•Microplastics were present in atmospheric deposition in central London.•Comparing equal size classes, levels were 20 times greater than in a remote location.•Fibrous morphologies dominated and ...polyacrylonitrile was the most common polymer.•Local source areas influenced microplastic levels.
Microplastics are a global environmental issue contaminating aquatic and terrestrial environments. They have been reported in atmospheric deposition, and indoor and outdoor air, raising concern for public health due to the potential for exposure. Moreover, the atmosphere presents a new vehicle for microplastics to enter the wider environment, yet our knowledge of the quantities, characteristics and pathways of airborne microplastics is sparse. Here we show microplastics in atmospheric deposition in a major population centre, central London. Microplastics were found in all samples, with deposition rates ranging from 575 to 1008 microplastics/m2/d. They were found in various shapes, of which fibrous microplastics accounted for the great majority (92%). Across all samples, 15 different petrochemical-based polymers were identified. Bivariate polar plots indicated dependency on wind, with different source areas for fibrous and non-fibrous airborne microplastics. This is the first evidence of airborne microplastics in London and confirms the need to include airborne pathways when consolidating microplastic impacts on the wider environment and human health.
Macrophages activated by the Gram-negative bacterial product lipopolysaccharide switch their core metabolism from oxidative phosphorylation to glycolysis. Here we show that inhibition of glycolysis ...with 2-deoxyglucose suppresses lipopolysaccharide-induced interleukin-1β but not tumour-necrosis factor-α in mouse macrophages. A comprehensive metabolic map of lipopolysaccharide-activated macrophages shows upregulation of glycolytic and downregulation of mitochondrial genes, which correlates directly with the expression profiles of altered metabolites. Lipopolysaccharide strongly increases the levels of the tricarboxylic-acid cycle intermediate succinate. Glutamine-dependent anerplerosis is the principal source of succinate, although the 'GABA (γ-aminobutyric acid) shunt' pathway also has a role. Lipopolysaccharide-induced succinate stabilizes hypoxia-inducible factor-1α, an effect that is inhibited by 2-deoxyglucose, with interleukin-1β as an important target. Lipopolysaccharide also increases succinylation of several proteins. We therefore identify succinate as a metabolite in innate immune signalling, which enhances interleukin-1β production during inflammation.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Polyphenols are important components of plants, and contribute to colour, aroma and taste, as well as having many other functions. In recent years, considerable research has been conducted on ...polyphenols in foods, focusing on their bioavailability, metabolism and biological effects. This was driven by results of epidemiological studies which showed that diets rich in plant foods are associated with decreased incidence of cancer and heart diseases. Fruits are rich in polyphenols, and the extraction and enrichment of these bioactive compounds from fruit is of increasing academic and commercial interest.
In this review, the numerous approaches that have been investigated and utilised for the enrichment of polyphenols in foods over the last 20 years or so are discussed, mainly focusing on fruit-based products. This review summarises some important aspects of traditional polyphenol enrichment processes such as solvent extraction, as well as reviewing some novel approaches such as the use of colloidal gas aphrons and ohmic heating. Applications of each process are explained, advantages and disadvantages discussed, and recovery and enrichment levels of polyphenols presented.
Key findings and conclusions: Pre-treatments such as enzymatic hydrolysis, pulsed electric fields and high-pressure processing can be applied to fruit-based products to improve polyphenol extraction efficiency. There is high potential for the use of environmentally friendly processes for enrichment of polyphenols from fruit-based products using membrane filtration. Polyphenol enrichment technologies need to be cost-effective and rapid and facilitate retention of the biological activities of the polyphenols.
•Recovery of polyphenols is widely researched due to their potential applications.•The food industry requires clean and cost-effective polyphenol enrichment processes.•Membrane technology and pressurised liquid extraction are potentially exciting.•Solvent extraction has poor selectivity and generates solvent waste streams.•Pre-treatments, e.g., ohmic heating, can be used to improve extraction efficiency.
Patterns of species resource use provide insight into the functional roles of species and thus their ecological significance within a community. The functional role of herbivorous fishes on coral ...reefs has been defined through a variety of methods, but from a grazing perspective, less is known about the species-specific preferences of herbivores on different groups of reef algae and the extent of dietary overlap across an herbivore community. Here, we quantified patterns of redundancy and complementarity in a highly diverse community of herbivores at a reef on Maui, Hawaii, USA. First, we tracked fish foraging behavior in situ to record bite rate and type of substrate bitten. Second, we examined gut contents of select herbivorous fishes to determine consumption at a finer scale. Finally, we placed foraging behavior in the context of resource availability to determine how fish selected substrate type. All species predominantly (73–100 %) foraged on turf algae, though there were differences among the types of macroalgae and other substrates bitten. Increased resolution via gut content analysis showed the composition of turf algae consumed by fishes differed across herbivore species. Consideration of foraging behavior by substrate availability revealed 50 % of herbivores selected for turf as opposed to other substrate types, but overall, there were variable foraging portfolios across all species. Through these three methods of investigation, we found higher complementarity among herbivorous fishes than would be revealed using a single metric. These results suggest differences across species in the herbivore “rain of bites” that graze and shape benthic community composition.
In response to concerns about declining coral cover and recurring macroalgal blooms, in 2009 the State of Hawaii established the Kahekili Herbivore Fisheries Management Area (KHFMA). Within the ...KHFMA, herbivorous fishes and sea urchins are protected, but other fishing is allowed. As part of a multi-agency monitoring effort, we conducted surveys at KHFMA and comparison sites around Maui starting 19 months before closure, and over the six years since implementation of herbivore protection. Mean parrotfish and surgeonfish biomass both increased within the KHFMA (by 139% 95%QR (quantile range): 98-181% and 28% 95%QR: 3-52% respectively). Most of those gains were of small-to-medium sized species, whereas large-bodied species have not recovered, likely due to low levels of poaching on what are preferred fishery targets in Hawaii. Nevertheless, coincident with greater biomass of herbivores within the KHFMA, cover of crustose coralline algae (CCA) has increased from ~2% before closure to ~ 15% in 2015, and macroalgal cover has remained low throughout the monitoring period. Strong evidence that changes in the KHFMA were a consequence of herbivore management are that (i) there were no changes in biomass of unprotected fish families within the KHFMA; and that (ii) there were no similar changes in parrotfish or CCA at comparison sites around Maui. It is not yet clear how effective herbivore protection might eventually be for the KHFMA's ultimate goal of coral recovery. Coral cover declined over the first few years of surveys-from 39.6% (SE 1.4%) in 2008, to 32.9% (SE 0.8%) in 2012, with almost all of that loss occurring by 2010 (1 year after closure), i.e. before meaningful herbivore recovery had occurred. Coral cover subsequently stabilized and may have slightly increased from 2012 through early 2015. However, a region-wide bleaching event in 2015 had already led to some coral mortality by the time surveys were conducted in late 2015, at which time cover had dropped back to levels recorded in the KHFMA in 2012.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Field‐based cultivation of Kappaphycus and Eucheuma seaweeds is widespread across the tropics and is largely done to extract the polysaccharide carrageenan, which is used in commercial applications. ...Although such seaweed farming has been cited as a sustainable alternative livelihood to destructive fishing, there has not been a comprehensive review of its environmental impacts to assess its potential conservation benefit. We reviewed the peer‐reviewed and industry gray literature to determine what is known about seaweed farming techniques and their impacts on local ecosystems, organisms, and ecosystem services. We identified 43 tropical or subtropical countries that are currently cultivating or have cultivated carrageenophytes. Ecosystem impacts of seaweed farming were measured directly in 33 publications with variable results. Placement of seaweed farms above seagrass beds led to reduced productivity and shoot density in 5 studies and reduced or altered meiofaunal abundance and diversity in 6 studies. On coral reefs, overgrowth of corals by farmed seaweed species was documented in 8 cases. Two studies showed changes to herbivorous fish communities in adjacent areas because seaweed farms changed the environment, whereas in 2 studies measures of overall abundance or diversity did not change. The impacts of seaweed farming may not be as destructive as some other human activities, but they should still be considered when establishing new farms or managing existing farm sites. Our findings are consistent with suggestions to mitigate impact on local ecosystems by shifting seaweed farms to deeper, sandy‐bottom areas. However, some of these changes may adversely affect farmers and associated communities.
Impactos e Implicaciones Ambientales del Cultivo de Algas Marinas Carragenofitas Tropicales
Resumen
El cultivo de las algas marinas Kappaphycus y Eucheuma se encuentra distribuido extensamente en los trópicos y generalmente se realiza para extraer el polisacárido carragenano, el cual se usa en la industria comercial. Aunque se ha mencionado que dicho cultivo de algas marinas es una alternativa sustentable para la pesca destructiva como medio de subsistencia, no se ha realizado una revisión completa de sus impactos ambientales para evaluar su potencial beneficio de conservación. Analizamos la literatura gris y la revisada por pares sobre la industria para determinar qué se conoce sobre las técnicas de cultivo de algas marinas y sus impactos sobre los ecosistemas locales, organismos y servicios ambientales. Identificamos 43 países tropicales o subtropicales que actualmente cultivan o han cultivado carragenofitas. Medimos los impactos ambientales del cultivo de algas marinas de manera directa en 33 publicaciones con resultados variables. La colocación de granjas de algas marinas por encima de lechos de pasto marino derivó en una productividad reducida y en una densidad observada en cinco estudios. En seis estudios, esta colocación derivó en una reducción o alteración de la abundancia y diversidad de meiofauna. En los arrecifes de coral, se documentó en ocho casos la proliferación de corales por causa de las especies cultivadas de algas marinas. Dos estudios mostraron cambios en las comunidades de peces herbívoros de las áreas circundantes debido al cambio en el ambiente generado por los cultivos de algas marinas, mientras que, en otros dos estudios, las medidas de la abundancia o diversidad generalizadas no cambió. Los impactos del cultivo de algas marinas pueden no ser tan destructivos como otras actividades humanas, pero todavía deberían considerarse durante el establecimiento de nuevas granjas o durante el manejo de los sitios de cultivo existentes. Nuestros hallazgos van a la par de las sugerencias actuales para mitigar el impacto sobre los ecosistemas locales mediante la reubicación de las granjas de algas marinas a áreas más profundas con un lecho arenoso. Sin embargo, algunos de estos cambios podrían afectar negativamente a los cultivadores y a las comunidades asociadas.
Article impact statement: Tropical seaweed farming can negatively affect ecosystems, but shifting farms to deeper, sandy bottom areas can promote sustainability.
In patients with celiac disease, enteropathy is caused by the entry of gluten peptides into the lamina propria of the intestine, in which their immunogenicity is potentiated by tissue ...transglutaminase (tTG) and T-helper type 1-mediated immune responses are triggered. Tight junction disassembly and paracellular permeability are believed to have an important role in the transport of gluten peptides to the lamina propria. Larazotide acetate is a tight-junction regulator peptide that, in vitro, prevents the opening of intestinal epithelial tight junctions. The aim of this study was to evaluate the efficacy and tolerability of larazotide acetate in protecting against gluten-induced intestinal permeability and gastrointestinal symptom severity in patients with celiac disease.
In this dose-ranging, placebo-controlled study, 86 patients with celiac disease controlled through diet were randomly assigned to larazotide acetate (0.25, 1, 4, or 8 mg) or placebo three times per day with or without gluten challenge (2.4 g/day) for 14 days. The primary efficacy outcome was the urinary lactulose/mannitol (LAMA) fractional excretion ratio. Secondary endpoints included gastrointestinal symptom severity, quality-of-life measures, and antibodies to tTG.
LAMA measurements were highly variable in the outpatient setting. The increase in LAMA ratio associated with the gluten challenge was not statistically significantly greater than the increase in the gluten-free control. Among patients receiving the gluten challenge, the difference in the LAMA ratios for the larazotide acetate and placebo groups was not statistically significant. However, larazotide acetate appeared to limit gluten-induced worsening of gastrointestinal symptom severity as measured by the Gastrointestinal Symptom Rating Scale at some lower doses but not at the higher dose. Symptoms worsened significantly in the gluten challenge-placebo arm compared with the placebo-placebo arm, suggesting that 2.4 g of gluten per day is sufficient to induce reproducible gluten toxicity. Larazotide acetate was generally well tolerated. No serious adverse events were observed. The most common adverse events were headache and urinary tract infection.
LAMA variability in the outpatient setting precluded accurate assessment of the effect of larazotide acetate on intestinal permeability. However, some lower doses of larazotide acetate appeared to prevent the increase in gastrointestinal symptom severity induced by gluten challenge.
Stroke patients are at increased risk of falls and fractures. The aim of this study was to determine the rate, predictors and consequences of falls within 2 years after stroke in a prospective ...population-based study in North Dublin, Ireland.
Prospective population-based cohort study.
567 adults aged >18 years from the North Dublin Population Stroke Study.
Participants were enrolled from an Irish urban population of 294,592 individuals, according to recommended criteria. Patients were followed for 2 years. Outcome measures included death, modified Rankin Scale (mRS), fall and fracture rate.
At 2 years, 23.5% (124/522) had fallen at least once since their stroke, 14.2% (74/522) had 2 or more falls and 5.4% (28/522) had a fracture. Of 332 survivors at 2 years, 107 (32.2%) had fallen, of whom 60.7% (65/107) had 2 or more falls and 23.4% (25/107) had fractured. In a multivariable model controlling for age and gender, independent risk factors for falling within the first 2 years of stroke included use of alpha-blocker medications for treatment of hypertension (P = 0.02). When mobility measured at Day 90 was included in the model, patients who were mobility impaired (mRS 2-3) were at the highest risk of falling within 2 years of stroke odds ratio (OR) 2.30, P = 0.003 and those functionally dependent (mRS 4-5) displayed intermediate risk (OR 2.02, P = 0.03) when compared with independently mobile patients.
Greater attention to falls risk, fall prevention strategies and bone health in the stroke population are required.
The development of a pronounced iliotibial band (ITB) is an anatomically distinct evolution of humans. The mechanical behaviour of this “new” structure is still poorly understood and hotly debated in ...current literature. Iliotibial band syndrome (ITBS) is one of the leading causes of lateral knee pain injuries in runners. We currently lack a comprehensive understanding of the healthy behaviour of the ITB, and this is necessary prior to further investigating the aetiology of pathologies like ITBS. Therefore, the purpose of this narrative review was to collate the anatomical, biomechanical and clinical literature to understand how the mechanical function of the ITB is influenced by anatomical variation, posture and muscle activation. The complexity of understanding the mechanical function of the ITB is due, in part, to the presence of its two in-series muscles: gluteus maximus (GMAX) and tensor fascia latae (TFL). At present, we lack a fundamental understanding of how GMAX and TFL transmit force through the ITB and what mechanical role the ITB plays for movements like walking or running. While there is a range of proposed ITBS treatment strategies, robust evidence for effective treatments is still lacking. Interventions that directly target the running biomechanics suspected to increase either ITB strain or compression of lateral knee structures may have promise, but clinical randomised controlled trials are still required.
Electric energy harvesting mediated by atmospheric humidity was first demonstrated in 2010, followed by the description of different approaches by many authors. Moisture-based energy-harvesting ...devices usually contain metals and/or are fabricated using nanomaterials and lithographic processes. Here we present a flexible energy harvesting device that is an asymmetric capacitor, formed by two electrodes made out of Kraft paper coated with exfoliated and reassembled graphite (ERG). The electrodes are doped with different chemicals and finished using standard papermaking processes. The voltage output of a single ERG-based hygroelectric generator (ERG-HEG) cell is as high as 0.5 V and it can deliver 250 nA of electric current through a 2 MΩ resistor, for days. The voltage and current outputs can be scaled up by connecting ERG-HEGs in series or parallel. Energy harvesting is also achieved by short (5 seconds) cyclic capacitor charge/discharge extending for more than two weeks. Examinaton of the electrodes during their operation, using Kelvin probe and microscopy analysis, showed that negative charge carriers are the main actors in the ERG-HEG devices. The low material cost, the simple fabrication processes and the energy output invite further development and scaling-up of this "green" alternative for producing electricity.
Converting humidity into useful electrical energy was only recently demonstrated and the improvements presented in this work are not only highly energy efficient, but also contributes to the development of scalable, real-world applications.
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