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1.
J Xenobiot ; 14(3): 1165-1186, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39311145

RESUMO

The presence of anthropogenic compounds, including organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs), was studied in three salt marshes within the Tagus estuary, Portugal, along an anthropogenic pressure gradient. Results revealed differences in OCPs and PCBs among the marshes, with differing concentration levels. Specifically, one marsh, with surrounding agricultural activity, showed the highest OCP concentrations, while another, with a historical industrial past, exhibited elevated PCB levels. In contrast, a third marsh, part of a natural reserve, displayed comparatively lower concentrations of both substances. Sediment concentrations, likely influenced by agricultural practices, were found to be comparable to or higher than those observed in other Portuguese estuaries. The halophyte Spartina maritima was found to absorb OCPs, particularly in its aboveground tissues, suggesting bioaccumulation within the plant. Additionally, PCB levels appeared to be influenced by industrial history, with one marsh displaying notably higher concentrations. In conclusion, the persistence of organochlorine compounds in the salt marsh ecosystems notwithstanding the regulatory prohibitions implemented in the 1990s highlights the need for continuous monitoring and study of such sites and the necessity of remediation practices, which are imperative to mitigate ecological and health risks in these polluted salt marshes.

2.
Mar Pollut Bull ; 207: 116806, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39128231

RESUMO

Estuaries are among the most sensitive systems to climate change. Previous studies have suggested that the Sado Estuary (Portugal) has decreasing trends for water temperature, which is uncommon in a global warming scenario. However, no long-term analysis regarding water column conditions has been conducted on this estuary to date. Therefore, the main aim of this study is to understand if and how the properties of this estuary have changed, considering a 34-year trend analysis and an assessment of their main drivers. Water temperature significantly decreased (up to 0.04 °C/year) along with chlorophyll a. Salinity increased and nutrients displayed an overall decrease. These trends were potentially driven by higher influence of upwelled water combined with a reduction of the river flow. Sado appears to have a lower vulnerability to climate change than other estuaries as it does not show a high sensitivity to changes in its water column physicochemical properties.


Assuntos
Mudança Climática , Monitoramento Ambiental , Estuários , Rios , Temperatura , Rios/química , Portugal , Salinidade , Clorofila A , Clorofila/análise , Movimentos da Água
3.
Foods ; 13(10)2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38790834

RESUMO

Environmental degradation leads to an unsustainable food system. In addition to this issue, the consumption of foods that improve people's health and well-being is recommended. One of the alternatives is undoubtedly the use of by-products of winemaking, namely in the form of grape pomace flour (GPF). To verify the benefits of using the Touriga Nacional and Arinto (Vitis vinifera L.) flour varieties, analytical determinations were made to identify and quantify different components. In terms of nutritional characterization, the Touriga Nacional GPF showed results that indicate better nutritional quality than the Arinto GPF. The Touriga Nacional and Arinto samples had protein contents of 10.13% and 8.38%, polyunsaturated fatty acids of 6.66% and 5.18%, soluble dietary fiber of 14.3% and 1.7%, and insoluble dietary fiber of 55.1% and 46.4%, respectively. The anthocyanins, proanthocyanidins, and flavonols presented in samples were detected by HPLC-DAD/ESI-MS. Atomic absorption spectrometry revealed elevated concentrations of certain elements in Touriga Nacional compared to Arinto, with the former showing higher levels of aluminum (130 mg/kg) and iron (146 mg/kg) against the latter's Al (120 mg/kg) and Fe (112 mg/kg) content. GPF could become a valuable ingredient due to its nutritional quality and high content of various polyphenols.

4.
Viruses ; 16(4)2024 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-38675840

RESUMO

The ability of recombinant, SARS-CoV-2 Spike (S) protein to modulate the production of two COVID-19 relevant, pro-inflammatory cytokines (IL-6 and IFN-γ) in PBMC cultures of healthy, pre-COVID-19 subjects was investigated. We observed that cytokine production was largely and diversely modulated by the S protein depending on antigen or mitogen stimulation, as well as on the protein source, insect (S-in) or human (S-hu) cells. While both proteins co-stimulated cytokine production by polyclonally CD3-activated T cells, PBMC activation by the mitogenic lectin Concanavalin A (Con A) was up-modulated by S-hu protein and down-modulated by S-in protein. These modulatory effects were likely mediated by the S glycans, as demonstrated by direct Con A-S binding experiments and use of yeast mannan as Con A binder. While being ineffective in modulating memory antigenic T cell responses, the S proteins and mannan were able to induce IL-6 production in unstimulated PBMC cultures and upregulate the expression of the mannose receptor (CD206), a marker of anti-inflammatory M2 macrophage. Our data point to a relevant role of N-glycans, particularly N-mannosidic chains, decorating the S protein in the immunomodulatory effects here reported. These novel biological activities of the S glycan ectodomain may add to the comprehension of COVID-19 pathology and immunity to SARS-CoV-2.


Assuntos
COVID-19 , Interleucina-6 , Lectinas Tipo C , Leucócitos Mononucleares , Receptor de Manose , Lectinas de Ligação a Manose , Receptores de Superfície Celular , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Humanos , Glicoproteína da Espícula de Coronavírus/metabolismo , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/genética , Lectinas Tipo C/metabolismo , Receptores de Superfície Celular/metabolismo , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/imunologia , COVID-19/imunologia , COVID-19/virologia , COVID-19/metabolismo , SARS-CoV-2/imunologia , SARS-CoV-2/metabolismo , Lectinas de Ligação a Manose/metabolismo , Interleucina-6/metabolismo , Citocinas/metabolismo , Interferon gama/metabolismo , Células Cultivadas , Polissacarídeos/metabolismo , Voluntários Saudáveis , Linfócitos T/imunologia , Linfócitos T/metabolismo , Ativação Linfocitária , Concanavalina A/metabolismo
5.
J Leukoc Biol ; 115(6): 1053-1069, 2024 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-38242866

RESUMO

Tuberculosis is one of the deadliest infectious diseases worldwide. Mycobacterium tuberculosis has developed strategies not only to evade host immunity but also to manipulate it for its survival. We investigated whether Mycobacterium tuberculosis exploited the immunogenicity of Ag85B, one of its major secretory proteins, to redirect host antituberculosis immunity to its advantage. We found that administration of Ag85B protein to mice vaccinated with Bacillus Calmette-Guérin impaired the protection elicited by vaccination, causing a more severe infection when mice were challenged with Mycobacterium tuberculosis. Ag85B administration reduced Bacillus Calmette-Guérin-induced CD4 T-cell activation and IFN-γ, CCL-4, and IL-22 production in response to Mycobacterium tuberculosis-infected cells. On the other hand, it promoted robust Ag85B-responsive IFN-γ-producing CD4 T cells, expansion of a subset of IFN-γ/IL-10-producing CD4+FOXP3+Treg cells, differential activation of IL-17/IL-22 responses, and activation of regulatory and exhaustion pathways, including programmed death ligand 1 expression on macrophages. All this resulted in impaired intracellular Mycobacterium tuberculosis growth control by systemic immunity, both before and after the Mycobacterium tuberculosis challenge. Interestingly, Mycobacterium tuberculosis infection itself generated Ag85B-reactive inflammatory immune cells incapable of clearing Mycobacterium tuberculosis in both unvaccinated and Bacillus Calmette-Guérin-vaccinated mice. Our data suggest that Mycobacterium tuberculosis can exploit the strong immunogenicity of Ag85B to promote its own survival and spread. Since Ag85B is normally secreted by replicating bacteria and is commonly found in the lungs of the Mycobacterium tuberculosis-infected host, our findings may advance the understanding on the mechanisms of Mycobacterium tuberculosis pathogenesis and immune evasion.


Assuntos
Aciltransferases , Antígenos de Bactérias , Vacina BCG , Proteínas de Bactérias , Camundongos Endogâmicos C57BL , Mycobacterium tuberculosis , Tuberculose , Animais , Camundongos , Aciltransferases/imunologia , Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Vacina BCG/imunologia , Linfócitos T CD4-Positivos/imunologia , Citocinas/metabolismo , Viabilidade Microbiana , Mycobacterium tuberculosis/imunologia , Tuberculose/imunologia , Tuberculose/microbiologia
6.
Environ Sci Technol ; 57(27): 10062-10069, 2023 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-37382470

RESUMO

Microplastics (MP) have been found in various environments worldwide. However, not many studies focus on the open ocean due to logistical restraints. Between January and May 2020, the NRP Sagres sampled 123 linear paths of subsurface water of the Atlantic Ocean, passing by Cape Verde, the east coast of South America, and the west coast of Africa. The water was sampled through the ship's water system. The membranes were analyzed by the Hydrographic Institute of Portugal and the Norwegian Institute for Water Research by micro-FTIR. The contamination levels were reported with uncertainty, for 99% confidence level (CL), normalized for filtered water volume and the distance traveled during sampling. Uncertainties were calculated through a detailed ″bottom-up″ evaluation. MP were found in about a third of the stations (48 out of 123), and most of those stations (43 out of 48) presented concentrations below 1 m-3 km-1. The sites where higher concentrations were registered were the port of the island of Santiago (Cape Verde) ((5.9 ± 5.2) m-3 km-1), the Guanabara Bay in Rio de Janeiro (Brazil) ((41 ± 27) m-3 km-1), and close to South Africa ((4.9 ± 2.4) m-3 km-1). Most MP found were polyamide, polyester, polyethylene, ethylene vinyl acetate, and poly(methyl methacrylate). The estimated contamination levels cannot be directly compared with information obtained in other studies due to differences in how MP were determined and the unknown uncertainty of their measured values. This article presents a relevant and reliable contribution to understanding the MP distribution in the Atlantic Ocean.


Assuntos
Microplásticos , Poluentes Químicos da Água , Plásticos , Incerteza , Brasil , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Água
7.
Sci Total Environ ; 887: 163930, 2023 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-37156391

RESUMO

The comparison of oil patterns of a spill (Sp) and suspected spill source (SS) samples is based on ratios between correlated GC-MS signals of oil-discriminating compounds, i.e., diagnostic ratios (DR). The Student's t statistics (S-t) and a maximum relative difference (SC), proposed in standard methods, have been used for DR comparison due to their simplicity. An alternative methodology based on Monte Carlo Method (MCM) simulations of correlated signals, capable of accurately defining DR comparison criteria, proved that S-t and SC assumptions regarding DR normality and precision are frequently not valid, affecting comparison reliability. The performance of the approaches was accurately compared from independent signals of the same oil sample from a perfect match between Sp and SS. The present study describes the comparison of the approaches in real oil spill scenarios reproduced in International Round Robin Tests. Since as the number of compared DR increases, also rises the probability of not all equivalent DR being actually considered equivalent, the decision of oil pattern equivalence was based on two comparisons of independent sets of Sp and SS signals. The risk of true oil standard equivalency claims is compared for the three oil spill scenarios studied, which are different considering oil types, DR sets and spill weathering. The ability of the approaches to distinguish the Sp sample from an oil sample known not to be the source of the spill was also assessed. The MCM based on two independent DR comparison trials was the only one consistently producing fingerprint comparison risks of correct equivalence claims larger than 98 %. MCM also performed better in distinguishing different oil patterns. It was concluded that comparing >22 DR does not change the risk of correct oil pattern equivalence assessment significantly. The complexity of the MCM approach is overcome by using user-friendly and validated software.

8.
Rev Med Inst Mex Seguro Soc ; 61(2): 251-255, 2023 Mar 01.
Artigo em Espanhol | MEDLINE | ID: mdl-37200622

RESUMO

Background: The indiscriminate application of substances for aesthetic purposes, such as silicone in breast implants, leads to the production of common local signs such as inflammation, skin irregularities, edema, erythema, vascular neoformations, and ulcers, which can evolve into general symptoms such as fever, asthenia, weakness, arthralgia or activate the immune system abnormally, causing the appearance of autoimmune diseases. This set of signs and symptoms is called adjuvant-induced autoimmune/inflammatory syndrome. Clinical case: We present the case of a 50-year-old woman with a history of silicone-based breast implants who spontaneously developed a hemorrhagic coagulopathy, type A acquired hemophilia was documented, that is, autoantibodies against coagulation factor VIII. Thanks to the work of a multidisciplinary team, it is possible to successfully diagnose and treat the patient with bridging agents, implant removal and management of associated symptoms. Conclusion: the importance of knowing the pathology is recognized, which, although it is rare, when it occurs has a high mortality rate if it is not diagnosed and treated on time.


Introducción: la aplicación de sustancias con fines estéticos de forma indiscriminada, como es el caso de la silicona en los implantes mamarios, llevan a la producción de signos locales comunes como: inflamación, irregularidad en la piel, edema, eritema, neoformaciones vasculares y úlceras, que pueden evolucionar a síntomas generales como la fiebre, astenia, adinamia, artralgias o a activar, de manera anómala, el sistema inmunitario, causando la aparición de enfermedades autoinmunitarias. A este conjunto de signos y síntomas se le denomina síndrome autoinmunitario/inflamatorio inducido por adyuvantes. Caso clínico: presentamos el caso de una mujer de 50 años con antecedente de implantes mamarios a base de silicona que desarrolla, de manera espontánea, una coagulopatía hemorrágica, se documenta hemofilia tipo A adquirida, es decir, autoanticuerpos contra el factor VIII de la coagulación. Gracias al trabajo de un equipo multidisciplinario se consigue diagnosticar y tratar de manera exitosa a la paciente con agentes de puente, remoción de los implantes y manejo de los síntomas asociados. Conclusión: se reconoce la importancia de conocer la patología que, si bien es rara, cuando se presenta tiene alta tasa de mortalidad si no se diagnostica y trata a tiempo.


Assuntos
Doenças Autoimunes , Implantes de Mama , Feminino , Humanos , Pessoa de Meia-Idade , Implantes de Mama/efeitos adversos , Síndrome , Doenças Autoimunes/diagnóstico , Doenças Autoimunes/etiologia , Inflamação/complicações , Adjuvantes Imunológicos/efeitos adversos , Silicones/efeitos adversos
9.
Sci Total Environ ; 884: 163612, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37100132

RESUMO

Small plastic particles, designated as microplastics, are known vehicles of several contaminants desorbed from their surface after being ingested by marine organisms. The monitoring of the levels and trends of microplastics in oceanic areas is essential to identify relevant threats and respective sources whose management should be improved to protect the environmental resources. However, the assessment of contamination trends in large oceanic areas is affected by contamination heterogeneity, sampling representativeness, and the uncertainty of collected sample analyses. Only contamination variations not justifiable by system heterogeneity and their characterisation uncertainty are meaningful and should be taken seriously by the authorities. This work describes a novel methodology for the objective identification of meaningful variation of microplastic contamination in vast oceanic areas by the Monte Carlo simulation of all uncertainty components. This tool was successfully applied to the monitoring of the levels and trends of microplastic contamination in sediments from a 700 km2 oceanic area from 3 km to 20 km offshore Sesimbra and Sines (Portugal). This work allowed concluding that contamination has not varied between 2018 and 2019 (difference of mean total microplastic contamination between -40 kg-1 and 34 kg-1) but that microparticles made of PET are the major type of studied microplastics (in 2019, mean contamination is between 36 kg-1 and 85 kg-1). All assessments were performed for a 99 % confidence level.


Assuntos
Microplásticos , Poluentes Químicos da Água , Plásticos/análise , Incerteza , Poluentes Químicos da Água/análise , Sedimentos Geológicos , Monitoramento Ambiental
10.
Chemosphere ; 323: 138216, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36822520

RESUMO

Sea cucumbers are indicators of metal contamination in sea bottoms due to their low mobility and feeding behaviour. Comparing contaminations of specimens from different locations, habitats, and/or organs allows understanding of contamination processes and differences. However, the interpretation of these data is affected by the variability of contamination levels in specimens, the uncertainty of tissue analyses, and the complex correlation of mass fractions estimated by using the same calibration of the used instrumental method of analysis. This work presents a novel tool for the sound comparison of contamination levels of biota where all mentioned factors are considered to produce reliable and undisputable information on the studied system. The Monte Carlo simulation of uncertainty components, affecting the determination of mean contamination levels observed in selected types of tissues, allowed simulating mean contamination differences and determining if these are meaningful. This tool was used to assess the levels of Cd, Cu, Ni and Pb of animals collected in different locations of Sesimbra-Portugal. It was concluded that specimens that selectively consume macroalgae have larger contamination levels than animals feeding on sediment. The gut is the most contaminated organ suggesting intake from feeding is dominant. Three of the analysed animals have Pb mass fractions larger than a maximum admissible value for human consumption of 3 mg kg-1 with a probability larger than 2.5%.


Assuntos
Metais Pesados , Pepinos-do-Mar , Oligoelementos , Poluentes Químicos da Água , Animais , Humanos , Metais Pesados/análise , Chumbo/análise , Sedimentos Geológicos/análise , Poluentes Químicos da Água/análise , Ecossistema , Oligoelementos/análise , Monitoramento Ambiental/métodos
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