Quality of life and place sustainability: a residents’ view

The concept of sustainability applied to the territories implies an integrated perspective considering the economic, the social, the environmental and the institutional dimensions. A vision of sustainability is nowadays crucial to the success of places, a condition in which the adoption of a Place Marketing Policy to create value and to emphasize identities is definitively interiorized by the literature. The success is achieved when the actors (citizens, visitants, business sector and all the actors that live the territory) obtain satisfaction from the territory performance and meet their expectations. A territory environmentally qualified, economically valuable, socially coherent and consistent in its heterogeneity, where the local agents are active participants and not spectators of the territory changes represents the objectives and the crucial condition for the development of a strategic marketing policy destination. A theoretical framework based on the contributions of Breakwell (1992, 1993), Hidalgo and Hernandez (2001), Twigger-Ross and Uzzell (1996) was developed and applied to Portimão a city located on south-western Algarve, Portugal. The study aims to describe and understand the causal relations between independent variables (individual characteristics, residential time and quality of life attributes) and dependent measures (place attachment and place-related identity)

Layer-by-layer assembly of chitosan and recombinant biopolymers into biomimetic coatings with multiple stimuli-responsive properties

In this work, biomimetic smart thin coatings using chitosan and a recombinant elastin-like recombinamer (ELR) containing the cell attachment sequence arginine–glycine–(aspartic acid) (RGD) are fabricated through a layer-by-layer approach. The synthetic polymer is characterized for its molecular mass and composition using mass spectroscopy and peptide sequencing. The adsorption of each polymeric layer is followed in situ at room temperature and pH 5.5 using a quartz-crystal microbalance with dissipation monitoring, showing that both polymers can be successfully combined to conceive nanostructured, multilayered coatings. The smart properties of the coatings are tested for their wettability by contact angle (CA) measurements as a function of external stimuli, namely temperature, pH, and ionic strength. Wettability transitions are observed from a moderate hydrophobic surface (CAs approximately from 62° to 71°) to an extremely wettable one (CA considered as 0°) as the temperature, pH, and ionic strength are raised above 50 °C, 11, and 1.25 m, respectively. Atomic force microscopy is performed at pH 7.4 and pH 11 to assess the coating topography. In the latter, the results reveal the formation of large and compact structures upon the aggregation of ELRs at the surface, which increase water affinity. Cell adhesion tests are conducted using a SaOs-2 cell line. Enhanced cell adhesion is observed in the coatings, as compared to a coating with a chitosan-ending film and a scrambled arginine–(aspartic acid)–glycine (RDG) biopolymer. The results suggest that such films could be used in the future as smart biomimetic coatings of biomaterials for different biomedical applications, including those in tissue engineering or in controlled delivery systems.EUJCyL - VA034A09, VA030A08Fundação para a Ciência e Tecnologia (FCT) - SFRH/BD/61126/2009, SFRH/BD/61390/2009MICINN - MAT 2007-66275-C02-01, MAT 2007-61604, MAT 2009-14195-C03-03, PSE-300100-2006-1European regional development fund (ERDF)Junta de Castilla y LeonNetwork Center of Regenerative Medicine and Cellular Therapy of Castilla and LeónCIBER-BBN (project CB06-01-0003

High-throughput evaluation of interactions between biomaterials, proteins and cells using patterned superhydrophobic substrates

We propose a new low cost platform for high-throughput analysis that permits screening the biological performance of independent combinations of biomaterials, cells and culture media. Patterned superhydrophobic flat substrates with controlled wettable spots are used to produce microarray chips for accelerated multiplexing evaluation.This work was partially supported by Fundação para a Ciência e Tecnologia (FCT) under project PTDC/FIS/68517/2006

Immobilization of biomolecules on chitosan surface for selective recruitment, controlled growth and differentiation of cells from mixed populations

info:eu-repo/semantics/publishedVersio

Chitosan membranes for spatially controlled cell adhesion and specific cell recruitment

We propose a concept of biomaterials that are able to fix specific cell types onto their surface when in contact with a mix population of cells. Adipose tissue has shown to be an interesting source of stem cells with therapeutic potential. However only a small amount of the heteroge- neous mixture of the cells extracted from lipoaspirates are stem cells, and within stem cells there are different populations with different capabilities to differentiate through a lineage. We studied the ability of immobilized antibodies on chitosan surfaces to capture specific types of cells with a spatial micrometer resolution.Antibodies were covalently immobilized onto chitosan membranes using bis[sulfosuccinimidyl] su- berate (BS3). X-ray photoelectron spectroscopy (XPS) was used to chemically characterize the surface and quartz crystal microbalance (QCM) to calculate the amount of adsorbed and/or immobilized anti- body. Data shown greater immobilization when BS3 was used com- pared to simple adsorption. Specific antibodies covalently immobilized in a surface, kept their bioactivity and controlled the type of cell that attached on the chitosan surface. Microcontact printing permitted to covalently immobilize antibodies in patterns allowing a spatial control in cell attachment. Cell sorting experiments performed using a mixture of adipose stem cells and osteoblast like cells shown that chitosan sur- faces were able to capture a specific phenotype depending on the immobilized antibody

Functional chitosan microcarriers for selective cell attachment and expansion

The success of many stem cell applications in the biomedical field is highly dependent on the development of reliable techniques either for isolation or selection of specific cell populations with a very high yield and purity.1 In this work we propose the use of chitosan microparticles (μPs) to capture a specific cell type based in the concept of antibody-antigen binding. Our goal was to create new biomaterials capable of selecting within a heterotypic cell suspension, a specific sub-population, and supporting subsequent cell expansion. Such system simultaneously allows the selection and acts as a microcarrier for a specific target, thus reducing cell manipulation and time-consumption

Functional cell microcarriers: a new platform for cell separation and expansion

Publicado em "Journal of Tissue Engineering and Regenerative Medicine", vol. 7, supp. 1 (2013)The success of many stem cell applications in the biomedical field is highly dependent on the development of separation techniques for isolation and purification of cells with a very high yield and purity. Despite all the achievements made in the field over the past several years, new systems for effective cell separation are still needed. Previous work from our group demonstrated that functional chitosan films grafted with antibodies promote selective cell adhesion. 1 Herein we developed chitosan microparticles able to capture a specific cell types based in the concept of antibody coating for cell sorting. Our goal was to create new biomaterial surfaces capable of recruit a specific cell population within a mixture, reducing cell manipulation and time-consuming allowing at the same time cell expansion. Such system acts as a microcarrier for cell expansion of a specific cell target. Microcarrier culture system offers the advantage of providing a larger surface area for the growth of anchorage-dependent cells in a suspension culture system. Chitosan was chosen due to the excellent biocompatibility, gel forming properties, chemistry surface and low cell adhesion. This allows the modification with specific biochemical cues, for a controllable cell attachment. Here we develop functional biotinylated microparticles, such system allows tailoring microparticles to a variety of functional biomolecules. Here we tested the immobilization of antibodies to target specific cell types, CD31 for endothelial cells and CD90 for adipose stem cells. Primarily designed for an application in tissue engineering, two main challenges are accomplished with the herein presented microparticles: separation and scale-up expansion of specific cell type. The herein developed polymeric microparticles can also be used for directly deliver cells in vivo to repair and regenerate tissues

Animal protein-based soft materials for tissue engineering applications

Proteins have long been used in coatings for cell culture plates and to supplement cell culture media. Due to their unmatched biocompatibility, biodegradability, bioactivity and immune-privilege, the interest in proteins rapidly advanced for the design and engineering of more complex substrates for biomedical applications. In this chapter, the proteins typically used in the design and fabrication of biomedical devices are presented and discussed, with particular focus in human-based platforms. However, restrictions in the use of protein-derived materials are associated with their limited processability and stability, but to overcome this, multiple bioconjugation techniques have been described and are herein presented. An overview of current protein-based materials that have found clinical application and that have been commercialized is also provided.publishe

Selective cell recruitment and spatially controlled cell attachment on instructive chitosan surfaces functionalized with antibodies

Bioactive constructs to guide cellular mobilization and function have been proposed as an approach for a new generation of biomaterials in functional tissue engineering. Adult mesenchymal stem cells have been widely used as a source for cell based therapeutic strategies, namely tissue engineering. This is a heterogeneous cell population containing many subpopulations with distinct regenerative capacity. Thus, one of the issues for the effective clinical use of stem cells in tissue engineering is the isolation of a highly purified, expandable specific subpopulation of stem cells. Antibody functionalized biomaterials could be promising candidates to isolate and recruit specific cell types. Here we propose a new concept of instructive biomaterials that are able to recruit and purify specific cell types from a mixed cell population. This biomimetic concept uses a target-specific chitosan substrate to capture specific adipose derived stem cells. Specific antibodies were covalently immobilized onto chitosan membranes using bis[sulfosuccinimidyl] suberate (BS3). Quartz crystal microbalance (QCM) was used to monitor antibody immobilization/adsorption onto the chitosan films. Specific antibodies covalently immobilized kept their bioactivity and captured specific cell types from a mixed cell population. Microcontact printing allowed to covalently immobilize antibodies in patterns and simultaneously a spatial control in cell attachmentThe authors acknowledge the Portuguese Foundation for Science and Technology (FCT) for the fellowships SFRH/BD/61390/2009 (C.A.C) and SFRH/BPD/45206/2008 (A.M.F), and also to the International Max-Planck-Research School (C.A.C) for the financial support. We are grateful to Hospital da Prelada for the donations. This work was carried out under the scope of the EU 7th Framework Programme (FP7/2007-2013) under grant agreement no. NMP4-SL-2009-229292 (Find&Bind)