Phospholipid/cholesterol/decanethiol mixtures for direct assembly of immunosensing interfaces

In this work, a simple yet robust method to prepare lipid-based biosensing interfaces on gold using common lipids (a phospholipid and cholesterol) and an alkanethiol is reported. The lipids were carefully chosen to tailor the biophysical properties of the bilayer. The simplicity of the method relies on the incorporation of a small percentage of decanethiol in the lipid vesicles for a direct formation of a thiol-linked supported lipid bilayer, which is advantageous in several respects. It prevents the use of specially synthesized thiolipids and preserves the natural fluidity and dynamics of the lipids. As a consequence the whole arrangement is extremely stable regarding ionic strength changes and solution flow during surface plasmon resonance experiments. Moreover, we show that this interface is very effective on suppressing the nonspecific adsorption of proteins on the surface, and enables the covalent attachment of the recognition antibody. The subsequent detection of specific interaction toward antigen was monitored in real-time by SPR and confirmed by ellipsometric measurements. This lipid-based biosensing platform is versatile and can be adapted to the biorecognition reaction of interest. (C) 2015 Elsevier B.V. All rights reserved

A trajetória do Sindicato Estadual dos Profissionais da Educação do Rio de Janeiro (Sepe-RJ) na luta pela saúde no trabalho The trajectory of the State Union of Education Professionals of Rio de Janeiro (SEPE-RJ) in the struggle for workplace health

Este estudo, um dos produtos do Curso de Especialização em Saúde do Trabalhador, ano 2002, do Centro de Estudos da Saúde do Trabalhador e Ecologia Humana (CESTEH) da Escola Nacional de Saúde Pública (ENSP), Fiocruz, teve como objetivo investigar a atuação do movimento sindical na luta pela saúde no trabalho como estratégia de fortalecimento da organização e da unificação dos trabalhadores. Analisou-se a trajetória do Sindicato Estadual dos Profissionais de Educação - Sepe/RJ, de 1997 a 2002, e sua relação com a pesquisa-formação que investiga as condições de saúde e trabalho na escola pública, desenvolvida através de um grupo interinstitucional e multiprofissional envolvendo a Fundação Oswaldo Cruz, a Universidade do Estado do Rio de Janeiro, e a Universidade Federal da Paraíba, em parceria com o Sindicato Estadual dos Profissionais da Educação (Sepe-RJ) e o Sindicato de Trabalhadores da Educação do Município de João Pessoa (Sintem-PB). O estudo permite compreender que se trata de um movimento, antes de tudo, de resistência diferenciada, de renovação política de organização dos trabalhadores, podendo representar, ainda, um meio dinamizador da participação dos "trabalhadores de base", opondo-se ao cenário de fragilização sindical diante da crise do capitalismo no contexto neoliberal.<br>This study, one of the products of the Course of Specialisation in Worker's Health and Human Ecology of the Centre of Studies of Worker's Health and Human Ecology (CESTEH) of the National School of Public Health (ESNP), Oswaldo Cruz Foudation (Fiocruz) had as objective the investigation of the performance of the union movement in the fight for health at work as a strategy to enhance the organisation and unification of the workers. We analysed the trajectory of the State Union of the Education Professionals - SEPE-RJ -, from 1997 to 2000, and its relationship with a research that investigates health and work conditions of workers of education, developed by CESTEH/ENSP/Fiocruz, State University of Rio de Janeiro (UERJ), Federal University of Paraíba (UFPB), by association with SEPE-RJ and with Municipal Union of the Education Workers of João Pessoa - Paraíba (SINTEM-PB). This study shows a movement, above all, with a different resistance, with political renovation of worker’s organisation, that can still represent a dynamic place of the base participation, putting in front of the union weakness process facing the neoliberal system

Nanostructured interfaces with site-specific bioreceptors for immunosensing

In this work we propose a simple and effective approach to build nanostructured immunosensor platforms. The one-step strategy relies on i) the in situ formation of dithiocarbamates from the reaction between carbon disulfide and amine groups present on protein A ii) their attachment to gold nanopartides (AuNPs) and iii) the linkage of the modified AuNPs to the electrode surface which depends on the strong interaction between gold substrates and sulfur moieties. AuNPs and protein A are used to increase the surface coverage of Immunoglobulin G (IgG) and promote the oriented immobilization of the antibodies on the immunosensing interface. The modified gold surfaces with biomolecules were thoroughly characterized by a combination of techniques: UV-vis spectrophotometry conventional ellipsometry and atomic force microscopy. The immunosensor performance was assessed in real-time by surface plasmon resonance and by the highly sensitive total internal reflection imaging ellipsometry through the specific biorecognition between anti-IgG and the immobilized IgG molecules. We demonstrate that the presence of AuNPs improves the sensitivity of the anti-IgG specific detection whereas the presence of co-adsorbed CS2 is responsible for blocking the undesired protein nonspecific adsorption to the gold substrate. Overall we report a simple and innovative one-step method to chemically modify gold surfaces with protein A and AuNPs able to specifically detect antigen antibody interactions with capability of preventing protein nonspecific adsorption. (C) 2017 Elsevier B.V. All rights reserved.</p