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This study aims to investigate the differences in intra-urban catchments with different characteristics through real-time wastewater monitoring. Monitoring stations were installed in three neighbourhoods of Barcelona to measure flow, total chemical oxygen demand (COD), pH, conductivity, temperature, and bisulfide (HS-) for 1 year. Typical wastewater profiles were obtained for weekdays, weekends, and holidays in the summer and winter seasons. The results reveal differences in waking up times and evening routines, commuting behaviour during weekends and holidays, and water consumption. The pollutant profiles contribute to a better understanding of pollution generation in households and catchment activities. Flows and COD correlate well at all stations, but there are differences in conductivity and HS- at the station level. The article concludes by discussing the operational experience of the monitoring stations.
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Monitoramento Ambiental , Águas Residuárias , Monitoramento Ambiental/métodos , Esgotos/análise , Chuva , Análise da Demanda Biológica de Oxigênio , CidadesRESUMO
Red cell distribution width (RDW) is a measure of the variation in mean corpuscular volume that reflects the degree of anisocytosis on the peripheral blood smear. RDW value variation has been implicated in several disorders including chronic inflammatory processes and cardiovascular (CV) diseases. In the present work, our objective was to study the relationship that RDW has with the characteristics of the disease in patients with rheumatoid arthritis (RA), focusing on CV risk factors and subclinical atherosclerosis. A cross-sectional study was conducted that included 430 patients with RA and 208 controls matched by sex and age. Complete blood count, including RDW, was assessed. Multivariable analysis was performed to analyze the relationship of RDW with RA disease characteristics, subclinical carotid atherosclerosis, and traditional CV factors, including a comprehensive profile of lipid molecules and insulin resistance and beta cell function indices. After multivariable adjustment, the RDW was significantly higher in RA patients compared with controls (beta coefficient 1.0 [95% confidence interval 0.2 to 1.8] %, p = 0.020). Furthermore, although the erythrocyte sedimentation rate showed a positive and significant relationship with RDW, this association was not found with C-reactive protein and interleukin-6. A positive and independent relationship was observed between DAS28-ESR disease activity score and RDW. However, no association was found between the RDW and other disease activity scores that do not include erythrocyte sedimentation rate in their formula. The SCORE2 CV risk algorithm was positively and significantly associated with higher RDW values. Likewise, a negative relationship was found between RDW with total cholesterol and low-density lipoprotein cholesterol, and a positive relationship was found between RDW and insulin resistance indices. In conclusion, RDW values are higher in RA patients compared to matched controls. Although the relationship of RDW with disease activity was not consistent, RDW shows associations with subclinical CV disease risk factors, including dyslipidemia and insulin resistance, and with the SCORE2 CV disease-risk prediction algorithm.
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The monocytes to high-density lipoprotein (HDL)-cholesterol ratio (MHR) indicates inflammation based on the anti-inflammatory properties of HDL-cholesterol as well as the pro-inflammatory effect of monocytes. Several studies have investigated MHR in various disorders, specifically in cardiovascular diseases. Consequently, MHR has been significantly associated with cardiovascular and all-cause mortality in the general population, regardless of established risk factors. However, its role in the augmented risk of cardiovascular disease found in rheumatoid arthritis (RA) has not been studied to date. This is a cross-sectional study that encompassed 430 patients with RA and 208 controls matched by sex and age. Complete blood cell count and complete lipid profile were evaluated. Multivariable analysis was made to analyze the relationship between MHR and RA disease and features subclinical carotid atherosclerosis, and traditional CV factors including insulin resistance and beta cell function indices. MHR values did not differ between controls and patients after multivariable adjustment (12 ± 6 vs. 11 ± 6, p = 0.18). No relationship between this ratio and the characteristics of the disease was found excluding ESR, which showed a significant and positive association with MHR after adjustment for covariates. MHR significantly correlated with Systematic Coronary Risk Evaluation-2 (SCORE2) cardiovascular risk algorithm, and insulin resistance and beta cell function parameters after adjustment. In conclusion, MHR does not differ between patients with RA and controls. The relationship of this biomarker with disease-related data is poor. However, MHR is highly and positively related to cardiovascular risk and insulin resistance in RA.
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Mean platelet volume (MPV) refers to the average platelet size in femtoliters. Increased or decreased MPV has been associated with several disorders, including inflammatory and cardiovascular diseases. In the present study, our objective was to analyze the relationship of MPV with disease activity in a large and well-characterized series of patients with rheumatoid arthritis (RA). This is a cross-sectional study that included 315 patients with RA and 208 controls matched by sex and age. Complete blood count, including MPV, was assessed. Multivariable analysis was performed to examine the relationship of MPV with RA disease characteristics, carotid atherosclerosis, and traditional cardiovascular factors, including a comprehensive profile of lipid molecules and insulin resistance or beta cell function indices. The multivariable analysis, which includes other hematological modifications produced by the disease and platelet values, showed that MPV levels were significantly lower in RA patients than in controls. Erythrocyte sedimentation rate and interleukin-6, but not C-reactive protein, were negatively correlated with MPV after adjustment for covariates. Similarly, disease activity and MPV had a significant and independent negative correlation. No relationships were found between MPV and cardiovascular risk factors, lipid profile or insulin resistance indices or subclinical atherosclerosis. In conclusion, patients with RA have lower levels of MPV than controls. MPV is negatively related to acute phase reactants and disease activity in RA.
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The neutrophil-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), platelet-to-lymphocyte ratio (PLR), and systemic immune-inflammatory index (SIRI, neutrophils × monocytes/lymphocytes) have been described as potential blood-derived inflammatory biomarkers in several diseases. Rheumatoid arthritis is an inflammatory disease that has been related to an increased risk of cardiovascular (CV) disease. In the present work, we analyze how these hematological composite scores of inflammation are related to classic CV risk factors and subclinical atherosclerosis in patients with RA. In this cross-sectional study that included 430 patients with RA, the NLR, MLR, PLR, and SIRI scores were calculated. Multivariable analysis was performed to examine the relationships of these composite blood scores with subclinical carotid atherosclerosis and with traditional cardiovascular factors, producing a complete profile of lipid molecules and insulin resistance or indices of beta-cell function, and a Systematic Coronary Risk Assessment (SCORE2) calculation. C-reactive protein and disease activity were significantly and positively associated with the four blood composite scores. SCORE2 was significantly associated with higher values of SIRI, NLR, and MLR, but not PLR. These relationships were maintained when SCORE 2 was considered categorical; patients in the very high CV risk category had higher values in all hematological composite scores, except PLR. In the multivariable analysis, SIRI and NLR were independently associated with higher levels of beta cell dysfunction. In conclusion, SCORE2 and the values of the hematological composite scores were positively correlated in patients with RA. In addition, there were some relationships of these scores with traditional CV risk factors, with their association with beta cell dysfunction being the most consistent.
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Introduction: Nowadays, a set of novel physiotherapy techniques have emerged, in which the physical agent used to try to reduce spasticity is applied percutaneously, specifically, through the patient's skin. The aim of this work is to encompass all the invasive techniques used in spasticity in a single article, updating the existing bibliography. Methodology: A systematic review was carried out between December 2020 and April 2021 in the Web of Science, Scopus and PubMed databases, selecting the clinical trials that used acupuncture, electroacupuncture or dry needling as a treatment for spasticity. Sixteen clinical trials were included, summarizing all the study characteristics and the outcome measures, at last the evidence was described for their results. Results: Most of the studies find a difference of significant decrease in spasticity between the subjects of the experimental groups. Only four studies found no significant changes in spasticity. All the studies are carried out together with the conventional physiotherapy treatment in spasticity. Conclusion: Treatment with invasive physiotherapy, combined with conventional physiotherapy, seems to have positive effects in reducing spasticity, although more studies are needed to improve the heterogeneity of the interventions and to assess their long-term effectiveness.
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Mental health in later life and suicide risk among older adults are important topics for social work. There is evidence-based research to support the use selective and indicated strategies for suicide prevention, yet, universal prevention approaches are also needed. However, the extent to which the broader contexts of suicide have been examined remains largely absent from the literature. This article presents findings from a systematic review of articles published between 2009 and 2021, focusing what types of empirically evaluated suicide prevention programs effectively prevent and reduce suicidality in older adults. Using the PICO and PRISMA guidelines, a final sample of 8 articles were reviewed in this systematic review. The articles were categorized into three types of programs: 1) primary and home health care, 2) community-based outreach, and 3) counseling. The articles also examined the involvement of social workers in these programs. Following a description of the articles, the authors assess each study using the GRADE rating system. Lastly, the authors discuss the role of the social worker in mental health promotion and prevention strategies.
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Prevenção do Suicídio , Idoso , Promoção da Saúde , Humanos , Saúde Mental , Avaliação de Programas e Projetos de SaúdeRESUMO
Twenty million people live with a sickle cell disease (SCD) diagnosis globally; about 100,000 reside in the United States of America (US). Although SCD continues to threaten the health, mostly of particular groups in the US, there is a lack of knowledge on risk factors such as unawareness of carrier status, inheritance patterns, and resistance to SCT screening among childbearing age individuals. A cross-sectional survey design using a modified version of the Health Belief Survey assessed college students' SCD beliefs and screening behaviors. Four hundred sixteen students from a North Texas university campus participated in the survey. Although most participants believed that knowing their carrier status was important, only 26% were aware of their status. Findings demonstrated that health beliefs were a significant predictor of screening behaviors. The Universal, Selective, and Indicated Prevention Approach was suggested as a suitable approach to educate, transform health beliefs, and augment screening participation.
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Conhecimentos, Atitudes e Prática em Saúde , Estudantes , Estudos Transversais , Humanos , Programas de Rastreamento , Inquéritos e Questionários , Estados UnidosRESUMO
Pluripotent stem cells (PSCs) transition between cell states in vitro, reflecting developmental changes in the early embryo. PSCs can be stabilized in the naive state by blocking extracellular differentiation stimuli, particularly FGF-MEK signalling. Here, we report that multiple features of the naive state in human and mouse PSCs can be recapitulated without affecting FGF-MEK signalling or global DNA methylation. Mechanistically, chemical inhibition of CDK8 and CDK19 (hereafter CDK8/19) kinases removes their ability to repress the Mediator complex at enhancers. CDK8/19 inhibition therefore increases Mediator-driven recruitment of RNA polymerase II (RNA Pol II) to promoters and enhancers. This efficiently stabilizes the naive transcriptional program and confers resistance to enhancer perturbation by BRD4 inhibition. Moreover, naive pluripotency during embryonic development coincides with a reduction in CDK8/19. We conclude that global hyperactivation of enhancers drives naive pluripotency, and this can be achieved in vitro by inhibiting CDK8/19 kinase activity. These principles may apply to other contexts of cellular plasticity.
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Diferenciação Celular , Quinase 8 Dependente de Ciclina/antagonistas & inibidores , Quinases Ciclina-Dependentes/antagonistas & inibidores , Metilação de DNA , Elementos Facilitadores Genéticos , Células-Tronco Pluripotentes/citologia , Animais , Quinase 8 Dependente de Ciclina/genética , Quinase 8 Dependente de Ciclina/metabolismo , Quinases Ciclina-Dependentes/genética , Quinases Ciclina-Dependentes/metabolismo , Feminino , Humanos , Camundongos , Fosforilação , Células-Tronco Pluripotentes/metabolismo , Regiões Promotoras Genéticas , RNA Polimerase II/genética , RNA Polimerase II/metabolismo , Transdução de SinaisRESUMO
The presence of nanomaterials in our everyday life is ever increasing, and so too are concerns about the possible health consequences of exposure to them. While evidence of their biological activity is growing, there is still scant knowledge of the epigenetic mechanisms that could be at play in these processes. Moreover, the great variability in the chemical and physical structures of these compounds handicaps the study of their possible health risks. Here we have synthesized reduced graphene oxide (rGO) through the thermal exfoliation/reduction of graphite oxide, and characterized the resulting material. We have then made use of Illumina's MethylationEPIC arrays and bisulphite pyrosequencing to analyse the genome-wide and global DNA methylation dynamics associated with the medium-term exposure of human lung epithelial cells to rGO at concentrations of 1 and 10 µg/mL. The results show no genome-wide or global DNA methylation changes associated with either condition. Our observations thus suggest that medium-term rGO exposure does not have significant effects on the DNA methylation patterns of human lung epithelial cells.
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Células Epiteliais Alveolares/efeitos dos fármacos , Metilação de DNA , Epigenoma , Grafite/toxicidade , Nanoestruturas/toxicidade , Células Epiteliais Alveolares/metabolismo , Células Cultivadas , Grafite/farmacologia , HumanosRESUMO
Loss of 5-hydroxymethylcytosine (5hmC) has been associated with mutations of the ten-eleven translocation (TET) enzymes in several types of cancer. However, tumors with wild-type TET genes can also display low 5hmC levels, suggesting that other mechanisms involved in gene regulation might be implicated in the decline of this epigenetic mark. Here we show that DNA hypermethylation and loss of DNA hydroxymethylation, as well as a marked reduction of activating histone marks in the TET3 gene, impair TET3 expression and lead to a genome-wide reduction in 5hmC levels in glioma samples and cancer cell lines. Epigenetic drugs increased expression of TET3 in glioblastoma cells and ectopic overexpression of TET3 impaired in vitro cell growth and markedly reduced tumor formation in immunodeficient mice models. TET3 overexpression partially restored the genome-wide patterns of 5hmC characteristic of control brain samples in glioblastoma cell lines, while elevated TET3 mRNA levels were correlated with better prognosis in glioma samples. Our results suggest that epigenetic repression of TET3 might promote glioblastoma tumorigenesis through the genome-wide alteration of 5hmC.
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Neoplasias Encefálicas/genética , Carcinogênese/genética , Dioxigenases/genética , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Glioblastoma/genética , 5-Metilcitosina/análogos & derivados , 5-Metilcitosina/metabolismo , Animais , Biópsia , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Metilação de DNA , Regulação para Baixo , Glioblastoma/mortalidade , Glioblastoma/patologia , Código das Histonas/genética , Humanos , Camundongos , Prognóstico , RNA Mensageiro/metabolismo , Análise de Sobrevida , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
CONTEXT: SDHB mutations are found in an increasing number of neoplasms, most notably in paragangliomas and pheochromocytomas (PPGLs). SDHB-PPGLs are slow-growing tumors, but â¼50% of them may develop metastasis. The molecular basis of metastasis in these tumors is a long-standing and unresolved problem. Thus, a better understanding of the biology of metastasis is needed. OBJECTIVE: This study aimed to identify gene methylation changes relevant for metastatic SDHB-PPGLs. DESIGN: We performed genome-wide profiling of DNA methylation in diverse clinical and genetic PPGL subtypes, and validated protocadherin γ-C3 (PCDHGC3) gene promoter methylation in metastatic SDHB-PPGLs. RESULTS: We define an epigenetic landscape specific for metastatic SDHB-PPGLs. DNA methylation levels were found significantly higher in metastatic SDHB-PPGLs than in SDHB-PPGLs without metastases. One such change included long-range de novo methylation of the PCDHA, PCDHB, and PCDHG gene clusters. High levels of PCDHGC3 promoter methylation were validated in primary metastatic SDHB-PPGLs, it was found amplified in the corresponding metastases, and it was significantly correlated with PCDHGC3 reduced expression. Interestingly, this epigenetic alteration could be detected in primary tumors that developed metastasis several years later. We also show that PCDHGC3 down regulation engages metastasis-initiating capabilities by promoting cell proliferation, migration, and invasion. CONCLUSIONS: Our data provide a map of the DNA methylome episignature specific to an SDHB-mutated cancer and establish PCDHGC3 as a putative suppressor gene and a potential biomarker to identify patients with SDHB-mutated cancer at high risk of metastasis who might benefit from future targeted therapies.
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Neoplasias das Glândulas Suprarrenais/genética , Caderinas/genética , Epigênese Genética , Mutação , Paraganglioma/genética , Feocromocitoma/genética , Succinato Desidrogenase/genética , Neoplasias das Glândulas Suprarrenais/metabolismo , Neoplasias das Glândulas Suprarrenais/patologia , Proteínas Relacionadas a Caderinas , Caderinas/metabolismo , Movimento Celular/genética , Proliferação de Células/genética , Feminino , Humanos , Masculino , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Paraganglioma/metabolismo , Paraganglioma/patologia , Feocromocitoma/metabolismo , Feocromocitoma/patologia , Succinato Desidrogenase/metabolismoRESUMO
Histone H4 acetylation at Lysine 16 (H4K16ac) is a key epigenetic mark involved in gene regulation, DNA repair and chromatin remodeling, and though it is known to be essential for embryonic development, its role during adult life is still poorly understood. Here we show that this lysine is massively hyperacetylated in peripheral neutrophils. Genome-wide mapping of H4K16ac in terminally differentiated blood cells, along with functional experiments, supported a role for this histone post-translational modification in the regulation of cell differentiation and apoptosis in the hematopoietic system. Furthermore, in neutrophils, H4K16ac was enriched at specific DNA repeats. These DNA regions presented an accessible chromatin conformation and were associated with the cleavage sites that generate the 50 kb DNA fragments during the first stages of programmed cell death. Our results thus suggest that H4K16ac plays a dual role in myeloid cells as it not only regulates differentiation and apoptosis, but it also exhibits a non-canonical structural role in poising chromatin for cleavage at an early stage of neutrophil cell death.
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Apoptose , Diferenciação Celular , Cromatina/metabolismo , Histonas/metabolismo , Lisina/metabolismo , Células Mieloides/metabolismo , Acetilação , Animais , Células Cultivadas , Cromatina/genética , Epigênese Genética , Humanos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células Mieloides/citologia , Processamento de Proteína Pós-Traducional , Transcrição GênicaRESUMO
X-linked myotubular myopathy (XLMTM, also known as XLCNM) is a severe congenital muscular disorder due to mutations in the myotubularin gene, MTM1. It is characterized by generalized hypotonia, leading to neonatal death of most patients. No specific treatment exists. Here, we show that tamoxifen, a well-known drug used against breast cancer, rescues the phenotype of Mtm1-deficient mice. Tamoxifen increases lifespan several-fold while improving overall motor function and preventing disease progression including lower limb paralysis. Tamoxifen corrects functional, histological and molecular hallmarks of XLMTM, with improved force output, myonuclei positioning, myofibrillar structure, triad number, and excitation-contraction coupling. Tamoxifen normalizes the expression level of the XLMTM disease modifiers DNM2 and PI3KC2B, likely contributing to the phenotypic rescue. Our findings demonstrate that tamoxifen is a promising candidate for clinical evaluation in XLMTM patients.
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Atividade Motora/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Miopatias Congênitas Estruturais/tratamento farmacológico , Substâncias Protetoras/farmacologia , Proteínas Tirosina Fosfatases não Receptoras/genética , Tamoxifeno/farmacologia , Animais , Classe II de Fosfatidilinositol 3-Quinases/genética , Classe II de Fosfatidilinositol 3-Quinases/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Dinamina II/genética , Dinamina II/metabolismo , Estimulação Elétrica , Acoplamento Excitação-Contração/efeitos dos fármacos , Feminino , Expressão Gênica/efeitos dos fármacos , Genes Letais , Humanos , Longevidade/efeitos dos fármacos , Masculino , Camundongos , Camundongos Knockout , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Miofibrilas/efeitos dos fármacos , Miofibrilas/metabolismo , Miofibrilas/ultraestrutura , Miopatias Congênitas Estruturais/genética , Miopatias Congênitas Estruturais/metabolismo , Miopatias Congênitas Estruturais/patologia , Proteínas Tirosina Fosfatases não Receptoras/deficiênciaRESUMO
Ten-eleven translocation (TET) enzymes are frequently deregulated in cancer, but the underlying molecular mechanisms are still poorly understood. Here we report that TET2 shows frequent epigenetic alterations in human glioblastoma including DNA hypermethylation and hypo-hydroxymethylation, as well as loss of histone acetylation. Ectopic overexpression of TET2 regulated neural differentiation in glioblastoma cell lines and impaired tumor growth. Our results suggest that epigenetic dysregulation of TET2 plays a role in human glioblastoma.
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Aberrant DNA hypermethylation is a hallmark of cancer although the underlying molecular mechanisms are still poorly understood. To study the possible role of 5-hydroxymethylcytosine (5hmC) in this process we analyzed the global and locus-specific genome-wide levels of 5hmC and 5-methylcytosine (5mC) in human primary samples from 12 non-tumoral brains and 53 gliomas. We found that the levels of 5hmC identified in non-tumoral samples were significantly reduced in gliomas. Strikingly, hypo-hydroxymethylation at 4627 (9.3%) CpG sites was associated with aberrant DNA hypermethylation and was strongly enriched in CpG island shores. The DNA regions containing these CpG sites were enriched in H3K4me2 and presented a different genuine chromatin signature to that characteristic of the genes classically aberrantly hypermethylated in cancer. As this 5mC gain is inversely correlated with loss of 5hmC and has not been identified with classical sodium bisulfite-based technologies, we conclude that our data identifies a novel 5hmC-dependent type of aberrant DNA hypermethylation in glioma.
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5-Metilcitosina/análogos & derivados , Biomarcadores Tumorais/genética , Metilação de DNA , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Genoma Humano , Glioma/patologia , 5-Metilcitosina/metabolismo , Estudos de Casos e Controles , Ilhas de CpG , Glioma/genética , Glioma/metabolismo , HumanosRESUMO
The poor correlation of mutational landscapes with phenotypes limits our understanding of the pathogenesis and metastasis of pancreatic ductal adenocarcinoma (PDAC). Here we show that oncogenic dosage-variation has a critical role in PDAC biology and phenotypic diversification. We find an increase in gene dosage of mutant KRAS in human PDAC precursors, which drives both early tumorigenesis and metastasis and thus rationalizes early PDAC dissemination. To overcome the limitations posed to gene dosage studies by the stromal richness of PDAC, we have developed large cell culture resources of metastatic mouse PDAC. Integration of cell culture genomes, transcriptomes and tumour phenotypes with functional studies and human data reveals additional widespread effects of oncogenic dosage variation on cell morphology and plasticity, histopathology and clinical outcome, with the highest KrasMUT levels underlying aggressive undifferentiated phenotypes. We also identify alternative oncogenic gains (Myc, Yap1 or Nfkb2), which collaborate with heterozygous KrasMUT in driving tumorigenesis, but have lower metastatic potential. Mechanistically, different oncogenic gains and dosages evolve along distinct evolutionary routes, licensed by defined allelic states and/or combinations of hallmark tumour suppressor alterations (Cdkn2a, Trp53, Tgfß-pathway). Thus, evolutionary constraints and contingencies direct oncogenic dosage gain and variation along defined routes to drive the early progression of PDAC and shape its downstream biology. Our study uncovers universal principles of Ras-driven oncogenesis that have potential relevance beyond pancreatic cancer.
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Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Evolução Molecular , Dosagem de Genes , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Alelos , Animais , Carcinogênese/genética , Proteínas de Ciclo Celular , Inibidor p16 de Quinase Dependente de Ciclina/genética , Progressão da Doença , Feminino , Genes myc , Genes p53 , Humanos , Masculino , Camundongos , Mutação , Subunidade p52 de NF-kappa B/genética , Metástase Neoplásica/genética , Proteínas Nucleares/genética , Fenótipo , Fosfoproteínas/genética , Fatores de Transcrição/genética , Transcriptoma/genética , Fator de Crescimento Transformador beta1/genética , Proteínas de Sinalização YAPRESUMO
Patterns of DNA methylation, an important epigenetic modification involved in gene silencing and development, are disrupted in cancer cells. Understanding the functional significance of aberrant methylation in tumors remains challenging, due in part to the lack of suitable tools to actively modify methylation patterns. DNA demethylation caused by mammalian DNA methyltransferase inhibitors is transient and replication-dependent, whereas that induced by TET enzymes involves oxidized 5mC derivatives that perform poorly understood regulatory functions. Unlike animals, plants possess enzymes that directly excise unoxidized 5mC from DNA, allowing restoration of unmethylated C through base excision repair. Here, we show that expression of Arabidopsis 5mC DNA glycosylase DEMETER (DME) in colon cancer cells demethylates and reactivates hypermethylated silenced loci. Interestingly, DME expression causes genome-wide changes that include both DNA methylation losses and gains, and partially restores the methylation pattern observed in normal tissue. Furthermore, such methylome reprogramming is accompanied by altered cell cycle responses and increased sensibility to anti-tumor drugs, decreased ability to form colonospheres, and tumor growth impairment in vivo. Our study shows that it is possible to reprogram a human cancer DNA methylome by expression of a plant DNA demethylase.
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Proteínas de Arabidopsis/genética , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/genética , Metilação de DNA , N-Glicosil Hidrolases/genética , Transativadores/genética , Animais , Antineoplásicos/farmacologia , Proteínas de Arabidopsis/metabolismo , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Linhagem Celular Tumoral , Neoplasias do Colo/patologia , Reparo do DNA/genética , Fluoruracila/farmacologia , Regulação Neoplásica da Expressão Gênica , Genes Supressores de Tumor , Genes p16 , Humanos , Camundongos Nus , N-Glicosil Hidrolases/metabolismo , Proteínas Oncogênicas/genética , Oxaliplatina/farmacologia , Receptores Órfãos Semelhantes a Receptor Tirosina Quinase/genética , Transativadores/metabolismo , Transgenes , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
PURPOSE: To study the functional recovery of the superior rectus muscle (SRM) after its partial resection in a rabbit model with and without cryopreserved amniotic membrane (AM). MATERIAL AND METHODS: Resection of the right and left SRMs of 30 rabbits was performed. On the left eyes, a single sheet of equine cryopreserved AM was placed covering the muscle edge sutured. Active and passive mechanical properties of muscles operated with and without AM were monitored over time at 30 (n = 10), 60 (n = 10), and 90 (n = 10) days after surgery. Muscle samples were extracted and electrically stimulated to register the force exerted by the samples, characterizing its active behavior. They were, then, subjected to stretching test to obtain its resistance to deformation, known as passive behavior. Moreover, right and left eyes of a control group (n = 5) were equally subjected to active and passive tests to characterize the physiological behavior of SRM muscles. RESULTS: On active function examination, statistically significant differences were documented between the following: control vs AM and no AM at 30 days (p = 0.002 and p = 0.04, respectively). All other comparisons were insignificant (p > 0.05). On passive function analysis, significant differences were only found between control vs. no AM at 30 days (p = 0.004) and between AM vs. no AM at 30 days (p = 0.002). Indeed, muscle operated without AM did not recover a normal passive function until 60 days after surgery. CONCLUSION: Cryopreserved AM is effective in accelerating recovery of SRM passive function in rabbits. Nevertheless, AM produced no significant effect on recovery of SRM active function..
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Âmnio , Criopreservação , Músculos Oculomotores/fisiologia , Músculos Oculomotores/cirurgia , Estrabismo/cirurgia , Transplante de Tecidos , Animais , Fenômenos Biomecânicos , Masculino , Procedimentos Cirúrgicos Oftalmológicos , Coelhos , Recuperação de Função Fisiológica/fisiologia , Estrabismo/fisiopatologiaRESUMO
Context: Germline mutations in the succinate dehydrogenase A, B, C, and D genes (collectively, SDHx) predispose to the development of paragangliomas (PGLs) arising at the parasympathetic or sympathetic neuroendocrine systems. SDHx mutations cause absence of tumoral immunostaining for SDHB. However, negative SDHB immunostaining has also been found in a subset of PGLs that lack SDHx mutations. Settings: Here, we report the comprehensive molecular characterization of one such a tumor of parasympathetic origin compared with healthy paraganglia and other PGLs with or without SDHx mutations. Results: Integration of multiplatform data revealed somatic SDHC methylation and loss of the 1q23.3 region containing the SDHC gene. This correlated with decreased SDHC messenger RNA (mRNA) and protein levels. Furthermore, another genetic event found affected the VHL gene, which showed a decreased DNA copy number, associated with low VHL mRNA levels, and an absence of VHL protein detected by immunohistochemistry. In addition, the tumor displayed a pseudohypoxic phenotype consisting in overexpression of the hypoxia-inducible factor (HIF)-1α and miR-210, as well as downregulation of the iron-sulfur cluster assembly enzyme (ISCU) involved in SDHB maturation. This profile resembles that of SDHx- or VHL-mutated PGLs but not of PGLs with decreased VHL copy number, pointing to SDHC rather than VHL as the pathogenic driver. Conclusions: Collectively, these findings demonstrate the potential importance of both the SDHC epigenomic event and the activation of the HIF-1α/miR-210/ISCU axis in the pathogenesis of SDHx wild-type/SDHB-negative PGLs. To our knowledge, this is the first case of a sporadic parasympathetic PGL that carries silencing of SDHC, fulfilling the two-hit Knudson's model for tumorigenesis.