Search Results - "Martins, Eva"

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Publication Catalog - "Martins, Eva"

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  1. 1

    3D biocomposites comprising marine collagen and silica-based materials inspired on the composition of marine sponge skeletons envisaging bone tissue regeneration

    Publication
    by Martins, Eva
    Other Authors: Diogo, Gabriela S.; Pires, R. A.; Reis, R. L.; Silva, Tiago H.
    Ocean resources are a priceless repository of unique species and bioactive compounds with denouement properties that can be used in the fabrication of advanced biomaterials as new templates for supporting the cell culture envisaging tissue engineering approaches. The collagen of marine origin can be sustainably isolated from the underrated fish processing industry by-products, while silica and related materials can be found in the spicules of marine sponges and diatoms frustules. Aiming to address the potential of biomaterials composed from marine collagen and silica-based materials in the context of bone regeneration, four different 3D porous structure formulations (COL, COL:BG, COL:D.E, and COL:BS) were fabricated by freeze-drying. The skins of Atlantic cod (Gadus morhua) were used as raw materials for the collagen (COL) isolation, which was successfully characterized by SDS-PAGE, FTIR, CD, and amino acid analyses, and identified as a type I collagen, produced with a 1.5% yield and a preserved characteristic triple helix conformation. Bioactive glass 45S5 bioglass® (BG), diatomaceous earth (D.E.) powder, and biosilica (BS) isolated from the Axinella infundibuliformis sponge were chosen as silica-based materials, which were obtained as microparticles and characterized by distinct morphological features. The biomaterials revealed microporous structures, showing a porosity higher than 85%, a mean pore size range of 138–315 μm depending on their composition, with 70% interconnectivity which can be favorable for cell migration and ensure the needed nutrient supply. In vitro, biological assays were conducted by culturing L929 fibroblast-like cells, which confirmed not only the non-toxic nature of the developed biomaterials but also their capability to support cell adhesion and proliferation, particularly the COL:BS biomaterials, as observed by calcein-AM staining upon seven days of culture. Moreover, phalloidin and DAPI staining revealed well-spread cells, populating the entire construct. This study established marine collagen/silica biocomposites as potential scaffolds for tissue engineering, setting the basis for future studies, particularly envisaging the regeneration of non-load-bearing bone tissues.
    2022 article Portugal open access
  2. 2

    Bleached hair as standard template to insight the performance of commercial hair repair products

    Publication
    by Martins, Eva
    Other Authors: Castro, Pedro; Ribeiro, Alessandra B.; Pereira, Carla F.; Casanova, Francisca; Vilarinho, Rui et al.
    The increasing demand for effective hair care products has highlighted the necessity for rigorous claims substantiation methods, particularly for products that target specific hair types. This is essential because the effectiveness of a product can vary significantly based on the hair’s condition and characteristics. A well-defined bleaching protocol is crucial for creating a standardized method to assess product efficacy, especially for products designed to repair damaged hair. The objective of this study was to create a practical bleaching protocol that mimics real-world consumer experiences, ensuring that hair samples exhibit sufficient damage for testing. This approach allows for a reliable assessment of how well various products can repair hair. The protocol serves as a framework for evaluating hair properties and the specific effects of each product on hair structure. Color, brightness, lightness, morphology, and topography were primarily used to understand the big differences in the hair fiber when treated with two repair benchmark products, K18® and Olaplex®, in relation to the Bleached hair. The devised bleaching protocol proved to be a fitting framework for assessing the properties of hair and the unique characteristics of each tested product within the hair fiber. This protocol offers valuable insights and tools for substantiating consumer claims, with morphological and mechanical methods serving as indispensable tools for recognizing and validating claims related to hair. The addition of K18® and Olaplex® demonstrated an increase in hair brightness (Y) and lightness (L* and a*) in relation to the Bleached samples, which were considered relevant characteristics for consumers. Olaplex®’s water-based nature creates a visible inner sheet, effectively filling empty spaces and improving the disulfide linkage network. This enhancement was corroborated by the increased number of disulfide bonds and evident changes in the FTIR profile. In contrast, K18®, owing to the lipophilic nature of its constituents, resulted in the formation of an external layer above the fiber. The composition of each of the products had a discrete impact on the fiber distribution, which was an outcome relevant to the determination of spreadability by consumers.
    2024 article Portugal open access
  3. 3

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

    Publication
    by Martins, Eva
    Other Authors: Reis, Rui L.; Silva, Tiago H.
    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.
    2023 article Portugal open access
  4. 4

    Skin byproducts of reinhardtius hippoglossoides (Greenland Halibut) as ecosustainable source of marine collagen

    Publication
    by Martins, Eva
    Other Authors: Fernandes, Rita; Alves, Ana L.; Sousa, Rita O.; Reis, R. L.; Silva, Tiago H.
    Collagen is a ubiquitous protein present in the extracellular matrix of all major metazoan animals, with approximately 28 different human collagen types described in the literature, each with unique physicochemical properties. Collagens found broad application in the cosmeceutical, pharmaceutical, and biomedical fields and can be isolated from environmentally sustainable sources such as marine byproducts, which are abundant in the fish processing industry and are highly appealing low-cost sources. In this study, marine collagen was isolated from the skins of Greenland halibut (Reinhardtius hippoglossoides), an unexplored byproduct from fish processing plants, using three different collagen extraction methods, due to the use of distinct salting-out methods using a solution of 2.6 M NaCl + 0.05 M Tris-HCl pH = 7.5, (method I); a combination of 0.7 M NaCl followed by a solution of 2.3 M NaCl + 0.05 M Tris-HCl pH = 7.5 (method II); and one method using only 0.9 M NaCl (method III), yielding COLRp_I, COLRp_II, and COLRp_III collagens. These extracted type I collagens were produced with a yield of around 2 and 4% and characterized regarding the physicochemical properties, considering possible biotechnological applications. This work evidenced that the typical triple helix structure conformation was preserved in all extraction methods, but influenced the thermal behavior, intrinsic morphology, and moisture capacity of the collagens, with interest for biotechnological application, as the incorporation as an ingredient in cosmetic formulation. Furthermore, the use of collagen isolated from skin byproducts represents a high economic value with decreasing collagen cost for industrial purposes and is also an environmentally sustainable source for industrial uses.
    2022 article Portugal open access
  5. 5

    Macro and microstructural characteristics of north Atlantic deep-sea sponges as bioinspired models for tissue engineering scaffolding

    Publication
    by Martins, Eva
    Other Authors: Rapp, Hans Tore; Xavier, Joana R.; Diogo, Gabriela S.; Reis, R. L.; Silva, Tiago H.
    Sponges occur ubiquitously in the marine realm and in some deep-sea areas they dominate the benthic communities forming complex biogenic habitats – sponge grounds, aggregations, gardens and reefs. However, deep-sea sponges and sponge-grounds are still poorly investigated with regards to biotechnological potential in support of a Blue growth strategy. Under the scope of this study, five dominant North Atlantic deep-sea sponges, were characterized to elucidate promising applications in human health, namely for bone tissue engineering approaches. Geodia barretti (Gb), Geodia atlantica (Ga), Stelletta normani (Sn), Phakellia ventilabrum (Pv), and Axinella infundibuliformis (Ai), were morphologically characterized to assess macro and microstructural features, as well as chemical composition of the skeletons, using optical and scanning electron microscopy, energy dispersive x-ray spectroscopy and microcomputed tomography analyses. Moreover, compress tests were conducted to determine the mechanical properties of the skeletons. Results showed that all studied sponges have porous skeletons with porosity higher than 68%, pore size superior than 149 μm and higher interconnectivity (>96%), thus providing interesting models for the development of scaffolds for tissue engineering. Besides that, EDS analyses revealed that the chemical composition of sponges, pointed that demosponge skeletons are mainly constituted by carbon, silicon, sulfur, and oxygen combined mutually with organic and inorganic elements embedded its internal architecture that can be important features for promoting bone matrix quality and bone mineralization. Finally, the morphological, mechanical, and chemical characteristics here investigated unraveled the potential of deep-sea sponges as a source of biomaterials and biomimetic models envisaging tissue engineering applications for bone regeneration.
    2021 article Portugal open access
  6. 6

    Remarkable body architecture of marine sponges as biomimetic structure for application in tissue engineering

    Publication
    by Martins, Eva
    Other Authors: Rocha, M. S.; Silva, Tiago José Quinteiros Lopes Henriques; Reis, R. L.
    Recent advances in the study of marine environment, particularly of marine organismsâ architecture and composition, have isolated interesting compounds as proteins, GAG-like polysaccharides and bioactive compounds. These compounds have allowed the development of panoply of biomaterials inspired by morphological characteristics and anatomical structures of the marine species. Besides, the scientific community acknowledges the enormous biotechnological potential in the marine resources that can be a promising effective and efficient alternative to be used in Human health, namely tissue engineering and regenerative medicine, as well as to support the progress in pharmacological, cosmetic, nutraceutical and biomedical fields. Additionally, sustainable ways are being applied to explore these marine resources and address biomimetic approaches, aiming to take the most out of the astonishing marine environment in ecologically compatible ways. Marine sponges are a particular group of organisms feeding these biotechnological developments for human health, both as source of new drugs or inspiration for the development of marine biomaterials. This chapter aims to demonstrate, in a concise and clear way, the biotechnological potential of marine sponges used as susceptive bioscaffolds for regenerative medicine and biomedical applications in general.
    2019 book part Portugal restricted access
  7. 7
  8. 8

    Emotion understanding in preschool children : The role of executive functions

    Publication
    by Martins, Eva Costa
    Other Authors: Osório, Ana; Veríssimo, Manuela; Martins, Carla
    Abstract This investigation was aimed at studying the relations between executive functions (EFs) and categorical emotion understanding while controlling for preschoolers’ IQ, language ability and theory of mind (ToM). Specifically, we wanted to analyse the association between emotion understanding and set shifting, due to the lack of studies with this EF. Data of 75 children aged 4½ years (52% boys) was collected in two laboratory visits. Emotion understanding was assessed using the Emotion Recognition Questionnaire, inhibitory control using the Head-Toes-Knees-Shoulders task and set shifting using a version of the Dimensional Change Card Sort task. IQ was evaluated using the WPPSI-R, language using the Peabody Picture Vocabulary Test – Revised; and ToM using six standardized tasks. Set shifting, but not inhibitory control, predicted emotion understanding, over and above mothers’ age, and children’s IQ, language ability, and ToM. Mothers’ age and children’s language ability were also significant predictors in the final regression model. Results suggest that the capacity to shift mental sets is linked with inter-individual differences in children’s understanding of situational causes of emotion. Therefore studying EFs as correlates of emotion understanding is an important focus of future research.
    2016 article Portugal restricted access
  9. 9
  10. 10

    On the importance of being flexible: early interrelations between affective flexibility, executive functions and anxiety symptoms in preschoolers

    Publication
    by Martins, Eva C.
    Other Authors: Mărcuș, Oana; Sassu, Raluca
    When children are confronted with an emotional problem, affective flexibility mobilizes their cognitive and emotional resources to optimally address it. We investigated the contribution of executive functions to cognitive and affective flexibility in preschoolers. We assessed affective flexibility in 67 preschoolers (30 girls; Mmonths = 61.77, SD = 11.08 months) using an innovative measure – the Emotional Flexible Item Selection Task (EM-FIST), plus cool measures of executive functions (working memory, inhibition and cognitive flexibility), anxiety symptoms and intelligence. Findings revealed that affective flexibility improves during the preschool years. While individual differences in age and proactive inhibition predicted cognitive flexibility, a different constellation of predictors (maternal education, proactive inhibition, working memory and age) were significant for affective flexibility. Cognitive flexibility didn’t contribute to affective flexibility beyond the predictors mentioned above. Anxiety exerted a negative effect on affective flexibility in a high anxious subgroup of preschoolers, but only when processing negative, relative to happy faces, supporting the Attentional Control Theory which predicts valence-related executive impairments
    2020 article Portugal open access