Browsing by Author "Costa-Pinto, Ana Rita"
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- Assessment of baby Bibs. GC-MS screening, migration into saliva and insight of toxicity with QSAR toolsPublication . Rajbux, Chandisree; Pereira, Joel; Selbourne, Maria do Céu; Costa-Pinto, Ana Rita; Poças, FátimaPlastic baby Bibs are, according to the European legislation, food contact materials. Therefore, compositional and migration limits applicable to plastics should be observed. This work aimed at identifying potential migrants in Bibs from European market and determining the migration into artificial saliva. Bibs were subjected to screening analyses (GC-MS). Thirty substances non-authorised in European or Swiss legislation were detected: phthalates, light stabilizers, flame retardants and photoinitiators. Irgacure 184, Cyclohexanone, Tinuvin 770, Isophorone and 9-Octadecenamide, (Z)- were detected in saliva after contact with selected Bibs. The migration values render two samples noncompliant although results should be interpreted with caution given the experimental conditions. In order to gain insight on the toxicity of migrants, QSAR tools were applied. Substances non-evaluated or not-listed were analysed with free software regarding their Cramer class (ToxTree and their predicted mutagenicity, carcinogenicity and developmental toxicity (VEGA). Results indicate that surveillance is required: monitoring Bibs'compliance, application of GMPs and traceability.
- Chitosan and hydroxyapatite based biomaterials to circumvent periprosthetic joint infectionsPublication . Costa-Pinto, Ana Rita; Lemos, Ana Luísa; Tavaria, Freni Kekhasharú; Pintado, ManuelaEvery year, worldwide, millions of people suffering from joint pain undergo joint replace-ment. For most patients, joint arthroplasty reduces pain and improve function, though a small fraction will experience implant failure. One of the main reasons includes prosthetic joint infection (PJI), involving the prosthesis and adjacent tissues. Few microorganisms (MO) are required to inocu-late the implant, resulting in the formation of a biofilm on its surface. Standard treatment includes not only removal of the infected prosthesis but also the elimination of necrotic bone fragments, local and/or systemic administration of antibiotics, and revision arthroplasty with a new prosthesis, immediately after the infection is cleared. Therefore, an alternative to the conventional therapeutics would be the incorporation of natural antimicrobial compounds into the prosthesis. Chitosan (Ch) is a potential valuable biomaterial presenting properties such as biocompatibility, biodegradability, low immunogenicity, wound healing ability, antimicrobial activity, and anti-inflammatory potential. Regarding its antimicrobial activity, Gram-negative and Gram-positive bacteria, as well as fungi are highly susceptible to chitosan. Calcium phosphate (CaP)-based materials are commonly utilized in orthopedic and dentistry for their excellent biocompatibility and bioactivity, particularly in the establishment of cohesive bone bonding that yields effective and rapid osteointegration. At present, the majority of CaP-based materials are synthetic, which conducts to the depletion of the natural resources of phosphorous in the future due to the extensive use of phosphate. CaP in the form of hydroxyapatite (HAp) may be extracted from natural sources as fish bones or scales, which are by-products of the fish food industry. Thus, this review aims to enlighten the fundamental characteristics of Ch and HAp biomaterials which makes them attractive to PJI prevention and bone regeneration, summarizing relevant studies with these biomaterials to the field.
- Continuous production of highly tuned silk/calcium-based composites: exploring new pathways for skin regenerationPublication . Veiga, Anabela; Magalhães, Rui; Duarte, Marta M.; Dias, Juliana R.; Alves, Nuno M.; Costa-Pinto, Ana Rita; Castro, Filipa; Rocha, Fernando; Oliveira, Ana L.Calcium plays an important role in barrier function repair and skin homeostasis. In particular, calcium phosphates (CaPs) are well established materials for biomedical engineering due to their biocompatibility. To generate biomaterials with a more complete set of biological properties, previously discarded silk sericin (SS) has been recovered and used as a template to grow CaPs. Crucial characteristics for skin applications, such as antibacterial activity, can be further enhanced by doping CaPs with cerium (Ce) ions. The effectiveness of cell attachment and growth on the materials highly depends on their morphology, particle size distribution, and chemical composition. These characteristics can be tailored through the application of oscillatory flow technology, which provides precise mixing control of the reaction medium. Thus, in the present work, CaP/SS and CaP/SS/Ce particles were fabricated for the first time using a modular oscillatory flow plate reactor (MOFPR) in a continuous mode. Furthermore, the biological behavior of both these composites and of previously produced pure CaPs was assessed using human dermal fibroblasts (HDFs). It was demonstrated that both CaP based with plate-shaped nanoparticles and CaP-SS-based composites significantly improved cell viability and proliferation over time. The results obtained represent a first step towards the reinvention of CaPs for skin engineering.
- Hydrolysates of mytilus galloprovincialis as a source of bioactive compoundsPublication . Cunha, Sara; Coscueta, Ezequiel; Nova, Paulo; Costa-Pinto, Ana Rita; Sarmento, Bruno; Pintado, Manuela
- In situ enabling approaches for tissue regeneration: current challenges and new developmentsPublication . Dias, Juliana R.; Ribeiro, Nilza; Baptista-Silva, Sara; Costa-Pinto, Ana Rita; Alves, Nuno; Oliveira, Ana. L.In situ tissue regeneration can be defined as the implantation of tissue-specific biomaterials (by itself or in combination with cells and/or biomolecules) at the tissue defect, taking advantage of the surrounding microenvironment as a natural bioreactor. Up to now, the structures used were based on particles or gels. However, with the technological progress, the materials’ manipulation and processing has become possible, mimicking the damaged tissue directly at the defect site. This paper presents a comprehensive review of current and advanced in situ strategies for tissue regeneration. Recent advances to put in practice the in situ regeneration concept have been mainly focused on bioinks and bioprinting techniques rather than the combination of different technologies to make the real in situ regeneration. The limitation of conventional approaches (e.g., stem cell recruitment) and their poor ability to mimic native tissue are discussed. Moreover, the way of advanced strategies such as 3D/4D bioprinting and hybrid approaches may contribute to overcome the limitations of conventional strategies are highlighted. Finally, the future trends and main research challenges of in situ enabling approaches are discussed considering in vitro and in vivo evidence.
- Microalgae as a source of natural ingredients for application in cosmetic industryPublication . Cunha, Sara A.; Costa-Pinto, Ana Rita; Silva, Joana L.; Sarmento, Bruno; Pintado, Manuela
- Mussel meat waste as a source of bioactive ingredients for industrial applicationPublication . Cunha, Sara A.; Nova, Paulo; Sarmento, Bruno; Costa-Pinto, Ana Rita; Pintado, Manuela E.Mussels are considered a delicacy appreciated in several countries, including Portugal. For commercialization, mussels need to fulfil the market criteria, such as size and condition. Thus, before being commercialized, mussels need to be pre-selected according to the target market requirements. Consequently, broken mussels or those with size out of the established criteria are discarded, corresponding to about 27% of the produced mussels. Mytilus galloprovincialis is rich in proteins and, consequently may be used to produce bioactive hydrolysates. Thus, in this study, we have used discarded mussel meat to obtain hydrolysates rich in proteins/peptides with bioactive properties. Mussel meat was minced until homogenised and then hydrolysed with a selected protease. The resulting hydrolysate showed 45% protein, antioxidant activity (ORAC assay) of 486 µmol TE/g of extract and anti-diabetic potential, since it was able to inhibit 90% of α-Glucosidase activity (30 mg/mL). The hydrolysate antioxidant potential is interesting for food and anti-aging cosmetics, since it may help control radical oxygen species generation. However, for food or supplements industries the antioxidant activity must be maintained after ingestion. So, the hydrolysate was submitted to an in vitro simulation of the gastrointestinal (GI) tract. We have verified that the antioxidant potential is maintained throughout all the GI ste ps, reinforcing the high potential of the hydrolysate for industrial applications. So, in this work, it was intended to give a regenerative approach to discarded mussels, by transforming their meat into hydrolysates rich in proteins/peptides and bioactive properties. The produced hydrolysate showed potential as antioxidant and anti-diabetic ingredients, able to resist to gastrointestinal digestion steps, revealing a high potential as an ingredient for the development of functional foods, supplements, or cosmetic formulations. This way, we can produce natural and sustainable value-added ingredients for commercial purposes, aligned with industrial and consumer trends while valorising mussel waste in a circular economy context.
- Sardine roe as a source of lipids to produce liposomesPublication . Guedes, Marta; Costa-Pinto, Ana Rita; Gonçalves, Virgínia; Moreira-Silva, Joana; Tiritan, Maria; Reis, Rui L.; Ferreira, Helena; Neves, Nuno M.Sea-derived materials have promising applications in the medical, pharmaceutical, and biotechnological fields. Fish roe, for example, is a highly nutritional product, presenting diverse beneficial effects on human health. Therefore, this work explored extracts of sardine (Sardina pilchardus) roe, due to the well-known health benefits of this fish, to produce novel and promising delivery systems. After morphological, histological, and histochemical characterizations of sardine roe, their lipids were extracted using two different approaches, namely, Bligh and Dyer (BD) and methyl-tert-butyl ether (MTBE) methods. Gas chromatography/mass spectrometry analyses demonstrated that lipid extracts contain several fatty acids, such as ω3 polyunsaturated fatty acids. The lipids, especially phospholipids, were used to produce multilamellar liposomes (MLVs). These delivery systems presented size heterogeneity, a negative surface charge, and the ability to control the release of the encapsulated anti-inflammatory drug, namely, celecoxib. Biological assays indicated that MLVs produced with MTBE lipidic extracts presented a better cytocompatibility than those obtained by the BD method. This can be further improved if the lipid extracts are processed by chemical extraction. Therefore, sardine roe-derived lipids can produce drug-delivery systems with the potential to be applied in the biomedical field.