Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
|---|
| surveillance for scrapie. | 2000 | 10888003 | |
| molecular analysis of irish sheep scrapie cases. | 2000 | 10900052 | |
| prevalence of vacuolar lesions consistent with scrapie in the brains of healthy cull sheep of the shetland islands. | to determine the levels of background scrapie-like pathology in the brains of clinically normal adult sheep, the brains of 1106 sheep from 28 known scrapie-infected flocks and nine apparently uninfected flocks were examined during 1998 and 1999. one per cent of the brains had vacuolar pathology and disease-specific accumulations of prion protein consistent with a diagnosis of scrapie. all the positive animals had at least one allele of the prion protein gene encoding valine at codon 136, and ori ... | 2000 | 11079439 |
| 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 ... | 2000 | 11087170 |
| suitability of protuberances on the third eyelids of sheep as a biopsy site for lymphoid follicles. | 2000 | 11128078 | |
| 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 ... | 2000 | 11214922 |
| 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 ... | 2000 | 11214925 |
| molecular analysis of ovine prion protein identifies similarities between bse and an experimental isolate of natural scrapie, ch1641. | new 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 ... | 1999 | 9934675 |
| 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 ... | 1999 | 10073715 |
| scrapie-associated prion protein in the gastrointestinal tract of sheep with natural scrapie. | the scrapie-associated prion protein (prpsc), which is closely associated with scrapie infectivity, accumulates in the brain and lymphoid tissues of sheep with natural scrapie. the most probable portal of entry of the scrapie agent in sheep is the alimentary tract; little attention, however, has been paid to the gastro-intestinal tract in scrapie research. in this study, we examined the presence and distribution of prpsc within the gastro-intestinal tract of sheep with natural scrapie and scrapi ... | 1999 | 10373293 |
| 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. | 1999 | 10386559 |
| 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 ... | 1999 | 10415165 |
| 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 ... | 1999 | 10569779 |
| exacerbated spongiform lesions in the cerebral cortex in japanese sheep, in an outbreak of scrapie during 1984-1987. | the present study dealt with the pathology of natural scrapie in japanese suffolk sheep in a certain selected area. vacuolations in the cytoplasm of neurons were conspicuous. they were particularly evident in many areas of the medulla and pons, extending into and through pedunculus cerebri and thalamus to the septal area and olfactory tubercle. proliferation of astrocytes was also easily observed with glial fibrillary acidic protein staining. neural vacuolations in the cerebral cortex were obser ... | 1999 | 10738362 |
| astrocytosis and proliferating cell nuclear antigen expression in brains of scrapie-infected hamsters. | scrapie is a neurodegenerative disease in sheep and goats. neuropathological examination shows astrocytosis. one issue is whether the astrocytosis seen in scrapie is a function of an increase in reactivity of individual cells, or whether there is actual replication of astrocytes. we used double-label immunohistochemistry for proliferating cell nuclear antigen (pcna) and for glial fibrillary acidic protein (gfap) to determine the mitotic state of cells and to confirm their identity as astrocytes. ... | 1998 | 10344795 |
| an immunological approach to prion diseases. | ovine scrapie and bovine spongiform encephalopathy are genetic diseases, presenting probably autoimmunity transmissible by the oral route. the absence of immune response in prion diseases indicates a tolerant state for prp(c) and prp(sc). the tolerant state against these diseases should be overcome before immunizing animals. we suggest that an early diagnosis may be possible using polyclonal and monoclonal antibodies specific for either ovine or bovine prp(sc). such reagents could be obtained by ... | 1998 | 9488187 |
| comparison of scrapie-associated fibril detection and western immunoblotting for the diagnosis of natural ovine scrapie. | detergent- and proteinase k-treated extracts of grey matter were prepared from four regions of the brains of 106 sheep with scrapie, diagnosed clinically and by the demonstration of spongiform encephalopathy. the extracts were examined by electron microscopy for the presence of scrapie-associated fibrils and by western immunoblotting for the disease-specific abnormal prion protein (prpsc). as a diagnostic method, western immunoblotting proved to be more sensitive than electron microscopy, the de ... | 1998 | 9500237 |
| melatonin and prolactin secretion profile in naturally occurring scrapie in ewe. | the 24 hr pattern of melatonin secretion was determined in scrapie-affected ewes during the clinical course of the disease. the melatonin response to a night interruption by a 1 hr period of illumination was also measured. fourteen ewes (seven control and seven scrapie-affected ewes) were subjected to artificial short days (9l:15d). four 24 hr blood sampling sessions separated by about 10 days were performed. ewes were sacrificed when clinical signs had progressed to irreversible recumbency and ... | 1998 | 9510437 |
| 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 ... | 1998 | 9568991 |
| an antibody raised against a conserved sequence of the prion protein recognizes pathological isoforms in human and animal prion diseases, including creutzfeldt-jakob disease and bovine spongiform encephalopathy. | antibodies to the prion protein (prp) have been critical to the neuropathological and biochemical characterization of prp-related degenerative diseases in humans and animals. although prp is highly conserved evolutionarily, there is some sequence divergence among species; as a consequence, anti-prp antibodies have a wide spectrum of reactivity (from strong immunopositivity to lack of reactivity) when challenged with prp from diverse species. we have produced an antibody (anti-prp95-108) raised a ... | 1998 | 9626045 |
| scrapie. | scrapie and other transmissible spongiform encephalopathies (tses) are characterized by similar pathology, biochemistry and genetics. the prp protein and its conversion to the disease-related isoform, prpsc, are crucial for the development of all tses. although scrapie is more often studied in laboratory rodents, it is not a natural disease of these animals, and much can be learned from the normal hosts, sheep. disease incidence is linked to polymorphisms and mutations of the prp gene. the compl ... | 1998 | 9718582 |
| urodynamic parameters in scrapie-affected ewes and their modifications in the course of the disease. | the aim of this study was to determine the urological abnormalities linked to spontaneous spongiform encephalopathy and their occurrence in the course of the disease. the animals used in this were 11 healthy and 20 scrapie-affected ewes. the scrapie-affected ewes were studied at a rate of once a month (1 to 5 measures; mean, 2.55) until they died. urodynamic explorations were performed. the bladder activity was explored using cystometry. the urethral activity was measured during cystometry and d ... | 1998 | 9776019 |
| complete genomic sequence and analysis of the prion protein gene region from three mammalian species. | the prion protein (prp), first identified in scrapie-infected rodents, is encoded by a single exon of a single-copy chromosomal gene. in addition to the protein-coding exon, prp genes in mammals contain one or two 5'-noncoding exons. to learn more about the genomic organization of regions surrounding the prp exons, we sequenced 10(5) bp of dna from clones containing human, sheep, and mouse prp genes isolated in cosmids or lambda phage. our findings are as follows: (1) although the human prp tran ... | 1998 | 9799790 |
| a mathematical model of the dynamics of scrapie in a sheep flock. | a mathematical model is developed for the dynamics of an outbreak of scrapie in a single sheep flock with the aim of assisting the interpretation of field data. the model incorporates age structure of the sheep population, both horizontal and vertical transmission, genetic predisposition to infection, variable initial load of the infectious agent, and increasing infection load during an incubation period of the same order as sheep life expectancy. this leads to system of partial differential equ ... | 1998 | 9825634 |
| bovine spongiform encephalopathy: current status and possible impacts. | bovine spongiform encephalopathy is an apparently new disease; first recognized in 1985, its pathological distinction was first reported in 1986. bovine spongiform encephalopathy is a member of a group of transmissible encephalopathies that includes scrapie in sheep and creutzfeldt-jakob disease in humans. early indications of its epidemiology suggested that the disease was transmitted via cattle feed containing meat and bone meals from previously infected animals. the tissues most likely to con ... | 1998 | 9839244 |
| the shortest known prion protein gene allele occurs in goats, has only three octapeptide repeats and is non-pathogenic. | the prion protein (prp) gene modulates the incidence and incubation periods of transmissible spongiform encephalopathies of sheep, goats, mice and man. here, a new caprine prp allele encoding the shortest naturally occurring prp protein so far described is reported. this variant contains only three instead of the usual five copies of a short peptide repeat [pro-gln/his-gly-gly-gly-(gly)-trpgly-gln] characteristic of prp, with an additional trp to gly substitution in codon 102. fifteen out of 111 ... | 1998 | 9880037 |
| 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 ... | 1997 | 9581370 |
| [molecular pathogenesis of spongiform encephalopathy]. | 1997 | 9489393 | |
| biochemical typing of scrapie strains. | 1997 | 9121579 | |
| prp genotypes and experimental scrapie in orally inoculated suffolk sheep in the united states. | one-hundred and three unites states suffolk sheep were inoculated orally with a scrapie agent preparation and monitored for clinical disease and histopathological lesions characteristic of scrapie. a retrospective study of the polymorphisms at codon 171 of the prion protein (prp) gene was performed on these sheep. all 63 sheep that developed scrapie during the observation period were homozygous for the glutamine 171 (171-qq) prp allele. twelve 171-qq sheep failed to develop disease. all 5 sheep ... | 1997 | 9129673 |
| [prion disease in animals and experimental prion disease]. | 1997 | 9282362 | |
| syrian hamster prion protein (prp(c)) is expressed in photoreceptor cells of the adult retina. | prp(c), the cellular isoform of the prion protein (prp) serves as a precursor to abnormal prp isoforms which accumulate in diseases such as scrapie in sheep, and creutzfeldt-jakob disease in humans. since prions can replicate in photoreceptors we surmised that prp(c) must be expressed in these cells. accordingly, monoclonal antisera directed against two epitopes of hamster prp(c) produced retinal immunostaining in hamsters, and in mice bearing a hamster prp transgene. immunostaining was most pro ... | 1997 | 9347934 |
| 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 ... | 1997 | 17708907 |
| [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 ... | 1996 | 9128415 |
| creutzfeldt-jakob disease and bovine spongiform encephalopathy. aetiology of scrapie in certain circumstances is not evidence against another aetiology in different circumstances. | 1996 | 8563543 | |
| [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 ... | 1996 | 8658476 |
| 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 ... | 1996 | 8758005 |
| 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 ... | 1996 | 8760446 |
| observations on the transmission of scrapie in experiments using embryo transfer. | this investigation studied the maternal transmission of scrapie in sheep by using embryo transfer to examine the viability of highly susceptible offspring derived from scrapie-affected and uninfected donors. the study also examined the effect of washing the embryos. scrapie occurred in both washed and unwashed embryo-derived sip sasa progeny from both groups of donor ewes. as a result, the earlier observation that scrapie might pass via the unwashed embryo to develop as disease in adult sheep ha ... | 1996 | 8795182 |
| spongiform encephalopathies: still many unanswered questions. | 1996 | 8795492 | |
| endosome-lysosomes, ubiquitin and neurodegeneration. | before the advent of ubiquitin immunochemistry and immunogold electron microscopy, there was no known intracellular molecular commonality between neurodegenerative diseases. the application of antibodies which primarily detect ubiquitin protein conjugates has shown that all of the human and animal idiopathic and transmissible chronic neurodegenerative diseases, (including alzheimer's disease (ad), lewy body disease (lbd), amyotrophic lateral sclerosis (als), creutzfeldt-jakob disease (cjd) and s ... | 1996 | 8861020 |
| prp genotype contributes to determining survival times of sheep with natural scrapie. | several allelic variants of the sheep prp gene are associated with scrapie susceptibility. however, it is not known whether, and to what extent, the prp genotype contributes to determining survival times of scrapie sheep. we therefore determined the prp genotype and life spans of over 50 flemish and swifter sheep within a single scrapie-affected flock. eighty-three per cent of the scrapie sheep were homozygous for the prp(vq) allele (polymorphic amino acids at codons 136 and 171 are indicated) a ... | 1996 | 8887505 |
| improvement of prpsc-detection in mouse spleen early at the preclinical stage of scrapie with collagenase-completed tissue homogenization and sarkosyl-nacl extraction of prpsc. | scrapie in sheep has recently become again a target of control measures and eradication programs. crucial for the effectiveness of these measures is the detection of infected sheep during the long and potentially hazardous incubation period. however, routine-diagnosis is mostly limited to clinical examinations when disease becomes apparent, and to postmortem investigations. through the detection of the scrapie-specific isoform of the prion protein (prpsc) by western blot in the spleen and lymph ... | 1996 | 8920821 |
| 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 ... | 1996 | 9119148 |
| comparative study of electron microscopical techniques for the detection of scrapie-associated fibrils. | samples of cervical spinal cord and four anatomical regions of the brains of 12 sheep with natural scrapie and six control sheep were examined by electron microscopy, after the tissues had been stored at 4 degrees c and -20 degrees c. the tissues were tested for the presence of scrapie-associated fibrils by a centrifugal extraction technique and by a touch-grid technique. the touch-grid technique was no better than the centrifugal extraction technique for the detection of fibrils. structures whi ... | 1995 | 8588101 |
| identification of five allelic variants of the sheep prp gene and their association with natural scrapie. | scrapie is a fatal neurodegenerative disease of sheep that belongs to the group of prion diseases found in humans and animals. the host encoded prion protein (prp) plays a central role in the disease process. in the prp genes of man, mice and sheep, polymorphisms have been found that are associated with disease susceptibility and pathogenesis. we have used denaturing gradient gel electrophoresis (dgge) to detect polymorphisms in the sheep prp gene. in addition to the already described polymorphi ... | 1995 | 7897344 |
| 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 ... | 1995 | 7595360 |
| a cellular form of prion protein (prpc) exists in many non-neuronal tissues of sheep. | a cellular form of the prion protein (prpc) is thought to be a substrate for an abnormal isoform of th eprion protein (prpsc) in scrapie. prpc is abundant in tissues of the central nervous system, but little is known about the distribution of prpc in non-neuronal tissues of sheep, the natural host of scrapie. this study investigated the tissue distribution of prpc in sheep. although prpc was abundant in neuronal tissues, it was detected in non-neuronal tissues such as spleen, lymph node, lung, h ... | 1995 | 7595362 |
| intracerebral distribution of infectious amyloid protein in spongiform encephalopathy. | we studied the regional distribution of infectious amyloid protein by western immunoblots of brain tissue extracts from 37 patients with different forms of spongiform encephalopathy, i.e., 16 sporadic cases, 18 familial cases with a variety of mutations, and 3 iatrogenic cases. in sporadic and familial creutzfeldt-jakob disease, amyloid protein concentrations were usually highest in the frontotemporal regions of the cerebral cortex, whereas iatrogenic creutzfeldt-jakob disease and gerstmann-strä ... | 1995 | 7654073 |
| [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 ... | 1995 | 7777384 |
| seac reports on transmissible spongiform encephalopathies. | 1995 | 7793019 | |
| endosome-lysosomes and neurodegeneration. | a number of the major human and animal neurodegenerative diseases, such as alzheimer's disease and sheep scrapie, are characterised by deposits of amyloid, arising through incomplete breakdown of membrane proteins. although our knowledge concerning these diseases is increasing, they remain largely untreatable. recently, attention has focussed on the mechanisms of production of different types of amyloid and the likely involvement within cells of acid compartments called endosome-lysosomes. these ... | 1994 | 7858158 |
| prp genotypes and the sip gene in cheviot sheep form the basis for scrapie strain typing in sheep. | 1994 | 8030950 | |
| bse awareness programme in tasmania. | 1994 | 8059517 | |
| detection of apoptosis induced dna cleavage in scrapie-infected sheep brain. | the pathogenesis and molecular basis of nerve cell death which accompanies scrapie infections in sheep are not well understood. degeneration of neurons in culture caused by prion protein fragments has recently been reported to be consistent with mechanisms of cell death by apoptosis or programmed cell death. apoptosis activation during prion-related encephalopathies has not yet been established in vivo. we report here the detection of dna damage consistent with apoptosis in the brain cells of sh ... | 1994 | 8138146 |
| structure and polymorphism of the mouse prion protein gene. | missense mutations in the prion protein (prp) gene, overexpression of the cellular isoform of prp (prpc), and infection with prions containing the scrapie isoform of prp (prpsc) all cause neurodegenerative disease. to understand better the physiology and expression of prpc, we retrieved mouse prp gene (prn-p) yeast artificial chromosome (yac), cosmid, phage, and cdna clones. physical mapping positions prn-p approximately 300 kb from ecotropic virus integration site number 4 (evi-4), compatible w ... | 1994 | 7912827 |
| 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. | 1993 | 8017235 |
| human prion diseases (spongiform encephalopathies). | prion diseases (spongiform encephalopathies) in humans are creutzfeldt-jakob disease (cjd), gerstmann-sträussler-scheinker syndrome (gss), and kuru. clinically, they are characterized by an inexorably progressing neurological illness with dementia and ataxia as the most prominent signs. the classical neuropathological changes are limited to the central nervous system and consist of spongiform degeneration, amyloid plaques, astrocytic gliosis, and nerve cell loss. the human spongiform encephalopa ... | 1993 | 8219808 |
| scrapie control in the united states. | 1993 | 8236771 | |
| bovine spongiform encephalopathy. | 1993 | 8288469 | |
| risk analysis and the importation of animals and animal products. | importation of animals or animal products cannot take place without some element of risk. risk analysis is a blend of art and science and is a tool intended to provide decision-makers with an objective, repeatable and defensible assessment of the risks posed by a particular import proposal. risk analysis comprises risk identification, risk assessment, risk management and risk communication. examples are presented of risk analysis involving anthrax in green hides, slow virus diseases and sheep em ... | 1993 | 8312612 |
| french autochthonous scrapied sheep without the 136val prp polymorphism. | 1993 | 8104061 | |
| 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 ... | 1993 | 8137130 |
| 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 ... | 1993 | 7687651 |
| [prion encephalopathies]. | spongiform encephalopathies, also called prion encephalopathies, are characterized, in human as well as in animals, by (1) their clinical picture which indicates strict localisation in central nervous system, (2) their histological aspect: spongiform degeneration and neuronal loss, and (3) their transmissibility in the same animal species but also from man to animal. the nature of the pathogenic agent is still debated. this agent could be one isoform of the prion protein which, probably because ... | 1992 | 1288542 |
| immunoreactivity to ubiquitin-protein conjugates is present early in the disease process in the brains of scrapie-infected mice. | brains from mice infected with either the 87v or the me7 strains of mouse-passaged sheep scrapie were taken at stages during the disease process and immunostained to show the localization of ubiquitin-protein conjugates. in both models, conjugates were seen as fine, dot-like structures; as coarser, granular lesions within or adjacent to neurones; and in areas surrounding plaques. the dot-like structures were visible at 28 days post-me7 infection and at 55 days in 87v-infected mice. in both model ... | 1992 | 1334140 |
| a specific rflp type associated with the occurrence of sheep scrapie in japan. | we have investigated restriction fragment length polymorphism (rflp) on the prp gene and the frequencies of rflp patterns in 35 healthy suffolk sheep randomly collected. according to the combinations of prp encoding dna fragments generated by restriction enzymes eco ri and hind iii, the rflp patterns were classified into six types and designated as types i to vi. the frequencies of these types were as follows: i, 8.6%; ii, 11.4%; iii, 17.6%; iv, 11.4%; v, 28.6%; and vi, 22.9%. in 10 sheep diagno ... | 1992 | 1360795 |
| hidden amyloidoses. | the pathogenesis as well as the genetic disposition to develop clinical symptoms in transmissible spongiform encephalopathies (e.g. creutzfeldt-jakob disease, scrapie, bovine spongiform encephalopathy) relate these diseases to classical noninfectious amyloidoses (familial amyloidotic polyneuropathy as an example) and to alzheimer's disease. this is not obvious to the nonexpert at first glance. this communication tries to elucidate this association, to reveal which immunochemical techniques have ... | 1992 | 1364008 |
| 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 ... | 1992 | 1364085 |
| molecular cloning of a mink prion protein gene. | transmissible mink encephalopathy (tme) is a rare disease which is presumably transmitted to ranch-raised mink from scrapie-infected sheep offal or bovine spongiform encephalopathy-infected cattle products. although the infectious agent of tme has not been isolated, there is circumstantial evidence that tme is caused by prions. the experimental host range of tme includes sheep, cattle, monkeys and hamsters. however, tme has never been transmitted to mice. since experiments in transgenic animals ... | 1992 | 1383401 |
| analysis of cerebrospinal fluid from field cases of some common ovine neurological diseases. | analysis of cerebrospinal fluid (csf) samples from normal sheep and from cases of some common neurological diseases revealed a significant increase (p less than 0.05) in the group mean csf protein concentration for meningitis, listeriosis and spinal abscess but not for scrapie, spinal injury, ovine pregnancy toxaemia or polioencephalomalacia. the csf white blood cell count (wbc) was significantly increased (p less than 0.05) in the meningitis group and in those cases of listeriosis which failed ... | 1992 | 1551009 |
| purification of non-infectious ganglioside preparations from scrapie-infected brain tissue. | the extraction and purification of gangliosides from brains of animals infected with the scrapie agent was evaluated by scaling-down a large-scale procedure currently used with bovine brains. inactivation experiments employed hamster brains infected with the 263 k strain of scrapie. residual infectivity was determined at different points of the procedure and in the final preparation by an in vivo animal bioassay. the efficacy of single steps, which included chemicals or physical techniques known ... | 1992 | 1571012 |
| scrapie: a clinical assessment. | 1992 | 1604786 | |
| [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 ... | 1992 | 1615298 |
| molecular biology and pathology of scrapie and the prion diseases of humans. | scrapie and bovine spongiform encephalopathy of animals and creutzfeldt-jakob and gerstmann-sträussler-scheinker diseases of humans are transmissible and genetic neurodegenerative diseases caused by prions. infectious prion particles are composed largely, if not entirely, of an abnormal isoform of the prion protein which is encoded by a chromosomal gene. an as yet unidentified post-translational process converts the cellular prion protein into an abnormal isoform. scrapie neuropathology, incubat ... | 1991 | 1669719 |
| 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 ... | 1991 | 1688299 |
| some problems of diagnosis of the spongiform encephalopathies in ruminants. | the difficulties of a positive diagnosis in the spongiform encephalopathies based only on epidemiological and clinical data are briefly reviewed. however, in b.s.e. as in scrapie, the epidemiology and the clinical data may frequently suggest these diseases. the main diseases which must be taken into account in the differential diagnosis of both spongiform encephalopathies are discussed and the criteria of the differential diagnosis are tabulated. | 1991 | 1761111 |
| genetic and environmental factors determining the development of creutzfeldt-jakob disease in libyan jews. | the cluster of creutzfeldt-jakob disease (cjd) among jews of libyan origin is one of the largest in the world. a number of hypotheses have been proposed to account for this cluster, the most prevalent but unsubstantiated hypothesis being that a transmissible agent was ingested in the form of scrapie-infected sheep brains. it has, however, been shown that a modified host protein encoded by the gene specifying the scrapie amyloid precursor is critically involved in the pathogenesis of transmissibl ... | 1991 | 1798423 |
| natural transmission and genetic control of susceptibility of sheep to scrapie. | 1991 | 1810708 | |
| epidemiological and experimental studies on a new incident of transmissible mink encephalopathy. | epidemiological investigation of a new incident of transmissible mink encephalopathy (tme) in stetsonville, wisconsin, u.s.a. in 1985 revealed that the mink rancher had never fed sheep products to his mink but did feed them large amounts of products from fallen or sick dairy cattle. to investigate the possibility that this occurrence of tme may have resulted from exposure to infected cattle, two holstein bull calves were injected intracerebrally with mink brain from the stetsonville ranch. each ... | 1991 | 1826023 |
| diagnosis of scrapie. | 1991 | 1859542 | |
| naturally occurring scrapie-like spongiform encephalopathy in five domestic cats. | naturally occurring transmissible spongiform encephalopathies have been recognised in sheep, man, mink, captive deer and cattle. recently a similar disease was reported in a domestic cat. this paper describes the clinical and pathological findings in five cats with similar signs, including further observations on the original case. all the cats had a progressive, neurological disease involving locomotor disturbances, abnormal behaviour and, in most cases, altered sensory responses. histopatholog ... | 1991 | 1957458 |
| experimental transmission of scrapie to cattle. | 1990 | 1971338 | |
| detection of bovine spongiform encephalopathy in the united kingdom. | 1990 | 1971813 | |
| structure of scrapie-associated protein and its relation to infectivity. | 1990 | 1971816 | |
| [the biology of prions, a response to the enigma of spongiform encephalopathies of sheep and humans]. | prions are small proteinaceous infectious particles without nucleic acids. the prion protein arise from a cellular protein by a post-transduction event and constitute amyloid deposits. prions are the agent of animal and human spongiform encephalopathies which evolve on simultaneous infectious and genetic dependence in the absence of a detectable immune response. | 1990 | 2094563 |
| proceedings of an international roundtable on bovine spongiform encephalopathy. | 1990 | 2189852 | |
| bovine spongiform encephalopathy--a new disease transmissable to humans? | current concerns about the cattle disease bovine spongiform encephalopathy do not appear to take cognisance of the parallel with scrapie, the similar/identical disease of sheep/goats. this has existed for 200 years, and clearly involved a longstanding consumption of meat/offal from affected animals, but apparently without consequential human disease. a summary is given of the characteristics of the human and animal spongiform encephalopathy diseases and their causative agents. the conclusion of ... | 1990 | 2233424 |
| a questionnaire survey of the prevalence of scrapie in sheep in britain. | an anonymous, self-administered questionnaire has been used in two independent surveys to try to determine the prevalence of scrapie in the national sheep flock. the disease was recorded in 35 counties in england and wales. about a third (26.5 and 37.3 percent) of respondents owning 100 or more sheep indicated that they had seen sheep with scrapie in their flocks. the incidences of clinical cases recorded in affected flocks in the two surveys were 0.5 and 1.1 cases/100 ewes/year. at present ther ... | 1990 | 2260251 |
| tainted feed, mad cows. could a british cattle disease infect u.s. herds? | 1990 | 2333492 | |
| the scrapie control program in the united states. | 1990 | 2347767 | |
| the unexpected export? | 1990 | 2348869 | |
| link between scrapie and bse? | 1990 | 2366871 | |
| scrapie prion proteins accumulate in the cytoplasm of persistently infected cultured cells. | the cellular prion protein (prpc) is a sialoglycoprotein anchored to the external surface of cells by a glycosyl phosphatidylinositol moiety. during scrapie, an abnormal prp isoform designated prpsc accumulates, and much evidence argues that it is a major and necessary component of the infectious prion. based on the resistance of native prpsc to proteolysis and to digestion with phosphatidylinositol-specific phospholipase c as well as the enhancement of prpsc immunoreactivity after denaturation, ... | 1990 | 1693623 |
| polyclonal increase in certain igg subclasses in mice persistently infected with the 87v strain of scrapie. | eight different combinations of seven strains of scrapie agent and the three known sinc genotypes of mice were screened for changes in the concentration of igg in serum. a single radial immunodiffusion assay was used to measure igg throughout the incubation period which in different models ranged from an average of 125 days to longer than the maximum observation period of about 600 days. the only major changes occurred with the 87v strain of scrapie injected intracerebrally (i.c.) or intraperito ... | 1989 | 2507597 |
| 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 ... | 1989 | 2574875 |
| classic genetics of scrapie. | many years ago, observations of natural scrapie revealed differences in clinical manifestations and in the areas of the brain that showed the most intense histopathological changes. in experimental work with scrapie in mice two fundamental points were established in early studies: (1) a mouse gene, termed sinc for scrapie incubation, affects the length of the incubation period. (2) in a single strain of mice, incubation periods of different "strains" of scrapie can differ by as much as 3-4 fold, ... | 1989 | 2690115 |
| scrapie and the sheep mhc: claims of linkage refuted. | 1989 | 2731967 | |
| immunostaining of scrapie cerebral amyloid plaques with antisera raised to scrapie-associated fibrils (saf). | brain sections from 16 different mouse scrapie models were immunostained with antisera to scrapie-associated fibrils (saf) from three experimental scrapie sources (hamster 263k, mouse me7 and mouse 22l). these models involved seven strains of scrapie injected intracerebrally or intraperitoneally into a range of inbred mouse strains, producing a wide variety of neuropathological changes. the only brain structures which were positively immunostained were amyloid plaque cores in those models in whi ... | 1988 | 3221978 |
| bovine spongiform encephalopathy: time to take scrapie seriously. | 1988 | 3394240 |