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Tourist volcanic caves are in high demand for ecotourism and geotourism lovers, as well as by sun and beach tourists as a complementary activity during their holidays. There are six tourist volcanic caves in the Canary Islands, all of them managed by the local administration of the island. The managers of these caves must ensure the safety of visitors and workers, who are exposed to natural hazards, such as radon, inherent to the environment in which the activity takes place. The methodology for analyzing natural radon radiation is based on the latest studies published by experts in this field and on previous experiences in tourist caves. This article proposes a protocol for the correct management of radon in tourist caves in the Canary Islands, adapted to current regulations, to mitigate effects on the health of visitors and workers.
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OBJECTIVES: Artificial intelligence (AI) tools are becoming more available in modern healthcare, particularly in radiology, although less attention has been paid to applications for children and young people. In the development of these, it is critical their views are heard. MATERIALS AND METHODS: A national, online survey was publicised to UK schools, universities and charity partners encouraging any child or young adult to participate. The survey was "live" for one year (June 2022 to 2023). Questions about views of AI in general, and in specific circumstances (e.g. bone fractures) were asked. RESULTS: One hundred and seventy-one eligible responses were received, with a mean age of 19 years (6-23 years) with representation across all 4 UK nations. Most respondents agreed or strongly agreed they wanted to know the accuracy of an AI tool that was being used (122/171, 71.3%), that accuracy was more important than speed (113/171, 66.1%), and that AI should be used with human oversight (110/171, 64.3%). Many respondents (73/171, 42.7%) felt AI would be more accurate at finding problems on bone X-rays than humans, with almost all respondents who had sustained a missed fracture strongly agreeing with that sentiment (12/14, 85.7%). CONCLUSIONS: Children and young people in our survey had positive views regarding AI, and felt it should be integrated into modern healthcare, but expressed a preference for a "medical professional in the loop" and accuracy of findings over speed. Key themes regarding information on AI performance and governance were raised and should be considered prior to future AI implementation for paediatric healthcare. CLINICAL RELEVANCE STATEMENT: Artificial intelligence (AI) integration into clinical practice must consider all stakeholders, especially paediatric patients who have largely been ignored. Children and young people favour AI involvement with human oversight, seek assurances for safety, accuracy, and clear accountability in case of failures. KEY POINTS: Paediatric patient's needs and voices are often overlooked in AI tool design and deployment. Children and young people approved of AI, if paired with human oversight and reliability. Children and young people are stakeholders for developing and deploying AI tools in paediatrics.
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An improved understanding of the pathobiology of Alzheimer's disease (AD) should lead ultimately to an earlier and more accurate diagnosis of AD, providing the opportunity to intervene earlier in the disease process and to improve outcomes. The known hallmarks of Alzheimer's disease include amyloid-ß plaques and neurofibrillary tau tangles. It is now clear that an imbalance between production and clearance of the amyloid beta protein and related Aß peptides, especially Aß42, is a very early, initiating factor in Alzheimer's disease (AD) pathogenesis, leading to aggregates of hyperphosphorylation and misfolded tau protein, inflammation, and neurodegeneration. In this article, we review how the AD diagnostic process has been transformed in recent decades by our ability to measure these various elements of the pathological cascade through the use of imaging and fluid biomarkers. The more recently developed plasma biomarkers, especially phosphorylated-tau217 (p-tau217), have utility for screening and diagnosis of the earliest stages of AD. These biomarkers can also be used to measure target engagement by disease-modifying therapies and the response to treatment.
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For the purpose of assessing human health exposure, it is necessary to characterize the toxins present in a given area and their potential impact on commercial species. The goal of this research study was: (1) to screen the prevalence and concentrations of lipophilic toxins in nine groups of marine invertebrates in the northwest Iberian Peninsula; (2) to evaluate the validity of wild mussels (Mytilus galloprovincialis) as sentinel organisms for the toxicity in non-bivalve invertebrates from the same area. The screening of multiple lipophilic toxins in 1150 samples has allowed reporting for the first time the presence of 13-desmethyl spirolide C, pinnatoxin G, okadaic acid, and dinophysistoxins 2 in a variety of non-traditional vectors. In general, these two emerging toxins showed the highest prevalence (12.5-75%) in most of the groups studied. Maximum levels for 13-desmethyl spirolide C and pinnatoxin G were found in the bivalves Magallana gigas (21 µg kg-1) and Tellina donacina (63 µg kg-1), respectively. However, mean concentrations for the bivalve group were shallow (2-6 µg kg-1). Okadaic acid and dinophysistoxin 2 with lower prevalence (1.6-44.4%) showed, on the contrary, very high concentration values in specific species of crustaceans and polychaetes (334 and 235 µg kg--1, respectively), to which special attention should be paid. Statistical data analyses showed that mussels could be considered good biological indicators for the toxicities of certain groups in a particular area, with correlations between 0.710 (for echinoderms) and 0.838 (for crustaceans). Polychaetes could be an exception, but further extensive surveys would be needed to draw definitive conclusions.
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Bivalves , Mytilus , Intoxicação por Frutos do Mar , Animais , Humanos , Ácido Okadáico/análise , Toxinas Marinhas/toxicidade , Toxinas Marinhas/análise , Frutos do Mar/análise , Intoxicação por Frutos do Mar/prevenção & controle , Cromatografia Líquida , Espectrometria de Massas em TandemRESUMO
INTRODUCTION: The prevalence of outcome reporting bias (ORB, i.e. selective reporting according to the results observed) across primary outcomes in randomised controlled trials (RCTs) including participants with stroke or transient ischaemic attack (TIA) is unknown. MATERIALS AND METHODS: We searched the Cochrane Database of Systematic Reviews on 3 February 2021 for reviews published 2008-2020 with at least one RCT of a therapeutic intervention, for participants with stroke or TIA, and a safety or efficacy outcome. We took a random sample of these RCTs and included those with a trial registry record or protocol published before reporting results. Two reviewers assessed discrepancies in outcome reporting across the trial registry record, protocol, statistical analysis plan, and publication for each RCT, using the classification system designed by the Outcome Reporting Bias in Trials group. RESULTS: Of 600 RCTs, we identified a trial registry record in 120 (20%), a protocol in 28 (5%), and a statistical analysis plan in 5 (1%) with 123 (21%) distinct RCTs being eligible for assessment: 110 (89%, 95% CI 83-94) were at no risk, 7 (6%, 95% CI 3-11) RCTs were at low risk, and 6 (5%, 95% CI 2-10) were at high risk of ORB. DISCUSSION: The prevalence of ORB in primary outcomes was low in stroke/TIA RCTs that were included in Cochrane reviews and had an identifiable trial registry record or protocol. Concerningly, we were unable to identify a trial registry record or protocol in most of our sample. CONCLUSION: Work is needed to further reduce ORB in stroke/TIA RCTs and explore the generalisability of these findings to RCTs outside of Cochrane reviews or without a registry record or protocol, as well as to secondary outcomes.
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Ataque Isquêmico Transitório , Acidente Vascular Cerebral , Humanos , Viés , Ataque Isquêmico Transitório/epidemiologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Acidente Vascular Cerebral/epidemiologiaRESUMO
Gymnodimine D (GYM D), 16-desmethyl gymnodimine D (16-desmethyl GYM D), and two tetrodotoxin analogues have been found in invertebrates obtained from the north Atlantic coast of Spain from May 2021 to October 2022. It is the first report of GYMD and 16-desmethyl GYM D in invertebrates worldwide and of the tetrodotoxin analogues, 5,6,11 trideoxy tetrodotoxin (5,6,11 trideoxy TTX) and its isomer (referred to as 5,6,11 trideoxy-epi-TTX), in the north Atlantic Coast of Spain. In this study, we also report for the first time the detection of tetrodotoxin (TTX) in three species (the cnidaria Calliactis parasitica, an unidentified species, and the bivalve Tellina donacina). The prevalence was medium for GYM D and 16-desmethyl GYM D and low for TTXs overall. The concentrations recorded were variable, with maximum values of GYM D in the bivalve Cerastoderma edule (8.8 µg GYM A equivalents kg-1), of 16-desmethyl GYM D in the bivalve Magellana gigas (10 µg GYM A equivalents kg-1) and of TTX and 5,6,11 trideoxy TTX in the cnidaria C. parasitica (49.7 and 233 µg TTX equivalents kg-1, respectively). There is very scarce information about these compounds. Therefore, the reporting of these new detections will increase the knowledge on the current incidence of marine toxins in Europe that the European Food Safety Authority (EFSA), in particular, and the scientific community, in general, have. This study also highlights the importance of analyzing toxin analogues and metabolites for effective monitoring programs and adequate health protection.
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Bivalves , Iminas , Animais , Tetrodotoxina , EspanhaRESUMO
Machine learning-based protein structure prediction algorithms, such as RosettaFold and AlphaFold2, have greatly impacted the structural biology field, arousing a fair amount of discussion around their potential role in drug discovery. While there are few preliminary studies addressing the usage of these models in virtual screening, none of them focus on the prospect of hit-finding in a real-world virtual screen with a model based on low prior structural information. In order to address this, we have developed an AlphaFold2 version where we exclude all structural templates with more than 30% sequence identity from the model-building process. In a previous study, we used those models in conjunction with state-of-the-art free energy perturbation methods and demonstrated that it is possible to obtain quantitatively accurate results. In this work, we focus on using these structures in rigid receptor-ligand docking studies. Our results indicate that using out-of-the-box Alphafold2 models is not an ideal scenario for virtual screening campaigns; in fact, we strongly recommend to include some post-processing modeling to drive the binding site into a more realistic holo model.
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Aprendizado Profundo , Conformação Proteica , Ligantes , Proteínas/química , Algoritmos , Ligação Proteica , Simulação de Acoplamento MolecularRESUMO
Therapy microencapsulation allows minimally invasive, safe, and effective administration. Hepatocyte growth factor (HGF) has angiogenic, anti-inflammatory, anti-apoptotic, and anti-fibrotic properties. Our objective was to evaluate the cardiac safety and effectiveness of intracoronary (IC) administration of HGF-loaded extended release microspheres in an acute myocardial infarction (AMI) swine model. An IC infusion of 5 × 106 HGF-loaded microspheres (MS+HGF, n = 7), 5 × 106 placebo microspheres (MS, n = 7), or saline (SAL, n = 7) was performed two days after AMI. TIMI flow and Troponin I (TnI) values were assessed pre- and post-treatment. Cardiac function was evaluated with magnetic resonance imaging (cMR) before injection and at 10 weeks. Plasma cytokines were determined to evaluate the inflammatory profile and hearts were subjected to histopathological evaluation. Post-treatment coronary flow was impaired in five animals (MS+HGF and MS group) without significant increases in TnI. One animal (MS group) died during treatment. There were no significant differences between groups in cMR parameters at any time (p > 0.05). No statistically significant changes were found between groups neither in cytokines nor in histological analyses. The IC administration of 5 × 106 HGF-loaded-microspheres 48 h post-AMI did not improve cardiac function, nor did it decrease inflammation or cardiac fibrosis in this experimental setting.
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Background: The existing World Health Organization (WHO) pneumonia case management guidelines rely on clinical symptoms and signs for identifying, classifying, and treating pneumonia in children up to 5 years old. We aimed to collate an individual patient-level data set from large, high-quality pre-existing studies on pneumonia in children to identify a set of signs and symptoms with greater validity in the diagnosis, prognosis, and possible treatment of childhood pneumonia for the improvement of current pneumonia case management guidelines. Methods: Using data from a published systematic review and expert knowledge, we identified studies meeting our eligibility criteria and invited investigators to share individual-level patient data. We collected data on demographic information, general medical history, and current illness episode, including history, clinical presentation, chest radiograph findings when available, treatment, and outcome. Data were gathered separately from hospital-based and community-based cases. We performed a narrative synthesis to describe the final data set. Results: Forty-one separate data sets were included in the Pneumonia Research Partnership to Assess WHO Recommendations (PREPARE) database, 26 of which were hospital-based and 15 were community-based. The PREPARE database includes 285 839 children with pneumonia (244 323 in the hospital and 41 516 in the community), with detailed descriptions of clinical presentation, clinical progression, and outcome. Of 9185 pneumonia-related deaths, 6836 (74%) occurred in children <1 year of age and 1317 (14%) in children aged 1-2 years. Of the 285 839 episodes, 280 998 occurred in children 0-59 months old, of which 129 584 (46%) were 2-11 months of age and 152 730 (54%) were males. Conclusions: This data set could identify an improved specific, sensitive set of criteria for diagnosing clinical pneumonia and help identify sick children in need of referral to a higher level of care or a change of therapy. Field studies could be designed based on insights from PREPARE analyses to validate a potential revised pneumonia algorithm. The PREPARE methodology can also act as a model for disease database assembly.
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Pneumonia , Masculino , Criança , Humanos , Lactente , Recém-Nascido , Pré-Escolar , Feminino , Pneumonia/tratamento farmacológico , Administração de Caso , Organização Mundial da Saúde , Algoritmos , PesquisaRESUMO
The presence of a 13-desmethyl Spirolide C isomer (Iso-13-desm SPX C) is very common in some infaunal mollusks in Galicia contaminated with this toxin. Its possible origin by biological transformation was investigated by incubating homogenates of the soft tissues of limpets and cockles spiked with 13-desmethyl Spirolide C (13-desm SPX C). The involvement of an enzymatic process was also tested using a raw and boiled cockle matrix. The enzymatic biotransformation of the parent compound into its isomer was observed in the two species studied, but with different velocities. The structural similarity between 13-desm SPX C and its isomer suggests that epimerization is the most likely chemical process involved. Detoxification of marine toxins in mollusks usually implies the enzymatic biotransformation of original compounds, such as hydroxylation, demethylation, or esterification; however, this is the first time that this kind of transformation between spirolides in mollusks has been demonstrated.
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Cardiidae , Gastrópodes , Animais , Patela , Moluscos , Alimentos Marinhos , BiotransformaçãoRESUMO
OBJECTIVE: To determine whether an artificial intelligence candidate could pass the rapid (radiographic) reporting component of the Fellowship of the Royal College of Radiologists (FRCR) examination. DESIGN: Prospective multi-reader diagnostic accuracy study. SETTING: United Kingdom. PARTICIPANTS: One artificial intelligence candidate (Smarturgences, Milvue) and 26 radiologists who had passed the FRCR examination in the preceding 12 months. MAIN OUTCOME MEASURES: Accuracy and pass rate of the artificial intelligence compared with radiologists across 10 mock FRCR rapid reporting examinations (each examination containing 30 radiographs, requiring 90% accuracy rate to pass). RESULTS: When non-interpretable images were excluded from the analysis, the artificial intelligence candidate achieved an average overall accuracy of 79.5% (95% confidence interval 74.1% to 84.3%) and passed two of 10 mock FRCR examinations. The average radiologist achieved an average accuracy of 84.8% (76.1-91.9%) and passed four of 10 mock examinations. The sensitivity for the artificial intelligence was 83.6% (95% confidence interval 76.2% to 89.4%) and the specificity was 75.2% (66.7% to 82.5%), compared with summary estimates across all radiologists of 84.1% (81.0% to 87.0%) and 87.3% (85.0% to 89.3%). Across 148/300 radiographs that were correctly interpreted by >90% of radiologists, the artificial intelligence candidate was incorrect in 14/148 (9%). In 20/300 radiographs that most (>50%) radiologists interpreted incorrectly, the artificial intelligence candidate was correct in 10/20 (50%). Most imaging pitfalls related to interpretation of musculoskeletal rather than chest radiographs. CONCLUSIONS: When special dispensation for the artificial intelligence candidate was provided (that is, exclusion of non-interpretable images), the artificial intelligence candidate was able to pass two of 10 mock examinations. Potential exists for the artificial intelligence candidate to improve its radiographic interpretation skills by focusing on musculoskeletal cases and learning to interpret radiographs of the axial skeleton and abdomen that are currently considered "non-interpretable."
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Inteligência Artificial , Bolsas de Estudo , Humanos , Estudos Prospectivos , Radiologistas , Radiografia , Estudos RetrospectivosRESUMO
The availability of AlphaFold2 has led to great excitement in the scientific communityâparticularly among drug huntersâdue to the ability of the algorithm to predict protein structures with high accuracy. However, beyond globally accurate protein structure prediction, it remains to be determined whether ligand binding sites are predicted with sufficient accuracy in these structures to be useful in supporting computationally driven drug discovery programs. We explored this question by performing free-energy perturbation (FEP) calculations on a set of well-studied protein-ligand complexes, where AlphaFold2 predictions were performed by removing all templates with >30% identity to the target protein from the training set. We observed that in most cases, the ΔΔG values for ligand transformations calculated with FEP, using these prospective AlphaFold2 structures, were comparable in accuracy to the corresponding calculations previously carried out using crystal structures. We conclude that under the right circumstances, AlphaFold2-modeled structures are accurate enough to be used by physics-based methods such as FEP in typical lead optimization stages of a drug discovery program.
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Aprendizado Profundo , Simulação de Dinâmica Molecular , Ligantes , Modelos Estruturais , Estudos Prospectivos , Ligação Proteica , Proteínas/química , TermodinâmicaRESUMO
Introducción: Twitter es la red social con más usuarios en la que la Federación de Asociaciones de Matronas de España (FAME) publica contenido, y al estudiar su cuenta, podemos explicar las características y funcionamiento de la FAME, además de comprender sus intereses a través del análisis de contenido de sus publicaciones. Metodología: Se realizó un estudio cualitativo etnográfico para describir y explicar los elementos que integran el sistema de la red social construida a través de twitter por la FAME, teniendo en cuenta su evolución, estructura e interacciones a través de los tweets publicados. Resultados: Se obtuvieron 358 tweets, clasificados en tres matrices de codificación relacionadas con: Asociaciones de Matronas de España, Menciones de la cuenta de twitter de la FAME y Categorías de los tweets de la FAME. Discusión: La actividad social en twitter fue intensa en los primeros años y escasa en los últimos debido a la pandemia por COVID-19 a diferencia de la mayoría de asociaciones científicas. La FAME utiliza su cuenta para difundir información relacionada con la salud de las mujeres y la visibilidad de las matronas relacionándola con temas de actualidad. Conclusiones: Debido a su creciente impacto, las redes sociales deberían servir como sistemas de información entre ciencia y sociedad, y los profesionales deben conocer y utilizar este tipo de herramientas. Es necesario contar con fuentes de información que reflejen la salud de las mujeres y la FAME demostró su conocimiento de este hecho a través de sus tweets publicados durante el periodo analizado. (AU)
Introduction: Twitter is the social network with the most users in which the Federation of Associations of Midwives of Spain (FAME) publishes content, and by studying your account, we can explain the characteristics and operation of FAME, in addition to understanding their interests through of the content analysis of your publications. Methodology: A qualitative ethnographic study was carried out to describe and explain the elements that make up the social network system built by FAME through twitter, taking into account its evolution, structure and interactions through the published tweets. Results: 358 tweets were obtained, classified in three coding matrices related to: Associations of Midwives of Spain, Mentions of the FAME twitter account and Categories of the FAME tweets. Discussion: Social activity on Twitter was intense in the first years and scarce in the last due to the COVID-19 pandemic, unlike most scientific associations. FAME uses its account to disseminate information related to women's health and the visibility of midwives, relating it to current issues. Conclusions: Due to their growing impact, social networks should serve as information systems between science and society, and professionals should know and use these types of tools. It is necessary to have sources of information that reflect the health of women and the FAME demonstrated its knowledge of this fact through its tweets published during the period analyzed. (AU)
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História do Século XXI , Rede Social , Mídias Sociais , Tocologia , Espanha , Sociedades , Disseminação de InformaçãoRESUMO
Neutrophilia and an elevated neutrophil:lymphocyte ratio are both characteristic features of severe COVID-19 infection. However, functional neutrophil responses have been poorly investigated in this setting. We utilised a novel PMA-based stimulation assay to determine neutrophil-derived reactive oxygen species (ROS) generation in patients with severe COVID-19 infection, non-COVID related sepsis and healthy study participants. ROS production was markedly elevated in COVID-19 patients with median values ninefold higher than in healthy controls and was particularly high in patients on mechanical ventilation. ROS generation correlated strongly with neutrophil count and elevated levels were also seen in patients with non-COVID related sepsis. Relative values, adjusted for neutrophil count, were high in both groups but extreme low or high values were seen in two patients who died shortly after testing, potentially indicating a predictive value for neutrophil function. Our results show that the high levels of neutrophils observed in patients with COVID-19 and sepsis exhibit functional capacity for ROS generation. This may contribute to the clinical features of acute disease and represents a potential novel target for therapeutic intervention.
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COVID-19 , Sepse , Humanos , Contagem de Leucócitos , Neutrófilos , Espécies Reativas de OxigênioRESUMO
The cockle Cerastoderma edule is a commercially important species in many European Countries. It can accumulate okadaic acid (OA) and other toxins in its group, which makes it unsuitable for human consumption, producing harvesting bans to avoid intoxications. The duration of those bans depends in part on the depuration kinetics of the toxin in this species. In this work, this kinetics was studied by means of fitting different models to depuration data experimentally obtained, using naturally contaminated cockles. Cockles depurated OA faster than most other bivalve species studied. Models that include Michaelis-Menten kinetics describe the depuration better than those using a first order exponential decrease to describe the first (or the only) compartment. One-compartment models were not able to describe the final part of the depuration curve, in which OA was depurated very slowly. Therefore, two-compartment models were needed. Esters were depurated at a much faster rate than the free form of the toxin; however, no significant esterification was detected during the process. The slow depuration rate suggests that other bivalve species could be used as sentinels to monitor cockle populations, but caution should be taken when toxin concentrations are very high.
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Bivalves , Cardiidae , Animais , Bivalves/metabolismo , Cardiidae/metabolismo , Esterificação , Europa (Continente) , Humanos , Ácido Okadáico/metabolismoRESUMO
The administration of cardiosphere-derived cells (CDCs) after acute myocardial infarction (AMI) is very promising. CDC encapsulation in alginate-poly-l-lysine-alginate (APA) could increase cell survival and adherence. The intrapericardial (IP) approach potentially achieves high concentrations of the therapeutic agent in the infarcted area. We aimed to evaluate IP therapy using a saline vehicle as a control (CON), a dose of 30 × 106 CDCs (CDCs) or APA microcapsules containing 30 × 106 CDCs (APA-CDCs) at 72 h in a porcine AMI model. Magnetic resonance imaging (MRI) was used to determine the left ventricular ejection fraction (LVEF), infarct size (IS), and indexed end diastolic and systolic volumes (EDVi; ESVi) pre- and 10 weeks post-injection. Programmed electrical stimulation (PES) was performed to test arrhythmia inducibility before euthanasia. Histopathological analysis was carried out afterwards. The IP infusion was successful in all animals. At 10 weeks, MRI revealed significantly higher LVEF in the APA-CDC group compared with CON. No significant differences were observed among groups in IS, EDVi, ESVi, PES and histopathological analyses. In conclusion, the IP injection of CDCs (microencapsulated or not) was feasible and safe 72 h post-AMI in the porcine model. Moreover, CDCs APA encapsulation could have a beneficial effect on cardiac function, reflected by a higher LVEF at 10 weeks.
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Prevalence and incidence of the marine toxins (paralytic, amnesic, and lipophilic toxins) including the so-called emerging toxins (these are, gymnodimines, pinnatoxins, or spirolides among others) have increased in recent years all over the world. Climate change, which is affecting the distribution of their producing phytoplankton species, is probably one of the main causes. Early detection of the toxins present in a particular area, and linking the toxins to their causative phytoplankton species are key tools to minimize the risk they pose for human consumers. The development of both types of studies requires fast and highly sensitive analytical methods. In the present work, we have developed a highly sensitive liquid chromatography-mass spectrometry methodology (LC-MS/MS), using a column with fused-core particle technology, for the determination of fourteen lipophilic toxins in a single run of 3.6 min. The performance of the method was evaluated for specificity, linearity, precision (repeatability and reproducibility) and accuracy by analysing spiked and naturally contaminated samples. The in-house validation was successful, and the limit of detection (LOD) and quantification (LOQ) for all the toxins were far below their regulatory action limits. The method is suitable to be considered in monitoring systems of bivalves for food control.
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Toxinas Marinhas/química , Frutos do Mar , Animais , Cromatografia Líquida , Humanos , Limite de Detecção , Intoxicação por Frutos do Mar/prevenção & controle , Espectrometria de Massas em TandemRESUMO
Cultures of the mussel Mytilus galloprovincialis are frequently affected by accumulation of the amnesic shellfish poisoning toxin domoic acid (DA). This species is characterized by a fast uptake and release of the toxin. In this work, the main characteristics of the uptake mechanism have been studied by incubation of digestive gland thin slices in media with different composition and DA concentration. DA uptake seems to follow Michaelis-Menten kinetics, with a very high estimated KM (1722 µg DA mL-1) and a Vmax of 71.9 µg DA g-1 h-1, which is similar to those found for other amino acids in invertebrates. Replacement of NaCl from the incubation media by Cl-choline (Na+-free medium) did not significantly reduce the uptake, but replacement by sorbitol (Na+-free and Cl--depleted medium) did. A new experiment replacing all chlorides with their equivalent gluconates (Na+- and Cl--free medium) showed an important reduction in the uptake that should be attributed to the absence of chloride, pointing to a Na+-independent, Cl- (or anion-) dependent transporter. In media with Na+ and Cl-, neither decreasing the pH nor adding cyanide (a metabolic inhibitor) had significant effect on DA uptake, suggesting that the transport mechanism is not H+- or ATP-dependent. In a chloride depleted medium, lowering pH or adding CN increased the uptake, suggesting that other anions could, at least partially, substitute chloride.
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Trato Gastrointestinal/metabolismo , Ácido Caínico/análogos & derivados , Mytilus/metabolismo , Animais , Cloretos/farmacologia , Cianetos/farmacologia , Gluconatos/farmacologia , Concentração de Íons de Hidrogênio , Ácido Caínico/farmacologia , Água do Mar/químicaRESUMO
Diabetes and metabolic syndrome are associated with the typical American high glycemia diet and result in accumulation of high levels of advanced glycation end products (AGEs), particularly upon aging. AGEs form when sugars or their metabolites react with proteins. Associated with a myriad of age-related diseases, AGEs accumulate in many tissues and are cytotoxic. To date, efforts to limit glycation pharmacologically have failed in human trials. Thus, it is crucial to identify systems that remove AGEs, but such research is scanty. Here, we determined if and how AGEs might be cleared by autophagy. Our in vivo mouse and C. elegans models, in which we altered proteolysis or glycative burden, as well as experiments in five types of cells, revealed more than six criteria indicating that p62-dependent autophagy is a conserved pathway that plays a critical role in the removal of AGEs. Activation of autophagic removal of AGEs requires p62, and blocking this pathway results in accumulation of AGEs and compromised viability. Deficiency of p62 accelerates accumulation of AGEs in soluble and insoluble fractions. p62 itself is subject to glycative inactivation and accumulates as high mass species. Accumulation of p62 in retinal pigment epithelium is reversed by switching to a lower glycemia diet. Since diminution of glycative damage is associated with reduced risk for age-related diseases, including age-related macular degeneration, cardiovascular disease, diabetes, Alzheimer's, and Parkinson's, discovery of methods to limit AGEs or enhance p62-dependent autophagy offers novel potential therapeutic targets to treat AGEs-related pathologies.