792 research outputs found

    Collagens from marine organisms towards biomedical applications

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    [Excerpt] Collagen is the main fibrous structural protein in the extracellular matrix and connective tissue of animals. It is a primary building block of bones, tendons, skin, hair, nails, cartilage, and all joints in the body. It is also considered a "glue" that holds the body together. In this regard, it receives great attention in healthcare and wellbeing, both as a functional ingredient in different formulations and as a component of several products, such as medical devices and pharmaceutical systems

    Quark matter revisited with non extensive MIT bag model

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    In this work we revisit the MIT bag model to describe quark matter within both the usual Fermi-Dirac and the Tsallis statistics. We verify the effects of the non-additivity of the latter by analysing two different pictures: the first order phase transition of the QCD phase diagram and stellar matter properties. While, the QCD phase diagram is visually affected by the Tsallis statistics, the resulting effects on quark star macroscopic properties are barely noticed.Comment: 10 pagens, 5 figure

    In vivo skin hydrating efficacy of fish collagen from greenland halibut as a high-value active ingredient for cosmetic applications

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    The industrial processing of fish for food purposes also generates a considerable number of by-products such as viscera, bones, scales, and skin. From a value-added perspective, fish by-products can act also as raw materials, especially because of their collagen content (particularly in fish skin). Interestingly, the potential of marine collagen for cosmetic applications is enormous and, remarkably, the extraction of this protein from fish skins has been established for different species. Using this approach, we investigated the integration of marine collagen (COLRp_I) extracted from the skin of the Greenland halibut as an active ingredient in a cosmetic hydrogel formulation. In this study, extracts of marine collagen at concentrations up to 10 mg/mL showed a non-cytotoxic effect when cultured with fibroblast cells for 3 days. In addition, marine collagen extract, when incorporated into a cosmetic hydrogel formulation, met criterion A of ISO 11930:2019 regarding the efficacy of the preservative system (challenge test). In addition, the cosmetic formulations based on marine collagen at dosages of 0.1, 0.25 and 0.5% were tested in a clinical study on the skin of the forearms of 23 healthy volunteers, showing a sightly hydration effect, suggesting its potential for beauty applications. Moreover, this work illustrates that the circular economy concept applied to the fish processing industry can represent important benefits, at innovation, environmental and economic levels.The authors acknowledge the funding from the European Union Transborder Cooperation Programme Interreg España-Portugal 2014–2020 (POCTEP) under the project 0302_CVMAR_I_1_P, which supported also the cosmetic clinical study performed by INOVAPOTEK under a services acquisition contract

    Extraction and characterization of collagen from elasmobranch byproducts for potential biomaterial use

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    With the worldwide increase of fisheries, fish wastes have had a similar increase, alternatively they can be seen as a source of novel substances for the improvement of societyâ s wellbeing. Elasmobranchs are a subclass fished in high amounts, with some species being mainly bycatch. They possess an endoskeleton composed mainly by cartilage, from which chondroitin sulfate is currently obtained. Their use as a viable source for extraction of type II collagen has been hypothesized with the envisaging of a biomedical application, namely in biomaterials production. In the present work, raw cartilage from shark (Prionace glauca) and ray (Zeachara chilensis and Bathyraja brachyurops) was obtained from a fish processing company and submitted to acidic and enzymatic extractions, to produce acid-soluble collagen (ASC) and pepsin-soluble collagen (PSC). From all the extractions, P. glauca PSC had the highest yield (3.5%), followed by ray ASC (0.92%), ray PSC (0.50%), and P. glauca ASC (0.15%). All the extracts showed similar properties, with the SDS-PAGE profiles being compatible with the presence of both type I and type II collagens. Moreover, the collagen extracts exhibited the competence to maintain their conformation at human basal temperature, presenting a denaturation temperature higher than 3 C. Hydrogels were produced using P. glauca PSC combined with shark chondroitin sulfate, with the objective of mimicking the human cartilage extracellular matrix. These hydrogels were cohesive and structurally-stable at 37 C, with rheological measurements exhibiting a conformation of an elastic solid when submitted to shear strain with a frequency up to 4 Hz. This work revealed a sustainable strategy for the valorization of fisheriesâ by-products, within the concept of a circular economy, consisting of the use of P. glauca, Z. chilensis, and B. brachyurops cartilage for the extraction of collagen, which would be further employed in the development of hydrogels as a proof of concept of its biotechnological potential, ultimately envisaging its use in marine biomaterials to regenerate damaged cartilaginous tissues.The authors acknowledge the fish-processing industry Nigel (Peniche, Portugal) for the kind offer of shark and ray by-products, Marco Lemos (MARE-Leiria, IPLeiria, Portugal) for valuable discussions, and Filipe Costa and Sofia Duarte (CBMA, University of Minho, Portugal) for the DNA barcoding analysis for identification/confirmation of elasmobranchii species

    Comparison of the start, turn and finish performance of elite swimmers in 100 m and 200 m races

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    The main aim of this study was to compare the start, turn, and finish performance of 100 m and 200 m events in the four swimming strokes in elite swimmers of both sexes. The performances of all 128 finalists (64 males and 64 females) of the 100 m, and 200 m events at a major championship were analyzed. A set of variables related to the start, turn, and finish were assessed. In the start a significant and moderate race effect was verified in both sexes (100 m vs 200 m). It was highest in butterfly events (males: Δ = 9.81%, p = 0.046, η2 = 0.60; females: Δ = 7.96%, p < 0.001, η2 = 0.75). In the turn a significant and moderate-strong race effect was verified in all strokes in both sexes, the highest being in butterfly (males: Δ = 12.26%, p < 0.001, η2 = 0.93; females: Δ = 10.74%, p < 0.001, η2 = 0.92). The finish had a significant and moderate race effect in butterfly and in breaststroke (females). The underwater variables were found to be the main contributors to a faster start. Over the turn, key determinants were the surface variables. As for the finish, mixed results were observed. It can be suggested that the underwater profile was the main determinant in starting, whereas the surface profile was the main determinant in turning. Therefore, coaches are advised to focus on such race phases to enhance the total race time.Our thanks to LEN and Spiideo AB for providing the video clips. This work is supported by national funding through the Portuguese Foundation for Science and Technology, I.P., under project UIDB/04045/2020. We would also like to thank the University of Beira Interior and Santander Universities (Bolsa BIPD/ICIFCSH-Santander Universidades-UBI/2017) for their support. The experiments comply with the current laws of the country in which they were performed. The authors have no conflict of interest to declare.info:eu-repo/semantics/publishedVersio

    Chondrosia reniformis marine-sponge collagen membranes for skin re-epithelialization

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    Chondrosia reniformis collagen has been identified as mainly of type IV. Being collagen IV the main component of the epidermal basal layer [1], C. reniformis represents a valuable source to be explored in the skin regeneration field. This work envisaged the production of C. reniformis collagen membranes for the selection of rapidly adherent epidermal cells, like the commercial collagen coatings, and for their subsequent culture. This approach would permit a single system for culturing and carrying basal epidermal cells aimed at re-epithelialize skin wounds. Materials and Methods The collagen of C. reniformis marine-sponge was extracted with 100mM Tris-HCl, 10mM EDTA, 8M urea and 100mM 2-mercaptoethanol. To define the best re-solubilization conditions, the obtained precipitate was dissolved in five different solutions: Solution A: 100mM Tris-HCl+8M Urea+10mM EDTA (pH 9.5); Solution B: 50mM Tris-HCl+1M NaCl (pH 7.4); Solution C: 100mM Tris-HCl (pH 7.4); Solution D: 0.5% H2O2 (v/v) (pH 11) and Solution E: 100mM Tris-HCl (pH 9.5). Solutions of 1% collagen were prepared and cross-linking was performed with HMDI, genipin and EDC/NHS at different concentrations. The membranes were obtained by solvent-casting and/or freeze-drying, and their stability was tested both in PBS and culture medium, for at least 7 days. Morphological characterization of the membranes was carried out by scanning electron microscopy (SEM). Cytotoxicity, based on metabolic activity (MTS assay) and cell proliferation (DNA quantification) analysis of the 100mM Tris-HCl (pH 9.5) and 8mM EDC/NHS cross-linked collagen membranes, was assessed with L929 cells. Results were analyzed by IBM SPSS Statistics Version 20 using one-way ANOVA and Kruskall-Wallis test. Significance was set for

    Análise dos Fatos utilizados no 13º Campeonato do Mundo FINA

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    Para nadar mais rápido, é necessário aumentar a propulsão e diminuir o arrasto. Para o caso, os fatos de natação de poliuretano podem ter desempenhado um papel importante (Marinho et al., 2009). Com este estudo pretende-se descrever a distribuição dos diferentes modelos de fatos de natação usados pelos nadadores durante todas as finais do 13º Campeonato do Mundo de natação, realizado em Roma e assim perceber as preferências dos nadadores de elevado nível desportivo

    Nanostructured natural-based polyelectrolyte multilayers to agglomerate chitosan particles into scaffolds for tissue engineering

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    The Layer-by-Layer (LbL) deposition technique is a self-assembly process that allows the coating of material's surface with nanostructured layers of polyelectrolytes, allowing to control several surface properties. This technique presents some advantages when compared with other thin film assembly techniques like having the possibility to coat surfaces with complex geometries in mild conditions or to incorporate active compounds. Tissue engineering involves typically the use of porous biodegradable scaffolds for the temporary support of cells. Such structures can be produced by agglomeration of micro-spheres that needs to be fixed into a three dimensional structure. In this work we suggest the use of LbL to promote such mechanical fixation in free-formed micro-spheres assemblies and simultaneously to control the properties of its surface. For the proof of concept the biological performance of chitosan/alginate multilayers is first investigated in two-dimensional models in which the attachment and proliferation of L929 and ATDC5 cells are studied in function of the number of layers and the nature of the final layer. Scaffolds prepared by agglomeration of chitosan particles using the same multilayered system were processed and characterized; it was found that they could support the attachment and proliferation of ATDC5 cells. This study suggests that LbL can be used as a versatile methodology to prepare scaffolds by particle agglomeration that could be suitable for tissue engineering applications.Fundo Europeu de Desenvolvimento Regional (FEDER) através do Programa Operacional de Cooperação Transfronteiriça Espanha Portugal 2007-2013 (POCTEP)Fundação para a Ciência e a Tecnologia (FCT

    Fucoidan-based hydrogels particles as versatile carriers for diabetes treatment strategies

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    There is a current lack of fully efficient therapies for diabetes mel-litus, a chronic disease where the metabolism of blood glucose isseverely hindered by a deficit in insulin or cell resistance to thishormone. Therefore, it is crucial to develop new therapeutic strat-egies to treat this disease, including devices for the controlleddelivery of insulin or encapsulation of insulin-producing cells. Inthis work, fucoidan (Fu)â a marine sulfated polysaccharide exhib-iting relevant properties on reducing blood glucose and antioxi-dant and anti-inflammatory effectsâ was used for thedevelopment of versatile carriers envisaging diabetes advancedtherapies. Fu was functionalized by methacrylation (MFu) using8% and 12% (v/v) of methacrylic anhydride and further photo-crosslinked using visible light in the presence of triethanolamineand eosin-y to produce hydrogel particles. Degree of methacryla-tion varied between 2.78 and 6.50, as determined by1HNMR, andthe produced particles have an average diameter ranging from0.63 to 1.3mm (dry state). Insulin (5%) was added to MFu solutionto produce drug-loaded particles and the release profile wasassessed in phosphate buffer solution (PBS) and simulated intes-tinal fluid (SIF) for 24h. Insulin was released in a sustained man-ner during the initial 8 h, reaching then a plateau, higher in PBSthan in SIF, indicating that lower pH favors drug liberation.Moreover, the ability of MFu particles to serve as templates forthe culture of human pancreatic cells was assessed using 1.1B4cell line during up to 7 days. During the culture period studied,pancreatic beta cells were proliferating, with a global viabilityover 80% and tend to form pseudo-islets, thus suggesting thatthe proposed biomaterial could be a good candidate as versatilecarrier for diabetes treatment as they sustain the release of insulinand support pancreatic beta cells viability.We acknowledge ERDF for the financial support through POCTEP Project 0687_NOVOMAR_1_P, under the scope of INTERREG 2007-2013, and project 0302_CVMAR_I_1_P, under the scope of INTERREG Espana-Portugal 2014-2020, and Structured Projects NORTE-01-0145-FEDER-000021, NORTE-01-0145-FEDER-000023 and ATLANTIDA (ref. NORTE-01–0145-FEDER-000040), under the scope of Programa Operacional Regional do Norte (Norte 2020). Funding from the Portuguese Foundation for Science and Technology for doctoral grant (SFRH/BD/112139/2015) and post-doctoral grant (SFRH/BPD/85790/2012) is also acknowledge

    13th FINA world Championship: analysis of swimsuits used by elite male swimmers

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    The polyurethane swimsuits has become the notice around the pools in the past couple years. A better body position and the reducing of drag are believed to be some of the reasons that allow the swimmers wearing these swimsuits to go faster (Kainuma et al., 2009). The purpose of this study was to verify the distribution of different swimsuits used by male swimmers during the finals at the last world championships being held at Rome in 200
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