| equine protozoal myelitis in panamanian horses and isolation of sarcocystis neurona. | schizonts of sarcocystis neurona were identified microscopically in hematoxylin-eosin-stained spinal cord sections from 2 native panamanian horses that exhibited clinical signs of equine protozoal myelitis (epm). spinal cord homogenate from a third panamanian horse with epm was inoculated onto monolayers of cultured bovine monocytes (m617). intracytoplasmic schizonts containing merozoites arranged in rosette forms surrounding a central residual body first were observed 13 wk postinoculation. par ... | 1992 | 1403437 |
| sarcocystis neurona-associated ataxia in horses in brazil. | sarcocystis neurona-like schizonts were found in sections of brain and spinal cord of two ataxic horses from brazil. the diagnosis was supported by staining with anti-sarcocystis serum in an immunohistochemical test. one of the affected horses was born in argentina and raised in brazil, and the other horse was born and raised in brazil. | 1992 | 1466140 |
| a five year (1985-1989) retrospective study of equine neurological diseases with special reference to rabies. | a retrospective study of horses necropsied between 1985 and 1989 at a diagnostic laboratory of a veterinary school in north america is documented. in this investigation over 20 per cent of the horses had clinical neurological signs. equine protozoal myeloencephalitis (caused by sarcocystis neurona) and cervical stenotic myelopathy (wobbler syndrome) were the most common of these disorders. the veterinary school is located in the midst of a raccoon rabies enzootic area. however, only four cases o ... | 1992 | 1644935 |
| characterization of sarcocystis neurona from a thoroughbred with equine protozoal myeloencephalitis. | morphological information is presented for syntype material of the etiologic agent of equine protozoal myeloencephalitis, sarcocystis neurona. a clinical description of the horse from which the organism was isolated and the methodology used to immunosuppress the horse in an attempt to increase parasite numbers are also given. the description includes microscopic details observed both with light and transmission electron microscopy. mainly stages from tissue are illustrated, but information is al ... | 1992 | 1740059 |
| sarcocystis neurona n. sp. (protozoa: apicomplexa), the etiologic agent of equine protozoal myeloencephalitis. | sarcocystis neuronan n. sp. is proposed for the apicomplexan taxon associated with myeloencephalitis in horses. only asexual stages of this parasite presently are known, and they are found within neuronal cells and leukocytes of the brain and spinal cord. the parasite is located in the host cell cytoplasm, does not have a parasitophorous vacuole, and divides by endopolygeny. schizonts are 5-35 microns x 5-20 microns and contain 4-40 merozoites arranged in a rosette around a prominent residual bo ... | 1991 | 1901359 |
| sarcocystis neurona cultured in vitro from a horse with equine protozoal myelitis. | | 1991 | 1915236 |
| in vitro cultivation of sarcocystis neurona from the spinal cord of a horse with equine protozoal myelitis. | asexual stages of sarcocystis neurona were seen in cultured bovine monocytes (m617) inoculated with tissue homogenates from the spinal cord of a horse with naturally acquired protozoal myelitis. organisms first were observed as intracytoplasmic schizonts and later as motile extracellular zoites capable of infecting surrounding m617 cells. parasites most often occurred as clusters of merozoites dispersed throughout the host cell cytoplasm; however, schizonts also contained merozoites arranged in ... | 1991 | 1919932 |
| phylogenetic relationship of sarcocystis neurona to other members of the family sarcocystidae based on small subunit ribosomal rna gene sequence. | sarcocystis neurona is a coccidial parasite that causes a neurologic disease of horses in north and south america. the natural host species are not known and classification is based on ultrastructural analysis. the small subunit ribosomal rna (ssurna) gene of s. neurona was amplified using polymerase chain reaction techniques and sequenced by sanger sequencing reactions. the sequence was compared with partial sequences of s. muris, s. gigantea, s. tenella, s. cruzi, s. arieticanis, s. capracanis ... | 1994 | 7799170 |
| differentiation of sarcocystis neurona from eight related coccidia by random amplified polymorphic dna assay. | four isolates of sarcocystis neurona from horses with equine protozoal myeloencephalitis and eight species of coccidia from the genera sarcocystis, toxoplasma or eimeria were differentiated using the random amplified polymorphic dna assay. a single, common, 550-bp dna fragment was amplified from the dna of each s. neurona isolate using a 16-nucleotide primer. crosshybridization analyses among s. neurona isolates showed that dna fragments had at least partial sequence homology. the primer generat ... | 1994 | 7877630 |
| encephalomyelitis due to a sarcocystis neurona-like protozoan in a rhesus monkey (macaca mulatta) infected with simian immunodeficiency virus. | a captive-born rhesus monkey (macaca mulatta) experimentally infected with simian immunodeficiency virus developed neurologic abnormalities approximately seven months postinoculation. a chronic necrotizing encephalomyelitis with intralesional protozoal schizonts was diagnosed histologically. the protozoa was identified as sarcocystis neurona based on its morphologic characteristics by light and electron microscopic examination, the developmental stages of the schizonts, and positive staining wit ... | 1994 | 7943553 |
| immunohistochemical study to demonstrate sarcocystis neurona in equine protozoal myeloencephalitis. | a 5-year (1985-1989) retrospective immunohistochemical study was conducted using an avidin-biotin complex (abc) immunoperoxidase method to demonstrate sarcocystis neurona in histologically suspect cases of equine protozoal myeloencephalitis (epm). primary antibodies against s. neurona and s. cruzi were utilized for the abc technique. the findings were compared with those from cases in which the organisms were detected by examination of hematoxylin and eosin (he)-stained neuronal sections. he-sta ... | 1993 | 8373858 |
| equine protozoal myeloencephalitis: antigen analysis of cultured sarcocystis neurona merozoites. | antigens of cultured sarcocystis neurona merozoites were examined using immunoblot analysis. blotted proteins were probed with s. cruzi, s. muris, and s. neurona antisera produced in rabbits, s. fayeri (pre- and post-infection) and s. neurona (pre- and post-inoculation) sera produced in horses, immune sera from 7 histologically confirmed cases of equine protozoal myeloencephalitis (epm), and pre-suckle serum from a newborn foal. eight proteins, 70, 24, 23.5, 22.5, 13, 11, 10.5, and 10 kd, were d ... | 1993 | 8466988 |
| identification of opossums (didelphis virginiana) as the putative definitive host of sarcocystis neurona. | sarcocystis neurona is an apicomplexan that causes equine protozoal myeloencephalitis (epm) in north and south america. horses appear to be an aberrant host, because the merozoites continually divide in the central nervous system, without encysting. the natural host species has not previously been identified. the small subunit ribosomal rna (ssurna) gene of s. neurona was compared to those of sarcocystis muris, sarcocystis cruzi, toxoplasma gondii, and cryptosporidium parvum to identify a unique ... | 1995 | 8544064 |
| sarcocystis falcatula from passerine and psittacine birds: synonymy with sarcocystis neurona, agent of equine protozoal myeloencephalitis. | equine protozoal myeloencephalitis (epm) is a neurologic disease of horses caused by sarcocystis neurona. the horse is a dead-end host for s. neurona and the definitive and intermediate hosts have not previously been identified. we hypothesized that s. neurona is actually sarcocystis falcatula, a parasite that cycles in nature between virginia opossums (didelphis virginiana) and any of a variety of avian intermediate hosts. we extracted dna from s. falcatula sarcocysts in the muscle of a brown-h ... | 1995 | 8544067 |
| sequence analysis and polymerase chain reaction amplification of small subunit ribosomal dna from sarcocystis neurona. | to identify sarcocystis neurona-specific dna sequences in the nuclear small subunit ribosomal rna (nss-rrna) gene that could be used to distinguish s neurona from other closely related protozoal parasites, and to evaluate a polymerase chain reaction (pcr) test, using broad based primers and a unique species-specific probe on csf for detection of s neurona in equids. | 1996 | 8807006 |
| neosporosis as a cause of equine protozoal myeloencephalitis. | neosporosis was diagnosed in an 11-year-old quarter horse gelding with clinical signs and diagnostic test results compatible with equine protozoal myeloencephalitis (epm). presumptive postmortem diagnosis of epm attributable to sarcocystis neurona infection is generally made on the basis of detecting an antibody titer to s neurona in the csf or characteristic histologic lesions, even when parasites have not been specifically identified. neosporosis was confirmed in the horse described here by us ... | 1996 | 8944807 |
| serum antibodies to sarcocystis neurona--half the horses in the united states have them! | | 1997 | 9040830 |
| seroprevalence of antibodies to sarcocystis neurona in horses residing in a county of southeastern pennsylvania. | to determine seroprevalence of sarcocystis neurona-specific antibodies in a population of horses residing in chester county, pa. | 1997 | 9040838 |
| seroprevalence of antibodies to sarcocystis neurona in horses residing in ohio. | to determine the seroprevalence of serum antibodies to sarcocystis neurona in horses residing in ohio. | 1997 | 9040839 |
| seroprevalence of antibodies to sarcocystis neurona in horses residing in oregon. | to determine seroprevalence of antibodies to sarcocystis neurona in neurologically normal horses residing in 4 regions of oregon and to describe the effects of age, gender, breed, and housing on seroprevalence within each region. | 1997 | 9040840 |
| experimental induction of equine protozoal myeloencephalitis in horses using sarcocystis sp. sporocysts from the opossum (didelphis virginiana). | sarcocystis sp. sporocysts isolated from eight feral opossums (didelphis virginiana) were pooled and fed to 18 commercially reared budgerigars (melopsittacus undulatus), 14 wild-caught sparrows (passer domesticus), one wild-caught slate-colored junco (junco hyemalis) and five weanling horses (equus caballus). all budgerigars died within 5 weeks post inoculation (wpi). histologic examination revealed meronts within the pulmonary epithelia and typical sarcocystis falcatula sarcocysts developing in ... | 1997 | 9066066 |
| epizootic of equine protozoal myeloencephalitis on a farm. | to determine the clinical findings, course of treatment, and long-term outcome of horses on a farm in central kentucky during an epizootic of equine protozoal myeloencephalitis (epm). | 1997 | 9096721 |
| equine protozoal myeloencephalitis. | equine protozoal myeloencephalitis (epm) is a common neurologic disease of horses in the americas. horses with epm most commonly have abnormalities of gait, but they also may present with signs of brain disease. the disease ranges in severity from mild lameness to sudden recumbency, and clinical signs usually are progressive. a causative agent, sarcocystis neurona, has been isolated from affected horses, and serologic surveys suggest that approximately 50% of horses in the united states have bee ... | 1997 | 9106345 |
| fatal hepatic sarcocystosis in two polar bears (ursus maritimus). | fatal hepatic sarcocystosis was diagnosed in 2 polar bears from a zoo in anchorage, alaska. gross lesions were icterus and systemic petechiae. marked microscopic lesions were detected only in the liver and included severe random necrotizing hepatitis with hemorrhage. only asexual stages of an apicomplexan parasite were detected within hepatocytes, and rare extracellular zoites were seen in foci of necrosis. the parasite divided by endopolygeny, and occasionally merozoites formed rosettes around ... | 1997 | 9194839 |
| micropreparative high resolution purification of proteins by a combination of sodium dodecyl sulfate-polyacrylamide gel electrophoresis, isoelectric focusing, and membrane blotting. | we report a simple, economical, and efficient protocol for protein purification from cells. first, proteins of cell lysates were separated by standard sodium dodecyl sulfate-polyacrylamide gel electrophoresis (sds-page) and electroblotted to protein-blotting membrane. the blots were stained with coomassie blue or developed by immunoblotting to visualize specific proteins. the bands corresponding to those visible by immunoblotting were excised from the dye-stained blots and subjected to isoelectr ... | 1997 | 9234899 |
| pyogranulomatous encephalitis associated with an unidentified sarcocystis neurona-like organism in a horse. | | 1997 | 9249180 |
| examination of extraintestinal tissue cysts of isospora belli. | relapse is common in immunocompetent and immunosuppressed humans infected with isospora belli and is believed to be associated with the presence of extraintestinal stages. in the present study, we examined this important stage in an aids patient using histological, immunohistological, histochemical, and ultrastructural methods to better understand the development and structure of this stage and to develop better means of detecting infections. antisera made in rabbits to isospora suis, toxoplasma ... | 1997 | 9267401 |
| experimental infection of nude mice as a model for sarcocystis neurona-associated encephalitis. | the development of a rodent model for the study of sarcocystis neurona encephalitis is described. animal models have been developed for a number of protozoal parasites; however, no such model exists for s. neurona. the approach used in this study is similar to that employed for other closely related protozoal parasites such as neospora caninum and toxoplasma gondii. a time course of infection was examined, and histopathology, immunohistochemistry, and parasite isolation were used to examine the ... | 1997 | 9272562 |
| in vitro cultivation and experimental inoculation of sarcocystis falcatula and sarcocystis neurona merozoites into budgerigars (melopsittacus undulatus). | this is a report of the isolation and in vitro propagation of merozoites of sarcocystis falcatula. culture-derived s. falcatula merozoites remained infectious after several passages in tissue culture as determined by the susceptibility of experimentally inoculated melopsittacus undulatus that died of pulmonary sarcocystosis after experimental inoculation. there was no obvious clinical disease or lesion when sarcocystis neurona merozoites were used to inoculate m. undulatus. on the basis of the b ... | 1997 | 9406803 |
| evidence that surface proteins sn14 and sn16 of sarcocystis neurona merozoites are involved in infection and immunity. | sarcocystis neurona is the etiologic agent of equine protozoal myeloencephalitis (epm). based on an analysis of 25,000 equine serum and cerebrospinal fluid (csf) samples, including samples from horses with neurologic signs typical of epm or with histologically or parasitologically confirmed epm, four major immunoblot band patterns have been identified. twenty-three serum and csf samples representing each of the four immunoblot patterns were selected from 220 samples from horses with neurologic s ... | 1998 | 9573058 |
| neospora caninum-associated equine protozoal myeloencephalitis. | equine protozoal myeloencephalitis (epm) was clinically diagnosed in a 20-year-old horse with severe ataxia. the cerebrospinal fluid was positive for sarcocystis neurona antibodies by western blot. the horse was administered corticosteroids to facilitate in vitro culture of s. neurona from its spinal cord following necropsy. microscopic lesions of epm were present in the brain and in the spinal cord, including multifocal inflammatory cellular infiltrates and several large groups of protozoa. imm ... | 1998 | 9831950 |
| isolation of a third species of sarcocystis in immunodeficient mice fed feces from opossums (didelphis virginiana) and its differentiation from sarcocystis falcatula and sarcocystis neurona. | opossums (didelphis virginiana) were found to be hosts for 3 species of sarcocystis: sarcocystis falcatula with an avian intermediate host, s. neurona with an undetermined intermediate host, and a third, unnamed, species. sporocysts from the intestines of 2 opossums (nos. 26 and 47) were fed to budgerigars (melopsittacus undulatus), nude mice, and gamma-interferon knockout (ko) mice. sporocysts of s. falcatula were not infective to nude or ko mice. sporocysts of s. neurona induced encephalitis i ... | 1998 | 9920306 |
| meningoencephalitis due to a sarcocystis neurona-like protozoan in pacific harbor seals (phoca vitulina richardsi). | seven pacific harbor seals with meningoencephalitis associated with sarcocystis neurona-like protozoa are described. six of the 7 seals were free-ranging and were found stranded over an 80-km stretch of central california coastline; the other was captive. all had marked to severe nonsuppurative meningoencephalitis, most severe in the cerebellar cortex. immunohistochemistry for s. neurona antigens was positive on brain tissue in all cases, revealing numerous merozoites as well as developing and m ... | 1998 | 9920311 |
| isolation in immunodeficient mice of sarcocystis neurona from opossum (didelphis virginiana) faeces, and its differentiation from sarcocystis falcatula. | sarcocystis neurona was isolated in nude mice and gamma-interferon knockout mice fed sporocysts from faeces of naturally infected opossums (didelphis virginiana). mice fed sporocysts became lethargic and developed encephalitis. protozoa were first found in the brain starting 21 days post-inoculation. sarcocystis neurona was recovered in cell culture from the homogenate of liver, spleen and brain of a nude mouse 11 days after feeding sporocysts. the protozoa in mouse brain and in cell culture mul ... | 1998 | 9925260 |
| development of sarcocystis falcatula in cell cultures demonstrates that it is different from sarcocystis neurona. | the development of sarcocystis falcatula merozoites in bovine turbinate (bt) cell cultures is described and compared with development of sarcocystis neurona merozoites. merozoites of s. falcatula entered bt cell cultures and increased in size until 3 days post-inoculation when the nucleus of some merozoites developed lobes. developing schizonts present at 4 days contained a lobed nucleus or appeared multinucleate. a single mature schizont was observed 4 days p.i. schizonts were numerous 5 and 6 ... | 1999 | 10205798 |
| multiple dna markers differentiate sarcocystis neurona and sarcocystis falcatula. | studies designed to investigate the causative agent of equine protozoal myeloencephalitis and its life cycle have been hampered by the marked similarity of sarcocystis neurona to other sarcocystis spp. present in the same definitive host. random-amplified polymorphic dna techniques were used to amplify dna from isolates of s. neurona and sarcocystis falcatula. dna sequence analysis of polymerase chain reaction (pcr) products was then used to design pcr primers to amplify specific sarcocystis spp ... | 1999 | 10219299 |
| are sarcocystis neurona and sarcocystis falcatula synonymous? a horse infection challenge. | equine protozoal myeloencephalitis (epm) is a debilitating neurologic disease of the horse. the causative agent. sarcocystis neurona, has been suggested to be synonymous with sarcocystis falcatula, implying a role for birds as intermediate hosts. to test this hypothesis, opossums (didelphis virginiana) were fed muscles containing s. falcatula sarcocysts from naturally infected brown-headed cowbirds (molothrus ater). ten horses were tested extensively to ensure no previous exposure to s. neurona ... | 1999 | 10219313 |
| determination of the activity of pyrimethamine, trimethoprim, sulfonamides, and combinations of pyrimethamine and sulfonamides against sarcocystis neurona in cell cultures. | equine protozoal myeloencephalitis (epm) is a neurologic syndrome in horses from the americas and is usually caused by infection with the apicomplexan parasite, sarcocystis neurona. the activities of pyrimethamine, trimethoprim, sulfachloropyridazine, sulfadiazine, sulfadimethoxine, sulfamethoxazole, sulfamethazine, and sulfathiazole were examined against developing s. neurona merozoites in bovine turbinate cell cultures. a microtiter plate host cell lesion based assay was used to determine the ... | 1999 | 10348099 |
| effects of blood contamination of cerebrospinal fluid on western blot analysis for detection of antibodies against sarcocystis neurona and on albumin quotient and immunoglobulin g index in horses. | to determine effects of blood contamination on western blot (wb) analysis of csf samples for detection of anti-sarcocystis neurona antibodies, and on csf albumin and igg concentrations, albumin quotient (aq), and igg index in horses. | 1999 | 10397068 |
| comparison of the internal transcribed spacer, its-1, from sarcocystis falcatula isolates and sarcocystis neurona. | the genetic diversity among 6 sarcocystis falcatula isolates derived from geographically distinct regions in the u.s.a. was detected using the first internal transcribed spacer region 1 (its-1) of the rrna gene. these sequences were then compared to the full sequence from a sarcocystis neurona isolate obtained from a california horse diagnosed with equine protozoal myeloencephalitis. no nucleotide differences were detected over partial sequence analysis of 2 additional s. neurona isolates: howev ... | 1999 | 10461964 |
| prevalence of antibodies to sarcocystis neurona, toxoplasma gondii and neospora caninum in horses from argentina. | sera from 76 horses from argentina were examined for antibodies to sarcocystis neurona, toxoplasma gondii and neospora caninum. antibodies to s. neurona were found in 27 (35.5%) of 76 horses using immunoblots with culture derived merozoites as antigen. antibodies to t. gondii were found in 10 (13.1%) of 76 horses by using the modified agglutination test with formalin-fixed tachyzoites and mercaptoethanol; titers were 1:25 (two horses), 1:50 (six horses), 1:100 (two horses), and 1:200 (one horse) ... | 1999 | 10489203 |
| serologic prevalence of sarcocystis neurona, toxoplasma gondii, and neospora caninum in horses in brazil. | to determine serologic prevalence of sarcocystis neurona, toxoplasma gondii, and neospora caninum in horses in brazil. | 1999 | 10511862 |
| characterization of a sarcocystis neurona isolate (sn6) from a naturally infected horse from oregon. | an isolate of sarcocystis neurona (sn6) was obtained from the spinal cord of a horse from oregon with neurologic signs. the parasite was isolated in cultures of bovine monocytes and equine spleen cells. the parasite divided by endopolygeny and completed at least one asexual cycle in cell cultures in three days. two gamma interferon knockout mice inoculated with cell culture-derived merozoites became ill 35 d later and s. neurona schizonts and merozoites were found in encephalitic lesions. the pa ... | 1999 | 10519218 |
| sarcocystis speeri n. sp. (protozoa: sarcocystidae) from the opossum (didelphis virginiana). | the north american opossum (didelphis virginiana) is host to at least 3 species of sarcocystis: sarcocystisfalcatula, sarcocystis neurona, and a recently recognized sarcocystis sp. a new name, sarcocystis speeri, is proposed for the third unnamed sarcocystis. immunodeficient mice are an experimental intermediate host for s. speeri. sarcocystis speeri sporocysts are 12-15 x 8-10 microm in size, and its schizonts are found in many organs of mice. sarcocysts of s. speeri are found in skeletal muscl ... | 1999 | 10577729 |
| hepatic sarcocystosis in a horse. | hepatic sarcocystosis was diagnosed in a horse in association with refractory bacterial osteomyelitis and plasma cell tumor of the maxilla and hepatic salmonellosis. gross lesions included pleural, pericardial, and peritoneal effusions, hepatomegaly, gastric ulceration, colonic edema, and proliferative tissues filling 2 maxillary dental alveoli. histologically, liver was characterized by severe suppurative, necrotizing, periportal hepatitis, and severe periacinar necrosis. hepatocytes frequently ... | 1999 | 10577737 |
| simplified technique for isolation, excystation, and culture of sarcocystis species from opossums. | sarcocystis neurona is a protozoan parasite that causes a neurological disease in horses called equine protozoal myeloencephalitis. the route of transmission is speculated to be by fecal-oral transfer of sporocysts shed from opossums. controversy exists regarding both the natural life cycle for this parasite as well as the species identity of opossum sarcocystis. to provide stage-specific material for species comparison, 27 opossums from southern michigan were screened for sarcocystis spp. sporo ... | 1999 | 10577742 |
| prevalence of antibodies to neospora sp. in horses from alabama and characterisation of an isolate recovered from a naturally infected horse [corrected]. | an ifat was used to determine the prevalence of neospora-specific igg antibodies in serum from alabama horses. serum samples (n = 536) were from asymptomatic horses routinely submitted for equine infectious anaemia virus infection testing. we also subjected a 13-year-old horse with cns disease to necropsy examination for isolation and in vitro cultivation of protozoal organisms. in antemortem tests, this horse was positive for antibodies to neospora sp. in the ifat and western immunoblot. result ... | 1999 | 10608440 |
| diclazuril in the horse: its identification and detection and preliminary pharmacokinetics. | diclazuril (4-chlorophenyl [2,6-dichloro-4-(4,5-dihydro-3h-3,5-dioxo-1,2,4-triazin-2-yl)pheny l] acetonitrile), is a benzeneacetonitrile antiprotozoal agent (janssen research compound r 64433) marketed as clinacox . diclazuril may have clinical application in the treatment of equine protozoal myeloencephalitis (epm). to evaluate its bioavailability and preliminary pharmacokinetics in the horse we developed a sensitive quantitative high-pressure liquid chromatography (hplc) method for diclazuril ... | 1999 | 10651466 |
| thoughts on the transmission of sarcocystis neurona. | | 2000 | 10668526 |
| improvement of western blot test specificity for detecting equine serum antibodies to sarcocystis neurona. | equine protozoal myeloencephalitis (epm) is a neurological disease of horses and ponies caused by the apicomplexan protozoan parasite sarcocystis neurona. the purposes of this study were to develop the most stringent criteria possible for a positive test result, to estimate the sensitivity and specificity of the epm western blot antibody test, and to assess the ability of bovine antibodies to sarcocystis cruzi to act as a blocking agent to minimize false-positive results in the western blot test ... | 2000 | 10690772 |
| comparative development and merozoite production of two isolates of sarcocystis neurona and sarcocystis falcatula in cultured cells. | the development and merozoite production of sarcocystis falcatula and 2 isolates (sn6 and sn2) of sarcocystis neurona were studied in various cultured cell lines inoculated with culture-derived merozoites. all 3 parasites underwent multiple cycles of schizogony in vero cells, bovine monocytes (m617 cells), and bovine pulmonary artery endothelial cells (cpa). sarcocystis neurona strains sn6 and sn2 formed schizonts in rat myoblasts (l6) but not in quail myoblasts (qm7); s. falcatula formed schizo ... | 2000 | 10701559 |
| determination of the activity of diclazuril against sarcocystis neurona and sarcocystis falcatula in cell cultures. | diclazuril is a benzeneacetonitril anticoccidial that has excellent activity against the extraintestinal stages of toxoplasma gondii and neospora caninum. it also is highly active against intestinal coccidia of poultry. the present study examined the efficacy of diclazuril in inhibiting merozoite production of sarcocystis neurona and sarcocystis falcatula in bovine turbinate cell cultures. diclazuril inhibited merozoite production by more than 80% in cultures of s. neurona or s. falcatula treate ... | 2000 | 10701584 |
| biological characterisation of sarcocystis neurona isolated from a southern sea otter (enhydra lutris nereis). | sarcocystis neurona was isolated from the brain of a juvenile, male southern sea otter (enhydra lutris nereis) suffering from cns disease. schizonts and merozoites in tissue sections of the otter's brain reacted with anti-s. neurona antiserum immunohistochemically. development in cell culture was by endopolyogeny and mature schizonts were first observed at 3 days postinoculation. pcr of merozoite dna using primer pairs jnb33/jnb54 and restriction enzyme digestion of the 1100 bp product with dra ... | 2000 | 10779575 |
| experimental transmission of sarcocystis speeri dubey and lindsay, 1999 from the south american opossum (didelphis albiventris) to the north american opossum (didelphis virginiana). | sarcocystis speeri dubey and lindsay, 1999 from the south american opossum didelphis albiventris was successfully transmitted to the north american opossum didelphis virginiana. sporocysts from a naturally infected d. albiventris from argentina were fed to 2 gamma-interferon knockout (ko) mice. the mice were killed 64 and 71 days after sporocyst feeding (daf). muscles containing sarcocysts from the ko mouse killed 71 daf were fed to a captive d. virginiana; this opossum shed sporocysts 11 days a ... | 2000 | 10864267 |
| detection of sarcocystis neurona in the brain of a grant's zebra (equus burchelli bohmi). | an 8-yr-old intact male grant's zebra (equus burchelli bohmi) was referred to the veterinary medical teaching hospital of the university of california-davis after being found in the owner's pasture obtunded and in lateral recumbency. the animal was hypothermic, weak, and unwilling to rise. there was no evidence of trauma, and the zebra had seemed normal the preceding evening. there was no extensor rigidity, and cranial nerve reflexes were normal. flexor and extensor reflexes were weak upon initi ... | 2000 | 10884130 |
| inoculation of sarcocystis neurona merozoites into the central nervous system of horses. | equine protozoal myeloencephalitis (epm) is a neurologic syndrome in horses from the americas and is usually caused by infection with the apicomplexan parasite, sarcocystis neurona. a horse model of epm is needed to test the efficacy of chemotherapeutic agents and potential vaccines. five horses that were negative for antibodies to s. neurona in their serum and cerebrospinal fluid (csf) were injected in the subarachnoid space with living merozoites of the sn2 isolate of s. neurona. none of the h ... | 2000 | 10946139 |
| determination of the activity of ponazuril against sarcocystis neurona in cell cultures. | the present study examined the efficacy of ponazuril in inhibiting merozoite production of sarcocystis neurona in cell cultures. ponazuril inhibited merozoite production by more that 90% in cultures of s. neurona treated with 1.0 microg/ml ponazuril and greater than 95% inhibition of merozoite production was observed when infected cultures were treated with 5.0 microg/ml ponazuril. ponazuril may have promise as a therapeutic agent in the treatment of s. neurona induced equine protozoal myeloence ... | 2000 | 10946140 |
| in vitro cultivation of schizonts of sarcocystis speeri dubey and lindsay, 1999. | schizonts of sarcocystis speeri dubey and lindsay, 1999 were cultured in vitro in bovine monocyte and equine kidney cell cultures inoculated with infected tissues of nude and gamma-interferon knockout mice fed sporocysts from opossums, didelphis albiventris. at least 1 asexual cycle was completed in 3 days. in vitro-grown merozoites were structurally and antigenically distinct from those of sarcocystis neurona and sarcocystis falcatula. culture-derived merozoites of s. speeri were not infective ... | 2000 | 10958438 |
| analysis of risk factors for the development of equine protozoal myeloencephalitis in horses. | to investigate risk factors for development of equine protozoal myeloencephalitis (epm) in horses. | 2000 | 11043688 |
| evaluation of risk factors associated with clinical improvement and survival of horses with equine protozoal myeloencephalitis. | to investigate risk factors for use in predicting clinical improvement and survival of horses with equine protozoal myeloencephalitis (epm). | 2000 | 11043689 |
| immunohistochemical confirmation of sarcocystis neurona infections in raccoons, mink, cat, skunk, and pony. | in the central nervous system of 2 raccoons, 1 cat, 1 pony, 2 mink, and 1 skunk, protozoa previously thought to be sarcocystis-like reacted positively to sarcocystis neurona-specific antibodies in an immunohistochemical test. in addition, s. neurona was identified in the brain of another skunk. these observations indicate that s. neurona is not confined to opossums and horses. | 2000 | 11128499 |
| diclazuril preventive therapy of gamma interferon knockout mice fed sarcocystis neurona sporocysts. | gamma interferon knockout (ko) mice (n=74) were fed a lethal dose of approximately 1000 sporocysts of the sn15-op isolate of sarcocystis neurona. groups of mice were given pelleted rodent feed containing 50ppm of diclazuril at different times before and after feeding sporocysts. all mice were examined at necropsy and their tissues were examined immunohistochemically for s. neurona infection. twenty mice were fed sporocysts and given diclazuril starting 5 days before feeding sporocysts and contin ... | 2001 | 11137273 |
| the seroprevalence of antibodies to sarcocystis neurona in michigan equids. | a cross-sectional study of serum antibodies to sarcocystis neurona (the etiologic agent of equine protozoal myeloencephalitis, epm) was performed on michigan equids. our objectives were to determine the seroprevalence of antibodies to s. neurona in michigan equids and to identify specific risk factors for seropositivity. a random, weighted sample of michigan horse farms (stratified by the state's opossum (didelphis virginiana) population and the number of equids on each operation) was selected. ... | 2001 | 11154784 |
| the south american opossum, didelphis marsupialis, from brazil as another definitive host for sarcocystis speeri dubey and lindsay, 1999. | the north american opossum, didelphis virginiana, is a definitive host for at least 3 species of sarcocvstis: s. falcatula stiles 1983, s. neurona dubey, davis, speer, bowman, de lahunta, granstrom, topper, hamir, cummings, suter 1991, and s. speeri dubey and lindsay 1999. in order to identify species of sarcocystis in the south american opossum, d. inarsupialis, sarcocystis sporocysts from the intestines of a naturally infected opossum (d. marsupialis) from brazil were fed to 4 gamma-interferon ... | 2000 | 11155929 |
| completion of the life cycle of sarcocystis neurona. | sarcocystis neurona is the most important cause of a neurologic disease in horses, equine protozoal myeloencephalitis (epm). the complete life cycle of s. neurona, including the description of sarcocysts and intermediate hosts, has not been completed until now. opossums (didelphis spp.) are definitive hosts, and horses and other mammals are aberrant hosts. in the present study, laboratory-raised domestic cats (felis domesticus) were fed sporocysts from the intestine of a naturally infected oposs ... | 2000 | 11191904 |
| a review of sarcocystis neurona and equine protozoal myeloencephalitis (epm). | equine protozoal myeloencephalitis (epm) is a serious neurological disease of horses in the americas. the protozoan most commonly associated with epm is sarcocystis neurona. the complete life cycle of s. neurona is unknown, including its natural intermediate host that harbors its sarcocyst. opossums (didelphis virginiana, didelphis albiventris) are its definitive hosts. horses are considered its aberrant hosts because only schizonts and merozoites (no sarcocysts) are found in horses. epm-like di ... | 2001 | 11223193 |
| characterization of a sarcocystis neurona isolate from a missouri horse with equine protozoal myeloencephalitis. | little information is available about antigenic variation of sarcocystis neurona isolated from horses with equine protozoal myeloencephalitis, nor is there much information available on the specific antibody pattern to s. neurona antigens of horses from different geographic regions where s. neurona isolates have been obtained. this communication reports on the characterization of a new s. neurona isolate, sn-mu1. the isolate was obtained from a 3-year old thoroughbred that had asymmetrical neuro ... | 2001 | 11223195 |
| characteristics of a recent isolate of sarcocystis neurona (sn7) from a horse and loss of pathogenicity of isolates sn6 and sn7 by passages in cell culture. | an isolate of sarcocystis neurona (sn7) was obtained from the spinal cord of a horse with neurologic signs. the parasite was isolated in cultures of bovine monocytes and equine spleen cells. the organism divided by endopolygeny and completed at least one asexual cycle in cell cultures in 3 days. the parasite was maintained by subpassages in bovine monocytes for 10 months when it was found to be non-pathogenic to gamma interferon knockout (ko) mice. revival of a low passage (10th passage) of the ... | 2001 | 11223196 |
| comparison of sarcocystis neurona isolates derived from horse neural tissue. | sarcocystis neurona is a protozoan parasite that can cause neurological deficits in infected horses. the route of transmission is by fecal-oral transfer of sporocysts from opossums. however, the species identity and the lifecycle are not completely known. in this study, sarcocystis merozoites from eight isolates obtained from michigan horses were compared to s. neurona from a california horse (ucd1), sarcocystis from a grackle (cornell), and five sarcocystis isolates from feral opossums from mic ... | 2001 | 11223197 |
| direct agglutination test for the detection of antibodies to sarcocystis neurona in experimentally infected animals. | equine protozoal myeloencephalitis (epm) is a serious neurological disease of horses in the americas. the apicomplexan protozoan most commonly associated with epm is sarcocystis neurona. a direct agglutination test (sat) was developed to detect antibodies to s. neurona in experimentally infected animals. merozoites of the sn6 strain of s. neurona collected from cell culture were used as antigen and 2-mercaptoethanol was added to the antigen suspension to destroy igm antibodies when mixed with te ... | 2001 | 11223198 |
| interpretation of the detection of sarcocystis neurona antibodies in the serum of young horses. | horses that are exposed to sarcocystis neurona, a causative agent of equine protozoal myeloencephalitis, produce antibodies that are detectable in serum by western blot (wb). a positive test is indicative of exposure to the organism. positive tests in young horses can be complicated by the presence of maternal antibodies. passive transfer of maternal antibodies to s. neurona from seropositive mares to their foals was evaluated. foals were sampled at birth (presuckle), at 24h of age (postsuckle), ... | 2001 | 11223199 |
| immunoconversion against sarcocystis neurona in normal and dexamethasone-treated horses challenged with s. neurona sporocysts. | equine protozoal myeloencephalitis is a common neurologic disease of horses in the americas usually caused by sarcocystis neurona. to date, the disease has not been induced in horses using characterized sporocysts from didelphis virginiana, the definitive host. s. neurona sporocysts from 15 naturally infected opossums were fed to horses seronegative for antibodies against s. neurona. eight horses were given 5x10(5) sporocysts daily for 7 days. horses were examined for abnormal clinical signs, an ... | 2001 | 11223200 |
| utilization of stress in the development of an equine model for equine protozoal myeloencephalitis. | neurologic disease in horses caused by sarcocystis neurona is difficult to diagnose, treat, or prevent, due to the lack of knowledge about the pathogenesis of the disease. this in turn is confounded by the lack of a reliable equine model of equine protozoal myeloencephalitis (epm). epidemiologic studies have implicated stress as a risk factor for this disease, thus, the role of transport stress was evaluated for incorporation into an equine model for epm. sporocysts from feral opossums were bioa ... | 2001 | 11223201 |
| initiation of a sarcocystis neurona expressed sequence tag (est) sequencing project: a preliminary report. | to accelerate genetic and molecular characterization of sarcocystis neurona, the primary causative agent of equine protozoal myeloencephalitis (epm), a sequencing project has been initiated that will generate approximately 7000-8000 expressed sequence tags (ests) from this apicomplexan parasite. poly(a)(+) rna was isolated from culture-derived s. neurona merozoites, and a cdna library was constructed in a unidirectional lambda phage cloning vector. sixty phage clones were randomly picked from th ... | 2001 | 11223203 |
| in vitro quantitative analysis of (3)h-uracil incorporation by sarcocytis neurona to determine efficacy of anti-protozoal agents. | parasite-specific incorporation of (3)h-uracil was used to assess the replication of sarcocystis neurona, a protozoal parasite associated with equine protozoal myeloencephalitis (epm). anti-protozoal drugs, pyrimethamine (0.01, 0.1 and 1.0microg/ml pyr), sulfadiazine (5microg/ml; sdz), sulfamethoxazole (5microg/ml; smz), diclazuril (100ng/ml; dcz), atovaquone (0.04ng/ml; atq), tetracycline (5microg/ml; tet) and the herbicide glyphosate (1.5 and 4.5mm; gly) were studied with varying s. neurona pa ... | 2001 | 11223204 |
| in vitro culture and synchronous release of sarcocystis neurona merozoites from host cells. | the growth of sarcocystis neurona, isolate ucd1, in continuous culture was examined in 10 cell lines to identify growth conditions and methods for the preparation of parasites free of gross host cell contamination for molecular studies. the unpredictable, slow release of merozoites in most cell lines prompted development of a method to synchronously release the parasites from infected host cells. the calcium ionophore a23187 at a concentration of 1 microm was found to release intracellular meroz ... | 2001 | 11223205 |
| ultrastructure of schizonts and merozoites of sarcocystis neurona. | the ultrastructure of sarcocystis neurona schizonts and merozoites was studied in specimens derived from cell culture and from the brains of infected mice. schizonts and merozoites were located in the host cell cytoplasm without a parasitophorous vacuole at any stage of development. merozoites divided by endopolygeny. fully formed merozoites had a pellicle, numerous polysomes and ribosomes, smooth and rough endoplasmic reticulum, 22 subpellicular microtubules, 9-16 dense granules, 25-75 micronem ... | 2001 | 11223206 |
| prevalence of neospora hughesi and sarcocystis neurona antibodies in horses from various geographical locations. | parasite-specific antibody responses to neospora antigens were detected using the immunofluorescent antibody test (ifat) and immunoblot analysis in select equine populations. for comparison, a naturally infected neospora hughesi horse and an experimentally inoculated neospora caninum horse were used. in addition, all samples were tested for antibodies to sarcocystis neurona by immunoblot analysis. a total of 208 samples was evaluated. the equine populations were derived from five distinct geogra ... | 2001 | 11223207 |
| prevalence of sarcocystis neurona sporocysts in opossums (didelphis virginiana) from rural mississippi. | sarcocystis species sporocysts were found in intestinal scrapings from 24 of 72 opossums (didelphis virginiana) from rural mississippi. the number of sporocysts in each opossum varied from a few ( < 100000) to 187 million. sporocysts from 24 opossums were bioassayed for sarcocystis neurona infections by feeding to gamma-interferon knockout (ko) mice. s. neurona was detected in the brains of ko mice fed sporocysts from 19 opossums by immunohistochemical staining with anti-s. neurona specific poly ... | 2001 | 11223208 |
| first isolation of sarcocystis neurona from the south american opossum, didelphis albiventris, from brazil. | sarcocystis neurona was isolated from sporocysts from two of eight south american opossums, didelphis albiventris, from brazil. interferon gamma gene knock out (ko) mice fed sporocysts from two opossums developed neurologic sarcocystosis. s. neurona was demonstrated in the brains of infected ko mice by immunohistochemical staining with anti-s. neurona antibody. the parasite was cultivated in cell culture and s. neurona dna was isolated from cultured merozoites. this is the first report of isolat ... | 2001 | 11223209 |
| sporocyst size of isolates of sarcocystis shed by the virginia opossum (didelphis virginiana). | the virginia opossum (didelphis virginiana) is a definitive host for multiple sarcocystis species including sarcocystis neurona, one of the causative agents of equine protozoal myeloencephalitis (epm), a severe, neuromuscular disease of horses. size and morphologic characteristics of isolates of sarcocystis shed by the opossum were examined to determine if differences were useful in discriminating between the isolates and/or species. collections of sporocysts from 17 opossums were molecularly ch ... | 2001 | 11223210 |
| myocarditis and encephalitis associated with sarcocystis neurona infection in raccoons (procyon lotor). | sarcocystis neurona associated granulomatous encephalitis was found in 2 of 84 adult raccoons. both raccoons also had an extensive nonsuppurative myocarditis and one had s. neurona schizonts and merozoites in the myocardium. only the asexual stages (schizonts and merozoites) of s. neurona are found in tissues of naturally infected animals (horse, mink, raccoons, cats, skunk, pony, seals, sea otters) and since these have not been reported outside the central nervous system, the presence of concur ... | 2001 | 11223214 |
| migration and development of sarcocystis neurona in tissues of interferon gamma knockout mice fed sporocysts from a naturally infected opossum. | migration and development of sarcocystis neurona was studied in 50 gamma interferon knockout mice fed graded doses of s. neurona sporocysts from the intestine of a naturally infected opossum. mice were examined at necropsy 1-62 days after feeding sporocysts (dafs). all tissue sections were reacted with anti-s. neurona-specific polyclonal rabbit serum in an immunohistochemical (ihc) test. between 1 and 3 dafs, organisms were seen mainly in intestines. between 4 and 11 dafs, organisms were seen in ... | 2001 | 11223215 |
| sarcocystis neurona and sarcocystis falcatula: monitoring of schizogony in cell culture using fluorescent nuclear labeling. | the nuclei of merozoites of sarcocystis neurona and sarcocystis falcatula were labeled with the fluorescent marker syto21. it was shown that the marker would label the parasites and that they would retain the marker throughout schizogony. thus, there was sufficient marker in the daughter merozoites to make them easily visible with fluorescence microscopy. this technique will be helpful in studying the developmental biology of these parasites in vitro. | 2001 | 11223216 |
| the nine-banded armadillo (dasypus novemcinctus) is an intermediate host for sarcocystis neurona. | the nine-banded armadillo (dasypus novemcinctus) is an intermediate host of at least three species of sarcocystis, sarcocystis dasypi, sarcocystis diminuta, and an unidentified species; however, life cycles of these species have not been determined. following feeding of armadillo muscles containing sarcocysts to the virginia opossum (didelphis virginiana), the opossums shed sporulated sarcocystis sporocysts in their faeces. mean dimensions for sporocysts were 11.0x7.5 microm and each contained f ... | 2001 | 11306111 |
| multiple origin of the dihomoxenous life cycle in sarcosporidia. | although their ssrrna gene sequences are closely related, the lizard sarcosporidia (apicomplexa, sarcocystidae) sarcocystis lacertae and sarcocystis gallotiae posses heteroxenous and dihomoxenous life cycles, respectively. when aligned with available sarcosporidian ssrrna genes, both species constitute a monophyletic clade that is only distantly related with sarcosporidia that have a viperid snake as their definitive host (sarcocystis sp., sarcocystis atheridis). to test the phyletic status of t ... | 2001 | 11306120 |
| determination of the activity of pyrantel tartrate against sarcocystis neurona in gamma-interferon gene knockout mice. | equine protozoal myeloencephalitis (epm) is the most important protozoal disease of horses in the united states. some horse owners and equine clinicians believe that horses which are on daily pyrantel tartrate at 2.64mg/kg for helminth prophylaxis are less likely to develop epm. the present study examined the efficacy of pyrantel tartrate in preventing clinical disease in gamma-interferon gene knockout (balb/c-ifng(tm1ts)) mice. no activity was seen against sporocyst-induced sarcocystis neurona ... | 2001 | 11358629 |
| dual sarcocystis neurona and toxoplasma gondii infection in a northern sea otter from washington state, usa. | dual sarcocystis neurona and toxoplasma gondii infection was observed in a northern sea otter from washington, usa. the animal was found stranded, convulsed, and died shortly thereafter. encephalitis caused by both s. neurona and t. gondii was demonstrated in histological sections of brain. immunohistochemical examination of sections with s. neurona specific antisera demonstrated developmental stages that divided by endopolygeny and produced numerous merozoites. pcr of brain tissue from the sea ... | 2001 | 11390085 |
| [equine protozoal myeloencephalitis in the netherlands? an overview]. | equine protozoal myeloencephalitis (epm) was diagnosed in a dutch warmblood gelding a few months after its export to the united states. the horse came back and was treated here. additionally, an overview of the disease complex 'epm' is given. mode of infection, diagnosis of disease and its differential diagnoses, and general therapeutic options are presented. although epm due to infection with sarcocystis neurona in europe seems restricted to those horses that return or are imported from north a ... | 2001 | 11392988 |
| isolation and characterization of two parasitic protozoa from a pacific harbor seal (phoca vitulina richardsi) with meningoencephalomyelitis. | two species of protozoans were isolated from a harbor seal with fatal meninogoencephalitis. serologic reactivity was detected to both sarcocystis neurona and toxoplasma gondii. parasites associated with brain inflammation and necrosis reacted only with immunohistochemical stains utilizing polyclonal antisera raised against sarcocystis neurona. however, 2 distinct parasites were observed in cell cultures derived from the seal's brain tissue. these parasites were separated by mouse passage and lim ... | 2001 | 11534647 |
| acute sarcocystis falcatula-like infection in a carmine bee-eater (merops nubicus) and immunohistochemical cross reactivity between sarcocystis falcatula and sarcocystis neurona. | an unidentified sarcocystis falcatula-like infection was diagnosed in a captive bee-eater (merops nubicus) in a zoo in florida. the bird died suddenly, probably due to protozoa-associated pneumonia. protozoal schizonts were found in lungs and heart, and immature sarcocysts were seen in skeletal muscles. ultrastructurally, schizonts were located in capillary endothelium and merozoites lacked rhoptries, consistent with the structure of sarcocystis species. sarcocysts were immature, microscopic, an ... | 2001 | 11534648 |
| suspected protozoal myeloencephalitis in a two-month-old colt. | a two-month-old appaloosa colt developed neurological signs shortly after birth involving deficits affecting cranial nerves iv, vii, viii, ix, x and xii, and possibly nerve vi. the most likely differential diagnoses were congenital anomalies, meningoencephalitides, trauma or nutritional causes. the foal was investigated by the analysis of cerebrospinal fluid (csf), electromyelography (emg), brain auditory evoked responses, magnetic resonance imaging (mri), peripheral nerve biopsy, and western bl ... | 2001 | 11558662 |
| the gamma interferon knockout mouse model for sarcocystis neurona: comparison of infectivity of sporocysts and merozoites and routes of inoculation. | the dose-related infectivity of sarcocystis neurona sporocysts and merozoites of 2 recent isolates of s. neurona was compared in gamma interferon knockout (ko) mice. tenfold dilutions of sporocysts or merozoites were bioassayed in mice, cell culture, or both. all 8 mice, fed 1,000 sporocysts, developed neurological signs with demonstrable s. neurona in their tissues. of 24 mice fed low numbers of sporocysts (100, 10, 1), 18 became ill by 4 wk postinoculation, and s. neurona was demonstrated in t ... | 2001 | 11695388 |
| sarcocystis neurona infections in raccoons (procyon lotor): evidence for natural infection with sarcocysts, transmission of infection to opossums (didelphis virginiana), and experimental induction of neurologic disease in raccoons. | equine protozoal myeloencephalitis (epm) is a serious neurologic disease of horses in the americas and sarcocystis neurona is the most common etiologic agent. the distribution of s. neurona infections follows the geographical distributions of its definitive hosts, opossums (didelphis virginiana, didelphis albiventris). recently, cats and skunks were reported as experimental and armadillos as natural intermediate hosts of s. neurona. in the present report, raccoons (procyon lotor) were identified ... | 2001 | 11698157 |
| prevalence of agglutinating antibodies to sarcocystis neurona in raccoons, procyon lotor, from the united states. | equine protozoal myeloencephalitis (epm) is the most important protozoal disease of horses in north america and it is caused by sarcocystis neurona. natural cases of encephalitis due to s. neurona have been reported in raccoons, procyon lotor. we examined 99 raccoons for agglutinating antibodies to s. neurona using the s. neurona agglutination test (sat) employing formalin-fixed merozoites as antigen. raccoons originated in florida (n=24, collected in 1996), new jersey (n=25, collected in 1993), ... | 2001 | 11698158 |
| neurologic disease in gamma-interferon gene knockout mice caused by sarcocystis neurona sporocysts collected from opossums fed armadillo muscle. | fifteen gamma-interferon gene knockout mice were each orally inoculated with 5 x 10(3) sarcocystis sporocysts derived from virginia opossums (didelphis virginiana) fed nine-banded armadillo (dasypus novemcinctus) muscle containing sarcocysts. three mice were inoculated with similarly obtained homogenates, but in which no sporocysts were detected. mouse m8 was pregnant when inoculated and gave birth during the trial. fifteen of 15 (100%) mice inoculated with sporocysts developed neurologic signs ... | 2002 | 11751001 |
| lymphocyte responses and immunophenotypes in horses with sarcocystis neurona infection. | | 2001 | 11770997 |
| risk factors associated with the presence of sarcocystis neurona sporocysts in opossums (didelphis virginiana). | sarcocystis neurona is the most important cause of equine protozoal myeloencephalitis (epm) in horse in the americas. the only known definitive host for this parasite in the united states is the opossum (didelphis virginiana); however, despite the importance of the disease, the epidemiology of the parasite in the definitive host is poorly understood. to begin addressing these data gaps, potential risk factors were evaluated for their association with the presence of sporocysts of s. neurona in o ... | 2001 | 11777597 |
| mice lacking the gene for inducible or endothelial nitric oxide are resistant to sporocyst induced sarcocystis neurona infections. | equine protozoal myeloencephalitis (epm) is a neurologic syndrome in horses from the americas and is usually caused by infection with the apicomplexan parasite, sarcocystis neurona. little is known about the role of immunobiological mediators to this parasite. nitric oxide (no) is important in resistance to many intracellular parasites. we, therefore, investigated the role of inducible and endothelial no in resistance to clinical disease caused by s. neurona in mice. groups of interferon-gamma g ... | 2002 | 11777610 |
| structure of sarcocystis neurona sarcocysts. | the ultrastructure of sarcocystis neurona sarcocysts was studied from muscle of an experimentally infected cat. the cat was killed 144 days after being fed sporocysts from a naturally infected opossum. sarcocysts were microscopic, up to 700 microm long, and up to 50 microm wide. by light microscopy, the sarcocyst wall was 1-2 microm thick. ultrastructurally, the sarcocyst wall consisted of numerous villar protrusions. the villar protrusions were up to 2.8 microm long and 0.4 microm wide, with a ... | 2001 | 11780816 |