Silica-Alumina-Niobia (SiO2/Al2O3/Nb2O5) Matrix Obtained by the Sol-gel Processing Method: New Material for Online Extraction of Zinc Ions

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)In the present work, a new material, SiO2/Al2O3/Nb2O5 (designated as SiAlNb), was evaluated as an adsorbent in a flow injection spectrophotometric method for online preconcentration and determination of trace amounts of Zn2+ ions. The preconcentration method is based on Zn2+ adsorption onto the surface of SiAlNb in alkaline medium (pH 9.0). The elution step is carried out using HNO3 solution, followed by reaction of the Zn2+ ions with 1-(2-piridylazo)-2-naphtol (pan) in ammoniacal buffer solution (pH 9.3) containing Tween-80. The [Zn(pan)(2)] complex formed is determined at 560 nm. The method presented a linear range between 7.6 and 180.0 mu g L-1 (r = 0.9992) and limits of detection and quantification of 2.3 and 7.6 mu g L-1, respectively. According to the Langmuir linear model, the maximum adsorption capacity was found to be 7.0 mg of Zn2+ g(-1) of SiAlNb. The proposed method was successfully applied to the Zn2+ determination in water samples (lake, mineral, tap) and certified reference material (TORT-2 Lobster Hepatopancreas).21611061116Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIG)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ)IEN (Instituto de Engenharia Nuclear)Instituto Nacional de Ciencia e Tecnologia de BioanaliticaConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Self-presentation and the role of perspective taking and social motivation in autism spectrum disorder

We compared self-presentation abilities of 132 children and adolescents with autism spectrum disorders (ASD) to those of 41 typically developing (TD) peers, and examined the potential link with their social motivation and perspective taking. Participants introduced themselves to an interviewer in a baseline condition (without incentive) and a self-promotion condition (with incentive). Children with ASD (6–12 years) were just as likely as or even more likely than TD children to highlight personal characteristics that would increase their chances of obtaining the incentive. Thus, they were strategic in their self-presentation. However, adolescents with ASD (12–19 years) were less strategic than TD adolescents as well as children with ASD. We discuss the role of social motivation and perspective taking in children’s self-presentation

Maternal antibodies from mothers of children with autism alter brain growth and social behavior development in the rhesus monkey

Antibodies directed against fetal brain proteins of 37 and 73 kDa molecular weight are found in approximately 12% of mothers who have children with autism spectrum disorder (ASD), but not in mothers of typically developing children. This finding has raised the possibility that these immunoglobulin G (IgG) class antibodies cross the placenta during pregnancy and impact brain development, leading to one form of ASD. We evaluated the pathogenic potential of these antibodies by using a nonhuman primate model. IgG was isolated from mothers of children with ASD (IgG-ASD) and of typically developing children (IgG-CON). The purified IgG was administered to two groups of female rhesus monkeys (IgG-ASD; n=8 and IgG-CON; n=8) during the first and second trimesters of pregnancy. Another control group of pregnant monkeys (n=8) was untreated. Brain and behavioral development of the offspring were assessed for 2 years. Behavioral differences were first detected when the macaque mothers responded to their IgG-ASD offspring with heightened protectiveness during early development. As they matured, IgG-ASD offspring consistently deviated from species-typical social norms by more frequently approaching familiar peers. The increased approach was not reciprocated and did not lead to sustained social interactions. Even more striking, IgG-ASD offspring displayed inappropriate approach behavior to unfamiliar peers, clearly deviating from normal macaque social behavior. Longitudinal magnetic resonance imaging analyses revealed that male IgG-ASD offspring had enlarged brain volume compared with controls. White matter volume increases appeared to be driving the brain differences in the IgG-ASD offspring and these differences were most pronounced in the frontal lobes