Interaction of mercury and selenium in the larval stage zebrafish vertebrate model

© The Royal Society of Chemistry 2015.The compounds of mercury can be more toxic than those of any other non-radioactive heavy element. Despite this, environmental mercury pollution and human exposure to mercury are widespread, and are increasing. While the unusual ability of selenium to cancel the toxicity of mercury compounds has been known for nearly five decades, only recently have some aspects of the molecular mechanisms begun to be understood. We report herein a study of the interaction of mercury and selenium in the larval stage zebrafish, a model vertebrate system, using X-ray fluorescence imaging. Exposure of larval zebrafish to inorganic mercury shows nano-scale structures containing co-localized mercury and selenium. No such co-localization is seen with methylmercury exposure under similar conditions. Micro X-ray absorption spectra support the hypothesis that the co-localized deposits are most likely comprised of highly insoluble mixed chalcogenide HgS<inf>x</inf>Se<inf>(1-x)</inf> where x is 0.4-0.9, probably with the cubic zincblende structure

Congenital dermoid inclusion cyst over the anterior fontanel: report of three cases Cisto dermóide de inclusão congênita sobre a fontanela anterior: relato de três casos

Congenital dermoid inclusion cyst over the anterior fontanel (CDIC) is an uncommon cystic lesion located over the anterior fontanel. It is a benign and curative lesion and most of the time, can be diagnosed at birth. From 1994 to 2001, three patients were operated with this kind of lesion and after reviewing the literature we found 229 cases and only 6 cases described in Brazil. Our objective in this study is to report three more cases.<br>Cisto dermóide de inclusão congênita sobre a fontanela anterior (CDIC) é lesão rara localizada na região da fontanela anterior. Trata-se de lesão benigna e curável que, na maioria das vezes, é diagnosticada no nascimento. De 1994 a 2001, três pacientes foram operados com este tipo de lesão e, através dos dados disponíveis na literatura, verificamos somente 229 casos descritos, apenas 6 descritos no Brasil, o que nos motivou a registrar mais três casos