Interaction between acrylic substrates and RAD16-I peptide in its self-assembling

[EN] Self-assembling peptides (SAP) are widely used as scaffolds themselves, and recently as fillers of microporous scaffolds, where the former provides a cell-friendly nanoenvironment and the latter improves its mechanical properties. The characterization of the interaction between these short peptides and the scaffold material is crucial to assess the potential of such a combined system. In this work, the interaction between poly(ethyl acrylate) (PEA) and 90/10 ethyl acrylate-acrylic acid copolymer P(EAcoAAc) with the SAP RAD16-I has been followed using a bidimensional simplified model. By means of the techniques of choice (congo red staining, atomic force microscopy (AFM), and contact angle measurements) the interaction and self-assembly of the peptide has proven to be very sensitive to the wettability and electro-negativity of the polymeric substrate.The authors acknowledge funding through the European Commission FP7 project RECATABI (NMP3-SL-2009-229239), and from the Spanish Ministerio de Ciencia e Innovacion through projects MAT2011-28791-C03-02 and -03. This work was also supported by the Spanish Ministerio de Educacion through M. Arnal-Pastor FPU 2009-1870 grant. The authors acknowledge the assistance and advice of Electron Microscopy Service of the UPV.Arnal Pastor, MP.; González-Mora, D.; García-Torres, F.; Monleón Pradas, M.; Vallés Lluch, A. (2016). Interaction between acrylic substrates and RAD16-I peptide in its self-assembling. 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Implementation of the evidence for the improvement of nursing care to the critical patient's family: a participatory action research

Background: There are many descriptive studies regarding the needs of the family, as well as those regarding nursing care aimed directly at family members. However, there is no widespread application of such evidence in clinical practice. There has also been no analysis made of the evolution of patterns of knowing during the act of improving clinical practice. Therefore, the purpose of the study is to understand the change process aimed at improving care to critical patient's families, and to explore the evolution of patterns of knowing that nurses use in this process. Methods: Qualitative study with a Participatory Action Research method, in accordance with the Kemmis and McTaggart model. In this model, nurses can observe their practice, reflect upon it and compare it with scientific evidence, as well as define, deploy and evaluate improvement strategies adapted to the context. Simultaneously, the process of empowerment derived from the Participatory Action Research allows for the identification of patterns of knowing and their development over time. The research will take place in the Intensive Care Units of a tertiary hospital. The participants will be nurses who are part of the regular workforce of these units, with more than five years of experience in critical patients, and who are motivated to consider and critique their practice. Data collection will take place through participant observation, multi-level discussion group meetings and documentary analysis. A content analysis will be carried out, following a process of codification and categorisation, with the help of Nvivo10. The approval date and the beginning of the funding were December 2012 and 2013, respectively. Discussion: The definition, introduction and evaluation of care strategies for family members will allow for their real and immediate implementation in practice. The study of the patterns of knowing in the Participatory Action Research will be part of the theoretical and practical feedback process of a professional discipline. Also, the identification of the construction and evolution of knowledge will provide decision elements to managers and academics when choosing strategies for increased quality

Volume mesh generation and finite element analysis of trabecular bone magnetic resonance images

In order to help the assessment of trabecular bone diseases and complement dual X-Ray absorptiometry (DXA) in diagnosis process, it is needed an accurate mechanical characterization of trabecular bone structure to estimate the risk of fracture and evaluate micro-architecture deterioration. As Finite Element modeling has become a well-established method for analysis of complex structures, an algorithm has been developed to build a Finite Element mesh from three-dimensional reconstruction information in voxels. Generated mesh is loaded in a finite element analysis software in order to simulate micro-architecture mechanical behavior under compression conditions. Most part of related researches have been based on ex vivo micro-computed tomography (muCT) scans. This study uses three-dimensional trabecular bone reconstructions from high resolution magnetic resonance images acquired in vivo

Implementation of evidence on the nurse-patient relationship in psychiatric wards through a mixed method design: study protocol

Background: Psychiatric nurses are aware of the importance of the therapeutic relationship in psychiatric units. Nevertheless, a review of the scientific evidence indicates that theoretical knowledge alone is insufficient to establish an adequate therapeutic alliance. Therefore, strategies are required to promote changes to enhance the establishment of the working relationship. The aims of the study are to generate changes in how nurses establish the therapeutic relationship in acute psychiatric units, based on participative action research and to evaluate the effectiveness of the implementation of evidence through this method. Methods/Design: The study will use a mixed method design. Qualitative methodology, through participative action research, will be employed to implement scientific evidence on the therapeutic relationship. A quasi-experimental, one-group, pre-test/post-test design will also be used to quantitatively measure the effectiveness of the implementation of the evidence. Participants will consist of nurses and patients from two psychiatric units in Barcelona. Nurses will be selected by theoretical sampling, and patients assigned to each nurses will be selected by consecutive sampling. Qualitative data will be gathered through discussion groups and field diaries. Quantitative data will be collected through the Working Alliance Inventory and the Interpersonal Reactivity Index. Qualitative data will be analysed through the technique of content analysis and quantitative data through descriptive and inferential statistics. Discussion: This study will help to understand the process of change in a nursing team working in an inpatient psychiatric ward and will allow nurses to generate knowledge, identify difficulties, and establish strategies to implement change, as well as to assess whether the quality of the care they provide shows a qualitative improvement.This study is funded by the College of Nurses of Barcelona as part of the Research Projects Grants (PR- 1915-14/2014)