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•Plastic policy was adapted due to COVID-19 pandemic.•COVID-19 pandemic is contributing to worldwide plastic pollution.•COVID-19 precautionary measures challenged environmental ...sustainability.•Sustainability calls for straightened links between policy-industry-research.
Plastics have become a severe transboundary threat to natural ecosystems and human health, with studies predicting a twofold increase in the number of plastic debris (including micro and nano-sized plastics) by 2030. However, such predictions will likely be aggravated by the excessive use and consumption of single-use plastics (including personal protective equipment such as masks and gloves) due to COVID-19 pandemic. This review aimed to provide a comprehensive overview on the effects of COVID-19 on macroplastic pollution and its potential implications on the environment and human health considering short- and long-term scenarios; addressing the main challenges and discussing potential strategies to overcome them. It emphasises that future measures, involved in an emergent health crisis or not, should reflect a balance between public health and environmental safety as they are both undoubtedly connected. Although the use and consumption of plastics significantly improved our quality of life, it is crucial to shift towards sustainable alternatives, such as bio-based plastics. Plastics should remain in the top of the political agenda in Europe and across the world, not only to minimise plastic leakage and pollution, but to promote sustainable growth and to stimulate both green and blue- economies. Discussions on this topic, particularly considering the excessive use of plastic, should start soon with the involvement of the scientific community, plastic producers and politicians in order to be prepared for the near future.
Plastic yearly production has surpassed the 300milliontons mark and recycling has all but failed in constituting a viable solution for the disposal of plastic waste. As these materials continue to ...accumulate in the environment, namely, in rivers and oceans, in the form of macro-, meso-, micro- and nanoplastics, it becomes of the utmost urgency to find new ways to curtail this environmental threat. Multiple efforts have been made to identify and isolate microorganisms capable of utilizing synthetic polymers and recent results point towards the viability of a solution for this problem based on the biodegradation of plastics resorting to selected microbial strains.
Herein, the response of the fungus Zalerion maritimum to different times of exposition to polyethylene (PE) pellets, in a minimum growth medium, was evaluated, based on the quantified mass differences in both the fungus and the microplastic pellets used. Additionally, molecular changes were assessed through attenuated total reflectance Fourier transform Infrared Spectroscopy (FTIR-ATR) and Nuclear Magnetic Resonance (NMR).
Results showed that, under the tested conditions, Z. maritimum is capable of utilizing PE, resulting in the decrease, in both mass and size, of the pellets. These results indicate that this naturally occurring fungus may actively contribute to the biodegradation of microplastics, requiring minimum nutrients.
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•Plastic pollution is of growing concern as it accumulates in the environment.•Multiple microorganisms have been described as potential bioremediation solutions.•The potential of Zalerion maritimum in the biodegradation of polyethylene was tested.•Z. maritimum used polyethylene as evidenced by FTIR, NMR and SEM results.•The results highlight the prospective use of Z. maritimum as a bioremediation tool.
Microplastics are persistent contaminants accumulating in the environment. Aquatic ecosystems have been studied worldwide, revealing ubiquitous contamination with microplastics. Microalgae, one of ...the most important primary producers in aquatic ecosystems, could suffer from microplastic contamination, leading to larger impacts on aquatic food webs. Nonetheless, little is known about the toxic effects of microplastics on microalgae populations. Thus, the objective of this review was to identify these effects and the impacts of microplastics on microalgae populations based on currently available literature, also identifying knowledge gaps. Even though microplastics seem to have limited effects on parameters such as growth, chlorophyll content, photosynthesis activity and reactive oxygen species (ROS), current environmental concentrations are not expected to induce toxicity. Even so, microplastics could disrupt population regulation mechanisms, by reducing the availability or absorption of nutrients (bottom-up) or reducing the population of predator species (top-down). Microplastics' properties can also influence the effects on microalgae, with smaller sizes and positive surface charges having higher toxicity. Therefore, more research is needed to better understand the effects of microplastics on microalgae, such as adaptation strategies, effects on population dynamics and microplastics properties influencing toxicity.
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•Microplastics' current concentrations are not expected to directly harm microalgae.•Microplastics may inhibit predation or reduce nutrient availability in microalgae.•Factors responsible for species sensitivity and microplastics toxicity are unclear.
Brain-derived neurotrophic factor (BDNF) belongs to a family of small secreted proteins that also include nerve growth factor, neurotrophin 3, and neurotrophin 4. BDNF stands out among all ...neurotrophins by its high expression levels in the brain and its potent effects at synapses. Several aspects of BDNF biology such as transcription, processing, and secretion are regulated by synaptic activity. Such observations prompted the suggestion that BDNF may regulate activity-dependent forms of synaptic plasticity such as long-term potentiation (LTP), a sustained enhancement of excitatory synaptic efficacy thought to underlie learning and memory. Here, we will review the evidence pointing to a fundamental role of this neurotrophin in LTP, especially within the hippocampus. Prominent questions in the field, including the release and action sites of BDNF during LTP, as well as the signaling and molecular mechanisms involved, will also be addressed. The diverse effects of BDNF at excitatory synapses are determined by the activation of TrkB receptors and downstream signaling pathways, and the functions, typically opposing in nature, of its immature form (proBDNF). The activation of p75
receptors by proBDNF and the implications for long-term depression will also be addressed. Finally, we discuss the synergy between TrkB and glucocorticoid receptor signaling to determine cellular responses to stress.
The mechanisms by which the pigment melanin is transferred from melanocytes and processed within keratinocytes to achieve skin pigmentation remain ill-characterized. Nevertheless, several models have ...emerged in the past decades to explain the transfer process. Here, we review the proposed models for melanin transfer in the skin epidermis, the available evidence supporting each one, and the recent observations in favor of the exo/phagocytosis and shed vesicles models. In order to reconcile the transfer models, we propose that different mechanisms could co-exist to sustain skin pigmentation under different conditions. We also discuss the limited knowledge about melanin processing within keratinocytes. Finally, we pinpoint new questions that ought to be addressed to solve the long-lasting quest for the understanding of how basal skin pigmentation is controlled. This knowledge will allow the emergence of new strategies to treat pigmentary disorders that cause a significant socio-economic burden to patients and healthcare systems worldwide and could also have relevant cosmetic applications.
•An innovative method of biomass pre-treatment using emimCH3COO was developed.•The valorization of biomass by the high purity biomass fraction samples.•Enzymatic hydrolysis showed high purity ...cellulose fractions.•Recovery and reuse of IL in a new pre-treatment process.
This work is devoted to study pre-treatment methodologies of wheat straw with 1-ethyl-3-methylimidazolium acetate (emimCH3COO) and subsequent fractionation to cellulose, hemicellulose and lignin. The method developed and described here allows the separation into high purity carbohydrate and lignin fractions and permits an efficient IL recovery. A versatility of the established method was confirmed by the IL reuse.
The fractionation of completely dissolved biomass led to cellulose-rich and hemicellulose-rich fractions. A high purity lignin was also achieved.
To verify the potential further applicability of the obtained carbohydrate-rich fractions, and to evaluate the pre-treatment efficiency, the cellulose fraction resulting from the treatment with emimCH3COO was subjected to enzymatic hydrolysis. Results showed a very high digestibility of the cellulose samples and confirmed a high glucose yield for the optimized pre-treatment methodology.
Abstract
Objectives
Lung involvement in RA has several manifestations and is a major cause of morbidity and mortality. The aim of this study was to characterize the different types of lung disease ...and response to treatment in a UK cohort of RA patients.
Methods
RA patients who had undergone high resolution CT scans of the lung were identified and scans reviewed. Demographic data, RA features, complementary exams and treatments were recorded for those with radiological evidence of lung involvement. Descriptive analysis was performed, and Mann–Whitney U and χ2 tests were used for comparison between different radiological subtypes.
Results
Lung disease was reported in 87 (7.7%) of 1129 RA patients, usually (97.7%) post-dating articular symptoms. Most patients had positive RF (74/84; 88.1%) and ACPA (72/82; 87.7%). Interstitial lung disease (ILD) was the most common pattern, reported in 45 (51.7%) patients. Drug-induced lung disease was reported in 2 of 64 (3.1%) patients treated with MTX. Rituximab was used in 26 (57.8%) patients with ILD, with evidence of disease improvement or stabilization in patients with non-specific interstitial pneumonia and organizing pneumonia. During lung disease follow-up (6.7 ± 4.1 years), 22 (25.3%) patients were admitted to hospital with respiratory infections, with 14 (63.6%) of them having underlying bronchiectasis. Lung disease-related mortality was estimated at 8%.
Conclusion
ILD was the most prevalent manifestation of lung involvement in RA and was associated with higher mortality. Immunosuppressive drugs used in RA were rarely associated with lung toxicity, and rituximab demonstrated promising results for the treatment of RA-ILD.
There has been a considerable increase on research of the ecological consequences of microplastics released into the environment, but only a handful of works have focused on the nano-sized particles ...of polymer-based materials. Though their presence has been difficult to adequately ascertain, due to the inherent technical difficulties for isolating and quantifying them, there is an overall consensus that these are not only present in the environment – either directly released or as the result of weathering of larger fragments – but that they also pose a significant threat to the environment and human health, as well. The reduced size of these particulates (<1μm) makes them susceptible of ingestion by organisms that are at the base of the food-chain. Moreover, the characteristic high surface area-to-volume ratio of nanoparticles may add to their potential hazardous effects, as other contaminants, such as persistent organic pollutants, could be adsorbed and undergo bioaccumulation and bioamplification phenomena.
In this review, we describe the most relevant sources of nanoplastics and offer some insights into their fate once released into the environment. Furthermore, we overview the most prominent effects of these small particulates, while identifying the key challenges scientists currently face in the research of nanoplastics in the environment. Lastly, we give a brief summary of the economic impacts of the pollution caused by plastic litter – a potential key source of nanoplastics – in the oceans, the most common destination of these contaminants.
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•There has been a considerable increase of research on the fate o nanosized plastics.•These can pose a significant threat to both the environment and human health.•We reviewed their sources, fates and effects.•We identified the key challenges researchers face in this field.•Insights into the future of nanoplastics-related research are presented.
Mild fractionation/pretreatment processes are becoming the most preferred choices for biomass processing within the biorefinery framework. To further explore their advantages, new developments are ...needed, especially to increase the extent of the hydrolysis of poly‐ and oligosaccharides. A possible way forward is the use of solid acid catalysts that may overcome many current drawbacks of other common methods. In this Review, the advantages and limitations of the use of heterogeneous catalysis for the main groups of solid acid catalysts (zeolites, resins, carbon materials, clays, silicas, and other oxides) and their relation to the hydrolysis of model soluble disaccharides and soluble poly‐ and oligosaccharides are presented and discussed. Special attention is given to the hydrolysis of hemicelluloses and hemicellulose‐derived saccharides into monosaccharides, the impact on process performance of potential catalyst poisons originating from biomass and biomass hydrolysates (e.g., proteins, mineral ions, etc.). The data clearly point out the need for studying hemicelluloses in natura rather than in model compound solutions that do not retain the relevant factors influencing process performance. Furthermore, the desirable traits that solid acid catalysts must possess for the efficient hemicellulose hydrolysis are also presented and discussed with regard to the design of new catalysts.
So solid catalyst: The hydrolysis of soluble poly/oligosaccharides increases the cost‐effectiveness of biomass upgrading within the biorefinery framework. Solid acid catalysts represent an advantageous green alternative to catalyze this reaction. This Review discusses the advantages and limitations of their use and identifies desirable characteristics in the design of future solid acid catalysts.
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