Detecção de autoanticorpos antifosfolipides por adsorção de afinidade utilizando magenetolipossomas

Orientadores: Maria Helena Andrade Santana, Ricardo de Lima ZollnerDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia QuimicaResumo: O encapsulamento de ferrofluidos no núcleo de lipossomas origina vesículas denominadas magnetolipossomas, que podem ser eficientemente separadas da solução quando sob a ação de um campo magnético de alto gradiente. Essa propriedade possibilita a aplicação dos magnetolipossomas como adsorventes específicos em processos de separação de estruturas como células e biomoléculas. A maior vantagem desta abordagem é a simplicidade e eficiência. Anticorpos antifosfolípides constituem uma importante classe de biomoléculas, para a qual fosfolipídios específicos podem ser usados como ligantes de afinidade. A incorporação desses fosfolipídios na matriz estrutural dos lipossomas produz suportes coloidais de elevada área específica, com sítios de afinidade sobre a superficie, que são úteis para aplicação em processos de separação e detecção dessa classe de anticorpos. Os autoanticorpos estão presentes no soro de pacientes portadores de doenças autoimunes e a sua detecção apresenta dificuldades no que diz respeito à reprodutibilidade e à variabilidade dos suportes usados em kits comercialmente disponíveis. A adsorção específica de autoanticorpos na superficie dos magnetolipossomas e o desenvolvimento de sinal magnético resultante da ligação constitui técnica alternativa promissora para o diagnóstico de autoanticorpos. As vantagens do novo método seriam a reprodutibilidade, versatilidade do suporte e a condução do ensaio em etapa única. O objetivo deste trabalho foi o estudo da preparação e caracterização de magnetolipossomas de afinidade, além da avaliação do desempenho desses suportes na ligação dos autoanticorpos. Na preparação dos magnetolipossomas, foi usada magnetita coloidal como ferrofluido, cardiolipina, fosfatidiletanolamina e fosfatidilserina como lipídios de afinidade e fosfatidilcolina como lipídio estrutural. A adsorção dos anticorpos na superficie dos magnetolipossomas foi estudada em mistura e de modo frontal em coluna capilar. Como resultado da preparação das partículas obteve-se associação adequada entre a magnetita e os fosfolipídios, reprodutibilidade e boa estabilidade. Em relação à adsorção dos anticorpos observou-se que há especificidade, demonstrando a potencialidade de utilização dos magnetolipossomas no desenvolvimento de uma nova técnica de detecção de autoanticorpos antifosfolípidesAbstract: The entrapment of ferrofluids into the core of liposomes provides vesic1es called magnetoliposomes, which can be efficient1y captured ITom a solution under the action of a high gradient magnetic field. Due to this property, it is possible the aplication of magnetoliposomes as specific adsorbents in separation processes of structures like cells and biomolecules. The main advantage of this approach is its simplicity and efficiency. Antiphospholipid antibodies are an important c1ass of biomolecules, to whom specific phospholipids can be used as affinity ligands. The aggregation of these phospholipids in the structural matrix of the liposomes produces co1110idal supports with high specific surface area, with affinity sites on the surface, which are useful for applications in separation processes and detection of this antibody c1ass. They are present in the sera of patients with autoimmune diseases, and their detection presents difficulties in respect to the reprodutibilty of results, due to the heterogeneity of the molecules in this group. In addition, there is the multi-step characteristic of the ELISA assay, the most commonly used, and the variability of the supports in the available commercial kits. The specific antibody adsorption on the surface of magnetoliposomes and the development of a magnetic signal due to the linking is an alternative technique for the autoantibody diagnostico The advantages of the new method would be the reprodutibility, versatility of the supports and a single-step assay. The aim of this work was the preparation and characterization of affinity magnetoliposomes, and the evaluation of their performance in the interaction with autoantibodies. In their preparation colloidal magnetite was used as ferrofluid, cardiolipin, serine and ethanolamine as affinity lipids and choline as the structural one. The antibody adsorption was studied in batch and plug-flow mode in capilar column. As a result of the preparation, we obtained reprodutibility, and as for the adsorption, we observed that there is a good potentiality to use magnetoliposomes in the development of a detection technique of antiphospholipid antibodiesMestradoDesenvolvimento de Processos BiotecnologicosMestre em Engenharia Químic

Characterization, physicochemical stability, and evaluation of in vitro digestibility of solid lipid microparticles produced with palm kernel oil and tristearin

Solid lipid particles have been investigated by food researchers due to their ability to enhance the incorporation and bioavailability of lipophilic bioactives in aqueous formulations. The objectives of this study were to evaluate the physicochemical stability and digestibility of lipid microparticles produced with tristearin and palm kernel oil. The motivation for conducting this study was the fact that mixing lipids can prevent the expulsion of the bioactive from the lipid core and enhance the digestibility of lipid structures. The lipid microparticles containing different palm kernel oil contents were stable after 60 days of storage according to the particle size and zeta potential data. Their calorimetric behavior indicated that they were composed of a very heterogeneous lipid matrix. Lipid microparticles were stable under various conditions of ionic strength, sugar concentration, temperature, and pH. Digestibility assays indicated no differences in the release of free fatty acids, which was approximately 30% in all analises. The in vitro digestibility tests showed that the amount of palm kernel in the particles did not affect the percentage of lipolysis, probably due to the high amount of surfactants used and/or the solid state of the microparticles.The authors are grateful to the FAPESP and CNPq for the scholarships granted (J.C.S., FAPESP fellowships 2010/13229-8 and 2012/02316-2, and T. R. B, FAPESP fellowship 2010/15031-0) and to Agropalma S/A for their generous palm kernel oil donation. Author Ana C. Pinheiro gratefully acknowledges the fellowship (SFRH/BD/48120/2008) granted by the Fundacao para a Ciencia e Tecnologia (FCT, Portugal)

Physico-chemical stability and in vitro digestibility of beta-carotene-loaded lipid nanoparticles of cupuacu butter (Theobroma grandiflorum) produced by the phase inversion temperature (PIT) method

Beta-carotene is a carotenoid with a wide spectrum of biological activities (e.g., anti-cancer, anti-hypertensive, and anti-inflammatory). However, because of its extremely high hydrophobicity, it is difficult to incorporate in food formulations and its bioavailability is fairly low. Lipid-based encapsulation colloidal systems such as lipid nanoparticles can help overcome these issues. In this study, beta-carotene-loaded lipid nanoparticles were produced by the phase inversion temperature (PIT) method from 10% cupuacu butter and 20% surfactant (Cremophor RH40 and Span 80). The inversion temperature of the nanoparticles was 74 °C and their average diameter was 35 nm. After 100 days of storage, 85% of the initial amount of beta-carotene remained in the nanoparticles; alpha-tocopherol was found to be essential for carotenoid preservation. Comparison of the results of in vitro digestion between static and dynamic systems was performed, and the characteristics of each digestion system led to diverse results in terms of average particle size and beta-carotene bioaccessibility. Although the static system was much simpler than the dynamic system, it could not provide reliable data of the digestibility of the lipid nanoparticles. The bioaccessibility of beta-carotene in the static system was 92%, very similar to the results found in the literature; by comparison, the dynamic system revealed a beta-carotene bioaccessibility of nearly 20%. Despite this discrepancy, the highly realistic conditions of digestion simulated by the dynamic in vitro system indicate that the results of this system are more reliable than those obtained from the simplified static system applied in this research.The authors thank FAPESP (Fundação de Amparo à Pesquisa do Estado de São Paulo, Brazil) for the fellowships (grants 2010/20523-0, 2011/01260-0 and 2012/18495-3, authors Graziela V.L. Gomes and Mirella R. Sola). The author Ana C. Pinheiro is recipient of a fellowship from the Fundação para a Ciência e Tecnologia (FCT, Portugal) through grant SFRH/BPD/101181/2014

Ações do Grupo de Apoio Pedagógico (GAP) em prol do ensino de graduação da Faculdade de Zootecnia e Engenharia de Alimentos (FZEA)

This report presents the activities performed by GAP-FZEA during the period of 2005 to 2016 and their impact on the occupation of FZEA teachers in relation to teaching/learning process. Before the creation of Course Coordinating Committees (CoCs), the GAP-FZEA helped the FZEA teachers to draw the professional profile of Higher Education students and also helped them to think about their own pedagogical formation. After the CoCs creation, besides the GAP-FZEA was continuing to work in direction to pedagogical formation of the teachers, they mainly focus on helping the CoCs of FZEA in thinking about the construction of PoliticalPedagogical Project (PPP). Later, the GAP-FZEA promoted the I Simpósio de Graduação da FZEA, which give to teachers the opportunity to exchange experiences regarding to pedagogical management and practice. The GAP-FZEA provides favorable conditions to congregate the teachers by stimulating the discussion about teaching/learning process.O presente relato apresenta as ações exercidas pelo GAP-FZEA durante o período de 2005 a 2016 e o seu impacto nas atividades desenvolvidas pelos docentes da FZEA pertinentes ao ensino de graduação. Antes da criação das Comissões Coordenadoras de Curso (CoCs), o GAP-FZEA atuou diretamente na promoção de eventos sobre gestão pedagógica dando subsídios aos docentes para que os mesmos refletissem sobre a necessidade de traçar o perfil profissional do estudante e sobre sua própria formação pedagógica. Após a criação das CoCs, o GAPFZEA, além de continuar trabalhando na formação pedagógica dos docentes da FZEA, atuou indiretamente na gestão pedagógica dando subsídios às CoCs da FZEA para que as mesmas reflitam sobre a construção dos Projetos Políticos Pedagógicos (PPPs). Posteriormente, o GAP-FZEA promoveu o I Simpósio de Graduação da FZEA, que permitiu a troca de experiências vivenciadas pelos docentes da FZEA quanto à gestão e à prática pedagógica. O GAP-FZEA mostrou que pode propiciar espaços para congregar os docentes e estimular o debate sobre as práticas de ensino-aprendizagem na construção desse ambiente de aprimoramento

TRY plant trait database – enhanced coverage and open access

Plant traits - the morphological, anatomical, physiological, biochemical and phenological characteristics of plants - determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait‐based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits - almost complete coverage for ‘plant growth form’. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait–environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives

Erratum: Global, regional, and national comparative risk assessment of 84 behavioural, environmental and occupational, and metabolic risks or clusters of risks for 195 countries and territories, 1990–2017: a systematic analysis for the Global Burden of Disease Study 2017

Interpretation: By quantifying levels and trends in exposures to risk factors and the resulting disease burden, this assessment offers insight into where past policy and programme efforts might have been successful and highlights current priorities for public health action. Decreases in behavioural, environmental, and occupational risks have largely offset the effects of population growth and ageing, in relation to trends in absolute burden. Conversely, the combination of increasing metabolic risks and population ageing will probably continue to drive the increasing trends in non-communicable diseases at the global level, which presents both a public health challenge and opportunity. We see considerable spatiotemporal heterogeneity in levels of risk exposure and risk-attributable burden. Although levels of development underlie some of this heterogeneity, O/E ratios show risks for which countries are overperforming or underperforming relative to their level of development. As such, these ratios provide a benchmarking tool to help to focus local decision making. Our findings reinforce the importance of both risk exposure monitoring and epidemiological research to assess causal connections between risks and health outcomes, and they highlight the usefulness of the GBD study in synthesising data to draw comprehensive and robust conclusions that help to inform good policy and strategic health planning