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1.
Environ Res ; 251(Pt 2): 118735, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38518905

RESUMO

Inert construction and demolition waste from Hong Kong (HK public fills) has been used for marine trial reclamation in the Guanghai Bay (GHWT) of the Chinese Mainland. However, an environmental assessment of HK public fills is necessary due to higher radioactivity in HK soils than typical global levels. Here, radiation dose rate, gamma radionuclides and gross beta of HK public fills were analyzed. The origin information was explored using natural primordial radionuclides as fingerprints. Our data show that radiation dose rate of HK public fills before disposal was 0.14-0.54 (0.33 ± 0.03) µSv/h (n = 16,722 data with 2787 ships) in 2014, which is less than the GHWT background. Monthly detection of 238U, 226Ra, 210Pb, 232Th, 228Th, 40K, and gross beta in HK public fills was conducted on three random ships. Their specific activities were <6.27-155.5, 58.7-98.7, <7.83-238.2,97.9-168.6, 87.1-136.0, 463.1-1,018, and 1047-1658 Bq/kgDW, respectively. These results suggest that the radioactivity levels of HK public fills are essentially the same as the GHWT background. The study assessed potential risks using various indices icluding Raeq (Radium equivalent activity), Hex (External radiation hazard index), Hin (Internal radiation hazard index), Iγ (Gamma index), AUI (Activity utilization index), AUI (Activity utilization index), E (Annual effective dose), AGDE (Annual gonadal dose equivalent), RLI (Representative level index), Din (Indoor air absorbed dose rate), Dout (Outdoor air absorbed dose rate), and ELCR (Excess lifetime cancer risk). The study suggests that HK public fills should be used for the trial reclamation rather than building-house materials. This provides valuable insights for the resource utilization and minimizing environmental pollution of HK public fills. The aim is to offer fundamental technical assistance for future waste resource utilization, ecological protection, and restoration in the Guangdong-Hong Kong-Macao Greater Bay Area.


Assuntos
Baías , Hong Kong , Monitoramento de Radiação/métodos , Materiais de Construção/análise
2.
Hepatology ; 70(5): 1785-1803, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31066068

RESUMO

Cancer cells metabolize different energy sources to generate biomass rapidly. The purine biosynthetic pathway was recently identified as an important source of metabolic intermediates for these processes. However, very little was known about the regulatory mechanisms of purine metabolism in hepatocellular carcinoma (HCC). We explored the role of dual-specificity tyrosine (Y) phosphorylation-regulated kinase 3 (Dyrk3) in HCC metabolism. Dyrk3 was significantly down-regulated in HCC compared with normal controls. Its introduction in HCC cells markedly suppressed tumor growth and metastasis in xenograft tumor models. Mass spectrometric analysis of metabolites suggests that the effect of Dyrk3 on HCC occurred at least partially through down-regulating purine metabolism, as evidenced by the fact that inhibiting purine synthesis reverted the HCC progression mediated by the loss of Dyrk3. We further provide evidence that this action of Dyrk3 knockdown requires nuclear receptor coactivator 3 (NCOA3), which has been shown to be a coactivator of activating transcription factor 4 (ATF4) to target purine pathway genes for transcriptional activation. Mechanistically, Dyrk3 directly phosphorylated NCOA3 at Ser-1330, disrupting its binding to ATF4 and thereby causing the inhibition of ATF4 transcriptional activity. However, the phosphorylation-resistant NCOA3-S1330A mutant has the opposite effect. Interestingly, the promoter activity of Dyrk3 was negatively regulated by ATF4, indicating a double-negative feedback loop. Importantly, levels of Dyrk3 and phospho-NCOA3-S1330 inversely correlate with the expression of ATF4 in human HCC specimens. Conclusion: Our findings not only illustrate a function of Dyrk3 in reprograming HCC metabolism by negatively regulating NCOA3/ATF4 transcription factor complex but also identify NCOA3 as a phosphorylation substrate of Dyrk3, suggesting the Dyrk3/NCOA3/ATF4 axis as a potential candidate for HCC therapy.


Assuntos
Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Proteínas Serina-Treonina Quinases/fisiologia , Proteínas Tirosina Quinases/fisiologia , Purinas/metabolismo , Fator 4 Ativador da Transcrição/metabolismo , Progressão da Doença , Humanos , Coativador 3 de Receptor Nuclear/metabolismo , Fosforilação , Células Tumorais Cultivadas
3.
Environ Geochem Health ; 36(6): 1095-104, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24817613

RESUMO

A study was conducted to investigate the occurrence and behavior of six endocrine-disrupting chemicals (EDCs) in sewage, river water, and seawater from the Pearl River Delta (PRD). The six EDCs under study were 4-nonylphenol (NP), bisphenol A (BPA), 17α-ethynylestradiol (EE2), estrone (E2), 17ß-estradiol (E2), and estriol (E3). These EDCs, predominated by BPA, were found in high levels in the influents and the effluents of sewage treatment plants in the area. The relatively high concentrations (0.23-625 ng/L) of the EDCs detected in the receiving river water suggested that the untreated sewage discharge was a major contributor. The EDCs detected in eight outlets of the Pear River and the Pear River Estuary were in the ranges of 1.2-234 and 0.2-178 ng/L, respectively. The estrogen equivalents in the aquatic environments under study ranged from 0.08 to 4.5 ng/L, with E1 and EE2 being the two predominant contributors. As the fluxes of the EDCs from the PRD region to the nearby ocean are over 500 tons each year, the results of this study point to the potential that Pearl River is a significant source of the EDCs to the local environment there.


Assuntos
Disruptores Endócrinos/análise , Águas Residuárias/análise , Poluentes Químicos da Água/análise , Organismos Aquáticos/efeitos dos fármacos , China , Cromatografia Líquida de Alta Pressão , Disruptores Endócrinos/toxicidade , Monitoramento Ambiental , Estuários , Hong Kong , Medição de Risco , Rios , Água do Mar/análise , Esgotos/análise , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem , Águas Residuárias/toxicidade , Poluentes Químicos da Água/toxicidade
4.
Environ Monit Assess ; 186(1): 87-95, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23982302

RESUMO

Concentrations of Cu, Pb, and As were determined in seawater, surface sediment, Sargassum pallidum collected from the Daya Bay, China. The influence of metal contamination on the marine alga was investigated at chemical and ultrastructural level. Mean concentrations of Cu (19.44 mg kg(-1)) and Pb (33.99 mg kg(-1)) were found to be high in sediment, whereas concentration of As (122.29 mg kg(-1)) in S. pallidum was higher than that in water and sediment. The ultrastructure of S. pallidum cells was anomalous and aberrant. Energy-dispersive x-ray spectroscopic analysis revealed that the nanometal particles in the form of comparatively high-electron density substance diffused in the cell structures constituted by Cu, Pb, As, etc. There is a remarkable similarity or correspondence in the anomalous elements between the geochemistry and the botanic cell, and the heavy metals have potential hazardous effect on the ocean ecology system in Daya Bay.


Assuntos
Baías/química , Metais Pesados/toxicidade , Sargassum/ultraestrutura , Poluentes Químicos da Água/toxicidade , China , Monitoramento Ambiental , Metais Pesados/análise , Sargassum/efeitos dos fármacos , Poluentes Químicos da Água/análise
5.
Front Psychol ; 12: 787833, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34956013

RESUMO

Leaders are under increasing pressure to inspire innovative endeavors in responsible ways. However, whether and how responsible leadership can fuel employee innovative behavior remains unknown. Therefore, drawing on social identity theory and social exchange theory, this study aims to investigate the psychological mechanisms underlying the responsible leadership-innovative behavior relationship. Multi-phase data were collected from 280 employees working in Chinese manufacturing firms to test the hypotheses using hierarchical regression analyses and the bootstrap method. The results reveal that responsible leadership is positively related to innovative behavior. Additionally, perceived socially responsible human resource management (HRM) and organizational pride separately and sequentially mediate the responsible leadership-innovative behavior relationship. This study empirically reveals the effectiveness of responsible leadership and sheds new light on the psychological processes through which it facilitates innovative behavior, revealing the generalizability of responsible leadership and innovative behavior in the Chinese context. Moreover, we respond to the call for incorporating leadership theory into HRM research and further advance the existing knowledge on both antecedents and outcomes of socially responsible HRM. For practical guidance, organizations are encouraged to foster innovation through investment in responsible management practices. Research limitations and implications are also discussed.

6.
Front Cell Infect Microbiol ; 10: 498502, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33324571

RESUMO

The difference between left- and right-sided colon cancer has become the focus of global attention, and researchers have found differences in the morbidity, molecular biological characteristics, and response to targeted drug therapy between left- and right-sided colon cancer. Therefore, the identification of more effective predictive indicators is critical for providing guidance to future clinical work. We collected samples from different colon sites and regions and analyzed the identities and distributions of differentially expressed species in the microbiota in the left and right sides of the colon to better explore the pathogenesis of colon cancer and provided a basis for individualized drug therapy. We collected samples from different regions in the body of 40 patients with colon cancer, including stool and tissues. The Subjects were classified into four groups, and this classification was mainly based on the colon cancer distribution. The microbiota composition of the left-sided and right-sided colon samples was assessed by specifically amplifying the V3-V4 region of the 16S rDNA gene from DNA extracts from the samples. These amplicons were examined by Illumina HiSeq 2500 sequencing. The microbial taxa in the left-sided colon samples are more abundant than those in the right-sided colon samples. The flora in the left-sided colon samples, such as Clostridium perfringens and Fusobacterium nucleatum, might be associated with VEGF expression and are more likely to promote colon cancer. The microbiota distribution in the right-sided colon samples is less invasive and harmful and particularly rich in Bifidobacterium dentium. In addition, Streptococcus, which is the target of EGFR, was found to be expressed in both the left- and right-sided colon samples but was found at a higher level in the left-sided colon samples. Additionally, the differential pathways involved in the left-sided colon samples mainly mediate DNA damage, methylation, and histone modifications, whereas those in the right-sided colon samples are dominated by DNA synthesis. The comparison of only the geographical differences revealed a significant difference in the distribution of the microbial population. The adherent microbiota composition and structural changes between the left- and right-sided colon samples might contribute to the development of colon cancer, lead to different morbidities, and further affect the prognosis of patients and their sensitivity to targeted drugs. Therefore, the identification of the differential flora in the colon could be used as an indicator for predicting the occurrence and development of colon cancer, which is also beneficial for future individualized drug therapy.


Assuntos
Neoplasias do Colo , Microbiota , Bifidobacterium , Colo , Neoplasias do Colo/microbiologia , Feminino , Lateralidade Funcional , Humanos , Masculino
7.
Oncogene ; 39(15): 3145-3162, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32060423

RESUMO

Dysregulation of PARP10 has been implicated in various tumor types and plays a vital role in delaying hepatocellular carcinoma (HCC) progression. However, the mechanisms controlling the expression and activity of PARP10 in HCC remain mostly unknown. The crosstalk between PLK1, PARP10, and NF-κB pathway in HCC was determined by performing different in vitro and in vivo assays, including mass spectrometry, kinase, MARylation, chromatin immunoprecipitation, and luciferase reporter measurements. Functional examination was performed by using small chemical drug, cell culture, and mice HCC models. Correlation between PLK1, NF-κB, and PARP10 expression was determined by analyzing clinical samples of HCC patients with using immunohistochemistry. PLK1, an important regulator for cell mitosis, directly interacts with and phosphorylates PARP10 at T601. PARP10 phosphorylation at T601 significantly decreases its binding to NEMO and disrupts its inhibition to NEMO ubiquitination, thereby enhancing the transcription activity of NF-κB toward multiple target genes and promoting HCC development. In turn, NF-κB transcriptionally inhibits the PARP10 promoter activity and leads to its downregulation in HCC. Interestingly, PLK1 is mono-ADP-ribosylated by PARP10 and the MARylation of PLK1 significantly inhibits its kinase activity and oncogenic function in HCC. Clinically, the expression levels of PLK1 and phosphor-p65 show an inverse correlation with PARP10 expression in human HCC tissues. These findings are the first to uncover a PLK1/PARP10/NF-κB signaling circuit that underlies tumorigenesis and validate PLK1 inhibitors, alone or with NF-κB antagonists, as potential effective therapeutics for PARP10-expressing HCC.


Assuntos
Carcinoma Hepatocelular/patologia , Proteínas de Ciclo Celular/metabolismo , Neoplasias Hepáticas/patologia , Poli(ADP-Ribose) Polimerases/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Fator de Transcrição RelA/metabolismo , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Carcinogênese/efeitos dos fármacos , Carcinogênese/patologia , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/terapia , Proteínas de Ciclo Celular/antagonistas & inibidores , Progressão da Doença , Retroalimentação Fisiológica , Feminino , Células HEK293 , Hepatectomia , Humanos , Estimativa de Kaplan-Meier , Fígado/patologia , Fígado/cirurgia , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/terapia , Masculino , Camundongos , Pessoa de Meia-Idade , Mutagênese Sítio-Dirigida , Estadiamento de Neoplasias , Nitrilas/farmacologia , Nitrilas/uso terapêutico , Fosforilação/efeitos dos fármacos , Poli(ADP-Ribose) Polimerases/genética , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteínas Proto-Oncogênicas/genética , Pteridinas/farmacologia , Pteridinas/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Estaurosporina/farmacologia , Estaurosporina/uso terapêutico , Sulfonas/farmacologia , Sulfonas/uso terapêutico , Fator de Transcrição RelA/antagonistas & inibidores , Ensaios Antitumorais Modelo de Xenoenxerto , Quinase 1 Polo-Like
8.
Oncotarget ; 7(16): 22092-102, 2016 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-26989077

RESUMO

MicroRNAs are critical in various human cancers, including gastric cancer (GC). However, the mechanism underlying the GC development remains elusive. In this study, we demonstrate that miR-448 is increased in GC samples and cell lines. Overexpression of miR-448 facilitated the proliferation of GC cells by stimulating glycolysis. Mechanistically, we identified KDM2B, a reader for methylated CpGs, as the target of miR-448 that represses glycolysis and promotes oxidative phosphorylation. Overexpression of miR-448 reduced both the mRNA and protein levels of KDM2B, whereas KDM2B re-expression abrogated the miR-448-mediated glycolytic activities. Furthermore, we discovered Myc as a key target of KDM2B that controls metabolic switch in GC. Importantly, a cohort of 81 GC tissues revealed that miR-448 level closely associated with a battery of glycolytic genes, in which KDM2B showed the strongest anti-correlation coefficient. In addition, enhanced miR-448 level was significantly associated with poor clinical outcomes of GC patients. Hence, we identified a previously unappreciated mechanism by which miR-448 orchestrate epigenetic, transcriptional and metabolic networks to promote GC progression, suggesting the possibility of therapeutic intervention against cancer metabolic pathways.


Assuntos
Proteínas F-Box/biossíntese , Regulação Neoplásica da Expressão Gênica/genética , Histona Desmetilases com o Domínio Jumonji/biossíntese , MicroRNAs/metabolismo , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Animais , Regulação para Baixo , Glicólise , Xenoenxertos , Humanos , Estimativa de Kaplan-Meier , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias Gástricas/metabolismo
9.
Mar Pollut Bull ; 76(1-2): 394-9, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-23948092

RESUMO

Spatial and temporal variations of mercury (Hg) were investigated from ten representative bays along the coast of Southern China. The total Hg (THg) in surface sediments varied widely with concentrations from 25 to 264 ng/g. As a whole, Hg pollution in several bays occupied by busy sea traffic and industrial activities, such as Shantou (ST) Bay and Dapeng (DP) Bay were remarkably more serious than others, which reflected the direct effects of anthropogenic activities around the coastal areas. Hg variations in sediment cores clearly display upcore rising trend which obviously correlates with the trend of economic development and urbanization in the last five decades. No significant correlations were found between Hg and organic matter and particle size, suggesting that the distribution of Hg is not fully controlled by these variables.


Assuntos
Baías/química , Monitoramento Ambiental , Sedimentos Geológicos/química , Mercúrio/análise , Poluentes Químicos da Água/análise , China , Poluição Química da Água/estatística & dados numéricos
10.
Environ Sci Pollut Res Int ; 19(4): 1305-14, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22086612

RESUMO

PURPOSE: This study assessed the concentrations of platinum (Pt) and palladium (Pd) in surface sediments and sedimentary cores collected from the Pearl River Estuary with a view of evaluating the distribution, background levels, possible sources, and contamination level of anthropogenic Pt and Pd. MATERIALS AND METHODS: Thirty-six samples of surface sediments and 12 samples from sedimentary cores were collected. Al(2)O(3) was analyzed on fused glass disks by X-ray fluorescence spectrometer. Heavy metal elements were measured by inductively coupled plasma-mass spectrometry. Pt and Pd were separated from the sample matrix by anion exchange chromatography and subsequent solvent extraction after samples had been digested in Carius tubes using aqua regia. The analysis of Pt and Pd was performed by isotopic dilution-inductively coupled plasma-mass spectrometry. RESULTS AND DISCUSSION: Pt and Pd concentrations in surface sediments were 0.28-2.11 and 0.39-38.30 ng/g, respectively, and Pt and Pd concentrations in sedimentary cores were 0.19-1.18 and 0.15-1.76 ng/g, respectively. Background values of Pt and Pd were 0.20-1.17 and 0.10-1.34 ng/g, respectively. The spatial distribution of the enrichment factor differed between Pt and Pd in surface sediments. Down-core variations in Pt, Pd, and other heavy metal elements were similar in all cases and were related to sediment type. CONCLUSIONS: Some of the Pt and Pt in surface samples were derived from anthropogenic emissions. Pt and Pd were delivered to the sediment by fluvial input. In addition to vehicle exhaust catalysts, Pt and Pd were derived from other sources (e.g., industrial process). An important post-burial remobilization process of Pt and Pd is likely to be particle mixing by billows caused by typhoon.


Assuntos
Poluentes Ambientais/análise , Sedimentos Geológicos/análise , Paládio/análise , Platina/análise , China , Monitoramento Ambiental , Rios/química , Espectrofotometria Atômica
11.
Talanta ; 81(3): 954-8, 2010 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-20298878

RESUMO

A simple and rapid analytical method for determining the concentration of rhenium in molybdenite for Re-Os dating was developed. The method used isotope dilution-inductively coupled plasma-mass spectrometry (ID-ICP-MS) after the removal of major matrix elements (e.g., Mo, Fe, and W) from Re by solvent extraction with N-benzoyl-N-phenylhydroxylamine (BPHA) in chloroform solution. The effect on extraction efficiency of parameters such as pH (HCl concentration), BPHA concentration, and extraction time were also assessed. Under the optimal experimental conditions, the validity of the separation method was accessed by measuring (187)Re/(185)Re values for a molybdenite reference material (JDC). The obtained values were in good agreement with previously measured values of the Re standard. The proposed method was applied to replicate Re-Os dating of JDC and seven samples of molybdenite from the Yuanzhuding large Cu-Mo porphyry deposit. The results demonstrate good precision and accuracy for the proposed method. The advantages of the method (i.e., simplicity, efficiency, short analysis time, and low cost) make it suitable for routine analysis.


Assuntos
Técnicas de Química Analítica , Hidroxilaminas/química , Espectrometria de Massas/métodos , Molibdênio/química , Rênio/análise , Química/métodos , Ácido Clorídrico/química , Concentração de Íons de Hidrogênio , Íons , Isótopos , Modelos Químicos , Reprodutibilidade dos Testes , Solventes/química , Temperatura , Fatores de Tempo
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