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La amiloidosis es una enfermedad heterogénea, de origen hereditario o adquirido, que se caracteriza por el depósito anormal de proteínas fibrilares en diversos tejidos. Esta enfermedad puede manifestarse de manera localizada o sistémica, lo que genera una amplia variabilidad en su presentación clínica y, frecuentemente, retrasa el diagnóstico. Por ello, es fundamental la identificación temprana de los signos y síntomas para mejorar el pronóstico. El primer posicionamiento mexicano sobre la amiloidosis cardíaca tiene como objetivo resumir las principales características de la enfermedad y sus subtipos, identificando datos de alarma que incrementen la sospecha de su presencia. Además, busca ofrecer un algoritmo diagnóstico que integre los estudios de imagen y de laboratorio disponibles en nuestro país, con el fin de simplificar la toma de decisiones y llegar a un diagnóstico de manera rápida, práctica y actualizada, basado en recomendaciones sustentadas en evidencia científica. Una vez confirmado el diagnóstico, se abordan los distintos retos terapéuticos, tanto farmacológicos como no farmacológicos, ya que los pacientes no responden al tratamiento convencional de insuficiencia cardíaca. Por ello, el tratamiento debe ser individualizado para cada paciente, teniendo en cuenta la presencia de otras comorbilidades. Finalmente, se presentan los principales factores pronósticos que guiarán un tratamiento adecuado, incluyendo los resultados del asesoramiento genético.
Amyloidosis is a heterogeneous, hereditary or acquired disease characterized by the abnormal deposition of fibrillar proteins in various tissues. The disease can be either localized or systemic, leading to significant variability in its clinical presentation and often causing diagnostic delays. For this reason, early identification of signs and symptoms is essential to improve prognosis. The first Mexican position paper on cardiac amyloidosis aims to summarize the main features of the disease and its subtypes, identifying warning signs that increase clinical suspicion. Additionally, it provides a diagnostic algorithm incorporating the imaging and laboratory studies available in our country, to streamline decision-making and facilitate a fast, practical, and up-to-date diagnosis based on evidence-based recommendations. Once the diagnosis is confirmed, the various therapeutic challenges of this disease, both pharmacological and non-pharmacological, are discussed, as patients do not respond to conventional heart failure treatments. Therefore, treatment must be individualized for each patient, considering the presence of other comorbidities. Finally, the key prognostic factors are outlined to guide appropriate treatment, including results from genetic counseling.
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Amiloidose , Cardiomiopatias , Humanos , Amiloidose/diagnóstico , Amiloidose/terapia , México , Cardiomiopatias/diagnóstico , Cardiomiopatias/terapia , Prognóstico , AlgoritmosRESUMO
INTRODUCTION: The International Neuromodulation Society convened a multispecialty group of physicians based on expertise with international representation to establish evidence-based guidance on using intrathecal drug delivery in chronic pain treatment. This Polyanalgesic Consensus Conference (PACC)® project's scope is to provide evidence-based guidance for clinical pharmacology and best practices for intrathecal drug delivery for cancer pain. MATERIALS AND METHODS: Authors were chosen on the basis of their clinical expertise, familiarity with the peer-reviewed literature, research productivity, and contributions to the neuromodulation literature. Section leaders supervised literature searches using Medline, EMBASE, Cochrane CENTRAL, BioMed Central, Web of Science, Google Scholar, PubMed, Current Contents Connect, Meeting Abstracts, and Scopus from 2017 (when the PACC last published guidelines) to the present. Identified studies were graded using the United States Preventive Services Task Force criteria for evidence and certainty of net benefit. Recommendations were based on the strength of evidence, and when evidence was scant, recommendations were based on expert consensus. RESULTS: The PACC evaluated the published literature and established evidence- and consensus-based expert opinion recommendations to guide best practices in treating cancer pain. Additional guidance will occur as new evidence is developed in future iterations of this process. CONCLUSIONS: The PACC recommends best practices regarding the use of intrathecal drug delivery in cancer pain, with an emphasis on managing the unique disease and patient characteristics encountered in oncology. These evidence- and consensus-based expert opinion recommendations should be used as a guide to assist decision-making when clinically appropriate.
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Platelets are critical mediators of hemostasis and thrombosis. Platelets circulate as discs in their resting form but change shape rapidly upon activation by vascular damage and/or soluble agonists such as thrombin. Platelet shape change is driven by a dynamic remodeling of the actin cytoskeleton. Actin filaments interact with the protein myosin, which is phosphorylated on the myosin light chain (MLC) upon platelet activation. Actin-myosin interactions trigger contraction of the actin cytoskeleton, which drives platelet spreading and contractile force generation. Filamin A (FLNA) is an actin cross-linking protein that stabilizes the attachment between subcortical actin filaments and the cell membrane. In addition, FLNA binds multiple proteins and serves as a critical intracellular signaling scaffold. Here, we used platelets from mice with a megakaryocyte/platelet-specific deletion of FLNA to investigate the role of FLNA in regulating platelet shape change. Relative to controls, FLNA-null platelets exhibited defects in stress fiber formation, contractile force generation, and MLC phosphorylation in response to thrombin stimulation. Blockade of Rho kinase (ROCK) and protein kinase C (PKC) with the inhibitors Y27632 and bisindolylmaleimide (BIM), respectively, also attenuated MLC phosphorylation; our data further indicate that ROCK and PKC promote MLC phosphorylation through independent pathways. Notably, the activity of both ROCK and PKC was diminished in the FLNA-deficient platelets. We conclude that FLNA regulates thrombin-induced MLC phosphorylation and platelet contraction, in a ROCK- and PKC-dependent manner.
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Plaquetas , Filaminas , Cadeias Leves de Miosina , Filaminas/metabolismo , Animais , Cadeias Leves de Miosina/metabolismo , Plaquetas/metabolismo , Plaquetas/efeitos dos fármacos , Fosforilação , Camundongos , Quinases Associadas a rho/metabolismo , Proteína Quinase C/metabolismo , Trombina/farmacologia , Trombina/metabolismo , Camundongos Knockout , Forma Celular/efeitos dos fármacosRESUMO
Co-twin studies are an elegant and powerful design that allows controlling for the effect of confounding variables, including genetic and a range of environmental factors. There are several approaches to carry out this design. One of the methods commonly used, when contrasting continuous variables, is to calculate difference scores between members of a twin pair on two associated variables, in order to analyse the covariation of such differences. However, information regarding whether and how the different ways of estimating within-pair difference scores may impact the results is scant. This study aimed to compare the results obtained by different methods of data transformation when performing a co-twin study and test how the magnitude of the association changes using each of those approaches. Data was simulated using a direction of causation model and by fixing the effect size of causal path to low, medium, and high values. Within-pair difference scores were calculated as relative scores for diverse within-pair ordering conditions or absolute scores. Pearson's correlations using relative difference scores vary across the established scenarios (how twins were ordered within pairs) and these discrepancies become larger as the within-twin correlation increases. Absolute difference scores tended to produce the lowest correlation in every condition. Our results show that both using absolute difference scores or ordering twins within pairs, may produce an artificial decrease in the magnitude of the studied association, obscuring the ability to detect patterns compatible with causation, which could lead to discrepancies across studies and erroneous conclusions.
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Modelos Genéticos , Humanos , Gêmeos/genética , Gêmeos Monozigóticos/genética , Simulação por Computador , Projetos de Pesquisa , Gêmeos Dizigóticos/genética , Modelos Estatísticos , Estudos em Gêmeos como Assunto/métodosRESUMO
There is a critical need to increase Latino participation in research on Alzheimer's disease and related disorders (ADRD). Applying principles of community-based participatory research, we convened a community advisory board (CAB) to identify barriers and recommend strategies to increase participation of older Latinos in a longitudinal observational research study of ADRD at the Shiley-Marcos Alzheimer's Disease Research Center. Six major barriers were identified and programmatic changes to overcome them were implemented. Changes resulted in a nearly three-fold increase in the number of Latino individuals recruited, with the proportion of all newly recruited participants who were Latino increasing from 12.2% to 57.4%. Newer Latino recruits were more representative of the elderly Latino population in San Diego County than those recruited pre-CAB and remained highly agreeable to blood draw and neuroimaging, though less so to lumbar puncture and autopsy. Results demonstrate the value of CAB involvement in enhancing diversity in ADRD research.
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AIMS: Incomplete decongestion due to lack of titration of diuretics to effective doses is a common reason for readmission in patients with acute decompensated heart failure (ADHF). The natriuretic response prediction equation (NRPE) is a novel tool that proved to be rapid and accurate to predict natriuretic response and does not need urine collection. However, the NRPE has not been externally validated. The goal of this study was to externally validate the discrimination capacity of the NRPE in patients with ADHF and fluid overload. METHODS AND RESULTS: Patients admitted with ADHF who required intravenous loop diuretics were included. A spot urine sample was obtained ~2 h following diuretic administration, and a timed 6-h urine collection by study staff was carried out. Urine sodium and urine creatinine from the spot urine sample were used to predict the 6-h natriuretic response using the NRPE. The primary goal was to validate the NRPE to discriminate poor loop diuretic natriuretic response (sodium output <50 mmol in the 6 h following diuretic administration). The NRPE was compared with urine sodium and measured urine output which are the methods currently recommended by international guidelines to assess diuretic response. Eighty-seven diuretic administrations from 49 patients were analysed. Mean age of patients was 57 ± 17 years and 67% were male. Mean estimated glomerular filtration rate was 65 ± 28 mL/min/1.73 m2, and ejection fraction was 35 ± 15%. Median dose of intravenous furosemide equivalents administered the day of the study was 80 mg (IQR 40 - 160). Poor natriuretic response occurred in 39% of the visits. The AUC of the NRPE to predict poor natriuretic response during the 6-h urine collection was 0.91 (95% CI 0.85-0.98). Compared with the NRPE, spot urine sodium concentration (AUC 0.75) and urine output during the corresponding nursing shift (AUC 0.74) showed lower discrimination capacity. CONCLUSIONS: In this cohort of patients with ADHF, the NRPE outperformed spot urine sodium concentration and all other metrics related to diuretic response to predict poor natriuretic response. Our findings support the use of this equation at other settings to allow rapid and accurate prediction of natriuretic response.
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This paper proposes an advancement in the application of a Technical Vision System (TVS), which integrates a laser scanning mechanism with a single light sensor to measure 3D spatial coordinates. In this application, the system is used to scan and digitalize objects using a rotating table to explore the potential of the system for 3D scanning at reduced resolutions. The experiments undertaken searched for optimal scanning windows and used statistical data filtering techniques and regression models to find a method to generate a 3D scan that was still recognizable with the least amount of 3D points, balancing the number of points scanned and time, while at the same time reducing effects caused by the particularities of the TVS, such as noise and entropy in the form of natural distortion in the resulting scans. The evaluation of the experimentation results uses 3D point registration methods, joining multiple faces from the original volume scanned by the TVS and aligning it to the ground truth model point clouds, which are based on a commercial 3D camera to verify that the reconstructed 3D model retains substantial detail from the original object. This research finds it is possible to reconstruct sufficiently detailed 3D models obtained from the TVS, which contain coarsely scanned data or scans that initially lack high definition or are too noisy.
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Studies on adolescent rats, when body composition is changing deeply, reveal that the administration of sodium selenite and selenium nanoparticles (SeNPs), at the same dose, have opposite effects on adipogenesis in white adipose tissue (WAT). To investigate the mechanisms involved in these contrasting effects by means of transcriptomic analysis, three groups of male adolescent rats (n = 18) were used: control (C), selenite supplemented (S), and SeNPs supplemented (NS). Both treated groups received a twofold increase in Se dose compared to the control group through water intake for three weeks. Following treatment, WAT was removed and frozen at -80 °C until subsequent use for RNA extraction, endogenous antioxidant enzymatic activities determination, and quantification of H2O2 and malondialdehyde. NS rats displayed a larger number of differentially expressed genes and cellular processes impacted than S rats. Remarkably, these changes involved upregulation of gene expression associated with the immune system, catabolism, mitochondrial function, and oxidative balance. NS rats presented an increase in antioxidant enzymes activity, alongside an accumulation of H2O2 and malondialdehyde levels. The expression level of 81 genes related to oxidative stress was significantly affected in NS rats. Analyzing the KEGG pathway enrichment revealed that NS rats exhibited increased activity in key catabolic pathways and decreased activity in crucial growth signaling processes. These changes contribute to the mass decrease in WAT found in NS rats. These results suggest a possible application of SeNPs in WAT reduction and induction of the immune response during adolescence.
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The exchange of genes between cells is known to play an important physiological and pathological role in many organisms. We show that circulating tumor DNA (ctDNA) facilitates cell-specific gene transfer between human cancer cells and explain part of the mechanisms behind this phenomenon. As ctDNA migrates into the nucleus, genetic information is transferred. Cell targeting and ctDNA integration require ERVL, SINE or LINE DNA sequences. Chemically manufactured AluSp and MER11C sequences replicated multiple myeloma (MM) ctDNA cell targeting and integration. Additionally, we found that ctDNA may alter the treatment response of MM and pancreatic cancer models. This study shows that retrotransposon DNA sequences promote cancer gene transfer. However, because cell-free DNA has been detected in physiological and other pathological conditions, our findings have a broader impact than just cancer. Furthermore, the discovery that transposon DNA sequences mediate tissue-specific targeting will open up a new avenue for the delivery of genes and therapies.
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DNA Tumoral Circulante , Elementos de DNA Transponíveis , Humanos , DNA Tumoral Circulante/genética , DNA Tumoral Circulante/sangue , Elementos de DNA Transponíveis/genética , Linhagem Celular Tumoral , Mieloma Múltiplo/genética , Mieloma Múltiplo/terapia , Animais , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/terapia , Camundongos , Especificidade de Órgãos/genética , Retroelementos/genética , Técnicas de Transferência de GenesRESUMO
BACKGROUND: Thromboinflammation involving platelet adhesion to endothelial surface-associated von Willebrand factor (VWF) has been implicated in the accelerated progression of non-culprit plaques after MI. The aim of this study was to use arterial endothelial molecular imaging to mechanistically evaluate endothelial-associated VWF as a therapeutic target for reducing remote plaque activation after myocardial infarction (MI). METHODS: Hyperlipidemic mice deficient for the low-density lipoprotein receptor and Apobec-1 underwent closed-chest MI and were treated chronically with either: (i) recombinant ADAMTS13 which is responsible for proteolytic removal of VWF from the endothelial surface, (ii) N-acetylcysteine (NAC) which removes VWF by disulfide bond reduction, (iii) function-blocking anti-factor XI (FXI) antibody, or (iv) no therapy. Non-ischemic controls were also studied. At day 3 and 21, ultrasound molecular imaging was performed with probes targeted to endothelial-associated VWF A1-domain, platelet GPIbα, P-selectin and vascular cell adhesion molecule-1 (VCAM-1) at lesion-prone sites of the aorta. Histology was performed at day 21. RESULTS: Aortic signal for P-selectin, VCAM-1, VWF, and platelet-GPIbα were all increased several-fold (p < 0.01) in post-MI mice versus sham-treated animals at day 3 and 21. Treatment with NAC and ADAMTS13 significantly attenuated the post-MI increase for all four molecular targets by > 50% (p < 0.05 vs. non-treated at day 3 and 21). On aortic root histology, mice undergoing MI versus controls had 2-4 fold greater plaque size and macrophage content (p < 0.05), approximately 20-fold greater platelet adhesion (p < 0.05), and increased staining for markers of platelet transforming growth factor-ß1 signaling. Accelerated plaque growth and inflammatory activation was almost entirely prevented by ADAMTS13 and NAC. Inhibition of FXI had no significant effect on molecular imaging signal or plaque morphology. CONCLUSIONS: Plaque inflammatory activation in remote arteries after MI is strongly influenced by VWF-mediated platelet adhesion to the endothelium. These findings support investigation into new secondary preventive therapies for reducing non-culprit artery events after MI.
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Proteína ADAMTS13 , Infarto do Miocárdio , Fator de von Willebrand , Animais , Fator de von Willebrand/metabolismo , Infarto do Miocárdio/patologia , Infarto do Miocárdio/complicações , Proteína ADAMTS13/metabolismo , Molécula 1 de Adesão de Célula Vascular/metabolismo , Camundongos , Placa Aterosclerótica/patologia , Selectina-P/metabolismo , Células Endoteliais/metabolismo , Células Endoteliais/efeitos dos fármacos , Masculino , Imagem Molecular , Aorta/patologia , Aorta/efeitos dos fármacos , Acetilcisteína/farmacologia , Acetilcisteína/uso terapêutico , Camundongos Endogâmicos C57BLRESUMO
BACKGROUND: Depression is a common mental health disorder that often starts during adolescence, with potentially important future consequences including 'Not in Education, Employment or Training' (NEET) status. METHODS: We took a structured life course modeling approach to examine how depressive symptoms during adolescence might be associated with later NEET status, using a high-quality longitudinal data resource. We considered four plausible life course models: (1) an early adolescent sensitive period model where depressive symptoms in early adolescence are more associated with later NEET status relative to exposure at other stages; (2) a mid adolescent sensitive period model where depressive symptoms during the transition from compulsory education to adult life might be more deleterious regarding NEET status; (3) a late adolescent sensitive period model, meaning that depressive symptoms around the time when most adults have completed their education and started their careers are the most strongly associated with NEET status; and (4) an accumulation of risk model which highlights the importance of chronicity of symptoms. RESULTS: Our analysis sample included participants with full information on NEET status (N = 3951), and the results supported the accumulation of risk model, showing that the odds of NEET increase by 1.015 (95% CI 1.012-1.019) for an increase of 1 unit in depression at any age between 11 and 24 years. CONCLUSIONS: Given the adverse implications of NEET status, our results emphasize the importance of supporting mental health during adolescence and early adulthood, as well as considering specific needs of young people with re-occurring depressed mood.
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Chronic heart failure continues to be one of the main causes of impairment in the functioning and quality of life of people who suffer from it, as well as one of the main causes of mortality in our country and around the world. Mexico has a high prevalence of risk factors for developing heart failure, such as high blood pressure, diabetes, and obesity, which makes it essential to have an evidence-based document that provides recommendations to health professionals involved in the diagnosis and treatment of these patients. This document establishes the clinical practice guide (CPG) prepared at the initiative of the Mexican Society of Cardiology (SMC) in collaboration with the Iberic American Agency for the Development and Evaluation of Health Technologies, with the purpose of establishing recommendations based on the best available evidence and agreed upon by an interdisciplinary group of experts. This document complies with international quality standards, such as those described by the US Institute of Medicine (IOM), the National Institute of Clinical Excellence (NICE), the Intercollegiate Network for Scottish Guideline Development (SIGN) and the Guidelines International Network (G-I-N). The Guideline Development Group was integrated in a multi-collaborative and interdisciplinary manner with the support of methodologists with experience in systematic literature reviews and the development of CPG. A modified Delphi panel methodology was developed and conducted to achieve an adequate level of consensus in each of the recommendations contained in this CPG. We hope that this document contributes to better clinical decision making and becomes a reference point for clinicians who manage patients with chronic heart failure in all their clinical stages and in this way, we improve the quality of clinical care, improve their quality of life and reducing its complications.
La insuficiencia cardiaca crónica sigue siendo unas de las principales causas de afectación en el funcionamiento y en la calidad de vida de las personas que la presentan, así como una de las primeras causas de mortalidad en nuestro país y en todo el mundo. México tiene una alta prevalencia de factores de riesgo para desarrollar insuficiencia cardiaca, tales como hipertensión arterial, diabetes y obesidad, lo que hace imprescindible contar con un documento basado en la evidencia que brinde recomendaciones a los profesionales de la salud involucrados en el diagnóstico y el tratamiento de estos pacientes. Este documento establece la guía de práctica clínica (GPC) elaborada por iniciativa de la Sociedad Mexicana de Cardiología (SMC) en colaboración con la Agencia Iberoamericana de Desarrollo y Evaluación de Tecnologías en Salud, con la finalidad de establecer recomendaciones basadas en la mejor evidencia disponible y consensuadas por un grupo interdisciplinario y multicolaborativo de expertos. Cumple con estándares internacionales de calidad, como los descritos por el Institute of Medicine de los Estados Unidos de América (IOM), el National Institute of Clinical Excellence (NICE) del Reino Unido, la Intercollegiate Network for Scottish Guideline Development (SIGN) de Escocia y la Guidelines International Network (G-I-N). El grupo de desarrollo de la guía se integró de manera interdisciplinaria con el apoyo de metodólogos con experiencia en revisiones sistemáticas de la literatura y en el desarrollo de GPC. Se llevó a cabo y se condujo metodología de panel Delphi modificado para lograr un nivel de consenso adecuado en cada una de las recomendaciones contenidas en esta GPC. Esperamos que este documento contribuya para la mejor toma de decisiones clínicas y se convierta en un punto de referencia para los clínicos que manejan pacientes con insuficiencia cardiaca crónica en todas sus etapas clínicas, y de esta manera logremos mejorar la calidad en la atención clínica, aumentar la calidad de vida de los pacientes y disminuir las complicaciones de la enfermedad.
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Insuficiência Cardíaca , Humanos , Insuficiência Cardíaca/terapia , Insuficiência Cardíaca/diagnóstico , Doença Crônica , MéxicoRESUMO
The detection of temperature by the human sensory system is life-preserving and highly evolutionarily conserved. Platelets are sensitive to temperature changes and are activated by a decrease in temperature, akin to sensory neurons. However, the molecular mechanism of this temperature-sensing ability is unknown. Yet, platelet activation by temperature could contribute to numerous clinical sequelae, most importantly to reduced quality of ex vivo-stored platelets for transfusion. In this multidisciplinary study, we present evidence for the expression of the temperature-sensitive ion channel transient receptor potential cation channel subfamily member 8 (TRPM8) in human platelets and precursor cells. We found the TRPM8 mRNA and protein in MEG-01 cells and platelets. Inhibition of TRPM8 prevented temperature-induced platelet activation and shape change. However, chemical agonists of TRPM8 did not seem to have an acute effect on platelets. When exposing platelets to below-normal body temperature, we detected a cytosolic calcium increase which was independent of TRPM8 but was completely dependent on the calcium release from the endoplasmic reticulum. Because of the high interindividual variability of TRPM8 expression, a population-based approach should be the focus of future studies. Our study suggests that the cold response of platelets is complex and TRPM8 appears to play a role in early temperature-induced activation of platelets, while other mechanisms likely contribute to later stages of temperature-mediated platelet response.
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Cálcio , Canais de Cátion TRPM , Humanos , Temperatura Baixa , Cálcio da Dieta , Retículo Endoplasmático , Células Receptoras Sensoriais , Canais de Cátion TRPM/genética , Proteínas de MembranaRESUMO
Bioaccumulation patterns of heavy metals (Pb, Cd, Cr, Ni, Fe and Cu) and organic (priority and emerging) pollutants, in combination with stable isotope analysis (SIA), were assessed in muscle and liver of three tuna species from the Gulf of Cadiz (Atlantic bluefin tuna, Thunnus thynnus; Atlantic bonito, Sarda sarda, and skipjack tuna, Katsuwonus pelamis). SIA and contaminant (heavy metal and organic) profiles separately discriminated between species. There was no significant overlap between the trophic niches estimated from isotopic data, suggesting that there are diet differences which may determine differential bioaccumulation patterns. The levels of heavy metals and persistent organic pollutants in muscle of all the individuals analyzed were below the allowable limits established by the current legislation. Concentrations of most contaminants were higher in liver than in muscle, underlining the powerful detoxifying capacity of the liver in tunas. In addition to diet, other factors such as size and age (exposure time to environmental chemicals) explain differences in pollutant accumulation patterns in tissues between species, each with varying degrees of involvement depending on the pollutant class. Our results show that combining contaminant profile data with trophic features based on SIA may help understand pollutant bioaccumulation patterns in upper levels of marine food webs.
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Poluentes Ambientais , Metais Pesados , Humanos , Animais , Atum , Metais Pesados/análise , Isótopos/análise , Cadeia AlimentarRESUMO
Cell Competition is a process by which neighboring cells compare their fitness. As a result, viable but suboptimal cells are selectively eliminated in the presence of fitter cells. In the early mammalian embryo, epiblast pluripotent cells undergo extensive Cell Competition, which prevents suboptimal cells from contributing to the newly forming organism. While competitive ability is regulated by MYC in the epiblast, the mechanisms that contribute to competitive fitness in this context are largely unknown. Here, we report that P53 and its pro-apoptotic targets PUMA and NOXA regulate apoptosis susceptibility and competitive fitness in pluripotent cells. PUMA is widely expressed specifically in pluripotent cells in vitro and in vivo. We found that P53 regulates MYC levels in pluripotent cells, which connects these two Cell Competition pathways, however, MYC and PUMA/NOXA levels are independently regulated by P53. We propose a model that integrates a bifurcated P53 pathway regulating both MYC and PUMA/NOXA levels and determines competitive fitness.
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Competição entre as Células , Proteínas Proto-Oncogênicas c-bcl-2 , Proteína Supressora de Tumor p53 , Animais , Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Competição entre as Células/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proteínas Supressoras de Tumor/metabolismo , CamundongosRESUMO
Protein S (PS), the critical plasma cofactor for the anticoagulants tissue factor (TF) pathway inhibitor (TFPI) and activated protein C (APC), circulates in two functionally distinct pools: free (anticoagulant) or bound to complement component 4b-binding protein (C4BP) (anti-inflammatory). Acquired free PS deficiency is detected in several viral infections, but its cause is unclear. Here, we identified a shear-dependent interaction between PS and von Willebrand Factor (VWF) by mass spectrometry. Consistently, plasma PS and VWF comigrated in both native and agarose gel electrophoresis. The PS/VWF interaction was blocked by TFPI but not APC, suggesting an interaction with the C-terminal sex hormone binding globulin (SHBG) region of PS. Microfluidic systems, mimicking arterial laminar flow or disrupted turbulent flow, demonstrated that PS stably binds VWF as VWF unfolds under turbulent flow. PS/VWF complexes also localized to platelet thrombi under laminar arterial flow. In thrombin generation-based assays, shearing plasma decreased PS activity, an effect not seen in the absence of VWF. Finally, free PS deficiency in COVID-19 patients, measured using an antibody that binds near the C4BP binding site in SHBG, correlated with changes in VWF, but not C4BP, and with thrombin generation. Our data suggest that PS binds to a shear-exposed site on VWF, thus sequestering free PS and decreasing its anticoagulant activity, which would account for the increased thrombin generation potential. As many viral infections present with free PS deficiency, elevated circulating VWF, and increased vascular shear, we propose that the PS/VWF interaction reported here is a likely contributor to virus-associated thrombotic risk.
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Neuroendocrine tumors comprise a range of neoplasms with varying spectra of origin, biological activity, clinical features, and histological appearance. In this case report, we present a pregnant 33-year-old female who was brought to the emergency department (ED) complaining of acute right iliac fossa pain accompanied by diarrhea and vomiting. Initial management showed no improvement. Lab results, clinical history, and physical exam were suggestive of appendicitis, so an exploratory minimally invasive laparoscopic exam was performed. The histopathological analysis of the excised appendix confirmed the diagnosis of acute appendicitis and periappendicitis. Incidentally, a 0.6 cm neuroendocrine tumor (carcinoid tumor) was identified on the wall of the appendiceal tip. The tumor extended at multiple points into the subserosal fat, and the serous surface and the resection margin were negative for the tumor. After seven days of the initial procedure, the patient presented with abdominal pain and a fever. An abdominal ultrasound was performed, revealing the presence of free fluid. A second exploratory laparoscopy revealed adhesions between the fallopian tubes and cecum, as well as a collection of purulent fluid. The management consisted of adhesiolysis, cavity lavage, and drainage, along with antibiotic therapy, pain management, and close monitoring of the mother's and fetus's status. The patient had a successful recovery and was discharged home a week after surgery. She gave birth to a full-term, healthy baby and remains free of tumor relapse. This case highlights the importance of obtaining histopathological interpretation of any extracted tissue during surgery. Guidelines regarding the management of carcinoids during pregnancy are not available, and when considering surgical intervention, an open or laparoscopic approach must be carefully evaluated.