Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 11 de 11
Filtrar
Más filtros












Base de datos
Intervalo de año de publicación
1.
J Environ Sci (China) ; 126: 470-482, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36503773

RESUMEN

Fe-N co-doped coral-like hollow carbon shell (Fe-N-CS) was synthesized via a simply impregnation-pyrolysis method. The Fe-N-CS showed an excellent ability for activating peroxymonosulfate (PMS), which could degrade about 93.74% tetracycline (20 mg/L) in 12 min. The Fe-N-CS/PMS system exhibited a good anti-interference capacity of various pH, inorganic anions, HA and different water qualities. More importantly, the Fe nanoparticles were anchored uniformly in the carbon layer, effectively limiting the metal leaching. The quenching tests and electron spin resonance (ESR) manifested that non-radical singlet oxygen (1O2) was the main reactive oxygen species (ROS) for TC degradation. The mechanism study showed that Fe nanoparticles, defect and graphite N played a key role in activating PMS to produce ROS. Moreover, three probable degradation pathways were proposed by using LC-MS measurements. Generally, this work had a new insight for the synthesis of heterogeneous Fe-N-C catalysts in the advanced oxidation process based on PMS.


Asunto(s)
Antozoos , Compuestos Heterocíclicos , Animales , Oxígeno Singlete , Especies Reactivas de Oxígeno , Carbono , Tetraciclina , Antibacterianos
2.
J Environ Sci (China) ; 111: 351-366, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34949364

RESUMEN

Recently, metal-based carbon materials have been verified to be an effective persulfate activator, but secondary pollution caused by metal leaching is inevitable. Hence, a green metal-free 3D macroscopic N-doped porous carbon nanosheets (NPCN) was synthesized successfully. The obtained NPCN showed high adsorption capacity of tetracycline (TC) and excellent persulfate (PS) activation ability, especially when calcined at 700 °C (NPCN-700). The maximum adsorption capacity of NPCN-700 was 121.51 mg/g by H-bonds interactions. Moreover, the adsorption process followed pseudo-second-order kinetics model and Langmuir adsorption isotherm. The large specific surface area (365.27 mg/g) and hierarchical porous structure of NPCN-700 reduced the mass transfer resistance and increased the adsorption capacity. About 96.39% of TC was removed after adding PS. The effective adsorption of the catalyst greatly shortened the time for the target organic molecules to migrate to the catalyst. Moreover, the NPCN-700 demonstrated high reusability with the TC removal rate of 80.23% after 4 cycles. Quenching experiment and electron paramagnetic resonance (EPR) test confirmed the non-radical mechanism dominated by 1O2. More importantly, the C = O groups, defects and Graphitic N acted as active sites to generate 1O2. Correspondingly, electrochemical measurement revealed the direct electron transfer pathway of TC degradation. Finally, multiple degradation intermediates were recognized by the LC-MS measurement and three possible degradation pathways were proposed. Overall, the prepared NPCN had excellent application prospects for removal of antibiotics due to its remarkable adsorption and catalytic degradation capabilities.


Asunto(s)
Carbono , Tetraciclina , Adsorción , Antibacterianos , Catálisis , Porosidad
3.
J Hazard Mater ; 424(Pt C): 127569, 2022 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-34741936

RESUMEN

Heteroatoms doped carbon materials are widely used in the advanced oxidation process (AOPs) to remove organic pollutants in water due to the synergies effect between different heteroatoms. In this study, a novel kind of N, S co-doped magnetic mesoporous carbon nanosheets (Fe@NS-C) was prepared by simple one-step pyrolysis. Further, the influence of doping amount of S (L-methionine) and N (melamine) on catalytic activity was studied, the optimized sample Fe@NS-C-2-12/PMS showed a satisfying degradation ( 91.07%) for high concentrations of tetracycline (80 mg/L TC) in 10 min, which was attributed to the proper ratio of S content to N content (S(at.%)/ N(at.%)= 0.2097) in the sample could better play its synergistic effect by XPS analysis. The Fe@NS-C-2-12/ PMS system also exhibited satisfactory degradation effects in a wide pH range (3-10) and the existence of inorganic ions and humic acid. Then, the degradation mechanisms were mainly through the non-radical pathway (1O2 and electron transfer) and the major active sites were pyridinic N compared to thiophene S, CO, and Fe-Nx. This study could inspire the design of high-performance active and low-cost heteroatomic doping nano-magnetic catalysts for PMS-based waste treatment.


Asunto(s)
Carbono , Peróxidos , Fenómenos Magnéticos , Tetraciclina
4.
Oncol Rep ; 43(6): 1875-1884, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32323823

RESUMEN

The aim of the present study was to investigate the underlying mechanisms of thymus­expressed chemokine (TECK) autocrine signaling, and its effect on carcinogenesis and the development of breast cancer. The present study also assessed epithelial­mensenchymal transition (EMT) and cell migration, invasion, proliferation and apoptosis. Breast cancer cell lines MCF­7 and MDA­MB­231 were used in the present study, and TECK basic expression in cancer cells was investigated using western blotting (WB). EMT markers, Akt pathway molecules and apoptosis indicators were detected by reverse transcription­quantitative PCR or WB. In order to assess migration and invasion, wound healing and Matrigel invasion assays were performed. Moreover, flow cytometry was used to assess the rate of proliferation and apoptosis. In vivo experiments were conducted in nude mice to assess cancer growth. It was revealed that breast cancer cells could secrete TECK in an autocrine manner. Furthermore, TECK could increase cell migration and invasion by promoting EMT and inhibit apoptosis via the Akt signaling pathway.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/metabolismo , Quimiocinas CC/metabolismo , Animales , Apoptosis/fisiología , Biomarcadores de Tumor/genética , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Línea Celular Tumoral , Movimiento Celular/fisiología , Proliferación Celular/fisiología , Quimiocinas CC/genética , Transición Epitelial-Mesenquimal , Femenino , Regulación Neoplásica de la Expresión Génica , Xenoinjertos , Humanos , Células MCF-7 , Ratones , Ratones Desnudos , Metástasis de la Neoplasia , Transducción de Señal
5.
Environ Pollut ; 259: 113863, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31918139

RESUMEN

Large ammonia (NH3) emissions contribute approximately 8-30% to the fine particle pollution in China and highlight the need for understanding the emission trends and mitigation effects of NH3 in the future. The purpose of this study is to predict the NH3 emissions and analyze the mitigation potential up to year 2040 by scenario analysis based on the established new NH3 emission inventory from anthropogenic sources for the Beijing-Tianjin-Hebei (BTH) region. The results showed that the total NH3 emission in the BTH region was estimated at 966.14 Gg in 2016. Under the Business-as-Usual (BAU) scenario, the total NH3 emissions in 2030 and 2040 would increase by 13% and 26% compared with 2016 levels, with average annual growth rates of 0.9% and 1.0%, respectively. Livestock will continue to dominate NH3 emissions in the future, with the proportions of total emissions increasing from 57% in 2016 to 64% in 2030 and 68% in 2040. The share of the second-largest NH3 emission source, synthetic fertilizer application, will decrease from 36% in 2016 to 31% in 2030 and 27% in 2040. Among five other sources, the largest change occurred in waste disposal, increasing notably by 3.31 times from 2016 to 2040 owing to rapid urbanization. Under the Combined Options (CO) scenario, the total NH3 emissions could be reduced by as much as 34% by 2030 and 50% by 2040 compared with the BAU scenario, which is attributed to livestock (24% in 2030, 37% in 2040) and synthetic fertilizer application (10% in 2030, 13% in 2040), respectively. This study can give a reliable estimation of anthropogenic NH3 emission in the BTH region during 2020-2040 and provide a valuable reference for effective mitigation measures and control strategies for policy makers.


Asunto(s)
Contaminantes Atmosféricos , Amoníaco , Monitoreo del Ambiente , Contaminantes Atmosféricos/análisis , Amoníaco/análisis , Animales , China , Conservación de los Recursos Naturales , Ganado
6.
Environ Pollut ; 260: 113973, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-31991351

RESUMEN

Both agricultural and construction machinery are important non-road sources of atmospheric pollution, with total hydrocarbons (THC), nitrogen oxides (NOx) and particulate matter (PM) emissions accounting for more than 60% of the total emissions from all non-road mobile sources in China. However, there exist relatively few efforts to establish the emission inventory for these machineries. This study attempted to estimate and predict air pollutant emissions from agricultural and construction diesel machinery, using the Beijing-Tianjin-Hebei (BTH) region as the case study area. The results show that total emissions of PM10, PM2.5, THC, NOX, CO and SO2 in 2015 were 41.10, 38.80, 86.14, 520.41, 379.01 and 17.32 Kt respectively. The contribution of agricultural machinery was slightly higher than that of construction machinery, accounting for 60-71% of the total. Moreover, emissions of various pollutants (except SO2) from agricultural machinery were mainly distributed in central Hebei (Cangzhou, Shijiazhuang and Baoding), while emissions from construction machinery were mainly distributed in Beijing and Tianjin. The prediction suggest that the total emissions of agricultural and construction diesel machinery in the BTH region would increase by 6% in 2020 and 9% in 2025. Moreover, pollutant emissions from construction machinery would contribute from 29% to 40% in 2015 to 34%-61% in 2025. These results could provide important information for making effective mitigation measures of non-road mobile sources.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire/estadística & datos numéricos , Monitoreo del Ambiente , Agricultura , Beijing , China , Material Particulado , Emisiones de Vehículos/análisis
7.
J Environ Sci (China) ; 88: 90-102, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31862083

RESUMEN

Sulfide-modified nanoscale zero-valent iron (S-nZVI) is a promising material for removal of organic pollutants from water, but S-nZVI nanoparticles (NPs) easily agglomerate and have poor contact with organic contaminants. Herein, we propose a new S-nZVI/graphene aerogel (S-nZVI/GA) composite which exhibits superior removal capability for trichloroethylene (TCE) from water. Three-dimensional porous graphene aerogel (GA) can improve the efficiency of electron transport, enhance the adsorption of organic pollutants and restrain the agglomeration of the core-shell S-nZVI NPs. The TCE removal rates of FeS, nZVI, GA and S-nZVI were 27.8%, 42%, 63% and 75% in 2 hr, respectively. Furthermore, TCE was completely removed within 50 min by S-nZVI/GA. The TCE removal rate increased with increasing pH and temperature, and TCE removal followed the pseudo-first-order kinetic model. The results demonstrate the great potential of S-nZVI/GA composite as a low-cost, easily separated and superior monolithic adsorbent for removal of organic pollutants.


Asunto(s)
Grafito , Agua Subterránea , Tricloroetileno , Contaminantes Químicos del Agua , Purificación del Agua/métodos , Adsorción , Hierro , Sulfuros , Agua
8.
J Breath Res ; 13(4): 046012, 2019 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-31489846

RESUMEN

Breath analysis is used to detect the composition of exhaled gas. As a quick and non-invasive detection method, breath analysis provides deep insights into the progression of various kinds of diseases, especially those with metabolism disorders. Abundant information on volatile compounds in diabetic patients has been studied in numerous articles in the literature. However, exhaled gas in diabetic patients can be altered by various complications. So far, little attention has been paid to this alteration. In our paper, we found that under air pollution conditions, diabetic patients exhale more nitric oxide. Diabetic patients with heart failure exhale more acetone than those without heart failure. After 13C-labeled glucose intake, patients infected with Helicobacter pylori exhaled more 13C and less 18O than those without infection. Exhalation with chronic kidney disease changes volatile organic compounds on a large scale. Diabetic patients with ketoacidosis exhale more acetone than those without ketoacidosis. Some specific volatile organic compounds also emanate from diabetic feet. By monitoring breath frequency, diabetic patients with obstructive sleep apnea syndrome exhibit a unique breath pattern and rhythm as compared with other diabetic patients, and sleep apnea is prevalent among diabetic patients. In addition to clinical findings, we analyzed the underlying mechanisms at the levels of molecules, cells and whole bodies, and provided suggestions for further studies.


Asunto(s)
Pruebas Respiratorias/métodos , Diabetes Mellitus/diagnóstico , Contaminación del Aire/análisis , Espiración , Humanos , Óxido Nítrico , Compuestos Orgánicos Volátiles/análisis
9.
Lipids Health Dis ; 18(1): 103, 2019 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-31010439

RESUMEN

BACKGROUND: Patients with diabetes mellitus were often accompanied with hyperlipidemia. ATP-binding cassette sub-family A member1 (ABCA1) promotes the efflux of lipids and thereby mediates the metabolism of cholesterol. The aim of our study was to determine the associations of ABCA1 gene polymorphisms with the risks of diabetes mellitus and dyslipidemia in diabetic patients. METHODS: We retrieved literature about the relationship between ABCA1 gene polymorphisms (C69T and R230C) and the risk of diabetes through PubMed, Web of Science, EMBASE, Wanfang Database, China National Knowledge Infrastructure (CNKI) and Cochrane database. Weighted mean difference (WMD) and odds ratio (OR) were used to compare continuous and dichotomous variables, respectively, accompanied by their 95% confidence interval (CI). RESULTS: A total of 1746 diabetic patients and 1292 non-diabetic controls were enrolled. All subjects were Caucasians. ABCA1 R230C T allele was significantly associated with reduced the risk of diabetes (OR = 0.75, 95% CI = 0.57-0.98, P = 0.04). There was no association of ABCA1 C69T gene polymorphisms with the risk of diabetes. However, subgroup analyses showed that the ABCA1 C69T gene mutation significantly reduced the risk of hypertriglyceridemia in diabetic patients as compared with that in non-diabetic subjects (dominant model: WMD =0.66, 95% CI = 0.52-0.8, P < 0.0001; recessive model: WMD = 0.47, 95%CI = 0.11-0.83, P = 0.01). CONCLUSIONS: ABCA1 R230C T allele gene mutation is a protective in decreasing the risk of diabetes in Caucasians and ABCA1 C69T gene mutation markedly influences the level of lipid metabolism in diabetic patients.


Asunto(s)
Transportador 1 de Casete de Unión a ATP/genética , Diabetes Mellitus/genética , Diabetes Mellitus/metabolismo , Metabolismo de los Lípidos/genética , Mutación/genética , Genes Dominantes , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Humanos , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple/genética , Sesgo de Publicación , Factores de Riesgo
10.
Medicine (Baltimore) ; 98(2): e13906, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30633164

RESUMEN

BACKGROUND: Qishenyiqi dripping pill for chronic heart failure (CHF) remains controversial due to lack of high-quality trials. Therefore, we conduct this pooled-analysis to evaluate the efficacy and safety of Qishenyiqi in CHF patients. METHODS: We searched for randomized clinical trials for Qishenyiqi dripping pill in treating CHF up to August 2018 through China National Knowledge Infrastructure (CNKI), the PubMed Database, the Wanfang Database, the China Scientific Journal Database (VIP), and the Chinese Biomedicine Literature Service System. RevMan 5.3 was used for pooled analyses. Based on the New York Heart Association (NYHA) classification, the clinical therapeutic effect was collected as the primary endpoint. RESULTS: The efficacy and safety of Qishenyiqi combined with routine treatment significantly increased NYHA functional classification, left ventricular ejection fraction, cardiac index, and 6-minute walking test and decreased brain natriuretic peptide, left ventricular end-diastolic, and end-systolic dimensions with no obvious side effects in comparison with routine therapy alone. CONCLUSIONS: Together these results provide important insights into Qishenyiqi is effective and safe in improving ventricular remodeling and function of CHF patients. PROSPERO REGISTRATION NUMBER: PROSPERO106695.


Asunto(s)
Fármacos Cardiovasculares/uso terapéutico , Medicamentos Herbarios Chinos/uso terapéutico , Insuficiencia Cardíaca/tratamiento farmacológico , Función Ventricular Izquierda/efectos de los fármacos , Remodelación Ventricular/efectos de los fármacos , Fármacos Cardiovasculares/efectos adversos , Enfermedad Crónica , Medicamentos Herbarios Chinos/efectos adversos , Insuficiencia Cardíaca/fisiopatología , Humanos , Péptido Natriurético Encefálico/metabolismo , Ensayos Clínicos Controlados Aleatorios como Asunto
11.
Mol Med Rep ; 15(6): 4100-4108, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28487957

RESUMEN

C-C chemokine receptor type 7 (CCR7) has been implicated in lymph node metastasis of various cancers. Previous studies have revealed that epithelial­mesenchymal transition (EMT) is involved in the chemotactic process mediated by CCR7 and its ligands in various types of carcinoma. However, the underlying mechanism of this process remains to be fully elucidated. The present study investigated whether chemokine (C­C motif) ligand 21 (CCL21)/CCR7 may activate EMT of lung cancer cells and their associated signaling pathways. A549 and H520 lung cancer cell lines were examined in vitro in the present study. The results indicated that A549 and H520 expressed CCR7, but reduced levels of CCL21. Following stimulation of lung cancer cell lines with CCL21, the expression of the epithelial marker E­cadherin was downregulated, and the mesenchymal markers Vimentin/Slug and extracellular signal­regulated kinase (ERK) were upregulated. In addition, the ERK inhibitor PD98059 may inhibit EMT caused by CCL21, and decreased cell migration and invasion initiated by CCL21. Furthermore, lung adenocarcinoma tissues from 50 patients who underwent lung cancer operations were investigated by immunohistochemistry. The findings revealed that CCR7, Slug and Vimentin were highly expressed in lung carcinoma tissues, and were significantly associated with lymph node metastasis and clinical pathological stages, respectively. CCR7 expression was correlated positively with expression levels of Slug and Vimentin. CCL21 was expressed positively in the endothelium of lymphatic vessels adjacent to cancer cells, and weakly in lung cancer cells. Collectively, these results demonstrated that CCL21/CCR7 may activate EMT in lung cancer cells via the ERK1/2 signaling pathway. The current study provides evidence that a close interaction exists between CCL21/CCR7chemotaxis and EMT procedures in lung cancer metastasis, providing a basis for the development of therapeutic targets.


Asunto(s)
Quimiocina CCL21/metabolismo , Transición Epitelial-Mesenquimal , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Receptores CCR7/metabolismo , Transducción de Señal , Adulto , Anciano , Biomarcadores , Línea Celular Tumoral , Movimiento Celular , Quimiocina CCL21/genética , Femenino , Expresión Génica , Humanos , Neoplasias Pulmonares/genética , Metástasis Linfática , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Fenotipo , Fosforilación , Receptores CCR7/genética , Factores de Transcripción de la Familia Snail/genética , Factores de Transcripción de la Familia Snail/metabolismo , Vimentina/genética , Vimentina/metabolismo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...