Publications
| Title | Abstract | Year Filter | PMID(sorted descending) Filter |
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| prions of ruminants show distinct splenotropisms in an ovine transgenic mouse model. | transmissible agents involved in prion diseases differ in their capacities to target different regions of the central nervous system and lymphoid tissues, which are also host-dependent. | 2010 | 20436680 |
| ovine reference materials and assays for prion genetic testing. | genetic predisposition to scrapie in sheep is associated with several variations in the peptide sequence of the prion protein gene (prnp). dna-based tests for scoring prnp codons are essential tools for eradicating scrapie and for evaluating rare alleles for increased resistance to disease. in addition to those associated with scrapie, there are dozens more prnp polymorphisms that may occur in various flocks. if not accounted for, these sites may cause base-pair mismatching with oligonucleotides ... | 2010 | 20433741 |
| iron content of ferritin modulates its uptake by intestinal epithelium: implications for co-transport of prions. | the spread of chronic wasting disease (cwd) in the deer and elk population has caused serious public health concerns due to its potential to infect farm animals and humans. like other prion disorders such a sporadic creutzfeldt-jakob-disease of humans and mad cow disease of cattle, cwd is caused by prp-scrapie (prpsc), a beta-sheet rich isoform of a normal cell surface glycoprotein, the prion protein (prpc). since prpsc is sufficient to cause infection and neurotoxicity if ingested by a suscepti ... | 2010 | 20429907 |
| glycosylphosphatidylinositol anchor analogues sequester cholesterol and reduce prion formation. | a hallmark of prion diseases is the conversion of the host-encoded prion protein (prp(c) where c is cellular) into an alternatively folded, disease-related isoform (prp(sc), where sc is scrapie), the accumulation of which is associated with synapse degeneration and ultimately neuronal death. the formation of prp(sc) is dependent upon the presence of prp(c) in specific, cholesterol-sensitive membrane microdomains, commonly called lipid rafts. prp(c) is targeted to these lipid rafts because it is ... | 2010 | 20427265 |
| detection of prpsc in lung and mammary gland is favored by the presence of visna/maedi virus lesions in naturally coinfected sheep. | there are few reports on the pathogenesis of scrapie (sc) and visna/maedi virus (vmv) coinfections. the aim of this work was to study in vivo as well as post mortem both diseases in 91 sheep. diagnosis of sc and vmv infections allowed the distribution of animals into five groups according to the presence (+) or absence (-) of infection by sc and vmv: sc-/vmv-, sc-/vmv+, sc+/vmv- and sc+/vmv+. the latter was divided into two subgroups, with and without vmv-induced lymphoid follicle hyperplasia (l ... | 2010 | 20423698 |
| the evolution of internet-based map server applications in the united states department of agriculture, veterinary services. | the internet is used increasingly as an effective means of disseminating information. for the past five years, the united states department of agriculture (usda) veterinary services (vs) has published animal health information in internet-based map server applications, each oriented to a specific surveillance or outbreak response need. using internet-based technology allows users to create dynamic, customised maps and perform basic spatial analysis without the need to buy or learn desktop geogra ... | 2007 | 20422551 |
| the physical relationship between infectivity and prion protein aggregates is strain-dependent. | prions are unconventional infectious agents thought to be primarily composed of prp(sc), a multimeric misfolded conformer of the ubiquitously expressed host-encoded prion protein (prp(c)). they cause fatal neurodegenerative diseases in both animals and humans. the disease phenotype is not uniform within species, and stable, self-propagating variations in prp(sc) conformation could encode this 'strain' diversity. however, much remains to be learned about the physical relationship between the infe ... | 2010 | 20419156 |
| ovine prp genotype is linked with lesion profile and immunohistochemistry patterns after primary transmission of classical scrapie to wild-type mice. | it is currently believed that primary transmission of classical scrapie to wild-type mice is inefficient and characterized by low attack rates and variable incubation periods and lesion profiles. consequently, strain characterization of classical scrapie in these mice relies on subpassage. the aim of this study was to perform a retrospective analysis of lesion profiles and immunohistochemistry patterns after transmission of a large number of classical scrapie sources to wild-type mice and to inv ... | 2010 | 20418778 |
| anti-prp antibodies detected at terminal stage of prion-affected mouse. | the causative agent of prion diseases is the pathological isoform (prpsc) of the host-encoded cellular prion protein (prpc). prpsc has an identical amino acid sequence to prpc; thus, it has been assumed that an immune response against prpsc could not be found in prion-affected animals. in this study, we found the anti-prion protein (prp) antibody at the terminal stage of mouse scrapie. several sera from mice in the terminal stage of scrapie reacted to the recombinant mouse prp (rmprp) molecules ... | 2010 | 20417929 |
| fluorescence spectroscopy of the retina for diagnosis of transmissible spongiform encephalopathies. | the feasibility of exploiting fluorescence spectra of the eye for diagnosis of transmissible spongiform encephalopathies (tses) was examined. retinas from scrapie-positive sheep were compared with scrapie-negative sheep using fluorescence spectroscopy, and distinct differences in the fluorescence intensity and spectroscopic signatures were observed. the characteristic fluorescent signatures are thought to be the result of an accumulation of lipofuscin in the retina. it appears that the eye, in p ... | 2010 | 20411920 |
| influence of surface functionality of poly(propylene imine) dendrimers on protease resistance and propagation of the scrapie prion protein. | accumulation of prp(sc), an insoluble and protease-resistant pathogenic isoform of the cellular prion protein (prp(c)), is a hallmark in prion diseases. branched polyamines, including ppi (poly(propylene imine)) dendrimers, are able to remove protease resistant prp(sc) and abolish infectivity, offering possible applications for therapy. these dendrimer types are thought to act through their positively charged amino surface groups. in the present study, the molecular basis of the antiprion activi ... | 2010 | 20405854 |
| prions are secreted into the oral cavity in sheep with preclinical scrapie. | a major concern in prion disease transmission is the spread of the disease agent by means of secretions and excretions. we analyzed buccal swab samples obtained from preclinical scrapie-infected sheep by concentrating the collected prions on silicon dioxide, followed by amplification by serial protein misfolding cyclic amplification. data clearly demonstrate that prions are present in buccal swab samples from sheep with a vrq/vrq prnp genotype during preclinical scrapie infection. these data des ... | 2010 | 20402590 |
| surveillance and simulation of bovine spongiform encephalopathy and scrapie in small ruminants in switzerland. | after bovine spongiform encephalopathy (bse) emerged in european cattle livestock in 1986 a fundamental question was whether the agent established also in the small ruminants' population. in switzerland transmissible spongiform encephalopathies (tses) in small ruminants have been monitored since 1990. while in the most recent tse cases a bse infection could be excluded, for historical cases techniques to discriminate scrapie from bse had not been available at the time of diagnosis and thus their ... | 2010 | 20398417 |
| characterization of atypical scrapie cases from great britain in transgenic ovine prp mice. | twenty-four atypical scrapie cases from sheep with different prion protein genotypes from great britain were transmitted to transgenic tg338 and/or tgshpxi mice expressing sheep prp alleles, but failed to transmit to wild-type mice. mean incubation periods were 200-300 days in tg338 mice and 300-500 days in tgshpxi mice. survival times in c57bl/6 and vm/dk mice were >700 days. western blot analysis of mouse brain samples revealed similar multi-band, protease-resistant prion protein (prp(res)) pr ... | 2010 | 20392900 |
| a novel anti-prion protein monoclonal antibody and its single-chain fragment variable derivative with ability to inhibit abnormal prion protein accumulation in cultured cells. | mabs t1 and t2 were established by immunizing prp gene ablated mice with recombinant moprp of residues 121-231. both mabs were cross-reactive with prp from hamster, sheep, cattle and deer. a linear epitope of mab t1 was identified at residues 137-143 of moprp and buried in prp(c) expressed on the cell surface. mab t1 showed no inhibitory effect on accumulation of prp(sc) in cultured scrapie-infected neuroblastoma (scn2a) cells. in contrast, mab t2 recognized a discontinuous epitope ranged on, or ... | 2010 | 20377745 |
| evaluation of prion deposits and microglial activation in scrapie-infected mice using molecular imaging probes. | a characteristic of prion diseases which affect both animals and humans is the aggregation of prp amyloid fibrils in the brain, associated with a chronic inflammatory response dominated by microglial activation. in this study, we hypothesised that specific ligands of the 18-kda translocator protein (tspo) would be effective in the evaluation of microglial activation related to prp(sc) deposits in prion disease. | 2010 | 20376566 |
| prp-specific camel antibodies with the ability to immunodetect intracellular prion protein. | although there is currently no effective treatment for prion diseases, significant advances have been made in suppressing its progress, using antibodies that block the conversion of prp(c) into prp(sc). in order to be effective in treating individuals that have prion diseases, antibodies must be capable of arresting disease in its late stages. this requires the development of antibodies with higher affinity for prp(sc) and systems for effective translocation of antibodies across the blood-brain ... | 2010 | 20375226 |
| pathogenesis of natural goat scrapie: modulation by host prnp genotype and effect of co-existent conditions. | after detection of a high prevalence of scrapie in a large dairy goat herd, 72 infected animals were examined by immunohistochemistry with prion protein (prp) antibody bar224 to study the pathogenesis of the infection. tissues examined included the brain and thoracic spinal cord (tsc), a wide selection of lymphoreticular system (lrs) tissues, the distal ileum and its enteric nervous system (ens), and other organs, including the mammary gland. the whole open reading frame of the prnp gene was seq ... | 2010 | 20374697 |
| a novel method for preclinical detection of prpsc in blood. | in this study, we demonstrate that a moderate amount of protein misfolding cyclic amplification (pmca) coupled to a novel surround optical fibre immunoassay (sofia) detection scheme can be used to detect the disease-associated form of the prion protein (prp(sc)) in protease-untreated plasma from preclinical and clinical scrapie sheep, and white-tailed deer with chronic wasting disease, following natural and experimental infection. prp(sc), resulting from a conformational change of the normal (ce ... | 2010 | 20357038 |
| changes of tau profiles in brains of the hamsters infected with scrapie strains 263 k or 139 a possibly associated with the alteration of phosphate kinases. | phospho-tau deposition has been described in a rare genetic human prion disease, gerstmann-sträussler-scheinker syndrome, but is not common neuropathological picture for other human and animal transmissible spongiform encephalopathies (tses). this study investigated the possible changes of tau and phosphorylated tau (p-tau, at ser396, ser404, and ser202/thr205) in scrapie experimental animals. | 2010 | 20356412 |
| methodological approach for substantiating disease freedom in a heterogeneous small population. application to ovine scrapie, a disease with a strong genetic susceptibility. | demonstrating disease freedom is becoming important in different fields including animal disease control. most methods consider sampling only from a homogeneous population in which each animal has the same probability of becoming infected. in this paper, we propose a new methodology to calculate the probability of detecting the disease if it is present in a heterogeneous population of small size with potentially different risk groups, differences in risk being defined using relative risks. to ca ... | 2010 | 20347494 |
| atypical/nor98 scrapie in the basque country: a case report of eight outbreaks. | since 2002, an active surveillance program for transmissible spongiform encephalopathy in small ruminants in european union countries allowed identification of a considerable number of atypical cases with similarities to the previously identified atypical scrapie cases termed nor98. | 2010 | 20346155 |
| a camelid anti-prp antibody abrogates prp replication in prion-permissive neuroblastoma cell lines. | the development of antibodies effective in crossing the blood brain barrier (bbb), capable of accessing the cytosol of affected cells and with higher affinity for prp(sc) would be of paramount importance in arresting disease progression in its late stage and treating individuals with prion diseases. antibody-based therapy appears to be the most promising approach following the exciting report from white and colleagues, establishing the "proof-of-principle" for prion-immunotherapy. after passive ... | 2010 | 20339552 |
| application of a fluorescent dual stain to assess decontamination of tissue protein and prion amyloid from surgical stainless steel during simulated washer-disinfector cycles. | current world health organization guidelines pertaining to the reprocessing of surgical instruments in the face of potential iatrogenic transmission of creutzfeldt-jakob disease (icjd) are incompatible for the vast majority of devices. this has led to the advent of a range of new decontamination measures. even without the implementation of these new procedures, the incidence of proven icjd through surgery remains low. in this study, existing decontamination processes in sterile service departmen ... | 2010 | 20303614 |
| spreading of prions from the immune to the peripheral nervous system: a potential implication of dendritic cells. | the implication of dendritic cells (dcs) in the peripheral spreading of prions has increased in the last few years. it has been recently described that dcs can transmit prions to primary neurons from the central nervous system. in order to improve the understanding of the earliest steps of prion peripheral neuroinvasion, we studied, using an in vitro model, the effect of exposing primary peripheral neurons to scrapie-infected lymphoid cells. thanks to this system, there is evidence that bone mar ... | 2010 | 20238136 |
| fatal transmissible amyloid encephalopathy: a new type of prion disease associated with lack of prion protein membrane anchoring. | prion diseases are fatal neurodegenerative diseases of humans and animals characterized by gray matter spongiosis and accumulation of aggregated, misfolded, protease-resistant prion protein (prpres). prpres can be deposited in brain in an amyloid-form and/or non-amyloid form, and is derived from host-encoded protease-sensitive prp (prpsen), a protein normally anchored to the plasma membrane by glycosylphosphatidylinositol (gpi). previously, using heterozygous transgenic mice expressing only anch ... | 2010 | 20221436 |
| the natural atypical scrapie phenotype is preserved on experimental transmission and sub-passage in prnp homologous sheep. | atypical scrapie was first identified in norwegian sheep in 1998 and has subsequently been identified in many countries. retrospective studies have identified cases predating the initial identification of this form of scrapie, and epidemiological studies have indicated that it does not conform to the behaviour of an infectious disease, giving rise to the hypothesis that it represents spontaneous disease.however, atypical scrapie isolates have been shown to be infectious experimentally, through i ... | 2010 | 20219126 |
| the genetics of prion diseases. | prion diseases are a rare group of fatal neurodegenerative disorders of humans and animals that manifest primarily as progressive dementia and ataxia. unique to these diseases is the prion, a misfolded isoform of the prion protein that can transmit disease from cell to cell or host to host by associating with, and transforming, normal prion protein into the misfolded isoform (the pathogenic scrapie-inducing form). although the majority of cases occur on a sporadic basis, and rarely result from e ... | 2010 | 20216075 |
| a single step multiplex immunofluorometric assay for differential diagnosis of bse and scrapie. | although there is no evidence that the european sheep population has been infected with bovine spongiform encephalopathy (bse), distinguishing this from scrapie is paramount, given the association between bse exposure and the human transmissible spongiform encephalopathy (tse), variant creutzfeldt-jakob disease. the capability to differentially diagnose tses in sheep is thus essential in order to safeguard the food chain and human health. biochemical methods for differentiating bse and scrapie a ... | 2010 | 20214905 |
| prion infection of differentiated neurospheres. | until now only a few cell lines have been proved able to propagate prions and only limited prion strains have been replicated in cell models. neurosphere lines isolated from the brains of mice at embryonic day 14 grow as aggregates and contain cns stem cells. others authors have previously reported that cultured neurospheres expressing cellular prion protein (prp(c)) can be infected with prions. as potential neural progenitors the neurosphere cultures are supposed to differentiate into neurons a ... | 2010 | 20206206 |
| disease-associated prion protein in the dental tissue of mice infected with scrapie. | transmissible spongiform encephalopathies (tses) induce fatal neurodegenerative diseases in man and animals. the present study demonstrates immunohistochemically the presence of disease-associated prion protein (prp(sc)) in the epithelial cell rests of malassez (erm) of mice experimentally infected with me7 scrapie by the intracerebral route. mouse bioassay of scrapie-infected dental tissue revealed prolonged incubation periods, suggesting that there are relatively low amounts of infectious agen ... | 2010 | 20202648 |
| monitoring of clinical signs in goats with transmissible spongiform encephalopathies. | as there is limited information about the clinical signs of bse and scrapie in goats, studies were conducted to describe the clinical progression of scrapie and bse in goats and to evaluate a short clinical protocol for its use in detecting scrapie-affected goats in two herds with previously confirmed scrapie cases. clinical assessments were carried out in five goats intracerebrally infected with the bse agent as well as five reported scrapie suspects and 346 goats subject to cull from the two h ... | 2010 | 20202205 |
| real-time visualization of prion transport in single live cells using quantum dots. | prion diseases are fatal neurodegenerative disorders resulting from structural conversion of the cellular isoform of prp(c) to the infectious scrapie isoform prp(sc). it is believed that such structural alteration may occur within the internalization pathway. however, there is no direct evidence to support this hypothesis. employing quantum dots (qds) as a probe, we have recorded a real-time movie demonstrating the process of prion internalization in a living cell for the first time. the entire ... | 2010 | 20193663 |
| tracing conformational transition of abnormal prion proteins during interspecies transmission by using novel antibodies. | conformational differences in abnormal prion proteins (prp(sc)) have been postulated to produce different prion phenotypes. during the interspecies transmission of prions, the conformation of prp(sc) may change with passage; however, little is known about the mechanism of prp(sc) transition. in this study, novel prp(sc)-specific monoclonal antibodies (mabs) were developed that could detect the prp(sc) of mouse but not that of sheep. by using these mabs, we attempted to examine prp(sc) accumulate ... | 2010 | 20177064 |
| manganese upregulates cellular prion protein and contributes to altered stabilization and proteolysis: relevance to role of metals in pathogenesis of prion disease. | prion diseases are fatal neurodegenerative diseases resulting from misfolding of normal cellular prion (prp(c)) into an abnormal form of scrapie prion (prp(sc)). the cellular mechanisms underlying the misfolding of prp(c) are not well understood. since cellular prion proteins harbor divalent metal-binding sites in the n-terminal region, we examined the effect of manganese on prp(c) processing in in vitro models of prion disease. exposure to manganese significantly increased prp(c) levels both in ... | 2010 | 20176619 |
| the role of mathematical modelling in understanding the epidemiology and control of sheep transmissible spongiform encephalopathies: a review. | to deal with the incompleteness of observations and disentangle the complexities of transmission much use has been made of mathematical modelling when investigating the epidemiology of sheep transmissible spongiform encephalopathies (tse) and, in particular, scrapie. importantly, these modelling approaches allow the incidence of clinical disease to be related to the underlying prevalence of infection, thereby overcoming one of the major difficulties when studying these diseases. models have been ... | 2010 | 20175963 |
| putative emergence of classical scrapie in a background of enzootic atypical scrapie. | active transmissible spongiform encephalopathy (tse) surveillance in small ruminants across europe was implemented in 2002 following the epizootic of bovine spongiform encephalopathy. here, we report the potential emergence of classical scrapie in portugal, in a background of enzootic atypical scrapie. between 2003 and 2008, 375,459 small ruminants were screened in total, with 328 animals confirmed positive for nor98 atypical scrapie. during this period, the prevalence rate of atypical scrapie f ... | 2010 | 20164262 |
| structure of the prion protein and its gene: an analysis using bioinformatics and computer simulation. | prion protein (prp) gene encodes cellular prp (prpc), a glycosylphosphatidylinositol (gpi)-anchored cell membrane protein indispensable for infections of prion, which causes creutzfeldt-jakob disease (cjd) in humans, bovine spongiform encephalopathy (bse) in cattle, and scrapie in sheep. although prpc is known to be converted into an abnormal isoform (prpsc) upon prion infection and play an important role in prion diseases, the mechanisms involved remain unclear, partly due to the insolubility o ... | 2010 | 20158453 |
| vesicle permeabilization by purified soluble oligomers of prion protein: a comparative study of the interaction of oligomers and monomers with lipid membranes. | the conversion of normal cellular prion protein (prp) into its pathological isoform, scrapie prp, may occur at the cell surface or, more probably, in late endosomes. the early events leading to the structural conversion of prp appear to be related to the presence of more or less stable soluble oligomers, which might mediate neurotoxicity. in the current study, we investigate the interaction of alpha-rich prp monomers and beta-rich size-exclusion-chromatography-purified prp oligomers with lipid m ... | 2010 | 20156446 |
| characterization of strains of ovine transmissible spongiform encephalopathy with a short prpd profiling method. | scrapie is the transmissible spongiform encephalopathy (tse) that naturally affects sheep and goats; these species are also susceptible to experimental infection with the bovine spongiform encephalopathy (bse) agent. discrimination between different strains of sheep scrapie and ovine bse has been achieved by descriptive and quantitative profiling of deposits of the disease-associated prion protein (prpd) in different areas of the brain, but this process is time-consuming and difficult to standar ... | 2010 | 20153480 |
| the prevalence of atypical scrapie in sheep from positive flocks is not higher than in the general sheep population in 11 european countries. | during the last decade, active surveillance for transmissible spongiform encephalopathies in small ruminants has been intensive in europe. in many countries this has led to the detection of cases of atypical scrapie which, unlike classical scrapie, might not be contagious. eu legislation requires, that following detection of a scrapie case, control measures including further testing take place in affected flocks, including the culling of genotype susceptible to classical scrapie. this might resu ... | 2010 | 20137097 |
| assessing the role of oxidized methionine at position 213 in the formation of prions in hamsters. | prions are infectious proteins that are able to recruit a normal cellular prion protein and convert it into a prion. the mechanism of this conversion is unknown. detailed analysis of the normal cellular prion protein and a corresponding prion has shown they possess identical post-translational modifications and differ solely in conformation. recent work has suggested that the oxidized form of the methionine at position 213 (met213) plays a role in the conversion of the normal cellular prion prot ... | 2010 | 20121218 |
| agent-specific shadoo responses in transmissible encephalopathies. | transmissible spongiform encephalopathies (tse) are neurodegenerative diseases caused by an infectious agent with viral properties. host prion protein (prp), a marker of late stage tse pathology, is linked to a similar protein called shadoo (sho). sho is reduced in mice infected with the rml scrapie agent, but has not been investigated in other tses. although prp is required for infection by tse agents, it is not known if sho is similarly required. presumably sho protects cells from toxic effect ... | 2010 | 20112073 |
| caprine prnp polymorphisms at codons 171, 211, 222 and 240 in a greek herd and their association with classical scrapie. | the association between prnp variation and scrapie incidence was investigated in a highly affected greek goat herd. four mutations were identified at codons 171q/r, 211r/q, 222q/k and 240p/s. lysine at codon 222 was found to be associated with the protection from natural scrapie (p=0.0111). glutamine at codon 211 was observed in eight animals, all of them being scrapie-negative, indicating a possible protective role of this polymorphism although statistical analysis failed to support it (p=0.107 ... | 2010 | 20107013 |
| low density subcellular fractions enhance disease-specific prion protein misfolding. | the production of prion particles in vitro by amplification with or without exogenous seed typically results in infectivity titers less than those associated with prp(sc) isolated ex vivo and highlights the potential role of co-factors that can catalyze disease-specific prion protein misfolding in vivo. we used a cell-free conversion assay previously shown to replicate many aspects of transmissible spongiform encephalopathy disease to investigate the cellular location of disease-specific co-fact ... | 2010 | 20106973 |
| rapid chromatographic immunoassay study of brain prpsc distribution in classical scrapie. | in the current study, a rapid chromatographic immunoassay submitted for registration in europe was used to analyze prp(sc) in 13 different areas of brain from 10 confirmed classical scrapie cases. the levels of prp(sc) in the different areas of brain were plotted to draw a brain prp(sc) distribution curve. this curve was compared with the brain prp(sc) distribution curve obtained from immunoblotting and immunohistochemistry tests on the same samples. the distribution of prp(sc) in different area ... | 2010 | 20093689 |
| prp gene polymorphisms in cyprus goats and their association with resistance or susceptibility to natural scrapie. | in contrast to scrapie in sheep, the genetic basis of susceptibility to scrapie in goats is not well understood. to study the association of prion protein (prp) alleles with susceptibility to scrapie in goats in cyprus, the coding sequence of the caprine prp gene was determined in 717 goats, including 218 scrapie positive animals. several novel polymorphisms were detected, such as a novel octarepeat variant and a stop codon mutation. amino acids at codons 146 and 154 were associated with suscept ... | 2011 | 20093056 |
| differentiating blood samples from scrapie infected and non-infected hamsters by detecting disease-associated prion proteins using multimer detection system. | this communication describes the application of a modified sandwich enzyme-linked immunosorbent assay (elisa), termed multimer detection system (mds) for the detection of disease-associated multimeric forms of the prion protein (prpd) in hamster blood. prpd was detected in plasma of prion-affected hamsters while mds revealed no prpd in identically-treated plasma of healthy animals. this is the first report of a single elisa- based immune detection of prpd from blood samples. | 2010 | 20085753 |
| association of endothelial nitric oxide synthase and mitochondrial dysfunction in the hippocampus of scrapie-infected mice. | the elevation of nitric oxide (no) within the central nervous system (cns) is known to be associated with the pathogenesis of neurodegenerative diseases such as hiv-associated dementia (had), brain ischemia, parkinson's disease, and alzheimer's disease. no is enzymatically formed by the enzyme nitric oxide synthase (nos). there are two forms of nos, the constitutive and the inducible form. the constitutive form is present in endothelial cells (enos) and neurons (nnos). the inducible form (inos) ... | 2010 | 20082297 |
| consequences of dietary manganese and copper imbalance on neuronal apoptosis in a murine model of scrapie. | copper and manganese levels are altered in mice both lacking prpc and prion-infected brains. the aim of this study was to analyse the effects of manganese and copper imbalance on neuronal apoptosis in a scrapie-infected tga20 mouse model. | 2010 | 20070537 |
| beta-sheet constitution of prion proteins. | structural information regarding normal prion protein (prp(c)) and the scrapie isoform (prp(sc)) is of vital importance for elucidating the pathogenesis of prion diseases (pds). despite successful determination of the three-dimensional structures of prp(c), the structural details of prp(sc) remain elusive. nevertheless, accumulated evidence indicates that beta-sheets comprise the basic building blocks of prp(sc). consensus has been reached about the beta-sheet constitution of the n-terminus of p ... | 2010 | 20060302 |
| demographic characteristics of scrapie-affected holdings identified by active and passive surveillance schemes in great britain: 2002-2005. | several surveillance techniques have been used to quantify the prevalence of both classical and atypical scrapie in british sheep, namely the recording of clinical suspects (rc) and the testing of animals slaughtered at abattoir (as) or reported as fallen stock (fs). any estimate of prevalence based on a particular source is likely to have been affected by demographic differences in the populations sampled. in this study, the demographic characteristics of scrapie-affected holdings detected by e ... | 2011 | 20056463 |
| degradation and destabilization of abnormal prion protein using alkaline detergents and proteases. | there is a limited number of reports regarding detergents and proteases inactivating, degrading, or destabilizing abnormal prion protein (prpsc). in the present study, the effect of alkaline detergents and proteases on the breakdown of prpsc in the absence of proteinase k (pk) (degradation) and the presence of pk (destabilization) was investigated. prpsc from brain homogenate of terminally-diseased mice infected with the chandler strain of scrapie was used as a substrate. a surfactant-free alkal ... | 2010 | 20043137 |
| amino acid conditions near the gpi anchor attachment site of prion protein for the conversion and the gpi anchoring. | prion protein (prp) is a glycosylphosphatidylinositol (gpi)-anchored protein, and the c-terminal gpi anchor signal sequence (gpi-ss) of prp is cleaved before gpi anchoring. however, mutations near the gpi anchor attachment site (the omega site) in the gpi-ss have been recognized in human genetic prion diseases. moreover, the omega site of prp has not been identified except hamster, though it is known that amino acid restrictions are very severe at the omega and omega+2 sites in other gpi-anchore ... | 2010 | 20040362 |
| infection of cell lines with experimental and natural ovine scrapie agents. | mouse bioassay remains the gold standard for determining proof of infectivity, strain type, and infectious titer estimation in prion disease research. the development of an approach using ex vivo cell-based assays remains an attractive alternative, both in order to reduce the use of mice and to hasten results. the main limitation of a cell-based approach is the scarcity of cell lines permissive to infection with natural transmissible spongiform encephalopathy strains. this study combines two adv ... | 2010 | 20032176 |
| co-existence of classical scrapie and nor98 in a sheep from an italian outbreak. | nor98 is an atypical scrapie strain characterized by a molecular pattern and brain distribution of the pathological prion protein (prp(sc)) different from classical scrapie. in italy, 69 atypical cases have been identified so far and all were characterized as nor98 strain. in this paper we report an unusual case in a sheep which showed immunohistochemical and molecular features of prp(sc) different from the other atypical cases. the sheep was from an outbreak where the index and the other four c ... | 2010 | 20031179 |
| effect of scrapie on the stability of housekeeping genes. | scrapie is the archetype of prion diseases, fatal neurodegenerative disorders that affect humans and animals. gene expression analysis of normal and infected sheep may provide clues to clarify the molecular mechanisms involved in the neuropathology of these diseases. real time quantitative pcr has become a powerful and accurate technique for examination of transcription patterns in different biological conditions. one of the critical steps in the comparison of transcription profiles is the selec ... | 2010 | 20024782 |
| involvement of peptidylarginine deiminase-mediated post-translational citrullination in pathogenesis of sporadic creutzfeldt-jakob disease. | peptidylarginine deiminases (pads)-mediated post-translational citrullination processes play key roles in protein functions and structural stability through the conversion of arginine to citrulline in the presence of excessive calcium concentrations. in brain, pad2 is abundantly expressed and can be involved in citrullination in disease. recently, we have reported pathological characterization of pad2 and citrullinated proteins in scrapie-infected mice, but the implication of protein citrullinat ... | 2010 | 20013286 |
| dramatic reduction of prp c level and glycosylation in peripheral nerves following prp knock-out from schwann cells does not prevent transmissible spongiform encephalopathy neuroinvasion. | expression of the prion protein (prp(c)) is a requirement for host susceptibility to the transmissible spongiform encephalopathies (tses) and thought to be necessary for the replication and transport of the infectious agent. the mechanism of tse neuroinvasion is not fully understood, although the routing of infection has been mapped through the peripheral nervous system (pns) and schwann cells have been implicated as a potential conduit for transport of the tse infectious agent. to address wheth ... | 2009 | 20007469 |
| evaluation of removal of prion infectivity from red blood cells with prion reduction filters using a new rapid and highly sensitive cell culture-based infectivity assay. | the clearance of infectious prions from biologic fluids is usually quantified by bioassays based on intracerebral inoculation of hamsters or mice; these tests are slow, cumbersome, imprecise, and very expensive. in the present study we describe the use of a new and highly sensitive cell culture-based infectivity assay to evaluate the performance of several prion removal prototype filters. | 2010 | 20003057 |
| scrapie affects the maturation cycle and immune complex trapping by follicular dendritic cells in mice. | transmissible spongiform encephalopathies (tses) or prion diseases are infectious neurological disorders of man and animals, characterised by abnormal disease-associated prion protein (prp(d)) accumulations in the brain and lymphoreticular system (lrs). prior to neuroinvasion, tse agents often accumulate to high levels within the lrs, apparently without affecting immune function. however, our analysis of scrapie-affected sheep shows that prp(d) accumulations within the lrs are associated with mo ... | 2009 | 19997557 |
| prion-like doppel gene polymorphisms and scrapie susceptibility in portuguese sheep breeds. | the establishment of an association between prion protein gene (prnp) polymorphisms and scrapie susceptibility in sheep has enabled the development of breeding programmes to increase scrapie resistance in the european union. intense selection for prnp genotype may lead to correlated selection for genes linked to prnp. we intended to investigate if any association exists between genetic variation in prion-like protein doppel gene (prnd) and scrapie susceptibility, determined through prnp genotypi ... | 2010 | 19968641 |
| implications of conflicting associations of the prion protein (prp) gene with scrapie susceptibility and fitness on the persistence of scrapie. | existing mathematical models for scrapie dynamics in sheep populations assume that the prp gene is only associated with scrapie susceptibility and with no other fitness related traits. this assumption contrasts recent findings of prp gene associations with post-natal lamb survival in scrapie free scottish blackface populations. lambs with scrapie resistant genotypes were found to have significantly lower survival rates than those with susceptible genotypes. the present study aimed to investigate ... | 2009 | 19956715 |
| in vitro amplification of prions from milk in the detection of subclinical infections. | prions can be amplified by serial protein misfolding cyclic amplification (spmca) from the milk of a high proportion of apparently healthy, scrapie exposed sheep with prnp genotypes not previously associated with high disease penetrance. these data strongly suggest the widespread presence of subclinical scrapie infections within scrapie-exposed flocks containing sheep with a range of susceptible prnp genotypes. these data also lead to the hypothesis that similar subclinical disease states may be ... | 2009 | 19949303 |
| evidence for maternal transmission of scrapie in naturally affected flocks. | it has been known for many years that the offspring of scrapie affected ewes are at increased risk of developing scrapie but whether this is simply the result of an increased genetic susceptibility or transmission of infection has always been unclear. to contribute to clarify this we analysed the data collected in a detailed study of scrapie occurrence in a number of naturally affected commercial sheep flocks in great britain (gb) to investigate the association between prp genotype and parental ... | 2010 | 19945758 |
| prion protein self-peptides modulate prion interactions and conversion. | molecular mechanisms underlying prion agent replication, converting host-encoded cellular prion protein (prp(c)) into the scrapie associated isoform (prp(sc)), are poorly understood. selective self-interaction between prp molecules forms a basis underlying the observed differences of the prp(c) into prp(sc) conversion process (agent replication). the importance of previously peptide-scanning mapped ovine prp self-interaction domains on this conversion was investigated by studying the ability of ... | 2009 | 19943977 |
| glypican-1 mediates both prion protein lipid raft association and disease isoform formation. | in prion diseases, the cellular form of the prion protein, prp(c), undergoes a conformational conversion to the infectious isoform, prp(sc). prp(c) associates with lipid rafts through its glycosyl-phosphatidylinositol (gpi) anchor and a region in its n-terminal domain which also binds to heparan sulfate proteoglycans (hspgs). we show that heparin displaces prp(c) from rafts and promotes its endocytosis, suggesting that heparin competes with an endogenous raft-resident hspg for binding to prp(c). ... | 2009 | 19936054 |
| role of gfap in morphological retention and distribution of reactive astrocytes induced by scrapie encephalopathy in mice. | we have previously demonstrated that mutant mice bearing astrocytes deficient in glial fibrillary acidic protein (gfap) exhibited typical spongiform degeneration and prion plaque deposition. however, it remains to be determined whether there are astrocyte-specific alterations in the reactive response of astrocytes. herein, we analyzed morphological features of gfap(-)(/)(-) reactive astrocytes. light microscopic morphometry of mutant reactive astrocytes revealed reduced outlined cell area and sh ... | 2010 | 19931516 |
| [from the scrapie syndrome of sheep and goat to the mad cow disease - the history of the discovery of prion]. | since the discovery of scrapie syndrome in sheep and goats in 1730, there emerged a series of diseases such as creutzfeldt-jakob disease, kuru disease and mad cow disease etc. in the research of kuru disease, the american scientist d. carlteton gajdusek found a new virus without the characteristic of dna and rna, which was awarded the nobel prize in physiology in 1976. since then another american scientist, stanley b. prusiner, found a new virus-prion, taking protein as the genetic medium, which ... | 2009 | 19930927 |
| invited review: current state of genetic improvement in dairy sheep. | dairy sheep have been farmed traditionally in the mediterranean basin in southern europe, central europe, eastern europe, and in near east countries. currently, dairy sheep farming systems vary from extensive to intensive according to the economic relevance of the production chain and the specific environment and breed. modern breeding programs were conceived in the 1960s. the most efficient selection scheme for local dairy sheep breeds is based on pyramidal management of the population with the ... | 2009 | 19923587 |
| prion protein adsorption to soil in a competitive matrix is slow and reduced. | it is likely that the soil environment serves as a stable reservoir of infectious cwd and scrapie prions as well as a potential reservoir of bse. prion adsorption to soil could play an important role in prion mobility, proteolysis, and infectivity. we modified previously published methods to quantify adsorbed prions via direct detection and studied prion adsorption to soil and soil minerals as a function of time through 60 days. prion-infected brain homogenate was used as a complex, relevant pri ... | 2009 | 19921886 |
| identification of polymorphisms in the ovine shadow of prion protein (sprn) gene and assessment of their effect on promoter activity and susceptibility for classical scrapie. | shadow of prion protein (sprn) is an interesting candidate gene thought to be involved in prion pathogenesis. in humans, an association has already been discovered between mutations in sprn and the incidence of variant and sporadic creutzfeldt-jakob disease. however, in sheep, the effect of mutations in sprn is largely unknown. therefore, we analysed the presence of mutations in the entire ovine sprn gene, their association with scrapie susceptibility and their effect on sprn promoter activity. ... | 2010 | 19917049 |
| atypical scrapie: impact on eradication policies. | 2010 | 19910225 | |
| a retrospective immunohistochemical study reveals atypical scrapie has existed in the united kingdom since at least 1987. | atypical scrapie is a relatively recent discovery, and it was unknown whether it was a new phenomenon or whether it had existed undetected in the united kingdom national flock. before 1998, the routine statutory diagnosis of transmissible spongiform encephalopathy (tse) in sheep relied on the presence of tse vacuolation in the brainstem. this method would not have been effective for the detection of atypical scrapie. currently, immunohistochemistry (ihc) and western blot are commonly used for th ... | 2009 | 19901283 |
| prediction of prion protein genotype and association of this genotype with lamb performance traits of suffolk sheep. | the association of the prion protein (prp) gene with susceptibility to scrapie has formed the basis of selection programs aimed at eradicating the disease from sheep populations. animals are genotyped for the prp gene and those with the less susceptible genotypes are selected. the objectives of this study were to determine the effectiveness of predicting prp genotypes by using information from relatives and to investigate the association of the prp genotype with lamb performance traits in suffol ... | 2010 | 19897640 |
| doppel and prpc co-immunoprecipitate in detergent-resistant membrane domains of epithelial frt cells. | dpl (doppel) is a paralogue of the prpc (cellular prion protein), whose misfolded conformer (the scrapie prion protein, prpsc) is responsible for the onset of tses (transmissible spongiform encephalopathies) or prion diseases. it has been shown that the ectopic expression of dpl in the brains of some lines of prp-knockout mice provokes cerebellar ataxia, which can be rescued by the reintroduction of the prp gene, suggesting a functional interaction between the two proteins. it is, however, still ... | 2009 | 19888917 |
| alpha-synuclein deficiency in the c57bl/6jolahsd strain does not modify disease progression in the me7-model of prion disease. | we previously detailed how intrahippocampal inoculation of c57bl/6j mice with murine modified scrapie (me7) leads to chronic neurodegeneration (cunningham c, deacon r, wells h, boche d, waters s, diniz cp, scott h, rawlins jn, perry vh (2003) eur j neurosci 17:2147-2155.). our characterization of the me7-model is based on inoculation of this murine modified scrapie agent into c57bl/6j mice from harlan laboratories. this agent in the c57bl/6j host generates a disease that spans a 24-week time cou ... | 2010 | 19879926 |
| isolation of two distinct prion strains from a scrapie-affected sheep. | we performed a transmission study using mice to clarify the characteristics of the most recent case of scrapie in japan. the mice that were inoculated with the brain homogenate from a scrapie-affected sheep developed progressive neurological disease, and one of the scrapie-affected mice showed unique clinical signs during primary transmission. this mouse developed obesity, polydipsia, and polyuria. in contrast, the other affected mice exhibited weight loss and hypokinesia. in subsequent passages ... | 2009 | 19876594 |
| viral obesity: fact or fiction? | the aetiology of obesity is multifactorial. an understanding of the contributions of various causal factors is essential for the proper management of obesity. although it is primarily thought of as a condition brought on by lifestyle choices, recent evidence shows there is a link between obesity and viral infections. numerous animal models have documented an increased body weight and a number of physiologic changes, including increased insulin sensitivity, increased glucose uptake and decreased ... | 2010 | 19874530 |
| mouse vaccination with dendritic cells loaded with prion protein peptides overcomes tolerance and delays scrapie. | prion diseases are presumed to be caused by the accumulation in the brain of a pathological protein called prion protein (prp) scrapie which results from the transconformation of cellular prp, a ubiquitous glycoprotein expressed in all mammals. since all isoforms of prp are perceived as self by the host immune system, a major problem in designing efficient immunoprophylaxis or immunotherapy is to overcome tolerance. the present study was aimed at investigating whether bone-marrow-derived dendrit ... | 2010 | 19864503 |
| fast, broad-range disinfection of bacteria, fungi, viruses and prions. | effective disinfectants are of key importance for the safe handling and reprocessing of surgical instruments. this study tested whether new formulations containing sds, naoh and 1-propanol (n-propanol) are simultaneously active against a broad range of pathogens including bacteria, fungi, non-enveloped viruses and prions. inactivation and disinfection were examined in suspension and on carriers, using coagulated blood or brain homogenate as an organic contaminant. coomassie blue staining was use ... | 2010 | 19864502 |
| a rapid method for detection of prp by surface plasmon resonance (spr). | surface plasmon resonance was used to develop a rapid, label-free and sensitive immunoassay for detection of prion protein (prp). anti-prp monoclonal antibodies immobilized on the biosensor surface were allowed to bind various concentrations of cellular prion protein (prp(c)), followed by a pulse with additional soluble anti-prp polyclonal antibodies to intensify the signal. the interaction of antibody with antigen was monitored in real time. with this method, it was possible to detect prp(c) wi ... | 2009 | 19862471 |
| removal of tse agents by depth or membrane filtration from plasma products. | the removal of the abnormal form of prion protein i.e. prp(sc) by filtration steps in the plasma fractionation process has been investigated by immuno-western blotting. depth filtration has been shown to be capable of removing scrapie by 2-3 log from certain plasma product intermediates. these include cryoprecipitate supernatant, used for the manufacture of immunoglobulin and albumin, and albumin fraction v, by filtration using pall seitz or 3m cuno depth filters respectively. however no signifi ... | 2010 | 19854662 |
| the role of glycophosphatidylinositol anchor in the amplification of the scrapie isoform of prion protein in vitro. | transmissible spongiform encephalopathies are associated with an autocatalytic conversion of normal prion protein, prp(c), to a protease-resistant form, prpres. this autocatalytic reaction can be reproduced in vitro using a procedure called protein misfolding cyclic amplification (pmca). here we show that, unlike brain-derived prp(c), bacterially-expressed recombinant prion protein (rprp) is a poor substrate for prpres amplification in a standard pmca reaction. the differences between prp(c) and ... | 2009 | 19854187 |
| similarities between forms of sheep scrapie and creutzfeldt-jakob disease are encoded by distinct prion types. | transmissible spongiform encephalopathies such as scrapie in sheep, creutzfeldt-jakob disease (cjd) in humans, and bovine sporadic encephalopathy in cattle are characterized by the accumulation of a misfolded protein: the pathological prion protein. ever since bovine sporadic encephalopathy was discovered as the likely cause of the new variant of cjd in humans, parallels between human and animal transmissible spongiform encephalopathies must be viewed under the aspect of a disease risk for human ... | 2009 | 19850886 |
| adoptive transfer of t lymphocytes sensitized against the prion protein attenuates prion invasion in scrapie-infected mice. | there is to date no effective way of preventing or curing neurodegenerative diseases such as alzheimer disease or transmissible spongiform encephalopathies. the idea of treating those conditions by immunological approaches has progressively emerged over the last ten years. encouraging results have been reported in alzheimer disease and in peripheral forms of mouse prion diseases following passive injection of abs or active immunization against the peptides or proteins presumably at the origin of ... | 2009 | 19846876 |
| manganese enhances prion protein survival in model soils and increases prion infectivity to cells. | prion diseases are considered to be transmissible. the existence of sporadic forms of prion diseases such as scrapie implies an environmental source for the infectious agent. this would suggest that under certain conditions the prion protein, the accepted agent of transmission, can survive in the environment. we have developed a novel technique to extract the prion protein from soil matrices. previous studies have suggested that environmental manganese is a possible risk factor for prion disease ... | 2009 | 19844576 |
| design, synthesis, and structure-activity relationship of indole-3-glyoxylamide libraries possessing highly potent activity in a cell line model of prion disease. | transmissible spongiform encephalopathies (tses) are a family of invariably fatal neurodegenerative disorders for which no effective curative therapy currently exists. we report here the synthesis of a library of indole-3-glyoxylamides and their evaluation as potential antiprion agents. a number of compounds demonstrated submicromolar activity in a cell line model of prion disease together with a defined structure-activity relationship, permitting the design of more potent compounds that effecte ... | 2009 | 19842664 |
| polymorphisms in the hsp90aa1 5' flanking region are associated with scrapie incubation period in sheep. | susceptibility to scrapie is mainly controlled by point mutations at the prnp locus. however, additional quantitative trait loci (qtl) have been identified across the genome including a region in oar18. the gene which encodes the inducible form of the cytoplasmic hsp90 chaperone (hsp90aa1) maps within this region and seems to be associated with the resistance/susceptibility to scrapie in sheep. here, we have analyzed several polymorphisms which were previously described in the ovine hsp90aa1 5' ... | 2010 | 19838832 |
| prion protein detection in serum using micromechanical resonator arrays. | prion proteins that have transformed from their normal cellular counterparts (prp(c)) into infectious form (prp(res)) are responsible for causing progressive neurodegenerative diseases in numerous species, such as bovine spongiform encephalopathy (bse) in cattle (also known as mad cow disease), scrapie in sheep, and creutzfeldt-jakob disease (cjd) in humans. due to a possible link between bse and cjd it is highly desirable to develop non-invasive and ante mortem tests for the detection of prion ... | 2009 | 19836525 |
| mapping of quantitative trait loci affecting classical scrapie incubation time in a population comprising several generations of scrapie-infected sheep. | although susceptibility to scrapie is largely controlled by the prp gene, the role of other genes that affect scrapie resistance in sheep is now confirmed. following the detection of quantitative trait loci (qtl) on chromosomes 6 and 18 in a half-sib family with an arq/vrq susceptible prp genotype, the whole pedigree of a naturally infected flock was investigated to confirm these qtl regions in different prp genotypes. the present study has allowed us to confirm the qtl on chromosome 18, and to ... | 2010 | 19828762 |
| strain-specific proteolytic processing of the prion protein in prion diseases of ruminants transmitted in ovine transgenic mice. | the cerebral prion protein (prp) isolated in the absence of proteinase k digestion, from ruminants prion sources transmitted to ovine transgenic mice, was studied by western blot analysis. a c2 prp fragment, showing strain-specific cleavages, similar to those observed after proteinase k or thermolysin digestion, accumulated in the brain. 'ch1641-like' scrapie was characterized by the unique accumulation of a more c-terminally cleaved prp fragment (ctf14). a similar, protease-resistant, prp produ ... | 2010 | 19828761 |
| the evaluation of exposure risks for natural transmission of scrapie within an infected flock. | although the epidemiology of scrapie has been broadly understood for many years, attempts to introduce voluntary or compulsory controls to eradicate the disease have frequently failed. lack of precision in defining the risk factors on farm has been one of the challenges to designing control strategies. this study attempted to define which parts of the annual flock management cycle represented the greatest risk of infection to naive lambs exposed to the farm environment at different times. | 2009 | 19818127 |
| conformational diseases: looking into the eyes. | conformational diseases, a general term comprising more than 40 disorders are caused by the accumulation of unfolded or misfolded proteins. improper protein folding (misfolding) as well as accrual of unfolded proteins can lead to the formation of disordered (amorphous) or ordered (amyloid fibril) aggregates. the gradual accumulation of protein aggregates and the acceleration of their formation by stress explain the characteristic late or episodic onset of the diseases. the best studied in this g ... | 2010 | 19808079 |
| transmissibility of atypical scrapie in ovine transgenic mice: major effects of host prion protein expression and donor prion genotype. | atypical scrapie or nor98 has been identified as a transmissible spongiform encephalopathy (tse) that is clearly distinguishable from classical scrapie and bse, notably regarding the biochemical features of the protease-resistant prion protein prp(res) and the genetic factors involved in susceptibility to the disease. in this study we transmitted the disease from a series of 12 french atypical scrapie isolates in a transgenic mouse model (tgovprp4) overexpressing in the brain approximately 0.25, ... | 2009 | 19806224 |
| changes in sympathetic activity in prion neuroinvasion. | prion diseases are neurodegenerative diseases affecting humans and animals in which the infectious agent or prion is prp(res), a protease-resistant conformer of the cell protein prp. the natural transmission route of prion diseases is peripheral infection, with the lymphoreticular system (lrs) and peripheral nerves being involved in animal models of scrapie neuroinvasion and human prion diseases. to study the effects of prp neuroinvasion on sympathetic nerve function, we measured plasma catechol ... | 2010 | 19804827 |
| redox control of prion and disease pathogenesis. | imbalance of brain metal homeostasis and associated oxidative stress by redox-active metals like iron and copper is an important trigger of neurotoxicity in several neurodegenerative conditions, including prion disorders. whereas some reports attribute this to end-stage disease, others provide evidence for specific mechanisms leading to brain metal dyshomeostasis during disease progression. in prion disorders, imbalance of brain-iron homeostasis is observed before end-stage disease and worsens w ... | 2010 | 19803746 |
| visual pathology in animal prion diseases. | prion diseases, also known as the transmissible spongiform encephalopathies (tses), are a group of slowly developing neurodegenerations occurring in human and animals. prion diseases can be transferred between animals, humans, from humans to animals, and from animals to humans. as a result, the central nervous system is attacked, resulting in microglia activation, astrocytosis, prion plaque deposition, and neuronal degeneration. prion also targets on the eye and brain visual system. in scrapie-i ... | 2009 | 19795355 |
| the role of the prion protein membrane anchor in prion infection. | normal cellular and abnormal disease-associated forms of prion protein (prp) contain a c-terminal glycophosphatidyl-inositol (gpi) membrane anchor. the importance of the gpi membrane anchor in prion diseases is unclear but there are data to suggest that it both is and is not required for abnormal prion protein formation and prion infection. utilizing an in vitro model of prion infection we have recently demonstrated that, while the gpi anchor is not essential for the formation of abnormal prion ... | 2009 | 19786843 |
| the effects of host age on follicular dendritic cell status dramatically impair scrapie agent neuroinvasion in aged mice. | following peripheral exposure, many transmissible spongiform encephalopathy (tse) agents accumulate first in lymphoid tissues before spreading to the cns (termed neuroinvasion) where they cause neurodegeneration. early tse agent accumulation upon follicular dendritic cells (fdcs) in lymphoid follicles appears critical for efficient neuroinvasion. most clinical cases of variant creutzfeldt-jakob disease have occurred in young adults, although the reasons behind this apparent age-related susceptib ... | 2009 | 19786551 |