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1.
Sci Total Environ ; 919: 170559, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38336071

RESUMO

Volatile organic compounds (VOCs) play a major role in O3 formation in urban environments. However, the complexity in the emissions of VOCs and nitrogen oxides (NOx) in industrial cities has made it challenging to identify the key factors influencing O3 formation. This study used observation-based-model (OBM) to analyze O3 sensitivities to VOCs and NOx during summer in a typical industrial city in China. The OBM model results were coupled with a receptor model to analyze the sources of O3. Higher concentrations of O3 precursors were observed during polluted periods indicating that precursor accumulation contributed to the higher maxima of the net ozone formation rate and HOx concentrations. Analyses of ROx· budgets and relative incremental reactivity (RIR) indicated that O3 production is in a chemical transition regime and was sensitive to both VOCs and NOx. Results from Positive Matrix Factorization (PMF) analysis indicated that gasoline vehicle emissions, industrial processes, and coal combustion were major sources of O3 precursors. The sensitivities of O3 production to these sources depend on if both VOC and NOx sensitivities are considered. If only VOCs sensitivity is considered, in contrast, the contribution of anthropogenic sources to O3 production was significantly underestimated. This study highlights the importance of accounting for both VOCs and NOx sensitivities when O3 chemistry is in a transition regime in O3 production attribution studies.

2.
Adv Mater ; : e2311548, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38333964

RESUMO

The diagnosis and treatment of solid tumors have undergone significant advancements marked by a trend toward increased specificity and integration of imaging and therapeutic functions. The multifaceted nature of inorganic oxide nanomaterials (IONs), which boast optical, magnetic, ultrasonic, and biochemical modulatory properties, makes them ideal building blocks for developing multifunctional nanoplatforms. A promising class of materials that have emerged in this context are peptide-functionalized inorganic oxide nanomaterials (PFIONs), which have demonstrated excellent performance in multifunctional imaging and therapy, making them potential candidates for advancing solid tumor diagnosis and treatment. Owing to the functionalities of peptides in tumor targeting, penetration, responsiveness, and therapy, well-designed PFIONs can specifically accumulate and release therapeutic or imaging agents at the solid tumor sites, enabling precise imaging and effective treatment. This review provides an overview of the recent advances in the use of PFIONs for the imaging and treatment of solid tumors, highlighting the superiority of imaging and therapeutic integration as well as synergistic treatment. Moreover, the review discusses the challenges and prospects of PFIONs in depth, aiming to promote the intersection of the interdisciplinary to facilitate their clinical translation and the development of personalized diagnostic and therapeutic systems by optimizing the material systems.

3.
Huan Jing Ke Xue ; 44(7): 3660-3668, 2023 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-37438265

RESUMO

Driven by precursor emissions, meteorological conditions, and other factors, atmospheric ozone (O3) has become the main pollutant affecting urban air quality in summer. The current deductive models driven by physical and chemical mechanisms require a large number of parameters for the analysis of O3 pollution, and the calculation timeliness is poor. The data-driven inductive models are efficient but have problems such as poor explanation. In this study, an explainable model of data-driven Correlation-ML-SHAP was established to reveal the strongly correlated influencing factors of O3 concentration. Additionally, the machine learning ML module coupled with the explainable SHAP module was used to calculate the contributions of driving factors to O3 concentration, so as to realize the quantitative analysis of driving factors. The O3 pollution process in the summer of 2021 in Jincheng City was used as an example to carry out the application research. The results showed that the Correlation-ML-SHAP model could reveal and use strong driving factors to simulate O3 concentration and quantify influence contribution, and the ML module used the XGBoost model to achieve the best simulation accuracy. Air temperature, solar radiation, relative humidity, and precursor emission level were the strong driving factors of O3 pollution in Jincheng City in summer 2021, and the contribution weights were 32.1%, 21.3%, 16.5%, and 15.6%. The contribution weights of air temperature, solar radiation, and precursor emission level increased by 3.4%, 1.2%, and 1.2% on polluted days, respectively, and the contribution weights of precursor emission level rose to third place on polluted days. Each driving factor had a nonlinear interaction effect on O3 concentration. When the air temperature exceeded 24℃, or the relative humidity was lower than 70%, there was a 94.9% and 94.1% probability of positive contribution to O3 pollution, respectively. Under such meteorological conditions, ρ(NO2) exceeded 9 µg·m-3, or ρ(CO) exceeded 0.7 mg·m-3, and there was a 94.9% and 99.3% probability of positive contribution to O3 pollution, respectively. The southeast wind speed was lower than 5.8 m·s-1, or the south wind speed was lower than 5.3 m·s-1, both of which contributed positively to O3 pollution. The model quantitatively analyzed the influence contribution of various driving factors on urban O3 concentration, which could provide a basis for the prevention and control of urban atmospheric O3 pollution in summer.

4.
Environ Pollut ; 323: 121355, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36842622

RESUMO

Hourly observations in northern China city of Taiyuan were performed to compare secondary inorganic aerosol (SIA) reaction mechanisms, and emission effects on SIA during the pre-lock and COVID-19 lock days. Emission control implemented and meteorological conditions during lock days both caused beneficial impact on air quality. NO2 showed the highest decrease ratio of -49.5%, while the relative fraction of NO3- in PM2.5 increased the most (2.7%). Source apportionment revealed the top three contributors to PM2.5 were secondary formation (SF), coal combustion (CC), and vehicle exhaust (VE) during both pre-lock and lock days. EC lock/pre were all lower than 1, suggesting the overall reduction of primary emissions during lock days, while the higher ratio of (SIA/EC) lock/pre (1.01-1.36) indicated the enhanced secondary formation in lock days. The ratio of SIA of pollution to clean days during lock periods considerably higher by 23.7% compared with that in pre-lock periods, which was indicated SIA secondary formation was more pronounced and contributed great to pollution days in lock periods though secondary formation existed in pre-lock and lock periods. Enhanced secondary formation of NO3- and SO42- during lock days might be mainly due to the increased in aqueous and gas-phase reactions, respectively. Except for SF, high contribution of VE and CC were also important for high SIA concentration in pre-lock and lock days, respectively. The decreased contribution of VE weakens its contribution to SIA formation, indicating the effectiveness of VE emission control, as confirmed during the COVID-19 pandemic. This study highlights the aqueous and gas-phase reactions for nitrate and sulfate, respectively, which contributed to heavy pollution, as well as indicated the important role of VE on SIA formation, suggesting the urgent need to further strengthen controls on vehicle emissions.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , COVID-19 , Humanos , Poluentes Atmosféricos/análise , Material Particulado/análise , Pandemias , Estudos Prospectivos , Estações do Ano , Monitoramento Ambiental , Controle de Doenças Transmissíveis , Aerossóis e Gotículas Respiratórios , Poluição do Ar/análise , China , Emissões de Veículos/análise , Água , Carvão Mineral
5.
Sci Total Environ ; 836: 155465, 2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-35500706

RESUMO

Despite the adoption of air quality control measures, the influence of regional transport on volatile organic compounds (VOCs) pollution has gradually increased in Beijing. In this study, the whole observation period (September 24 to December 12, 2020) was divided into heating period and non-heating period to explore the impact of changing VOCs sources in different observation periods, and also classified into "Type-N" and "Type-S" periods both in non-heating period and heating period to explore the impact of regional transport from the northern and southern regions of sampling site, respectively. The average VOCs concentrations in northern Beijing during observation period were 22.6 ± 12.6 ppbv, which showed a decrease trend in recent years compared with other studies. And higher VOCs concentrations were observed in Type-S than in Type-N period. The positive matrix factorization results showed that vehicular exhaust dominated VOCs (26.1%-33.7%), but coal combustion could not be ignored in heating period, when it was twice that in non-heating period. In particular, coal combustion dominated VOCs in southern trajectories (30.9%) in heating period. The analysis of concentration weighted trajectory showed that coal combustion was affected by regional transport from the southeast regions of Beijing, while vehicular exhaust was affected by urban and the southeast regions of Beijing. Regarding human health risks, the carcinogenic risks of benzene and ethylbenzene exceeded the acceptable cancer risk value (1 × 10-6), and were higher in Type-S than in Type-N period. The results indicated that regional transport from urban areas and the areas south of Beijing had a significant impact on VOCs in northern Beijing. Thus, targeted control measures for different potential pollution regions are important for controlling VOCs pollution in Beijing.


Assuntos
Poluentes Atmosféricos , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/análise , Pequim , China , Carvão Mineral/análise , Monitoramento Ambiental , Calefação , Humanos , Emissões de Veículos/análise , Compostos Orgânicos Voláteis/análise
6.
Huan Jing Ke Xue ; 43(3): 1226-1234, 2022 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-35258186

RESUMO

Based on the daily average concentration of PM2.5, social influencing factor data, and meteorological data of 11 cities in Shanxi Province from 2015 to 2019, the concentration period of PM2.5 was determined using wavelet transform. The correlation between PM2.5 and social influencing factors and meteorological factors was explored respectively through Spearman correlation and the wavelet coherence spectrum, and the main influencing factors of long-term and short-term management and control of PM2.5 were determined. The results showed that the concentration of PM2.5 in Shanxi Province showed an upward trend from 2015 to 2017, with an average annual increase rate of 4.3% and a downward trend from 2018 to 2019, with an average annual decrease rate of 4.2%. The average concentration of PM2.5 showed a "U" distribution, with the highest value in January (95 µg·m-3) and the lowest in August (34 µg·m-3); the average value in winter was approximately twice that in summer. The ρ(PM2.5) in southern cities such as Linfen was 62 µg·m-3, and the average value in Datong and other northern cities was 45 µg·m-3, which was high in the south and low in the north. There were significant periodic changes in PM2.5 concentration in the 11 cities, including a long period of approximately 293 d and a short period of approximately 27 d. Among them, the energy consumption level and industrial structure were the strong driving factors affecting the PM2.5 concentration in the long period of Shanxi Province. In the short period, it was greatly affected by the change in atmospheric circulation, and different cities were affected by typical meteorological factors. Linfen, Yuncheng, Datong, Shuozhou, and Xinzhou were vulnerable to wind speed; Jinzhong and Luliang were vulnerable to temperature; and Taiyuan, Jincheng, Yangquan, and Changzhi were uniquely and significantly affected by relative humidity. Therefore, industrial structure adjustment and energy structure adjustment are key to the long-term control of atmospheric PM2.5 and the long-term improvement of air quality in Shanxi Province. The differential impact of different urban meteorological factors on PM2.5 should be considered when carrying out short-term regional joint prevention and control.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluição do Ar/análise , China/epidemiologia , Cidades , Monitoramento Ambiental , Material Particulado/análise , Estações do Ano , Análise de Ondaletas
7.
Environ Pollut ; 291: 118151, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34517178

RESUMO

Ammonia is essential for the generation of secondary inorganic aerosols (SIA) in particulate matter, which affects severely the air quality in north China. In this study, PM2.5 sampling was conducted as well as gaseous pollutant concentration and meteorological parameters were measured from November 2017 to January 2018. PM2.5 concentration was highest in the industrial site (94.8 ± 41.7 µg m-3), followed by urban (40.9 ± 24.1 µg m-3) and rural (35.6 ± 20.3 µg m-3) sites. The mass ratio of NO3-/SO42- exhibited clear site variations, with the highest average value of 1.2 was found at the urban site, likely due to the dense traffic volume resulting in higher emissions of NO2, and the lowest value of 0.9 at the industry site. The presence of Excess-NHx (E-NHx), raising the pH 24 by 1.4, 1.3, and 1.4 units in industry, urban, and rural sites, respectively, might be vital for raising the aerosol pH. Correlation coefficients of Nitrogen oxidation rate (NOR, NOR = [NO3-]/[NO3-] + [NO2]) vs. Photochemical oxidants (Ox, NO2 +O3 in our study) and NOR vs. aerosol water content (AWC) at three sites were implied that both homogeneous and heterogeneous reactions occurred for nitrate formation in industry site, while heterogeneous reactions were dominant in urban and rural sites. Oxidation rates were most sensitive to the variation of E-NHx concentration at rural site, followed by the urban and industry sites, which was shown by the fact that the increase in E-NHx concentration by 1.0 µg m-3 increased the SIA concentration by 1.21, 1.02, and 0.37 µg m-3 at rural, urban, and industry sites, respectively. With the increase in NHx emissions at present, the role of NHx in SIA formation at ammonia-rich atmosphere requires more attention, especially in the less-noticed rural areas.


Assuntos
Poluentes Atmosféricos , Amônia , Aerossóis/análise , Poluentes Atmosféricos/análise , Amônia/análise , China , Monitoramento Ambiental
8.
Public Health Nutr ; 21(4): 756-765, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29151369

RESUMO

OBJECTIVE: Several epidemiological studies have been performed to evaluate the association of fruit and vegetable consumption with risk of the metabolic syndrome (MetS), but the results remain controversial. Thus, we conducted a systematic meta-analysis to assess the associations of fruit or/and vegetable consumption with risk of MetS, separately. DESIGN: We searched PubMed, EMBASE and Web of Science databases up to July 2017 for relevant available articles. Pooled OR with 95 % CI were calculated with the fixed- or random-effects model. RESULTS: A total of nine studies for fruit consumption, nine studies for vegetable consumption and seven studies for fruit and vegetable consumption were identified as eligible for the present meta-analysis. The pooled OR (95 % CI) of MetS for the highest v. lowest category were 0·87 (0·82, 0·92; I 2=46·7 %) for fruit consumption, 0·85 (0·80, 0·91; I 2=0·0 %) for vegetable consumption and 0·76 (0·62, 0·93; I 2=83·5 %) for fruit and vegetable consumption. In subgroup analyses stratified by continent where the study was conducted, the inverse association of fruit consumption (0·86 (0·77, 0·96)) and vegetable consumption (0·86 (0·80, 0·92)) with risk of MetS remained significant in Asia. There was no evidence of small-study effect. CONCLUSIONS: Our meta-analysis indicates that fruit or/and vegetable consumption may be inversely associated with risk of MetS. It suggests that people should consume more fruits and vegetables to decrease the risk of MetS.


Assuntos
Dieta , Comportamento Alimentar , Frutas , Síndrome Metabólica/prevenção & controle , Verduras , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
9.
Eur J Gastroenterol Hepatol ; 29(4): e19-e28, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27926662

RESUMO

Epidemiology studies have been carried out to investigate the association between alcohol consumption and the risk of gallstone disease, but the results remain controversial. We carried out a meta-analysis to quantitatively summarize the evidences from observational studies on alcohol consumption and the risk of gallstone disease. Eligible studies published in English were identified by searching PubMed, Web of Science, and Embase databases. The random-effect model was used to calculate the pooled relative risks (RRs) with 95% confidence intervals (CIs). Restricted cubic splines were used to assess the dose-response relationship. Eight cohort studies and 10 case-control studies were included in our meta-analysis. The pooled RR of gallstone disease for the highest versus the lowest alcohol consumption was 0.62 (95% CI: 0.49-0.78). Statistically significant associations were also found in stratified analysis by study design (cohort studies: RR=0.66, 95% CI: 0.48-0.91 and case-control studies: RR=0.58, 95% CI: 0.45-0.73). With respect to sex, both men (RR=0.57, 95% CI: 0.4-0.8) and women (RR=0.64, 95% CI: 0.53-0.77) showed statistically significant associations between alcohol consumption and the risk of gallstone disease. A linear dose-response relationship was found between alcohol consumption and gallstone disease risk and the risk of gallstone disease decreased by 12% (RR=0.88, 95% CI: 0.84-0.92; Pnonlinearity=0.079) for each 10 g/day increment in alcohol consumption. This meta-analysis suggests that alcohol consumption is associated with significantly decreased risk of gallstone disease.


Assuntos
Consumo de Bebidas Alcoólicas , Cálculos Biliares/prevenção & controle , Consumo de Bebidas Alcoólicas/epidemiologia , Relação Dose-Resposta a Droga , Etanol/administração & dosagem , Medicina Baseada em Evidências/métodos , Cálculos Biliares/epidemiologia , Humanos , Estudos Observacionais como Assunto , Medição de Risco/métodos
10.
J Biol Chem ; 289(33): 22589-22599, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-24982424

RESUMO

CREPT (cell cycle-related and expression elevated protein in tumor)/RPRD1B (regulation of nuclear pre-mRNA domain-containing protein 1B), highly expressed during tumorigenesis, was shown to enhance transcription of CCND1 and to promote cell proliferation by interacting with RNA polymerase II. However, which signaling pathway is involved in CREPT-mediated activation of gene transcription remains unclear. In this study, we reveal that CREPT participates in transcription of the Wnt/ß-catenin signaling activated genes through the ß-catenin and the TCF4 complex. Our results demonstrate that CREPT interacts with both ß-catenin and TCF4, and enhances the association of ß-catenin with TCF4, in response to Wnt stimulation. Furthermore, CREPT was shown to occupy at TCF4 binding sites (TBS) of the promoters of Wnt-targeted genes under Wnt stimulation. Interestingly, depletion of CREPT resulted in decreased occupancy of ß-catenin on TBS, and over-expression of CREPT enhances the activity of the ß-catenin·TCF4 complex to initiate transcription of Wnt target genes, which results in up-regulated cell proliferation and invasion. Our study suggests that CREPT acts as an activator to promote transcriptional activity of the ß-catenin·TCF4 complex in response to Wnt signaling.


Assuntos
Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proteínas de Neoplasias/metabolismo , Fatores de Transcrição/metabolismo , Via de Sinalização Wnt/fisiologia , beta Catenina/metabolismo , Animais , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Proteínas de Ciclo Celular/genética , Proliferação de Células/fisiologia , Células HEK293 , Células HeLa , Humanos , Camundongos , Complexos Multiproteicos/genética , Complexos Multiproteicos/metabolismo , Células NIH 3T3 , Proteínas de Neoplasias/genética , Fator de Transcrição 4 , Fatores de Transcrição/genética , Transcrição Gênica/fisiologia , Regulação para Cima/fisiologia , beta Catenina/genética
11.
Biochem Biophys Res Commun ; 446(1): 387-92, 2014 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-24613385

RESUMO

Transforming growth factor-ß (TGF-ß) signaling plays an important role in regulation of a wide variety of cellular processes. Canonical TGF-ß signaling is mediated by Smads which were further regulated by several factors. We previously reported that E3 ubiquitin ligase CHIP (carboxyl terminus of Hsc70-interacting protein, also named Stub1) controlled the sensitivity of TGF-ß signaling by modulating the basal level of Smad3 through ubiquitin-mediated degradation. Here, we present evidence that Hsp70 and Hsp90 regulate the complex formation of Smad3/CHIP. Furthermore, we observed that over-expressed Hsp70 or inhibition of Hsp90 by geldanamycin (GA) leads to facilitated CHIP-induced ubiquitination and degradation of Smad3, which finally enhances TGF-ß signaling. In contrast, over-expressed Hsp90 antagonizes CHIP mediated Smad3 ubiquitination and degradation and desensitizes cells in response to TGF-ß signaling. Taken together, our data reveal an opposite role of Hsp70 and Hsp90 in regulating TGF-ß signaling by implicating CHIP-mediated Smad3 ubiquitination and degradation. This study provides a new insight into understanding the regulation of the TGF-ß signaling by chaperones.


Assuntos
Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Animais , Células COS , Linhagem Celular , Chlorocebus aethiops , Células HEK293 , Proteínas de Choque Térmico HSP70/química , Proteínas de Choque Térmico HSP90/química , Humanos , Vison , Complexos Multiproteicos/química , Complexos Multiproteicos/metabolismo , Proteólise , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Transdução de Sinais , Proteína Smad3/química , Proteína Smad3/metabolismo , Ubiquitina-Proteína Ligases/química , Ubiquitinação
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