Plastics are essential in society as a widely available and inexpensive material. Mismanagement of personal protective equipment (PPE) during the COVID-19 pandemic, with a monthly estimated use of ...129 billion face masks and 65 billion gloves globally, is resulting in widespread environmental contamination. This poses a risk to public health as waste is a vector for SARS-CoV-2 virus, which survives up to 3 days on plastics, and there are also broad impacts to ecosystems and organisms. Concerns over the role of reusable plastics as vectors for SARS-CoV-2 virus contributed to the reversal of bans on single-use plastics, highly supported by the plastic industry. While not underestimating the importance of plastics in the prevention of COVID-19 transmission, it is imperative not to undermine recent progress made in the sustainable use of plastics. There is a need to assess alternatives that allow reductions of PPE and reinforce awareness on the proper public use and disposal. Finally, assessment of contamination and impacts of plastics driven by the pandemic will be required once the outbreak ends.
Collagens are the most abundant high molecular weight proteins in both invertebrate and vertebrate organisms, including mammals, and possess mainly a structural role, existing different types ...according with their specific organization in distinct tissues. From this, they have been elected as one of the key biological materials in tissue regeneration approaches. Also, industry is constantly searching for new natural sources of collagen and upgraded methodologies for their production. The most common sources are from bovine and porcine origin, but other ways are making their route, such as recombinant production, but also extraction from marine organisms like fish. Different organisms have been proposed and explored for collagen extraction, allowing the sustainable production of different types of collagens, with properties depending on the kind of organism (and their natural environment) and extraction methodology. Such variety of collagen properties has been further investigated in different ways to render a wide range of applications. The present review aims to shed some light on the contribution of marine collagens for the scientific and technological development of this sector, stressing the opportunities and challenges that they are and most probably will be facing to assume a role as an alternative source for industrial exploitation.
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Natural biomaterials such as collagen show promise in tissue engineering applications due to their inherent bioactivity. The main limitation of collagen is its low mechanical strength ...and somewhat unpredictable and rapid degradation rate; however, combining collagen with another material, such as chitosan, can reinforce the scaffold mechanically and may improve the rate of degradation. Additionally, the high cost and the risk of prion transmission associated with mammal-derived collagen has prompted research into alternative sources such as marine-origin collagen. In this context, the overall goal of this study was to determine if the incorporation of chitosan into collagen scaffolds could improve the mechanical and biological properties of the scaffold. In addition the study assessed if collagen, derived from salmon skin (marine), can provide an alternative to collagen derived from bovine tendon (mammal) for tissue engineering applications. Scaffold architecture and mechanical properties were assessed as well as their ability to support mesenchymal stem cell growth and differentiation. Overall, the addition of chitosan to bovine and salmon skin-derived collagen scaffolds improved the mechanical properties, increasing the compressive strength, swelling ratio and prolonged the degradation rate. Mesenchymal stem cell (MSC) attachment and proliferation was most improved on the bovine-derived collagen scaffold containing a 75:25 ratio of collagen:chitosan, and when MSC osteogenic and chondrogenic potential on the scaffold was assessed, a significant increase in calcium production (p<0.001) and sulfated glycosaminoglycan (sGAG) production (p<0.001) was observed respectively. Regardless of chitosan content, the bovine-derived collagen scaffolds out-performed the salmon skin-derived collagen scaffolds, displaying a larger pore size and higher percentage porosity, more regular architecture, higher compressive modulus, a greater capacity for water uptake and allowed for more MSC proliferation and differentiation. This versatile scaffold incorporating the marine biomaterial chitosan show great potential as appropriate platforms for promoting orthopaedic tissue repair while the use of salmon skin-derived collagen may be more suitable in the repair of soft tissues such as skin.
Collagen is commonly used in tissue engineering due to its biocompatibility; however, it has low mechanical strength and an unpredictable degradation rate. In addition, high cost and risk of prion transmission associated with mammalian-derived collagen has prompted research into alternative collagen sources, namely, marine-derived collagen. In this study, scaffolds made from salmon-skin collagen were compared to the more commonly used bovine-derived collagen with a focus on orthopaedic applications. To improve the mechanical properties of these scaffolds, another marine biomaterial, chitosan, was added to produce scaffolds with increased mechanical stability. The collagen-chitosan composites were also shown to support mesenchymal stem cell differentiation towards both bone and cartilage tissue. This multi-functional scaffold therefore has potential in both bone and cartilage regeneration applications.
It is well established that magnesium has a considerable potential for use as a biodegradable material. This report describes the effect of processing by severe plastic deformation (SPD) on the grain ...refinement, mechanical behavior, biocompatibility and corrosion behavior of commercial purity magnesium. The material was received as cast slabs and processed by rolling, equal-channel angular pressing and high-pressure torsion to produce samples with average grain sizes in the range of ~0.5–300 μm. The results show that severe plastic deformation does not affect the biocompatibility. However, the corrosion behavior is affected by the processing route. Specifically, SPD processing leads to general corrosion as opposed to localized corrosion in the as-cast and hot-rolled condition.
The lectins are carbohydrate-binding proteins that are highly specific to sugar groups associated to other molecules. In addition to interacting with carbohydrates, a number of studies have reported ...the ability of these proteins to modulate the activity of several antibiotics against multidrug-resistant (MDR) strains. In this study, we report the enhanced antibacterial activity of the gentamicin against MDR strains when complexed with a lectin from Canavalia ensiformis seeds (ConA). Hemagglutination activity test and intrinsic fluorescence spectroscopy revealed that the gentamicin can interact with ConA most likely via the carbohydrate recognition domain (CRD) with binding constant (Kb) value estimated of (0.44 ± 0.04) x 104 M−1. Furthermore, the minimum inhibitory concentrations (MIC) obtained for ConA against all strains studied were not clinically relevant (MIC ≥ 1024 μg/mL). However, when ConA was combined with gentamicin, a significant increase in antibiotic activity was observed against Staphylococcus aureus and Escherichia coli. The present study showed that ConA has an affinity for gentamicin and modulates its activity against MDR strains. These results indicate that ConA improves gentamicin performance and is a promising candidate for structure/function analyses.
•ConA showed interaction with gentamicin.•ConA enhances the gentamicin activity against multi-resistant bacterial strains.•ConA may be an alternative in the control of multi-resistant strains.
Laser‐assisted indocyanine green angiography allows surgeons to determine intraoperative flap perfusion and achieve the best outcomes in breast reconstruction. This study stratified outcomes based on ...a meta‐analysis of complications including longitudinal trials comparing the clinical assessment of skin flaps during breast reconstruction. Nine studies met inclusion criteria and reported outcomes of interest (n = 2256). The risk of flap necrosis and the necessity of reoperation was statistically significantly higher in the control group.
In this paper, we provide a retrospective cohort study with patients that have been hospitalized for general or intensive care unit admission due to COVID-19, between March 3 and July 29, 2020, in ...the state of Bahia, Brazil. We aim to correlate those patients' demographics, symptoms and comorbidities, with the risk of mortality from COVID-19, length of hospital stay, and time from diagnosis to definitive outcome. On the basis of a dataset provided by the Health Secretary of the State of Bahia, we selected 3,896 hospitalized patients from a total of 154,868 COVID-19 patients that included non-hospitalized patients and patients with invalid registration in the dataset. Then, we statistically analyzed whether there was a significant correlation between the patient record data and the COVID-19 pandemic, and our main findings reinforced by the use of a multivariable logistic regression were that older age (Odds Ratio OR = 1.03, 95% Confidence Interval CI = 1.03-1.04, p-value (p) <0.001), an initial symptom of shortness of breath (OR = 1.88, 95% CI = 1.60-2.20, p < 0.001), and the presence of comorbidities, mainly chronic kidney disease (OR = 2.41, 95% CI = 1.67-3.48, p < 0.001) are related to an increased risk of mortality from COVID-19. On the other hand, sore throat (OR = 0.74, 95% CI = 0.58-0.95, p = 0.02) and length of hospital stay (OR = 0.96, 95% CI = 0.58-0.95, p < 0.001) are more related to a reduced risk of mortality from COVID-19. Moreover, a multivariable linear regression conducted with statistically significant variables (p < 0.05) showed that age (OR = 0.97, 95% CI = 0.95-0.98, p < 0.001) and time from diagnosis to definitive outcome (OR = 1.67, 95% CI = 1.64-1.71, p < 0.001) are associated with the length of hospital stay.
Many cosmetic formulations have collagen as a major component because of its significant benefits as a natural humectant and moisturizer. This industry is constantly looking for innovative, ...sustainable, and truly efficacious products, so marine collagen based formulations are arising as promising alternatives. A solid description and characterization of this protein is fundamental to guarantee the highest quality of each batch. In the present study, we present an extensive characterization of marine-derived collagen extracted from salmon and codfish skins, targeting its inclusion as component in cosmetic formulations. Chemical and physical characterizations were performed using several techniques such as sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE), Fourier Transformation Infrared (FTIR) spectroscopy rheology, circular dichroism, X-ray diffraction, humidity uptake, and a biological assessment of the extracts regarding their irritant potential. The results showed an isolation of type I collagen with high purity but with some structural and chemical differences between sources. Collagen demonstrated a good capacity to retain water, thus being suitable for dermal applications as a moisturizer. A topical exposure of collagen in a human reconstructed dermis, as well as the analysis of molecular markers for irritation and inflammation, exhibited no irritant potential. Thus, the isolation of collagen from fish skins for inclusion in dermocosmetic applications may constitute a sustainable and low-cost platform for the biotechnological valorization of fish by-products.
Nanotechnology has played a prominent role in biomedical engineering, offering innovative approaches to numerous treatments. Notable advances have been observed in the development of medical devices, ...contributing to the advancement of modern medicine. This article briefly discusses key applications of nanotechnology in tissue engineering, controlled drug release systems, biosensors and monitoring, and imaging and diagnosis. The particular emphasis on this theme will result in a better understanding, selection, and technical approach to nanomaterials for biomedical purposes, including biological risks, security, and biocompatibility criteria.
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