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analysis of risk factors associated with seropositivity to neospora caninum in dogs. 200415200075
prevalence of antibodies to neospora caninum, sarcocystis neurona, and toxoplasma gondii in wild horses from central wyoming.sarcocystis neurona, neospora caninum, n. hughesi, and toxoplasma gondii are 4 related coccidians considered to be associated with encephalomyelitis in horses. the source of infection for n. hughesi is unknown, whereas opossums, dogs, and cats are the definitive hosts for s. neurona, n. caninum, and t. gondii, respectively. seroprevalence of these coccidians in 276 wild horses from central wyoming outside the known range of the opossum (didelphis virginiana) was determined. antibodies to t. gond ...200314533680
finding of neospora caninum in the wild brown rat (rattus norvegicus).nine rats (16.4%) out of 55 (rattus norvegicus) from cattle farms were seropositive to neospora caninum. two of the seropositive rats were also pcr positive but all were negative by immunohistochemistry and pas staining. the brains of all the captured rats were homogenized and initially inoculated intraperitoneally into nude mice or into spf icr mice, which had been immunosuppressed with prednisolone. one mouse that was inoculated with brain material from a seropositive rat became infected with ...200415210077
[stillbirth/perinatal weak calf syndrome in dairy heifers: results of a pilot study].a pilot study of 10 dutch dairy herds was performed to investigate possible causes of stillbirth/perinatal weak calf syndrome in heifers. possible causes and advice for further investigations on farms affected by this syndrome are discussed based on the results of investigations of blood and urine from pregnant young stock, postmortem examination of still-born calves, and a questionnaire held among farmers. infections with neospora caninum, salmonella spp. or leptospira hardjo, or a deficiency o ...200415211907
neospora caninum infection does not affect early pregnancy in dairy cattle.this study was designed to evaluate the relationship between neospora caninum infection prior to pregnancy, as determined through maternal serology, and the subsequent occurrence of abortion in dairy cattle. special emphasis was placed on pregnancy losses in the first trimester of pregnancy. neospora caninum antibodies were analyzed by commercial elisa in 2773 pregnant animals (2022 parous cows and 751 heifers) from six herds. the mean seroprevalence of antibodies to n. caninum in the herds was ...200415226015
seroprevalence of toxoplasma gondii and neospora caninum in captive maned wolves (chrysocyon brachyurus) from southeastern and midwestern regions of brazil.the main purpose of the present study was to investigate the occurrence of antibodies against t. gondii and n. caninum in captive maned wolves from brazil, considering that little information is available at the literature about infections by these parasites in this wild animal. serum samples were obtained from 59 maned wolves originated from six zoos and from one ecological reserve of the southeastern and midwestern regions of brazil. to detect igg antibodies against t. gondii, an elisa protoco ...200415262003
immune response and antigen recognition in non-pregnant ewes experimentally infected with neospora caninum tachyzoites.the cellular and humoral responses as well as the antigen recognition during the acute stage of a neospora caninum (nc) infection were investigated in non-pregnant ewes. the experimentally infected ewes developed specific lymphoproliferative and humoral responses within 2 weeks post-infection (pi). the magnitude of the cellular response showed large variations between animals. a significant decrease in the proliferative response to con a mitogen and n. caninum, toxoplasma gondii (tg) antigens wa ...200415262004
the use of pcr to detect neospora caninum dna in the blood of naturally infected cows.twelve 2-year old heifers in their fifth month of gestation when pregnancy tested were used in this study. six heifers aborted at approximately 4 months of gestation and had blood samples drawn less than 6 weeks after the abortions were identified. blood samples were also drawn from three sero-positive pregnant and three sero-negative pregnant heifers. dna was isolated from the samples and a 350 bp fragment of the nc-5 gene was pcr amplified using primer pair np21+ and np6+. also, the internal t ...200415262009
seroprevalence of neospora spp. in asymptomatic horses in italy.one hundred and fifty horses from italy were tested for serum antibodies to neospora caninum by indirect fluorescence antibody test (ifat). antibodies were present in 42 horses (28%). the positive titres were: 1:50 (16/150-10.5%), 1:100 (26/150-17%), 1:200 (8/150-5.3%) and 1:800 (1/150-0.6%). no neurological anomalies were observed in the seropositive horses. this is the first serologic survey for neospora spp. antibodies performed on horses born and raised in italy.200415265566
comparison of three techniques for the serological diagnosis of neospora caninum in the dog and their use for epidemiological studies.an enzyme-linked immunosorbent assay (elisa) was developed in our laboratory and used to determine the seroprevalence of neospora caninum in three different dog populations in belgium: healthy dogs from cattle farms and urban dogs with or without various neurological disorders. the test was validated and compared with two other tests: an indirect fluorescent antibody test (ifat) and a commercially available competitive enzyme-linked immunosorbent assay (c-elisa). the study showed a good correlat ...200415265568
prevalence of anti-neospora caninum antibodies in dogs from urban, periurban and rural areas of the city of uberlândia, minas gerais--brazil.in brazil there are few reports on the prevalence of anti-neospora caninum antibodies in dogs from urban, periurban and rural areas. serum samples from 450 dogs, 300 from urban, 58 from periurban and 92 from rural areas, were tested for the detection of anti-n. caninum igg antibodies using ifat: indirect fluorescent antibody test (ifat, > or =50). antibodies were observed in 63 (14%) of the 450 serum samples analyzed, with 32 (10.7%) in dogs coming from the urban area, 11 (18.9%) from the periur ...200415265569
clinical toxoplasma gondii, hammondia heydorni, and sarcocystis spp. infections in dogs.concurrent infections with coccidians toxoplasma gondii, sarcocystis spp., and a hammondia heydorni-like parasite were identified in tissues of three littermate pups on a kelpie dog breeding farm in australia. in total, 20 pups in four litters had died following vaccination with an attenuated distemper virus vaccine. toxoplasma gondii tachyzoites were identified immunohistochemically in tissues of two dogs. sarcocystis sp. sporocysts were seen in the intestinal lamina propria of two dogs. asexua ...200315267102
comparative analysis of stress agents in a simplified in vitro system of neospora caninum bradyzoite production.neospora caninum is an apicomplexan parasite identified as a major cause of abortion in cattle and neurological disease in various animal species. it is closely related to toxoplasma gondii, sharing the ability to persist indefinitely in latent stage within the host as a tissue cyst containing slow-dividing bradyzoites. in this study, we compared different stress methods to induce in vitro bradyzoite conversion, using marc-145 cells infected with nc-liverpool isolate. the tachyzoite-to-bradyzoit ...200415270086
characterization of pathology and parasite load in outbred and inbred mouse models of chronic neospora caninum infection.here, we analyzed histological findings and parasite burden in chronic neospora caninum infection in balb/c and icr mice and studied the correlation between lesion severity and parasite load in brain. to obtain a better understanding of the infection, we examined the influence of various host pathogen factors. groups of outbred (icr) and inbred (balb/c) mice were inoculated using several nc-1 parasite doses (4 x 10(5), 10(6), and 5 x 10(6) tachyzoites), inoculation routes (intraperitoneal and su ...200415270102
localization of a 56-kda antigen that is present in multiple developmental stages of neospora caninum.the purpose of the present study was to characterize the intracellular distribution of a native neospora caninum 56-kda protein that is recognized by sera from n. caninum-infected dairy cattle. the complementary dna coding for this protein was expressed in escherichia coli as a polyhis fusion protein to which antiserum was prepared and used to localize the antigen in n. caninum tachyzoites and bradyzoites. by sodium dodecylsulfate-polyacrylamide gel electrophoresis and immunoblotting, antirecomb ...200415270121
identification and characterization of a neospora caninum microneme-associated protein (ncmic4) that exhibits unique lactose-binding properties.microneme proteins have been shown to play an important role in the early phase of host cell adhesion, by mediating the contact between the parasite and host cell surface receptors. in this study we have identified and characterized a lectin-like protein of neospora caninum tachyzoites which was purified by alpha-lactose-agarose affinity chromatography. upon separation by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, this lactose-binding protein migrated at 70 and 55 kda under reduc ...200415271941
bovine neospora and neospora caninum: one and the same. 199715275170
placental pathology associated with fetal death in cattle inoculated with neospora caninum by two different routes in early pregnancy.pregnant cattle were inoculated with n. caninum strain nc-1 tachyzoites intravenously (iv) (group 1, n = 8) or subcutaneously (sc) (group 2, n = 8) at 70 days' gestation. control animals (group 3; n = 8) received uninfected vero cells iv. two animals from each group were killed at 14, 28, 42 and 56 days post-inoculation (dpi). fetal mortality was 100% and 50%, respectively, in groups 1 and 2 from 28 dpi. in group 1 foci of degenerative fetal placental villi were observed at 14 dpi, with clusters ...200415276854
the role of b- and t-cell immunity in toltrazuril-treated c57bl/6 wt, micromt and nude mice experimentally infected with neospora caninum.neospora caninum is a protozoan parasite predominantly known for causing abortion in cattle and neuromuscular disease in dogs. so far, no efficient metaphylactic chemotherapy has been developed. in preliminary studies, toltrazuril had been successfully used against experimental neosporosis in mice and calves. in the present study, we used immunocompetent and immunodeficient mouse strains to address the role of immunity in supporting the chemotherapy of experimental n. caninum infection. wt, micr ...200415290254
cloning, expression, and characterization of iron-containing superoxide dismutase from neospora caninum.a gene encoding superoxide dismutase (sod) from neospora caninum, a causative agent of neosporosis, has been cloned and its gene product functionally expressed and characterized. the gene had an open reading frame of 606 bp and deduced 201 amino acids. sequence analysis showed that the gene had conserved metal-binding residues and conserved amino acid residues that were found in fe-sods. comparison of the deduced amino acid sequence of the enzyme with previously reported fe-sod amino acid sequen ...200415165050
investigations into shaking mink syndrome: an encephalomyelitis of unknown cause in farmed mink (mustela vison) kits in scandinavia.an apparently novel neurological disease clinically characterized by shaking, tremors, seizures, staggering gait, and ataxia was first observed in farmed mink kits in denmark in 2000 and subsequently in sweden, denmark, and finland in 2001, and again in denmark in 2002. lymphoplasmacytic encephalomyelitis was found in the affected kits. the lesions were most severe in the brainstem and cerebellum and consisted of neuronal degeneration and necrosis, neuronophagia, focal and diffuse gliosis, periv ...200415305741
agreement between three serological tests for neospora caninum in beef cattle.during 1999, serum samples were collected from beef cows on pastures in western canada. some of the herds had a history of confirmed abortions associated with neospora caninum infection. all these samples were initially analyzed using a single application of 1 common commercial enzyme-linked immunosorbent assay (elisa) for antibodies to n. caninum. from these initial results, 239 positive and 250 negative samples were randomly selected for further testing. this group of samples was retested usin ...200415305742
sero-epidemiological survey of neospora caninum infection in dogs in north-eastern italy.risk factors associated with neospora caninum seroprevalence in north-eastern italy in healthy dogs were assessed. antibodies to n. caninum were found in 10.9% of 707 kennel and owned dogs by a commercial competitive elisa (vmrd inc.). all dogs were negative for leishmania infantum by indirect fluorescent antibody test indicating no cross reactivity or association between the two protozoa in this area. seroprevalence association with breed and age of dogs and other factors are discussed.200415325040
effect of a killed whole neospora caninum tachyzoite vaccine on the crude abortion rate of costa rican dairy cows under field conditions.a standard field trial was carried out to assess the effect of a commercial neospora-vaccine based on whole killed tachyzoites (bovilis-neoguard, intervet) on the abortion rate. eight hundred and seventy-six cows, over 2.5 months pregnant, belonging to 25 costa rican dairy herds, were used in the analysis. for each cow vaccinated, a cow of the same herd, breed and age category, was selected as control. the period of administration of treatments extended from june to november of 2000. the treatme ...200415325041
prevalence of anti-toxoplasma gondii and anti-neospora caninum antibodies in ovine from são paulo state, brazil.serum samples from 597 sheep from são paulo state, in the southeastern region of brazil, were tested to determine the prevalence of antibodies directed against toxoplasma gondii (> or = 1:64) and neospora caninum (> or = 1:50) using the indirect fluorescent antibody test (ifat). the animals were divided into three groups based on their age: < or = 1 year, 1-4 years, and > or = 4 years. antibodies to t. gondii were observed in 34.7% of the samples with titers ranging from 64 to 16,384 and igg ant ...200415325042
detection of neospora caninum in an aborted goat foetus.in italy neospora caninum has been reported in cattle, in buffaloes and in dogs. no data are available about the infection in sheep and goats. in this paper, the authors report the detection of protozoan cysts, identified as n. caninum by pcr, in the brain of an aborted goat foetus.200415325053
detection of antibodies to neospora caninum in two species of wild canids, lycalopex gymnocercus and cerdocyon thous from brazil.domestic dog (canis domesticus) and the coyote (canis latrans) are the only known definitive hosts for the protozoan neospora caninum that causes abortion in dairy cattle. in the present study, antibodies to n. caninum were sought in three species of wild canids, cerdocyon thous, lycalopex gymnocercus and dusicyon vetulus from brazil. antibodies to n. caninum were assayed by the indirect fluorescent antibody test (ifat) and the neospora agglutination test (nat). n. caninum antibodies were found ...200415325054
prevalence of neospora caninum infection in dairy cows and its consequences for reproductive management.this study was carried out to determine the prevalence of neosporosis in an area of intensive dairy production, in portugal. sera samples were obtained in a random basis from 114 cows in 49 herds (group a), and from 1237 cows in 36 herds with a history of abortion outbreaks (group b). all sera samples were tested for neosporosis by direct agglutination test (dat). additionally, attempts to isolate neospora caninum in 42 aborted bovine fetuses from 38 dairy herds (group c) were carried out, utili ...200415325549
occasional detection of neospora caninum dna in frozen extended semen from naturally infected bulls.recently, the presence of neospora caninum dna in semen from naturally infected bulls was reported. in the present work, the presence and quantification of n. caninum by pcr techniques in frozen extended semen straws from naturally infected bulls was investigated. a total of 20 seropositive and five seronegative bulls raised for reproductive purposes in an ai centre were used. ten extended semen straws from each bull obtained at different time-points during the previous 2 years were selected for ...200415325558
udder health in dairy cattle infected with neospora caninum.blood samples were collected from 3449 cows on 57 representative ontario dairy herds during the summer of 1998 and analysed for antibody to neospora caninum using an elisa. forty-eight herds (2742 cattle) contained at least one n. caninum-seropositive animal. two composite milk samples were collected from all cattle: the first on the day of blood collection and the second 68 to 365 days later. all milk samples were submitted for bacteriological culture. ontario dairy herd improvement corporation ...200415325765
prevalence of neospora caninum antibodies and factors associated with their presence in dairy cattle of the north of paraná state, brazil.to determine the prevalence of neospora caninum antibodies and associated factors, blood sera from 623 female dairy cattle from 23 farms in the north of the state of paraná, brazil, were analyzed by means of the indirect immunofluorescent-antibody test (ifat > or = 25). serum samples from 134 dogs living on the same farms also were tested for n. caninum antibodies (ifat > or = 50), and the presence of dogs was associated with the prevalence of n. caninum antibodies in cattle. the overall seropre ...200415350656
neospora caninum infection in breeder bulls: seroprevalence and comparison of serological methods used for diagnosis.to investigate the seroprevalence of neospora caninum infection in breeder bulls. in addition, the level of agreement of serological methods used was evaluated.200415350658
first isolation of neospora caninum from an aborted bovine fetus in spain.neospora caninum was isolated from the brain of a 6-mo-old aborted bovine fetus from galicia, spain. the fetal brain homogenate was inoculated intraperitoneally into cortisonized mice. the peritoneal exudate from the infected mice, along with mouse sarcoma cells (tg180), was inoculated into a second group of mice, and parasites were harvested from the peritoneal exudate. the parasites were adapted to in vitro growth in vero monolayers. the tachyzoites from the peritoneal exudate reacted positive ...200415357083
first report of neospora caninum infection in adult alpacas (vicugna pacos) and llamas (lama glama).neospora caninum is a cyst-forming coccidian that mainly affects bovines, although neospora infection has also been described in other domestic and wild ruminant species. serum samples from 78 alpacas (vicugna pacos) and 73 llamas (lama glama) at a unique dilution of 1:50 tested by indirect fluorescent antibody test (ifat) were further analyzed serologically by ifat and western blot in both ruminant species to avoid cross-reactions with closely related coccidian parasites and to confirm the exis ...200415357084
recognition patterns of neospora caninum tachyzoite antigens by bovine igg at different ifat titres.this study describes qualitative and quantitative antibody response in cows naturally infected with neospora caninum. the study was carried out with 269 serum samples obtained from 24 cows over a period of 15 weeks. prior to sample collection, the cows were tested with elisa. the 269 samples were screened with ifat and categorized into seven ifat titre groups (< 1 : 80, 1 : 80, 1 : 200, 1 : 600, 1 : 1000, 1 : 2000, > 1 : 2000). the samples were finally analysed by western blotting. seven immunod ...200415367295
two-dimensional gel electrophoresis and immunoblot analysis of neospora caninum tachyzoites.identification of expressed protein profiles and antigenic determination are some of the most challenging aspects of proteomics. two-dimensional gel electrophoresis (2-de) combined with immunoblot analysis were employed to study the n. caninum proteome. protein sample preparation was carried out by first conducting sonication, followed by adding lysis buffer containing 7m urea plus 2m thiourea to the purified tachyzoites in order to complete disruption. a total of 335 differentially expressed pr ...200415192341
shedding of neospora caninum oocysts by dogs fed tissues from naturally infected water buffaloes (bubalus bubalis) from brazil.attempts were made to isolate neospora caninum from naturally infected water buffaloes (bubalus bubalis) from brazil. brains from six buffaloes with indirect fluorescent antibodies (>1:100) to n. caninum were used to isolate the parasite by bioassay in dogs and gerbils followed by in vitro culture. shedding of neospora-like oocysts was noticed in dogs fed brains from three buffaloes (isolate designation ncbrbuf-1, 2 and 4). two more isolates (ncbrbuf-3 and 5) were obtained by in vitro culture of ...200415381294
serological prevalence of neospora caninum in healthy and aborted dairy cattle in mashhad, iran.a total of 810 dairy cattle were blood sampled and used to evaluate serological screening for neospora caninum infection in dairy cattle herds in mashhad (khorasan province, iran). in 4 herds, of the 810 cattle, 123 (15.18%) were seropositive by ifa test (vmrd inc., pullman, wa 99163, usa) with titer 1:200 and range of prevalence per herd from 9.92 to 19.60%. seroprevalence was not significantly different between holstein breed (14.88%) and brown swiss breed (19.60%). comparison of n. caninum se ...200415381300
identification of antigenic proteins from neospora caninum recognized by bovine immunoglobulins m, e, a and g using immunoproteomics.antigenic proteins of neospora caninum (n. caninum) against bovine immunoglobulins m, e, a, and g were investigated by using immunoproteomics. proteins of n. caninum (kba-2) tachyzoite lysates separated by two-dimensional gel electrophoresis were transferred to polyvinylidene difluoride (pvdf) membranes, probed with different bovine immunoglobulin class and classified. antigenic spots recognized were also identified by matrix-assisted laser desorption/ionization-time of flight-mass spectrometry ...200415449377
neosporosis.neospora caninum is a recently recognized protozoan parasite of animals, which, until 1988, was misdiagnosed as toxoplasma gondii. neospora caninum or neospora-like parasites, here discussed by j.p. dubey and david lindsay, cause paralysis and death in dogs and neonatal mortality and abortion in cattle, sheep, goats and horses.199315463690
potential risk factors for bovine neospora caninum infection in germany are not under the control of the farmers.in the german state of rhineland-palatinate, herds were identified that were likely to have a neospora caninum sero-prevalence > or = 10% by using a bulk milk elisa. individual herd data were obtained by a questionnaire. univariate logistic regression showed that bulk milk positive farms had a significantly higher chance to report an increased abortion rate than negative farms (p(wald)<0.1). the chance to have a bulk milk positive herd increased with the minimum number of years a farm had report ...200415471005
anti-protozoal efficacy of high performance liquid chromatography fractions of torilis japonica and sophora flavescens extracts on neospora caninum and toxoplasma gondii.we previously reported that alcoholic extracts of sophora flavescens and torilis japonica from south korea demonstrated good efficacy in reducing replication of toxoplasma gondii and neospora caninum. to characterize the chemical component associated with anti-protozoal activity, specific fractions were isolated by high performance liquid chromatography (hplc) and used for in vitro testing. these fractions were evaluated in vitro against t. gondii and n. caninum. fractions of the herb extracts w ...200415482896
genetic susceptibility to neospora caninum infection in holstein cattle in ontario.neospora caninum has been reported to be an important cause of endemic fetal loss and occasional abortion epidemics in cattle around the world. this study examined 12,016 sera collected from 9723 holstein cows on 125 herds across ontario in 1998, 1999, and 2000. an enzyme-linked immunosorbent assay was used to examine the sera for antibodies to n. caninum. the overall prevalence of n. caninum antibodies in the cattle was 11.2% and the prevalence in individual herds varied from 0 to 70.4%. among ...200415483182
meningoencephalomyelitis caused by neospora caninum in a juvenile fallow deer (dama dama).neosporosis, caused by the protozoan parasite neospora caninum, is a serious cause of bovine abortion, stillbirth and perinatal death. this paper reports a clinical neosporosis in a 3-week-old fallow deer (dama dama). the fawn was full term and appeared normal at birth. histological lesions consisted of a multifocal necrotizing and granulomatous meningoencephalomyelitis, with intralesional protozoal cysts. positive immunohistochemical staining and characteristic pcr products confirmed the diagno ...200415485563
establishment of neospora caninum antigen-specific t cell lines of primarily cd4 t cells.neosporosis is an important cause of pregnancy loss in cattle worldwide. protective immunity against neospora caninum infection may include both cell-mediated (cmi) and humoral immune responses. this study was to establish short-term antigen-specific t cell lines composed of primarily cd4(+)t cells from peripheral blood lymphocytes (pbl) of infected cows, which may be used to identify immunodominant antigens for the development of n. caninum vaccines. crude n. caninum tachyzoite antigen was prep ...200415491474
detection of the protozoan neospora caninum using in situ polymerase chain reaction.a new method to detect the protozoan neospora caninum using indirect in situ polymerase chain reaction (pcr) is described. in situ pcr combines the advantages of the extraordinarily high sensitivity and specificity of pcr and the in situ representation of immunohistochemical methods. we describe an indirect in situ pcr, whereby the amplified products were detected using a primed in situ (prins) reaction with hapten-labeled nucleotides and visualized using fluorochrome-labeled antibodies. this te ...200415513712
hammondia heydorni: evidence of genetic diversity among isolates from dogs.canine isolates of hammondia heydorni from argentina, brazil, and the united states were analysed for genetic diversity. a total of 14 isolates were tested for their ability to produce amplification using three pcr assays, one targeting the common toxoplasmatiid its-1 region and 2 amplifying novel, h. heydorni-specific loci, hhap7 and hhap10. while the its-1 fragments could be amplified from all isolates, only six isolates were capable of amplifying the fragments from the novel loci. the pcr pro ...200415208039
evaluation of vaccination with neospora caninum protein for prevention of fetal loss associated with experimentally induced neosporosis in sheep.to evaluate the immunologic response of a killed tachyzoite vaccine against neospora caninum and its effectiveness in preventing fetal loss associated with experimentally induced neosporosis in sheep.200415524328
neospora-associated abortion episode over a 1-year period in a dairy herd in north-east spain.this report describes a retrospective study based on serological screening, performed on a neospora-associated abortion episode over a 12-month period in a dairy herd in north-east spain. during the 1-year study period, the overall abortion rate for the herd was 23.2% (38 abortions of 164 diagnosed pregnancies). the data analysed were those derived from blood samples collected from the whole herd (n = 237) and from diagnosed pregnancies. antibodies to neospora caninum were found in 35.4% of the ...200415525363
tissue culture and explant approaches to studying and visualizing neospora caninum and its interactions with the host cell.neospora caninum is an apicomplexan parasite first mentioned in 1984 as a causative agent of neuromuscular disease in dogs. it is closely related to toxoplasma gondii and hammondia heydorni, and its subsequent description in 1988 has been, and still is, accompanied by discussions on the true phylogenetical status of the genus neospora. n. caninum exhibits features that clearly distinguish this parasite from other members of the apicomplexa, including distinct ultrastructural properties, genetic ...200415525434
alternative mechanism of eimeria bovis sporozoites to invade cells in vitro by breaching the plasma membrane.in vitro eimeria bovis sporozoites invade a wide range of cell types, and in the case of bovine cells, they may develop to first-generation schizonts. often, however, they subsequently leave their host cell to invade a new one, which seems contrary to the classical way of infecting a cell by forming a parasitophorous vacuole. using a standard, "cell wound assay," we show that e. bovis can invade bovine endothelial cells by breaching the plasma membrane and may again leave the surviving cell. eim ...200415562619
molecular and biological characterization of hammondia heydorni-like oocysts from a dog fed hearts from naturally infected white-tailed deer (odocoileus virginianus).neospora caninum and hammondia heydorni are morphologically and phylogenetically related coccidians that are found in dogs. although there is serological evidence of n. caninum infection in the white-tailed deer (odocoileus virginianus), the parasite has not been yet isolated from the tissues of this host. in an attempt to isolate n. caninum from deer, hearts from 4 deer with antibodies to n. caninum were fed to 2 dogs. one of these dogs shed unsporulated oocysts 12-14 microm in diameter. sporul ...200415562623
applying biotin-streptavidin binding for iscom (immunostimulating complex) association of recombinant immunogens.we have previously reported strategies for escherichia coli production of recombinant immunogens fused to hydrophobic peptide or lipid tags to improve their capacity to be incorporated into an adjuvant formulation. in the present study, we have explored the strong interaction between biotin and sa (streptavidin) (k(d) approximately 10(-15) m) to couple recombinant immunogens to iscoms (immunostimulating complexes). two different concepts were evaluated. in the first concept, a his(6)-tagged sa f ...200515296488
prevalence of antibodies to neospora caninum in local and imported cattle breeds in the kars province of turkey.this study investigates the seroprevalence of neospora caninum in cattle in the province of kars in north-eastern turkey. a total of 301 serum samples, 228 from local breeds of cows with a history of recent abortion and the remaining 73 collected at random from simmental cows imported from germany or their offspring, were tested for anti-neospora antibodies by elisa. all the serum samples from local breeds were negative for n. caninum antibodies, apart from one which tested inconclusive. in cont ...200515563918
acute toxoplasmosis in three wild arctic foxes (alopex lagopus) from svalbard; one with co-infections of salmonella enteritidis pt1 and yersinia pseudotuberculosis serotype 2b.acute disseminated toxoplasmosis was diagnosed in three wild arctic foxes (alopex lagopus) that were found dead in the same locality on svalbard (norway). the animals included one adult female and two 4-months-old pups. the adult fox was severely jaundiced. necropsy revealed multifocal, acute, necrotizing hepatitis, acute interstitial pneumonia, and scattered foci of brain gliosis, often associated with toxoplasma tachyzoites. one pup also had toxoplasma-associated meningitis. in addition, the l ...200515563924
an interlaboratory comparison of immunohistochemistry and pcr methods for detection of neospora caninum in bovine foetal tissues.seven european laboratories contributed to a multi-centre evaluation of detection techniques for neospora caninum in bovine foetuses. six laboratories participated in immunohistochemistry (ihc) testing. all seven laboratories participated in pcr testing, but the results from one laboratory were not included in the analysis, because of contamination problems in the preparation of the samples. a coded panel of tissue sections from 36 infected and non-infected foetuses was used to evaluate the ihc ...200415567040
elaboration of a crude antigen elisa for serodiagnosis of caprine neosporosis: validation of the test by detection of neospora caninum-specific antibodies in goats from sri lanka.the protozoan parasite n. caninum is a major pathogen in cattle and dogs. however, clinical symptoms are occasionally described for other potential hosts. natural abortion in goats due to n. caninum has been rarely reported and only little data is available on the seroprevalence of n. caninum in this species. in the present study, 486 goats from sri lanka were tested in a crude antigen elisa for the presence of serum antibodies against n. caninum. additionally, the sera were analysed by n. canin ...200415567589
isolation of neospora caninum from a calf in malaysia.in order to attempt isolate the protozoan parasite neospora caninum, an n. caninum seropositive pregnant sahiwal friesian cross heifer from a large-scale dairy farm in malaysia was kept for observation until parturition at the veterinary research institute, ipoh. the heifer gave birth to a female calf that was weak, underweight and unable to rise. precolostral serum from the calf had an n. caninum indirect fluorescent antibody test titre of 1:3200. it died 12 h after birth and necropsy was perfo ...200415567590
cross-sectional survey in pig breeding farms in hesse, germany: seroprevalence and risk factors of infections with toxoplasma gondii, sarcocystis spp. and neospora caninum in sows.a cross-sectional survey was performed to estimate the prevalences of antibodies to toxoplasma gondii (elisa, ifat), sarcocystis spp. (elisa, using s. miescheriana as antigen) and neospora caninum (elisa, immunoblotting) in sows from breeding farms in southern hesse, germany. a total of 2041 plasma samples of sows from 94 randomly selected farms was examined. data on farm profiles, husbandry management and sows were collected by a questionnaire and exploratively analysed. for t. gondii the elisa ...200415567591
biologic, morphologic, and molecular characterisation of neospora caninum isolates from littermate dogs.isolation and biologic and molecular attributes of neospora caninum from three littermate dogs are described. tissue cysts were confined to the brain and striated muscles. n. caninum was isolated (isolates nc-6, nc-7, and nc-8) in rodents and cell culture that had been inoculated with brain tissue from the dogs. schizont-like stages reactive with n. caninum antibodies were seen in cell cultures seeded with bradyzoites released from percoll-isolated n. caninum tissue cysts from the brain of one d ...200415380687
gerbil model of acute neosporosis.experimental infections with the nc-1 strain of neospora caninum were conducted in gerbils (meriones unguiculatus) to determine their acute responses to experimental intraperitoneal infection. five groups of five female gerbils were used and they were intraperitoneally infected with 1x10(6), 2x10(6), 3x10(6), 4x10(6) or 5x10(6) tachyzoites. gerbils in all groups developed clinical signs of neosporosis which consisted of inactivity 4-5 days post-inoculation. morbidity and mortality were observed ...200515631903
application of proteomics for comparison of proteome of neospora caninum and toxoplasma gondii tachyzoites.protein profiles of two isolates of neospora caninum (kba-2 and jpa1) and toxoplasma gondii rh strain were investigated by proteomic approach. approximately, 78% of protein spots on two-dimensional gel electrophoresis (2-de) profiles and 80% of antigen spots on 2-de immunoblotting profiles were exhibited to share the same pi and m(r) between kba-2 and jpa1 of n. caninum. on the other hand, a total of 30 antigen spots of t. gondii were recognized on 2-de immunoblotting profile using rabbit antise ...200515652819
canine inflammatory myopathies: a clinicopathologic review of 200 cases.a retrospective study was performed on 200 randomly selected cases of inflammatory myopathy in dogs from diagnostic muscle biopsies received at the comparative neuromuscular laboratory, university of california, san diego. the most common clinical signs in dogs diagnosed with an inflammatory myopathy were generalized weakness, stilted gait, dysphagia, masticatory or generalized muscle atrophy, inability to open the jaw, megaesophagus, and dysphonia. myalgia was rarely described. age of onset ran ...200415515585
adaptation of a surface antigen-based elisa for the detection of antibodies against neospora caninum in bovine milk.the aim of the present study was to determine whether an elisa based on a 38-kda surface antigen (ncsrs2) of neospora caninum tachyzoites could be used to examine bovine milk for antibodies against n. caninum. a total of 797 undiluted milk samples from n. caninum-infected herds were examined in the p38-elisa. milk results of individual animals were compared with those obtained by the same elisa for the corresponding serum samples. the linear correlation between milk and serum antibody results of ...200515703000
neospora caninum infection does not affect the fertility of dairy cows in herds with high incidence of neospora-associated abortions.this present study, was designed to establish whether neospora caninum infection affects the fertility of high-producing dairy cows, and was based on yearly serological screening for neosporosis and on the confirmation of n. caninum infection in aborted foetuses. assessment was made of 7518 artificial inseminations (ai) (applied to parous cows) performed in three herds. of these inseminations, 2540 (33.8%) resulted in pregnancy; 34% of which corresponded to seronegative cows (2226 of 6556 ai per ...200515703002
risk factors associated with neospora caninum abortion in ontario holstein dairy herds.the objective of this epidemiological study was to identify risk factors for neospora caninum-related abortions in ontario holstein dairy herds. a total of 88 herds, consisting of 5080 cattle, and utilizing dairy herd improvement (dhi) services, were divided into three groups. case (n = 30) and first control (n = 31) herds were selected from 1998 and 1999 fetal abortion submissions to the animal health laboratory, university of guelph, that were histopathologically positive or negative, respecti ...200515710518
transmission of neospora caninum between wild and domestic animals.to determine whether deer can transmit neospora caninum, brains of naturally infected white-tailed deer (odocoileus virginianus) were fed to 4 dogs; 2 of these dogs shed oocysts. oocysts from 1 of the dogs were tested by polymerase chain reaction and found to be positive for n. caninum and negative for hammondia heydorni. the internal transcribed spacer 1 sequence of the new strain (designated nc-deer1) was identical to n. caninum from domestic animals, indicating that n. caninum is transmitted ...200415715229
transplacental transmission and abortion in cows administered neospora caninum oocysts.neospora caninum infection is a common cause of bovine abortion. one method by which cattle can acquire infection is through ingestion of oocysts; however, this has not yet been proved to cause transplacental infection or abortion. in this study, 19 cows, pregnant between 70 and 176 days, were administered 1500 to 115,000 oocysts through an esophageal tube. seventeen of the cows became seropositive, indicating acquisition of infection, whereas 8 negative control cows remained seronegative (p < 0 ...200415715235
detection of neospora caninum in the semen and blood of naturally infected bulls.a prospective study was designed to investigate the presence of neospora caninum in semen and blood of eight bulls seropositive to n. caninum using nested-pcr procedures. positive semen and blood samples were bioassayed in a balb/c nu/nu mouse model. specific anti-n. caninum serological and interferon-gamma (ifn-gamma) responses were also studied. in parallel, five seronegative bulls acted as non-infected controls. all bulls were located in a collaborating ai centre and monitored for 22 weeks. s ...200515725454
cross-reactivities with cryptosporidium spp. by chicken monoclonal antibodies that recognize avian eimeria spp.in a previous study, we have developed several chicken monoclonal antibodies (mabs) against eimeria acervulina (ea) in order to identify potential ligand molecules of eimeria. one of these mabs, 6d-12-g10, was found to recognize a conoid antigen of ea sporozoites and significantly inhibited the sporozoite invasions of host t lymphocytes in vitro. furthermore, some of these chicken mabs showed cross-reactivities with several different avian eimeria spp. and the mab 6d-12-g10 also demonstrated cro ...200415725532
antibodies to neospora caninum in the blood of european bison (bison bonasus bonasus l.) living in poland.the prevalence of antibodies to neospora caninum was examined in european bison (bison bonasus bonasus l.) living in free and fenced areas in poland. sera of 320 european bison, different ages and sexes, from breeding areas in poland were tested for n. caninum antibodies using elisa test. positive antibody responses were found in 23 bison (prevalence 7.3%). additionally, all positive sera were tested by western blot to verify the elisa results. the western blot results confirmed the presence of ...200415725547
identification of vaccine candidate peptides in the ncsrs2 surface protein of neospora caninum by using cd4+ cytotoxic t lymphocytes and gamma interferon-secreting t lymphocytes of infected holstein cattle.previously, our laboratory showed that holstein cattle experimentally infected with neospora caninum develop parasite-specific cd4+ cytotoxic t lymphocytes (ctl) that lyse infected, autologous target cells through a perforin-granzyme pathway. to identify specific parasite antigens inducing bovine ctl and helper t-lymphocyte responses for vaccine development against bovine neosporosis, the tachyzoite major surface proteins ncsag1 and ncsrs2 were targeted. in whole tachyzoite antigen-expanded bovi ...200515731029
neosporosis in a young dog presenting with dermatitis and neuromuscular signs.a 16-week-old, male boxer dog developed multifocal nodular dermatitis followed by rapidly progressive and fatal neuromuscular disease. protozoal tachyzoites were demonstrated by aspiration and biopsy of dermal lesions. necropsy and histology revealed necrotising inflammation associated with intralesional protozoal organisms in various organs including the brain, heart, skeletal muscle and skin. serology suggested active infection with neospora caninum. immunohistochemistry provided a definitive ...200515736815
prevalence of antibodies against neospora caninum and toxoplasma gondii in dogs and foxes in austria.sera from 1770 dogs and 94 red foxes from austria were examined for antibodies against neospora caninum using the indirect immunofluorescent antibody test (ifat). 3.6% of the dogs were seropositive with titres ranging from 1:50 to 1:6400. dogs from rural areas were significantly more often seropositive for n. caninum than those from the urban area of vienna (5.3% versus 2.1%). there were no significant differences in sex or breed, but a slight increase in seropositivity with age was apparent, in ...200515740855
igg avidity pattern in cattle after ingestion of neospora caninum oocysts.the avidity (functional affinity) of specific antibodies are being used to estimate duration of bovine neospora caninum infection. here, we report for the first time the avidity pattern in cattle orally inoculated with n. caninum oocysts. in all, 16 pregnant cows and 7 calves were administered n. caninum oocysts. in the cows, the avidity increased during the early course of infection. in all but one, the avidity was < or = 35 during the first 6 weeks after infection and no cow had an avidity val ...200515740856
prevalence and transmission of neospora caninum within infected swedish dairy herds.in this long-term study, the changes in within-herd neospora caninum seroprevalences and the relative importance of horizontal and vertical parasite transmission in swedish dairy herds were investigated. the within-herd prevalences varied between 5.8% and 65.0% when the herds were first sampled. comparing the prevalences of year 2000 with those found 2-3 years later, nine out of 14 investigated herds had a similar or lower within-herd prevalence while five herds had an increased portion of serop ...200515740858
neospora caninum in pastured cattle: determination of climatic, environmental, farm management and individual animal risk factors using remote sensing and geographical information systems.a cross-sectional serological survey was conducted on cattle pasturing in an area of the southern italian apennines to evaluate the seroprevalence to neospora caninum, and to investigate the climatic, environmental, farm management, and individual animal factors that influence the distribution of this protozoan. blood samples were collected from 864 pastured cattle raised on 81 farms. serum samples were tested for antibodies to n. caninum using an elisa assay (herdcheck), idexx). a geographical ...200515740859
neospora abortions in dairy cattle: diagnosis, mode of transmission and control.to determine the contribution of neospora caninum to abortions on a dairy farm in nsw (australia), determine the mode of transmission and develop and trial a control option for infection.200515740860
the use of beef bull semen reduced the risk of abortion in neospora-seropositive dairy cows.there is an evidence that the epidemiology of neosporosis differs in dairy and beef cattle, such that beef cattle carry a lower risk of abortion. the aim of the present study was to establish whether artificial insemination using semen from beef bulls could reduce the risk of abortion in dairy cows seropositive for the neospora caninum parasite. our study was based on yearly serological screening for neosporosis and on the confirmation of neospora infection in aborted fetuses in two high-produci ...200515752268
toltrazuril treatment to control diaplacental neospora caninum transmission in experimentally infected pregnant mice.we addressed the question whether diaplacental transmission of neospora caninum can be controlled by metaphylactic chemotherapy using toltrazuril or enrofloxacin. female c57/bl6 mice, infected on day 10 of pregnancy, were medicated for 6 consecutive days p.i. with 52.5 mg toltrazuril or - as an out-group control medication--16.7 mg enrofloxacin per kg body weight per day. other control groups received either infection but no medication or vice versa. toltrazuril treatment significantly reduced p ...200515700756
global protein expression analysis in apicomplexan parasites: current status.members of the phylum apicomplexa are important protozoan parasites that cause some of the most serious, and in some cases, deadly diseases in humans and animals. they include species from the genus plasmodium, toxoplasma, eimeria, neospora, cryptosporidium, babesia and theileria. the medical, veterinary and economic impact of these pathogens on a global scale is enormous. although chemo- and immuno-prophylactic strategies are available to control some of these parasites, they are inadequate. cu ...200515759314
seroprevalence of antibodies against bovine leukemia virus, bovine viral diarrhea virus, mycobacterium avium subspecies paratuberculosis, and neospora caninum in dairy cattle in saskatchewan.blood was drawn from 1530 dairy cows in 51 herds. for antibodies against bovine leukemia virus, mycobacterium avium subspecies paratuberculosis, and neospora caninum, 37.4%, 2.7%, and 5.6% of cows were test positive, respectively, while 29.2% of herds had unvaccinated animals with > or = 1:64 for bovine viral diarrhea virus.200515759829
monoclonal antibodies preventing invasion of neospora caninum tachyzoites into host cells.twelve monoclonal antibodies (mabs) against neospora caninum tachyzoites were produced to specify the antigens related to the invasion of tachyzoites into host cells. in the assay to evaluate the inhibition activity, all these mabs prevented the cultured vero cells from the invading by the tachyzoites. these mabs recognized approximately a 73 kda antigen in western blot analysis. immunofluorescence assay and immune electron microscopy revealed that this 73 kda antigen is a part of the surface an ...200415585948
incidence of abortion and association with putative causes in dairy herds in new zealand.to estimate the distribution and causes of abortion in dairy herds across new zealand during the 2001/2002 breeding season.200415768103
general strategies for efficient adjuvant incorporation of recombinant subunit immunogens.we have previously reported strategies for escherichia coli production of recombinant immunogens fused to hydrophobic peptides or lipid tags to improve their capacity to be incorporated into an adjuvant formulation, e.g., immunostimulating complexes (iscoms). recently, we also explored the strong interaction between biotin and streptavidin to achieve iscom association of recombinant immunogens. plasmodium falciparum,toxoplasma gondii and neospora caninum antigens have served as model immunogens ...200515755622
[first documentation of a neospora-induced "abortion storm" (exogenous transplacental transmission of neospora caninum) in a swiss dairy farm].in a swiss dairy farm (canton of geneva) consisting of 73 animals 8 abortions were observed within 2 weeks. serological and molecular biological analyses (pcr) on aborting dams, and abortion materials, respectively, revealed that the protozoan parasite neospora caninum was the causative agent. besides the 8 aborting animals, 12 other non-aborting heifers were found to be serologically positive for this parasite. all positive sera were further tested in an avidity-elisa to elucidate the recency o ...200515801622
evaluation of a pcr based on primers to nc5 gene for the detection of neospora caninum in brain tissues of bovine aborted fetuses. 200415563105
serological responses to neospora caninum in experimentally and naturally infected water buffaloes (bubalus bubalis).the water buffalo (bubalus bubalis) is an important natural host for neospora caninum. serologic responses to n. caninum were studied in experimentally and naturally infected water buffaloes in brazil. antibodies were assayed by the indirect fluorescent antibody test (ifat) using a cut off value of 1:25. six buffaloes were each inoculated subcutaneously with 5 x 10(6) live culture-derived tachyzoites of the cattle illinois strain of n. caninum, and two calves were kept as uninoculated controls. ...200515817198
immunisation of mice against neosporosis with recombinant ncsrs2 iscoms.the coccidian parasite neospora caninum is an intracellular protozoan, causing abortion in cattle in many countries around the world. in this study, the protective potential of the major n. caninum surface antigen ncsrs2, expressed in escherichia coli and formulated into immunostimulating complexes (iscoms), was investigated in an experimental mouse model. the recombinant protein was specially designed for binding to iscoms via biotin-streptavidin interaction. two groups of 10 balb/c mice were i ...200515817199
relationship between type 1/type 2 immune responses and occurrence of vertical transmission in balb/c mice infected with neospora caninum.to examine the relationship between occurrence of vertical transmission and type 1/type 2 immune responses induced by neospora caninum infection in balb/c mice, pregnant (group 1 p) and non-pregnant mice (group 1 np) were inoculated with 2 x 10(6) of the n. caninum parasites and then we examined the vertical transmission rate and production of ifn-gamma and il-4. we also studied chronically infected mice, which were bred at 4 weeks or more after infection (group 2), and mice inoculated during pr ...200515817216
immune responses during pregnancy in heifers naturally infected with neospora caninum with and without immunization.this study was designed to identify changes in parasite-specific immune responses that occur during vertical transmission of neospora caninum and can be used as indicators of parasite reactivation in naturally infected heifers. ten heifers were unimmunized and 11 immunized with killed tachyzoites. one unimmunized heifer, which aborted at week 19 of gestation, had an increase in parasite-specific antibodies, mainly igg(2), from week 15 to week 19 and a concomitant decline in parasite-specific cel ...200515841416
feline cutaneous toxoplasmosis: a case report.a 9-year-old female, domestic short hair cat was presented with sudden onset of polyuria/polydipsia, and hundreds of cutaneous nodules. prior to referral, the cat had had four skin nodules that were treated with steroids. the four skin nodules then multiplied to form more than 100 ulcerated and nonulcerated nodules located all over the trunk. clinical evaluation revealed hypothermia and respiratory distress. cytology from both skin nodules and bronchoalveolar lavage showed macrophages and small ...200515842545
isolation of neospora caninum from naturally infected white-tailed deer (odocoileus virginianus).attempts were made to isolate neospora caninum from naturally infected white-tailed deer (odocoileus virginianus). a total of 110 deer killed during the 2003 hunting season in virginia region were used for the isolation of n. caninum. of these, brains from 28 deer that had nat titer of 1:200 were inoculated into interferon-gamma gene knock out (ko) mice. n. caninum was isolated from the tissues of three deer and all three isolates were mildly virulent to ko mice. only one of the isolates could b ...200515845280
occurrence of anti-neospora caninum antibodies in brazilian cervids kept in captivity.neospora caninum is a coccidian parasite that causes disease in captive and domesticated animals and has been found in wild animals such as cervids. sera from 150 cervids of the genus mazama, were collected from 31 captive herds and 16 zoos from different brazilian regions and analyzed by indirect fluorescent antibody test for anti-n. caninum antibodies. positive reactions were found in 42% (63) of the samples and the titers varied from 50 to 51,200. of the 86 cervids from the captive herds, 38 ...200515845290
associations between pregnancy outcome and serological response to neospora caninum among a group of dairy heifers.to monitor pregnancy in a group of rising 2-year-old dairy heifers on a farm on which abortion due to neospora caninum was known to occur in previous years.200515846399
autofluorescence of toxoplasma gondii and neospora caninum cysts in vitro.autofluorescence of toxoplasma gondii and neospora caninum was studied by fluorescence microscopy during their differentiation from tachyzoites to bradyzoites in vitro using vero as host cells. stage conversion into bradyzoites and cysts was confirmed by immunofluorescent microscopy and western blot analysis using sag1- and bag1-specific antibody, respectively. from day 4 postinfection (pi), pale blue autofluorescence of the bradyzoites and tissue cysts was observed with uv light at 330-385 nm, ...200515856866
detection of antibodies to neospora caninum in cattle by enzyme-linked immunosorbent assay with truncated ncsrs2 expressed in escherichia coli.the surface antigen 1-related sequence 2 of neospora caninum (ncsrs2) is considered as an immunodominant antigen. in this study, the gene encoding truncated ncsrs2 (ncsrs2t) lacking an n-terminal signal peptide and c-terminal hydrophobic regions was expressed in escherichia coli, and its diagnostic potential in an enzyme-linked immunosorbent assay (elisa) was evaluated. elisa could discriminate clearly between known n. caninum-positive and -negative sera from cattle. field serum samples collecte ...200515856900
development of neospora caninum cultured with human serum in vitro and in vivo.because there has been no report of symptomatic neospora caninum infection in humans, we examined the effect of human serum on the parasite's growth in either a bovine angioendothelial cell or caco-2 cell culture in vitro and in immunocompromised mice in vivo. there was no difference in intracellular parasite numbers between cells incubated with human serum at 24 hr after challenge and those incubated with fetal bovine serum (fbs), which has no titer for the anti-n. caninum agglutination antibod ...200515856911
serological survey of selected pathogens of free-ranging foxes in southern argentina, 1998--2001.a serological survey was conducted in the patagonia region of argentina to estimate the prevalence of nine disease agents within the populations of free-ranging culpeo (dusicyon culpaeus) and grey (dusicyon griseus) foxes. the disease agents were aujeszky's disease virus (adv), brucella, canine adenovirus (cav), canine distemper virus (cdv), canine parvovirus (cpv), encephalitozoon cuniculi, leptospira, neospora caninum, and toxoplasma gondii. a total of 84 foxes were sampled (28 culpeo and 56 g ...200415861875
cutaneous manifestations of disseminated toxoplasmosis in an immunosuppressed dog.a 3.5-year-old, castrated male, giant schnauzer was presented with alopecic pustular dermatitis. immune-mediated hemolytic anemia had been diagnosed 45 days previously. at the time of presentation, the dog was receiving prednisone, azathioprine, and cyclosporine. cutaneous protozoosis was diagnosed, and postmortem examination revealed protozoa within cutaneous, cardiac, pancreatic, and pulmonary tissues. the protozoa divided by endodyogeny, had the morphology of toxoplasma gondii (t. gondii) tac ...200515870255
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