RESUMO
We tested the hypothesis that fixed oral moderate-dose hydroxyurea (20 mg/kg per day) for initial treatment of secondary stroke prevention results in an 80% relative risk reduction of stroke or death when compared with fixed oral low-dose hydroxyurea (10 mg/kg per day) in a phase 3 double-blind, parallel-group, randomized controlled trial in children with sickle cell anemia (SCA) living in Nigeria. A total of 101 participants were randomly allocated to low-dose (n = 49) and moderate-dose (n = 52) hydroxyurea treatment groups. The median participant follow-up was 1.6 years (interquartile range, 1.0-2.3), with a planned minimum follow-up of 3.0 years. A total of 6 recurrent strokes and 2 deaths vs 5 recurrent strokes and 3 deaths occurred in the low- and moderate-dose groups, respectively. The incidence rate ratio (IRR) of the primary outcome measure of stroke or death in the low- and moderate-dose hydroxyurea treatment groups was 0.98 (95% confidence interval [CI], 0.32-3.00; P = .97). The trial was stopped early owing to no clinical difference in the incidence rates of the primary outcome measure. The incidence rates of recurrent strokes were 7.1 and 6.0 per 100 person-years in the low- and moderate-dose groups, respectively, (IRR, 1.18; 95% CI, 0.30-4.88; P = .74). As a measure of adherence to the oral hydroxyurea therapy, the median percent of returned pills was 3.0% and 2.6% in the low- and moderate-dose groups, respectively. No participant had hydroxyurea therapy stopped for myelosuppression. For children with SCA in low-income settings without access to regular blood transfusion therapy, initial low-dose hydroxyurea is a minimum known efficacious dose for secondary stroke prevention.
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Anemia Falciforme , Acidente Vascular Cerebral , Criança , Humanos , Hidroxiureia/uso terapêutico , Antidrepanocíticos/uso terapêutico , Nigéria , Anemia Falciforme/complicações , Acidente Vascular Cerebral/etiologia , Prevenção Secundária/métodosRESUMO
Oral iron supplementation in iron deficient children with sickle cell anemia and normal transcranial Doppler ultrasound (TCD) velocities does not reduce arterial flow in the middle cerebral artery.
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Anemia Falciforme , Acidente Vascular Cerebral , Criança , Humanos , Velocidade do Fluxo Sanguíneo , Anemia Falciforme/complicações , Anemia Falciforme/diagnóstico por imagem , Ultrassonografia Doppler Transcraniana , Circulação CerebrovascularRESUMO
Bisphenol A (BPA) is an essential and extensively utilized chemical compound with significant environmental and public health risks. This review critically assesses the current water purification techniques for BPA removal, emphasizing the efficacy of adsorption technology. Within this context, we probe into the synthesis of magnetic biochar (MBC) using co-precipitation, hydrothermal carbonization, mechanical ball milling, and impregnation pyrolysis as widely applied techniques. Our analysis scrutinizes the strengths and drawbacks of these techniques, with pyrolytic temperature emerging as a critical variable influencing the physicochemical properties and performance of MBC. We explored various modification techniques including oxidation, acid and alkaline modifications, element doping, surface functional modification, nanomaterial loading, and biological alteration, to overcome the drawbacks of pristine MBC, which typically exhibits reduced adsorption performance due to its magnetic medium. These modifications enhance the physicochemical properties of MBC, enabling it to efficiently adsorb contaminants from water. MBC is efficient in the removal of BPA from water. Magnetite and maghemite iron oxides are commonly used in MBC production, with MBC demonstrating effective BPA removal fitting well with Freundlich and Langmuir models. Notably, the pseudo-second-order model accurately describes BPA removal kinetics. Key adsorption mechanisms include pore filling, electrostatic attraction, hydrophobic interactions, hydrogen bonding, π-π interactions, and electron transfer surface interactions. This review provides valuable insights into BPA removal from water using MBC and suggests future research directions for real-world water purification applications.
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Compostos Benzidrílicos , Carvão Vegetal , Fenóis , Águas Residuárias , Poluentes Químicos da Água , Purificação da Água , Carvão Vegetal/química , Compostos Benzidrílicos/química , Compostos Benzidrílicos/análise , Fenóis/análise , Fenóis/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química , Purificação da Água/métodos , Adsorção , Águas Residuárias/química , Eliminação de Resíduos Líquidos/métodosRESUMO
BACKGROUND: Studies investigating the diagnostic and prognostic value of the neutrophil-to-lymphocyte ratio (NLR) in sepsis or septic shock commonly included preselected subgroups of patients or were published prior to the current sepsis-3 criteria. Therefore, this study investigates the diagnostic and prognostic impact of the NLR in patients with sepsis and septic shock. METHODS: Consecutive patients with sepsis and septic shock from 2019 to 2021 from the prospective "MARSS-registry" were included monocentrically. First, the diagnostic value of the NLR compared to established sepsis scores was tested for septic shock compared to sepsis. Second, the diagnostic value of the NLR with regard to positive blood cultures was tested. Thereafter, the prognostic value of the NLR was tested for 30-day all-cause mortality. Statistical analyses included univariable t-tests, Spearman´s correlations, C-statistics, Kaplan-Meier analyses, Cox proportional regression analyses as well as uni- and multivariate logistic regression models. RESULTS: A total of 104 patients were included, of which 60% were admitted with sepsis and 40% with septic shock. The overall rate of all-cause mortality at 30 days was 56%. With an area under the curve (AUC) of 0.492, the NLR was shown to have a poor diagnostic value with regard to the diagnosis of septic shock compared to sepsis. However, the NLR was shown to be a reliable parameter to discriminate between patients with negative and positive blood cultures when admitted with septic shock (AUC = 0.714). This was still evident after multivariable adjustment (OR = 1.025; 95% CI 1.000 - 1.050; p = 0.048). In contrast, the NLR revealed a poor prognostic accuracy (AUC = 0.507) with regard to 30-day all-cause mortality. Finally, a higher NLR was not associated with an increased risk of 30-day all-cause mortality (log rank p-value = 0.775). CONCLUSIONS: The NLR was a reliable diagnostic tool for the identification of patients with blood culture confirmed sepsis. Yet, the NLR was not a reliable parameter to discriminate between patients with sepsis and septic shock nor between 30-day survivors and non-survivors.
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Sepse , Choque Séptico , Humanos , Prognóstico , Neutrófilos , Estudos Prospectivos , Linfócitos , Estudos Retrospectivos , Curva ROCRESUMO
The study investigates the prognostic significance of beta-blocker (BB) dose in patients with ventricular tachyarrhythmias. Limited data regarding the prognostic impact of BB dose in ventricular tachyarrhythmias is available. A large retrospective registry was used including consecutive patients on BB treatment with episodes of ventricular tachycardia (VT) or fibrillation (VF) from 2002 to 2015. Discharge BB doses were grouped as > 0-12.5%, > 12.5-25%, > 25-50%, and > 50% according to doses used in randomized trials. The primary endpoint was all-cause mortality at three years. Secondary endpoints comprised of a composite arrhythmic endpoint (i.e., recurrences of ventricular tachyarrhythmias and appropriate ICD therapies) and cardiac rehospitalization. Kaplan-Meier survival curves and multivariable Cox regression analyses were applied for statistics. A total of 1313 patients with BB were included; most patients were discharged with > 25-50% of BB target dose (59%). At three years, > 12.5-25% of BB target dose was associated with improved long-term mortality as compared to the > 0-12.5% group (HR = 0.489; 95% CI 0.297-0.806; p = 0.005), whereas higher BB doses did not improve survival (> 25-50%: HR = 0.849; p = 0.434; > 50%: HR = 0.735; p = 0.285). In contrast, the composite endpoint and risk of rehospitalization were not affected by BB target dose. In conclusion, > 12.5-25% of BB target dose is associated with best long-term survival among patients with ventricular tachyarrhythmias. In contrast, risk of the composite arrhythmic endpoint and risk of cardiac rehospitalization were not affected by BB dose.
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Desfibriladores Implantáveis , Taquicardia Ventricular , Antagonistas Adrenérgicos beta/uso terapêutico , Desfibriladores Implantáveis/efeitos adversos , Humanos , Prognóstico , Recidiva , Estudos Retrospectivos , Fatores de Risco , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/tratamento farmacológico , Taquicardia Ventricular/etiologia , Fibrilação Ventricular/diagnóstico , Fibrilação Ventricular/tratamento farmacológicoRESUMO
INTRODUCTION: The study sought to assess the effect of treatment with mineralocorticoid receptor antagonists (MRAs) on long-term prognosis of patients with systolic heart failure (HF) surviving index episodes of ventricular tachyarrhythmias. METHODS: A large retrospective registry was used including consecutive HF patients with left ventricular ejection fraction <45% and index episodes of ventricular tachyarrhythmias from 2002 to 2015. The primary endpoint was all-cause mortality at 3 years and secondary endpoints were rehospitalization, as well as the composite endpoint consisting of recurrent ventricular tachyarrhythmias, sudden cardiac death and appropriate implantabe cardioverter defibrillator (ICD) therapies at 3 years. RESULTS: 748 patients were included, 20% treated with MRA and 80% without. At 3 years, treatment with MRA was not associated with improved all-cause mortality (22% vs. 24%, log-rank p = 0.968; hazard ratio (HR) = 1.008; 95% CI 0.690-1.472; p = 0.968). Accordingly, risk of the composite endpoint (28% vs. 27%; HR = 1.131; 95% CI 0.806-1.589; p = 0.476) and first cardiac rehospitalization (24% vs. 22%; HR = 1.139; 95% CI 0.788-1.648; p = 0.489) were not affected by treatment with MRA. CONCLUSION: In patients with ventricular tachyarrhythmias, treatment with MRA was not associated with improved all-cause mortality at 3 years. The therapeutic effect of MRA treatment in patients with ventricular tachyarrhythmias needs to be reinvestigated within further randomized controlled trials.
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Antagonistas de Receptores de Mineralocorticoides/farmacologia , Antagonistas de Receptores de Mineralocorticoides/uso terapêutico , Taquicardia Ventricular/tratamento farmacológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Eplerenona/farmacologia , Eplerenona/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Sistema de Registros , Estudos Retrospectivos , Espironolactona/farmacologia , Espironolactona/uso terapêutico , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/mortalidade , Adulto JovemRESUMO
PURPOSE: To explore doses from common adult computed tomography (CT) examinations and propose national diagnostic reference levels (nDRLs) for Nigeria. MATERIALS AND METHODS: This retrospective study was approved by the Nnamdi Azikiwe University and University Teaching Hospital Institutional Review Boards (IRB: NAUTH/CS/66/Vol8/84) and involved dose surveys of adult CT examinations across the six geographical regions of Nigeria and Abuja from January 2016 to August 2017. Dose data of adult head, chest and abdomen/pelvis CT examinations were extracted from patient folders. The median, 75th and 25th percentile CT dose index volume (CTDIvol) and dose-length-product (DLP) were computed for each of these procedures. Effective doses (E) for these examinations were estimated using the k conversion factor as described in the ICRP publication 103 (EDLP = k × DLP). RESULTS: The proposed 75th percentile CTDIvol for head, chest, and abdomen/pelvis are 61 mGy, 17 mGy, and 20 mGy, respectively. The corresponding DLPs are 1310 mGy.cm, 735 mGy.cm, and 1486 mGy.cm respectively. The effective doses were 2.75 mSv (head), 10.29 mSv (chest), and 22.29 mSv (abdomen/pelvis). CONCLUSION: Findings demonstrate wide dose variations within and across centres in Nigeria. The results also show CTDIvol comparable to international standards, but considerably higher DLP and effective doses.
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Doses de Radiação , Tomografia Computadorizada por Raios X/normas , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Pesquisas sobre Atenção à Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Nigéria , Valores de Referência , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos , Adulto JovemRESUMO
The tumor suppressor P53 is a critical regulator of normal cellular homeostasis whose function is either distorted or lost in several cancer types including colorectal cancer (CRC). A small group of microRNAs have come to be recognized as essential mediators of P53 function. In a genome-wide systematic approach, we explored miRNAs that are substantially altered by P53 loss and found miR-30e to be the most significantly deregulated miRNA in P53-knockout human CRC cells. We identified miR-30e-5p to be a novel direct transcriptional target of P53 with gain and loss of function experiments revealing miR-30e-5p to be a significant regulator of tumor cell migration, invasion and in vivo metastasis mediated in part by integrins alpha-6 and beta-1 as novel targets. MiR-30e-5p also significantly reduced tumor cell proliferation by causing G1/S cell cycle arrest, which was achieved by inducing P21 and P27 expression. Finally, we found miR-30e-5p to be lost in resected CRC tumors as compared to normal colon tissues. Taken together, miR-30e-5p is a novel effector of P53-induced suppression of migration, invasion and metastasis.
Assuntos
Neoplasias Colorretais/genética , Integrina alfa6/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas de Membrana/genética , MicroRNAs/genética , Proteína Supressora de Tumor p53/genética , Proteínas Adaptadoras de Transdução de Sinal , Animais , Pontos de Checagem do Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Neoplasias Colorretais/patologia , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p27/genética , Regulação Neoplásica da Expressão Gênica , Células HCT116 , Humanos , Camundongos , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Metástase Neoplásica , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
MicroRNAs now not only represent a significant mechanism for post-transcriptional gene regulation, but have come to be appreciated as molecules with far reaching tentacles affecting diverse processes and pathologies by modulating amongst others, cellular gene expression, epigentic mechanisms, complex signaling cascades, cell-cell communication, the immune system and microenvironmental interactions between several cell types, tissues and organ systems. In this review, we systematically reflect on the impact of miRNAs on all types of benign and malignant human stem cells, looking at the roles they play in maintaining or changing the stem cell state, and review how aberrations of their expression and function within diverse types of stem cells orchestrate carcinogenesis and metastasis. As a conclusion, we consider it striking to see how similar some miR-driven mechanisms are between different types of stem cells and cancer cells, and how this might support hypotheses of miR-driven embryologic pathway reactivation in metastasis or propose putative functions of miRs in important novel cross-topic fields such as obesity and cancer.
Assuntos
Regulação da Expressão Gênica , MicroRNAs/genética , Células-Tronco Neoplásicas/metabolismo , Células-Tronco/metabolismo , Animais , Diferenciação Celular/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Metástase Neoplásica , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Células-Tronco Neoplásicas/patologia , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/metabolismo , Células-Tronco/citologia , Microambiente Tumoral/genéticaRESUMO
Two molecular beacons were designed as complementary fluorescent imaging probes for miRNA-21 and miRNA-31. Both beacons were prepared by a combination of solid-phase protocol and Cu(i)-catalyzed cycloaddition chemistry. The four photostable and bright fluorophores were attached to 2'-positions in the stem part of the two beacons. One beacon was labeled by a green-to-red emitting and the other by a blue-to-yellow emitting energy transfer pair. This two by two combination yields the four color emission readout. In vitro experiments demonstrate rapid and highly selective opening of both molecular beacons upon addition of the complementary target RNA and excellent green : red and blue : yellow emission color contrasts. Confocal microscopy of selected cancer cell lines provides evidence that a four color imaging of versicular miRNA-21 and miRNA-31 can be achieved both selectively and simultaneously upon transfection by the beacons, and that the fluorescent readouts track well with miRNA levels determined by PCR.
Assuntos
MicroRNAs/metabolismo , Sondas de Oligonucleotídeos/metabolismo , Imagem Óptica/métodos , Linhagem Celular Tumoral , Sobrevivência Celular , Humanos , Espaço Intracelular/metabolismo , Sondas de Oligonucleotídeos/química , Fatores de TempoRESUMO
Cancer is an exceedingly complex disease that is orchestrated and driven by a combination of multiple aberrantly regulated processes. The nature and depth of involvement of individual events vary between cancer types, and in lung cancer, the deregulation of the epigenetic machinery, the tumor microenvironment and the immune system appear to be especially relevant. The contribution of microRNAs to carcinogenesis and cancer progression is well established with many reports and investigations describing the involvement of microRNAs in lung cancer, however most of these studies have concentrated on single microRNA-target relations and have not adequately addressed the complexity of their interactions. In this review, we focus, in part, on the role of microRNAs in the epigenetic regulation of lung cancer where they act as active molecules modulating enzymes that take part in methylation-mediated silencing and chromatin remodeling. Additionally, we highlight their contribution in controlling and modulating the tumor microenvironment and finally, we describe their role in the critical alteration of essential molecules that influence the immune system in lung cancer development and progression.
Assuntos
Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/imunologia , MicroRNAs/genética , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia , Animais , Humanos , Imunomodulação , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologiaRESUMO
The FUS-CHOP fusion protein has been found to be instrumental for specific oncogenic processes in liposarcoma, but its ability to induce metastasis and the underlying mechanisms by which this can be achieved remain unknown. To dissect its functional role in this context, we stably overexpressed this protein in SW872 liposarcoma and HT1080 fibrosarcoma cell lines, and were able to demonstrate that forced expression of FUS-CHOP significantly increases migration and invasion, as well as enhances lung and liver metastasis in the in vivo chicken chorioallantoic membrane (CAM) model, that is proliferation independent. Additionally, FUS-CHOP enhances the expression of matrix-metalloproteinases -2 and -9, and transactivates their promoters in vitro. Mutational analysis showed that C/EBP-ß- (-769/-755), NF-κB (-525/-516) and CREB/AP-1 (-218/-207) sites were important for MMP-2 and NF-κB (-604/-598), AP-1 (-539/-532) and AP-1 (-81/-72) for MMP-9 transactivation. Moreover, a direct in vivo interaction of FUS-CHOP was observed in case of the MMP-2 promoter within region (-769/-207). siRNA data revealed that MMP-2 expression is essential in the FUS-CHOP induced metastatic phenotype. MMP-2-mRNA and protein expression correlated significantly with FUS-CHOP positivity in 46 resected patient liposarcoma tissues. We have for the first time provided substantial evidence for the FUS-CHOP oncoprotein as an inducer of metastasis that is due to the transcriptional induction of specific tumor-associated proteases. Insights gained from this study not only support a deeper understanding of the mechanistic properties of FUS-CHOP, but also open up new avenues for targeted therapy.
Assuntos
Lipossarcoma/patologia , Metaloproteinase 2 da Matriz/biossíntese , Metaloproteinase 9 da Matriz/biossíntese , Proteínas de Fusão Oncogênica/metabolismo , Proteína FUS de Ligação a RNA/metabolismo , Fator de Transcrição CHOP/metabolismo , Células 3T3 , Idoso , Animais , Proteína beta Intensificadora de Ligação a CCAAT/genética , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Galinhas , Membrana Corioalantoide/citologia , Membrana Corioalantoide/patologia , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Células HEK293 , Humanos , Lipossarcoma/genética , Lipossarcoma/metabolismo , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 9 da Matriz/genética , Camundongos , Pessoa de Meia-Idade , NF-kappa B/genética , Invasividade Neoplásica , Metástase Neoplásica , Proteínas de Fusão Oncogênica/biossíntese , Proteínas de Fusão Oncogênica/genética , Regiões Promotoras Genéticas/genética , Interferência de RNA , RNA Interferente Pequeno , Proteína FUS de Ligação a RNA/biossíntese , Proteína FUS de Ligação a RNA/genética , Fator de Transcrição AP-1/genética , Fator de Transcrição CHOP/biossíntese , Fator de Transcrição CHOP/genéticaRESUMO
Myelodysplastic neoplasms (MDS) are a heterogenous group of clonal stem cell disorders characterized by dysplasia and cytopenia in one or more cell lineages. Anemia is a very common symptom that is often treated with blood transfusions and/or erythropoiesis stimulating factors. Iron overload results from a combination of these factors together with the disease-associated ineffective erythropoiesis, that is seen especially in MDS cases with SF3B1 mutations. A growing body of research has shown that erythroferrone is an important regulator of hepcidin, the master regulator of systemic iron homeostasis. Consequently, it is of interest to understand how this molecule contributes to regulating the iron balance in MDS patients. This short review evaluates our current understanding of erythroferrone in general, but more specifically in MDS and seeks to place in context how the current knowledge could be utilized for prognostication and therapy.
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The paucity of microbiome studies at intestinal tissues has contributed to a yet limited understanding of potential viral and bacterial cofactors of colorectal cancer (CRC) carcinogenesis or progression. We analysed whole-genome sequences of CRC primary tumours, their corresponding metastases and matched normal tissue for sequences of viral, phage and bacterial species. Bacteriome analysis showed Fusobacterium nucleatum, Streptococcus sanguinis, F. Hwasookii, Anaerococcus mediterraneensis and further species enriched in primary CRCs. The primary CRC of one patient was enriched for F. alocis, S. anginosus, Parvimonas micra and Gemella sp. 948. Enrichment of Escherichia coli strains IAI1, SE11, K-12 and M8 was observed in metastases together with coliphages enterobacteria phage φ80 and Escherichia phage VT2φ_272. Virome analysis showed that phages were the most preponderant viral species (46%), the main families being Myoviridae, Siphoviridae and Podoviridae. Primary CRCs were enriched for bacteriophages, showing five phages (Enterobacteria, Bacillus, Proteus, Streptococcus phages) together with their pathogenic hosts in contrast to normal tissues. The most frequently detected, and Blast-confirmed, viruses included human endogenous retrovirus K113, human herpesviruses 7 and 6B, Megavirus chilensis, cytomegalovirus (CMV) and Epstein-Barr virus (EBV), with one patient showing EBV enrichment in primary tumour and metastases. EBV was PCR-validated in 80 pairs of CRC primary tumour and their corresponding normal tissues; in 21 of these pairs (26.3%), it was detectable in primary tumours only. The number of viral species was increased and bacterial species decreased in CRCs compared with normal tissues, and we could discriminate primary CRCs from metastases and normal tissues by applying the Hutcheson t-test on the Shannon indices based on viral and bacterial species. Taken together, our results descriptively support hypotheses on microorganisms as potential (co)risk factors of CRC and extend putative suggestions on critical microbiome species in CRC metastasis.
Assuntos
Neoplasias Colorretais , Infecções por Vírus Epstein-Barr , Microbiota , Neoplasias Colorretais/genética , Herpesvirus Humano 4 , Humanos , Fatores de RiscoRESUMO
MiRs are important players in cancer and primarily genetic/transcriptional means of regulating their gene expression are known. However, epigenetic changes modify gene expression significantly. Here, we evaluated genome-wide methylation changes focusing on miR genes from primary CRC and corresponding normal tissues. Differentially methylated CpGs spanning CpG islands, open seas, and north and south shore regions were evaluated, with the largest number of changes observed within open seas and islands. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis revealed several of these miRs to act in important cancer-related pathways, including phosphatidylinositol 3-kinase (PI3K)-protein kinase B (Akt) and mitogen-activated protein kinase (MAPK) pathways. We found 18 miR genes to be significantly differentially methylated, with MIR124-2, MIR124-3, MIR129-2, MIR137, MIR34B, MIR34C, MIR548G, MIR762, and MIR9-3 hypermethylated and MIR1204, MIR17, MIR17HG, MIR18A, MIR19A, MIR19B1, MIR20A, MIR548F5, and MIR548I4 hypomethylated in CRC tumor compared with normal tissue, most of these miRs having been shown to regulate steps of metastasis. Generally, methylation changes were distributed evenly across all chromosomes with predominance for chromosomes 1/2 and protein-coding genes. Interestingly, chromosomes abundantly affected by methylation changes globally were rarely affected by methylation changes within miR genes. Our findings support additional mechanisms of methylation changes affecting (miR) genes that orchestrate CRC progression and metastasis.
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High proportion of copper has become a global challenge owing to its negative impact on the environment and public health complications. The present study focuses on the fabrication of a polyvinylidene fluoride (PVDF)-polyvinyl pyrrolidone (PVP) fiber membrane incorporated with varying loading (0, 0.5, 1.0, 1.5, and 2.0 wt%) of titanium dioxide (TiO2) nanoparticles via phase inversion technique to achieve hydrophilicity along with high selectivity for copper removal. The developed fibers were characterized based on scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), permeability, porosity, zeta potential, and contact angle. The improved membrane (with 1.0 wt% TiO2) concentration recorded the maximum flux (223 L/m2·h) and copper rejection (98.18%). Similarly, 1.0 wt% concentration of TiO2 nanoparticles made the membrane matrix more hydrophilic with the least contact angle of 50.01°. The maximum copper adsorption capacity of 69.68 mg/g was attained at 1.0 wt% TiO2 concentration. The experimental data of adsorption capacity were best fitted to the Freundlich isotherm model with R2 value of 0.99573. The hybrid membrane developed in this study has considerably eliminated copper from leachate and the concentration of copper in the permeate was substantially reduced to 0.044 mg/L, which is below standard discharge threshold.
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The present study synthesized nano-magnetite (Fe3O4) from milled steel chips using the high energy ball milling (HEBM) method, characterized it, and then utilized it as a sorbent to remediate boron concentration at various pH (4-9), dosages (0.1-0.5 g), contact times (20-240 min), and initial concentrations (10-100 mg/L). The nano-sorbents were characterized based on SEM structure, elemental composition (EDX), surface area analysis (BET), crystallinity (XRD), and functional group analysis (FTIR). The highest adsorption capacity of 8.44 mg/g with removal efficiency of 84% was attained at pH 8, 0.5 g dosage, contact time of 180 min, and 50 mg/L initial concentration. The experimental data fit best with the pseudo-second-order kinetic model with R2 of 0.998, while the Freundlich adsorption isotherm describes the adsorption process with an R2 value of 0.9464. A regeneration efficiency of 47% was attained even after five cycles of reusability studies. This efficiency implies that the nano-magnetite has the potential for sustainable industrial application.
Assuntos
Poluentes Químicos da Água , Purificação da Água , Adsorção , Boro , Óxido Ferroso-Férrico , Concentração de Íons de Hidrogênio , Cinética , Poluentes Químicos da Água/análiseRESUMO
Over the years, the persistent occurrence of superfluous endocrine-disrupting compounds (EDCs) (sub µg L-1) in water has led to serious health disorders in human and aquatic lives, as well as undermined the water quality. At present, there are no generally accepted regulatory discharge limits for the EDCs to avert their possible negative impacts. Moreover, the conventional treatment processes have reportedly failed to remove the persistent EDC pollutants, and this has led researchers to develop alternative treatment methods. Comprehensive information on the recent advances in the existing novel treatment processes and their peculiar limitations is still lacking. In this regard, the various treatment methods for the removal of EDCs are critically studied and reported in this paper. Initially, the occurrences of the EDCs and their attributed effects on humans, aquatic life, and wildlife are systematically reviewed, as well as the applied treatments. The most noticeable advances in the treatment methods include adsorption, catalytic degradation, ozonation, membrane separation, and advanced oxidation processes (AOP), as well as hybrid processes. The recent advances in the treatment technologies available for the elimination of EDCs from various water resources alongside with their associated drawbacks are discussed critically. Besides, the application of hybrid adsorption-membrane treatment using several novel nano-precursors is carefully reviewed. The operating factors influencing the EDCs' remediations via adsorption is also briefly examined. Interestingly, research findings have indicated that some of the contemporary techniques could achieve more than 99% EDCs removal.
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The continuous increase in anthropogenic activities resulting in an increase in boron concentration in the environment is becoming a serious threat to public health and the ecosystem. In this regard, a hybrid polyvinylidene fluoride (PVDF)-polyvinyl pyrrolidone (PVP) hollow fiber was synthesized with hydrophilic nano-titanium oxide (TiO2) at varied loadings of 0, 0.5, 1.0, 1.5, and 2.0 wt% using the phase inversion technique. The resultant membranes were characterized in terms of Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDX), contact angle, porosity, and zeta potential. The permeability flux was assessed using both pure water and leachate; also, rejection performance was evaluated based on boron removal from the leachate. The results revealed that the membrane with 1.0 wt% loading had the highest flux alongside an upturn in boron rejection percentage of 223 L/m2·h and 94.39%, respectively. In addition, the lowest contact angle of 50.01° was recorded with 1.0 wt% TiO2 loading, and this implies that it is the most hydrophilic. Throughout the experiment cycles, the fiber with 1.0 wt% TiO2 loading demonstrated a high flux recovery varying between 92.82% and 76.26% after 9 h filtration time. The physicochemical analysis of the permeate revealed that the boron concentration was significantly reduced to 0.43 mg/L, which is far lower than the discharge limit of 1.0 mg/L.
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Metastases's spreading is the main cause of mortality for advanced stage cancer patients, including melanoma. The formation of metastases is favored by enhanced migratory and invasive capacities of tumor cells. Tumor suppressor gene NF1 is a negative regulator of RAS and its deregulation plays an important role in several aspects of melanoma transformation and progression. However, very little is described about the role of NF1 in cellular migration and invasion. In this study, our results show on the one hand, that the loss of NF1 expression delays migration of human melanoblasts via a RAC1-dependent mechanism. On the other hand, our data indicate that NF1 loss in melanoma cells is enhancing migration, intravasation and metastases formation in vivo. Moreover, not only this phenotype is associated with an upregulation of PREX1 but also patient-derived melanoma samples with low NF1 expression present increased levels of PREX1. In sum, our study brings new elements on the mechanism controlling cellular migration in the context of NF1 loss. These data are of prime interest to improve treatment strategies against all NF1-mutated tumors, including this subtype of melanoma.