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In the published publication [...].
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Mass spectrometry-based proteomics has traditionally been limited by the amount of input material for analysis. Single-cell proteomics has emerged as a challenging discipline due to the ultra-high sensitivity required. Isobaric labeling-based multiplex strategies with a carrier proteome offer an approach to overcome the sensitivity limitations. Following this as the basic strategy, we show here the general workflow for preparing cells for single-cell mass spectrometry-based proteomics. This protocol can also be applied to manually isolated cells when large cells, such as cardiomyocytes, are difficult to isolate properly with conventional fluorescence-activated cell sorting (FACS) sorter methods.
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Proteômica , Análise de Célula Única , Proteômica/métodos , Análise de Célula Única/métodos , Humanos , Espectrometria de Massas/métodos , Citometria de Fluxo/métodos , Proteoma/análise , Animais , Marcação por Isótopo/métodos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/citologia , Coloração e Rotulagem/métodosRESUMO
Background: Hematological neoplasms (HNs) are the first and most common childhood cancers globally. Currently, there is a lack of updated population-based data on the incidence of these cancers in the Spanish pediatric population. This study aimed to describe the incidence and incidence trends of HNs in children (0-14 years) in Spain using data from the Spanish Network of Cancer Registries and to compare the results with other southern European countries. Methods: Data were extracted from 15 Spanish population-based cancer registries between 1983 and 2018. Cases were coded according to the International Classification of Diseases for Oncology, third edition, first revision, and grouped according to the International Classification of Childhood Cancer, third edition. Crude rates (CRs), age-specific rates, and age-standardized incidence rates using the 2013 European population (ASRE) were calculated and expressed as cases per 1,000,000 child-years. Incidence trends and annual percentage changes (APCs) were estimated. Results: A total of 4,747 HNs were recorded (59.5% boys). Age distribution [n (%)] was as follows: <1 year, 266 (5.6%); 1-4 years, 1,726 (36.4%); 5-9 years, 1,442 (30.4%); and 10-14 years, 1,313 (27.6%). Leukemias were the most common group, with a CR and an ASRE of 44.0 (95%CI: 42.5; 45.5) and 44.1 (95%CI: 42.6; 45.7), respectively. The CR and ASRE of lymphomas were 20.1 (95%CI: 19.1; 21.1) and 20.0 (95%CI: 19.0; 21.1), respectively. The comparable incidence rates between our results and those of other southern European countries were similar for lymphomas, while some differences were observed for leukemias. From 1988 to 2016, the trend in leukemia incidence was stable for both sexes, with an APC of 0.0 (95%CI: -0.5; 0.7), whereas a constant overall increase was observed for lymphoma in both sexes, with an APC of 1.0 (95%CI: 0.4; 1.6). Conclusion: Leukemias are the most common HNs in children, and their incidence has remained stable since 1988, whereas the incidence of lymphomas has increased every year. Lymphoma incidence is like that of other southern European countries, while leukemia incidence is similar only to that of southwestern European countries. Collaborative cancer registry projects allow for assessing epidemiological indicators for cancers such as HNs, which helps health authorities and clinicians provide more knowledge about these malignancies.
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The Wilms tumor suppressor gene (Wt1) encodes a C2H2-type zinc-finger transcription factor that participates in transcriptional regulation, RNA metabolism, and protein-protein interactions. WT1 is involved in the development of several organs, including the kidneys and gonads, heart, spleen, adrenal glands, liver, diaphragm, and neuronal system. We previously provided evidence of transient WT1 expression in about 25% of cardiomyocytes of mouse embryos. Conditional deletion of Wt1 in the cardiac troponin T lineage caused abnormal cardiac development. A low expression of WT1 has also been reported in adult cardiomyocytes. Therefore, we aimed to explore its function in cardiac homeostasis and in the response to pharmacologically induced damage. Silencing of Wt1 in cultured neonatal murine cardiomyocytes provoked alterations in mitochondrial membrane potential and changes in the expression of genes related to calcium homeostasis. Ablation of WT1 in adult cardiomyocytes by crossing αMHCMerCreMer mice with homozygous WT1-floxed mice induced hypertrophy, interstitial fibrosis, altered metabolism, and mitochondrial dysfunction. In addition, conditional deletion of WT1 in adult cardiomyocytes increased doxorubicin-induced damage. These findings suggest a novel role of WT1 in myocardial physiology and protection against damage.
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Business degrees have been pioneers in adopting the internationalization of Higher Education Institutions with the option of English as Medium of Instruction (EMI). Research has grown about the EMI versus non-EMI lecturers and students' performance measured through perception, motivation, discursive analysis or satisfaction measures. However, results have not been conclusive in the scarce number of papers comparing quantitative course grades of EMI versus non-EMI students. The aim of this research paper is to prove that there is no difference in attaining learning objectives among students within a Business Administration Degree in Spain regardless the language of instruction. The present observational study considers all enrolled freshman throughout a horizon of six consecutive years allowing more reliable results not affected by the specificities of courses or years. All 212 students in the EMI track were matched to non-EMI track counterparts taking into account all available covariates. Results not only show that there is no difference in the attained learning objectives between the two tracks, but also that EMI students' grades are in fact better than their non-EMI counterparts, which might help to remove the believe many still have on the lower academic attainment of those following an EMI track.
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Instituições Acadêmicas , Estudantes , Humanos , Avaliação de Programas e Projetos de Saúde , Idioma , AprendizagemRESUMO
Introduction: The aim of this study was to describe incidence, incidence trends and survival patterns of lymphoid neoplasms (LNs) and its subtypes in Spain in the period 2002-2013 using data from the Spanish Network of Cancer Registries (REDECAN). Materials and Methods: Data were extracted from 13 Spanish population-based cancer registries. LNs incident cases were codified using the International Classification of Diseases for Oncology, third edition (ICD-O-3) and grouped according to the WHO 2008 classification. Age-standardized incidence rates to the 2013 European standard population (ASIRe) were obtained. Poisson regression models were used to analyze trends in incidence rates and estimate the annual percentage change (APC) for each subtype. The number of cases in Spain for 2023 was estimated by applying the estimated age-specific rates for the year 2023 to the 2023 Spanish population. Observed survival (OS) was estimated by the Kaplan-Meier method and net survival (NS) by the Pohar-Perme method. Sex- and age-specific estimates of 5-year NS were calculated, as well as its changes according to two periods of diagnosis (2002-2007 and 2008-2013). Results: LNs accounted for 69% (n=39,156) of all hematological malignancies (n=56,751) diagnosed during the period of study. Median age at diagnosis was 67 years (interquartile range (IQR) = 52-77). The overall ASIRe was 34.23 (95% confidence interval (CI): 33.89, 34.57) and showed a marked male predominance in almost all subtypes (global sex ratio = 1.45). During the study period, incidence trends of LNs remained stable (APC: 0.3; 95% CI: -0.1, 0.6), nevertheless some subtypes showed statistically significant variations, such as LNs NOS category (APC: -5.6; 95% CI: -6.8, -4.3). Around 17,926 new cases of LNs will be diagnosed in 2023 in Spain. Survival rates differed considerably across age-groups, while they were similar between men and women. Five- year NS was 62.81% (95% CI: 62.1, 63.52) for all LNs, and varied widely across LNs subtypes, ranging from 39.21% to 90.25%. NS for all LNs improved from the first period of diagnosis to the second one, being 61.57% (95% CI: 60.56, 62.61) in 2002-2007 and 64.17% (95% CI: 63.29, 65.07) in 2008-2013. Conclusions: This study presents the first complete and extensive population-based analysis of LNs incidence and survival in Spain. These population-based data provide relevant information to better understand the epidemiology of LNs in Southern Europe and it features some useful points for public health authorities and clinicians. However, additional improvements regarding the registration of these hematological neoplasms can be implemented.
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In recent years, studies have been conducted to quantify the relationship between microeconomic and macroeconomic development. Macroeconomics is the orientation of microeconomic development. Existing research hopes to quantify the relationship between macroeconomics and micro-firms, rather than just focusing on economic indicators. And some empirical studies try to use the relationship between them to discuss its usefulness for micro-firm decision-making. This article focuses on applying and developing aggregate earnings in connecting microenterprise earnings and macroeconomic development. To achieve this goal, this research did a comprehensive bibliometric analysis on macro-accounting on the two most influential databases, namely, Web of Science and Scopus. It used the information visualization software VOSviewer to draw knowledge maps to sort research lines. We also analyzed the research hotspots of macro-accounting in recent years according to the year scale and combined it with the neural network PSO-LSTM model to predict their future development. It turns out that the research on aggregate earnings related to economic growth has become a research hotspot in recent years. Scopus research and development potential is better than Web of Science in this field.
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Bibliometria , Desenvolvimento Econômico , Bases de Dados Factuais , Conhecimento , SoftwareRESUMO
Financial inclusion has been broadly recognized as critical in alleviating poverty and achieving inclusive economic growth. The capability of borrowers to repay their microcredit loans is a critical concern and is the first risk of Microfinance institutions sustainability. Exploring the determinants of credit risk is an issue of substantial importance in microfinance. The purpose of this research was to identify the savings group members' characteristics that have impact on default risk. We have used a multivariate regression model to identify the factors that affect default behaviour among microcredit borrowers from savings groups. We have analysed a sample of more than different 400 Savings Groups and 7251 active users of the "Saving and Learning" program in Ecuador. Empirical results demonstrated that factors such as seniority, accumulated savings and the number of members in the savings groups are determinant variables of default risk. The significant positive sign on variable "Gender" is consistent with the previous authors that indicate that the probability of having problems in loan repayment is higher for males than for females. The generalizability of our findings should, of course, be interpreted with caution, as they may be idiosyncratic of the sample, period or region. To contrast and contextualize these results, we had in-depth discussions with the Savinco managers and their field agent in Ecuador. There are many contributions. For practitioners, relevant factors that can affect savings groups default rates have been identified. For academics, the rich information provided by the Savinco mobile App could be a starting point for further quantitative research.
Il est largement reconnu que l'inclusion financière est essentielle pour réduire la pauvreté et parvenir à une croissance économique inclusive. La capacité des emprunteurs à rembourser leurs prêts de microcrédit est une préoccupation essentielle et constitue le premier risque pour la pérennité des institutions de microfinance. L'étude des déterminants du risque de crédit est une question d'une importance capitale en microfinance. Le but de cette étude est d'identifier les caractéristiques des membres de groupes d'épargne qui ont un impact sur le risque de défaut de paiement. Nous avons utilisé un modèle de régression multivariée pour identifier les facteurs qui affectent le comportement de défaut de paiement parmi les emprunteurs de microcrédit au sein de groupes d'épargne. Nous avons analysé un échantillon de plus de 400 groupes d'épargne différents et 7 251 utilisateurs actifs du programme « Épargne et apprentissage ¼ en Équateur. Les résultats empiriques ont démontré que des facteurs tels que l'ancienneté, l'épargne accumulée et le nombre de membres dans les groupes d'épargne sont des variables déterminantes du risque de défaut de paiement. Sur la variable « Genre ¼, le signe positif significatif est cohérent avec les études précédentes qui indiquent que la probabilité d'avoir des problèmes de remboursement de prêt est plus élevée chez les hommes que chez les femmes. Bien entendu, le caractère généralisable de nos résultats doit être interprété avec prudence, car ces résultats peuvent être uniques à l'échantillon, à la période ou à la région. Pour contraster et contextualiser ces résultats, nous avons eu des discussions approfondies avec les gestionnaires de Savinco et leur agent de terrain en Équateur. Les contributions sont nombreuses. Pour les praticiens, ont été identifiés les facteurs pertinents pouvant affecter le taux de défaut de paiement des groupes d'épargne. Pour les universitaires, les riches informations fournies par l'application mobile Savinco pourraient être un point de départ pour d'autres études quantitatives.
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AIMS: After a myocardial infarction, the adult human heart lacks sufficient regenerative capacity to restore lost tissue, leading to heart failure progression. Finding novel ways to reprogram adult cardiomyocytes into a regenerative state is a major therapeutic goal. The epicardium, the outermost layer of the heart, contributes cardiovascular cell types to the forming heart and is a source of trophic signals to promote heart muscle growth during embryonic development. The epicardium is also essential for heart regeneration in zebrafish and neonatal mice and can be reactivated after injury in adult hearts to improve outcome. A recently identified mechanism of cell-cell communication and signalling is that mediated by extracellular vesicles (EVs). Here, we aimed to investigate epicardial signalling via EV release in response to cardiac injury and as a means to optimize cardiac repair and regeneration. METHODS AND RESULTS: We isolated epicardial EVs from mouse and human sources and targeted the cardiomyocyte population. Epicardial EVs enhanced proliferation in H9C2 cells and in primary neonatal murine cardiomyocytes in vitro and promoted cell cycle re-entry when injected into the injured area of infarcted neonatal hearts. These EVs also enhanced regeneration in cryoinjured engineered human myocardium (EHM) as a novel model of human myocardial injury. Deep RNA-sequencing of epicardial EV cargo revealed conserved microRNAs (miRs) between human and mouse epicardial-derived exosomes, and the effects on cell cycle re-entry were recapitulated by administration of cargo miR-30a, miR-100, miR-27a, and miR-30e to human stem cell-derived cardiomyocytes and cryoinjured EHM constructs. CONCLUSION: Here, we describe the first characterization of epicardial EV secretion, which can signal to promote proliferation of cardiomyocytes in infarcted mouse hearts and in a human model of myocardial injury, resulting in enhanced contractile function. Analysis of exosome cargo in mouse and human identified conserved pro-regenerative miRs, which in combination recapitulated the therapeutic effects of promoting cardiomyocyte proliferation.
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Proliferação de Células , Vesículas Extracelulares/transplante , MicroRNAs/metabolismo , Infarto do Miocárdio/cirurgia , Miócitos Cardíacos/metabolismo , Pericárdio/transplante , Regeneração , Animais , Animais Recém-Nascidos , Linhagem Celular , Modelos Animais de Doenças , Vesículas Extracelulares/metabolismo , Células-Tronco Embrionárias Humanas/metabolismo , Humanos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Contração Miocárdica , Infarto do Miocárdio/genética , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/fisiopatologia , Miócitos Cardíacos/patologia , Comunicação Parácrina , Pericárdio/metabolismo , Ratos , Recuperação de Função Fisiológica , Fatores de TempoRESUMO
OBJECTIVE: To analyze whether the drug safety update issued by the Spanish Agency of Medicines and Healthcare Products (AEMPS), dated October 30, 2018, on agranulocytosis and metamizole contains accurate and necessary information to protect patients from the presentation of this adverse reaction (AR) and if the official documentation of medicines containing metamizole for doctors, pharmacists and the general population conforms to the guidelines of the AEMPS to reduce this risk. SETTING AND PARTICIPANTS: Drug safety update, bibliographic search, information at the European Medicines Agency on metamizole drugs marketed in Spain, technical datasheets, leaflets, Bot PLUS Health Information Database and Catalog of Pharmaceutical Specialties. Notification of 4cases of agranulocytosis due to metamizole after the drug safety update was issued. MAIN INTERVENTIONS AND MEASUREMENTS: Comparison of the key points of the drug safety update and official documents on metamizole with the bibliography. Description of the 4cases of agranulocytosis due to metamizole and application of the causality and severity algorithm. RESULTS: The drug safety update contains omissions and contradiction in respect to the bibliography and the actual use of metamizole in healthcare practice. The official documents show a lack of updating, unapproved indications and doses higher than those recommended. The drug safety update has not stopped the presentation of cases of agranulocytosis due to metamizole. CONCLUSIONS: The AEMPS drug safety update can be improved and it is necessary to update the official information documents on metamizole for health professionals and patients in order to decrease the risk of agranulocytosis.
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Agranulocitose , Dipirona , Agranulocitose/induzido quimicamente , Anti-Inflamatórios não Esteroides/efeitos adversos , Bases de Dados Factuais , Dipirona/efeitos adversos , Humanos , EspanhaRESUMO
The Spanish Society for Developmental Biology (SEBD) organized its 17th meeting in November 2020 (herein referred to as SEBD2020). This meeting, originally programmed to take place in the city of Bilbao, was forced onto an online format due to the SARS-CoV2, COVID-19 pandemic. Although, we missed the live personal interactions and missed out on the Bilbao social scene, we were able to meet online to present our work and discuss our latest results. An overview of the activities that took place around the meeting, the different scientific sessions and the speakers involved are presented here. The pros and cons of virtual meetings are discussed.
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Biologia do Desenvolvimento/métodos , Biologia do Desenvolvimento/tendências , Animais , Biologia Celular/tendências , Biologia do Desenvolvimento/educação , Humanos , Internet , Modelos Animais , Sistema Nervoso , Revisão por Pares , Publicações , Editoração , Regeneração , Instituições Acadêmicas , Sociedades Médicas , EspanhaRESUMO
Macrophages are components of the innate immune system with key roles in tissue inflammation and repair. It is now evident that macrophages also support organogenesis, but few studies have characterized their identity, ontogeny and function during heart development. Here, we show that the distribution and prevalence of resident macrophages in the subepicardial compartment of the developing heart coincides with the emergence of new lymphatics, and that macrophages interact closely with the nascent lymphatic capillaries. Consequently, global macrophage deficiency led to extensive vessel disruption, with mutant hearts exhibiting shortened and mis-patterned lymphatics. The origin of cardiac macrophages was linked to the yolk sac and foetal liver. Moreover, the Cx3cr1+ myeloid lineage was found to play essential functions in the remodelling of the lymphatic endothelium. Mechanistically, macrophage hyaluronan was required for lymphatic sprouting by mediating direct macrophage-lymphatic endothelial cell interactions. Together, these findings reveal insight into the role of macrophages as indispensable mediators of lymphatic growth during the development of the mammalian cardiac vasculature.
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Coração/crescimento & desenvolvimento , Vasos Linfáticos , Macrófagos/metabolismo , Animais , Receptor 1 de Quimiocina CX3C/genética , Adesão Celular , Linhagem Celular , Células Endoteliais , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Introdução de Genes , Humanos , Inflamação , Linfangiogênese , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Organogênese/genética , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos/genética , Saco VitelinoRESUMO
As we age, our tissues become a mosaic of random mutations, many of which are oncogenic and promote the expansion of their carrier cells. In this issue of Cell Stem Cell, Fernandez-Antoran et al. (2019) show how commonly used medical procedures modify cell selection dynamics to either expand or eliminate cells carrying oncogenic p53 mutations.
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Oncogenes , Proteína Supressora de Tumor p53 , Esôfago , Mutação , OxirreduçãoRESUMO
Myc is considered an essential transcription factor for heart development, but cardiac defects have only been studied in global Myc loss-of-function models. Here, we eliminated Myc by recombining a Myc floxed allele with the Nkx2.5Cre driver. We observed no anatomical, cellular or functional alterations in either fetuses or adult cardiac Myc-deficient mice. We re-examined Myc expression during development and found no expression in developing cardiomyocytes. In contrast, we confirmed that Mycn is essential for cardiomyocyte proliferation and cardiogenesis. Mosaic Myc overexpression in a Mycn-deficient background shows that Myc can replace Mycn function, recovering heart development. We further show that this recovery involves the elimination of Mycn-deficient cells by cell competition. Our results indicate that Myc is dispensable in cardiomyocytes both during cardiogenesis and for adult heart homeostasis, and that Mycn is exclusively responsible for cardiomyocyte proliferation during heart development. Nonetheless, our results show that Myc can functionally replace Mycn We also show that cardiomyocytes compete according to their combined Myc and Mycn levels and that cell competition eliminates flawed cardiomyocytes, suggesting its relevance as a quality control mechanism in cardiac development.
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Proliferação de Células , Coração/embriologia , Miócitos Cardíacos/metabolismo , Proteína Proto-Oncogênica N-Myc/deficiência , Organogênese , Proteínas Proto-Oncogênicas c-myc/metabolismo , Animais , Feminino , Camundongos , Camundongos Transgênicos , Proteínas Proto-Oncogênicas c-myc/genéticaRESUMO
Myocardial infarction (MI) arising from obstruction of the coronary circulation engenders massive cardiomyocyte loss and replacement by non-contractile scar tissue, leading to pathological remodeling, dysfunction, and ultimately heart failure. This is presently a global health problem for which there is no effective cure. Following MI, the innate immune system directs the phagocytosis of dead cell debris in an effort to stimulate cell repopulation and tissue renewal. In the mammalian adult heart, however, the persistent influx of immune cells, coupled with the lack of an inherent regenerative capacity, results in cardiac fibrosis. Here, we reveal that stimulation of cardiac lymphangiogenesis with VEGF-C improves clearance of the acute inflammatory response after MI by trafficking immune cells to draining mediastinal lymph nodes (MLNs) in a process dependent on lymphatic vessel endothelial hyaluronan receptor 1 (LYVE-1). Deletion of Lyve1 in mice, preventing docking and transit of leukocytes through the lymphatic endothelium, results in exacerbation of chronic inflammation and long-term deterioration of cardiac function. Our findings support targeting of the lymphatic/immune cell axis as a therapeutic paradigm to promote immune modulation and heart repair.
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Movimento Celular , Leucócitos/metabolismo , Linfangiogênese , Sistema Linfático/metabolismo , Infarto do Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Animais , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/patologia , Inflamação/genética , Inflamação/metabolismo , Inflamação/patologia , Leucócitos/patologia , Sistema Linfático/patologia , Camundongos , Camundongos Knockout , Infarto do Miocárdio/genética , Infarto do Miocárdio/patologia , Miócitos Cardíacos/patologia , Fator C de Crescimento do Endotélio Vascular/genética , Fator C de Crescimento do Endotélio Vascular/metabolismo , Proteínas de Transporte Vesicular/genética , Proteínas de Transporte Vesicular/metabolismoRESUMO
Epicardium-derived cells (EPDCs) contribute cardiovascular cell types during development and in adulthood respond to Thymosin ß4 (Tß4) and myocardial infarction (MI) by reactivating a fetal gene programme to promote neovascularization and cardiomyogenesis. The mechanism for epicardial gene (re-)activation remains elusive. Here we reveal that BRG1, the essential ATPase subunit of the SWI/SNF chromatin-remodelling complex, is required for expression of Wilms' tumour 1 (Wt1), fetal EPDC activation and subsequent differentiation into coronary smooth muscle, and restores Wt1 activity upon MI. BRG1 physically interacts with Tß4 and is recruited by CCAAT/enhancer-binding protein ß (C/EBPß) to discrete regulatory elements in the Wt1 locus. BRG1-Tß4 co-operative binding promotes optimal transcription of Wt1 as the master regulator of embryonic EPDCs. Moreover, chromatin immunoprecipitation-sequencing reveals BRG1 binding at further key loci suggesting SWI/SNF activity across the fetal epicardial gene programme. These findings reveal essential functions for chromatin-remodelling in the activation of EPDCs during cardiovascular development and repair.
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DNA Helicases/metabolismo , Epigênese Genética , Genes do Tumor de Wilms , Coração/crescimento & desenvolvimento , Proteínas Nucleares/metabolismo , Timosina/metabolismo , Fatores de Transcrição/metabolismo , Animais , Sequência de Bases , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Montagem e Desmontagem da Cromatina , Sequência Conservada , Regulação da Expressão Gênica , Células HEK293 , Humanos , Camundongos , Camundongos Transgênicos , Infarto do Miocárdio/metabolismo , Pericárdio/citologia , Pericárdio/metabolismo , Elementos Reguladores de TranscriçãoRESUMO
Myc is an essential regulator of cell growth and proliferation. Myc overexpression promotes the homeostatic expansion of cardiomyocyte populations by cell competition, however whether this applies to other cardiac lineages remains unknown. The epicardium contributes signals and cells to the developing and adult injured heart and exploring strategies for modulating its activity is of great interest. Using inducible genetic mosaics, we overexpressed Myc in the epicardium and determined the differential expansion of Myc-overexpressing cells with respect to their wild type counterparts. Myc-overexpressing cells overcolonized all epicardial-derived lineages and showed increased ability to invade the myocardium and populate the vasculature. We also found massive colonization of the myocardium by Wt1Cre-derived Myc-overexpressing cells, with preservation of cardiac development. Detailed analyses showed that this contribution is unlikely to derive from Cre activity in early cardiomyocytes but does not either derive from established epicardial cells, suggesting that early precursors expressing Wt1Cre originate the recombined cardiomyocytes. Myc overexpression does not modify the initial distribution of Wt1Cre-recombined cardiomyocytes, indicating that it does not stimulate the incorporation of early expressing Wt1Cre lineages to the myocardium, but differentially expands this initial population. We propose that strategies using epicardial lineages for heart repair may benefit from promoting cell competitive ability.
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Coração/crescimento & desenvolvimento , Miocárdio/metabolismo , Organogênese/genética , Proteínas Proto-Oncogênicas c-myc/genética , Animais , Diferenciação Celular/genética , Linhagem da Célula/genética , Proliferação de Células/genética , Vasos Coronários/crescimento & desenvolvimento , Vasos Coronários/metabolismo , Vasos Coronários/patologia , Regulação da Expressão Gênica no Desenvolvimento , Integrases/genética , Camundongos , Miócitos Cardíacos/metabolismo , Pericárdio/crescimento & desenvolvimento , Pericárdio/metabolismoRESUMO
Heterogeneous anabolic capacity in cell populations can trigger a phenomenon known as cell competition, through which less active cells are eliminated. Cell competition has been induced experimentally in stem/precursor cell populations in insects and mammals and takes place endogenously in early mouse embryonic cells. Here, we show that cell competition can be efficiently induced in mouse cardiomyocytes by mosaic overexpression of Myc during both gestation and adult life. The expansion of the Myc-overexpressing cardiomyocyte population is driven by the elimination of wild-type cardiomyocytes. Importantly, this cardiomyocyte replacement is phenotypically silent and does not affect heart anatomy or function. These results show that the capacity for cell competition in mammals is not restricted to stem cell populations and suggest that stimulated cell competition has potential as a cardiomyocyte-replacement strategy.
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Coração/fisiologia , Miócitos Cardíacos/citologia , Animais , Apoptose , Embrião de Mamíferos/metabolismo , Feminino , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Coração/anatomia & histologia , Coração/crescimento & desenvolvimento , Proteína Homeobox Nkx-2.5 , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Integrases/genética , Integrases/metabolismo , Proteínas com Homeodomínio LIM/metabolismo , Masculino , Camundongos , Miócitos Cardíacos/metabolismo , Fenótipo , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Recombinação Genética , Células-Tronco/citologia , Células-Tronco/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
The first blood and endothelial cells of amniote embryos appear in close association in the blood islands of the yolk sac (YS). This association and in vitro lineage analyses have suggested a common origin from mesodermal precursors called hemangioblasts, specified in the primitive streak during gastrulation. Fate mapping and chimera studies, however, failed to provide strong evidence for a common origin in the early mouse YS. Additional in vitro studies suggest instead that mesodermal precursors first generate hemogenic endothelium, which then generate blood cells in a linear sequence. We conducted an in vivo clonal analysis to determine the potential of individual cells in the mouse epiblast, primitive streak, and early YS. We found that early YS blood and endothelial lineages mostly derive from independent epiblast populations, specified before gastrulation. Additionally, a subpopulation of the YS endothelium has hemogenic activity and displays characteristics similar to those found later in the embryonic hemogenic endothelium. Our results show that the earliest blood and endothelial cell populations in the mouse embryo are specified independently, and that hemogenic endothelium first appears in the YS and produces blood precursors with markers related to definitive hematopoiesis.