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The disturbance of ecological stability may take place in tropical regions due to the elevated biomass density resulting from heavy metal and other contaminant pollution. In this study, 62 valid soil samples were collected from Sanya. Source analysis of heavy metals in the area was carried out using absolute principal component-multiple linear regression receptor modelling (APCS-MLR); the comprehensive ecological risk of the study area was assessed based on pollution sources; the Monte-Carlo model was used to accurately predict the health risk of pollution sources in the study area. The results showed that: The average contents of soil heavy metals Cu, Ni and Cd in Sanya were 5.53, 6.56 and 11.66 times higher than the background values of heavy metals. The results of soil geo-accumulation index (Igeo) showed that Cr, Mo, Mn and Zn were unpolluted to moderately polluted, Cu and Ni were moderately polluted, and Cd was moderately polluted to strongly polluted. The main sources of heavy metal pollution were natural sources (57.99%), agricultural sources (38.44%) and traffic sources (3.57%). Natural and agricultural sources were jointly identified as priority control pollution sources and Cd was the priority control pollution element for soil ecological risk. Heavy metal content in Sanya did not pose a non-carcinogenic risk to the population, but there was a carcinogenic risk to children. The element Zn had a high carcinogenic risk to children, and was a priority controlling pollutant element for the risk of human health, with agricultural sources as the priority controlling pollutant source.
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Metales Pesados , Método de Montecarlo , Contaminantes del Suelo , Metales Pesados/análisis , Contaminantes del Suelo/análisis , China , Medición de Riesgo , Humanos , Monitoreo del Ambiente/métodos , Clima Tropical , Niño , Suelo/químicaRESUMEN
By introducing the parameters of radon exhalation rate and radon diffusion coefficient, the distribution of radon concentration field on ramp under the condition of superposition of temperature field and flow field is simulated. The simulation results show that the distribution of radon concentration in the ramp under the condition of low-speed ventilation is greatly affected by the temperature field and flow field, and the change of radon exhalation caused by temperature is the main factor leading to the change of radon concentration in the ramp. The change of temperature will cause the overall increase of radon concentration in the ramp. Under the condition of constant flow field, the radon concentration in the chamber is more than two times higher than the average radon concentration in the ramp. Some areas severely exceeded the limit.
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Contaminantes Radiactivos del Aire , Monitoreo de Radiación , Radón , Radón/análisis , Temperatura , Viento , Monitoreo de Radiación/métodos , Contaminantes Radiactivos del Aire/análisisRESUMEN
Atrial fibrillation (AF) is a prevalent arrhythmia that requires effective biomarkers and therapeutic targets for clinical management. In recent years, non-coding RNAs (ncRNAs) have emerged as key players in the pathogenesis of AF, particularly through the ceRNA (competitive endogenous RNA) mechanism. By acting as ceRNAs, ncRNAs can competitively bind to miRNAs and modulate the expression of target mRNAs, thereby influencing the biological behavior of AF. The ceRNA axis has shown promise as a diagnostic and prognostic biomarker for AF. This review provides a comprehensive overview of the roles of ncRNAs in the development and progression of AF, highlighting the intricate crosstalk between different ncRNAs in AF pathophysiology. Furthermore, we discuss the potential implications of targeting the circRNA/lncRNA-miRNA-mRNA axis for the diagnosis, prognosis, and therapeutic intervention of AF.
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Fibrilación Atrial , MicroARNs , ARN Largo no Codificante , Humanos , MicroARNs/genética , ARN Mensajero/genética , ARN Largo no Codificante/genética , ARN Circular/genética , Fibrilación Atrial/genética , Redes Reguladoras de Genes , ARN no TraducidoRESUMEN
BACKGROUND: Previous studies have traditionally attributed the initiation of cancer cells to genetic mutations, considering them as the fundamental drivers of carcinogenesis. However, recent research has shed light on the crucial role of epigenomic alterations in various cell types present within the tumor microenvironment, suggesting their potential contribution to tumor formation and progression. Despite these significant findings, the progress in understanding the epigenetic mechanisms regulating tumor heterogeneity has been impeded over the past few years due to the lack of appropriate technical tools and methodologies. RESULTS: The emergence of single-cell sequencing has enhanced our understanding of the epigenetic mechanisms governing tumor heterogeneity by revealing the distinct epigenetic layers of individual cells (chromatin accessibility, DNA/RNA methylation, histone modifications, nucleosome localization) and the diverse omics (transcriptomics, genomics, multi-omics) at the single-cell level. These technologies provide us with new insights into the molecular basis of intratumoral heterogeneity and help uncover key molecular events and driving mechanisms in tumor development. CONCLUSION: This paper provides a comprehensive review of the emerging analytical and experimental approaches of single-cell sequencing in various omics, focusing specifically on epigenomics. These approaches have the potential to capture and integrate multiple dimensions of individual cancer cells, thereby revealing tumor heterogeneity and epigenetic features. Additionally, this paper outlines the future trends of these technologies and their current technical limitations.
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Epigenómica , Neoplasias , Humanos , Epigenómica/métodos , Metilación de ADN , Epigénesis Genética , Cromatina , Neoplasias/genética , Microambiente TumoralRESUMEN
The release of nitrogen and phosphorus from sediments into lake water will exacerbate the eutrophication of lakes and endanger ecological safety and human health. Microorganisms are indispensable in nitrogen and phosphorus conversion, and accurate analysis of the distribution characteristics and sources of nitrogen and phosphorus in sediments as well as their relationship with microorganisms is an important prerequisite for lake eutrophication control. Taking Taihu Lake as the study area, 30 surface sediment samples were collected, and the grain size, pH, organic matter (OM), dissolved organic carbon (DOC), total phosphorus (TP), total nitrogen (TN), nitrate nitrogen (NO3--N), and dissolved organic nitrogen (DON) along with some other index contents were measured and analyzed; accordingly, spatial distribution characteristics were analyzed. While using nutrient agar (NA), the number of aerobic bacteria (AB) was determined by plate counting in the medium. Combined with principal component analysis (PCA) and Pearson correlation analysis, the spatial distribution characteristics and sources of sediments and AB in Taihu Lake were explored. The characteristics of sediment pollution in Taihu Lake were studied using the comprehensive pollution index and the organic pollution index methods. The results revealed that the average sediment indicators of the surface layer of Taihu Lake were as follows:AB was 9.25×104 CFU·g-1, average particle size (MZ) was 17.59 µm, pH was 7.62, ω(OM) was 15.05 g·kg-1, ω(DOC) was 71.60 mg·kg-1, ω(TP) was 598.13 mg·kg-1, ω(TN) was 1113.92 mg·kg-1, ω(NO3--N) was 3.22 mg·kg-1, and ω(DON) was 22.60 mg·kg-1. The comprehensive pollution index (FF) showed that 13% of the Taihu Lake was moderately polluted, while 87% was heavily polluted. Excluding the area in the center of the lake, the southern lake area, and some lakes in the western part of the East Taihu Lake, TN in the rest of the area was moderately and severely polluted. In addition to the heavy pollution of Zhushan Bay, the TP in Taihu Lake was generally at light and moderate pollution. The organic pollution index (OI) showed that the organic pollution of the sediments of Taihu Lake was relatively light, majorly caused by organic nitrogen (ON) pollution. DOC, DON, TN, and OM in Taihu Lake were primarily derived from the influence of aquatic plants, and TP And AB were primarily derived from the influence of the external input of rivers. This research will provide theoretical support for lake eutrophication treatment and also provide new ideas for further analysis of AB to remove nitrogen and phosphorus pollution from sediments.
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Bacterias Aerobias , Contaminantes Químicos del Agua , Humanos , Monitoreo del Ambiente , Contaminantes Químicos del Agua/análisis , Nitrógeno/análisis , Fósforo/análisis , Lagos/química , Eutrofización , Materia Orgánica Disuelta , China , Sedimentos Geológicos/químicaRESUMEN
With the strengthened awareness of environmental protection and the growing interests of wastes recycling, silicon recovery from polycrystalline silicon kerf loss (PSKL) has drawn extensive attentions all over the world. In this paper, an efficient and environmental friendly approach for oxygen removal and silicon recovery from PSKL by combining vacuum magnesium thermal reduction (VMTR) and hydrochloric acid leaching was proposed. The effects of temperature, duration and particle size on the reduction of PSKL were investigated thoroughly. It is proved that the amorphous SiO2 in PSKL can be reduced by magnesium vapor at 923 K to generate MgO, and then the produced MgO can be dissolved by hydrochloric acid to eliminate the impurity oxygen. The oxygen removal fraction and the silicon recovery efficiency attained 98.43% and 94.46%, respectively, under the optimal conditions, indicating that a high efficiency recovery of silicon from PSKL was achieved. Compared to the existing PSKL deoxidation technologies, e.g., the high temperature process and the hydrofluoric acid leaching method, this method requires a relatively lower temperature and the waste acid can be easily recovered. Additionally, by taking into accounts the fact that the MgCl2 in leaching liquor can be recycled for cyclic utilization with a molten salt electrolysis method, it should be suggested that an efficient and environmental friendly process for PSKL recycling was obtained, which shows good prospects for commercial application.
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Magnesio , Silicio , Silicio/química , Magnesio/química , Dióxido de Silicio , Ácido Clorhídrico , Óxido de Magnesio , Vacio , Reciclaje/métodosRESUMEN
BACKGROUND: The specific pathogenesis of atrial fibrillation (AF) remains unclear. In this study, we examined the expression of differential messenger RNAs (mRNAs), circular RNAs (circRNAs), and long-stranded noncoding RNAs (lncRNAs) from human peripheral blood mononuclear cells to initially construct a circRNA/lncRNA-miRNA-mRNA ceRNA regulatory network to explore the pathogenesis of AF and to screen for potential biomarkers. METHODS: A total of four pairs of AF cases and healthy subjects were selected to detect differentially expressed mRNAs, circRNAs, and lncRNAs in peripheral blood mononuclear cells by microarray analysis. And 20 pairs of peripheral blood from AF patients and healthy subjects were selected for validation of mRNA, circRNA, and lncRNA by quantitative real-time PCR (qRT-PCR).The relevant ceRNA networks were constructed by GO and KEGG and correlation analysis. RESULTS: The results showed that compared with healthy subjects, there were 813 differentially expressed mRNAs (DEmRNAs) in peripheral blood monocytes of AF, including 445 upregulated genes and 368 downregulated genes, 120 differentially expressed circRNAs (DEcircRNAs), including 65 upregulated and 55 downregulated, 912 differentially expressed lncRNAs (DElncRNAs), including 531 upregulated and 381 downregulated lncRNAs. GO and KEGG analysis of DERNA revealed the biological processes and pathways involved in AF. Based on microarray data and predicted miRNAs, a ceRNA network containing 34 mRNAs, 212 circRNAs, 108 lncRNAs, and 38 miRNAs was constructed. CONCLUSION: We revealed a novel ceRNA network in AF and showed that downregulated XIST, circRNA_2773, and CADM1 were negatively correlated with miR-486-5p expression and had a potential targeting relationship with miR-486-5p.
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Fibrilación Atrial , MicroARNs , ARN Largo no Codificante , Humanos , MicroARNs/genética , ARN Circular/genética , ARN Mensajero/genética , ARN Largo no Codificante/genética , Leucocitos Mononucleares/metabolismo , Redes Reguladoras de Genes , Biomarcadores , Molécula 1 de Adhesión Celular/genéticaRESUMEN
The geographical location of West Taihu Lake determines that it is the entrance of the whole Taihu Lake, and the intensive industries around it pose a great threat to the ecology of Taihu Lake. We innovatively combined Pb isotope ratio analysis with ecological risk assessment index to quantify the source-oriented ecological risk of heavy metals (HMs) in the sediments of West Taihu Lake. In this study, the representative HMs Zn, Pb, Cr, and Cd in the surface (0-2 cm) sediments of West Tai Lake were determined, and the ecological risk assessment of HM sources was carried out based on the Pb isotope ratio and ecological risk index. The results showed that HMs were significantly enriched in the south and the west of the study area. The average geo-accumulation index (Igeo) of Pb was unpolluted, Cr and Zn were between unpolluted and moderately polluted, and Cd was moderately polluted. The average ecological risk index (Ei) of Pb, Cr, and Zn was low, and only Cd reached a considerable risk (ECd = 120.7), which accounted for 89.8% of the comprehensive ecological risk index (RI). However, the RI in the whole study area (RI = 134.4) still indicated low risk. There was a significant correlation between Pb and other HMs (P < 0.05). The IsoSource analysis showed that the order of contribution rate was fossil fuels (48.0%) > industrial sources (35.8%) > natural sources (14.9%) > agricultural sources (1.3%). The HM pollution caused by fossil fuel combustion and industrial activities reaches a moderate ecological risk, whereas natural sources and agricultural sources pose a low risk. Overall, the main sources of HM pollution are anthropogenic, which pose moderate ecological risk to the study area and should be paid more attention to.
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Metales Pesados , Contaminantes Químicos del Agua , Lagos , Cadmio , Plomo , Sedimentos Geológicos , Monitoreo del Ambiente , Contaminantes Químicos del Agua/análisis , Metales Pesados/análisis , Medición de Riesgo , ChinaRESUMEN
Herein, the preparation of the key triazone-triazole intermediate of ensitrelvir (S-217622) via sequential cyclization and alkylation reaction is described. Firstly, chloromethyl triazole was synthesized through a one-pot tandem process (condensation and cyclization reaction) from commercially available chloroacetamide in a 72% yield. Then, the key triazone-triazole intermediate was obtained in a second one-pot process by N-alkylation with triazone followed by highly selective N 1-methylation with iodomethane in a 54% yield. In addition, two of the main process impurities were synthesized and identified. This novel alternative two-stage one-pot strategy for synthesizing the key triazone-triazole intermediate opens a new avenue for further research and development of ensitrelvir analogs.
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With the rapid economic development, potentially toxic elements (PTEs) are continuously migrating, transforming, and enriching in farmland through atmospheric deposition and other media, posing threats to food security and human health. At present, there are few quantitative studies on the health risks of PTEs sources in farmland. In this study, absolute principal component score-multiple linear regression (APCS-MLR) receptor model was used to quantify the pollution sources of PTEs in farmland in Suzhou of Yangtze River Delta Economic Zone, China. Combined with geoaccumulation index (Igeo) and health risk assessment model, the source risk of PTEs was further quantified. The results show that Cd has reached the level of unpolluted to moderate polluted (0 < Igeo < 1); the total hazard index (THI) and total carcinogenic risk (TCR) index of PTEs are acceptable for adults, but not for children (THI > 1, TCR > 1 × 10-4). The results of APCS-MLR source apportionment were industrial sources (25.65%), agricultural sources (20.00%), traffic sources (16.81%), and domestic pollution sources (9.71%). The Igeo values of all pollution sources were less than 0, and no ecological risk was caused. The contribution patterns of pollution sources to THI and TCR in adults and children are similar. Industrial pollution sources pose the greatest non-carcinogenic risk to humans, accounting for 47.35% and 47.26% of adults and children, respectively; for carcinogenic risks, domestic pollution sources contribute the most among all identified pollution sources, accounting for 27.71% and 27.73% of adults and children, respectively. In general, this study emphasizes the need to strengthen the supervision of industrial pollution sources and domestic pollution sources in the study area to reduce the health risks to children.
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Carcinógenos , Metales Pesados , Contaminantes del Suelo , Adulto , Carcinógenos/análisis , Niño , China , Monitoreo del Ambiente/métodos , Granjas , Humanos , Metales Pesados/análisis , Medición de Riesgo , Suelo , Contaminantes del Suelo/análisisRESUMEN
As an abundantly present tobacco component, carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) has also been detected in atmospheric particulate matter, suggesting the ineluctable exposure risk of this contaminant. NNK metabolic activation by cytochrome P450 enzymes (CYPs) is a prerequisite to exerting its genotoxicity, but the metabolic regioselectivity and mechanism are still unknown. Here the binding feature and regioselectivity of CYPs 1A1, 1A2, 2A6, 2A13, 2B6, and 3A4 toward NNK are unraveled through molecular docking and molecular dynamics (MD) simulations. Binding mode analyses reveal that 1A2 and 2B6 have definite preferences for NNK α-methyl hydroxylation, while the other four CYPs preferentially catalyze α-methylene hydroxylation. The binding affinities between NNK and CYPs evaluated by the binding free energies follow the order 2A13 > 2B6 > 1A2 > 2A6 > 1A1 > 3A4. Density functional theory (DFT) calculations are further performed to characterize the mechanism of NNK biotransformation. Results show that the α-hydroxyNNK generated from α-hydroxylation may undergo nonenzymatic decomposition to form genotoxic diazohydroxide and aldehyde, and further oxidation by P450 to yield nitrosamide, which mainly contributes to NNK toxification capacity. Meanwhile the pyridine N-oxidation and denitrosation of Cα-radical intermediate play an important role in detoxifying NNK. Overall, the present study provides the molecular basis for CYP-catalyzed regioselectivity and mechanism of NNK biotransformation, which can enable the identification of metabolites for assessing the health risk of individual NNK exposure.