| scrapie prion liposomes and rods exhibit target sizes of 55,000 da. | scrapie is a degenerative neurologic disease in sheep and goats which can be experimentally transmitted to laboratory rodents. considerable evidence suggests that the scrapie agent is composed largely, if not entirely, of an abnormal isoform of the prion protein (prpsc). inactivation of scrapie prions by ionizing radiation exhibited single-hit kinetics and gave a target size of 55,000 +/- 9000 mol wt. the inactivation profile was independent of the form of the prion. scrapie agent infectivity in ... | 1988 | 3130718 |
| in vitro expression of cloned prp cdna derived from scrapie-infected mouse brain: lack of transmission of scrapie infectivity. | a cdna for the prion protein (prp) derived from scrapie-infected mouse brain was expressed in c127 mouse cells in vitro under the control of the mouse metallothionein promoter. prp synthesis was detected by immunoprecipitation using a rabbit antibody specific for a 15 amino acid prp peptide. homogenates of cells expressing the cloned prp cdna inoculated into weanling mice failed to induce clinical scrapie during 190 days of observation. we conclude that either prp is not the transmissible agent ... | 1988 | 3137000 |
| search for a scrapie-specific nucleic acid: a progress report. | scrapie agent contains a proteinaceous component as well as an 'informational' molecule (suggested by the existence of distinct strains of scrapie). these operationally defined entities may be the same molecule, an infectious protein, or distinct, in which case a nucleic acid might encode the genetic information. purification of scrapie agent enriched a protein, prpsc, by virtue of its relative protease resistance. there is only a single prp gene and the primary translation product of prp mrna i ... | 1988 | 3137001 |
| pathogenesis of experimental scrapie. | most of our understanding of the pathogenesis of the unconventional slow infections comes from studies of experimental scrapie in mice and hamsters. after injection by non-neural peripheral routes, pathogenesis necessarily involves the lymphoreticular system (lrs) before the central nervous system (cns). available evidence indicates haematogenous spread from the site of injection to the scrapie replication sites in the lrs; later, infection spreads along visceral autonomic nerves from the lrs to ... | 1988 | 3137002 |
| a modified host protein model of scrapie. | the scrapie agent is still not completely characterized biochemically and ultrastructurally, but its requirement for a functional protein has been established. purification of the scrapie agent by methods using digestion with proteinase k yields a glycoprotein with an apparent mass of 27-30 kda (prp 27-30). in contrast, a 33-37 kda glycoprotein, called sp33-37, is the major protein component isolated from scrapie-affected brain when protease digestion is not used. sp33-37 is the product of a nor ... | 1988 | 3136999 |
| [relation between slow virus infection of animals and man, their pathogenicity and resistance to therapy]. | besides conventional slow viruses, a category of pathogens exist, called "unconventional slow viruses". the latter evoke laughing death syndrome, creutzfeldt-jakob disease (resp. its special form of gerstmann-sträussler's syndrome) in man, in animal scrapie, infectious encephalopathy of the mink, and chronic wasting disease. they all are relatives, and their characteristics are longtime incubation, lacking immune reactions, high chemical and physical resistance, no proof of nucleic acids till no ... | 1988 | 3136063 |
| a chronological study of experimental scrapie in mice. | the development of scrapie-associated particles and lesions in four regions of the brain was studied in mice over a period of 30 weeks. characteristic tubulovesicular particles, identical to those previously described, were first found about half way through the incubation period in mice inoculated by four different routes. the particles are found in brains with scrapie and other spongiform encephalopathies; they have never been seen in other conditions, and potentially represent the infectious ... | 1988 | 3131975 |
| the unusual properties of ch1641, a sheep-passaged isolate of scrapie. | an isolate of scrapie designated ch1641 was identified from a natural case of scrapie in a cheviot sheep by passage in sheep and goats. it has not been possible to transmit scrapie to mice from this source. the sip gene which controls the incubation periods of experimental scrapie in cheviot sheep has two alleles; sa which shortens and pa which lengthens the incubation periods of most strains of scrapie after the first experimental injection in sheep (the a group of strains). the ch1641 isolate ... | 1988 | 3140468 |
| superovulation and embryo transfer. | | 1988 | 3140469 |
| adrenal involvement in scrapie-induced obesity. | in previous studies we found an increase in body weight during the preclinical phase of disease in certain scrapie strain-mouse strain combinations. the effect was augmented by injection into the hypothalamus. in the present study, we found an increase in food consumption (compared to the normal mouse brain injection group) for both the 139a and me7 scrapie groups, although only the me7 group showed an increase in body weight. in a scrapie strain-mouse strain combination that showed an increase ... | 1988 | 3141932 |
| effects of the antiserum against a fraction enriched in scrapie-associated fibrils on the scrapie incubation period in mice. | an antiserum against a fraction enriched for scrapie-associated fibrils (saf), was examined for its effects on scrapie incubation period by inoculating mice either intraperitoneally or intracerebrally with various dilutions of the serum mixed with scrapie-infected mouse brain homogenate. after intraperitoneal inoculation the mean time of the incubation period increased with increasing concentrations of the antiserum in a statistically significant fashion, when the serum dilutions were made with ... | 1988 | 3143050 |
| [cytomorphologic study of a line of hybrid somatic cells persistently infected with the scrapie agent]. | virological, cytological and electron microscopic methods were used to study the peculiarities of the scrapie agent persistence in the tissue culture of the mouse and human hybrid cells. a long-term persistence of the scrapie agents in the cells (658 days) has been obtained. the fact of persistence is confirmed by the results of biotest and electron microscopic studies of the mouse cns. the agent persistence promotes a decrease in the mitotic activity of the infected cells and development of the ... | 1988 | 3143174 |
| transmissible and non-transmissible amyloidoses: autocatalytic post-translational conversion of host precursor proteins to beta-pleated sheet configurations. | | 1988 | 3143742 |
| incubation periods in six models of intraperitoneally injected scrapie depend mainly on the dynamics of agent replication within the nervous system and not the lymphoreticular system. | the pathogenesis of intraperitoneally injected me7 scrapie has been studied in two sinc genotypes of mice which gave predictable but widely different incubation periods. comparisons were made with three other mouse scrapie models and one model in hamsters (involving different strains of agent and an untyped isolate from sheep). average incubation periods ranged from 114 days in the fastest model (263k/hamsters) to 482 days in the slowest (me7/sincp7 mice). there were only small differences betwe ... | 1988 | 3143808 |
| the senile dementias: a new model. | kuru and creutzfeldt jakob disease are fatal neurological disorders in humans that are transmissible to humans and other experimental animals. largely because of their transmissibility the etiology of these diseases has been ascribed to infectious agents classified as "slow" or unconventional viruses. a related neurological disease in sheep called scrapie has also been ascribed to infection by slow viruses. despite more than 20 years of intensive research no viruses or other infectious agents ha ... | 1988 | 3144644 |
| pathogenesis of scrapie is faster when infection is intraspinal instead of intracerebral. | previous studies of mice infected peripherally with 139a scrapie showed that scrapie agent initially replicates outside the cns and that invasion of the cns occurs several weeks later by neural spread of infection along visceral autonomic fibres to the mid-thoracic cord, and thence to brain. direct intracerebral infection of brain bypasses the need for extraneural replication and gives shorter incubation periods than peripheral routes. however, it was also found that the duration of the scrapie ... | 1987 | 3148813 |
| genetics and polymorphism of the mouse prion gene complex: control of scrapie incubation time. | the mouse prion protein (prp) gene (prn-p), which encodes the only macromolecule that has been identified in scrapie prions, is tightly linked or identical to a gene (prn-i) that controls the duration of the scrapie incubation period in mice. constellations of restriction fragment length polymorphisms distinguish haplotypes a to f of prn-p. the prn-pb allele encodes a prp that differs in sequence from those encoded by the other haplotypes and, in inbred mouse strains, correlates with long scrapi ... | 1988 | 3149717 |
| cona induced suppressor cells in scrapie-infected mice. | lymphocyte suspensions prepared from the spleens of mice (lacg/com) clinically affected with scrapie (me7) were cultured for 48 hrs in the presence of concanavalin (cona) in order to induce suppressor cells. these cells behaved exactly as similarly prepared cells from normal age-matched mice in suppressing the response of fresh normal splenic lymphocytes to phytohaemagglutinin (pha). | 1985 | 3156445 |
| amyloid plaque core protein in alzheimer disease and down syndrome. | we have purified and characterized the cerebral amyloid protein that forms the plaque core in alzheimer disease and in aged individuals with down syndrome. the protein consists of multimeric aggregates of a polypeptide of about 40 residues (4 kda). the amino acid composition, molecular mass, and nh2-terminal sequence of this amyloid protein are almost identical to those described for the amyloid deposited in the congophilic angiopathy of alzheimer disease and down syndrome, but the plaque core p ... | 1985 | 3159021 |
| breeding controls rein in scrapie in yorkshire. | | 1988 | 3176270 |
| cerebrovascular amyloid in scrapie-affected sheep reacts with antibodies to prion protein. | in an immunohistochemical study of naturally-occurring and experimental scrapie in sheep, deposits of cerebrovascular amyloid were found to react with antibodies to hamster scrapie prion protein (prp 27-30), but not with antibodies to the amyloid beta-protein of alzheimer's disease. it is concluded that this vascular amyloid is formed from prp and is therefore closely associated with scrapie infection. it is likely that this amyloid is formed from a host precursor protein as a specific pathologi ... | 1988 | 3185993 |
| scrapie in sheep in central and southern italy. | seven cases of scrapie were encountered in six flocks of local breeds of sheep in central and southern italy. scrapie has never been reported in these areas, in which the great majority of the italian sheep population is concentrated. the diagnosis was based on clinical and histopathological findings. | 1988 | 3188385 |
| comparison of spongiform lesions in experimental scrapie and rabies in skunks. | striped skunks were inoculated intracerebrally with the scrapie agent (suspension of brain from a naturally infected suffolk sheep) or intramuscularly with street rabies virus (suspension of salivary glands from naturally infected skunks). those given the scrapie agent developed clinical signs of weakness, posterior ataxia, and emaciation after incubated periods of 8 to 23 months. those inoculated with rabies virus developed clinical signs of rabies (aggressive behavior, hyperexcitability, ataxi ... | 1988 | 3213430 |
| abomasal dilatation and emptying defect in a flock of suffolk ewes. | abomasal dilatation and emptying defect was identified in 14 of 130 suffolk sheep from a single flock in northern california. abomasal dilatation and emptying defect was diagnosed in 13 of the sheep between november 1986 and april 1987. all affected sheep were ewes and in all, the condition developed during the lambing season. clinical signs consisted of chronic anorexia and weight loss. laboratory data from affected ewes reflected concurrent disease and was not helpful in diagnosis of the disea ... | 1988 | 3215813 |
| bovine spongiform encephalopathy: epidemiological studies. | this study, initiated in june 1987, describes the epidemiology of bovine spongiform encephalopathy (bse), a recently described novel neurological disease of domestic cattle first identified in great britain in november 1986. records suggested that the earliest suspected cases occurred in april 1985. there was variability in the presenting signs and the disease course, but the majority of cases developed behavioural disorders, gait ataxia, paresis and loss of bodyweight; pruritus was not a predom ... | 1988 | 3218047 |
| immunostaining of scrapie cerebral amyloid plaques with antisera raised to scrapie-associated fibrils (saf). | brain sections from 16 different mouse scrapie models were immunostained with antisera to scrapie-associated fibrils (saf) from three experimental scrapie sources (hamster 263k, mouse me7 and mouse 22l). these models involved seven strains of scrapie injected intracerebrally or intraperitoneally into a range of inbred mouse strains, producing a wide variety of neuropathological changes. the only brain structures which were positively immunostained were amyloid plaque cores in those models in whi ... | 1988 | 3221978 |
| the occurrence of cytoplasmic lamellar bodies in scrapie-infected and normal hamster brains. | | 1988 | 3226555 |
| prions. | | 1988 | 3251470 |
| scrapie in sheep in sweden. | | 1988 | 3256247 |
| tubulovesicular structures in experimental creutzfeldt-jakob disease and scrapie. | tubulovesicular structures, measuring 20-50 nm in diameter, were found in dilated neuronal processes in brains from mice infected with the fujisaki strain of creutzfeldt-jakob disease virus. these particles were similar to those observed in brains from hamsters infected with scrapie. these structures are consistently present in naturally occurring and experimentally induced spongiform encephalopathies, irrespective of the host species or virus strain. their role in pathogenesis is undetermined. | 1988 | 3137185 |
| scrapie-infected murine neuroblastoma cells produce protease-resistant prion proteins. | scrapie and creutzfeldt-jakob disease are transmissible, degenerative neurological diseases caused by prions. considerable evidence argues that prions contain protease-resistant sialoglycoproteins, designated prpsc, encoded by a cellular gene. the prion protein (prp) gene also encodes a normal cellular protein designated prpc. we established clonal cell lines which support the replication of mouse scrapie or creutzfeldt-jakob disease prions. mouse neuroblastoma n2a cells were exposed to mouse sc ... | 1988 | 3282080 |
| the epidemiology of creutzfeldt-jakob disease: conclusion of a 15-year investigation in france and review of the world literature. | during the 15-year period 1968-1982, a total of 329 patients dying of creutzfeldt-jakob disease (cjd) were identified in continental france. annual mortality rates stabilized at 0.5 to 0.6 cases per million (1.1 to 1.2 cases per million in paris). six percent of cases were familial. although the frequency of cjd was related to population density, no contacts could be established among the great majority of patients. no association with socioeconomic factors, preceding trauma or surgery (exceptin ... | 1987 | 3295589 |
| [transmissible spongiform encephalopathy. natural diseases and experimental studies]. | | 1986 | 3295591 |
| pituitary growth hormone and creutzfeldt-jakob disease. | | 1986 | 3296633 |
| immunoblotting of creutzfeldt-jakob disease prion proteins: host species-specific epitopes. | creutzfeldt-jakob disease (cjd) is a rare dementia that is generally found in older people and is caused by unusual infectious pathogens or prions. using rabbit antisera raised against hamster scrapie prion proteins (haprpsc), we identified by immunoblotting human cjd prion proteins (huprpcjd) in the brains of 14 patients dying of cjd. extracts from 6 of the patients were transmitted to mice after prolonged incubation. the rabbit antisera raised against haprpsc also reacted with the mouse cjd pr ... | 1987 | 3300520 |
| [creutzfeldt-jakob disease: report of a case]. | a case of creutzfeldt-jakob disease (cjd) in a 76 year-old man is presented. the clinical picture included a rapid progressive dementia associated with ataxia, global aphasia, myoclonus and pyramidal signs; death occurred after about 4 months. there was an antecedent of chemical trauma caused by plant liquid on right eye 12 to 18 months before. the electroencephalogram showed diffuse slow activity and the neuropathological findings were typical. the detection of a protein called "prion" or prp27 ... | 1987 | 3300614 |
| iatrogenic creutzfeldt-jakob disease. | over the past 2 years, creutzfeldt-jakob disease (cjd) has affected several patients who received cadaver pituitary-derived growth hormone (pit-hgh) and one patient who received a cadaveric dura mater graft. the risk of iatrogenic transmission of cjd has long been recognized, but until recently, the low prevalence of the disorder and minimal use of therapeutic products derived from human tissues may have limited the risk. from 1963 to 1985, approximately 10,000 children received pit-hgh. these p ... | 1987 | 3306455 |
| immunoaffinity purification and neutralization of scrapie prion infectivity. | prions are unusual infectious pathogens causing scrapie of sheep and goats as well as creutzfeldt-jakob disease of humans. biochemical and genetic studies contend that the scrapie isoform of the prion protein (prpsc) is a major component of the prion. limited proteinase k digestion of prpsc produced a protein of 27-30 kda. after dispersion of brain microsomes isolated from scrapie-infected hamsters into detergent-lipid-protein complexes, copurification of prpsc and scrapie infectivity was obtain ... | 1988 | 3137571 |
| purification and properties of the cellular and scrapie hamster prion proteins. | during scrapie infection an abnormal isoform of the prion protein (prp), designated prpsc, accumulates and is found to copurify with infectivity; to date, no nucleic acid has been found which is scrapie-specific. both uninfected and scrapie-infected cells synthesize a prp isoform, denoted prpc, which exhibits physical properties that differentiate it from prpsc. prpc was purified by immunoaffinity chromatography using a prp-specific monoclonal antibody cross-linked to protein-a--avidgel. prpsc w ... | 1988 | 3138115 |
| can potential hazard of creutzfeldt-jakob disease infectivity be reduced in the production of human growth hormone? inactivation experiments with the 263k strain of scrapie. rapid communication. | scrapie infectivity is reduced 5-6 logs following filtration through 100,000 mw cut-off filter plus overnight treatment with 6 m urea. these steps, applied to purified human growth hormone (hgh), increase the margin of safety of hgh. | 1988 | 3277594 |
| tubulofilaments in negatively stained scrapie-infected brains: relationship to scrapie-associated fibrils. | a simple method was devised for negative-stain transmission electron microscopy of brain infected with the agent of scrapie. brains of infected hamsters contained large masses of tubulofilamentous structures with irregular fuzzy surfaces. brains of mice infected with creutzfeldt-jakob disease agent contained similar tubulofilaments in smaller numbers. the abnormal tubulofilaments resembled but were distinguished from normal microtubules. on grids soaked in sodium dodecyl sulfate the abnormal tub ... | 1987 | 3313402 |
| sheep major histocompatibility (ola) complex: linkage between a scrapie susceptibility/resistance locus and the ola complex in ile-de-france sheep progenies. | as seen on their family trees, ile-de-france sheep with scrapie show genetic susceptibility to this disease, which is transmitted via scrs, an autosomal recessive gene. scrapie occurred in homozygous recessive sheep, whereas the presence of the dominant resistance allele scrr sufficed to prevent this disease in heterozygous animals. this hypothesis, previously proposed by parry (1962), was tested in a study involving 133 crossings of sheep of different genotypes, and verified in the observed pro ... | 1988 | 3334722 |
| first report of ovine scrapie in cyprus. | | 1988 | 3345421 |
| the comparative immunoreactivities of brain amyloids in alzheimer's disease and scrapie. | an antibody was raised to a synthetic peptide corresponding to a published sequence for the first 24 residues of a cerebrovascular amyloid peptide (cvap). immunohistochemical staining of tissue sections revealed that the antibody bound extensively to cerebrovascular amyloid in alzheimer disease (ad/sdat) and down's syndrome cases. the antibody bound less extensively to neuritic plaques (primitive and mature) and indetectably to neurofibrillary tangles. the antibody did not label scrapie plaques, ... | 1987 | 3318271 |
| molecular and genetic aspects of the pathogenesis of viral infections of the central nervous system. | viral pathogenesis can be defined in terms of a series of successive interactions between a virus and its target host. in order for a virus to injure a target organ such as the central nervous system (cns), it must first enter the host animal, replicate in some primary site near its place of entry, spread from this site to the cns and infect and injure specific populations of cells within the cns. at each of these steps, the virus must avoid or overcome a variety of immunological and nonimmunolo ... | 1987 | 3315238 |
| bovine spongiform encephalopathy: time to take scrapie seriously. | | 1988 | 3394240 |
| genetic control of scrapie in cheviot and suffolk sheep. | | 1988 | 3420785 |
| [slow viruses]. | | 1987 | 3321384 |
| effect of bacterial flora and mouse genotype (euthymic or athymic) on scrapie pathogenesis. | euthymic and athymic female balb/c mice, reared under either germfree or defined flora conditions, were used to investigate the pathogenesis of scrapie after intracerebral or intraperitoneal inoculation. time in days to onset of clinical signs (stage i), to endstage (stage ii), and the time interval between stage i and stage ii were compared among groups. in addition, scrapie agent titers in spleen were determined at 28 and 90 days after infection, as were agent titers in spleen and brain at sta ... | 1986 | 3464673 |
| transmission in nfs/n mice of the heritable spongiform encephalopathy associated with the gray tremor mutation. | it has been shown that the autosomal recessive mutation, gray tremor (gt) was associated in the homozygous state (gt/gt) with a rapidly fatal spongiform encephalopathy. heterozygotes (+/gt) developed mild asymptomatic spongiform brain lesions as did recipient inbred mice inoculated with gt/gt brain homogenates, some of whom also showed behavioral abnormalities [sidman, r. l., kinney, h. c. & sweet, h. o. (1985) proc. natl. acad. sci. usa 82, 253-257]. in these studies, inbred nfs/n mice inoculat ... | 1987 | 3473486 |
| the molecular pathogenesis of astrogliosis in scrapie and alzheimer's disease. | in slow infections caused by scrapie and other unconventional agents, and in alzheimer's disease (ad), the formation of neuritic plaques and the increase in astrocytes and astrocyte-specific protein, glial fibrillary acidic protein (gfap), are pathological changes common to both conditions. with the rationale that these parallels imply convergent pathogenetic mechanisms, we identified a gene whose expression increases in both. we now report the results of a more extensive analysis of this gene a ... | 1987 | 3507557 |
| diagnosis of creutzfeldt-jakob disease by western blot identification of marker protein in human brain tissue. | we tested purified preparations of brain tissue from 39 patients with creutzfeldt-jakob disease, gerstmann-sträussler-scheinker syndrome, or kuru, and from 32 patients with a variety of nonspongiform degenerative diseases, with the use of western blots against an antiserum to a similarly purified fraction made from scrapie-infected hamster brain. positive reactions occurred in 81 percent of the 31 specimens from the patients with creutzfeldt-jakob disease (and in all of the 7 specimens that were ... | 1986 | 3511385 |
| [prions--a new microbiological and neurological problem]. | | 1986 | 3520517 |
| isolation of a cdna clone encoding the leader peptide of prion protein and expression of the homologous gene in various tissues. | we have isolated a hamster cdna clone representing the coding sequences for the entire precursor of prion protein (prp) 27-30. this clone encodes a protein of 254 residues and contains an in-frame atg codon 42 bases upstream from the one previously reported. analysis of the predicted amino acid sequence suggests that the prp precursor protein contains an amino-terminal signal sequence, and a membrane-spanning domain in the carboxyl terminus. cleavage of the signal peptide would produce a mature ... | 1986 | 3529083 |
| familial creutzfeldt-jakob disease in france: epidemiological implications. | of 329 patients dying of creutzfeldt-jakob disease (cjd) in continental france between 1968 and 1982, 19 (6%) were familial cases. genealogical investigation permitted the identification of 19 additional cases, bringing the total number of familial cjd cases reported here to 38. there are 6 definitely affected families, yielding an average of 6.3 cases per family. mediterranean jews account for one-third of all the cases, with tunisian jews constituting two-thirds of this ethnic group. males and ... | 1986 | 3542553 |
| [autocatalytic nature of "slow virus infections"]. | a concept that considers the causative nature of the so-called "slow virus infections", causing syndromes of spongiform encephalopathies in man and animals as a chain autocatalytic process is put forward. according to this concept, prp(27-30) protein, isolated recently from the brains of scrapie-infected animals, is a c-terminal domain of the normal protein component of brain tissue which is a latent zimogen. certain clinical and experimental data are discussed within the framework of this conce ... | 1986 | 3543657 |
| incubation periods and survival times for mice injected stereotaxically with three scrapie strains in different brain regions. | incubation period and survival time were determined in c57bl mice which had been injected stereotaxically with either the 139a, me7 or 22l strain of scrapie in one of five different brain regions (cerebral cortex, caudate nucleus, thalamus, substantia nigra, cerebellum). the injection of 139a in the caudate nucleus, thalamus, substantia nigra or cerebellum resulted in significantly shorter incubation periods than following cerebral cortex injection. for me7, mice injected in the thalamus and cer ... | 1987 | 3546594 |
| biogenesis and transmembrane orientation of the cellular isoform of the scrapie prion protein [published errratum appears in mol cell biol 1987 may;7(5):2035]. | considerable evidence suggests that the scrapie prion protein (prp) is a component of the infectious particle. we studied the biogenesis and transmembrane orientation of an integral-membrane form of prp in a cell-free transcription-linked translation-coupled translocation system programmed with a full-length prp cdna cloned behind the sp6 promoter. translation of sp6 transcripts of the cdna or of native mrna from either normal or infected hamster brain in the absence of dog pancreas membranes re ... | 1987 | 3547085 |
| transmissible virus dementia: evaluation of a zoonotic hypothesis. | creutzfeldt-jakob disease (cjd) and kuru are subacute transmissible dementing encephalopathies characterized by spongiform changes in the brain. scrapie is a similar slow viral encephalopathy which affects sheep, goats and certain other animals. anecdotal reports suggest that creutzfeldt-jakob disease could be a zoonosis. to evaluate the possibility that cjd is acquired from animals, a case-control study was conducted on 26 well-documented cjd cases and 40 controls. data were collected on exposu ... | 1986 | 3550507 |
| [virion or prion? second thoughts on the physicochemical structure of the infective agent in scrapie]. | | 1986 | 3550513 |
| prions are novel infectious pathogens causing scrapie and creutzfeldt-jakob disease. | | 1986 | 3551942 |
| prion diseases and central nervous system degeneration. | | 1987 | 3552382 |
| neuronal cytoskeleton in aging and dementia. | | 1986 | 3554352 |
| on the biology of prions. | prions cause scrapie and creutzfeldt-jakob disease (cjd); these infectious pathogens are composed largely, if not entirely, of protein molecules. no prion-specific polynucleotide has been identified. purified preparations of scrapie prions contain high titers (greater than or equal to 10(9.5) id50/ml), one protein (prp 27-30) and amyloid rods (10-20 nm in diameter x 100-200 nm in length). considerable evidence indicates that prp 27-30 is required for and inseparable from scrapie infectivity. prp ... | 1987 | 3554880 |
| prions causing degenerative neurological diseases. | prions cause degenerative neurological diseases--scrapie in animals and creutzfeldt-jakob disease in humans. the novel properties and structure of the prion distinguish it from viruses. | 1987 | 3555303 |
| neuronal origin of cerebral amyloidogenic proteins: their role in alzheimer's disease and unconventional virus diseases of the nervous system. | the protein component of alzheimer's disease amyloid (neurofibrillary tangles, amyloid plaque cores and congophilic angiopathy) is an aggregated polypeptide with a subunit mass of approximately 4 kda (the a4 monomer). the aggregational properties of this monomer may explain the amyloidogenic nature of the protein: the native monomer forms dimers, tetramers and higher oligomeric species which are dependent on ph, ionic strength and concentration; the synthetic peptide corresponding to residues 1- ... | 1987 | 3556089 |
| evidence suggesting that prp is not the infectious agent in creutzfeldt-jakob disease. | it has been suggested that the infectious agents of scrapie and creutzfeldt-jakob disease (cjd) are 'prions' constituted by a protease resistant glycopeptide, prp. to analyze the role of prp in cjd infectivity we re-evaluated the biochemical characteristics of infectivity. first, when the infectious agent is not aggregated, infectivity is exquisitely sensitive to proteinase k treatment, and therefore a proteinase-k-resistant molecule (e.g. prp) is unlikely to contain information essential for ag ... | 1987 | 3556164 |
| electron microscopic observations on dystrophic neurites in hamster brains infected with the 263k strain of scrapie. | increased numbers of dystrophic neurites filled with inclusions were found in the brains of syrian hamsters inoculated with scrapie but not in control animals. these neurites were seen as single entities or as clusters of up to three. the possibility that these structures are the beginning of the formation of plaques is discussed. | 1987 | 3558903 |
| astrocytic reaction in experimental scrapie in hamsters. | severe glial reaction (gliocytosis) in hamsters infected with the 263k strain of scrapie is described. gliocytosis is an extremely rare phenomenon in scrapie-affected mice. in hamsters, however, it forms an important and stable feature of the neuropathology. both astrocytic hyperplasia and hypertrophy are described. the author discusses briefly the possible contribution of the scrapie agent and of the host use in the experiments described here to the development of glial changes. | 1987 | 3558905 |
| abnormal tubulovesicular particles in brains of hamsters with scrapie. | abnormal tubulovesicular particles of an average diameter of 23 nm have been observed in brains of mice with scrapie as well as in other animals with spongiform encephalopathies, but they were thought to be absent from the brains of hamsters with scrapie in which the highest known concentrations of the infectious agent occur. we observed in neuronal processes of hamsters as well as mice clusters of those tubulovesicular structures, most often in postsynaptic terminals. such particles have now be ... | 1987 | 3562457 |
| ovine abomasal enlargement and scrapie. | | 1987 | 3576941 |
| detection of scrapie-associated fibrils as an aid to the diagnosis of natural sheep scrapie. | | 1987 | 3590556 |
| scrapie-induced obesity in mice. | | 1987 | 3598239 |
| scrapie infection diminishes spines and increases varicosities of dendrites in hamsters: a quantitative golgi analysis. | an altered morphology of neuronal dendrites has been shown to be associated with many degenerative diseases of the central nervous system (cns). scrapie is a cns degenerative disorder caused by a novel infectious particle or prion. golgi impregnation studies showed that neurons in the scrapie-infected brains of hamsters contained varicose swellings and diminished numbers of dendritic spines. in order to ascertain whether or not these differences were statistically significant, quantitative metho ... | 1987 | 3598605 |
| scrapie associated fibrils in the diagnosis of scrapie in sheep. | previous research has consistently demonstrated by electron microscopy the presence of scrapie associated fibrils in brain extracts prepared from mice and hamsters with clinical signs of experimental scrapie. in the present study similar fibrils were seen in all the brain extracts prepared from 11 cheviot or suffolk sheep with natural or experimental scrapie that had been diagnosed clinically and confirmed neuropathologically. they were not found in the brain extracts of nine sheep that did not ... | 1987 | 3604027 |
| ultrastructural observations of spinal cord lesions and blood-brain barrier changes in scrapie-infected mice. | spinal cord samples from im or vm mice injected intracerebrally with the 87v scrapie agent were examined ultrastructurally at the clinical stage of disease for changes in blood vessel permeability and for pathological alterations. in several animals, (3 of 16), massive changes were noted in the cervical spinal cords in the subependymal area of the cortical gray matter immediately surrounding the central canal including ependymal cell changes, the presence of amyloid plaque in close association w ... | 1987 | 3604572 |
| an electron and light microscopic study of the numbers of dystrophic neurites and vacuoles in the hippocampus of mice infected intracerebrally with scrapie. | numbers of dystrophic neurites, seen with the electron microscope, in ca1 of the hippocampus of either c3h mice infected with 22c or 79a strains of scrapie, or lm mice infected with strain me7 were greater than in age-matched control mice. vacuolation, seen by light microscopy in ca1 of the hippocampus of mice infected with either 22c or 79a, preceded the increase in dystrophic neurites by up to about 20 days. in mice infected with me7, however, the vacuolation followed the increase in dystrophi ... | 1987 | 3618130 |
| cerebellar lamellar bodies in two strains of murine scrapie. | lamellar inclusion bodies have been described by other authors in the granular layer of the cerebellum of people suffering from the unconventional slow-virus disease of kuru and were thought to be associated with the disease. in this study, these bodies were also found in mice infected with scrapie, which belongs to the same group of diseases, as well as their age-matched controls. | 1987 | 3668000 |
| injury-related spinal cord astrocytes are immunoglobulin-positive (igm and/or igg) at different time periods in the regenerative process. | igg-positive astrocytes have been reported in scrapie-induced and alzheimer's cortical plaques, multiple sclerosis, and cns tissue around abscesses, metastatic tumors and primary tumors of glial origin. the present experiments ascertain if this immunoglobulin positivity is specific for these cases or a function of astrocytes around any site of injury in the cns. the spinal cords of 30, 300-g sprague-dawley male rats were lesioned by passing a 26 gauge needle through the cord at t6. after periods ... | 1987 | 3690308 |
| brain histamine metabolism in transmissible spongiform encephalopathy (scrapie). | the histamine (hi) content and the activity of l-histidine decarboxylase (hd) in brains of scrapie infected hamsters were measured. no significant changes in hi levels in particular brain areas were found when compared to controls. decreased activity of hd was found in hypothalamus (p less than 0.02). increased activity of the enzyme was observed in "rest of brain", which consisted mainly of thalamus and striatum (p less than 0.05). | 1986 | 3711883 |
| ultrastructural studies of glycoconjugates in brain micro-blood vessels and amyloid plaques of scrapie-infected mice. | lectin or glycoprotein-gold complexes and samples of scrapie-infected mouse brain embedded in lowicryl k4m were used for ultrastructural localization of glycoconjugates. the lectins tested recognize the following residues: beta-d-galactosyl [rca, ricinus communis agglutinin (aggl.) 120], n-acetyl and n-glycolyl neuraminic acid (lfa, limax flavus aggl.), n-acetyl-d-glucosaminyl and sialyl (wga, wheat germ aggl.), n-acetyl-d-galactosaminyl (hpa, helix pomatia aggl., and dba, dolichos biflorus aggl ... | 1988 | 3348084 |
| molecular cloning and complete sequence of prion protein cdna from mouse brain infected with the scrapie agent. | the prion protein (prp) is a scrapie-associated fibril protein that accumulates in the brains of hamsters and mice infected with the scrapie agent, and also in the brains of persons affected with kuru or creutzfeldt-jakob disease. it has been previously proposed that prp could be either the primary transmissible agent of scrapie or a secondary component involved in the pathogenesis of scrapie. at present, the second possibility seems more likely, for the prp-specific mrna is present in both infe ... | 1986 | 3462700 |
| properties of scrapie prion protein liposomes. | purified scrapie prions contain one identifiable macromolecule, prp 27-30, which polymerizes into rod-shaped amyloids. the rods can be dissociated with retention of scrapie infectivity upon incorporation of prp 27-30 into detergent-lipid-protein complexes (dlpc) as well as liposomes. as measured by end-point titration, scrapie infectivity was increased greater than 100-fold upon dissociating the rods into liposomes. the incorporation of prp 27-30 into liposomes was demonstrated by immunoelectron ... | 1988 | 3350818 |
| cerebrovascular amyloidosis in scrapie-affected sheep. | cerebrovascular amyloidosis (ca) was found in the cerebral and cerebellar cortices in 11 of 20 sheep, of six different breeds, with naturally-occurring scrapie. the occurrence of the lesion did not appear to be influenced by the age of the sheep. this was not seen in 20 brains from age- and breed-matched sheep with other conditions. furthermore, it was not found in 20 sheep experimentally infected with scrapie by sub-cutaneous inoculation, or in 22 sheep with natural scrapie in a closed breeding ... | 1986 | 3713984 |
| retinopathy in mice with experimental scrapie. | scrapie is a naturally occurring neurological disease of adult sheep and goats with an incubation period of several years. some strains of the causal agent can infect laboratory mice in which the incubation period, as well as the severity and distribution of vacuolar degeneration in the brain, varies according to the strain of the agent and the genotype of the mouse. retinopathy, involving the partial or complete loss of the photoreceptor layer, was observed in a number of murine scrapie models ... | 1986 | 3713985 |
| degenerative neurites in experimental scrapie. | | 1986 | 3748406 |
| molecular cloning of a human prion protein cdna. | creutzfeldt-jakob disease (cjd) of humans and scrapie of animals are degenerative, transmissible neurologic diseases caused by prions. the only known macromolecules within prions are prion proteins (prp). the cdna encoding the hamster prion protein (prp 27-30) has been cloned and sequenced (oesch et al., 1985). using that hamster prp cdna, we screened a human retina cdna library and sequenced the cdna clone with the longest hybridizing insert. this insert was found to contain a long open reading ... | 1986 | 3755672 |
| spongiform encephalopathy in sheep scrapie: electron microscopic observations. | | 1986 | 3761785 |
| [light and electron microscopic observations of sheep scrapie]. | two suffolk sheep diagnosed as scrapie clinically and epidemiologically were investigated light and electron microscopically. they were female and four years four months of age. spongiform lesions were found in the gray and white matter of midbrain, pons, medulla oblongata, spinal cord and the cerebellar white matter as well as the cerebral gray and white matter. ultrastructurally, the spongiform lesions were shown to be caused by vacuolation in neuronal perikarya, vacuolation and/or swelling of ... | 1986 | 3768187 |
| study of endemic scrapie in a flock of "ile de france" sheep. | an "ile de france" flock was studied over a period of 5 years. the authors found similar results concerning incidence and age of onset of scrapie to those found in the english literature. a close relationship was established between the age of the dam at parturition and the age of the progeny at onset of scrapie. in the later years of our study, scrapie was detected in younger animals than in the earlier years, suggesting a phenomenon of genetic "anticipation". increased fecundity in this endemi ... | 1986 | 3770148 |
| gliocytosis in experimental scrapie (263k strain of scrapie) in golden syrian hamsters. | | 1986 | 3785689 |
| chromatin structure in scrapie and alzheimer's disease. | scrapie affected brains exhibit a number of pathological features in common with the human neurodegenerative condition, alzheimer's disease. the present report describes studies on chromatin structure seen in these two disease processes. chromatin associated proteins influence transcriptional activity of dna through an effect upon chromatin structure. we examined chromatin structure by: measuring the capacity of the enzyme micrococcal nuclease to release mono- and dinucleosomes from isolated nuc ... | 1986 | 3791058 |
| primary retinopathy in scrapie in mice deprived of light. | rodents infected with some strains of scrapie develop a severe retinopathy in which the photoreceptor cells are destroyed. the possibility that this results from light-induced damage as a secondary consequence of the disease was tested by maintaining scrapie-infected albino mice in total darkness. photoreceptor loss occurred in terminal scrapie-infected mice maintained in both total darkness and in normal lighting conditions establishing that the retinopathy is a primary lesion with this strain ... | 1986 | 3808457 |
| cloning of a gene whose expression is increased in scrapie and in senile plaques in human brain. | a complementary dna library was constructed from messenger rna's extracted from the brains of mice infected with the scrapie agent. the library was differentially screened with the objectives of finding clones that might be used as markers of infection and finding clones of genes whose increased expression might be correlated with the pathological changes common to scrapie and alzheimer's disease. a gene was identified whose expression is increased in scrapie. the complementary dna corresponding ... | 1985 | 3840915 |
| creutzfeldt-jakob disease. | the historical aspects of spongiform encephalopathies, creutzfeldt-jakob disease (cjd) and kuru of man, as well as scrapie and transmissible mink encephalopathy, are outlined. transmissions of these diseases to animal hosts are presented, with emphasis on cjd transmissions to guinea pigs, hamsters, and mice. the relationship of cjd to scrapie with reference to the pathological findings is discussed. in cjd the incubation period is cut in half in guinea pigs and hamsters in the second passage. th ... | 1985 | 3880808 |
| cerebellar plaques in familial alzheimer's disease (gerstmann-sträussler-scheinker variant?). | a large kindred, with two brothers coming to autopsy, of a syndrome consisting of ataxia, dementia, and some parkinsonian features is reported; inheritance appears to be autosomal dominant. neuropathologically, there were plaques and neurofibrillary tangles in the cerebral cortex as well as some in the basal ganglia, particularly reminiscent of the plaques seen in kuru; there was only minimal spinal cord disease (pyramidal tract field). the problems of classifying this condition--alzheimer's dis ... | 1985 | 3883687 |
| oncogenes in scrapie and creutzfeldt-jacob disease. | | 1985 | 3884811 |
| degenerative neurologic disease in patients formerly treated with human growth hormone. report of the committee on growth hormone use of the lawson wilkins pediatric endocrine society, may 1985. | one or more lots of pituitary gh supplied by the nhpp may have been contaminated with cjd pathogen. if so, it is probable that the contaminated hormone was dispensed before 1978, and there is reason to believe that it was dispensed in the late 1960s. the contamination may have been limited to one lot of gh, but this is not known with certainty. purification methods used by the nhpp since 1978 probably exclude the cjd pathogen, but this is not yet certain. the risk to patients treated since 1978, ... | 1985 | 3891943 |
| [subviral infections]. | | 1985 | 3892920 |
| [human subacute spongiform encephalopathies]. | | 1985 | 3894829 |