On the effects of iron ore tailings micro/nanoparticles in embryonic and larval zebrafish (Danio rerio).

Iron ore tailings (IOT) represent a major problem in the mining industry worldwide due to large volumes of waste disposed in mine sites. IOT are exposed to the environment and subjected to wind and water dispersion, even under non-catastrophic scenarios as dam collapses, and the effects of these particles to the biota are still mostly unknown. This work aimed to prepare and to characterize a suspension containing the finest (micro/nano range) particles of IOT and to evaluate its effects on development and behavior of zebrafish (Danio rerio), at both embryonic and larval stages. IOT suspension comprised 37 mg L-1 of a multi-mineral material mainly composed by hematite and quartz, in a size-range of 33-1400 nm. Regarding in vivo toxicological assays, no robust alterations were recorded in functional, morphological and behavioral end-points analyzed, although a significant adhesion of IOT particles on zebrafish chorion was observed, without a prejudice of embryo hatching. Under applied conditions, iron ore particles did not present harmful effects to the initial stages of zebrafish development, and the particle size range and potential interactions with SiO2 content might be behind such effect.

Verificação genotípica do polimorfismo rs1143634 do gene il1b em indivíduos com a doença periodontal crônica / Genotypic Verification rs1143634 polymorphism IL1B gene in Individuals with Chronic Periodontal Disease

O objetivo desta pesquisa foi verificar a frequência do polimorfismo rs1143634 do gene IL1B em indivíduos com a doença periodontal crônica (DPC) e a relação do mesmo com o risco de afecção. Foram analisadas 39 amostras de um grupo de indivíduos diagnosticados com DPC, sendo 77% com nível leve, 21% com o nível moderado e 3% com o nível severo, apresentando uma média de idade de 43,26. Durante o estudo foram utilizadas as técnicas de PCR e RFLP para o rastreamento do SNP (Do Inglês, Single nucleotide polymorphism - Polimorfismo de Núcleotídeo Único) rs1143634, verificando-se diferenças significativas (p<0,0001) e uma redução absoluta de risco de 53,8% referente à presença do alelo C, indicando o alelo T como um fator de risco. No entanto, este resultado também sugere a possibilidade da participação de outros fatores, uma vez que a redução obtida foi pouco acima de 50%, e deste modo, poderia apontar para o envolvimento de elementos relacionados aos hábitos de vida (higiene bucal, tabagismo e etilismo) e/ou outros aspectos genéticos, considerando que o gene IL1B entre outros mediadores implicados com a patogênese da DPC possuem várias regiões polimórficas.(AU)

The current work aimed to determine the allelic frequency regarding the SNP rs1143634 in the IL1B gene of individuals with chronic periodontal disease (CPD) and the potential to predict the relative risk for the condition. Thus, 39 patients, with a mean age of 43.26, diagnosed with CPD were clinically distributed according the level of disease in low level (77%), moderate (21%), and severe (3%). In order to genotype the SNP, PCR and RFLP methodologies were used. Allele C in rs1143634 was related to an absolute relative risk reduction of 53.8%, showing statistically significant difference (p<0,0001) On the other hand, the presence of T in rs1143634 can be considered a risk factor for CPD. Additional to the results from the current study, the participation of other factors, since reduction obtained was slightly above 50%, suggested to involvement others elements including and life style (oral hygiene, smoking, and alcoholism) and the genetic risk when considering the roll of IL1B gene in the pathogenesis of CPD.(AU)