness can only be determined by bioassay in animals. the best-defined model is scrapie in mice or hamsters, and this has been used in many of the studies to establish practical inactivation procedures. although a number of techniques had ...19938137130
the first canadian indigenous case of bovine spongiform encephalopathy (bse) has molecular characteristics for prion protein that are similar to those of bse in the united kingdom but differ from those of chronic wasting disease in captive elk and deer.brain tissue from a case of bovine spongiform encephalopathy (bse) from alberta was subjected to a western immunoblotting technique to ascertain the molecular profile of any disease-specific, abnormal prion protein, that is, prion protein that is protease-resistant (prp(res)). this technique can discriminate between isolates from bse, ovine scrapie, and sheep experimentally infected with bse. isolates of brain tissue from the bse case in alberta, 3 farmed elk with chronic wasting disease (cwd) f ...200415532881
the shifting biology of prions.transmissible spongiform encephalopathies (tses), or prion diseases, are rare fatal neurodegenerative diseases of humans and animals. although some tses, like scrapie in sheep, have been known to exist for centuries, bovine spongiform encephalopathy (bse) was recognized only 15 years ago. new variant creutzfeldt-jakob disease (nvcjd) of humans is probably caused by consumption of bse-infected materials. the nature of the infectious agent is not fully elucidated, but substantial evidence suggests ...200111690621
scrapie strains maintain biological phenotypes on propagation in a cell line in culture.bovine spongiform encephalopathy (bse) and its human equivalent, variant creutzfeldt-jakob disease (vcjd), are caused by the same strain of infectious agent, which is similar to, but distinct from, >20 strains of their sheep scrapie homologue. a better understanding of the molecular strain determinants could be obtained from cells in monoculture than from whole animal studies where different cell targeting is commonly a strain-related feature. although a few cell types can be infected with diffe ...200111432823
application of prionics western blotting procedure to screen for bse in cattle regularly slaughtered at swiss abattoirs.disease-specific prp (prp(sc)) is at least part of the infectious particle (prion) causing bovine spongiform encephalopathy (bse) or scrapie in sheep. digestion with protease allows a distinction between normal prp (prp(c)) and prp(sc) i.e. prp(c) is completely digested while prp(sc) is cleaved at the n-terminus leading to a fragment of reduced molecular weight (prp 27-30). detection of this fragment by western blotting has been described more than a decade ago for rodent prp. we have now optimi ...200011214922
bse record set straight. 200111713498
experimentally induced bovine spongiform encephalopathy did not transmit via goat embryos.goats are susceptible to experimental challenge with bovine spongiform encephalopathy (bse). this study set out to investigate whether the transmission of bse could occur in goats following the transfer of embryos from experimentally infected donor females into uninfected recipient females. the results showed no evidence of transmissible spongiform encephalopathy disease in any of the offspring which developed from embryos from infected donors, nor indeed in any of the recipient females used as ...199910073715
characterization of bse and scrapie strains/isolates.following the bse epidemic in cattle and the emergence of a variant form of creutzfeldt-jakob disease in humans, the question was raised whether bse has been transmitted to small ruminants by the inadvertent feeding of infectious meat and bone meal. such infections could easily be concealed in countries where scrapie is endemic. to address this issue by immuno-chemically analyzing the prp(sc) fragments, we have developed two lines of research. firstly we have focused on the development of criter ...200011214925
risk management of the transmissible spongiform encephalopathies in north north american free trade agreement partners, canada, the united states of america (usa) and mexico apply independent but harmonised transmissible spongiform encephalopathy (tse) risk management strategies in observance of office international des epizooties guidelines. the divergence between bovine spongiform encephalopathy (bse) risk management approaches in north american and europe reflects comparatively reduced external and internal bse risks in north america. the external quarantine and ...200312793780
is mad cow disease caused by a bacteria?transmissible spongioform enchephalopathies (tse's), include bovine spongiform encephalopathy (also called bse or "mad cow disease"), creutzfeldt-jakob disease (cjd) in humans, and scrapie in sheep. they remain a mystery, their cause hotly debated. but between 1994 and 1996, 12 people in england came down with cjd, the human form of mad cow, and all had eaten beef from suspect cows. current mad cow diagnosis lies solely in the detection of late appearing "prions", an acronym for hypothesized, ge ...200415325025
epidemiological implications of the susceptibility to bse of putatively resistant sheep.the experimental infection of sheep with bovine spongiform encephalopathy (bse) by the oral route and the likelihood that sheep were fed bse-infected meat and bone meal has led to extensive speculation as to whether or not sheep are naturally infected with bse. in response, the uk government has initiated the national scrapie plan (nsp), an ambitious pound 120 million per year project to create a bse- and scrapie-resistant national sheep flock, by selectively breeding for a genotype of sheep bel ...200314645932
analysis of polymorphic microsatellites within the bovine and ovine prion protein (prnp) genes.twenty-four microsatellite sites with at least three repeats were found in the bovine prion protein gene (prnp) and 23 in the ovine prnp gene. eight microsatellite sites were polymorphic in cattle and six in sheep with up to 10 alleles per site. in many cases allelic dna fragments had variants in microsatellite sites and in flanking regions. distances between microsatellite sites in eight genes from cattle and sheep occurred on average every 0.9 kb. the numerous polymorphic microsatellite sites ...200312873216
australian response to bse. 200011225536
bovine spongiform encephalopathy (bse) in sheep? 200212019700
the role of prp in health and disease.transmissible spongiform encephalopathies (tses) such as scrapie in sheep, bovine spongiform encephalopathy (bse) in cattle or creutzfeldt-jacob disease (cjd) and gerstmann-sträussler-scheinker syndrome (gss) in humans, are caused by an infectious agent designated prion. the "protein only" hypothesis states that the prion consists partly or entirely of a conformational isoform of the normal host protein prpc and that the abnormal conformer, when introduced into the organism, causes the conversio ...200415354865
rare breeds and the bse situation. 19968730680
[study on bovine spongiform encephacitis and current status of safety control of medical devices deriving from animals].to introduce the basic information about mad cow disease and the current status of safety control of medical devices derived from mammalian animal tissues.200617191585
bse: a consequence of cattle feeding with glycated molecules host-unknown?although there is much evidence supporting a prion contribution in the pathogenesis of transmissible spongiform encephalopathies, a novel point of view as to the induction of the diseases can be proposed. it is hypothesized that neurodegenerative diseases, such as scrapie in sheep and goats and bovine spongiform encephalopathy in cattle (bse), originate from the consumption of glycated proteins contained in their feed. these components are obtained during a high-temperature glycation process.200212027519
[still a small problem with the mad cow disease? creutzfeldt-jakob disease and other prion diseases: current status].this review is based on recent published research on the bse/cjd/vcjd problem mainly from uk, germany and france. the situation in sweden seems to be fortunate for several reasons. the use of meat and bonemeal as animal fodder was forbidden in this country 13 years ago. sweden has not had any sheep with scrapie for many years. no animals with bse have so far been found in our country. the incidence of sporadic cjd in this country followed retrospectively from 1985 to 1996 and prospectively from ...200111213704
phenotype of disease-associated prp accumulation in the brain of bovine spongiform encephalopathy experimentally infected view of the established link between bovine spongiform encephalopathy (bse) and variant creutzfeldt-jakob disease and of the susceptibility of sheep to experimental bse, the detection of potential cases of naturally occurring bse in sheep has become of great importance. in this study, the immunohistochemical (ihc) phenotype of disease-associated prion protein (prp(d)) accumulation has been determined in the brain of 64 sheep, of various breeds and prp genotypes, that had developed neurologica ...200515722546
comparative molecular analysis of the abnormal prion protein in field scrapie cases and experimental bovine spongiform encephalopathy in sheep by use of western blotting and immunohistochemical methods.since the appearance of bovine spongiform encephalopathy (bse) in cattle and its linkage with the human variant of creutzfeldt-jakob disease, the possible spread of this agent to sheep flocks has been of concern as a potential new source of contamination. molecular analysis of the protease cleavage of the abnormal prion protein (prp), by western blotting (prp(res)) or by immunohistochemical methods (prp(d)), has shown some potential to distinguish bse and scrapie in sheep. using a newly develope ...200415016886
[comments on present-day spread and epidemiology of bse and prion diseases].prion diseases of animals and man are neurological diseases with amyloidal deposition of the respective proteins. as to prion disease, the cellular prion protein is in its abnormal isoform(s) an essential component of prion protein aggregates found in affected tissue. in contrast to all neurodegenerative diseases like morbus alzheimer or huntington's disease, prion diseases are transmissible. therefore, prion diseases were designated transmissible spongiform encephalopathies (tse). the diseases ...200414770333
[scrapie in sheep and transmissible encephalopathy of the mink].scrapie in sheep and goat is the prototype of the group of the transmissible spongiform encephalopathies which affect man and some animal species, notably other ruminants with bovine spongiform encephalopathy (bse) and chronic wasting disease of wild ruminants. transmissible mink encephalopathy (tme) is a rare disease of ranch-raised mink caused by exposure to a contaminated food ingredient in the ration scrapie, unrecognised bse-like disease...). there is clinical and pathological similarities ...19957777384
[present-day knowledge of bse and creutzfeldt-jakob disease]. 200312649789
evaluation of rapid tests for the diagnosis of transmissible spongiform encephalopathies in sheep and accordance with eu regulation 999/2001, rapid tests already adopted for bovine spongiform encephalopathy (bse; prionics check western, platelia-bse and enfer tse) are to be applied in all european countries to a sub-population of over 18-month-old slaughtered or dead sheep and goats to improve scrapie surveillance and to determine the possible presence of bse in sheep; however, the three tests have thus far been evaluated only for bse and no official data are available about their performance ...200415067554
alpha-hemoglobin stabilizing protein is not a suitable marker for a screening test for variant creutzfeldt-jakob disease.a test is needed to identify blood donors who are in the preclinical phase of variant creutzfeldt-jakob disease (cjd). alpha-hemoglobin stabilizing protein (ahsp; syn. eraf, edrf) transcript levels are reduced in the blood of mice incubating transmissible spongiform encephalopathy.200818503615
from nannyism to public disclosure: the bse inquiry report. 200111332300
transmission barriers for bovine, ovine, and human prions in transgenic mice.transgenic (tg) mice expressing full-length bovine prion protein (boprp) serially propagate bovine spongiform encephalopathy (bse) prions without posing a transmission barrier. these mice also posed no transmission barrier for suffolk sheep scrapie prions, suggesting that cattle may be highly susceptible to some sheep scrapie strains. tg(boprp) mice were also found to be susceptible to prions from humans with variant creutzfeldt-jakob disease (cjd); on second passage in tg(boprp) mice, the incub ...200515827140
frequency of brain tissue embolism associated with captive bolt gun stunning of accordance with controls instituted to protect the consumer from meat potentially infected with bovine spongiform encephalopathy (bse), brain tissue emboli caused by the use of captive bolt gun (cbg) stunning have been identified as a potential public health risk that requires further investigation. as the natural occurrence of bse in sheep remains uncertain we have investigated the frequency of brain tissue embolism associated with stunning by two types of cbg that are in commercial use in t ...200415992291
theoretical models of sheep bse reveal possibilities. 200211805805
[spongiform encephalopathies with special reference to bovine spongiform encephalopathy].in switzerland bovine spongiform encephalopathy (bse) was detected for the first time in november 1990. it is a transmissible disease of the central nervous system similar to creutzfeldt-jakob disease (cjd), gerstmann-sträussler-scheinker syndrome (gss) and kuru in man, and, in animals, scrapie in sheep and goats, chronic wasting disease (cwd) in captive mule deer and elk of north america and transmissible mink encephalopathy (tme) of farm reared mink. the infectious agent of the spongiform ence ...19921615298
the bse-susceptible proportion of uk sheep. 200212418532
protease-resistant prion protein in brain and lymphoid organs of sheep within a naturally scrapie-infected flock.the hallmark of transmissible spongiform encephalopathies (tse), such as scrapie in sheep, is the accumulation in tissues of an insoluble and protease resistant form (prpres) of the cellular prion protein. in this study, we evaluated whether the diversity in both the clinical pattern and the prp genotypes of scrapied sheep from the same flock was connected with different levels and/or glycoform patterns of the prpres in the brain and lymphoid organs of the animals. whereas the prpres levels in s ...200010839972
the potential for transmissible spongiform encephalopathies in non-ruminant livestock and fish.pigs and poultry in the united kingdom have undeniably been exposed to the bovine spongiform encephalopathy (bse) agent. they consumed the same ruminant protein that gave rise to the bse epidemic in cattle, but there has been no evidence of an epidemic in these species. experimental investigations have shown pigs to be susceptible to infection by multiple parenteral challenge, but resistant to oral exposure with bse-infected cattle brain. current but incomplete evidence suggests that they are al ...200312793786
detection of metazoan species as a public health issue: simple methods for the validation of food safety and quality.species identification represents a critical issue in food chain safety and quality control. several procedures are available to detect animal proteins in cattle feed or to trace transgenic foods. the most effective approach is based on the use of dna as a marker. amplification of dna provides rapid, sensitive and specific protocols. several target genes can be used, but new insights come from the mitochondrial genome, which is naturally amplified in each cell and shows a remarkable resistance t ...200516216782
bovine spongiform encephalopathy: a scrapie-like disease of british cattle.scrapie is a cns degenerative infection of sheep and goats, which is invariably fatal after incubation periods of several months to years. related disorders are found naturally in man and other species. there is a impairment of protein catabolism in scrapie and related diseases which leads to the accumulation of sparingly-soluble protein deposits in brain. these protein aggregates may share with the amyloid of alzheimer's disease (ad) some common stage in the biochemical pathways of their format ...19892574875
gene expression alterations in brains of mice infected with three strains of scrapie.transmissible spongiform encephalopathies (tses) or prion diseases are fatal neurodegenerative disorders which occur in humans and various animal species. examples include creutzfeldt-jakob disease (cjd) in humans, bovine spongiform encephalopathy (bse) in cattle, chronic wasting disease (cwd) in deer and elk, and scrapie in sheep, and experimental mice. to gain insights into tse pathogenesis, we made and used cdna microarrays to identify disease-associated alterations in gene expression. brain ...200616700923
monitoring for bovine spongiform encephalopathy in sheep in great britain, 1998-2004.bovine spongiform encephalopathy (bse) may have been transmitted to british sheep via contaminated feed in the 1980s. strain-typing techniques based on immunohistochemical (ihc) detection of abnormal protein (prp(d)) and the molecular analysis of proteinase-resistant protein (prp(res)) by western blotting (wb) can discriminate between natural or experimental scrapie and experimental bse in sheep. between 1 january 1998 and 31 october 2001, 1247 sheep, clinically suspected of scrapie, were found ...200616760414
searching for bse in sheep: interpreting the results so far. 200312650473
identification of a proteinase k resistant protein for use as an internal positive control marker in prp western blotting.the routine use of an internal positive control (ipc) marker could prove useful in the diagnosis of transmissible spongiform encephalopathy (tse) diseases, particularly in surveillance programmes where large numbers of negative results are reported. detection of an endogenous ipc protein in a negative sample adds confidence to the correct sample processing throughout the analytical procedure and could avoid the reporting of false negative diagnoses. proteinase k (pk) resistance is one of the key ...200717336356
atypical scrapie in a swiss goat and implications for transmissible spongiform encephalopathy surveillance.different types of transmissible spongiform encephalopathies (tses) affect sheep and goats. in addition to the classical form of scrapie, both species are susceptible to experimental infections with the bovine spongiform encephalopathy (bse) agent, and in recent years atypical scrapie cases have been reported in sheep from different european countries. atypical scrapie in sheep is characterized by distinct histopathologic lesions and molecular characteristics of the abnormal scrapie prion protei ...200717459826
detection of central nervous system tissues in meat products: validation and standardization of a real-time pcr-based detection system.several phenotypic as well as genotypic methods have been published describing the detection of central nervous system (cns) tissues that are part of the bovine spongiform encephalopathy (bse) risk material in food products. however, none of these methods is able to differentiate between cns tissue of the banned ruminant species and tissues of other animal species. a quantitative and species-specific real-time rt-pcr method has been developed that enables the reliable identification of cns tissu ...200717507185
tse pathogenesis in cattle and sheep.many studies have been undertaken in rodents to study the pathogenesis of transmissible spongiform encephalopathies (tse). only a few studies have focused on the pathogenesis of bovine spongiform encephalopathy (bse) and scrapie in their natural hosts. in this review, we summarize the most recent insights into the pathogenesis of bse and scrapie starting from the initial uptake of tse agents and crossing of the gut epithelium. following replication in the gut-associated lymphoid tissues (galt), ...200818258167
control of scrapie in the uk sheep population.scrapie is a fatal transmissible spongiform encephalopathy (tse) of sheep, endemic in the uk for centuries. interest in the disease has been heightened over the last decade by the possibility of the related bse being transmissible to and between sheep and a range of control interventions has been proposed and implemented. in this paper, we examined the effect of these policies and their components on observed case rate, susceptible allele frequency and r0 within the framework of a large simulati ...200918687157
differences in proteinase k resistance and neuronal deposition of abnormal prion proteins characterize bovine spongiform encephalopathy (bse) and scrapie strains.prion diseases are associated with the accumulation of an abnormal isoform of host-encoded prion protein (prp(sc)). a number of prion strains can be distinguished by "glycotyping" analysis of the respective deposited prp(sc) compound. in this study, the long-term proteinase k resistance, the molecular mass, and the localization of prp(sc) deposits derived from conventional and transgenic mice inoculated with 11 different bse and scrapie strains or isolates were examined. differences were found i ...199910415165
functional relevance of dna polymorphisms within the promoter region of the prion protein gene and their association to bse infection.transmissible spongiform encephalopathies (tses) are a group of neurodegenerative diseases that can occur spontaneously or can be caused by infection or mutations within the prion protein gene prnp. nonsynonymous dna polymorphisms within the prnp gene have been shown to influence susceptibility/resistance to infection in sheep and humans. analysis of dna polymorphisms within the core promoter region of the prnp gene in four major german bovine breeds resulted in the identification of both snps a ...200717255470
[srm in bse infected animals and food safety]. 200516440797
comparison of strategies for substantiating freedom from scrapie in a sheep flock.the public health threat represented by a potential circulation of bovine spongiform encephalopathy agent in sheep population has led european animal health authorities to launch large screening and genetic selection programmes. if demonstrated, such a circulation would have dramatic economic consequences for sheep breeding sector. in this context, it is important to evaluate the feasibility of qualification procedures that would allow sheep breeders demonstrating their flock is free from scrapi ...200919405956
ovine infection with the agents of scrapie (ch1641 isolate) and bovine spongiform encephalopathy: immunochemical similarities can be resolved by immunohistochemistry.immunochemical ("rapid") tests, which recognize a partly protease-resistant conformer of the prion protein (prp(res)) are now widely used in europe for the diagnosis of transmissible spongiform encephalopathies (tses). some of these tests can be used to distinguish natural scrapie from experimental bovine spongiform encephalopathy (bse) in sheep, on the basis of migration pattern differences of prp(res) in western immunoblots. however, prp(res) from sheep inoculated with ch1641 scrapie gives an ...200616324707
bse inoculation to prion diseases-resistant sheep reveals tricky silent carriers.the possible transmission of bovine spongiform encephalopathy (bse) agent to sheep contributed to select genetically sheep considered as resistant to prion diseases i.e., with prp arr/arr genotype. here, we report the infection of two prp arr/arr genotype sheep using the cattle bse agent inoculated by peripheral routes. disease-associated prion protein (prp(d)) was detected in the brain for one case (at 2191 days post-infection (dpi)) and only in the nervous enteric system for the other one (at ...200617049491
comparison of brain prpd distribution in ovine bse and scrapie.scrapie and bovine spongiform encephalopathy (bse) are both prion diseases affecting ruminants, and these diseases do not share the same public health concerns. surveillance of the bse agent in small ruminants has been a great challenge, and the recent identification of diverse prion diseases in ruminants has led to the development of new methods for strain typing. in our study, using immunohistochemistry (ihc), we assessed the distribution of prp(d) in the brains of 2 experimentally bse-infecte ...201121245284
brief review on the epidemiology of transmissible spongiform encephalopathies (tse).transmissible spongiform encephalopathies (tse) form a group of human and animal diseases that share common features such as (a) distinct pathological lesions in the central nervous system, (b) transmissibility at least in experimental settings, and (c) a long incubation period. considerable differences exist in the host range of individual tses, their routes of transmission, and factors influencing the host susceptibility (such as genotype). the objective of this review was to briefly describe ...200717126962
effect of prp genotype and route of inoculation on the ability of discriminatory western blot to distinguish scrapie from sheep bovine spongiform encephalopathy.procedures for discriminating scrapie from bovine spongiform encephalopathy (bse) in sheep are relevant to ascertain whether bse has entered the sheep population. this study was aimed at investigating whether the suitability of an official eu discriminative method is affected by the sheep prp genotype and route of infection.201121994325
prion protein and the transmissible spongiform encephalopathies.transmissible spongiform encephalopathies (tses) are fatal neurodegenerative diseases that occur in a wide variety of mammals. in humans, tse diseases include kuru, sporadic and iatrogenic creutzfeldt-jakob disease (cjd), gerstmann-sträussler-scheinker syndrome (gss), and fatal familial insomnia (ffi). so far, tse diseases occur only rarely in humans; however, scrapie is a widespread problem in sheep, and the recent epidemic of bovine spongiform encephalopathy (bse or mad cow disease) has seriou ...199717708907
protective effect of the t112 prp variant in sheep challenged with bovine spongiform encephalopathy.sheep with an arq/arq prnp genotype at codon positions 136/154/171 are highly susceptible to experimental infection with bovine spongiform encephalopathy (bse). however, a number of sheep challenged orally or intracerebrally with bse were clinically asymptomatic and found to survive or were diagnosed as bse-negative when culled. sequencing of the full prnp gene open reading frame of bse-susceptible and -resistant sheep indicated that, in the majority of suffolk sheep, resistance was associated w ...200919587133
evaluation of the possible transmission of bse and scrapie to gilthead sea bream (sparus aurata).in transmissible spongiform encephalopathies (tses), a group of fatal neurodegenerative disorders affecting many species, the key event in disease pathogenesis is the accumulation of an abnormal conformational isoform (prp(sc)) of the host-encoded cellular prion protein (prp(c)). while the precise mechanism of the prp(c) to prp(sc) conversion is not understood, it is clear that host prp(c) expression is a prerequisite for effective infectious prion propagation. although there have been many stud ...200919636413
breeding programmes for tse resistance in british sheep. i. assessing the impact on prion protein (prp) genotype frequencies.from april 2005, member states of the european union were required to implement a compulsory breeding programme for resistance to transmissible spongiform encephalopathies (tses) in sheep as part of measures to eradicate tses from national flocks. in this paper, we assessed the impact of four different breeding strategies on prion protein (prp) genotype frequencies using a mathematical model which describes in detail gene flow in the british sheep flock. these strategies ranged from the minimum ...200616169614
detection of bovine spongiform encephalopathy-related prion protein gene promoter polymorphisms in local turkish cattle.polymorphisms in open reading frames of the prion protein gene (prnp) have been shown to be associated with prion disease susceptibility in humans, sheep, and mice. studies in recent years have demonstrated a similar effect of prnp promoter and intron-1 polymorphisms on bovine spongiform encephalopathy (bse) susceptibility in cattle. in this study, the deletion/insertion (indel) polymorphisms of the bovine prnp gene within the promoter sequence (23 bp) and intron 1 (12 bp) were analyzed in local ...200818800245
natural transmission of bse between sheep within an experimental flock. 200516100373
digestion and transportation of bovine spongiform encephalopathy-derived prion protein in the sheep intestine.bovine spongiform encephalopathy (bse) is acquired orally and the mechanisms involved in the absorption and transportation of infectivity across the gut wall are therefore critical. isolated gut loops were created in lambs, massaged to remove intestinal contents (flushed) or left non-flushed, inoculated with cattle bse homogenate and excised at different time-points. gut loops were examined by immunohistochemistry (ihc) for disease-associated prion protein (prp(d)), and the contents were analyse ...201020826616
prp(d) accumulation in organs of arq/arq sheep experimentally infected with bse by peripheral study the pathogenesis of bovine spongiform encephalopathy infection in small ruminants, two lacaune sheep with the aa136rr154qq171 and one with the aa136rr154rr171 genotype for the prion protein, were inoculated with a brain homogenate from a french cattle bse case by peripheral routes. sheep with the arq/arq genotype are considered as susceptible to prion diseases contrary to those with the arr/arr genotype. the accumulation of disease-associated prion protein (prp(d)) was analysed by bioch ...200616770445
immunohistochemical characterisation of classical scrapie neuropathology in sheep.neuroinflammation elicited by prp(res) (resistant prion protein [prp]) deposits in the central nervous system (cns) has been shown to involve cellular and oxidative stress responses in bovine spongiform encephalopathy (bse) as well as in several murine models of transmissible spongiform encephalopathy (tse). additionally, deregulation of water homeostasis has been suggested to be a further component of the spongiform changes observed in tses. the aim of the present study was to characterize the ...200919515381
molecular discrimination of sheep bovine spongiform encephalopathy from scrapie.sheep ch1641-like transmissible spongiform encephalopathy isolates have shown molecular similarities to bovine spongiform encephalopathy (bse) isolates. we report that the prion protein prpsc from sheep bse is extremely resistant to denaturation. this feature, combined with the n-terminal prpsc cleavage, allowed differentiation of classical scrapie, including ch1641-like, from natural goat bse and experimental sheep bse.201121470463
rapid typing of transmissible spongiform encephalopathy strains with differential elisa.the bovine spongiform encephalopathy (bse) agent has been transmitted to humans, leading to variant creutzfeldt-jakob disease. sheep and goats can be experimentally infected by bse and have been potentially exposed to natural bse; however, whether bse can be transmitted to small ruminants is not known. based on the particular biochemical properties of the abnormal prion protein (prpsc) associated with bse, and particularly the increased degradation induced by proteinase k in the n terminal part ...200818394279
BSE: where are we now? 201121965237
atypical/nor98 scrapie infectivity in sheep peripheral tissues.atypical/nor98 scrapie was first identified in 1998 in norway. it is now considered as a worldwide disease of small ruminants and currently represents a significant part of the detected transmissible spongiform encephalopathies (tse) cases in europe. atypical/nor98 scrapie cases were reported in arr/arr sheep, which are highly resistant to bse and other small ruminants tse agents. the biology and pathogenesis of the atypical/nor98 scrapie agent in its natural host is still poorly understood. how ...201121347349
prpsc spreading patterns in the brain of sheep linked to different prion types.abstract: scrapie in sheep and goats has been known for more than 250 years and belongs nowadays to the so-called prion diseases that also include e.g. bovine spongiform encephalopathy in cattle (bse) and creutzfeldt-jakob disease in humans. according to the prion hypothesis, the pathological isoform (prpsc) of the cellular prion protein (prpc) comprises the essential, if not exclusive, component of the transmissible agent. currently, two types of scrapie disease are known - classical and atypic ...201121324114
oral transmission of bse to vrq/vrq sheep in an experimental flock. 200818223273
heart rate variability analysis in sheep affected by transmissible spongiform encephalopathies.abstract:201122168827
isolation from cattle of a prion strain distinct from that causing bovine spongiform date, bovine spongiform encephalopathy (bse) and its human counterpart, variant creutzfeldt-jakob disease, have been associated with a single prion strain. this strain is characterised by a unique and remarkably stable biochemical profile of abnormal protease-resistant prion protein (prp(res)) isolated from brains of affected animals or humans. however, alternate prp(res) signatures in cattle have recently been discovered through large-scale screening. to test whether these also represent sep ...200617054396
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