Improved functionalization of oleic acid-coated iron oxide nanoparticles for biomedical applications

Superparamagnetic iron oxide nanoparticles can providemultiple benefits for biomedical applications in aqueous environments such asmagnetic separation or magnetic resonance imaging. To increase the colloidal stability and allow subsequent reactions, the introduction of hydrophilic functional groups onto the particles’ surface is essential. During this process, the original coating is exchanged by preferably covalently bonded ligands such as trialkoxysilanes. The duration of the silane exchange reaction, which commonly takes more than 24 h, is an important drawback for this approach. In this paper, we present a novel method, which introduces ultrasonication as an energy source to dramatically accelerate this process, resulting in high-quality waterdispersible nanoparticles around 10 nmin size. To prove the generic character, different functional groups were introduced on the surface including polyethylene glycol chains, carboxylic acid, amine, and thiol groups. Their colloidal stability in various aqueous buffer solutions as well as human plasma and serum was investigated to allow implementation in biomedical and sensing applications.status: publishe

A importância da equipe interdisciplinar no diagnóstico de dislexia do desenvolvimento: relato de caso The importance of interdisciplinary staff in the diagnosis of developmental dyslexia: case report

Descrevemos o trabalho de uma equipe interdisciplinar da FCM/UNICAMP na avaliação de um menino de 9 anos e 3 meses aluno de escola pública de Campinas, com dislexia do desenvolvimento. O procedimento constou de 4 fases: 1) anamnese com a mãe; 2) avaliação neuropsicológica; 3) avaliação específica de leitura e escrita; 4) exames complementares. Os resultados das várias avaliações revelaram que o menino apresenta inteligência normal, ausência de déficit auditivo ou visual mas dificuldades em provas específicas de leitura, em memória de curto prazo (especialmente em sequências auditivas) e em consciência fonológica, além de lentidão, falta de concentração, sinais neurológicos menores e hipoperfusão da porção mesial do lobo temporal. Esses dados sugeriram que a criança apresenta dislexia do desenvolvimento do tipo misto, necessitando de intervenção psicopedagógica.<br>We describe the work of the interdisciplinary staff of FCM/UNICAMP for the diagnosis of developmental dyslexia, evaluating a 9 years old boy from the second year of a first grade public school. The procedure consisted of four stages: 1) Interview with the mother (anamnesis); 2) neuropsychological evaluation; 3) specific evaluation for reading and writing skills; 4) complementary exams. The results revealed that the child presented normal intelligence, normal auditory and visual function but difficulties in reading specific test, in auditory short-term memory (specially in auditory sequences), and in phonological conscience, as well as slowness, lack of concentration, slight neurological signs and hypoperfusion of the mesial portion of the temporal lobe. These data suggest that the child has developmental dyslexia of mixed type, requiring psychopedagogic follow-up