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The prevalence of adrenal incidentalomas (i.e., incidental findings) has grown in recent years with the evolution of imaging methods. Adrenal masses can be benign or malignant. Malignant ones are less frequent, but the detection of primary adrenal neoplasms is even less frequent, especially in the case of a diffuse large B-cell lymphoma (DLBCL). This case concerns a 68-year-old man who presented to the emergency department due to fatigue and anorexia. Given his blood test results on admission, he underwent a computed tomography (CT) with angiography that identified a mass in the left adrenal gland with displacement of the ipsilateral kidney. Left tumorectomy, adrenalectomy, and nephrectomy were performed, and the mass corresponded to a nongerminal center-type DLBCL. This case highlights the importance of prompt diagnosis and surgical and pharmacologic treatment of DLBCL.
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There has been an intense focus to uncover the molecular mechanisms by which fasting triggers the adaptive cellular responses in the major organs of the body. Here, we show that in mice, hepatic S-adenosylmethionine (SAMe)-the principal methyl donor-acts as a metabolic sensor of nutrition to fine-tune the catabolic-fasting response by modulating phosphatidylethanolamine N-methyltransferase (PEMT) activity, endoplasmic reticulum-mitochondria contacts, ß-oxidation, and ATP production in the liver, together with FGF21-mediated lipolysis and thermogenesis in adipose tissues. Notably, we show that glucagon induces the expression of the hepatic SAMe-synthesizing enzyme methionine adenosyltransferase α1 (MAT1A), which translocates to mitochondria-associated membranes. This leads to the production of this metabolite at these sites, which acts as a brake to prevent excessive ß-oxidation and mitochondrial ATP synthesis and thereby endoplasmic reticulum stress and liver injury. This work provides important insights into the previously undescribed function of SAMe as a new arm of the metabolic adaptation to fasting.
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Neoplasias Hepáticas , S-Adenosilmetionina , Camundongos , Animais , S-Adenosilmetionina/metabolismo , Fígado/metabolismo , Neoplasias Hepáticas/metabolismo , Jejum , Trifosfato de Adenosina/metabolismo , Metionina Adenosiltransferase/metabolismo , Fosfatidiletanolamina N-Metiltransferase/metabolismoRESUMO
INTRODUCTION: The standard treatment for intrahepatic cholangiocarcinoma (iCCA) and mixed hepatocellular-cholangiocarcinoma (HCC-CC) is surgical resection, nevertheless, recent studies show adequate survival rates in selected patients with iCCA or HCC-CC undergoing liver transplantation (LT). METHODS: A retrospective cohort study was design including all patients undergoing LT at our center between January, 2006 and December, 2019 with incidentally diagnosed iCCA or HCC-CC after pathological examination of the explanted liver (n = 13). RESULTS: There were no iCCA or HCC-CC recurrences during the follow-up, and hence, there were no tumor related deaths. Global and disease-free survival were the same. The 1, 3 and 5-years patient survival were 92.3%, 76.9% and 76.9%, respectively. Survival rates in the "early-stage tumor group" at 1, 3 and 5 years were 100%, 83.3% and 83.3%, respectively, with no significant differences as compared to the "advanced-stage tumors group". No statistically significant differences in terms of 5-year survival were found when comparing tumor histology (85.7% for iCCA and 66.7% for HCC-CC). CONCLUSIONS: These results suggest that LT could be an option in patients with chronic liver disease who develop an iCCA or HCC-CC, even in highly selected advanced tumors, but we must be cautious when analyzing these results because of the small sample size of the series and its retrospective nature.
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Neoplasias dos Ductos Biliares , Carcinoma Hepatocelular , Colangiocarcinoma , Neoplasias Hepáticas , Transplante de Fígado , Humanos , Carcinoma Hepatocelular/cirurgia , Carcinoma Hepatocelular/patologia , Estudos Retrospectivos , Seguimentos , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/patologia , Transplante de Fígado/métodos , Resultado do Tratamento , Neoplasias dos Ductos Biliares/diagnóstico , Colangiocarcinoma/cirurgia , Ductos Biliares Intra-Hepáticos/patologiaRESUMO
Minimally invasive anatomical sublobar resections have gained relevance in recent years mainly due to advances in imaging techniques, screening programs and the increase in second neoplasms. Accurate identification of the segmental or subsegmental bronchus is vital to guarantee optimal results in segmentectomies and subsegmentectomies. Given the complexity and the possibility of anatomical variations, several authors have published different methods to identify the target bronchus. However, these methods have certain limitations. This article describes a new rapid and effective technique, with a low risk of complications and without additional cost, for the identification of segmental bronchi in minimally invasive segmentectomies.
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Pneumonectomia , Procedimentos Cirúrgicos Robóticos , Humanos , Pneumonectomia/métodos , Mastectomia Segmentar , Fluorescência , Brônquios/diagnóstico por imagem , Brônquios/cirurgia , Procedimentos Cirúrgicos Robóticos/métodosRESUMO
The relevance of minor transcription start sites in broad promoters is not well understood. We have studied AGAP2 expression in prostate cancer and chronic myeloid leukemia (CML), showing transcription is initiated from alternative transcription start sites (TSSs) within a single TSS cluster, producing cancer-type-specific AGAP2 mRNAs with small differences in their 5' UTR length. Interestingly, in the CML cell lines where the 5' UTR is longer, AGAP2 protein levels are lower. We demonstrate that the selection of an upstream TSS involved the formation of a G quadruplex in the 5' UTR, decreasing polysome formation. After developing a bioinformatics pipeline to query data from the FANTOM project and the NCl-60 human tumor cell lines screen, we found HK1 expression can also be regulated by the same mechanism. Overall, we present compelling data supporting TSS selection within a TSS cluster play a role in protein expression and should not be ignored.
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G quadruplex structures play an important role in regulating DNA replication and transcription and mRNA translation. Although there are several techniques that can determine its formation in vitro, the study of RNA G quadruplexes in vivo is not simple. In the current protocol, we describe an optimized technique (RNA G quadruplex immunoprecipitation [rG4IP]) to selectively pull down native cytoplasmic RNAs containing G quadruplex structures in mammalian cells. We also use a bicistronic plasmid to confirm and pinpoint the structure location. For complete details on the use and execution of this protocol, please refer to Surani et al. (2022).
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Quadruplex G , Animais , Imunoprecipitação , Mamíferos/genética , Biossíntese de Proteínas , RNA/genéticaRESUMO
A 48-year-old woman with no history of cardiovascular risk factors was admitted to the emergency room with complaints of angor, dyspnea, and fever in the last 24 h. She was referred for xerostomia and xerophthalmia since 2015. At examination, the patient was polypneic with bibasal crackles. Blood tests showed leukocytosis and increased high sensitivity troponin I and C-reactive protein (CRP). The echocardiogram revealed a small pericardial effusion. She was diagnosed with myopericarditis and started acetylsalicylic acid (ASA) and colchicine. Laboratory tests indicated the presence of positive antinuclear antibodies, double-strain DNA antibodies (anti-dsDNA), anti-Sjögren's-syndrome-related antigen A (anti-SSA), and lupus anticoagulant antibodies. Positivity for phase II immunoglobulin M and G for Coxiella burnetti was detected. As it fulfills the diagnostic criteria for a possible flare of systemic lupus erythematosus (SLE) and SS (triggered by a possible infection by C. burnetti) the patient started immunosuppressive therapy. A complete resolution of symptoms with normalization of CRP and troponin I values were observed.
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We here studied some potential factors underlying variation in compliance with preventive behaviors against COVID-19 by studying mask wearing during outdoor recreational activities in a midsize city of Argentina in 2020. The originality of present research relies on the complementation of observational (N = 15,507) and survey (N = 578) data and in assessing the determinants of and disposition to the same preventive behavior across activities. In Study 1, we did 8 weeks of unobtrusive systematic observation of mask wearing in outdoor recreational sites as a function of activity (walking, running, and cycling). In Study 2, we ran an online survey (concomitant with the last weeks of the observational study) to measure self-reported mask use and relevant beliefs, including self- and other-regarding motives. Behavioral observations showed that mask wearing declined over time for the three activities as predicted from a social dilemma perspective; nonetheless, compliance significantly differed across activities. Self-reported mask use was predicted by the perceived risk of contagion for the self and for others, perceived comfort costs of wearing masks, and social norms, but not by perceived illness severity or mask effectiveness. We discuss some implications and limitations of present findings for the development of preventive strategies to reduce COVID-19 transmission.
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COVID-19 , Humanos , Máscaras , Pandemias , SARS-CoV-2 , Inquéritos e QuestionáriosRESUMO
This study analyses international student mobility (ISM) in Europe since the 1999 Bologna Declaration. International mobility of higher education students is both a driver and a consequence of the Bologna Process and emerges as a relevant issue in a wide range of research areas. This literature review develops a qualitative content analysis of the set of high-performance articles published between 2000 and 2018 and identified through a wide range of bibliometric tools: direct (first generation) citation counts; indirect or accumulated impact; early influence; adjusted impact with respect to year of publication, type of document, and discipline; and alternative metrics that measure interactions in the internet and social media. The content analysis focuses on the pending achievements and main challenges to ISM, among them: attracting non-European students to whole degree programs, the need for actual and further convergence in programs and systems to ensure real compatibility, the impact of HE ISM on the promotion of the European citizenship and consciousness, the sharp imbalance between credit and degree mobility, the need to strengthen the link between ISM and employability, the existing social selectivity in European ISM, the frequent social segregation problems faced by international students.
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BACKGROUND: Pylephlebitis is a rare condition, poorly recognized by clinicians and with few references. In this case, the clinical appearance resembled the clinical course of a pancreatic cancer and was originated by the ingestion of a fish bone, making the case more interesting and rare. CASE SUMMARY: A 79-year-old female presented to the emergency department with fever, loss of appetite and jaundice. Tenderness in the right upper quadrant was present. Inflammation marker were high. A computed tomography (CT) scan revealed gallstones and aspects compatible with acute pancreatitis. The patient was admitted to surgery ward and has her condition aggravated. A magnetic resonance revealed multifocal liver lesions. Later, a cholangiopancreatography and an endoscopic ultrasound (US) were able to diagnose the condition. Specific treatment was implemented and the patient made a complete recovery. CONCLUSION: In conclusion, this case report demonstrates for the first time the diagnosis of an unusual case of pylephlebitis complicated by the migration of a fish bone, mimicking metastatic pancreatic cancer. Clinical presentation and traditional imaging studies, such as transabdominal US and CT, remain the standard for diagnosing this condition.
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The endocytosis of ligand-bound receptors and their eventual recycling to the plasma membrane (PM) are processes that have an influence on signalling activity and therefore on many cell functions, including migration and proliferation. Like other tyrosine kinase receptors (TKR), the insulin receptor (INSR) has been shown to be endocytosed by clathrin-dependent and -independent mechanisms. Once at the early endosome (EE), the sorting of the receptor, either to the late endosome (LE) for degradation or back to the PM through slow or fast recycling pathways, will determine the intensity and duration of insulin effects. Both the endocytic and the endosomic pathways are regulated by many proteins, the Arf and Rab families of small GTPases being some of the most relevant. Here, we argue for a specific role for the slow recycling route, whilst we review the main molecular mechanisms involved in INSR endocytosis, sorting and recycling, as well as their possible role in cell functions.
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Endossomos/metabolismo , Receptor de Insulina/metabolismo , Animais , Proteínas de Transporte , Membrana Celular/metabolismo , Movimento Celular , Proliferação de Células , Clatrina/metabolismo , Endocitose , Humanos , Lisossomos , Ligação Proteica , Transporte Proteico , Receptor de Insulina/agonistas , Vesículas Transportadoras/metabolismo , Proteínas rab de Ligação ao GTP/metabolismoRESUMO
Cell synchronization is crucial when studying events that take place at specific points of the cell cycle. Several chemical agents can be used to achieve the cell culture synchronization but not all type of cells respond equally to a given concentration of these drugs. Here we describe a simple optimization method to select concentrations and timings for nocodazole or thymidine treatments using fluorescence staining. In addition, we provide detailed protocols to arrest an asynchronous culture of either suspension or adherent cells in G1/S or in G2/M.
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Técnicas de Cultura de Células/métodos , Nocodazol/farmacologia , Timidina/farmacologia , Adesão Celular , Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Corantes Fluorescentes/química , Células HeLa , Humanos , Fatores de TempoRESUMO
Breast sarcomas are a rare group of malignant tumors accounting for less than 1% of all malignant neoplasms of the breast and fewer than 5% of all sarcomas. We report a case of an 87-year-old caucasian female who recurred to the emergency department with complaints of a painful mass of the left breast with purulent discharge. Observation revealed a volumous mass in the inferior quadrants of the breast, ill defined, with petrous consistency, areas of necrosis, and inflammatory signs. She was admitted to Surgery ward for further study and therapy of a probable inflammatory tumor of the breast. Magnetic resonance image was obtained, raising suspicion on papillary carcinoma and classified the breast as BIRADS5. Microbiological and cytological exams of the exudate were negative. An incisional biopsy of the tumoral mass was also obtained, and the patient discharged while waiting for surgery. Histological exam and immunohistochemical essay were compatible with leiomyosarcoma. Left mastectomy was performed and the patient was discharged with no morbidities on the 5th day after surgery. Histological exam of mastectomy piece showed a metaplastic carcinoma, with osteosarcomatous and focal leiomyosarcomatous differentiation. The lesion was classified as pT4N0M0 and subsequent radiotherapy was performed. Twenty months after surgery the patient was being followed-up on Oncology and Senology consultations and remained asymptomatic. Consensus on ideal management of this diseases is still on debate. Some authors defend the treatment of this entity in a similar way to sarcoma of the breast. More studies are needed to better understand this entity.
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AGAP2 (Arf GAP with GTP-binding protein-like domain, Ankyrin repeat and PH domain 2) isoform 2 is a protein that belongs to the Arf GAP (GTPase activating protein) protein family. These proteins act as GTPase switches for Arfs, which are Ras superfamily members, being therefore involved in signaling regulation. Arf GAP proteins have been shown to participate in several cellular functions including membrane trafficking and actin cytoskeleton remodeling. AGAP2 is a multi-tasking Arf GAP that also presents GTPase activity and is involved in several signaling pathways related with apoptosis, cell survival, migration, and receptor trafficking. The increase of AGAP2 levels is associated with pathologies as cancer and fibrosis. Transforming growth factor beta-1 (TGF-ß1) is the most potent pro-fibrotic cytokine identified to date, currently accepted as the principal mediator of the fibrotic response in liver, lung, and kidney. Recent literature has described that the expression of AGAP2 modulates some of the pro-fibrotic effects described for TGF-ß1 in the liver. The present review is focused on the interrelated molecular effects between AGAP2 and TGFß1 expression, presenting AGAP2 as a new player in the signaling of this pro-fibrotic cytokine, thereby contributing to the progression of hepatic fibrosis.
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Proteínas de Ligação ao GTP/metabolismo , Proteínas Ativadoras de GTPase/metabolismo , Células Estreladas do Fígado/metabolismo , Cirrose Hepática/metabolismo , Transdução de Sinais/genética , Fator de Crescimento Transformador beta1/metabolismo , Diferenciação Celular/genética , Movimento Celular/genética , Proliferação de Células/genética , Proteínas de Ligação ao GTP/genética , Proteínas Ativadoras de GTPase/genética , Células Estreladas do Fígado/enzimologia , Humanos , Cirrose Hepática/enzimologia , Cirrose Hepática/genética , Isoformas de Proteínas/metabolismo , Transporte Proteico/genética , Fator de Crescimento Transformador beta1/genéticaRESUMO
The growing popularity of physical sunscreens will lead to an increased release of ingredients from zinc oxide (ZnO) sunscreens into marine environments. Though zinc (Zn) is a necessary micronutrient in the ocean, greater than natural Zn concentrations may be released into marine environments by use of sunscreens. The extent of the consequences of this addition of Zn to the ocean are not fully understood. We investigated the effects of materials released by ZnO- sunscreens on the development of California purple sea urchin, Strongylocentrotus purpuratus. Embryos incubated in various concentrations of Zn (0.01, 0.05, 0.1, 0.5, and 1â¯mg/L), the sources of which included zinc-containing compounds: ZnO and zinc sulfate (ZnSO4); and ZnO sunscreens: All Good, Badger, and Raw Elements brands. Based on EC50 values, ZnO-containing sunscreens were slightly, but not significantly, more toxic than ZnO and ZnSO4, suggesting that sunscreens may release additional unknown materials that are detrimental to sea urchin embryo development. All concentrations of Zn-exposure resulted in significant malformations (skeletal abnormality, stage arrest, axis determination disruption), which were identified using light and fluorescence confocal microscopy. The concentration of Zn2+ internalized by the developing embryos correlated positively with the concentration of Zn in seawater. Additionally, exposure to both ZnO sunscreens and ZnO and ZnSO4 at 1â¯mg/L Zn, significantly increased calcein-AM (CAM) accumulation, indicating decreased multidrug resistant (MDR) transporter activity. This is one of the first studies documenting ZnO-containing sunscreens release high concentrations of Zn that are internalized by and have detrimental effects on aquatic organisms.
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Desenvolvimento Embrionário/efeitos dos fármacos , Strongylocentrotus purpuratus/efeitos dos fármacos , Protetores Solares/uso terapêutico , Poluentes Químicos da Água/toxicidade , Óxido de Zinco/toxicidade , Sulfato de Zinco/toxicidade , Animais , Organismos Aquáticos/efeitos dos fármacos , Organismos Aquáticos/crescimento & desenvolvimento , Fluoresceínas/metabolismo , Água do Mar/química , Strongylocentrotus purpuratus/embriologiaRESUMO
The Kinematic Theory of rapid movements and its associated Sigma-Lognormal model have been extensively used in a large variety of applications. While the physical and biological meaning of the model have been widely tested and validated for rapid movements, some shortcomings have been detected when it is used with continuous long and complex movements. To alleviate such drawbacks, and inspired by the motor equivalence theory and a conceivable visual feedback, this paper proposes a novel framework to extract the Sigma-Lognormal parameters, namely iDeLog. Specifically, iDeLog consists of two steps. The first one, influenced by the motor equivalence model, separately derives an initial action plan defined by a set of virtual points and angles from the trajectory and a sequence of lognormals from the velocity. In the second step, based on a hypothetical visual feedback compatible with an open-loop motor control, the virtual target points of the action plan are iteratively moved to improve the matching between the observed and reconstructed trajectory and velocity. During experiments conducted with handwritten signatures, iDeLog obtained promising results as compared to the previous development of the Sigma-Lognormal.
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The study aimed to analyze barriers in access to health services in five Health Regions of Brazil. The study analyzed the answers to semi-structured questionnaires applied to health policymakers, providers, and professionals from the Brazilian Unified National Health System, referenced on the following dimensions: Geographic Accessibility, Availability, and Acceptability. The analysis pointed to specificities in barriers to access in the five regions, while others such as location and time spent to reach the service were barriers in nearly all of them, based on care for stroke patients. In terms of Availability, there were issues related to shortage of physicians, long waiting time, and integration among services in all the regions. As for Acceptability, the study highlighted users' belief that they have no health problems. The Health Regions located in South and Southeast Brazil showed the fewest and least variety of barriers, revealing the persistence of regional inequalities. Although the results do not represent the country as a whole, they allow identifying relevant issues for regionalization of the national health system.
O objetivo foi analisar as barreiras de acesso aos serviços de saúde existentes em cinco Regiões de Saúde do Brasil. Foram analisadas as respostas obtidas a partir da aplicação de questionários semiestruturados a gestores, prestadores e, em número mais restrito, a profissionais de saúde do Sistema Único de Saúde, tendo como referência as dimensões: Acessibilidade Geográfica, Disponibilidade e Aceitabilidade. Foram verificadas as especificidades em relação às barreiras de acesso nas regiões consideradas, já outras como a localização e tempo gasto no trajeto foram barreiras em quase todas elas quando foi considerado o cuidado ao acidente vascular cerebral. Quando à Disponibilidade, foram observadas questões relacionadas à insuficiência de médicos, tempo de espera prolongado e problemas relativos à integração, em todas as regiões. Quanto à Aceitabilidade, destacou-se a crença dos usuários de não possuir problemas de saúde. As Regiões de Saúde situadas no Sul e Sudeste do país registraram menor quantidade e diversidade de barreiras, revelando a persistência de desigualdades regionais. Embora os resultados não representem o conjunto do Brasil, permitem apontar questões relevantes sobre o processo de regionalização do sistema de saúde no país.
El objetivo fue analizar las barreras de acceso a los servicios de salud existentes en cinco Regiones de Salud de Brasil. Se analizaron las respuestas obtenidas a partir de la aplicación de cuestionarios semiestructurados a gestores, prestadores y, en número más restringido, a profesionales de salud del Sistema Único de Salud, teniendo como referencia las dimensiones: Accesibilidad Geográfica, Disponibilidad y Aceptabilidad. Se verificaron especificidades en relación con las barreras de acceso en las regiones consideradas, mientras otras como la localización y el tiempo invertido en el trayecto, fueron barreras en casi todas ellas, cuando se consideró el cuidado a un accidente vascular cerebral. En cuanto a la Disponibilidad, se observaron cuestiones relacionadas con la insuficiencia de médicos, tiempo de espera prolongado y problemas relativos a la integración, en todas las regiones. En cuanto a la Aceptabilidad, se destacó la creencia de los usuarios de no poseer problemas de salud. Las Regiones de Salud situadas en el Sur y Sudeste del país registraron menor cantidad y diversidad de barreras, revelando la persistencia de desigualdades regionales. A pesar de que los resultados no representen al conjunto del país, permiten apuntar cuestiones relevantes sobre el proceso de regionalización del sistema de salud en el país.
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Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Atenção Primária à Saúde/estatística & dados numéricos , Brasil , Pesquisa sobre Serviços de Saúde , Disparidades nos Níveis de Saúde , Humanos , Programas Nacionais de Saúde , Formulação de Políticas , Regionalização da Saúde , Características de Residência , Fatores Socioeconômicos , Inquéritos e QuestionáriosRESUMO
Integration of technological solutions aims to improve accuracy, precision and repeatability in farming operations, and biosensor devices are increasingly used for understanding basic biology during livestock production. The aim of this study was to design and validate a miniaturized tri-axial accelerometer for non-invasive monitoring of farmed fish with re-programmable schedule protocols. The current device (AE-FishBIT v.1s) is a small (14 mm × 7 mm × 7 mm), stand-alone system with a total mass of 600 mg, which allows monitoring animals from 30 to 35 g onwards. The device was attached to the operculum of gilthead sea bream (Sparus aurata) and European sea bass (Dicentrarchus labrax) juveniles for monitoring their physical activity by measurements of movement accelerations in x- and y-axes, while records of operculum beats (z-axis) served as a measurement of respiratory frequency. Data post-processing of exercised fish in swimming test chambers revealed an exponential increase of fish accelerations with the increase of fish speed from 1 body-length to 4 body-lengths per second, while a close relationship between oxygen consumption (MO2) and opercular frequency was consistently found. Preliminary tests in free-swimming fish kept in rearing tanks also showed that device data recording was able to detect changes in daily fish activity. The usefulness of low computational load for data pre-processing with on-board algorithms was verified from low to submaximal exercise, increasing this procedure the autonomy of the system up to 6 h of data recording with different programmable schedules. Visual observations regarding tissue damage, feeding behavior and circulating levels of stress markers (cortisol, glucose, and lactate) did not reveal at short term a negative impact of device tagging. Reduced plasma levels of triglycerides revealed a transient inhibition of feed intake in small fish (sea bream 50-90 g, sea bass 100-200 g), but this disturbance was not detected in larger fish. All this considered together is the proof of concept that miniaturized devices are suitable for non-invasive and reliable metabolic phenotyping of farmed fish to improve their overall performance and welfare. Further work is underway for improving the attachment procedure and the full device packaging.
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Sea urchin embryos have been used in toxicological studies for many decades as they are an accepted model system for investigations of chemicals that impact development. Here we describe methods for using pulse-chase experiments to study the impacts of environmental chemicals on early development as well as development of larvae. This includes the application of fluorescence plate assays with living embryos and fluorescent probes to assess cell functions (mitochondrial membrane potential, lysosome abundance, reactive oxygen species, and esterase activity) based on total cell numbers. We also describe how to use some of these fluorescent probes in embryos/larvae with confocal microscopy for the localization of cellular damage in response to toxics exposure. Finally, we assess skeleton formation in sea urchin larvae and present methods for using polarized light microscopy to examine spicule morphology.