Brain iron accumulation in unexplained fetal and infant death victims with smoker mothers-The possible involvement of maternal methemoglobinemia

<p>Abstract</p> <p>Background</p> <p>Iron is involved in important vital functions as an essential component of the oxygen-transporting heme mechanism. In this study we aimed to evaluate whether oxidative metabolites from maternal cigarette smoke could affect iron homeostasis in the brain of victims of sudden unexplained fetal and infant death, maybe through the induction of maternal hemoglobin damage, such as in case of methemoglobinemia.</p> <p>Methods</p> <p>Histochemical investigations by Prussian blue reaction were made on brain nonheme ferric iron deposits, gaining detailed data on their localization in the brainstem and cerebellum of victims of sudden death and controls. The Gless and Marsland's modification of Bielschowsky's was used to identify neuronal cell bodies and neurofilaments.</p> <p>Results</p> <p>Our approach highlighted accumulations of blue granulations, indicative of iron positive reactions, in the brainstem and cerebellum of 33% of victims of sudden death and in none of the control group. The modified Bielschowsky's method confirmed that the cells with iron accumulations were neuronal cells.</p> <p>Conclusions</p> <p>We propose that the free iron deposition in the brain of sudden fetal and infant death victims could be a catabolic product of maternal methemoglobinemia, a biomarker of oxidative stress likely due to nicotine absorption.</p

Preschool Teachers’ Perspectives About the Engagement of Immigrant and Non-Immigrant Parents in Their Children’s Early Education

The present study explores the perceptions of teachers about the engagement of immigrant and non-immigrant parents in preschool. Data were drawn from a larger evaluation study of a government initiative for preschools in Germany, which was designed to foster inclusive pedagogy and parent cooperation. In these analyses, teachers’ perceptions of the engagement of immigrant parents and non-immigrant parents were rated for each parent group, on a 10-item measure, to identify how teacher ratings varied for the different parent groups. Data from 1397 preschool teachers, employed across 203 preschools, were analyzed using multilevel modeling. This statistical approach takes account of the clustered nature of the data. Teacher ratings of engagement for immigrant and non-immigrant parent groups differed between preschools. Most variability in the ratings could be ascribed to preschool characteristics. In preschools, in which staff held a shared understanding of dealing with cultural diversity and in which the director of the preschool had a multicultural mindset, teachers perceived engagement of parents more positively, especially for immigrant parents. Overall, the findings identified the importance of self-efficacy for inclusion and more positive beliefs about multiculturalism among preschool teachers. Such qualities are important for working with all parents. However, unfavorable social structures, such as those found in disadvantaged areas, may present major challenges for parent cooperation and engagement

Lesión celular del miocardio y actividad de la ATPsintasa mitocondrial en ratas infectadas con una cepa colombiana de Trypanosoma cruzi

Introducción. La enfermedad de Chagas es la principal causa de cardiomiopatía crónica en regiones endémicas de Latinoamérica. Alteraciones en el metabolismo energético mitocondrial cardiaco causadas por Trypanosoma cruzi pueden estar involucradas en el desarrollo de esta cardiomiopatía. Objetivo. En este trabajo se investigó la lesión celular del miocardio de ratas durante una infección por la cepa colombiana Mg8 de Trypanosoma cruzi y la actividad de la ATPsintasa mitocondrial para correlacionar el daño al miocardio con el metabolismo energético mitocondrial. Materiales y métodos. Se utilizaron grupos de cinco ratas, las cuales fueron infectadas con tripomastigotes. El curso de la infección se evaluó a nivel parasitológico, histopatológico y molecular. La actividad de la ATPsintasa mitocondrial del miocardio se evaluó tanto en las ratas infectadas con parásitos como en ratas control no infectadas. Resultados. Se determinaron los días 26 y 60 post-infección como el punto de máxima parasitemia y como el punto de desaparición de los parásitos en sangre circulante, respectivamente. Los resultados histopatológicos y moleculares muestran que la cepa Mg8 tiene tropismo por el tejido cardiaco y causa una considerable lesión celular del miocardio de ratas tanto a 26 días (fase aguda) como a 60 días post-infección (fase crónica). A pesar de la lesión observada, no se encontró diferencia estadísticamente significativa en la actividad de la ATPsintasa de las ratas infectadas en estos días al comparar con sus respectivos controles. Conclusión. Estos resultados sugieren que el metabolismo energético mitocondrial no está alterado en la lesión celular del miocardio de las ratas, observada durante la infección con la cepa colombiana Mg8 de T. cruzi