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
[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
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
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
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
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
[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
epidemiological observations on spongiform encephalopathies in captive wild animals in the british isles.since 1986, scrapie-like spongiform encephalopathy has been diagnosed in 19 captive wild animals of eight species at or from eight zoological collections in the british isles. the affected animals have comprised members of the family bovidae: one nyala (tragelaphus angasi), four eland (taurotragus oryx), and six greater kudu (tragelaphus strepsiceros), one gemsbok (oryx gazella), one arabian oryx (oryx leucoryx), and one scimitar-horned oryx (oryx dammah), and members of the family felidae: four ...19947817514
weak evidence for human link to bse infected meat. 19948107788
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
bse--a risk for man through pharmaceutical products? position and politics of the german pharmaceutical industry.since bse is not a zoonosis and the occurrence is with some exceptions extremely low or absent, the risk to man through pharmaceuticals is remote. however, the agent of bse is very resistant and the disease in cattle is always lethal, as are analogous diseases of man. therefore, the german pharmaceutical industry, through a working group, actively contributes to reasonable measurements leading to a further reduction of any theoretical risk. this theoretical risk has to be evaluated by a balanced ...19938270110
[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
[epidemiology of human prion diseases].prions(proteinaceous infectious particles) are responsible to subacute spongiform encephalopathies(sse) in man and animals. recent outbreak of bovine sse(bse), or mad cow disease in uk provoked concerns on its possible human hazards. a statement of the british government in march 1996 upset the world, which was based on 10 cases of "new variant" form of creutzfelds-jakob disease(cjd). prion diseases in animals are often epizootic and may be spread to different species through various routes incl ...19979103905
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
[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
new studies affirm bse-human link. 19979340753
elevation of apolipoprotein e in the csf of cattle affected by bse.the cerebrospinal fluid (csf) of patients suffering from creutzfeldt-jakob disease (cjd) display two unique polypeptide chains by two-dimensional polyacrylamide gel electrophoresis (2-d page). in the absence of a well-defined ante-mortem diagnostic test for bovine spongiform encephalopathy (bse), spinal fluid samples of eight normal cows and eight cows known to carry bse by post-mortem histological analysis were investigated to verify if equivalent polypeptides were present. proteins with simila ...19979369204
emerging emerging virus is a term applied to a newly discovered virus, one that is increasing in incidence or with the potential to increase in incidence. many viruses fit into this definition. hiv is the clearest example of a previously unknown virus that has now produced one of the largest pandemics in history. recent advances have occurred in the identification and understanding of new hantaviruses in the americas, causing an acute respiratory disease. the possible causal role of human herpesvirus ...19989529635
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
new variant creutzfeldt-jakob variant creutzfeldt-jakob disease is a novel human prion disorder with characteristic clinical and neuropathological features, which results from exposure to the bovine spongiform encephalopathy agent. the probably lengthy incubation period makes it difficult to predict future new variant creutzfeldt-jakob disease case numbers; further studies are required to clarify risk factors and the potential for human spread.19989642546
[transmissible spongiform encephalopathy].transmissible spongiform encephalopaties (tse) are a group of rare fatal diseases of humans and animals. prions, small infectious proteinaceous particles, are their supposed cause. prusiner's theory (nobel price 1997) proves that pathogenetically active prions are conformated physiological prions but problems of pathogenesis of tse are still open. most important representative of human tse is creutzfeldt-jakob's disease (cjd), that of animal tes is bovine spongiform encephalopathy (bse). it seem ...19989650345
an overview of the bse epidemic in the uk.the bse epidemic in the uk is declining rapidly in response to control measures and is en route for eradication by the year 2001. bse infectivity is restricted in clinically affected natural cases of bse to central nervous tissues. bse agent has been isolated from the intestine of experimentally orally-infected cattle from six to 18 months post-challenge. a small maternal risk factor for bse has been identified but this will not stop the eradication of bse. to protect the integrity of biological ...19989737379
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
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
[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
[psychiatric manifestations of a new variant of creutzfeldt-jakob disease. apropos of a case].the new variant of creutzfeldt-jakob disease (nvcjd) was first described in the uk in 1996 (16). the nvcjd differs from sporadic, genetic and iatrogenic cjd. creutzfeldt-jakob disease is closely associated with an abnormal isoform prpsc of a cell-surface glycoprotein, prion protein (14). molecular analysis suggests that nvcjd is caused by the same prion strain as bovine spongiform encephalopathy (bse) (4, 10). to the end of september 2000, there have been 82 cases of nvcjd in the uk. we report t ...200111407273
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
[prions, epidemic of creutzfeldt-jakob variant disease and global emergency].we present here the current understanding of "prion" theory and global risk for epidemics of variant creutzfeldt-jakob disease (vcjd). prion is the infectious agent of all transmissible spongiform encephalopaties (tses). it is regarded as an aggregate of a pathological conformer (prpsc) of a normal cellular glycoprotein (prpc) encoded by a gene, in humans on chromosome 20. the differences between prpsc and prpc are largely if not exclusively conformational; prpc is mostly alpha-helical while prp ...200111873615
brain in human nutrition and variant creutzfeldt-jakob disease risk (vcjd): detection of brain in retail liver sausages using cholesterol and neuron specific enolase (nse) as information is available about the consumption of brain via meat products. with respect to the new variant of creutzfeldt-jakob disease (vcjd) and the presumed food-borne transmission of bovine spongiform encephalopathy (bse) to humans, a preliminary survey for brain and/or spinal cord (tissues of the central nervous system, cns) was conducted. we applied a previously developed integrated procedure using cholesterol and neuron specific enolase (nse) as markers. quantification of cholesterol h ...200111520429
correlative light and backscattered electron microscopy of bone--part ii: automated image analysis.detailed studies of biological phenomena often involve multiple microscopy and imaging modes and media. for bone biology, various forms of light and electron microscopy are used to study the microscopic structure of bone. integrating information from the different sources is necessary to understand how different aspects of the bone structure interact. to accomplish this, methods were developed to prepare and image thin sections for correlative light microscopy (lm) and backscattered electron ima ...200011145258
plus ça change ... from rinderpest to bovine spongiform encephalopathy.cattle plague (rinderpest) caused serious loss of cattle in europe up to the beginning of the 20th century. effective control measures were developed in the 18th century by lancisi in italy and vicq d'azyr in france long before the viral nature of the disease was understood. similar measures are used to control bse, which unlike rinderpest, also infects man. much can be learned from earlier work on such problems as failure to notify outbreaks, inadequate application or deliberate evasion of cont ...199910633340
the transmission of prions to humans.the identification of new-variant creutzfeldt-jakob disease (nvcjd) in 1996 led to the proposal that this new disease was caused by the transmission of bovine spongiform encephalopathy (bse) to the human population. the ramifications of such a proposal have been extensive and profound, both politically and on the general public in the uk and other countries. patients with nvcjd exhibit a consistent set of clinicopathological features, and cases of nvcjd continue to be reported almost exclusively ...199910626542
analysis of the prion protein in primates reveals a new polymorphism in codon 226 (y226f).bovine spongiform encephalopathy has been epizootic in cows for the last two decades, and most probably causes variant creutzfeldt-jakob disease in humans. a thorough understanding of prion pathogenesis relies on suitable animal models. modeling the transmission of bse to primates is a crucial public health priority, necessary for determining the tissue distribution of the agent and for devising therapies. susceptibility of humans to bse is partly determined by polymorphism within the gene encod ...200212222676
creutzfeldt-jakob disease, new variant creutzfeldt-jakob disease, and bovine spongiform encephalopathy.creutzfeldt-jakob disease (cjd) is a subacute spongiform encephalopathy (sse) that is manifested by a variety of neurologic signs that usually include dementia, myoclonus, and an abnormal electroencephalogram (eeg). in 1996, a new variant of cjd (nvcjd) with a somewhat distinctive clinical presentation and neuropathology was reported in adolescents and young adults, a cohort of patients not normally affected with cjd. the appearance of nvcjd coincided temporally and geographically with the emerg ...199910517931
[a review of the current research on prions. the evidence suggests the possibility of transmission of the mad cow disease to humans].further evidence of the transmissibility of bovine spongiform encephalopathy (bse) across the species barrier from cow to man has been derived from epidemiological analysis and the characterisation of prion strains. recent research has shown the persistence of prions after experimental transmission to resistant murine species, and subclinical persistence in cows. the accumulation of pathological prion proteins in tonsils and appendix has been demonstrated prior to clinical confirmation of the pr ...19989854377
transmissible spongiform encephalopathies, hypotheses and food safety: an overview.the transmissible spongiform encephalopathies (tses) (in both humans and animals) have been reviewed with the principal focus on bovine spongiform encephalopathy (bse), its recent outbreak amongst cattle in the uk ('mad cow disease') and its sequelae. the possible reasons for this outbreak are discussed as well as a number of hypotheses reviewed for tses (e.g. prions, organophosphates, etc.) and current measures attendant with food safety and surveillance taken in the european union. it is gener ...19989695172
the mad cow problem in the uk: risk perceptions, risk management, and health policy development.mad cow disease or bovine spongiform encephalopathy (bse) is a fatal neurological disease of cattle first recognized in the united kingdom (uk) in 1986. until recently, the uk government considered the chance of a human becoming infected with the bse agent to be extremely remote. as a result of new developments, alarmist media attention, bureaucratic mishandling of the issues, scientific uncertainty, bickering among technical experts, and a dearth of easily assimilated and balanced information o ...19989670700
kuru and "new variant" cjd.acquired transmissible spongiform encephalopathies in humans include kuru (a disease which was associated with ritualistic cannibalism in papua new guinea), iatrogenic creutzfeldt-jakob disease and a newly recognized variant form of creutzfeldt-jakob disease (nvcjd). clinical and neuropathological features of nvcjd are reminiscent of kuru: early and progressive cerebellar ataxia and numerous characteristic kuru-type amyloid plaques surrounded by spongiform change. in contrast to typical cases of ...19979561604
[does mad cow disease cause the new variant of creutzfeldt-jakob disease?]. 19989528287
[transmissible spongiform encephalopathies in humans].transmissible spongiform encephalopathies (tse) are dementing diseases and have been known to affect humans for over 90 years. the most common of these is the sporadic form of creutzfeldt-jakob disease (scjd), followed by its familial (fcjd) and an iatrogenic (icjd) form. 1996 a variant of cjd (vcjd) has been described in the uk, of which so far 131 cases have been observed worldwide. specific biochemical and neuropathological signatures allow to distinguish between vcjd and scjd and lead to the ...200212585209
understanding creutzfeldt-jakob disease.the "mad cow disease" that decimated cattle in england has brought wide-spread attention to a similar disease in humans, creutzfeldt-jakob disease (cjd). this has led to concerns about the transmissibility and contagiousness of the infectious agent from possible cjd patients to health care workers and family members. despite these worries, the occurrence of cjd in the human population has remained stable over the years at an incidence of about one person per million in the united states populati ...19979416053
identification of a prion protein epitope modulating transmission of bovine spongiform encephalopathy prions to transgenic mice.there is considerable concern that bovine prions from cattle with bovine spongiform encephalopathy (bse) may have been passed to humans (hu), resulting in a new form of creutzfeldt-jakob disease (cjd). we report here the transmission of bovine (bo) prions to transgenic (tg) mice expressing boprp; one tg line exhibited incubation times of approximately 200 days. like most cattle with bse, vacuolation and astrocytic gliosis were confined in the brainstems of these tg mice. unexpectedly, mice expre ...19979405603
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
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
[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
bse and human prion disease. 19979337992
human prion diseases and bovine spongiform encephalopathy (bse).prion diseases are transmissible neurodegenerative disorders which affect a range of mammalian species. in humans they can be inherited and sporadic as well as acquired by exposure to human prions. prions appear to be composed principally of a conformational isomer of host-encoded prion protein and propagate by recruitment of cellular prion protein. recent evidence argues that prion protein can also encode disease phenotypes by differences in its conformation and glycosylation. such molecular an ...19979300662
nmr structure of the mouse prion protein domain prp(121-321).the 'protein only' hypothesis states that a modified form of normal prion protein triggers infectious neurodegenerative diseases, such as bovine spongiform encephalopathy (bse), or creutzfeldt-jakob disease (cjd) in humans. prion proteins are thought to exist in two different conformations: the 'benign' prpcform, and the infectious 'scrapie form', prpsc. knowledge of the three-dimensional structure of prpc is essential for understanding the transition to prpsc. the nuclear magnetic resonance (nm ...19968700211
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
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
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
genetic studies in relation to kuru: an overview.kuru is a subacute neurodegenerative disease presenting with limb ataxia, dysarthria, and a shivering tremor. the disease progress to complete motor and mental incapacity and death within 6 to 24 months. neuropathologically, a typical pattern of neuronal loss, astrocytic and microglial proliferation, characteristic "kuru-type" amyloid plaques, and prp deposits in the cerebral cortex and cerebellum are observed. kuru is the prototype of a group of human transmissible spongiform encephalopathies ( ...200415354868
examination of compact bone microdamage using back-scattered electron microscopy.a new staining technique using heavy metals (lead-uranyl acetate) has been developed to allow visualization of bone microdamage using both light microscopy and scanning electron microscopy operated in its back-scattered mode (bse). at the light microscopic level, the number of microcracks counted in sequential sections of human ribs is the same for both the traditional basic fuchsin method of differentially staining microcracks and the new lead-uranyl acetate procedure. with bse study, however, ...19947526878
thinking the unthinkable: alzheimer's, creutzfeldt-jakob and mad cow disease: the age-related reemergence of virulent, foodborne, bovine tuberculosis or losing your mind for the sake of a shake or burger.the possibility of the age-related reemergence of foodborne mycobacterium bovis (bovine tuberculosis) as a vector for creutzfeldt-jakob disease (cjd or human mad cow disease) and mad cow disease itself is real. the cdc reported last may of an outbreak of cjd linked to the consumption of meat contaminated "with the agent causing" bovine spongiform encephalopathy (bse) in a new jersey racetrack between the time frame 1995-2004. in the opinion of experts, ample justification exists for considering ...200515694685
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
total rate imaging with x-rays (trix)--a simple method of forming a non-projection x-ray image in the sem using an energy dispersive detector and its application to biological specimens.x-ray images can be formed in a conventional scanning electron microscope equipped with a si(li) energy dispersive spectrometer. all the x-ray events generated in the electron beam scanning process are synchronously displayed in the same manner as for dot maps. the quasi-digital image formed using total rate imaging with x-rays (trix) exhibits good gray scale contrast and is dependent on topography, orientation and atomic number. although this latter dependence is complex, it has been found usef ...19807423121
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
scanning electron microscopy in bone pathology: review of methods, potential and applications.this article reviews the applications of sem methods to human bone pathologies referring to studies made at ucl. we consider the methods which may be most suitable; these prove to be not "routine" in the context of most bio-medical applications of sem. valuable information can be obtained from a bone sample if its edges are ground flat, before making either a matrix surface preparation by washing away all the cells or a mineralizing front preparation, by also dissolving the osteoid-for which hyd ...19863544196
[british cattle plague--also a danger for man? bovine spongiform encephalopathy (bse)--scrapie disease]. 19902210580
recommendations of the international roundtable workshop on bovine spongiform encephalopathy.recommendations of the working party were summarized as follows: determine the status in all countries of their national cattle herds with respect to bse. attempt to develop a test to recognize bse-infected animals before they become clinically ill. establish procedures to prevent spread of bse agent into the cattle populations, especially by eliminating feeds containing rendered ruminant proteins. review the rendering processes, identify the sources and destinations of rendered products, and su ...19921348501
[potential risk of bovine spongiform encephalopathy (bse) to human beings and therapeutic approaches to prion disease]. 200212238161
risk assessment of bovine spongiform encephalopathy transmission through bone graft material derived from bovine bone used for dental applications.several commercial products are currently available for clinical application as bone graft substitutes. these products can be broadly classified into two categories: synthetic and natural. bovine bone is a popular source for several of the natural bone substitutes. the availability of bovine derived xenogenic bone substitutes has made it possible to avoid traumatic and expensive secondary surgery to obtain autogenous bone once thought essential for effective bone replacement. while autogenous bo ...199910505809
prions: a mystery unravelled?prions result in fatal degeneration of the central nervous system (cns) in the form of diseases known as transmissible spongiform encephalopathies (tses). the discovery in 1996 of a new variant of creutzfeldt-jakob disease (a human tse) and experimental confirmation that it is caused by the prion strain responsible for bovine spongiform encephalopathy (bse) has greatly spurred research in this field. the mechanism underlying prion propagation is now reasonably clear. prions multiply, in fact, by ...200212449682
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
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
bovine spongiform encephalopathy: an overview.bovine spongiform encephalopathy (bse), a novel disease of cattle first described in 1986, has now reached epidemic proportion in great britain with about 500 cases a week. the clinical, epidemiological, and pathological characteristics of bse are described. moreover, the etiopathogenetic mechanisms of spongiform encephalopathies are reviewed. legislative measures to prevent the spread of bse in italy and in other eec countries and to minimize the theoretical risk to man are reported.19921303043
lesion profiles and gliosis in the brainstem of 135 swiss cows with bovine spongiform encephalopathy (bse).lesion profiles are considered to be an important tool for the comparison of the various animal and human spongiform encephalopathies and to obtain information upon prion strain variations. histological and immunohistochemical reactions (prpsc, gfap) in 13 brain areas at 4 levels in the brainstem from 135 bse-positive and 45 bse-negative cases were retrospectively evaluated. in this retrospective study a lesion profile based on histological features was worked out on the basis of bse cases origi ...200717410969
[suppression of osteosarcoma in vitro by coexpression of antisense vegf165 cdna and thymidine kinase gene].to investigate the effect of vegf expression in osteosarcoma cell line and the target killing effect of hsv1-tk/gcv system on transfected osteosarcoma cells under hypoxia conditions.200717535687
prion diseases: epidemiology in man.prion disease in man was first described as creutzfeldt-jacob disease (cjd) in the 1920s. cjd may have three different origins: sporadic, familial, due to mutations in the prion gene, or infectious, due to iatrogenic exposure to infectious brain material. as an example of the latter, kuru, in papua new guinea, was a variant of cjd transmitted by cannibalism. between 1957 and 1982 more than 2500 died of kuru. sporadic cjd is the most common form of cjd and occurs with an incidence of around one p ...200212064251
postexposure prophylaxis against prion disease with a stimulator of innate immunity.the absence of an immune response to prions--the infectious agents of scrapie, bovine spongiform encephalopathy (bse), and creutzfeldt-jakob disease--might be related to the fact that these agents do not contain nucleic acids. we aimed to use cpg oligodeoxynucleotides, which have been shown to stimulate innate immunity, as a form of postexposure prophylaxis in mice. we inoculated healthy mice with brain homogenates from mice infected with the rml scrapie prion, and then injected cpg oligodeoxynu ...200212133662
preventive research and interventive research: in favour of to act rather than to react.conventional wisdom knows that "prevention is better than cure". however, in the many cases where we do not understand how to cure or intervent, prevention is not only better but may be the only way to promote public health. as the principal basis for preventive action, this paper advocates to focus more on preventive rather than on interventive research. preventive research, as defined here, aims to identify a determinant a in the environment which causes an undesirable health effect b in the h ...200212208213
could pets be of help in achieving health literacy? a media analysis demonstration study.this paper asks whether, when seeking to reach the public, interest in the health of pets merits consideration. our data set consisted of 128 items from canadian media coverage, 1996-2006, that dealt with bovine spongiform encephalopathy (bse) as well as with cats, dogs or both. three main messages regarding pet health and human health were identified: 'do not worry', 'do worry' and 'be cautious'. a minority of articles did not convey a pet health message or a human health message (6%), and cont ...200918359950
measuring prions causing bovine spongiform encephalopathy or chronic wasting disease by immunoassays and transgenic mice.there is increasing concern over the extent to which bovine spongiform encephalopathy (bse) prions have been transmitted to humans, as a result of the rising number of variant creutzfeldt-jakob disease (vcjd) cases. toward preventing new transmissions, diagnostic tests for prions in livestock have been developed using the conformation-dependent immunoassay (cdi), which simultaneously measures specific antibody binding to denatured and native forms of the prion protein (prp). we employed high-aff ...200212389035
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
cement lines of secondary osteons in human bone are not mineral-deficient: new data in a historical perspective.using qualitative backscattered electron (bse) imaging and quantitative energy dispersive x-ray (edx) spectroscopy, some investigators have concluded that cement (reversal) lines located at the periphery of secondary osteons are poorly mineralized viscous interfaces with respect to surrounding bone. this conclusion contradicts historical observations of apparent highly mineralized (or collagen-deficient) cement lines in microradiographs. such conclusions, however, may stem from unrecognized arti ...200516037990
[the prion hypothesis and the human prion diseases].our understanding of the pathogenesis of the transmissible spongiform encephalopathies (tse) has made terrific headway over the past 40 years and some scientists are even of the opinion that this group of diseases belongs to the neurodegenerative syndromes best understood. on the other hand, the investigation of tse has led to a multitude of unexpected and surprising results and consequently has initiated impassioned discussions among scientists. although the human forms of tse are very rare, th ...200211938572
early dysfunction of central 5-ht system in a murine model of bovine spongiform encephalopathy.the hypothesis of an early vulnerability of the serotonergic system to prion infection was investigated in a murine model of bovine spongiform encephalopathy (bse). behavioral tests targeted to 5-ht functions were performed in the course of infection to evaluate circadian activity, anxiety-like behavior, pain sensitivity and the 5-ht syndrome. the first behavioral change was a decrease in nocturnal activity detected at 30% of incubation time. further behavioral alterations including nocturnal hy ...200919285121
central nervous system tissue in meat products: an evaluation of risk, prevention strategies, and testing procedures.since the outbreak of bovine spongiform encephalopathy (bse) in the united kingdom in 1986 and its subsequent link to the human neurological disorder variant creutzfeldt-jakob disease (vcjd), presence of tissues from the central nervous system (cns) in meat products has been considered a public health concern and, thus, has been banned from entering the human food chain in many countries. despite this, potential can exist during harvesting to contaminate or cross-contaminate edible meat products ...200717900496
avian influenza in vietnam: chicken-hearted consumers?this study, based on quantitative and qualitative surveys conducted from july 2004 to september 2005, examines the perceptions of hanoi consumers and their reactions to the avian influenza epizootic (h5n1). hanoi consumers clearly link the risk of human contamination by the virus to the preparation and ingestion of poultry. during the first crisis, consumers reacted quickly and intensely (74% of them had already stopped eating poultry in january 2004). nevertheless, once the crisis abated, they ...200818419660
increased expression of water channel aquaporin 1 and aquaporin 4 in creutzfeldt-jakob disease and in bovine spongiform encephalopathy-infected bovine-prp transgenic mice.spongiform change is a cardinal feature in transmissible spongiform encephalopathies, including creutzfeldt-jakob disease (cjd) and bovine spongiform encephalopathy (bse). it is characterized by swelling of the neuronal processes and vacuolization of the neuropil, leading to increased intraneuronal water content. the present study examines, by gel electrophoresis and western blotting, the expression levels of the water channels aquaporin 1 (aqp1) and aquaporin 4 (aqp4) in the frontal cortex (are ...200616871401
factors governing speed of societal responses to threats: precision of definition of the threat may be more important than its anticipated likely severity.responses to two recent international public health threats, aids and bse, both exemplify missed opportunities for early intervention. they are in contrast to the response to the y2k computer issue, a threat of lesser-anticipated consequence but one that was more precisely defined. lessons from these experiences should inform the public health response to new threats, such as the emergence of multiple drug resistance in human pathogens.200212376075
variant creutzfeldt-jakob disease: an unfolding epidemic of misfolded proteins.variant creutzfeldt-jakob disease (vcjd) is an emerging infectious disease believed to be the human manifestation of bovine spongiform encephalopathy (bse). variant cjd belongs to a family of human and animal diseases called transmissible spongiform encephalopathies (tse). the pathogenesis of tse is not fully understood, but a modified form of a normal cellular protein plays a central role. current measures to control vcjd aim to prevent transmission of the infectious agent from animals to human ...200212410862
[m129v prnp gene polymorphism in castilla y león shows a similar distribution to other spanish regions and other european countries].it has been reported that the polymorphism m129v in the prnp gene modifies the phenotype in all the subtypes of prion diseases in humans. all cases diagnosed to date as suffering the human variant of mad cow disease (vcjd) carry the allele 129m. in the last five years five cases of vcjd have been reported in spain, three of them in castilla y león (in western spain). observation of differences in the genotypic frequency of this polymorphism in different populations prompted us to analyze the dis ...201020004419
autonomous nervous system with respect to dressing of cattle carcasses and its probable role in transfer of prp(res) molecules.pathogen prions are widely recognized as the causative agent in bovine spongiform encephalopathy (bse) and other transmissible spongiform encephalopathies. however, more research on the possible transmission mutes of this agent once it has reached the host is needed. there is evidence based on the anatomy and physiology of the autonomous nervous system (ans), as well as observations for different animal species, that the ans might be involved in the axonal drainage of pathogen prions toward the ...200312747703
[psycho-social stress in humans at mass slaughter of farm animals].animal epidemics are part of everyday life in animal husbandry, as are the psychosocial effects of the killing/slaughter of animals on the animal keeper. so here we are talking about everyday life observations of concerned people and veterinarians. but now, after the mass slaughter of contaminated animals in conjunction with bse and mks, society and the church have taught us to take a much closer look and we now realise that pathological traumatic states are to be considered almost universal con ...200312822253
copper binding in the prion protein.a conformational change of the prion protein is responsible for a class of neurodegenerative diseases called the transmissible spongiform encephalopathies that include mad cow disease and the human afflictions kuru and creutzfeldt-jakob disease. despite the attention given to these diseases, the normal function of the prion protein in healthy tissue is unknown. research over the past few years, however, demonstrates that the prion protein is a copper binding protein with high selectivity for cu( ...200414967054
identification of a second bovine amyloidotic spongiform encephalopathy: molecular similarities with sporadic creutzfeldt-jakob disease.transmissible spongiform encephalopathies (tses), or prion diseases, are mammalian neurodegenerative disorders characterized by a posttranslational conversion and brain accumulation of an insoluble, protease-resistant isoform (prp(sc)) of the host-encoded cellular prion protein (prp(c)). human and animal tse agents exist as different phenotypes that can be biochemically differentiated on the basis of the molecular mass of the protease-resistant prp(sc) fragments and the degree of glycosylation. ...200414970340
atypical transmissible spongiform encephalopathies in ruminants: a challenge for disease surveillance and control.since 1987, when bovine spongiform encephalopathy (bse) emerged as a novel disease in cattle, enormous efforts were undertaken to monitor and control the disease in ruminants worldwide. the driving force was its high economic impact, which resulted from trade restrictions and the loss of consumer confidence in beef products, the latter because bse turned out to be a fatal zoonosis, causing variant creutzfeldt-jakob disease in human beings. the ban on meat and bone meal in livestock feed and the ...201021088166
inactivation of transmissible spongiform encephalopathy agents in food products by ultra high pressure-temperature treatment.bovine spongiform encephalopathy (bse) contamination of the human food chain most likely resulted from nervous system tissue in mechanically recovered meat used in the manufacture of processed meats. the availability of effective decontamination methods for products considered at risk for bse or other transmissible spongiform encephalopathies (tses) would be an attractive safeguard to human health, but neither of the two proven inactivating methods, autoclaving or exposure to strong alkali or bl ...200616542885
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
bone regenerated via rhpdgf-bb and a deproteinized bovine bone matrix: backscattered electron microscopic element analysis.this study used backscattered electron microscopy (bse-sem) to analyze specimens in which bone was augmented both horizontally and vertically with a xenograft scaffold and recombinant human platelet-derived growth factor (rhpdgf-bb), with or without a resorbable collagen membrane. the study objective was to compare percentage weight and volume calcium-phosphorus ratios of regenerated bone and native bone and the nature of the bony contact with two different implant surfaces. examination of the n ...200718092448
animal serum-free culture conditions for isolation and expansion of multipotent mesenchymal stromal cells from human bm.multipotent mesenchymal stromal cells (msc) have become important tools in regenerative and transplantation medicine. rapidly increasing numbers of patients are receiving in vitro-expanded msc. culture conditions typically include fsc because human serum does not fully support growth of human msc in vitro (msc(fcs)). concerns regarding bse, other infectious complications and host immune reactions have fueled investigation of alternative culture supplements.200617050248
detection and characterization of proteinase k-sensitive disease-related prion protein with thermolysin.disease-related prp(sc) [pathogenic prp (prion protein)] is classically distinguished from its normal cellular precursor, prp(c)(cellular prp) by its detergent insolubility and partial resistance to proteolysis. although molecular diagnosis of prion disease has historically relied upon detection of protease-resistant fragments of prp(sc) using pk (proteinase k), it is now apparent that a substantial fraction of disease-related prp is destroyed by this protease. recently, thermolysin has been ide ...200818684106
experimental interspecies transmission studies of the transmissible spongiform encephalopathies to cattle: comparison to bovine spongiform encephalopathy in cattle.prion diseases or transmissible spongiform encephalopathies (tses) of animals include scrapie of sheep and goats; transmissible mink encephalopathy (tme); chronic wasting disease (cwd) of deer, elk and moose; and bovine spongiform encephalopathy (bse) of cattle. the emergence of bse and its spread to human beings in the form of variant creutzfeldt-jakob disease (vcjd) resulted in interest in susceptibility of cattle to cwd, tme and scrapie. experimental cross-species transmission of tse agents p ...201121908269
on the question of sporadic or atypical bovine spongiform encephalopathy and creutzfeldt-jakob disease.strategies to investigate the possible existence of sporadic bovine spongiform encephalopathy (bse) require systematic testing programs to identify cases in countries considered to have little or no risk of orally acquired disease or to detect a stable occurrence of atypical cases in countries in which orally acquired disease is disappearing. to achieve 95% statistical confidence that the prevalence for sporadic bse is no greater than 1 per million (i.e., the annual incidence of sporadic creutzf ...200617326930
the significance of using pooled human serum in human articular cartilage tissue engineering.animal serum is commonly used in chondrocytes culture expansion to promote cell proliferation and shorten the time lag before new tissue reconstruction is possible. however, animal serum is not suitable for regeneration of clinical tissue because it has potential risk of viral and prion related disease transmission particularly mad cow disease and foreign protein contamination that can stimulate immune reaction leading to graft rejection. in this context, human serum as homologous supplement has ...200415468795
bovine spongiform encephalopathy statement of possible relation with new variant creutzfeldt-jakob disease: effects on the welfare of united kingdom cattle.although measures to control bovine spongiform encephalopathy (bse) had been in force in the united kingdom for many years and had resulted in a marked decline in clinical cases, the announcement by the secretary of state for health on march 20, 1996, that a new variant form of creutzfeldt-jakob disease may be linked with exposure to bse, resulted in the introduction of several new control measures. these measures included a scheme banning human consumption of meat from cattle who were more than ...199816363943
an evaluation of united kingdom environmental bovine spongiform encephalopathy risk a member of the group of diseases known as transmissible spongiform encephalopathies (tses), bovine spongiform encephalopathy (bse) has been causally associated with a new variant of creutzfeldt-jakob disease (vcjd) in humans. given the many uncertainties on the transmission and persistence of tse pathogens in the environment, quantitative assessment of risks to humans and animals continues to remain a public health issue. this paper reviews quantitative bse risk assessments undertaken in the ...200516639897
variant cjd (vcjd) and bovine spongiform encephalopathy (bse): 10 and 20 years on: part 2.up until february 2006, variant cjd (vcjd), the human disease associated with transmission of bse from cattle, has been confirmed in 160 patients resident in the uk and 28 elsewhere, some of whom have never visited the uk. cases have been reported in france (16 cases), ireland (3), usa (2), canada, italy, japan, the netherlands, portugal, saudi arabia and spain (1 each). the presumed main period of hazard for ingestion of the bse agent in bovine products in the uk is 1984-89, or perhaps up to 19 ...200616823692
harvard study finds bse poses little threat to u.s. consumers, agriculture. 200211829250
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