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In this paper, we cover 4 years of live fish transports that ranged from 14 to 200 h (8 days), and bioloads from 3.8 to 76.9 kg/m3 . The key ingredients for success in all trips, where virtually no mortality occurred, was atributed to (1) pre-buffering the water with sodium bicarbonate and sodium carbonate at 50 g/m3 (each)-and/or ATM Alka-HaulTM at 25 g/m3 -and applying additional (partial or full) doses throughout each transport, whenever the tanks were accessible; (2) pre-quenching ammonia with ATM TriageTM at 32 g/m3 , and applying additional (partial or full) doses throughout each transport, whenever the tanks were accessible; (3) keeping the dissolved oxygen saturation rate above 100%, ideally above 150%; (4) Keeping temperature on the lower limit of each species' tolerance range; (5) Using foam fractionators to effectively eliminate organic matter from the water and (6) Using pure sine wave inverters, which allows for a steady supply of electrical current throughout the transport. The use of a 'preventive' versus 'corrective' pH buffering philosophy is also discussed.
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Salmo salar , Animales , Agua , Animales de ZoológicoRESUMEN
After hatching, sea turtles leave the nest and disperse into the ocean. Many years later, they return to their natal coastlines. The period between their leaving and their returning to natal areas, known as the "Lost Years", is poorly understood. Satellite tracking studies aimed at studying the "Lost Years" are challenging due to the small size and prolonged dispersal phases of young individuals. Here, we summarize preliminary findings about the performance of prototype microsatellite tags deployed over a three-year period on 160 neonate to small juvenile sea turtles from four species released in the North Atlantic Ocean. We provide an overview of results analyzing tag performance with metrics to investigate transmission characteristics and causes of tag failure. Our results reveal that, despite certain unfavorable transmission features, overall tag performance was satisfactory. However, most track durations were shorter than those observed on individuals of similar size in other studies and did not allow for detailed analyses of trajectories and turtle behavior. Our study further suggests that tracking durations are correlated with the targeted species, highlighting a lack of robustness against some neritic behaviors. Unprecedented diving data obtained for neonate sea turtles in this study suggest that the vertical behaviors of early juveniles are already too strenuous for these miniaturized tags. Our findings will help to inform the biologging research community, showcasing recent technological advances for the species and life stages within our study.
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Polymer-matrix composites are widely used in engineering applications. Yet, environmental factors impact their macroscale fatigue and creep performances significantly, owing to several mechanisms acting at the microstructure level. Herein, we analyse the effects of water uptake that are responsible for swelling and, over time and in enough quantity, for hydrolysis. Seawater, due to a combination of high salinity and pressures, low temperature and biotic media present, also contributes to the acceleration of fatigue and creep damage. Similarly, other liquid corrosive agents penetrate into cracks induced by cyclic loading and cause dissolution of the resin and breakage of interfacial bonds. UV radiation either increases the crosslinking density or scissions chains, embrittling the surface layer of a given matrix. Temperature cycles close to the glass transition damage the fibre-matrix interface, promoting microcracking and hindering fatigue and creep performance. The microbial and enzymatic degradation of biopolymers is also studied, with the former responsible for metabolising specific matrices and changing their microstructure and/or chemical composition. The impact of these environmental factors is detailed for epoxy, vinyl ester and polyester (thermoset); polypropylene, polyamide and poly etheretherketone (thermoplastic); and for poly lactic acid, thermoplastic starch and polyhydroxyalkanoates (biopolymers). Overall, the environmental factors mentioned hamper the fatigue and creep performances, altering the mechanical properties of the composite or causing stress concentrations through microcracks, promoting earlier failure. Future studies should focus on other matrices beyond epoxy as well as on the development of standardised testing methods.
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Infantile haemangiomas (IHs) are the most common benign soft tissue tumours in children. Usually, they evolve without clinical incurrences and regression of the lesion can occur spontaneously in the first years of life. The decision for treatment is dependent upon the intrinsic characteristics of the lesion such as location, extension, functional compromise and complications. We present the case of a newborn who was clinically accessed during ambulatory routine consultation when a lesion with 5x5 centimetres compatible with an IH was first observed. Inflammatory signs with no active bleeding were present and the newborn displayed signs of discomfort during a diaper change and manipulation of the anogenital area. For this reason, a referral was made for observation in a central hospital with specialised paediatrics, paediatric surgery and dermatology support. A 10-day antibiotic course with flucloxacillin and local topical care with silver sulfadiazine cream and barrier cream with zinc oxide were adopted, achieving a good clinical outcome. Laboratory workup, cardiovascular assessment, imagiological investigation with abdominopelvic and spinal cord ultrasonography as well as lumbosacral magnetic resonance imaging were all normal. Ulceration is the most prevalent complication of IHs and it is associated with pain, recurrent bleeding, infection and difficult scarring, thus early recognition and directed treatment are essential to achieve a good clinical outcome.
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Osteoarthritis (OA) is the most prevalent type of degenerative joint disease, and its pathological progression is highly associated with oxidative stress. Natural antioxidants can attenuate oxidative stress and chondrocyte injury, suggesting that antioxidants have potential applications in the management of OA. Ellagic acid (EA), a natural polyphenol derived from fruits or nuts, exerts antioxidant and anti-inflammatory effects in diseases related to oxidative stress. Herein, we investigated the effects of EA on interleukin-1ß (IL-1ß)-induced oxidative stress and degeneration in C28/I2 human chondrocytes. EA efficiently suppressed IL-1ß-induced oxidative stress and ameliorated oxidative stress-induced dysfunction of chondrocytes, as indicated by the promotion of cartilage matrix secretion. Moreover, EA remarkably suppressed cell apoptosis and senescence, and reduced the expression of proinflammatory factors and metalloproteinases, suggesting that EA could alleviate chondrocyte injury under oxidative stress. Mechanistically, EA upregulated the expression of nuclear factor erythroid 2-related factor 2 (Nrf2) as well as its downstream targets NADPH quinone oxidoreductase 1 and heme oxygenase-1. ML385, a specific Keap1/Nrf2 pathway inhibitor, blocked the antioxidant and chondroprotective effects of EA. Our findings demonstrated that EA could attenuate oxidative stress and exert protective effects on chondrocytes by upregulating the Keap1/Nrf2 signaling pathway.
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Condrocitos , Factor 2 Relacionado con NF-E2 , Antioxidantes/farmacología , Condrocitos/metabolismo , Ácido Elágico/metabolismo , Ácido Elágico/farmacología , Humanos , Interleucina-1beta/metabolismo , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Estrés OxidativoRESUMEN
To modulate the physicochemical features of poly(ethylene terephthalate) (PET) multifilaments surface composing a complex textile structure (core and shell system), intended to improve upon current implants for high extension injuries of the Achilles tendon or even for its total replacement, two surface treatments with different purposes (bioactive and biopassive) were studied. The first treatment is based on amino groups grafting using ethylenediamine molecules to be applied in the structure core to improve cell adhesion and proliferation. The other treatment relates to a polytetrafluoroethylene (PTFE) coating to be applied in the structure shell to decrease its coefficient of friction and avoid adhesions. Both treatments were optimized to reach their purposed goals without harming the tensile properties of PET yarns, which were evaluated by static tensile tests. The resazurin assay and scanning electron microscopy analysis showed that the purposed goals related to fibroblast adhesion were achieved for both treatments and in the case of PTFE coating, the abrasion resistance was also improved according to the yarn-on-yarn abrasion tests.
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Tereftalatos Polietilenos , Textiles , Etilenos , Fibroblastos , Ácidos FtálicosRESUMEN
BACKGROUND: The adherence to inhaled controller medications is of critical importance for achieving good clinical results in patients with chronic respiratory diseases. Self-management strategies can result in improved health outcomes and reduce unscheduled care and improve disease control. However, adherence assessment suffers from difficulties on attaining a high grade of trustworthiness given that patient self-reports of high-adherence rates are known to be unreliable. OBJECTIVE: Aiming to increase patient adherence to medication and allow for remote monitoring by health professionals, a mobile gamified application was developed where a therapeutic plan provides insight for creating a patient-oriented self-management system. To allow a reliable adherence measurement, the application includes a novel approach for objective verification of inhaler usage based on real-time video capture of the inhaler's dosage counters. METHODS: This approach uses template matching image processing techniques, an off-the-shelf machine learning framework, and was developed to be reusable within other applications. The proposed approach was validated by 24 participants with a set of 12 inhalers models. RESULTS: Performed tests resulted in the correct value identification for the dosage counter in 79% of the registration events with all inhalers and over 90% for the three most widely used inhalers in Portugal. These results show the potential of exploring mobile-embedded capabilities for acquiring additional evidence regarding inhaler adherence. CONCLUSION: This system helps to bridge the gap between the patient and the health professional. By empowering the first with a tool for disease self-management and medication adherence and providing the later with additional relevant data, it paves the way to a better-informed disease management decision.
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Cumplimiento de la Medicación , Aplicaciones Móviles , Humanos , Nebulizadores y Vaporizadores , PortugalRESUMEN
Anterior cruciate ligament (ACL) reconstructive surgeries are the most frequent orthopedic procedures in the knee. Currently, existing strategies fail in completely restoring tissue functionality and have a high failure rate associated, presenting a compelling argument towards the development of novel materials envisioning ACL reinforcement. Tendons and ligaments, in general, have a strong demand in terms of biomechanical features of developed constructs. We have previously developed polylactic acid (PLA)-based biodegradable films reinforced either with graphene nanoplatelets (PLA/GNP) or with carboxyl-functionalized carbon nanotubes (PLA/CNT-COOH). In the present study, we comparatively assessed the biological performance of PLA, PLA/GNP, and PLA/CNT-COOH by seeding human dermal fibroblasts (HFF-1) and studying cell viability and proliferation. In vivo tests were also performed by subcutaneous implantation in 6-week-old C57Bl/6 mice. Results showed that all formulations studied herein did not elicit cytotoxic responses in seeded HFF-1, supporting cell proliferation up to 3 days in culture. Moreover, animal studies indicated no physiological signs of severe inflammatory response after 1 and 2 weeks after implantation. Taken together, our results present a preliminary assessment on the compatibility of PLA reinforced with GNP and CNT-COOH nanofillers, highlighting the potential use of these carbon-based nanofillers for the fabrication of reinforced synthetic polymer-based structures for ACL reinforcement. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 2182-2190, 2017.
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Materiales Biocompatibles/química , Fibroblastos/citología , Grafito/química , Nanotubos de Carbono/química , Poliésteres/química , Implantes Absorbibles , Animales , Ligamento Cruzado Anterior/cirugía , Línea Celular , Proliferación Celular , Supervivencia Celular , Humanos , Ligamentos/cirugía , Ratones , Ratones Endogámicos C57BL , Nanocompuestos/química , Procedimientos de Cirugía Plástica , Tendones/cirugíaRESUMEN
The large surface area and ability to retain moisture of textile structures enable microorganisms' growth, which causes a range of undesirable effects, not only on the textile itself, but also on the user. Due to the public health awareness of the pathogenic effects on personal hygiene and associated health risks, over the last few years, intensive research has been promoted in order to minimize microbes' growth on textiles. Therefore, to impart an antimicrobial ability to textiles, different approaches have been studied, being mainly divided into the inclusion of antimicrobial agents in the textile polymeric fibers or their grafting onto the polymer surface. Regarding the antimicrobial agents, different types have been used, such as quaternary ammonium compounds, triclosan, metal salts, polybiguanides or even natural polymers. Any antimicrobial treatment performed on a textile, besides being efficient against microorganisms, must be non-toxic to the consumer and to the environment. This review mainly intends to provide an overview of antimicrobial agents and treatments that can be performed to produce antimicrobial textiles, using chemical or physical approaches, which are under development or already commercially available in the form of isolated agents or textile fibers or fabrics.
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The use of biodegradable synthetic grafts to repair injured ligaments may overcome the disadvantages of other solutions. Apart from biological compatibility, these devices shall also be functionally compatible and temporarily displayed, during the healing process, adequate mechanical support. Laxity of these devices is an important concern. This can cause failure since it may result in joint instability. Laxity results from a progressive accumulation of plastic strain during the cyclic loading. The functional compatibility of a biodegradable synthetic graft and, therefore, the global mechanical properties of the scaffold during degradation, can be optimised using computer-aiding and numerical tools. Therefore, in this work, the ability of numerical tools to predict the mechanical behaviour of the device during its degradation is discussed. Computational approaches based on elastoplastic and viscoplastic constitutive models are also presented. These models enable to simulate the plastic strain accumulation. These computational approaches, where the material model parameters depend on the hydrolytic degradation damage, are calibrated using experimental data measured from biodegradable suture fibres at different degradation steps. Due to durability requirements the selected materials are polydioxone (PDO) and polylactic acid and poly-caprolactone blend (PLA-PCL). Computational approaches investigated are able to predict well the experimental results for both materials, in full strain range until rupture and for different degradation steps. These approaches can be further used in more complex fibrous structures, to predict its global mechanical behaviour during degradation process.