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Antoinette E. Marsh - One of the best experts on this subject based on the ideXlab platform.
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sarcocystis neurona reacting antibodies in missouri feral domestic cats felis domesticus and their role as an intermediate host
Parasitology Research, 2002Co-Authors: H O Turay, Bradd C Barr, A Caldwell, K R Branson, M K R Cockrell, Antoinette E. MarshAbstract:Sarcocystis neurona is the Parasite associated with equine protozoal myeloencephalitis (EPM). Recently, cats (Felis domesticus) have been implicated as a potential intermediate host in the life cycle of S. neurona. This study was initiated to determine whether cats have antibodies that react to S. neurona antigens similar to antibodies from horses with EPM, and to evaluate the role of cats as intermediate hosts in the Parasite's life cycle. Nine feral cats were used for analysis. Only one had antibodies reacting to S. neurona antigens. Muscle tissue from this cat, with detectable sarcocysts in the tongue, was fed to an opossum (Didelphis virginiana). The opossum shed sporocysts, which were then fed to gamma-interferon receptor knockout mice. Histopathology, immunohistochemistry, Parasite Isolation and molecular analysis were used to examine the pathology and associated Parasites in the mice. The study suggests that the domestic cat can serve as an intermediate host to S. neurona or a S. neurona-like organsim.
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experimental infection of nude mice as a model for sarcocystis neurona associated encephalitis
Parasitology Research, 1997Co-Authors: Antoinette E. Marsh, Bradd C Barr, Jeffrey Lakritz, Robert W Nordhausen, John E Madigan, Patricia A. ConradAbstract:The development of a rodent model for the study of Sarcocystisneurona 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 Neosporacaninum and Toxoplasmagondii. A time course of infection was examined, and histopathology, immunohistochemistry, and Parasite Isolation were used to examine the pathogenesis and follow the infection from 1 to 6 weeks postinoculation. S.neurona was associated with the development of encephalitis in these mice, and the immune status determined the susceptibility of these mice to S. neurona-associated encephalitis.
Dominique Aubert - One of the best experts on this subject based on the ideXlab platform.
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Toxoplasma gondii in beef consumed in France: regional variation in seroprevalence and Parasite Isolation
Parasite (Paris France), 2019Co-Authors: Radu Blaga, Dominique Aubert, Anne Thébault, Catherine Perret, Régine Geers, Myriam Thomas, Annie Alliot, Vitomir Djokic, Naïma Ortis, Lénaïg HalosAbstract:In France, the consumption of cattle and sheep meat appears to be a risk factor for infection of pregnant women with Toxoplasma gondii. Several nation-wide surveys in France have investigated the prevalence of T. gondii in sheep and pig meat, but little is known at present about the prevalence of the Parasite in beef. The main objective of the present cross-sectional survey was to estimate the seroprevalence of T. gondii infection in beef consumed in France. A secondary objective was to attempt to isolate T. gondii from cattle tissues and to study the geographical and age variations of this seroprevalence. The overall estimate of seroprevalence of T. gondii in bovine carcasses (n = 2912), for a threshold of 1:6 was 17.38%. A strong age effect was observed (p 8 months). Seroprevalence estimates given by area of birth and area of slaughtering for adults showed that the areas with the highest seroprevalence were not the same between these two variables. Only two strains, corresponding to genotype II, were isolated from heart samples, indicating that there is a limited risk of human infection with T. gondii, which needs to be correlated with the food habit of consuming raw or undercook (bleu or saignant) beef. However, new questions have emerged, especially concerning the Isolation of Parasites from beef and the precise role of bovines, generally described as poor hosts for T. gondii, in human infection.
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Toxoplasma strain type and human disease: risk of bias during Parasite Isolation?
Trends in parasitology, 2004Co-Authors: Isabelle Villena, Maggy Marle, Marie-laure Dardé, Jean-michel Pinon, Dominique AubertAbstract:A recent publication has described for the first time the use of restriction analysis directly on biological samples to show the high frequency of multiple Toxoplasma gondii infection in individual patients. However, no mixed infection has been reported in other studies, and no cases have yet been identified either by inoculation of mice or in vitro culture. Here, we discuss the possibility that the Parasite Isolation process could represent a risk of bias in the type determination of the Toxoplasma strain responsible for infection.
Silva, Mônica Cristina De Moraes - One of the best experts on this subject based on the ideXlab platform.
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Estudo epidemiológico da amebíase no Estado do Pará utilizando diferentes metodologias para diagnóstico
2005Co-Authors: Silva, Mônica Cristina De MoraesAbstract:A epidemiologia da amebíase está sendo reavaliada desde que a E. histolytica (patogênica) foi considerada espécie distinta de E. dispar (não patogênica). Neste estudo, investigou-se a freqüência da amebíase em uma amostra de residentes do Pará por diferentes técnicas de diagnóstico e avaliou-se a patogenia do parasito. Os participantes (n = 845) forneceram material fecal e destes, 191 foram entrevistados quanto aos sintomas de diarréia, cólicas intestinais, constipação, náuseas e vômito. Foram também analisados 8 exsudatos de pacientes com suspeita de amebíase hepática. As amostras foram observadas sob microscopia de luz e a confirmação de E. histolytica feita a partir da pesquisa de antígenos. Um total de 98 amostras fecais e todos os exsudatos foram semeados em meio Pavlova para isolamento e posterior caracterização bioquímica e molecular (identificação de espécie e genotipagem). Isolados de outras regiões do Brasil foram também genotipados. A positividade obtida foi de 29,35% (248/845) e não houve correlação com a faixa etária. A microscopia revelou baixa sensibilidade (45,26%; 74/334), porém elevada especificidade (87,03%; 260/334) quando comparada ao ELISA. Houve relação significativa (OR 4,4026) entre a presença de sintomas e a positividade no ELISA, sendo a diarréia (58,82%) e a cólica intestinal (58,82%) os sintomas mais relatados. Nenhum exsudato foi positivo no exame a fresco, porém 7 foram positivos no ELISA. Obteve-se 22 isolados de material fecal e a caracterização da HE foi possível em 13, dos quais 7 E. histolytica e 6 E. dispar. O DNA de 22 isolados e dos exsudatos foram testados para identificação molecular de espécie e genotipagem. Do total, 16 cultivos (9 cepas mistas, 4 E. dispar e 3 E. histolytica) e 5 exsudatos (todos E. histolytica) amplificaram na PCR. A genotipagem identificou adicional positividade para E. histolytica em um exsudato e revelou diferentes polimorfismos de comprimento para o locus 1-2 de E. histolytica e E. dispar do Pará e de outras regiões do Brasil e um caso de co-infecção por diferentes genótipos de E. dispar. Nossos resultados revelam que a amebíase invasiva é um importante problema de saúde pública em nossa população e grande variedade de genótipos de E. histolytica contribuem para a doença no Brasil.ABSTRACT: The amebiasis epidemiology had been evaluated since the E. histolytica (pathogenic) was differentiated from E. dispar (non-pathogenic). In this study, it had investigated the amebiasis frequency in residents from Pará using different diagnostic techniques and evaluated the Parasite pathogenesis. All participants (n = 845) had given their fecal material and from them, 191 were asked about the symptoms of diarrhea, abdomen pain, constipation, nausea and vomit. We had also analyzed 8 liver exudates from patients suspected of hepatic amebiasis. All samples were examined by microscopy and the E. histolytica confirmation was done by antigen detection (E. histolytica Test. TechLab). Of the total, 98 fecal samples and all exudates were cultured in Pavlova medium for Parasite Isolation and biochemical characterization and molecular (species identification and genotyping of the locus 1-2). Strains from other Brazil regions were also genotyped. The positive rate for E. histolytica found was 29.35% (248/845) and there was no correlation with age. The sensitivity of the microscopy method was low (45.26% - 74/334) and the specificity high (87.03% - 260/334) when compared to the ELISA test. The correlation between presence of symptoms and ELISA positive results was significant (OR 4.4026) with the diarrhea and abdominal pain being the most reported. None of the exudate samples was positive under the microscopy, but 7 of them were ELISA positive. We had success in culturing only 22 fecal samples. The characterization of HE was possible only for 13 isolates, from which, 7 were E. histolytica and 6 E. dispar. The DNA of the 22 isolates and all exudates were tested by PCR for the species identification and genotyping. Of the total, 16 strains (9 mixed, 4 E. dispar and 3 E. histolytica) and 5 exudate had amplified at the PCR. The genotyping had identified additional positivity for E. histolytica in one exudate and showed different length polymorphisms for the locus 1-2 de E. histolytica and E. dispar of Pará and other Brazil regions and one case of co-infection by different genotypes of the E. dispar. Our results had showed that the invasive amebiasis is an important public health problem within the Amazonian population and that the high genotype variability of E. histolytica contribute for the maintenance of this disease in Brazil
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Estudo epidemiológico da amebíase no Estado do Pará utilizando diferentes metodologias para diagnóstico
Programa de Pós-Graduação em Biologia de Agentes Infecciosos e Parasitários, 2005Co-Authors: Silva, Mônica Cristina De MoraesAbstract:The amebiasis epidemiology had been evaluated since the E. histolytica (pathogenic) was differentiated from E. dispar (non-pathogenic). In this study, it had investigated the amebiasis frequency in residents from Pará using different diagnostic techniques and evaluated the Parasite pathogenesis. All participants (n = 845) had given their fecal material and from them, 191 were asked about the symptoms of diarrhea, abdomen pain, constipation, nausea and vomit. We had also analyzed 8 liver exudates from patients suspected of hepatic amebiasis. All samples were examined by microscopy and the E. histolytica confirmation was done by antigen detection (E. histolytica Test. TechLab). Of the total, 98 fecal samples and all exudates were cultured in Pavlova medium for Parasite Isolation and biochemical characterization and molecular (species identification and genotyping of the locus 1-2). Strains from other Brazil regions were also genotyped. The positive rate for E. histolytica found was 29.35% (248/845) and there was no correlation with age. The sensitivity of the microscopy method was low (45.26% - 74/334) and the specificity high (87.03% - 260/334) when compared to the ELISA test. The correlation between presence of symptoms and ELISA positive results was significant (OR 4.4026) with the diarrhea and abdominal pain being the most reported. None of the exudate samples was positive under the microscopy, but 7 of them were ELISA positive. We had success in culturing only 22 fecal samples. The characterization of HE was possible only for 13 isolates, from which, 7 were E. histolytica and 6 E. dispar. The DNA of the 22 isolates and all exudates were tested by PCR for the species identification and genotyping. Of the total, 16 strains (9 mixed, 4 E. dispar and 3 E. histolytica) and 5 exudate had amplified at the PCR. The genotyping had identified additional positivity for E. histolytica in one exudate and showed different length polymorphisms for the locus 1-2 de E. histolytica and E. dispar of Pará and other Brazil regions and one case of co-infection by different genotypes of the E. dispar. Our results had showed that the invasive amebiasis is an important public health problem within the Amazonian population and that the high genotype variability of E. histolytica contribute for the maintenance of this disease in Brazil.CESUPA - Centro Universitário do ParáA epidemiologia da amebíase está sendo reavaliada desde que a E. histolytica (patogênica) foi considerada espécie distinta de E. dispar (não patogênica). Neste estudo, investigou-se a freqüência da amebíase em uma amostra de residentes do Pará por diferentes técnicas de diagnóstico e avaliou-se a patogenia do parasito. Os participantes (n = 845) forneceram material fecal e destes, 191 foram entrevistados quanto aos sintomas de diarréia, cólicas intestinais, constipação, náuseas e vômito. Foram também analisados 8 exsudatos de pacientes com suspeita de amebíase hepática. As amostras foram observadas sob microscopia de luz e a confirmação de E. histolytica feita a partir da pesquisa de antígenos. Um total de 98 amostras fecais e todos os exsudatos foram semeados em meio Pavlova para isolamento e posterior caracterização bioquímica e molecular (identificação de espécie e genotipagem). Isolados de outras regiões do Brasil foram também genotipados. A positividade obtida foi de 29,35% (248/845) e não houve correlação com a faixa etária. A microscopia revelou baixa sensibilidade (45,26%; 74/334), porém elevada especificidade (87,03%; 260/334) quando comparada ao ELISA. Houve relação significativa (OR 4,4026) entre a presença de sintomas e a positividade no ELISA, sendo a diarréia (58,82%) e a cólica intestinal (58,82%) os sintomas mais relatados. Nenhum exsudato foi positivo no exame a fresco, porém 7 foram positivos no ELISA. Obteve-se 22 isolados de material fecal e a caracterização da HE foi possível em 13, dos quais 7 E. histolytica e 6 E. dispar. O DNA de 22 isolados e dos exsudatos foram testados para identificação molecular de espécie e genotipagem. Do total, 16 cultivos (9 cepas mistas, 4 E. dispar e 3 E. histolytica) e 5 exsudatos (todos E. histolytica) amplificaram na PCR. A genotipagem identificou adicional positividade para E. histolytica em um exsudato e revelou diferentes polimorfismos de comprimento para o locus 1-2 de E. histolytica e E. dispar do Pará e de outras regiões do Brasil e um caso de co-infecção por diferentes genótipos de E. dispar. Nossos resultados revelam que a amebíase invasiva é um importante problema de saúde pública em nossa população e grande variedade de genótipos de E. histolytica contribuem para a doença no Brasil
Bradd C Barr - One of the best experts on this subject based on the ideXlab platform.
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sarcocystis neurona reacting antibodies in missouri feral domestic cats felis domesticus and their role as an intermediate host
Parasitology Research, 2002Co-Authors: H O Turay, Bradd C Barr, A Caldwell, K R Branson, M K R Cockrell, Antoinette E. MarshAbstract:Sarcocystis neurona is the Parasite associated with equine protozoal myeloencephalitis (EPM). Recently, cats (Felis domesticus) have been implicated as a potential intermediate host in the life cycle of S. neurona. This study was initiated to determine whether cats have antibodies that react to S. neurona antigens similar to antibodies from horses with EPM, and to evaluate the role of cats as intermediate hosts in the Parasite's life cycle. Nine feral cats were used for analysis. Only one had antibodies reacting to S. neurona antigens. Muscle tissue from this cat, with detectable sarcocysts in the tongue, was fed to an opossum (Didelphis virginiana). The opossum shed sporocysts, which were then fed to gamma-interferon receptor knockout mice. Histopathology, immunohistochemistry, Parasite Isolation and molecular analysis were used to examine the pathology and associated Parasites in the mice. The study suggests that the domestic cat can serve as an intermediate host to S. neurona or a S. neurona-like organsim.
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Evaluation of an indirect fluorescent antibody test (IFAT) for demonstration of antibodies to Toxoplasma gondii in the sea otter (Enhydra lutris).
The Journal of parasitology, 2002Co-Authors: Melissa A. Miller, Ian A. Gardner, Andrea E. Packham, Jonna A. K. Mazet, Krista D. Hanni, David A. Jessup, James A. Estes, Ronald J. Jameson, Erin Dodd, Bradd C BarrAbstract:An indirect fluorescent antibody test (IFAT) for detection of Toxoplasma gondii infection was validated using serum from 77 necropsied southern sea otters (Enhydra lutris nereis) whose T. gondii infection status was determined through immunohistochemistry and Parasite Isolation in cell culture. Twenty-eight otters (36%) were positive for T. gondii by immunohistochemistry or Parasite Isolation or both, whereas 49 (64%) were negative by both tests. At a cutoff of 1:320, combined values for IFAT sensitivity and specificity were maximized at 96.4 and 67.3%, respectively. The area under the receiver-operating characteristic curve for the IFAT was 0.84. A titer of 1:320 was used as cutoff when screening serum collected from live-sampled sea otters from California (n = 80), Washington (n = 21), and Alaska (n = 65) for T. gondii infection. Thirty-six percent (29 out of 80) of California sea otters (E. lutris nereis) and 38% (8 out of 21) of Washington sea otters (E. lutris kenyoni) were seropositive for T. gondii, compared with 0% (0 out of 65) of Alaskan sea otters (E. lutris kenyoni).
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experimental infection of nude mice as a model for sarcocystis neurona associated encephalitis
Parasitology Research, 1997Co-Authors: Antoinette E. Marsh, Bradd C Barr, Jeffrey Lakritz, Robert W Nordhausen, John E Madigan, Patricia A. ConradAbstract:The development of a rodent model for the study of Sarcocystisneurona 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 Neosporacaninum and Toxoplasmagondii. A time course of infection was examined, and histopathology, immunohistochemistry, and Parasite Isolation were used to examine the pathogenesis and follow the infection from 1 to 6 weeks postinoculation. S.neurona was associated with the development of encephalitis in these mice, and the immune status determined the susceptibility of these mice to S. neurona-associated encephalitis.
Gema Alvarezgarcia - One of the best experts on this subject based on the ideXlab platform.
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bovine chronic besnoitiosis in a calf characterization of a novel b besnoiti isolate from an unusual case report
Veterinary Parasitology, 2017Co-Authors: Carlos Diezmadiaz, Paula Garcialunar, D Gutierrezexposito, Alejandro Jimenezmelendez, Javier Blancomurcia, Luis Miguel Ortegamora, Ignacio Ferre, J A Perezsalas, M Fernandez, Gema AlvarezgarciaAbstract:Abstract Bovine besnoitiosis, caused by the apicomplexan Besnoitia besnoiti , is a chronic and debilitating disease characterized by cutaneous and systemic manifestations that primarily affects adult beef cattle. Previous studies have reported that clinical besnoitiosisis is rare in calves. However, we isolated B. besnoiti from a chronically infected calf for the first time. The identity of the Besnoitia species was determined after Parasite Isolation and molecular genotyping. According to the results obtained in vitro the new isolate, named as Bb-Spain3, was characterized in a reproducible in vitro model and was categorized as a low invader and low prolific isolate with a slower lytic cycle compared to Bb-Spain 1 isolate. Specific traits that differentiate isolates obtained from adult animals from those infecting calves were not found. Next, we described the first case report of chronic besnoitiosis in a female calf less than 6 months-old with a low body condition. The disease was confirmed by the presence of specific anti- B. besnoiti antibodies and Parasite detection in the skin. At post-mortem examination, tissue samples were collected for histological, immunohistochemical and molecular analyses. DNA-Parasite was detected in 31 different calf’s tissues, being the most highly parasitized tissues the skin and the respiratory and reproductive tracts. In addition, the Parasite was also present in heart, eyes, lymph nodes and brain. The high Parasite load, a wide intra-organic Parasite distribution and the presence of both viable and degenerated cysts, were indicative of a rapid progression of the disease. This case report underlines the need to include the inspection of young animals in besnoitiosis control.
