Marine Collagen/Apatite scaffolds envisaging tissue engineering applications

Despite the vast investigation and the large amount of products already available in the market to treat the different bone defects there is still a growing need to develop more advanced and complex therapeutic strategies. In this context, a mixture of Marine Hydroxyapatite-Fluorapatite:Collagen (HA-FP:ASC) seems to be a promising solution to overcome these bone defects, specifically, dental defects. HA-FP particles (20–63 μm) were obtained through pyrolysis (950°C, 12 h) of shark teeth (Isurus oxyrinchus, P. glauca), and Type I collagen was isolated from Prionace glauca skin as previously described (1). After the steps of purification, collagen was solubilized in 0.5 M acetic acid and HA-FP added producing three different formulations: were produced, 30:70, 50:50 and 70:30 of HA-FP:ASC, respectively. EDC/NHS and HMDI binding agents were used to stabilize the produced scaffolds. Mechanical properties were evaluated by compression tests. SEM analysis allowed observing the mineral deposition, after immersion in simulated body fluid and also permitted to evaluate how homogenous was the distribution of HA-FP in the different scaffold formulations, also confirmed by μ-CT assay. It was readily visible by Cytotoxicity and life/dead CLSM assays that cells were able to adhere and proliferate in the produced scaffolds. Scaffolds crosslinked with EDC/NHS showed lower cytotoxicity, being the ones chosen for further cellular evaluation.

Micro/nano-structured superhydrophobic surfaces in the biomedical field: part I: basic concepts and biomimetic approaches.

Inspired by natural structures, great attention has been devoted to the study and development of surfaces with extreme wettable properties. The meticulous study of natural systems revealed that the micro/nano-topography of the surface is critical to obtaining unique wettability features, including superhydrophobicity. However, the surface chemistry also has an important role in such surface characteristics. As the interaction of biomaterials with the biological milieu occurs at the surface of the materials, it is expected that synthetic substrates with extreme and controllable wettability ranging from superhydrophilic to superhydrophobic regimes could bring about the possibility of new investigations of cellâ material interactions on nonconventional surfaces and the development of alternative devices with biomedical utility. This first part of the review will describe in detail how proteins and cells interact with micro/nano-structured surfaces exhibiting extreme wettabilities.

[Comunicação no I Encontro de Jovens Investigadores em Ciências da Comunicação – SOPCOM]

O dia 7 de Janeiro de 2011 é uma data extraordinário para o Centro de Estudos de Comunicação e Sociedade (CECS), por duas razões principais. A primeira é porque a equipa de investigadores deste Centro – seniores e juniores – se sente, desde o seu início, profundamente comprometida com a construção da comunidade académica das Ciências da Comunicação em Portugal, a qual, como sabem, é uma comunidade jovem. A segunda é porque este vosso evento, ao qual gostosamente se associa, acabou por ser o primeiro acto dos dez anos de vida que o CECS assinala em 2011. Este Centro é, pois, ainda, uma criança, ainda que tenha já uma trajectória que fez dele uma unidade de excelência na investigação no nosso país, na nossa disciplina ou interdisciplina. Sendo um grupo jovem, é por natureza especialmente sensível à ousadia que teve o grupo organizador de vos convocar e vos acolher. Estou certo que as energias e as questões novas que o vosso grupo e os vossos debates enunciarão vão trazer uma etapa nova e promissora à SOPCOM, enriquecendo a sua agenda programática e conferindo-lhe uma vitalidade nova.

Igualdade ou algo do género... na publicidade : roteiro de boas práticas

(Excerto) Este roteiro de boas praticas na área da publicidade, cujo enfoque remete para a igualdade de género, resulta das discussões realizadas com diversos atores sociais bem como da análise de anúncios publicitários relativos a duas revistas de impacto no mercado português, no âmbito do projeto PubliDiversidade -Representações sociais e igualdade de género na publicidade da UMAR - União de Mulheres Alternativa e Resposta.

O papel dos livros informativos para a infância na conformação de uma educação histórica

Relatório de estágio de mestrado em Educação Pré-Escolar e Ensino do 1ºCiclo do Ensino Básico

Síntese de novas tieno[3,2-b]piridinas com potencial atividade biológica contendo 1,2,3-triazoles 1,4-dissubstituídos obtidos por reação "click" de ciclioadição azida-alquino catalisada por Cu(I)-CuAAC

Dissertação de mestrado em Química Medicinal

Development of a water-in-oil-in-water multiple emulsion system integrating biomimetic aqueous-core lipid nanodroplets for protein entity stabilization. Part I: experimental factorial design

Lipid nanoballoons integrating multiple emulsions of the type water-in-oil-in-water enclose, at least in theory, a biomimetic aqueous-core suitable for housing hydrophilic biomolecules such as proteins, peptides and bacteriophage particles. The research effort entertained in this paper reports a full statistical 23x31 factorial design study (three variables at two levels and one variable at three levels) to optimize biomimetic aqueous-core lipid nanoballoons for housing hydrophilic protein entities. The concentrations of protein, lipophilic and hydrophilic emulsifiers, and homogenization speed were set as the four independent variables, whereas the mean particle hydrodynamic size (HS), zeta potential (ZP) and polydispersity index (PI) were set as the dependent variables. The V23x31 factorial design constructed led to optimization of the higher (+1) and lower (-1) levels, with triplicate testing for the central (0) level, thus producing thirty three experiments and leading to selection of the optimized processing parameters as 0.015% (w/w) protein entity, 0.75% (w/w) lipophilic emulsifier (soybean lecithin) and 0.50% (w/w) hydrophilic emulsifier (poloxamer 188). In the present research effort, statistical optimization and production of protein derivatives encompassing full stabilization of their three-dimensional structure, has been attempted via housing said molecular entities within biomimetic aqueous-core lipid nanoballoons integrating a multiple (W/O/W) emulsion.