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1.
J Environ Sci (China) ; 108: 44-57, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34465436

RESUMO

Zhengzhou is one of the most haze-polluted cities in Central China with high organic carbon emission, which accounts for 15%-20% of particulate matter (PM2.5) in winter and causes significantly adverse health effects. Volatile organic compounds (VOCs) are the precursors of secondary PM2.5 and O3 formation. An investigation of characteristics, sources and health risks assessment of VOCs was carried out at the urban area of Zhengzhou from 1st to 31st December, 2019. The mean concentrations of total detected VOCs were 48.8 ± 23.0 ppbv. Alkanes (22.0 ± 10.4 ppbv), halocarbons (8.1 ± 3.9 ppbv) and aromatics (6.5 ± 3.9 ppbv) were the predominant VOC species, followed by alkenes (5.1 ± 3.3 ppbv), oxygenated VOCs (3.6 ± 1.8 ppbv), alkyne (3.5 ± 1.9, ppbv) and sulfide (0.5 ± 0.9 ppbv). The Positive Matrix Factorization model was used to identify and apportion VOCs sources. Five major sources of VOCs were identified as vehicular exhaust, industrial processes, combustion, fuel evaporation, and solvent use. The carcinogenic and non-carcinogenic risk values of species were calculated. The carcinogenic and non-carcinogenic risks of almost all air toxics increased during haze days. The total non-carcinogenic risks exceeded the acceptable ranges. Most VOC species posed no non-carcinogenic risk during three haze events. The carcinogenic risks of chloroform, 1,2-dichloroethane, 1,2-dibromoethane, benzyl chloride, hexachloro-1,3-butadiene, benzene and naphthalene were above the acceptable level (1.0  ×  10-6) but below the tolerable risk level (1.0  ×  10-4). Industrial emission was the major contributor to non-carcinogenic, and solvent use was the major contributor to carcinogenic risks.


Assuntos
Poluentes Atmosféricos , Ozônio , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/análise , China , Monitoramento Ambiental , Ozônio/análise , Estações do Ano , Compostos Orgânicos Voláteis/análise
2.
Environ Pollut ; 288: 117982, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34426229

RESUMO

Ammonia (NH3) volatilization is one of the main pathways of nitrogen loss from cropland, resulting not only in economic losses, but also environmental and human health impacts. The magnitude and timing of NH3 emissions from cropland fertilizer application highly depends on agricultural practices, climate and soil factors, which previous studies have typically only considered at coarse spatio-temporal resolution. In this paper, we describe a first highly detailed empirical regression model for ammonia (ERMA) emissions based on 1443 field observations across China. This model is applied at county level by integrating data with unprecedented high spatio-temporal resolution of agricultural practices and climate and soil factors. Results showed that total NH3 emissions from cropland fertilizer application amount to 4.3 Tg NH3 yr-1 in 2017 with an overall NH3 emission factor of 12%. Agricultural production for vegetables, maize and rice are the three largest emitters. Compared to previous studies, more emission hotspots were found in South China and temporally, emission peaks are estimated to occur three months earlier in the year, while the total amount of emissions is estimated to be close to that calculated by previous studies. A second emission peak is identified in October, most likely related to the fertilization of the second crop in autumn. Incorporating these new findings on NH3 emission patterns will enable a better parametrization of models and hence improve the modelling of air quality and subsequent impacts on ecosystems through reactive N deposition.


Assuntos
Amônia , Ecossistema , Agricultura , Amônia/análise , China , Produtos Agrícolas , Fertilização , Fertilizantes/análise , Humanos , Nitrogênio/análise , Solo
3.
Huan Jing Ke Xue ; 42(8): 3663-3675, 2021 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-34309253

RESUMO

Based on the collected urban motor vehicle activity ownership and traffic flow of highways, combined with the mileage and source profiles of VOCs, using the emission factor method, we established high-resolution emission inventories from 2016 to 2019 for urban and 2016-based highway motor vehicles, respectively, in Henan Province, China. The results showed that gasoline vehicles, particularly minibuses and ordinary motorcycles, were the main contributors of CO, VOCs, and NH3, whereas heavy-duty and light-duty diesel trucks emitted SO2, NOx, and PM. Vehicles with China 1, China 3, and China 4 emission standards contributed significantly to pollutant emissions in the fleet. The temporal variation in traffic flow was consistent with the changes in freight and passenger traffic, with higher coefficients of variation for highways from August to October and the lowest in November. The weekly and daily changes in urban trunk roads showed distinct weekend effects and clear double-peak features, respectively. High-value emission areas were concentrated in urban centers with dense transport networks and high traffic volumes and on roads radiating outward from urban areas. The Lianhuo Expressway and the Beijing-Hong Kong-Macau Expressway were high-emission roads. Light-duty gasoline vehicles made the largest contribution to the ozone formation potential (OFP) of VOCs from motor vehicles. Five species, such as ethylene and propylene, contributed significantly to VOC emissions and OFP. The average annual growth rate of vehicle ownership from 2016 to 2019 was 5.7%. Compared with 2016, VOC emissions increased by 2.8% in 2019, whereas emissions of other pollutants showed decreasing trends of different degrees, with decreases of 76.3%, 51.7%, 50.3%, 43.1%, 16.7%, and 5.9% for SO2, PM2.5, PM10, NH3, CO, and NOx, respectively. The emission reduction percentage of each pollutant in 2019 under the control policies relative to the baseline scenario ranged from 15.6% to 82.4%.


Assuntos
Poluentes Atmosféricos , Emissões de Veículos , Poluentes Atmosféricos/análise , Pequim , China , Monitoramento Ambiental , Hong Kong , Macau , Veículos Automotores , Emissões de Veículos/análise
4.
Nat Commun ; 12(1): 3444, 2021 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-34103528

RESUMO

AKT is involved in a number of key cellular processes including cell proliferation, apoptosis and metabolism. Hyperactivation of AKT is associated with many pathological conditions, particularly cancers. Emerging evidence indicates that arginine methylation is involved in modulating AKT signaling pathway. However, whether and how arginine methylation directly regulates AKT kinase activity remain unknown. Here we report that protein arginine methyltransferase 5 (PRMT5), but not other PRMTs, promotes AKT activation by catalyzing symmetric dimethylation of AKT1 at arginine 391 (R391). Mechanistically, AKT1-R391 methylation cooperates with phosphatidylinositol 3,4,5 trisphosphate (PIP3) to relieve the pleckstrin homology (PH)-in conformation, leading to AKT1 membrane translocation and subsequent activation by phosphoinositide-dependent kinase-1 (PDK1) and the mechanistic target of rapamycin complex 2 (mTORC2). As a result, deficiency in AKT1-R391 methylation significantly suppresses AKT1 kinase activity and tumorigenesis. Lastly, we show that PRMT5 inhibitor synergizes with AKT inhibitor or chemotherapeutic drugs to enhance cell death. Altogether, our study suggests that R391 methylation is an important step for AKT activation and its oncogenic function.


Assuntos
Arginina/metabolismo , Carcinogênese/metabolismo , Carcinogênese/patologia , Proteína-Arginina N-Metiltransferases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Antineoplásicos/farmacologia , Biocatálise/efeitos dos fármacos , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Feminino , Células HEK293 , Humanos , Metilação/efeitos dos fármacos , Camundongos Nus , Mutação/genética , Ligação Proteica/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Proteína-Arginina N-Metiltransferases/deficiência , Proteínas Proto-Oncogênicas c-akt/química , Piruvato Desidrogenase Quinase de Transferência de Acetil/metabolismo , RNA Interferente Pequeno/metabolismo , Transdução de Sinais/efeitos dos fármacos
5.
Int J Mol Sci ; 22(4)2021 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-33670113

RESUMO

The mechanistic target of rapamycin (mTOR) is a master regulator of cell growth, proliferation, and metabolism by integrating various environmental inputs including growth factors, nutrients, and energy, among others. mTOR signaling has been demonstrated to control almost all fundamental cellular processes, such as nucleotide, protein and lipid synthesis, autophagy, and apoptosis. Over the past fifteen years, mapping the network of the mTOR pathway has dramatically advanced our understanding of its upstream and downstream signaling. Dysregulation of the mTOR pathway is frequently associated with a variety of human diseases, such as cancers, metabolic diseases, and cardiovascular and neurodegenerative disorders. Besides genetic alterations, aberrancies in post-translational modifications (PTMs) of the mTOR components are the major causes of the aberrant mTOR signaling in a number of pathologies. In this review, we summarize current understanding of PTMs-mediated regulation of mTOR signaling, and also update the progress on targeting the mTOR pathway and PTM-related enzymes for treatment of human diseases.


Assuntos
Doenças Cardiovasculares/metabolismo , Doenças Metabólicas/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias/metabolismo , Doenças Neurodegenerativas/metabolismo , Processamento de Proteína Pós-Traducional , Serina-Treonina Quinases TOR/metabolismo , Doenças Cardiovasculares/genética , Proliferação de Células , Humanos , Doenças Metabólicas/genética , Proteínas de Neoplasias/genética , Neoplasias/genética , Doenças Neurodegenerativas/genética , Transdução de Sinais , Serina-Treonina Quinases TOR/genética
6.
Huan Jing Ke Xue ; 42(2): 604-615, 2021 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-33742854

RESUMO

Based on online monitoring data of air quality and meteorological parameters, the long-term variations, spatial differences, and meteorological influencing factors of ground-level ozone (O3) pollution in Zhengzhou were studied. In addition, the transport pathways and potential source regions of O3 were investigated. The results show that surface O3 concentrations at the city station in Zhengzhou City increased significantly during the period 2014-2018 (P<0.05) with a growth rate of 15.50 µg·(m3·a)-1, and the timespan of exceeding pollutant standards was extended. The monthly O3 variations showed an "M" pattern with the seasonal maximum in summer. The diurnal O3 variations showed a "single-peak" pattern with a diurnal concentrations peak at 15:00-16:00, while the diurnal peak at the rural station was relatively high (130.94 µg·m-3). At the urban station, the exceedance probability of O3 concentrations was relative high when hourly temperature (T) exceeded 23℃, relative humidity (RH) was less than 65%, wind speed (WS) ranged 2.0-4.0 m·s-1, and wind direction was southeast or northeast. Based on the multivariate linear fitting of impact factors on O3, the main controlling factors at the city and industrial sites were also identified as T and RH compared to T and WS at the traffic and suburb sites. Back trajectory analysis and potential sources of O3 during different seasons were significantly different, with the dominant transport trajectories during spring and summer being short-distance and slow-moving airflows from the south and northeast; autumn and winter were characterized by long-distance and quick-moving airflows from the northwest. The high O3 concentrations observed in summer were mainly affected by local photochemical formation and regional transport from Hebei, Shandong, and Anhui Provinces.

7.
J Environ Sci (China) ; 99: 354-368, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33183714

RESUMO

In this study, we conducted an observation experiment from May 1 to June 30, 2018 in Zhengzhou, a major city in central China, where ground ozone (O3) pollution has become serious in recent years. The concentrations of O3 and its precursors, as well as H2O2 and meteorological data were obtained from the urban site (Yanchang, YC), suburban (Zhengzhou University, ZZU) and background sites (Ganglishuiku, GLSK). Result showed that the rates of O3 concentration exceeded Chinese National Air Quality Standard Grade II (93.3 ppbv) were 59.0%, 52.5%, and 55.7% at the above three sites with good consistency, respectively, indicating that O3 pollution is a regional problem in Zhengzhou. The daily peak O3 appeared at 15:00-16:00, which was opposite to VOCs, NOx, and CO and consistent with H2O2. The exhaustive statistical analysis of meteorological factors and chemical effects on O3 formation at YC was advanced. The high concentration of precursors, high temperature, low relative humidity, and moderately high wind speed together with the wind direction dominated by south and southeast wind contribute to urban O3 episodes in Zhengzhou. O3 formation analysis showed that reactive alkenes such as isoprene and cis-2-butene contributed most to O3 formation. The VOCs/NOx ratio and smog production model were used to determine O3-VOC-NOx sensitivity. The O3 formation in Zhengzhou during early summer was mainly under VOC-limited and transition regions alternately, which implies that the simultaneous emission reduction of alkenes and NOx is effective in reducing O3 pollution in Zhengzhou.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Ozônio , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/análise , China , Cidades , Monitoramento Ambiental , Peróxido de Hidrogênio , Ozônio/análise , Compostos Orgânicos Voláteis/análise
8.
Huan Jing Ke Xue ; 41(10): 4436-4445, 2020 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-33124375

RESUMO

During the National Traditional Games of Ethnic Minorities (NTGEM) 2019, air quality in Zhengzhou was analyzed to evaluate the impact of pollution prevention and control measures on Zhengzhou. Ground-observed meteorological and pollutant data as well as the chemical compositions of volatile organic compounds (VOCs) were investigated. The results showed that the six parameters of pollutants in the safeguard period in 2019 indicated a downward trend as compared with that during the same time in 2018, and the average concentrations of PM2.5 and PM10 were decreased by 16.2% and 25.1%, respectively. However, the average concentration of O3 was only reduced by 3.7%. The daily proportions of primary pollutants of O3 increased to 90% during the NTGEM, and the ozone pollution was severe in this period. Meanwhile, the concentration of total volatile organic compounds (TVOCs) in the safeguard period was 26.21×10-9, which was significantly lower than that during the historical period. Six emission sources of the VOCs were identified using PMF model, including vehicle exhaust (28%), LPG evaporation (21%), combustion source (16%), industrial emissions (15%), solvent utilization (15%), and biogenic VOCs (5%). During the NTGEM period, the control of combustion sources and industrial sources was evident.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Ozônio , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/análise , Monitoramento Ambiental , Ozônio/análise , Emissões de Veículos/análise , Compostos Orgânicos Voláteis/análise
9.
Huan Jing Ke Xue ; 41(8): 3500-3510, 2020 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-33124322

RESUMO

In this study, volatile organic compound (VOC) species were measured at an urban site in Zhengzhou from January 3 to 23, 2019, to investigate the composition, variation characteristics, sources, and effects on secondary organic aerosol (SOA) formation of VOCs at different pollution levels. Results showed that oxygenated VOCs and alkanes were the main components of VOCs, while ethyl acetate and acetone were the most abundant species. During the process from clean days to heavy pollution days, the mixing ratio of VOCs approximately doubled, and the mixing ratios of most species continued to increase as the pollution level increased. Based on the positive matrix factorization (PMF) model, during the observation period, VOCs mainly originated from vehicle emissions, industrial emissions, combustion sources, solvent utilization, and liquefied petroleum gas (LPG) utilization. There were significant differences in the source contribution at different pollution levels, and the contributions of industrial emissions and solvent utilization during the heavy pollution days increased to 9 times and 3 times that of the clean days, respectively. With respect to the SOA formation potential (SOAp), aromatics were the component that contributed the most, and toluene and m/p-xylene were the species that contributed the most, while solvent utilization was the greatest source contributor. During the heavy pollution period, the total SOAp increased to approximately 2.6 times that of clean days. There is a great need to reduce winter haze pollution in Zhengzhou by strengthening the control of aromatic emissions and related sources such as solvent utilization.


Assuntos
Poluentes Atmosféricos , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/análise , Monitoramento Ambiental , Estações do Ano , Emissões de Veículos/análise , Compostos Orgânicos Voláteis/análise
10.
Oncogenesis ; 9(9): 81, 2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32913192

RESUMO

Endometrial cancer stem cells (ECSCs) are stem-like cells endowed with self-renewal and differentiation abilities, and these cells are essential for cancer progression in endometrial cancer (EC). As hallmarks of the tumour microenvironment (TME), hypoxia and hypoxia-inducing factors (HIFs) give rise to the dysregulation of tumour stemness genes, such as SOX2. Against this backdrop, we investigated the regulatory mechanisms regulated by HIFs and SOX2 in ECSCs during EC development. Here, ECSCs isolated from EC cell lines and tissues were found to express stemness genes (CD133 and aldehyde dehydrogenase, ALDH1) following the induction of their ECSC expansion. Notably, m6A methylation of RNA and HIF-1α/2α-dependent AlkB homologue 5 (ALKBH5) participate in the regulation of HIFs and SOX2 in EC, as confirmed by the observations that mRNA levels of m6A demethylases and ALKBH5 significantly increase under hypoxic conditions in ECSCs. Moreover, hypoxia and high ALKBH5 levels restore the stem-like state of differentiated ECSCs and increase the ECSC-like phenotype, whereas the knockdown of HIFs or ALKBH5 significantly reduces their tumour initiation capacity. In addition, our findings validate the role of ALKBH5 in promoting SOX2 transcription via mRNA demethylation, thereby maintaining the stem-like state and tumorigenicity potential of ECSCs. In conclusion, these observations demonstrate a critical role for m6A methylation-mediated regulation of the HIF-ALKBH5-SOX2 axis during ECSC expansion in hypoxic TMEs.

11.
Huan Jing Ke Xue ; 41(2): 587-599, 2020 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-32608717

RESUMO

The spatio-temporal characteristics of ozone (O3) pollution in the Henan Province in 2017 and its relationship with particulate matter, precursors, and meteorological factors were studied using the data obtained from the air quality monitoring station and national baseline ground climate station. Results showed that the annual mean O3 concentration of a maximum daily 8-h average (MDA8) was 108 µg·m-3 in the Henan Province with the trend of summer > spring > autumn > winter. Different levels of O3 were observed in various cities. The number of days exceeding the standard was up to 88 days in Anyang, while the lowest was found in Xinyang with 17 days. The most severe of O3 pollution occurred during late spring and early summer. During this period, the average monthly concentration of O3 MDA8 was above 140 µg·m-3, and peaked in June. The qualitative and quantitative analysis showed that the monthly average concentration of O3 MDA8 was negatively correlated with particulate matter, and the O3 hourly concentration was also negatively correlated with CO and NO2. The O3 MDA8 concentration and meteorological factors (sunshine duration, temperature, rainfall, visibility, humidity, and wind speed) had different correlations during different seasons and various cities.

12.
Huan Jing Ke Xue ; 41(6): 2577-2585, 2020 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-32608771

RESUMO

Ambient volatile organic compounds (VOCs) were determined by GC 5000 online gas chromatography in the urban site of Zhengzhou from April 15 to May 15, 2018. Based on chemical composition analysis, in this study, the concentrations, ozone formation potential (OFP), and source apportionment were studied. The results show that the averaged volume fraction of VOCs in Zhengzhou during spring was 40.26×10-9, which was 23% higher on polluted days (44.12×10-9) than on non-polluted days (35.82×10-9). The contribution of VOC species to OFP was in the order: alkenes > aromatics > alkanes > alkyne. The five factors identified by the PMF model were liquefied petroleum gas (LPG) volatilization sources (66.05%), motor vehicle exhaust sources (47.39%), industrial solvent sources (37.51%), fuel combustion sources (37.80%), and biogenic sources (11.25%). The contributions of LPG volatilization sources and biogenic sources on polluted days were higher by 22.92% and 68.50% than on non-polluted days, respectively.

13.
Chemosphere ; 250: 126283, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32120148

RESUMO

On 3rd to May 24, 2018, volatile organic compound (VOC) samples were collected four times a day by using stainless steel canisters at an urban site in Zhengzhou, China. The concentrations, compositions, sources, ozone (O3) formation potential (OFP), and health risk assessment of VOCs were discussed based on the measurements of 103 VOC species. Results show that the average mixing ratio of VOCs was 29.11 ± 15.33 ppbv, and the dominant components comprised oxygenated VOCs (OVOCs) and alkanes, followed by halocarbons, alkenes, aromatics, and a sulfide. Various groups of VOCs had typical diurnal variation characteristics. Alkenes, alkanes, and aromatics contributed most to the OFP. Five sources identified by the positive matrix factorization model revealed solvent utilization as the largest contributor, followed by industrial production, long-lived and secondary species, vehicular emission, and biogenic emission. Solvent utilization and vehicular emission were important sources to OFP. During O3 episode days, the mixing ratios of alkanes, alkenes, halocarbons, OVOCs, aromatics, and TVOCs decreased to varying degrees; the source contribution of solvent utilization decreased significantly while industrial production showed the opposite trend. VOC species and sources posed no non-carcinogenic risk while five species and all sources except for biogenic emission had carcinogenic risks to exposed population. Industrial emission was the largest contributor to both non-carcinogenic and carcinogenic risks. These results will help to provide some references for O3 pollution research and prevention and control of pollution sources.


Assuntos
Monitoramento Ambiental/métodos , Ozônio/toxicidade , Saúde da População Urbana/normas , Compostos Orgânicos Voláteis/análise , Poluentes Atmosféricos/análise , Alcanos/análise , China , Humanos , Ozônio/análise , Ozônio/química , Medição de Risco
14.
J Environ Sci (China) ; 90: 29-40, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32081325

RESUMO

To investigate the characteristics of ground level ozone (O3) for Henan Province, the ambient air quality monitoring data of 2015 and 2016 were analyzed. The result showed that the 8 h-max-O3 concentrations displayed a distinct seasonality, where the maximum and minimum values, averaging 140.41, 54.19 µg/m3, occurred in summer and winter, respectively. There is a significant correlation between meteorological factors and O3 concentration. The Voronoi neighborhood averaging analysis indicated that O3, temperature, and ultraviolet radiation in Henan province were decreased from northwest to southeast, while relative humidity and precipitation displayed the opposite trend. Besides meteorological factors, the chemical processes play an essential role in ozone formation. Reactions of NO, NO2 and O3 form a closed system, and the partitioning point of the OX-component (O3 + NO2) was at 40 and 80 µg/m3 for nitrogen oxide (NOX) in winter and summer, respectively, with NO2 dominating at higher NOx pollution and O3 being the major component at lower levels. The relationship between oxidant (OX = O3+NO2) and NOx concentrations were evaluated to understand the regional and local contribution of OX. It showed that high regional contribution occurred in the spring, whereas the highest local contribution lead to the summer peak of O3 observed in Zhengzhou. This present study reveals important environment impacts from the photochemical process and the meteorological conditions in the region with better understanding on the O3 characterization.


Assuntos
Poluentes Atmosféricos , Dióxido de Nitrogênio , Ozônio , China , Monitoramento Ambiental , Estações do Ano , Raios Ultravioleta
15.
Nat Cell Biol ; 22(2): 246-256, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32015438

RESUMO

The Hippo and mammalian target of rapamycin complex 1 (mTORC1) pathways are the two predominant growth-control pathways that dictate proper organ development. We therefore explored potential crosstalk between these two functionally relevant pathways to coordinate their growth-control functions. We found that the LATS1 and LATS2 kinases, the core components of the Hippo pathway, phosphorylate S606 of Raptor, an essential component of mTORC1, to attenuate mTORC1 activation by impairing the interaction of Raptor with Rheb. The phosphomimetic Raptor-S606D knock-in mutant led to a reduction in cell size and proliferation. Compared with Raptor+/+ mice, RaptorD/D knock-in mice exhibited smaller livers and hearts, and a significant inhibition of elevation in mTORC1 signalling induced by Nf2 or Lats1 and Lats2 loss. Thus, our study reveals a direct link between the Hippo and mTORC1 pathways to fine-tune organ growth.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Proteínas Serina-Treonina Quinases/genética , Proteína Enriquecida em Homólogo de Ras do Encéfalo/genética , Proteína Regulatória Associada a mTOR/genética , Proteínas Supressoras de Tumor/genética , Animais , Sistemas CRISPR-Cas , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Feminino , Edição de Genes , Células HCT116 , Células HEK293 , Células HeLa , Xenoenxertos , Humanos , Fígado/anormalidades , Fígado/metabolismo , Células MCF-7 , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Camundongos , Camundongos Nus , Camundongos Transgênicos , Miocárdio/metabolismo , Miocárdio/patologia , Neurofibromina 2/deficiência , Neurofibromina 2/genética , Tamanho do Órgão , Proteínas Serina-Treonina Quinases/deficiência , Proteínas Serina-Treonina Quinases/metabolismo , Proteína Enriquecida em Homólogo de Ras do Encéfalo/metabolismo , Proteína Regulatória Associada a mTOR/metabolismo , Transdução de Sinais , Proteínas Supressoras de Tumor/deficiência
16.
Huan Jing Ke Xue ; 41(1): 115-124, 2020 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854911

RESUMO

This study uses the national ambient air quality station data of Anyang City from 2014 to 2017 to analyze the characteristics and variation rules of ozone (O3) in different functional zones (urban, suburban, and industrial), and also studies meteorological influencing factors and potential source distributions of O3 pollution. The results showed that the O3 concentration in Anyang increased significantly between 2014 and 2017, whereby pollution started to advance from 2015 and the earliest occurrence of an O3 pollution episode was in April 2017. The 90th percentile and average concentrations of O3 in the industrial zone increased at faster rates (average annual growth of 16.0 µg·m-3 and 13.0 µg·m-3, respectively) than of those in the urban and suburban zones. The O3 concentrations at the suburban site showed the fastest increase of all zones at the 5th percentile (average annual growth of 13.2 µg·m-3). The monthly variation in O3 concentrations in Anyang showed an "M" pattern that varied spatially depending on the zone. Temperature played a leading role in O3 concentrations; air temperatures >23℃, relative humidity <58%, and a wind speed of 5 m·s-1 in a south-southwesterly direction were closely related to the occurrence of high O3 concentrations. Potential sources of O3 in different seasons were significantly different, and mainly distributed in southern Hebei, northern Hubei, and northern Shenyang in summer. The first heavy O3 pollution day in the studied period was in May 2017, at which time the highest O3 concentration was found in the industrial zone (up to 405 µg·m-3). This heavy O3 pollution episode was related to the continuous high temperature that was caused by the transfer of a dry, hot air mass in western China.

17.
Huan Jing Ke Xue ; 40(10): 4372-4381, 2019 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854804

RESUMO

Ambient volatile organic compounds (VOCs) samples were collected at five sites in Zhengzhou during the spring of 2018. VOCs concentrations, the ozone formation potential (OFP), the aerosol formation potential (AFP), and source apportionment using a positive matrix factorization (PMF) model were studied based on chemical composition analysis. The results showed that the averaged concentration of VOCs in Zhengzhou during spring was (30.66±13.60)×10-9, of which the proportion of alkanes was the highest (35.3%) followed by oxygenated VOCs (OVOCs, 25.3%), halocarbons (24.1%), aromatics (10.0%), and alkenes (5.2%). The total OFP was 195.53 µg·m-3 and the contributions of alkanes, alkenes, aromatics, halocarbons, and OVOCs were 25.6%, 17.8%, 38.9%, 5.8%, and 11.9%, respectively. The total AFP was 0.95 µg·m-3 with an 87.6% contribution from aromatics and 12.4% from alkanes. The correlation between major species showed that pentane, isopentane, benzene, and toluene in Qinlinglu (QLL) site and Jingkaiqu (JKQ) site were greatly influenced by motor vehicles, but these were mainly influenced by combustion sources in Zhengzhou University (ZZU) site. The five factors that were identified by the PMF model were vehicle and liquefied petroleum gas (LPG) volatilization source (30.5%), solvent coating source (27.3%), industrial process source (22.1%), aging air mass (14.4%), and biogenic source (5.7%).

18.
J Environ Sci (China) ; 84: 80-96, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31284919

RESUMO

Central Plains region of China, represented by Henan Province, is facing serious air pollution problems. Vehicular exhaust emissions had adverse impacts on the atmospheric environment. The first comprehensive and novel vehicle emission inventory for Henan Province using vehicle kilometers traveled, localized emission factors, and activity data at city-level was developed. Furthermore, 3 km × 3 km gridded emission and temporal variations were determined by using localized information. Results show that the total emissions of sulfur dioxide (SO2), nitrogen oxides (NOx), carbon monoxide (CO), particular matter with aerodynamic diameter < 10 µm (PM10), aerodynamic diameter < 2.5 µm (PM2.5), volatile organic compounds (VOCs), VOCs-evaporation and ammonia in 2015 were 9.1, 533.4, 1190.7, 23.7, 21.6, 150.8, 31.5 and 10.4 Gg, respectively, and the emission intensities of the above pollutants were 0.05, 2.7, 6.0, 0.1, 0.1, 0.8, 0.2 and 0.05 g/km, respectively. Vehicles meeting the Primary China 1, China 3 and China 4 contributed 89.1%, 82.7%, 75.3%, 75.5%, 75.5%, 68.2%, 68.4% and 82.3% for SO2, NOx, CO, PM10, PM2.5, VOCs, VOCs-evaporation and ammonia emissions, respectively. Zhengzhou, Zhoukou, Nanyang, Luoyang, Shangqiu and Xinyang showed relatively higher emissions and contributed more than 50% of each pollutant. The spatial distribution indicated obvious characteristics of the road network, and high-level emission was concentrated in the downtown areas. Additionally, the ozone formation potential (OFP) based on the estimated speciated VOC emissions was 569.6 Gg in Henan Province. Aliphatic and aromatic hydrocarbons were the main species of VOCs, whereas olefins contributed the largest proportion of OFP, with 42.2%.


Assuntos
Poluentes Atmosféricos , Poluição Relacionada com o Tráfego/estatística & dados numéricos , Emissões de Veículos , China , Cidades/estatística & dados numéricos , Ozônio , Compostos Orgânicos Voláteis
19.
J Mol Med (Berl) ; 97(4): 541-552, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30806715

RESUMO

Renal fibrosis is a common histomorphological feature of renal aging and chronic kidney diseases of all etiologies, and its initiation and progression are substantially influenced by aberrant epigenetic modifications of fibrosis-susceptible genes, yet without effective therapy. "Epigenetic diets" exhibit tissue-protective and epigenetic-modulating properties; however, their anti-renal fibrosis functions and the underlying mechanisms are less understood. In this study, we show that genistein, a phytoestrogenic isoflavone enriched in dietary soy products, exhibits impressive anti-renal fibrosis activities by recovering epigenetic loss of Klotho, a kidney-enriched anti-aging and fibrosis-suppressing protein. Mouse fibrotic kidneys induced by UUO (unilateral ureteral occlusion) displayed severer Klotho suppression and adverse expression of renal fibrosis-associated proteins, but genistein administration markedly recovered the Klotho loss and attenuated renal fibrosis and the protein expression abnormalities. The examination of possible causes of the Klotho recovery revealed that genistein simultaneously inhibited histone 3 deacetylation of Klotho promoter and normalized the promoter DNA hypermethylation by suppressing elevated DNA methyltransferase DNMT1 and DNMT3a. More importantly, genistein's anti-renal fibrosis effects on the renal fibrotic lesions and the abnormal expressions of fibrosis-associated proteins were abrogated when Klotho is knockdown by RNA interferences in UUO mice. Thus, our results identify Klotho restoration via epigenetic histone acetylation and DNA demethylation as a critical mechanism of genistein's anti-fibrosis function and shed new lights on the potentials of epigenetic diets in preventing or treating aging or renal fibrosis-associated kidney diseases. KEY MESSAGES: Genistein prevents renal fibrosis and the associated Klotho suppression in UUO mice. Genistein upregulates Klotho in part by reversing the promoter histone 3 hypoacetylation. Genistein also preserves Klotho via relieving Klotho promoter hypermethylation. Genistein demethylates Klotho promoter by inhibiting aberrant DNMT1/3a expression. Genistein restoration of Klotho is essential for its anti-renal fibrosis function.


Assuntos
Desmetilação do DNA/efeitos dos fármacos , Genisteína/uso terapêutico , Glucuronidase/genética , Substâncias Protetoras/uso terapêutico , Insuficiência Renal Crônica/tratamento farmacológico , Acetilação/efeitos dos fármacos , Animais , Epigênese Genética/efeitos dos fármacos , Fibrose , Histonas/genética , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Regiões Promotoras Genéticas/efeitos dos fármacos , Insuficiência Renal Crônica/genética , Insuficiência Renal Crônica/patologia
20.
Environ Pollut ; 247: 515-523, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30708313

RESUMO

Size-resolved samples were collected using a 14-stage impactor during four seasons in Zhengzhou and analyzed for 26 elements to calculate the health risks from atmospheric particle-bound metals. High concentrations of heavy metals were observed in ultrafine (10.2 (Ni)-66.9 (Cd) ng m-3) or submicrometer (11.4 (Ni)-134 (Pb) ng m-3) mode in winter. Two size-dependent models were used to estimate the deposition of inhaled toxic metals in various regions of the human respiratory system. Results show that heavy metals deposited in the alveolar region ranged from 7.6 (As)-375 (Al) ng m-3 and were almost concentrated in ultrafine and fine modes. Cd (2.2-8.6) may cause accumulative non-carcinogenic health effects on children, and Cr (1.0 × 10-4-2.2 × 10-4) may lead to carcinogenic health risks for nearby residents around the sampling site. The major sources by principal component analysis that contributed to Cr and Cd in ultrafine and fine particles were coal combustion, vehicular and industrial emissions. The atmospheric dry deposition fluxes of Cr and Cd were between 0.7 and 1.9 µg m-2 day-1 calculated by a multi-step method. From the environmental and public health perspective, environmental agencies must control the emission of heavy metals in the atmosphere.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Monitoramento Ambiental , Exposição por Inalação/estatística & dados numéricos , Material Particulado/análise , Atmosfera/análise , Atmosfera/química , Criança , China , Cidades , Carvão Mineral/análise , Poeira/análise , Humanos , Indústrias , Metais Pesados/análise , Estações do Ano
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