Antimicrobial and toxicological evaluation of Origanum vulgare: an in vivo study / Avaliação antimicrobiana e toxicológica de Origanum vulgare: um estudo in vivo

Origanum vulgare has been of great interest in academia and pharma industry due to its antioxidant, antifungal and antitumor properties. The present study aimed to find the anti-MRSA potential and in vivo toxicity assessments of O. vulgare. O. vulgare extract was used to monitor anti-MRSA activity in mice. Following MRSA established infection in mice (Mus musculus), treatment with O. vulgare was continued for 7 days. Autopsies were performed and re-isolation, gross lesion scoring and bacterial load in various organs were measured. Additionally, blood sample was analysed for hematological assays. Toxicity assessment of O. vulgare potential as medicine was done at 200 mg/kg and 400 mg/kg by evaluating liver and kidney functions. Bacterial load and gross lesion in lungs and heart were significantly low compared to positive control following O. vulgare treatment. Likewise, O. vulgare treated groups had hematological, neutrophil and TLC values similar to control groups. Increased AST, ALP and total bilirubin along with marked hepatocellular degeneration and distortion around the central vein, inflammatory cell infiltration, and cytoplasmic vacuolization of hepatic cells was observed at higher dose. It is concluded that crude extract of O. vulgare may contain beneficial secondary metabolites and in future may be explored for curing infectious diseases.(AU)

Origanum vulgare tem despertado grande interesse na academia e na indústria farmacêutica devido às suas propriedades antioxidantes, antifúngicas e antitumorais. O presente estudo teve como objetivo encontrar o potencial anti-MRSA e avaliações de toxicidade in vivo de O. vulgare. O extrato de O. vulgare foi usado para monitorar a atividade anti-MRSA em camundongos. Após infecção estabelecida por MRSA em camundongos (Mus musculus), o tratamento com O. vulgare foi continuado por 7 dias. As autópsias foram realizadas e o reisolamento, pontuação das lesões grosseiras e carga bacteriana em vários órgãos foram medidos. Além disso, a amostra de sangue foi analisada para ensaios hematológicos. A avaliação da toxicidade do potencial de O. vulgare como medicamento foi feita com 200 mg / kg e 400 mg / kg, avaliando as funções hepática e renal. A carga bacteriana e as lesões graves nos pulmões e no coração foram significativamente baixas em comparação com o controle positivo após o tratamento com O. vulgare. Da mesma forma, os grupos tratados com O. vulgare apresentaram valores hematológicos, de neutrófilos e de TLC semelhantes aos grupos de controle. Aumento de AST, ALP e bilirrubina total juntamente com degeneração hepatocelular marcada e distorção ao redor da veia central, infiltração de células inflamatórias e vacuolização citoplasmática de células hepáticas foram observados em doses mais altas. Conclui-se que o extrato bruto de O. vulgare pode conter metabólitos secundários benéficos e, no futuro, pode ser explorado para a cura de doenças infecciosas.(AU)

Antimicrobial and toxicological evaluation of Origanum vulgare: an in vivo study / Avaliação antimicrobiana e toxicológica de Origanum vulgare: um estudo in vivo

Origanum vulgare has been of great interest in academia and pharma industry due to its antioxidant, antifungal and antitumor properties. The present study aimed to find the anti-MRSA potential and in vivo toxicity assessments of O. vulgare. O. vulgare extract was used to monitor anti-MRSA activity in mice. Following MRSA established infection in mice (Mus musculus), treatment with O. vulgare was continued for 7 days. Autopsies were performed and re-isolation, gross lesion scoring and bacterial load in various organs were measured. Additionally, blood sample was analysed for hematological assays. Toxicity assessment of O. vulgare potential as medicine was done at 200 mg/kg and 400 mg/kg by evaluating liver and kidney functions. Bacterial load and gross lesion in lungs and heart were significantly low compared to positive control following O. vulgare treatment. Likewise, O. vulgare treated groups had hematological, neutrophil and TLC values similar to control groups. Increased AST, ALP and total bilirubin along with marked hepatocellular degeneration and distortion around the central vein, inflammatory cell infiltration, and cytoplasmic vacuolization of hepatic cells was observed at higher dose. It is concluded that crude extract of O. vulgare may contain beneficial secondary metabolites and in future may be explored for curing infectious diseases.

Origanum vulgare tem despertado grande interesse na academia e na indústria farmacêutica devido às suas propriedades antioxidantes, antifúngicas e antitumorais. O presente estudo teve como objetivo encontrar o potencial anti-MRSA e avaliações de toxicidade in vivo de O. vulgare. O extrato de O. vulgare foi usado para monitorar a atividade anti-MRSA em camundongos. Após infecção estabelecida por MRSA em camundongos (Mus musculus), o tratamento com O. vulgare foi continuado por 7 dias. As autópsias foram realizadas e o reisolamento, pontuação das lesões grosseiras e carga bacteriana em vários órgãos foram medidos. Além disso, a amostra de sangue foi analisada para ensaios hematológicos. A avaliação da toxicidade do potencial de O. vulgare como medicamento foi feita com 200 mg / kg e 400 mg / kg, avaliando as funções hepática e renal. A carga bacteriana e as lesões graves nos pulmões e no coração foram significativamente baixas em comparação com o controle positivo após o tratamento com O. vulgare. Da mesma forma, os grupos tratados com O. vulgare apresentaram valores hematológicos, de neutrófilos e de TLC semelhantes aos grupos de controle. Aumento de AST, ALP e bilirrubina total juntamente com degeneração hepatocelular marcada e distorção ao redor da veia central, infiltração de células inflamatórias e vacuolização citoplasmática de células hepáticas foram observados em doses mais altas. Conclui-se que o extrato bruto de O. vulgare pode conter metabólitos secundários benéficos e, no futuro, pode ser explorado para a cura de doenças infecciosas.

Perfil hematológico e bioquímico de roedores de laboratório alimentados com rações contendo diferentes fontes lipídicas e métodos de esterilização / Hematological and biochemical profile of laboratory rodents feeded with rations containing different lipid sources and sterilization methods

Objetivou-se com esse estudo avaliar os efeitos de diferentes métodos de esterilização e fontes de óleo (salmão e linhaça) em formulação de rações sobre os parâmetros bioquímicos e hematológicos de ratos Wistar e camundongos NIH em diferentes idades. Foram avaliados 336 animais, sendo 168 de cada biomodelo. Houve efeito significativo das fontes de óleo sobre os parâmetros bioquímicos plasmáticos em camundongos NIH e ratos Wistar (P 0,05). Conclui-se que o óleo de salmão e linhaça podem ser utilizados nas rações para camundongos NIH e ratos Wistar, independente do método de esterilização adotado.(AU)

The objective of this study was to evaluate the effects of different methods of sterilization and oil sources (salmon and flaxseed) in the formulation of diets on the biochemical and hematological parameters of Wistar rats and NIH mice at different ages. 336 animals were evaluated, 168 from each biomodel. There was a significant effect of oil sources on plasma biochemical parameters in NIH mice and Wistar rats (P < 0.05). There were no significant effects of the sterilization methods on any evaluated parameter (P > 0.05). It was concluded that salmon and linseed oil can be used in diets for NIH mice and Wistar rats, regardless of the sterilization method adopted.(AU)

Perfil hematológico e bioquímico de roedores de laboratório alimentados com rações contendo diferentes fontes lipídicas e métodos de esterilização / Hematological and biochemical profile of laboratory rodents feeded with rations containing different lipid sources and sterilization methods

Objetivou-se com esse estudo avaliar os efeitos de diferentes métodos de esterilização e fontes de óleo (salmão e linhaça) em formulação de rações sobre os parâmetros bioquímicos e hematológicos de ratos Wistar e camundongos NIH em diferentes idades. Foram avaliados 336 animais, sendo 168 de cada biomodelo. Houve efeito significativo das fontes de óleo sobre os parâmetros bioquímicos plasmáticos em camundongos NIH e ratos Wistar (P 0,05). Conclui-se que o óleo de salmão e linhaça podem ser utilizados nas rações para camundongos NIH e ratos Wistar, independente do método de esterilização adotado.

The objective of this study was to evaluate the effects of different methods of sterilization and oil sources (salmon and flaxseed) in the formulation of diets on the biochemical and hematological parameters of Wistar rats and NIH mice at different ages. 336 animals were evaluated, 168 from each biomodel. There was a significant effect of oil sources on plasma biochemical parameters in NIH mice and Wistar rats (P 0.05). It was concluded that salmon and linseed oil can be used in diets for NIH mice and Wistar rats, regardless of the sterilization method adopted.

Efeito agudo nos níveis sanguíneos de colesterol, lactato e glicose em camundongos na atividade física em ambiente enriquecido / Acute effect on cholesterol, lactate and blood glucose levels in mice on physical activity in enriched environment

O objetivo desse estudo foi verificar o efeito agudo da atividade física em alojamento com ambiente enriquecido nos níveis de colesterol, lactato e glicose sanguíneos em camundongos C57BL/6. Esse ambiente era composto por gangorra, rodas, bolas e túneis. As variáveis bioquímicas foram analizados em grupos de camundongos C57BL/6 antes e imediatamente após uma sessão de 30 minutos de atividade física em ambiente enriquecido. Em cada grupo foi coletada uma amostra de sangue para avaliação específica. No grupo 1 (n=5) foi avaliado o nível de lactato sanguíneo; no grupo 2 (n=5) foi avaliado o nível da glicose sanguínea; no grupo 3 (n=3) foi avaliado o nível do colesterol total. A atividade física em ambiente enriquecido provocou aumento agudo da lactatemia (p=0,043) imediatamente após a sessão experimental. Em relação aos níveis de glicose sanguínea (p=0,684) e colesterol total (p=0,102), não houve mudanças significativas. Os resultados desse estudo, mostram que a atividade física em alojamento com ambiente enriquecido promove adaptações agudas nos sistemas de fornecimento de energia dos animais, validando a viabilidade dessa proposta metodológica como formato experimental da atividade física com roedores.(AU)

The aim of this study was to verify the acute effect of physical activity in housing with an enriched environment on blood cholesterol, lactate and glucose levels in C57BL/6 mice. This environment consisted of seesaw, wheels, balls and tunnels. Biochemical variables were analyzed in groups of C57BL/6 mice before and immediately after a 30-minute session of physical activity in an enriched environment. In each group, a blood sample was collected for specific evaluation. In group 1 (n=5) the blood lactate level was evaluated; in group 2 (n=5) the blood glucose level was assessed; in group 3 (n=3) the level of total cholesterol was assessed. Physical activity in an enriched environment caused an acute increase in lactatemia (p=0.043) immediately after the experimental session. Regarding blood glucose levels (p=0.684) and total cholesterol (p=0.102), there were no significant changes. The results of this study show that physical activity in accommodation with an enriched environment promotes acute adaptations in the energy supply systems of animals, validating the viability of this methodological proposal as an experimental format for physical activity with rodents.(AU)

Efeito agudo nos níveis sanguíneos de colesterol, lactato e glicose em camundongos na atividade física em ambiente enriquecido / Acute effect on cholesterol, lactate and blood glucose levels in mice on physical activity in enriched environment

O objetivo desse estudo foi verificar o efeito agudo da atividade física em alojamento com ambiente enriquecido nos níveis de colesterol, lactato e glicose sanguíneos em camundongos C57BL/6. Esse ambiente era composto por gangorra, rodas, bolas e túneis. As variáveis bioquímicas foram analizados em grupos de camundongos C57BL/6 antes e imediatamente após uma sessão de 30 minutos de atividade física em ambiente enriquecido. Em cada grupo foi coletada uma amostra de sangue para avaliação específica. No grupo 1 (n=5) foi avaliado o nível de lactato sanguíneo; no grupo 2 (n=5) foi avaliado o nível da glicose sanguínea; no grupo 3 (n=3) foi avaliado o nível do colesterol total. A atividade física em ambiente enriquecido provocou aumento agudo da lactatemia (p=0,043) imediatamente após a sessão experimental. Em relação aos níveis de glicose sanguínea (p=0,684) e colesterol total (p=0,102), não houve mudanças significativas. Os resultados desse estudo, mostram que a atividade física em alojamento com ambiente enriquecido promove adaptações agudas nos sistemas de fornecimento de energia dos animais, validando a viabilidade dessa proposta metodológica como formato experimental da atividade física com roedores.

The aim of this study was to verify the acute effect of physical activity in housing with an enriched environment on blood cholesterol, lactate and glucose levels in C57BL/6 mice. This environment consisted of seesaw, wheels, balls and tunnels. Biochemical variables were analyzed in groups of C57BL/6 mice before and immediately after a 30-minute session of physical activity in an enriched environment. In each group, a blood sample was collected for specific evaluation. In group 1 (n=5) the blood lactate level was evaluated; in group 2 (n=5) the blood glucose level was assessed; in group 3 (n=3) the level of total cholesterol was assessed. Physical activity in an enriched environment caused an acute increase in lactatemia (p=0.043) immediately after the experimental session. Regarding blood glucose levels (p=0.684) and total cholesterol (p=0.102), there were no significant changes. The results of this study show that physical activity in accommodation with an enriched environment promotes acute adaptations in the energy supply systems of animals, validating the viability of this methodological proposal as an experimental format for physical activity with rodents.

Hematology of Swiss mice (Mus musculus) of both genders and different ages.

PURPOSE: To describe the hematologic values of male and female, young and adult, Swiss mice (Mus musculus). METHODS: Mus musculus (n=14) were randomly selected and separated by gender. The male and female, young and adult animals were sedation to obtain a blood sample, by intracardiac route at 30, 45, 60, 75, 90, 105 and 120 days after birth. RESULTS: The Swiss mouse hemogram values obtained, in relation to total eosinophils, basophils, and number of platelets, there was no statistical differences according to the genders or the age of the animals. Regarding the erythrocyte, hemoglobin and hematocrit values obtained, these were higher in females. The RDW-CD and MPV values were higher in the females than in the males. CONCLUSIONS: Lymphocytes are the predominant cells in the peripheral blood. The collection of 800 µL of blood by intracardiac route, every 15 days, did not affect the health of the animals. Analyses of the blood samples contribute to the experimental models provided by the Central Animal Facility of UFMS and used by professors.

Hematology of Swiss mice (Mus musculus) of both genders and different ages

PURPOSE: To describe the hematologic values of male and female, young and adult, Swiss mice (Mus musculus). METHODS: Mus musculus (n=14) were randomly selected and separated by gender. The male and female, young and adult animals were sedation to obtain a blood sample, by intracardiac route at 30, 45, 60, 75, 90, 105 and 120 days after birth. RESULTS: The Swiss mouse hemogram values obtained, in relation to total eosinophils, basophils, and number of platelets, there was no statistical differences according to the genders or the age of the animals. Regarding the erythrocyte, hemoglobin and hematocrit values obtained, these were higher in females. The RDW-CD and MPV values were higher in the females than in the males. CONCLUSIONS: Lymphocytes are the predominant cells in the peripheral blood. The collection of 800 µL of blood by intracardiac route, every 15 days, did not affect the health of the animals. Analyses of the blood samples contribute to the experimental models provided by the Central Animal Facility of UFMS and used by professors. .

Rapid quantification of resveratrol in mouse plasma by ultra high pressure liquid chromatography (UPLC) coupled to tandem mass spectrometry.

OBJECTIVE: The objective of this study was to develop a rapid and sensitive method for the quantification of resveratrol, a polyphenolic compound with multiple health beneficial effects, in mouse plasma. METHODS: We used reversed-phase ultra high pressure-liquid chromatography with tandem mass spectrometry detection for the determination of resveratrol levels in mouse plasma. An Agilent Zorbax Eclipse Plus C18 column (2.1 mm x 50 mm, 1.8 µm) was used as the stationary phase. The mobile phase consisted of a gradient formed using 1 mM ammonium fluoride and methanol. RESULTS: Using this improved method, we obtained a retention time of 2.2 min and a total run time of 5 min, for resveratrol. The calibration curve for resveratrol showed a linear range from 0.5 to 100 ng/mL. The average coefficient of variation was 6% for interday variation and 4% for intraday variation. The recovery for resveratrol in mouse plasma was 85 ± 10% (mean ± standard deviation). CONCLUSION: The method presented herein allows a rapid and very sensitive quantification of resveratrol in mouse plasma at concentrations as low as 500 ppt.

Genotoxic effects in blood cells of Mus musculus and Iguana iguana living near coal mining areas in Colombia.

Coal is a mixture of chemicals with the capacity of promoting biochemical changes that may lead to DNA damage. In this study, the comet assay in peripheral blood cells, and the micronucleus test in blood smears were used to evaluate potential genotoxic effects derived from exposure to coal mining activities on wild populations of Mus musculus and Iguana iguana. Four locations from Colombia were evaluated: La Loma and La Jagua de Ibirico, two municipalities located near coal mining fields at the Department of Cesar; and Valledupar and Arjona, cities used as reference sites, both localized at least 100 and 200km far from the mines, respectively. Compared to Valledupar and Arjona, animals collected in close proximity to coal mining areas showed highest percentages of DNA damage for both species, evidencing that living around coal mining fields may result in an increase of DNA lesions in blood cells of rodents and reptiles. The results for micronucleus test were conflicting. Mice from Arjona had greater number of cells with micronucleus than those from the other studied locations, probably as a result of infection found by blood parasites. In summary, it was demonstrated that animals living around coal mining areas have a greater chance of having DNA damage, as measured by the comet assay, than those from sites far from the coal dust source.

Estudio cariométrico de placentas de ratones con infección aguda por diferentes cepas de Trypanosoma cruzi / Karyometric study of placentas from mice with acute infection by different strains of Trypanosoma cruzi

El objetivo de este trabajo fue evaluar cariometricamente las alteraciones causadas por diferentes cepas de T. cruzi en la placenta del ratón. Ratones hembras de 60 días, grávidas, fueron inoculadas, intraperitonealmente, con 2 x 10(5) tripomastigotes sanguíneos de las cepas colombiana, Y, Solivia o RC del T. cruzi. Fueron observadas claras diferencias en las alteraciones cariométricas de las células trofoblásticas gigantes y de las células trofoblásticas de la zona esponjosa. Los resultados demostraron que las cepas colombiana y RC causan alteraciones tanto en las células trofoblásticas gigantes como en las células del trofoblasto esponjoso, mientras que las cepas Y y Bolivia provocan alteraciones solamente en las células trofoblásticas gigantes. Es posible concluir que cada cepa posee características propias y que, a pesar del tipo similar de transmisión, presenta matices diferenciales en el proceso de la patogénesis placentaria.

The objective of this work was to evaluate karyometrically the alterations caused by different strains of Trypanosoma cruzi in the mouse placenta. Pregnant mice, 60-day old, were intraperitoneally inoculated with 2 x 10(5) bloodstream trypomastigotes of the Colombian, Y, Bolivia or RC strain of T cruzi. There were observed clear differences in the karyometric alterations of the trophoblast giant cells and in the spongiotrophoblast cells. The results demonstrate that the Colombian and RC strains cause alterations both in the trophoblast giant cells and in the spongiotrophoblast cells, whereas the Y and Bolivia strains provoke alterations only in the trophoblast giant cells. It is possible concluding that each strain has its own characteristics and that, in spite of the similar type of transmission, it show differential nuances in the placental pathogenic process.

Estudio morfométrico del hígado de ratón en la enfermedad de Chagas experimental / Morphometrical study of the mouse liver in the experimental Chagas' disease

El objetivo de este trabajo fue caracterizar histopatológicamente y morfométricamente las alteraciones del tejido hepático de ratón, durante la fase aguda de la infección por la cepa MORC-2 de Trypanosoma cruzi. Esta cepa mostró acentuado tropismo por el hígado, con numerosos nidos de amastigotes en los cortes examinados. El hígado de los animales infectados estaba constituido por células menores, con citoplasma granuloso. En algunas áreas, los sinusoides estaban congestionados y las células de Kupffer hipertróficas e hiperplásicas. El tejido hepático mostró focos circunscritos de células inflamatorias en áreas de necrosis, sinusoides, en torno de las venas centrolobulillares y de los espacios porta. La vena centrolobulillar estaba dilatada y congestionada, con necrosis focales y ruptura de la pared en algunos campos. Los espacios porta estaban desorganizados, a veces, con intenso infiltrado inflamatorio. En algunas áreas fue posible observar degeneración cística (spongis hepatis). Por todo el tejido hepático se observaron nidos de amastigotes, de tamaño variable, algunos rodeados por infiltrado inflamatorio crónico. En el espacio porta, el volumen relativo de los conductos biliares y vasos sanguíneos, así como la densidad de superficie de las arterias fueron mayores en el grupo infectado.

The objective of this work was to characterize histopatologically and morphometrically the alterations of the mouse liver during the acute infection by the MORC-2 strain of Trypanosoma cruzi. This strain showed marked tropism by the liver, with numerous nests of amastigotes in the examined sections. The liver of the infected animals was constituted by smaller cells, with granular cytoplasm. In some areas, the sinusoids were congested and the Kuppfer cells were hipertrofied and hiperplasic. The hepatic tissue showed circumscribed foci of inflammatory cells into necrotic areas, sinusoids, around the contrilobular veins and the portal spaces. The centrilobular vein was dilated and congested, with focal necrosis and rupture of the wall in some regions. The portal spaces were disorganized, sometimes with intense inflammatory infiltrate. In some areas it was possible to observe cystic degeneration (spongis hepatis). In the hepatic tissue, nests of amastigotes, of variable sizes, were observed, some surrounded by chronic inflammatory infiltrate. In the portal space, the relative volume of the biliary ducts and blood vessels, as well as the surface density of the arteries was greater in the infected group.

Thermal acclimation and seasonal variations of erythrocyte size in the Andean mouse Phyllotis xanthopygus rupestris.

Seasonal hematological adjustments in small mammals may include changes in the number and size of the red cells or changes in other linked blood parameters. The direction and magnitude of these changes vary in different species. We hypothesized that the observed variations of the red cell adjustments could be directly related to the magnitude of the seasonal temperature differential, and predicted that the annual red cell size variation in rodents from environments with marked seasonal changes would tend to disappear, if the animals were raised under milder and constant environments. To test this idea, we got field blood samples from the Andean species Phyllotis xanthopygus rupestris enduring a winter-summer thermal differential of at least 20 degrees C. These animals had significantly smaller erythrocytes during the winter. Contrary to our prediction, their offspring born and raised under constant temperature conditions showed a similar trend. Unless the effective environmental cue differed from the one we used, these results favor the idea of a genetically determined annual red cell size variation that occurs independent of thermal acclimation and acclimatization.

Leptospiral carriage by Mice and Mongooses on the island of Barbados

Leptospirosis is a zoonotic disease, maintained by chronic infection of the kidneys of reservoir animals, usually small mammals. Infection in humans is acquired from direct or indirect exposure to the urine of infected animals. Leptospirosis has a high incidence in tropical regions, and has been studied extensively in several Caribbean countries. We studied the carriage of Leptospira serovars by two small mammals which are potential maintenance host of the disease in Barbados. A total of 136 mongooses (Herpestes auropunctatus) and 97 mice (Mus musculus) were caught in live traps. Leptospiral antibodies were detected by microscopic aggutination test (MAT) using antigens representing 12 serogrouops, and kidney tissues were inoculated into polysorbate medium for isolation of leptospires. The seroprevalence (at a titre of o 100) in mice was 28.2 percent (24/85, 95 percent CI 19.0, 39.1) and in mongooses 40.7 percent (48/118, 95 percent CI 20.1, 39.0) and from 4 mongooses ( 2.9 percent, 95 percent, CI 0.8, 7.4). Mouse isolates were identified as serovars arborea (17) and bim (7). As in other parts of the world, common house mice (Mus musculus) represent a significant reservoir of leptospirosis. Although carriage of the Ballum serovar, arborea, was not unexpected, this represents the first time that an animal reservoir of serovar bim has been identified. This is significant because bim causes about 63 percent of human leptospirosis in Barbados, and control efforts and education for prevention can now be targeted at a specific reservoir. (AU)

Infectivity of cysts of the ME-49 Toxoplasma gondii strain in bovine milk and homemade cheese

Objetivo: Analisar a infecciosidade e a resistência de cistos de T. gondii em leite e queijo fresco caseiro, pela infecção artificial de leite bovino. Métodos: O leite bovino pasteurizado foi infectado artificialmente com 10 cistos/ml de T.gondii cepa ME49 e inoculado em grupos de camundongos, imediatamente ou após ser estocado por 5, 10 e 20 dias a 4oC. Preparou-se queijo fresco caseiro com leite infectado, sendo testado em grupos de camundongos, utilizando a mesma conservação. A infecção foi detectada pela presença de cistos no cérebro dos camundongos desafiados ou testes sorológicos após cinco semanas, também confirmada por Western Blotting e histologia. Resultados: A infecciosidade dos cistos da cepa ME49 de T.gondii foi mantida mesmo quando armazenado no leite até 20 dias de conservação em condições de refrigeração a 4oC. Os cistos resistiram ao processo de fabricação do queijo e eram infectantes após um período de 10 dias nas mesmas condições. Conclusões: Os achados mostraram que o leite e seus derivados podem ser uma importante fonte de contaminação humana pelo T.gondii, reforçando a importância da pasteurização do leite antes de qualquer processamento ou ingestão

Evaluación de un conjugado anti-IgG de ratón-fluoresceína mediante técnicas de inmunofluorescencia indirecta y citometría de flujo / Evaluation of an anti-IgG conjugate of mouse-fluorescin by the indirect immunofluorescent techniques and flow citomerty

Se purificó una inmunoglobulina G de ratón a partir de suero por cromatografía de afinidad en proteína A. Con esta preparación se inmunizaron los conejos cuyos sueros fueron capaces de reconocer al antígeno inyectado mediante inmunodifusión doble. Los anticuerpos fueron precipitados del suero de conejo y purificados mediante cromatografía de intercambio iónico. Esta preparación fue conjugada a isotiocianato de fluorescencia según la tecnología convencional. El conjugado obtenido fue evaluado con las cepas de referencia de virus Parainfluenza 1, 2, 3; Adenovirus; virus sincitial respiratorio y virus influenza A y B por una técnica de inmunofluorescencia indirecta y muestras positivas de VIH mediante citometría de flujo. En ambos casos se utilizaron anticuerpos monoclonales específicos. Se evaluaron muestras clínicas de pacientes con infección respiratoria aguda

Estandarización de la reacción de polimerización en cadena en muestras de sangre de ratones infectados con Trypasonoma cruzi / Standarization of the polymerase chain reaction in blood samples of mice infected with Trypasonoma cruzi

Se estandarizó la reacción de polimerización en cadena (PCR) para el diagnóstico parasitológico de la enfermedad de Chagas. Se determinó condiciones de estandarización de DNA, así como las concentraciones óptimas de dNTPs, partidores, Taq DNA polimerasa y las condiciones de termociclación. Se determinó que el ensayo es capaz de amplificar hasta 100 fg de DNa templado de trypasonoma cruzi, con una sensibilidad diagnóstica de 2x10² parásitos/ml. Los productos de PCR amplificados demostraron ser específicos mediante ensayos de hibridación con una sonda de DNA kinetoplastídico de T. cruzi

Desarrollo del virus de la encefalitis equina venezolana en el tejido nervioso de ratones recién nacidos: ultraestructura e histoquímica / Ultrastructural and histochemical: study on the development of venezuelan equine encephalitis virus in the central nervous system of newborn mice

Se estudio la estructura del tejido nervioso de ratones recién nacidos inoculados con el virus de la EEV. Las células gliales mostraron hichamiento y aumento del glucógeno; las neuronas presentaron alteraciones en la estructura de las mitocondrias y en la organización de los ribosomas; el complejo de Golgi presentó gran desarrollo y tortuosidad de sus cisternas. La actividad de fosfatasa ácida en la cisterna perinuclear y en el retículoendoplasmático granular, sugiere un aumento de producción de esta enzima en las neuronas invadidas por el virus de la EEV. Se estudió la localización de las partículas virales en relación con la viremia y diseminación de la infección, destacándose la presencia de partículas virales en la luz de los vasos sanguíneos y alrededor de las vainas de mielina de algunos axones. El desarrollo de las partículas virales se comparó con las observaciones hechas en otras arbovirosis, proponiéndose que los precursores virales se originen en masas de viroplasma, desde donde migran a través del citoplasma, hacia las cisternas y vacuolas del complejo de Golgi o hacia la membrana plasmática, transformándose en partículas virales maduras por gemación

GABA metabolism in venezuelan equine encephalomyelitis virus infection: preliminary communication / Metabolismo de GABA en la infección producida por el virus de la encefalitis equina venezolana

Mice infected with venezuelan equine encephalomyelitis virus showed a significant decrease in GABA content of cerebral hemispheres. Activity of the enzyme which synthesizes GABA, glutamic acid decarboxylase, is also reduced in whole cerebral hemispheres, caudate nucleus, and frontal cortex of infected animals, as compared to values obtained from the same regions of control mice

Comparative study of different methods used to isolated Trypanosoma cruzi from defibrinated blood of irradiated mice

Different methods are being used for the isolation and purification of Trypanosoma cruzi blood forms from infected vertebrate hosts. In this study we compare four of these methods (differential centrifugation, Ficoll-Hypaque, Histopaque 1077 and metrizamide) in terms of parasite recovery rates, contamination with cells, duration of the process and role of host irradiation. male albino Swins mice irradiated in a Gamma Cell 220 (500 rads) were inoculated with CL and VL-10 T. cruzi strains and bled at the peak of parasitemia. Infected defibrinated blood was then used for the isolation. Although all methods permitted the recovery of viable trypomastigotes, the best results were obtained with Ficoll-Hypaque and Histopaque 1077. Recovery rates ranged between 71% to 88% and parasite-enriched preparations were obtained in approximately 75 min. irradiation and blood defibrination drastically reduced platelet and leukocyte contamination of the preparations