Campo magnético de frecuencia extremadamente baja: Seguridad de su aplicación a nivel del sistema nervioso central / Magnetic field of extremely low frequency: Safety of its application at the level of the central nervous system

Introducción: La enfermedad cerebrovascular constituye un importante problema de salud a nivel mundial. En la actualidad se desarrollan investigaciones científicas dedicadas al estudio de los efectos del campo magnético de frecuencia extremadamente baja para su tratamiento. No es suficientemente clara la información acerca de su inocuidad en las dosis estudiadas. Objetivo: Estudiar la seguridad de la aplicación del campo magnético de frecuencia extremadamente baja a nivel del sistema nervioso central a través de un estudio toxicológico a dosis aguda, repetida y ensayo de micronúcleos en médula ósea. Métodos: Se conformaron tres grupos experimentales con ratas Sprague Dawley Cenp:SPRD jóvenes y sanas para los experimentos de toxicidad y ratones CENP: NMRI para la evaluación mutagénica. Se utilizaron controles negativos no tratados. En el ensayo de micronúcleos se incorporó un grupo control positivo al que se administró Ciclofosfamida por vía intraperitoneal. Se aplicó un campo magnético no homogéneo con niveles de inducción magnética de 6,5 y 15 mT, tomando como referencia el valor máximo sobre la superficie de la bobina. Para la aplicación del campo magnético la bobina estimuladora se colocó sobre la cabeza asegurando la exposición completa del encéfalo. Resultados: En ninguno de los ensayos se detectaron signos de toxicidad. Se comprobó así mismo que no se indujeron efectos genotóxicos ni citotóxicos sobre las células somáticas. Conclusiones: El tratamiento con campo magnético de frecuencia extremadamente baja a nivel del sistema nervioso central en las condiciones experimentales y dosis estudiadas es seguro(AU)

Introduction: Stroke is a major health problem all over the world. Nowadays are developed scientific researches devoted to the study of extremely low frequency magnetic field effects over this illness. The information about it safety is unclear yet. Objective: To study the safety of extremely low frequency magnetic field applied at central nervous system level wasby means ofa toxicological assay (Acute, repeated doses and micronucleus in bone marrow assay) Methods: Three experimental groups were made with Sprague Dawley Cenp: SPRD young and healthy rats for toxicity experiments and CENP: NMRI mice for mutagen evaluation. Untreated negative controls were used. In the micronucleus assay, an additional positive control group was included. This group received Cyclophosphamide by intraperitoneal administration. Was applied a non-homogenousmagnetic fieldof 6,5 and 15 mT, taken as reference the maximum value over the coil surface. The coil was positioned over the head, ensuring full exposure of brain to magnetic field. Results : In none of trials were detected any sign of toxicity. It was also found no genotoxic or cytotoxic effects induced on somatic cells. Conclusions : These results indicated the safety of treatmentwith extremely low frequency magnetic field at central nervous system level for experimental conditions and doses studied(AU)

Utilidad del cribado toxicológico en pediatría / Toxicology screening in paediatrics

No disponible

Sinais clínicos e patologia da intoxicação crônica experimental de caprinos por palicourea marcgravii / Clinical signs and pathology of chronic experimental poisoning by palicourea marcgravii in goats

Palicourea marcgravii é considerada a principal planta tóxica de interesse pecuário no Brasil, porém, até o momento, é conhecido apenas o quadro agudo da intoxicação. Esse estudo avaliou as alterações clínico-patológicas de 10 caprinos cronicamente intoxicados por P. marcgravii. Os animais receberam, diariamente, 0,2g/kg de peso corporal da planta fresca por 6 a 38 dias. Os caprinos apresentaram como principais sinais clínicos anorexia, apatia, taquicardia, arritmia, pulso venoso jugular positivo e decúbito. Nas necropsias, os achados macroscópicos foram hidropericárdio, palidez dos rins e do miocárdio, atrofia gelatinosa da gordura cardíaca, evidenciação do padrão lobular hepático e edema pulmonar. Os principais achados microscópicos foram tumefação e vacuolização de cardiomiócitos, necrose de fibras cardíacas e infiltrado inflamatório mononuclear no miocárdio. Nos rins foi encontrada marcante degeneração hidrópico-vacuolar difusa. Os achados demonstraram nos caprinos cronicamente intoxicados, quadro clínico-patológico com características distintas do observado na forma aguda da intoxicação por P. marcgravii. Essas observações comprovam o risco para caprinos da ingestão da planta, mesmo que em pequenas doses, resultando no surgimento de quadro clínico e graves lesões ainda pouco conhecidas, e que poderiam ser confundidas com outras enfermidades.

Palicourea marcgravii is considered the main toxic plant for livestock in Brazil, however, only the acute intoxication has been reported. This study reports the clinical and pathological changes of 10 goats chronically intoxicated by P. marcgravii. The animals received, daily, 0.2g/kg body weight of the fresh plant during 6 to 38 days. The main clinical signs were anorexia, lethargy, tachycardia, arrhythmia, positive jugular venous pulse and recumbency. At necropsies, the lesions were pale kidneys and myocardium, serous atrophy of cardiac fat, evident hepatic lobular pattern and pulmonary edema. The main microscopic findings were swelling and vacuolization of cardiomyocytes, cardiac necrosis and inflammatory mononuclear infiltrate of the myocardium. The kidneys showed diffuse vacuolar hydropic degeneration of the epithelium. These findings demonstrated that goats chronically intoxicated by P. marcgravii show distinct clinicopathologic features than those observed in the acute form of the poisoning. It is suggested that goats may be spontaneously become intoxicated by the ingestion of small repeated doses of the plant and that the poisoning can be confused with other diseases.

Efectos tóxicos de alternariol por ensayos in vitro: revisión / Toxic effects of alternariol by in vitro assays: a review

Las micotoxinas son metabolitos secundarios producidos por hongos del genero Aspergillus, Penicillium, Fusarium y Alternaria. Las micotoxinas más abundantes son aflatoxinas (Aspergillus), ocratoxina A (Penicillium), fumonisinas, zearalenona, deoxinivalenol (Fusarium) y alternariol (Alternaria). De las especies de Alternaria, A. alternata es la especie productora más importante de micotoxinas. Todas están consideradas como contaminantes tóxicos que están presentes en alimentos de consumo diario. Esta revisión se centra en estudios in vitro relacionados con la respuesta y citotoxicidad a la micotoxina de Alternaria, alternariol (AOH). Para ello, se ha realizado una búsqueda bibliográfica de los artículos de AOH disponible en bases de datos como: Pubmed, Scopus, Science Direct y Current Contents en los últimos catorce años. Así pues, el objetivo de la revisión bibliográfica es evaluar los efectos de AOH investigados mediante ensayos in vitro (AU)

Mycotoxins are secondary metabolites produced by genera fungus of: Aspergillus, Penicillium, Fusarium and Alternaria. The most frequent mycotoxins are: aflatoxins (Aspergillus), ochratoxin A (Penicillium), fumonisins, zearalenone, deoxynivalenol (Fusarium) and alternariol (Alternaria). Among all Alternaria spp, A. Alternata is the most producer mycotoxin. All mycotoxins are considered toxic contaminants present in food of daily consumption. This review is based on in vitro studies where response and toxicity in cells of Alternaria mycotoxin, alternariol (AOH) have been carried out. In this sense a bibliographic search of AOH papers available in on-line data bases such as: Pubmed, Scopus, Science Direct and Current Contents in the last fourteen years, have been collected. The main objective of this bibliographic review is to evaluate the AOH effects detected in in vitro assay (AU)