An overview of the contaminant mixtures present in key consumed fish and seafood species along the Portuguese territory.

This study evaluates the concentrations of potentially toxic elements - mercury, arsenic, cadmium, lead and selenium - in seven marine species (Xiphias gladius, Aphanopus carbo, Merluccius merluccius, Helicolenus dactylopterus, Loligo vulgaris, Cancer pagurus and Ruditapes decussatus) across different locations in mainland Portugal and the Azores. The results showed a significant interaction between species and site, indicating that elemental concentrations varied by species and sampling site. This highlights the complex interplay of biological and environmental factors, such as habitat, feeding habits and local sources of contamination.

Decreasing mercury concentrations in beaks of the giant warty squid Moroteuthopsis longimana in the Scotia Sea (Southern Ocean) since the 1970s.

The giant warty squid Moroteuthopsis longimana is an important prey of top predators in the Southern Ocean. It is therefore a major link in the pathway of contaminants like mercury (Hg) to higher levels in food webs. In this study, we evaluated changes in Hg concentrations in beaks of adult M.

Spatial and interspecific differences of trace element concentrations in the feathers of pelagic and coastal seabirds from the Northeast Atlantic Ocean and the Western Mediterranean Sea.

Coastal ecosystems face increasing contamination threats due to urbanisation and consequent human pressure worldwide. This study assessed exposure to 15 trace elements (Al, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se, Sr, Ti, V, Zn) across the Northeast Atlantic and the western Mediterranean in pelagic shearwaters (Calonectris borealis and C. diomedea) and coastal gulls (Ichthyaetus audouinii and Larus michahellis).

Calonectris shearwaters reveal a gradient of mercury contamination along the Atlantic and Mediterranean waters of the Iberian Peninsula.

This study examines blood mercury (Hg) concentrations in Calonectris spp. shearwaters from three colonies along the Atlantic and Mediterranean waters of the Iberian Peninsula (southwestern Europe), investigating their relationship with foraging ecology through GPS tracking and stable isotopes (δN and δC) data during the breeding season. Hg levels exhibited a spatial gradient, increasing from the Atlantic Ocean (1.

Squid beaks as a proxy for mercury concentrations in muscle of the giant warty squid Moroteuthopsis longimana.

Cephalopods play a major role in marine food webs as both predators and prey. Although most of the Hg in cephalopods is present in the muscle, most studies on its accumulation by predators are based on concentrations in beaks. Here, using upper and lower beaks and buccal masses of Moroteuthopsis longimana, we evaluated the relationship between Hg concentrations in different cephalopod tissues.

Restoration of degraded estuarine and marine ecosystems: A systematic review of rehabilitation methods in Europe.

This article provides a comprehensive study of ecosystem rehabilitation methods widely used in the 21st century, focusing on Europe. The review covers the evolution and trends in scientific article publication, identification of European countries demonstrating high publication outputs, collaboration patterns, leading journals, and thematic areas. Additionally, it examines primary stressors in European aquatic ecosystems, and different methods and treatments commonly employed for remediation purposes.

Using seagrass as a nature-based solution: Short-term effects of Zostera noltei transplant in benthic communities of a European Atlantic coastal lagoon.

Seagrass meadows provide several ecological functions that improve the overall ecological health of coastal systems and therefore, it is urgent to promote the restoration of such habitats. In Ria de Aveiro, a coastal lagoon in the Atlantic Coast of Portugal, a restoration initiative was responsible for transplanting the dwarf eelgrass Zostera noltei into a highly degraded area. This eelgrass was used as a nature-based solution (NbS) to mitigate some of the impacts of historical mercury contamination.

The Digital Twin Paradigm Applied to Soil Quality Assessment: A Systematic Literature Review.

This article presents the results regarding a systematic literature review procedure on digital twins applied to precision agriculture. In particular, research and development activities aimed at the use of digital twins, in the context of predictive control, with the purpose of improving soil quality. This study was carried out through an exhaustive search of scientific literature on five different databases.

Are mercury levels in fishery products appropriate to ensure low risk to high fish-consumption populations?

The main goal of the present study is to determine the sources of methylmercury (MeHg) for high fish-consumption populations with the Portuguese population as showcase, as Portugal is the EU country with the highest fish consumption per capita (2019: 59.91 kg year). Since limited information is available on the effective levels of mercury after culinary treatments, cooked and raw codfish (Gadus morhua), hake (Merluccius merluccius), octopus (Octopus vulgaris), horse mackerel (Trachurus trachurus) and sardine (Sardina pilchardus) were considered.

Intramembrane client recognition potentiates the chaperone functions of calnexin.

One-third of the human proteome is comprised of membrane proteins, which are particularly vulnerable to misfolding and often require folding assistance by molecular chaperones. Calnexin (CNX), which engages client proteins via its sugar-binding lectin domain, is one of the most abundant ER chaperones, and plays an important role in membrane protein biogenesis. Based on mass spectrometric analyses, we here show that calnexin interacts with a large number of nonglycosylated membrane proteins, indicative of additional nonlectin binding modes.

Lifelong mercury bioaccumulation in Atlantic horse mackerel (Trachurus trachurus) and the potential risks to human consumption.

Atlantic horse mackerel is one of the most commercially important species in Europe. It can reach a longevity of 30 years, with potential implications in lifespan mercury contamination. This study conducted along the Portuguese coast aimed at evaluating the total Hg content and tissue distribution, to determine the annual mercury bioaccumulation patterns and the associated risk for consumption.

Oxidative stress, metabolic activity and mercury concentrations in Antarctic krill Euphausia superba and myctophid fish of the Southern Ocean.

Indicators of oxidative stress and metabolic capacity are key factors in understanding the fitness of wild populations. In the present study, these factors were evaluated in the pelagic Southern Ocean taxa Antarctic krill (Euphausia superba) and myctophid fish (Electrona antarctica, Gymnoscopelus braueri and G. nicholsi) to establish a baseline record for future studies.

Mercury biomagnification in a Southern Ocean food web.

Biomagnification of mercury (Hg) in the Scotia Sea food web of the Southern Ocean was examined using the stable isotope ratios of nitrogen (δN) and carbon (δC) as proxies for trophic level and feeding habitat, respectively. Total Hg and stable isotopes were measured in samples of particulate organic matter (POM), zooplankton, squid, myctophid fish, notothenioid fish and seabird tissues collected in two years (austral summers 2007/08 and 2016/17). Overall, there was extensive overlap in δC values across taxonomic groups suggesting similarities in habitats, with the exception of the seabirds, which showed some differences, possibly due to the type of tissue analysed (feathers instead of muscle).

Cephalopod beak sections used to trace mercury levels throughout the life of cephalopods: The giant warty squid Moroteuthopsis longimana as a case study.

Cephalopods represent an important pathway for mercury transfer through food webs. Due to the general difficulties in capturing oceanic squid, beaks found in the diet of top predators can be used to study their life-cycles and ecological role. Using upper beaks of the giant warty squid Moroteuthopsis longimana (major prey in the Southern Ocean), we describe a method to assess mercury concentrations along the life of cephalopods through the segmentary analysis of beak sections (i.

Multiple regression analysis to assess the contamination with metals and metalloids in surface sediments (Aveiro Lagoon, Portugal).

An innovative multiple regression analysis was used to evaluate metal/metalloid contamination in the surface sediments of a coastal lagoon. The concentrations of metals/metalloids were represented as a function of geochemical characteristics of the sediments (fine fraction, concentrations of organic carbon, Ca, Al, Mn) and distances between sampling points. The effect of distances on the concentrations were negligible for Li, Co, Ni, Ba, V, Cr, and only geochemical variables specific for each element explained its spatial variation.

Main drivers of mercury levels in Southern Ocean lantern fish Myctophidae.

Myctophids are the most abundant fish group in the Southern Ocean pelagic ecosystem and are an important link in the Antarctic marine food web. Due to their major ecological role, evaluating the level of mercury (Hg) contamination in myctophids is important as a step towards understanding the trophic pathway of this contaminant. The concentrations of total Hg were determined in muscle, gill, heart and liver tissue of 9 myctophid species to quantify tissue partitioning variability between species.

High mercury levels in Antarctic toothfish Dissostichus mawsoni from the Southwest Pacific sector of the Southern Ocean.

Mercury is a bioaccumulating toxic pollutant which can reach humans through the consumption of contaminated food (e.g. marine fish).

In case of stress, hold tight: phosphorylation switches PDI from an oxidoreductase to a holdase, tuning ER proteostasis.

Eukaryotic cells have evolved multiple responses that allow endoplasmic reticulum (ER) homeostasis to be maintained even in the face of acute or chronic stresses. In this issue, Yu et al (2020) describe how site-specific phosphorylation switches protein disulfide isomerase (PDI) from a folding enzyme to a holdase chaperone which regulates ER stress responses, thus highlighting PDI as a key player in ER homeostasis.

Mercury accumulation in fish species along the Portuguese coast: Are there potential risks to human health?

This paper aimed at evaluating the total mercury content in five common fish species from the western European Atlantic coastal waters, and the associated risk of consumption. Mercury concentrations in muscle of Atlantic mackerel (Scomber scombrus), Atlantic chub mackerel (Scomber colias), European anchovy (Engraulis encrasicolus), Atlantic horse mackerel (Trachurus trachurus) and European pilchard (Sardina pilchardus) ranged from 0.003 to 0.

Mercury levels in Southern Ocean squid: Variability over the last decade.

The concentrations of total and proportions of organic mercury were measured in tissues of 355 individuals of 8 species of Southern Ocean squid (Alluroteuthis antarcticus, Bathyteuthis abyssicola, Filippovia knipovitchi, Galiteuthis glacialis, Gonatus antarcticus, Kondakovia longimana, Psychroteuthis glacialis and Slosarczykovia circumantarctica). Squid were caught around South Georgia (Scotia Sea) during 5 cruises, between the austral summers of 2006/07 to 2016/17 to evaluate temporal changes in bioaccumulation and tissue partitioning. Total mercury concentrations varied between 4 ng g and 804 ng g among all tissues.

Mechanistic Insights into Statistical Co-Assembly of Metal Complexes.

Statistical copolymerization plays a key role in many biological and technological processes; however, mechanistic understanding of the formation of analogous supramolecular counterparts remains limited. Herein, we report detailed insights into the supramolecular co-assembly of two π-conjugated Pd and Pt complexes, which in isolation self-assemble into flexible fibers and nanodisks, respectively. An efficient single-step co-assembly into only one type of nanostructure (fibers or nanodisks) takes place if any of the components is in excess.

Spatial variability in total and organic mercury levels in Antarctic krill Euphausia superba across the Scotia Sea.

Total and organic mercury concentrations were determined for males, females and juveniles of Euphausia superba collected at three discrete locations in the Scotia Sea (South Orkney Islands, South Georgia and Antarctic Polar Front) to assess spatial mercury variability in Antarctic krill. There was clear geographic differentiation in mercury concentrations, with specimens from the South Orkney Islands having total mercury concentrations 5 to 7 times higher than Antarctic krill from South Georgia and the Antarctic Polar Front. Mercury did not appear to accumulate with life-stage since juveniles had higher concentrations of total mercury (0.

A carefully designed nanoplatform based on multi walled carbon nanotube wrapped with aptamers.

The interaction between carbon nanotubes (CNTs) and biological molecules of diagnostic and therapeutic interest, as well as the internalization of the CNTs-biomolecules complexes in different types of cell, has been extensively studied due to the potential use of these nanocomplexes as multifunctional nanoplatforms in a great variety of biomedical applications. The effective use of these nanobiotechnologies requires broad multidisciplinary studies of biocompatibility, regarding, for example, the in vitro and in vivo nanotoxicological assays, the capacity to target specific cells and the evaluation of their biomedical potential. However, the first step to be reached is the careful obtainment of the nanoplatform and the understanding of the actual surface composition and structural integrity of the complex system.

New climatic targets against global warming: will the maximum 2 °C temperature rise affect estuarine benthic communities?

The Paris Agreement signed by 195 countries in 2015 sets out a global action plan to avoid dangerous climate change by limiting global warming to remain below 2 °C. Under that premise, in situ experiments were run to test the effects of 2 °C temperature increase on the benthic communities in a seagrass bed and adjacent bare sediment, from a temperate European estuary. Temperature was artificially increased in situ and diversity and ecosystem functioning components measured after 10 and 30 days.

Carcinogenesis in rats subjected to a new model ureterosigmoidostomy and treated with L-lysine.

Purpose:: To evaluate the effects of L-lysine on the intestinal and urothelial epithelium of rats subjected to ureterosigmoidostomy (new model for surgical carcinogenesis).

Methods:: Forty-two rats, 9 weeks of age, were divided into 6 groups. Animals in groups A, B, C were subjected to ureterosigmoidostomy (US) and treated with L-lysine, celecoxib and H2O, respectively.